ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (20,996)
  • Chemical Engineering  (17,974)
  • Genetics  (2,277)
  • Animals
  • ESR
  • Wiley-Blackwell  (20,275)
  • Elsevier  (721)
Collection
  • Articles  (20,996)
Years
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 2000 (2000), S. 447-454 
    ISSN: 1434-1948
    Keywords: Zinc ; Metalloporphyrins ; Porphyrins ; Cations ; Radicals ; ESR ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Zinc(II) complexes of substituted tetraphenylporphyrins, Zn[T(X-P)P], where X = H, p-F, p-Cl, m-Cl, p-CH3O, and m-CH3O, have been synthesized and characterized. Peripheral substitution shows marked changes in the chemical shifts of the phenyl proton resonances and E1/2 values of the redox couples in the anodic region while the UV/Vis spectra are unaffected. The monocation radicals of these complexes are generated by chemical oxidation with bromine. The ESR spectra reveal the formation of two types of radical species, Zn[T(X-P)P]+·Br- (species I) and Zn[T(X-P)(Brn-P)]+·Br- (species II): Species I at 298 K shows a spectrum, with well-resolved bromine hyperfine features, characteristic of a 2A2u electronic ground state while species II, except for the complex with X = m-CH3O, shows a featureless, isotropic resonance attributable to a 2A1u state. Zn[T(m-CH3O-P)(Brn-P)]+·Br-, on the other hand, exhibits nine resolved nitrogen hyperfine features corresponding to a 2A2u state. Variable temperature ESR spectra (77-298 K) indicate reduction in the bromine and nitrogen hyperfine coupling constants and an increase in the g value of species I from 2.0049 to 2.0060 with lowering temperature and suggest a labile electronic ground state for species I. The p-CH3O substituted complex exhibits an electronic transformation from 2A2u to 2A1u while the remaining complexes, including m-CH3O, show a transformation from 2A2u to an admixed 2A1u/2A2u state. The effect of substitution on the variable temperature ESR spectra are discussed.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0887-624X
    Keywords: polyalkylpropiolate ; Rh complex catalyst ; isomerization ; ESR ; soliton ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alkylpropiolate having n-hexadecyl moiety in the ester group was stereospecifically polymerized with a [Rh(norbornadiene)Cl]2 complex catalyst in alcohol to give rise to cis-transoid polyacetylenes in high yields. The unusually facile cis to trans isomerization for the polymer was found to be induced when the polymer was warmed to even less than ca. 57°C. Under these conditions ESR spectra bearing hyperfine structures due to the radicals generated by the rotational scission in the cis-π bond were observed. This isomerization induced a large g value shift in the ESR spectra together with an increase of the radical concentration during the isomerization, indicating formation of planar conjugated trans sequences that stabilize mobile unpaired electrons as solitons. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2457-2461, 1998
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0887-624X
    Keywords: postpolymerization reactions ; ESR ; polymeric matrices termination reactions ; H-transfer reactions ; kinetic constants ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction kinetics in the dark of photopolymerized mono- and dimethacrylates in a polymeric binder has been studied. Electron spin resonance spectroscopy (ESR) provided useful information regarding the nature of the radicals involved in postpolymerization reactions. Computer simulations were performed to study the decay of the propagating radicals by considering normal bimolecular termination and transfer reactions of the radicals to the binder. Differences were found in the termination reactions for mono- and difunctional monomers when they were photopolymerized in a solid medium. Absolute kinetic constants for H-transfer reaction with the binder, relative kinetic rate constants for radical-radical coupling, and average lifetimes for the radicals have been calculated. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2785-2791, 1998
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0887-624X
    Keywords: photopolymerization kinetics ; ESR ; polymeric binders ; radical environment ; photocalorimetry ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The photopolymerization of several di- and tetrafunctional (meth)acrylic monomers in the presence of a styrene-butadiene-styrene polymeric matrix (SBS) has been studied. Electron spin resonance spectroscopy (ESR) and differential scanning photocalorimetry (photo-DSC) were used as monitoring techniques to identify the photogenerated radicals and analyze photopolymerization profiles, radical environments, and radical secondary reactions. The study of the photopolymerization and/or photocrosslinking reactions of these monomers in the solid media was carried out by taking into consideration different factors, such as the influence of both monomer and photoinitiator structures on the hydrogen abstraction in the binder with formation of benzylic and allylic radicals, the polymerization of the monomers itself and the hydrogen abstraction reaction in the polymerized acrylic chains. Finally, irradiation of the system SBS/photoinitiator in the absence of monomer was also accomplished. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2775-2783, 1998
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1449-1455 
    ISSN: 0887-624X
    Keywords: radical copolymerization ; p-t-butoxystyrene ; dibutyl maleate ; penultimate effect ; ESR ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of p-tert-butoxystyrene (TBOSt) (M1) and di-n-butyl maleate (DBM) (M2) with dimethyl 2,2′-azobisisobutyrate (MAIB) in benzene at 60°C was studied kinetically and by means of ESR spectroscopy. The monomer reactivity ratios were determined to be r1 = 2.3 and r2 = 0 by a curve-fitting method. The copolymerization system was found to involve ESR-observable propagating polymer radicals under practical copolymerization conditions. The apparent rate constants of propagation (kp) and termination (kt) at different feed compositions were determined by ESR. From the relationship of kp and f1 (f1 = [M1]/([M1] + [M2])) based on a penultimate model, the rate constants of five propagations of copolymerization were evaluated as follows; k111 = 140 L/mol s, k211 = 3.5 L/mol s, k112 = 61 L/mol s, k212 = 1.5 L/mol s, and k121 = 69 L/mol s. Thus, a pronounced penultimate effect was predicted in the copolymerization. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1449-1455, 1998
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 61-67 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Risk assessments have been performed to determine the risk associated with the transportation of hazardous wastes through a city. In the course of these assessments, a number of modeling issues arose relating to transportation accident rates, the characterization of incidents, the effect of thermal radiation, the impact of exposure to toxic chemicals, and the threshold for acceptable risk. This paper discusses these issues.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. S3 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 98-103 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This paper presents the design of ribbon wound pressure vessels useful for Ammonia, Urea and Methanol plants. The design is to create a thin shell of 1/5 the total wall thickness required, weld it to the end pieces, and wind 4 to 8 mm thick ribbons of 80 mm width at an angle of 15 to 30 degrees on the inner shell, using a prestress. The ribbons are welded at the ends and an even number of layers are wound cross-helically on to the shell. With more than 7000 vessels over the pressure range of 50 to 350 atmospheres in use in the various chemical industries in China over the past 30 years, their safety record has been excellent. Of particular interest has been the application of this technology in the Ammonia and Urea plants, where the design allows fabrication of these vessels at substantial reduction in cost, and early delivery, when compared to the mono wall technology.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 20-22 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Most audits try to look at a representative selection of the plant procedures and equipment. An alternative is a survey, a look in depth at selected procedures (such as those for testing alarms and trips, issuing permits-to-work, controlling modifications, taking samples or testing relief devices) or selected equipment (such as level glasses or equipment for handling LPG). If the procedure or equipment is well-chosen, surveys may make a bigger contribution to safety, per person-hour, than a conventional audit.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 39-42 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Under OSHA 1910.119, all Process Safety Management (PSM) facilities are required to keep their pressure relief system design information current. This article demonstrates why a pressure relief system design verification effort must be based on an equipment list, rather than a relief device list, in order to ensure that every piece of equipment is adequately protected. The formerly common practice of simply checking the design bases of all existing relief devices is deficient is deficient since this technique does not systematically ensure that every piece of equipment is protected.The “Berwanger Method” is a step by step process for designing or analyzing a pressure relief system to meet OSHA 1910.119 Process Safety Information (PSI) and Process Hazard Analysis (PHA) mandates. The method uses a relational database which tracks the relationships between protected equipment, potential overpressure scenarios, and protective devices.The challenge facing an operating company does not end once the design basis has been “verified” - the design basis information must also be maintained and be readily accessible to avoid costly reinvention of the wheel down the road. The “Berwanger Method” also addresses these maintenance issues.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 49-60 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This paper reports on a comprehensive literature search and small scale experimental work on the reaction characteristics of phosphorous trichloride and water. More than 30 tests were conducted, including both closed and open test cells. The water to phosphorus trichloride molar ratio was varied from 1 to 25. When in contact, water and phosphorus trichloride will form two liquid layers with a reaction starting at the interface. The impact of variables on reaction rates including the interface surface area, layer depth, and stirring were investigated experimentally. A reaction rate model that fits all the measured data is presented. Case studies illustrating the use of this data for emergency relief systems and vent containment design are presented in reference. [1].
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 68-73 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Two major accidents in the 80's: the summit Tunnel Fire, England and Piper Alpha disaster, an offshore platform in the North Sea; and very recently, possible explosion of the Boeing, TWA flight 800 at New York, makes it imperative that further research into the mechonisms of the ignition of flammable vapor/air mixture in contact with hot surfaces needs to be done. There have been a number of studies of ignition by hot surfaces, but in all these studies the ignition sources were wire, sphere or strip, i.e., most of them were flat surfaces. But to the authors' knowledge, other variables which affect the ignition mechanism such as irregular geometrical shapes have not been studied. The purpose of this paper is to examine how the degree of confinement (or, configuration), size and orientation, of the heated surface affects the ignition temperature of the flammable vapors. The results were obtained by experimentnal and by computational fluid dynamics.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 36 (1998), S. 2095-2102 
    ISSN: 0887-6266
    Keywords: molecular motion ; polyisobutylene ; isolated chain ; ESR ; Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly(isobutylene) (PIB) chains with a radical at the chain end were graft-copolymerized on the poly(tetrafluoroethylene) (PTFE) surface in vacuo at 77 K. The PIB chains tethered on the PTFE surface in vacuo were regarded as isolated chains from neighboring tethered PIB chains. The molecular motion of the ends of the isolated PIB chains was observed by an electron spin resonance (ESR) spectrometer in the temperature range from 3 to 125 K, which was lower than Tg of PIB, 200 K,1 and two motion modes were found: One is a quantum tunneling of the methyl group located at the chain end at 3 K, and the other is an interconformation transition with freely rotating methyl group at the end at 77 K, where the transition rate was estimated to be 15 MHz at that temperature. The transition rate increased with an increase in temperature. The activation energy of the transition was estimated to be 370 J/mol. The high mobility and low activation energy was attributed to the isolation of PIB chains in vacuo. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 2095-2102, 1998
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. S3 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 9-15 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The design and deflagration pressure relief vents is based on correlations developed for various types of combustible materials and for enclosures of different strengths. The primary guideline for deflagration vent design in the US is NFPA 68 Guide for Venting of Deflagrations [5]. That document gives guidance for the design of vents for enclosures containing flammable gases, specifically hydrogen, coke oven gas, propane, and methane. Application of the guide to other gases is achieved using the KG value. Values of KG are published for a relatively small number of gases, as seen in Table D-1 of NFPA 68. This work present KG data on several additional gases obtained in a laboratory scale test vessel along with analysis of the results with respect to published values of fundamental burning velocity.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 23-31 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In May 1996, the Flammable and Combustible Liquids Code Committee of the National Fire Protection Association (NFPA) proposed for adoption by the Association a new edition of NFPA 30, Flammable and Combustible Liquids Code. This new edition was the culmination of two and one-half years' work by the Committee and included one of the most significant changes to that document in some twenty years: the incorporation of mandatory fire protection criteria for warehouses and other inside areas that store flammable and combustible liquids in containers and portable tanks.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 32-38 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This paper describes the development of a risk ranked Inspection Recommendation procedure that is used by one of Exxon's chemical plants to prioritize repairs that have been identified during equipment inspection.As part of the Company's Safety Management Practices initiative in the late 1980's a procedure was put into place to ensure that an Inspector's repair recommendations were properly addressed by the organization. The initial procedures were successful at “systematizing” the documentation and stewardship-to-completion of the Inspector's recommendation, however, there were complications with the original process: (1)The Inspector made a simple High, Medium or Low assessment of the priority/criticality of the recommendation. Frequently, this resulted in disagreements with Operations about the true priority of the recommendation.(2)If there was agreement on the priority of the recommendation, there was still disagreement on the relative rank within the priority-which high priority was the highest priority?(3)With limited funds to spend on repairs, it was (and is) important to make sure that the money was being spent on the highest risk items that had the greatest risk reduction/cost benefit ratio.To address these concerns, the procedure was modified to incorporate a risk assessment of the recommendation by both the Inspector and Operations. In the new procedure, the Inspector describes the deficiency that he/she finds and assesses the probability of failure within a certain time-frame. Operations must assess the consequences, from an environmental, safety and economics standpoint, were the failure to occur. These assessments are combined in the typical risk equation (risk = probability × consequences) to arrive at a severity index which serves to rank the recommendation relative to the other recommendations. Because Operations participates in the assessment there is very little disagreement about the priority of the recommendation. The severity index puts the recommendations in order so it is quite clear which are the highest priority recommendations. This process has helped to focus the entire organization on those deficiencies that represent the greatest risk with the result that less time and money is spent correcting items that have a low risk/cost benefit ratio, allowing these savings to be used to reduce the higher risks in the plant.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 124-126 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A simple analytical method is presented for estimating the hybrid minimum ignition energy (HMIE) of dust-gas mixtures, based on the assumed generality of Bartknecht's well-known test data for mixtures of propane with a series of dusts in air. Since the HMIE equation requires input data which might be unavailable, the use of conservative default methods is discussed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 138-148 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A large and potentially hazardous decrease in aldehyde autoignition temperature (AIT) occurs with increased pressure. The AIT-pressure curve determined in a 5 L stainless steel sphere was similar for propionaldehyde and butyraldehyde in air, falling from about 185°C at atmospheric pressure to 90°C at 140 psia. Reduction of oxygen concentration had little effect on propionaldehyde AIT. At 100°C and 140 psia, autoignitions accompanied by at least a doubling of pressure were observed above 4% oxygen. In the presence of a few grams of free liquid, propionaldehyde vapor ignited in air at initial conditions significantly below the AIT. The mechanism appears to involve rapid Fe-catalyzed exothermic liquid-phase oxidation leading to autoignition of the adjacent heated gas layer. An acetaldehyde vapor-air mixture in the presence of free liquid and rust exploded at room temperature when air pressure was increased to 95 psia; this result is discussed with reference to a cylinder overpressurization that occurred while making up an ostensibly sub-LFL calibration mixture with compressed air. Propionaldehyde's limiting oxygen concentration (LOC) was investigated in the near-autoignition region using the same 5L apparatus; the findings are discussed with reference to an overpressurization incident in an air-liquid partial oxidation reactor. The general results are used to illustrate the application of LOC in partial oxidation processes subject to autoignition and to discuss elements of the current ASTM draft test method for LOC, which does not address test difficulties associated with condensable and/or reactive gas systems.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. F3 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 157-170 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Risk analysis in chemical process industries is an elaborate exercise involving several steps from preliminary hazard identification to development of credible accident scenarios, to preparation of strategies for prevention or control of damage.All this requires substantial inputs of time and money. In order to get an approximate yet workable assessment of risk at much lesser costs, indices have been developed which link typical findings of elaborate risk analysis to scales of risk. The scales, in turn, provide workable measures of hazards/risks/safety.In the past, indices have been reported for swift risk assessment - the noteworthy among them include Dow fire and explosion index, Mond fire, explosion and toxicity index, IFAL index, and mortality index. A few rapid ranking techniques have also been proposed.This paper presents a new system of methodologies for Hazard Identification and Ranking (HIRA). The system consists of two indices: one for fire and explosion hazards and another for the hazard due to likely release of toxic chemical. The magnitudes of these indices indicate the severity of the likely accident; in terms of the size of the impacted area.HIRA has been applied to a typical chemical process industry - a sulfolane plant - and its performance has been compared with that of the Dow's and the Mond's indices. The study reveals that HIRA is more sensitive and accurate than the other indices.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 200-208 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 213-218 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: On October 31, 1987 a crane lifting a heat exchanger convection section failed and severed a 4″ loading line and a 2″ pressure relief line to an HF alkylation reactor settler drum at a petroleum refinery in Texas City, Texas. Vapors were emitted under pressure for about two hours and the vessel was plugged and drained aproximately 44 hours later. A plume from this accidental release passed through residential areas, damaging some vegetation (brown lawns), and spawning a class action law suit. An extensive analysis was conducted to determine the total inventory loss and to model the blowdown process and the concentrations of HF in the plume. Since the discharge rate was decreasing with time, a peak concentration of HF in the emitted vapors occurred just before the water spray mitigation system became fully operative. Consequently, the mitigation efforts were more effective late in the response when concentrations were already low. The predicted plume concentrations are consistent with observed vegetation damage effects, with concentrations below Emergency Response Planning Guideline Level 3 past 3/4 mile from the source. These results support a policy of sheltering in place during such an event.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A fifty-five gallon steel drum of a liquid organic peroxide pressurized and ruptured in the mix room of a manufacturing plant. The head of the drum blew off and the ejected material ignited. The resulting fire was extinguished by the building sprinkler system and operating personnel. Although there were no injuries, the fire caused significant damage in the mix room. The investigation of this incident, its likely cause, and the corrective actions will be discussed.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 238-242 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The Brazoria County Petrochemical Council, 13 companies that are working together to enhance relations between industry and the community, united in a joint effort at complying with the EPA's Risk Management Program. One of the significant issues the group had to address was the need to develop meaningful hazard assessment for presentation to the public. The EPA's “Table Look-Up Approach” found in the Offsite Consequence Analysis Guidance document is certainly a good tool; however, the built-in conservatism results in over-estimates of potential hazard areas. Much more meaningful results are shown to be obtained using one of the hazard release models.The value of using a credible scenario with realistic meteorological data is demonstrated through the consistently smaller areas predicted by the PHAST Model for planning purposes. Realistic scenarios/failure modes and realistic model parameters are important so that the risk to the public is not overstated. Proprietary models such as PHAST are invaluable in providing more meaningful consequences for planning purposes.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 263-271 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Some of the hazards encountered by process plant operators involve the operation of in-line valves to control, start, and to stop flow. Torque required to operate valves may vary according to valve wheel size, in-line pressure, and valve flange position (open/closed). This study determined how valve wheel size, in-line pressure and valve position (open/closed) affect torque required to actuate a valve. Data were gathered with each combination of size, pressure and position for 336 valves in an operating petrochemical process facility. The results indicate that the main effects of valve wheel size, the in-line pressure, and open/closed valve position significantly affect operational torque requirements. In addition, the interaction between position and pressure was significant for operational torque. The implication of these results is that operators are exposed to operational torque requirements that exceed maximum acceptable capabilities that have been determined in previous studies.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 288-296 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An ammonia storage tank was built at the BASF Antwerp site in 1969 on land reclaimed from the sea. After several years of operation uneven foundation settlement, of up 2, occurred. In order to assure stability of this area for the next operation period (at least 10 years) measures were taken to ensure continued safe operation. One key measure was strain gauge monitoring at the location of maximum stress.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 297-301 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The Baker-Strehlow methodology was developed to provide an objective approach to prediction of blast pressures from vapor cloud explosions. The complete methodology was first published in 1994 [1]. Since then, it has evolved through ongoing research and use in VCE hazard analyses, facility siting studies and accident investigations. This article gives a brief overview of a paper on recent developments in the Baker-Strehlow methodology presented at the 31st Loss Prevention Symposium in Houston on March 9-13, 1997. Because the entire paper is too lengthy to be presented here, the following discussions may be lacking in some details. A copy of the complete paper can be obtained from the American Institute of Chemical Engineers (AIChE).Since the Baker-Strehlow method was first published, it has been used extensively in VCE hazard assessments in refineries and chemical plants. As expected, many practical lessons have been learned during the course of the hazard assessments, and the Baker-Strehlow method has evolved as a result. The changes have been evolutionary, not revolutionary. In keeping with the goals of the original study in which the methodology was developed, all changes have been incorporated with the intent of achieving an objective methodology to provide consistent prediction of VCE blast effects.The revisions to the Baker-Strehlow method resulting from experience gained during plant walk-downs and hazard assessments include: Systematic identification of “potential explosion sites” or “PESs,”Selection of the level of confinement for mixed zones of 2D and 3D confinement,Deciding on flame expansion when confinement is elevated above the vapor cloud,Selecting the reactivity for a fuel that is a mixture of fuels with differing reactivities,Predicting blast loads when there are multiple PES's within a vapor cloud considering different ignition source locations.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 83-85 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Safety, health and loss prevention are major areas of interst for the American Institute of Chemical Engineers (AIChE). There has been an evolution of these concerns over the years in the Institute just as it has in industry. This article chronicles this evolution.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998) 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 1-8 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Recent guidelines released by the U.S. EPA define a worst-case scenario as a release under stable atmospheric conditions defined as Pasquil-Gifford stability class F. Unfortunately, very few tests at F stability have been available heretofore to provide a basis for models. Recent test data with propane releases by the German research organization TUV provide a set of 60 experiments conducted specifically to define the effects of atmospheric stability class on dispersion. Of these, 25 tests were at F stability. A comparable number were at each other stability class A through E. In addition 23 tests were at wind speeds under 1.5 m/s in stable atmospheres. This paper reports on adjustments made to our models based on these new data by reducing the originally-postulated sensitivity to stability class. In spite of considerable scatter in the TUV data, particularly between two different types of propane analyzers, the model allows us to extract information by averaging over the tests.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 16-19 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A multi-disciplinary team developed a guideline for determining access restriction zones around vented solids handling equipment. The guideline provides a method for ensuring the discharge from a vented explosion will not cause injury to personnel. The steps in this method include: calculating the extent of external hazards from vented explosions; identifying potential areas where personnel could be exposed to a hazard; identifying ways to eliminate or reduce the hazard area; and establishing and documenting any access restrictions needed. Hazard zone calculations use the latest knowledge from research into fireball size, flame length and external pressure equations in VDI 3673. The guideline provides guidance for using this information. Options for mitigating or reducing external hazards from vented explosions are also described. As part of the project, the team audited several solids handling systems to look for potential oversights in existing restricted access areas. Some of the team's learnings from these audits are reviewed.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 43-48 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This paper defines situation awareness (SA) and discusses its importance to operator-machine system safety and functioning in the context of process control activities. Specifically, identified are relationships of human detection of critical process cues converying the status of automated control systems and operator interpretation of the meaning and relevance of such information to the potential for negative incidents in chemical processing. Beyond individual operator SA in interacting with control systems, intra- and inter- work team SA are discussed for supporting individual attainment of process control responsibilities. Factors critical to team SA are discussed. “Road blocks” to team SA are also analytically examined. Lastly, methods for assessing individual and team SA are reviewed and vehicles for relating outcomes of these methods to changes in process control operator and team behavior to improve human-machine system safety and performance are relayed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998) 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 74-81 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The knowledge of the ingition behavior of dust-air mixtures due to electrical sparks (MIE, Minimum Ignition Energy) and hot surfaces (MIT, Minimum Ignition Temperature) is important for risk assessments in chemical production plants. The ignition behavior determines the extent and hence the cost of preventive protection measures.This paper describes the use of the minimum ignition energy and minimum ignition temperature as very important safety indexes in practice.Based on the latest results from large scale experiments on pneumatic filling of silos with polymeric materials and new results of full scale filling tests using Flexible Intermediate Bulk Containers (FIBC) manufactured from a variety of materials, guidance can be given to ensure safe operation in different situations such as filling, emptying operations, type of powder handled.The aim of this paper is to assist people dealing with product. It reflects the present state of the art and current knowledge of the assessment and measures associated with powder handling.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 104-106 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In mid-1997, an Advanced Process Control (APC) scheme was implemented at a resins manufacturing complex with the goal of minimizing flare fuel gas usage while maintaining sufficient energy (BTU/SCF flare gas) to be in environmental regulatory compliance. Prior to APC implementation, the flare system was manually controlled by plant operators with minor attention paid to the minimization of fuel gas usage. Since implementation, APC has saved the plant thousands of dollars in fuel gas costs and reduced unnecessary combusted fuel gas emissions.Hazard analysis techniques were used in the development of the control scheme. An overview of the APC used, the economic evaluation, and the hazard analysis techniques used in the project are presented here.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 107-123 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In the risk assessment parlance, especially with reference to chemical process industries, the term “domino effect” is used to denote “chain of accidents,” or situations when a fire/explosion/missile/toxic load generated by an accident in one unit in an industry causes secondary and higher order accidents in other units. The multi-accident catastrophe which occurred in a refinery at Vishakhapatnam, India, on September 14, 1997, claiming 60 lives and causing damages to property worth over Rs 600 million, is the most recent example of the damage potential of domino effect.But, even as the domino effect has been documented since 1947, very little attention has been paid towards modeling this phenomena. In this paper we have provided a conceptual framework based on sets of appropriate models to forecast domino effects, and assess their likely magnitudes and adverse impacts, while conducting risk assessment in a chemical process industry. The utilizability of the framework has been illustrated with a case study.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998) 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 149-154 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: This article deals with fire protection for water miscible flammable liquids stored in plastic containers packaged in boxes located on pallets. A series of fire tests was conducted with palletized rack storage arrangements using in-rack sprinkler protection at various levels. The intent of the paper is to present data from this test series for these types of commodities. The paper will identify various existing water miscible flammable liquid products stored in this fashion and provide background information for protecting this type of storage as it relates to NFPA 30 Flammable and Combustible Liquids Code. The test data indicates that further research work is needed in the area of plastic containers for use with the storage of combustible and flammable liquids. Included in the paper are discussions concerning possible protection strategies and suggestions for future research which would benefit those involved in risk management of this type of commodity.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 176-183 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The safest method to prevent fires and explosions of flammable mixtures in the first place. This method requires detailed knowledge of the flammability region as a function of the fuel, oxygen, and nitrogen concentrations. A triangular flammability diagram is the most useful tool to display the flammability region, and to determine if a flammable mixture is present during plant operations.This paper describes how to draw and use a flammability diagram. A procedure to estimate the flammability region using the available and sometimes limited data is discussed. The paper also shows how to use the flammability diagram with plant operations involving inerting and purging, and from bringing vessels into and out of service. A compilation of flammability diagrams for 30 materials, based on previously published data is provided.An automated apparatus for acquiring data for a flammability diagram is described. The apparatus consists of a 20-L sphere with an automated gas mixing system, a fuse-wire ignition system, and a high speed pressure measurement and data acquisition system. Data derived from the apparatus includes flammability limits, maximum pressure during combustion, and the maximum pressure rate. The effect of fuse-wire ignitor dynamics on the results is studied. A flammability diagram for methane drawn from data obtained from the apparatus, is presented.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 86-97 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Regulatory issues related to material safety have made the accurate measurement and/or prediction of flash points essential. The flash point is one of the major physical properties used to determine the fire and explosion hazards of a liquid. Flash points are used by virtually all governmental entities worldwide to define “flammable” and “combustible” materials for shipping and safety regulations.A model is described here for the calculation of closed cup flash points for multicomponent, single liquid phase, mixtures. The model is based upon rigorous vapor/liquid equilibrium calculations supplemented with information about the lower flammable limits (LFL's) and heats of combustion (ΔHc's) for the mixture's constituent components. The closed cup flash points predicted with this model are typically within ± 5°C of the experimentally reported values. Such a model is useful as a means of verifying experimental data and as a tool for screening product formulations prior to experimental flash point determination. The model should considerably enhance the safety evaluation portion of the product development cycle, thus leading to shortened product time-to-market cycles. While flash points calculated with this model are in excellent agreement with experiment, experimental determination is still encouraged for critìcal safety applications.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 134-137 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: National Advisory Committee's Acute Exposure Guideline Levels (AEGLs) for ammonia are critically evaluated. The technical bases for concern about AEGL-2 and AEGL-3 values derived by the committee are summarized recommendations made.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 127-133 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An explosion and flash fire in a fixed bed reactor occurred at a municipal wastewater treatment plant (WWTP). Two employees were injured in the accident. The accident occurred in an ozone treatment building where ozone was used to treat odors from the offgas of the sludge concentration units. Excess ozone manually was routed to the fixed bed reactor (ozone destruct unit) where the ozone is catalytically transformed into oxygen before being discharged to the atmosphere.An investigation of the accident was conducted to determine the root cause of the explosion and flash fire and identify corrective actions which the WWTP management could undertake to prevent a recurrence. This investigation included site inspections, interview with the injured employees, sampling and analysis of various materials, an explosion dynamics analysis, and a root cause analysis.It was concluded that cooling oil from one of the ozone generation units entered the main ozone gas line due to a crack in one of the reactor's dielectric tubes. The cooling oil was vented into the ozone destruct unit when an employee opened a ball valve on the main ozone gas line. The cooling oil, essentially a saturated hydrocarbon mixture, reacted exothermically when it contacted the manganese dioxide catalyst. The exothermic reaction resulted in an explosion which propelled the access panel outwards and dispersed the catalyst pellets. A flash fire followed the explosion. The flash fire burned two employees and caused thermal damage to a nearby control panel.Although this accident was the first of its kind at this facility, this was not the first time that the ozone generator had experienced a failure of a dielectric tube. Thus, there was a significant probability that a dielectric tube failure could leak cooling oil into the main ozone gas line. This failure event could, in turn, result in another explosion and flash fire. The WWTP staff neither designed nor fabricated the ozone generator-destructor system. Therefore, it did not seem appropriate for the WWTP staff to modify the ozone system. Instead, it was recommended that the ozone destruct unit be taken out of service. The WWTP management acted on this recommendation.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 171-175 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An explosion occurred in a petroleum product storage tank at a refinery. The liquid petroleum product was a heavy oil used as an asphalt extender. There were no injuries, but the cleanup was costly. The storage tank was one of several which received the product stream from a dehydration unit. The accident occurred shortly after the refinery was brought back on-line following a shutdown for schduled maintenance.This was the first incident of this kind to occur at this facility. Analysis of the process data and eyewitness observations indicated that the dehydration tower, which was supposed to be maintained at a minimum of 100°C during the shutdown, was allowed to drift below 100°C for an unknown period of time. This deviation enabled liquid water to enter the storage tank. Three operational factors contributed to the accident. Corrective actions were recommended to prevent a recurrence of a similar incident.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 184-189 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Dust explosions have been with us for a long time. The first record of a dust explosion occurred in Turin, Italy, on December 14, 1785 [1]. The detailed record of this event is left to us by Count Morozzo. The event took place in Mr. Giacomelli's bakery. We know from his account that the weather was unseasonably dry, that a boy who worked in the bakery was using a shovel to stir and transfer the flour to a chute from a store room to the bakery and he had a lighted lamp to work by. The rest, as the saying goes, is history. No one was killed, and the building was saved by the sagacious fact of having plenty of windows. Since that first record, of course, there have been many explosions with much loss of life and significant economic consequences.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 190-195 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The RSST DIERS vent sizing methodology is revised to provide realistic design equations for reactive systems consistent with available large-scale experience. Using easy to obtain RSST data such as rate of temperature rise and rate of pressure rise excellent agreement is illustrated for hybrid, vapor and gassy reactive systems.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 196-199 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: From the 1960s onwards, the chemical and oil industries developed and used a number of new safety techniques which, in time, became second nature to those who applied them. They included the use of QRA for deciding priorities, Hazop and audits for identifying problems, inherently safer design for avoiding hazards, and more thorough investigation of incidents for identifying underlying causes. However, it has not yet become second nature to remember the accidents of the past and the actions needed to prevent them happening again.I joined industry in 1944 and moved to production in 1952. Then, and for at least 15 years afterwards, safety was a non-technical subject that could be left to arts graduates and elderly foremen. There was concern that people should not be hurt - great attention was paid to the lost-time accident rate - but there was no realization, that it was a subject worthy of systematic study by experienced technologists.This view changed at the end of the 1960s. A new generation of plants had been built, operating at higher temperatures and pressures and containing larger inventories of hazardous chemicals; the result was a series of fires and explosions and a worsening fatal accident rate. Figure 1 shows the situation in ICI, at the time the UK, s largest chemical company. Other companies experienced a similar state of affairs.As a result in 1968, I was appointed one of the company's first technical safety advisers, an unusual appointment at the time for someone with my experience, and if the reason for my appointment had not been so obvious I would have wondered what I had done wrong. I and my colleagues tried to apply the same sort of systematic thinking to safety that we applied in our other professional work. We developed some new concepts and techniques and adopted others. A common feature of our ides, realized only in restrospect, was that they consisted of more than mere problem-solving techniques. Once people had got used to these new concepts and used them a few times, they began to look at a whole range of problems in a different way.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. W3 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 259-262 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Case histories of 65 incidents in runaway reactions and emergency relief in Taiwan were analyzed and classified into several categories according to their causes, materials involved, equipment types, reaction types, and ignition sources. The cases in reactors and storage tanks were examined in more detail owing to the higher probability or larger potential hazard in these two types of equipments. The most common consequence of the incidents are explosions, fires, and atmospheric release of toxic chemicals. The most severe case was a thermal explosion from an organic peroxide storage area which caused the death of 33 persons. Popping and direct releasing of process chemicals to the atmosphere from relieving devices cause the greatest environmental concerns to the community close to the plants. Runaway reactions in batch type reactors occur frequently due to various operational mistakes. Heat of reaction is the most frequent ignition source of runaway reactions and emergency relief.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 272-277 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: EPA's Risk Management Program regulation, promulgated in June 1996 as 40 CFR Part 68 requires subject industries to submit Risk Management Plans by June 1999. This plan requires hazard assessment of the operations of a facility using worst case scenarios and alternative releases. EPA has provided an Off-site Consequence Analysis (OCA) guidance to help facilities in their hazard assessment.OxyChem will be significantly impacted by the RMP rule. This paper outlines OxyChem's general experience and its strategy in planning to comply with this rule. OxyChem's approach in the development of the scenarios required by the rule is described in this paper. Limitations involved in the use of EPA's look-up tables or a single modeling solution for conducting all of the OCA are discussed. A three tiered OCA approach is presented as a possible alternative.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 209-212 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: HFC-227ea (CF3CHFCF3;1, 1, 1, 2, 3, 3, 3-heptafluoropropane) is an effective replacement for Halon 1301 in fire suppression systems, providing rapid extinguishment of flames through a combination of physical and chemical mechanisms. The vast majority of applications for HFC-227ea involve the protection of Class A hazards, which are characterized by low fuel loadings and low energy output, with fire sizes often in the range of 5-10 kW. Mid- and large-scale testing has demonstrated that HFC-227ea, at its minimum design concentration of 7.0% v/v, is effective at extinguishing fires typical of those expected to occur in electronic data processing (EDP) facilities, telecommunication facilities and anechoic chambers. The levels of HF produced following extinguishment of typical Class a fires with HFC-227ea were well below the estimated mammalian LC50 and the human Dangerous Toxic Load (DTL), and do not appear to present a threat to electronic equipment.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 219-224 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Sandia National Laboratories (Sandia) has refined a process for developing inherently safer system designs based on methods used by Sandia to design detonation safety into nuclear weapons. The process was created when Sandia realized that standard engineering practices did not provide the level of safety assurance necessary for nuclear weapon operations, with their potential for catastrophic accidents. A systematic approach, which relies on mutually supportive design principles integrated through fundamental physical principles, was developed to ensure a predictably safe system response under a variety of operational and accident-based stesses. Robust, safe system designs result from this thematic approach to safety, minimizing the number of safety critical features. This safety assurance process has two profound benefits: the process avoids the need to understand or limit the ultimate intensity of off-normal environments and it avoids the requirement to analyze and test a large array of accident environment scenarios (e.g., directional threats, sequencing of environments, time races, etc) to demonstrate conformance to all safety requirements.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998) 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 233-237 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A new method is described to enhance the management of process safety risks such that the number and type of safety systems protecting against any hazard are consistently predicated upon risk. Further, that such an assignment of safety systems can be made consistent throughout an organization. This consistency is gained through standardization of qualitative risk ranking and by setting company guidelines.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 243-258 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Research was carried out to develop improved protection guidelines for silane handling systems through enhanced understanding of the behavior of releases of this pyrophoric gas. The approach involved addressing three aspects of the problem: the prompt ignition behavior of silane; the reactivity characteristics of quiescent silane/air mixtures; and the rates of reaction of silane leaked into enclosures with and without explosion venting, in the presence of ventilation air flow. A first conclusion, reached from tests in a ventilated cabinet, was that, contrary to prevailing belief, the ventilation flow has no measurable effect on the prompt ignition of the release. From experiments in a 5.1-liter (311-in.3) sphere it was found that silane/air mixtures of concentrations between 1.4 and 4.1% (by volume) are explosive but stable. In this case, piloted ignition tests yielded laminar burning velocities up to 5 m/s (1000 ft/min). Mixtures between 4.5 and 38% (the maximum reached in the tests) were found to be metastable, and would undergo spontaneous ignition after a delay ranging from 15 to 120 seconds, with the shorter values corresponding to higher silane concentrations. Experiments were also performed in a 0.645-m3 (22.8-ft3) vessel both with and without explosion venting, to measure the rates of energy release associated with impulsively-started silane leaks from 1/8 and 1/4-in. (3.2 and 6.4-mm) lines. A method for the prediction of the venting requirements of partial-volume deflagrations (PVD) was evolved into a tool to quantify the pressure rise from ignition of silane leaks in enclosures. These results represent a significant step toward updating existing design recommendations which prescribe ventilation requirements that are based on outdated and, in some instances, misinterpreted data.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Process Safety Progress 17 (1998), S. 278-287 
    ISSN: 1066-8527
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Gas explosion simulators are often used as tools in process plant design. This article presents some properties of gas explosions found using the EXSIM simulation software on three offshore modules with a total of nearly 10,000 simulations. The selected results are chosen for their supposed applicability to structural design in the process industries.Generalized data are presented for the effect of gas cloud size, explosion impulse vs. explosion pressure, pressure and impulse vs. duration, the probability of a “short” explosion, loading rate, pressure-time “shape” function, and the effect of introducing louvers.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 26 (1998), S. 155-159 
    ISSN: 0142-2421
    Keywords: XPS ; x-ray photoelectron spectroscopy ; ESR ; electron spin resonance ; Mo 3d ; Mo 3p ; O 1s ; binding energies ; Mo(IV) ; Mo(V) ; Mo(VI) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: There has been a longstanding debate and controversy in the literature with regard to the determination by XPS of the exact oxidation state of a molybdenum species commonly observed in the passive films of stainless steel. In this paper we have compared both the XPS and ESR analyses of molybdenum oxyhydroxides previously postulated to contain Mo(V) as well as Mo(IV) and Mo(VI). The compositions of these compounds closely resemble those found in the passive films of Mo-bearing stainless steel. It has been shown that the same Mo species exhibiting an XPS Mo 3d5/2 spectrum binding energy value of 230.8 eV is observed to exhibit an ESR spectra having a g factor of 1.921, which corresponds to Mo(V). © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 287-295 
    ISSN: 0749-503X
    Keywords: Candida maltosa ; Candida albicans ; tRNA splicing gene ; silent genes ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The tRNA splicing gene SPL1-1 has been cloned and sequenced in Saccharomyces cerevisiae (Kolman and Soll, 1993). Sequence adjacent to the LEU2 gene in Candida maltosa showed some homology to the SPL1-1 gene of S. cerevisiae. This work describes the sequencing of the SPL1 tRNA splicing genes from C. maltosa and C. albicans and the analysis of these genes. Comparison of these sequences and the relationship observed between the LEU2 and SPL1 genes in these yeasts suggests that there may be some synteny amongst various species of yeasts. The coding region of the C. maltosa SPL1 region described in this work differs from previously described partial sequences in that it is a complete uninterrupted open reading frame. Two strains of C. maltosa were each shown to contain different alleles, one uninterrupted open reading frame and one disrupted open reading frame. The sequences have been deposited in the GenBank/EMBL data libraries under Accession Numbers X72940, AF000115, AF000116, AF000117, AF000118, AF000119 and AF000120. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    ISSN: 0749-503X
    Keywords: Oligotrophic yeasts ; low-nutrient conditions ; starvation ; Cryptococcaceae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Seven oligotrophic yeasts, which can grow in a 104-fold dilution of malt-yeast-glucose-peptone medium (10-4 YM), were mainly isolated from soil. These yeasts belong to the Cryptococcaceae. When inoculated at about 102 cells/ml in 10-4 YM, the isolates grew to 1·4×103-2·4×105 cells/ml after 3 days. Some culture collection yeasts fell into three groups according to their growth characteristics in 10-4 YM, one group showing characteristics of the oligotrophic yeasts. The half-saturation values of uptake by the five isolated oligotrophic yeasts for D-glucose, L-leucine and L-amino acids were 6·0-25·0, 1·7-43·3 and 3·5-21·6 μM, respectively. The oligotrophic yeasts suspended in 10 mM-phosphate buffer (pH 6·0) had high tolerances for starvation, and remained more than 15% viable after 90 days of starvation. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; mitochondria ; mitochondrial matrix ; homo-oligomeric protein ; Mam33p ; gene disruption ; gC1q-R ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Mam33p (mitochondrial acidic matrix protein) is a soluble protein, located in mitochondria of Saccharomyces cerevisiae. It is synthesized as a precursor with an N-terminal mitochondrial targeting sequence that is processed on import. Mam33p assembles to a homo-oligomeric complex in the mitochondrial matrix. It can bind to the sorting signal of cytochrome b2 that directs this protein into the intermembrane space. Mam33p is encoded by an 801 bp open reading frame. Gene disruption did not result in a significant growth defect. Mam33p exhibits sequence similarity to gC1q-R, a human protein that has been implicated in the binding of complement factor C1q and kininogen. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    ISSN: 0749-503X
    Keywords: phosphofructokinase-1 ; Saccharomyces cerevisiae ; deletion mutants ; reactivation ; assembly ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Phosphofructokinase-1 from Saccharomyces cerevisiae is an octameric enzyme comprising two non-identical subunits, α and β, which are encoded by the unlinked genes PFK1 and PFK2. In this paper, assembly and reactivation of the enzyme have been studied in cell-free extracts of single-deletion mutants. In contrast to the previously described lack of phosphofructokinase-1 activity in cell-free extracts of these mutants, we could measure a temporary enzyme activity immediately after lysis of protoplasts. This result supports the assumption that each of the subunits forms an enzyme structure which is active in vivo but not stable after cell disruption.Upon mixing of separately prepared cell-free extracts of both deletion mutants very low activity could be measured. About 40% of the wild-type activity was regained when both mutants were mixed prior to disruption. The reactivation rate could be slightly increased by addition of ATP and fructose 6-phosphate and was found to be a function of the growth state, particularly of the β-subunit-carrying cells. The individual subunits did not interact with Cibacron Blue F3G-A, a biomimetic ligand of phosphofructokinase-1. After reassembly of both subunits in vitro a strong affinity of the reconstituted phosphofructokinase-1 to the dye-ligand was observed.The inability of the subunits to reconstitute under certain conditions seems to result from alterations of the intracellular environment following disruption. These changes give rise to induce an unproductive side reaction like self-aggregation of the subunits.Because reconstitution of phosphofructokinase-1 from S. cerevisiae behaves in a similar way to that of hemoglobin and luciferase, we would speculate a general mechanism for assembly of oligomeric proteins in vivo. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    ISSN: 0749-503X
    Keywords: Saccharomyces ; redox ; glycerol ; NADH ; shuttle ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Maintenance of a cytoplasmic redox balance is a necessity for sustained cellular metabolism. Glycerol formation is the only way by which Saccharomyces cerevisiae can maintain this balance under anaerobic conditions. Aerobically, on the other hand, several different redox adjustment mechanisms exist, one of these being the glycerol 3-phosphate (G3P) shuttle. We have studied the importance of this shuttle under aerobic conditions by comparing growth properties and glycerol formation of a wild-type strain with that of gut2Δ mutants, lacking the FAD-dependent glycerol 3-phosphate dehydrogenase, assuming that the consequent blocking of G3P oxidation is forcing the cells to produce glycerol from G3P. To impose different demands on the redox adjustment capability we used various carbon sources having different degrees of reduction.The results showed that the shuttle was used extensively with reduced substrate such as ethanol, whereas the more oxidized substrates lactate and pyruvate, did not provoke any activity of the shuttle. However, the absence of a functional G3P shuttle did not affect the growth rate or growth yield of the cells, not even during growth on ethanol. Presumably, there must be alternative systems for maintaining a cytoplasmic redox balance, e.g. the so-called external NADH dehydrogenase, located on the outer side of the inner mitochondrial membrane. By comparing the performance of the external NADH dehydrogenase and the G3P shuttle in isolated mitochondria, it was found that the former resulted in high respiratory rates but a comparably low P/O ratio of 1·2, whereas the shuttle gave low rates but a high P/O ratio of 1·7.Our results also demonstrated that of the two isoforms of NAD-dependent glycerol 3-phosphate dehydrogenase, only the enzyme encoded by GPD1 appeared important for the shuttle, since the enhanced glycerol production that occurs in a gut2Δ strain proved dependent on GPD1 but not on GPD2. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    ISSN: 0749-503X
    Keywords: modified LFH cassette ; EUROFAN 6-pack analysis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Six open reading frames (ORFs) of unknown function from Saccharomyces cerevisiae chromosome XV, three from the left and three from the right arm, were deleted in two diploid strains by the short flanking homology method (Wach et al., 1994). Transformants were selected as Geneticin (G418)-resistant colonies and correct integration of the kanMX4 cassette was checked by colony PCR. Following sporulation of the diploids, tetrads were dissected and scored for the segregation of the G418-resistant marker. We have developed a widely applicable method for the construction of gap repair plasmids to obtain the cognate clones for each of the disrupted ORFs. The 5′- and 3′-flanks of the ORF in question are linked by a unique restriction endonuclease. When the plasmid is cut at this site it can be used to obtain, by selection for the appropriate antibiotic resistance, long flanking homology (LFH) cassettes containing the cognate clone or the disrupted allele. The LFH cassette containing the cognate clone or the disrupted allele can be released from the gap-repaired plasmid by cutting at the inserted flanking restriction sites. One of the six ORFs (YOR319w) corresponds to an essential gene whose product is part of the spliceosome complex. Haploid as well as homozygous and heterozygous diploid disruptant strains for each of the five non-essential ORFs were subjected to growth test on different media at 15°C, 30°C and 37°C. Disruption of YOR322c causes osmotically sensitive growth on YEPD at 37°C and the product of YOL091w appears to play a role in sporulation since the homozygous diploid disruptant has lost the ability to sporulate. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 409-417 
    ISSN: 0749-503X
    Keywords: transcription factor ; SPT3 sequences ; Schizosaccharomyces pombe ; Kluyveromyces lactis ; Clavispora opuntiae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Spt3 of Saccharomyces cerevisiae is a factor required for normal transcription from particular RNA polymerase II-dependent promoters. As a step towards analysing Spt3 structure-function relationships, we have identified and studied Spt3 homologues from three other yeasts: Kluyveromyces lactis, Clavispora opuntiae and Schizosaccharomyces pombe. Alignment of their predicted amino acid sequences shows an overall identity of 30% between all four homologues and suggests that three conserved domains are present in Spt3. When tested for function in S. cerevisiae, K. lactis SPT3 was shown to fully complement and S. pombe SPT3 to partially complement an spt3 Δ mutation. These data demonstrate that Spt3 is functionally conserved among distantly related yeasts. The new sequences have been entered in GenBank: AF005930 (K. lactis SPT3), AF005932 (C. opuntiae SPT3) and AF005931 (S. pombe SPT3). © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 471-477 
    ISSN: 0749-503X
    Keywords: ribosomal protein genes ; yeast genome ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Screening of the complete genome sequence from the yeast Saccharomyces cerevisiae has enabled us to compile a complete list of the genes encoding cytoplasmic ribosomal proteins in this organism.Putative ribosomal protein genes were selected primarily on the basis of the sequence similarity of their products with ribosomal proteins from other eukaryotic organisms, in particular the rat. These genes were subsequently screened for typical yeast rp-gene characteristics, viz. (1) a high codon adaptation index; (2) their promoter structure and (3) their responses to changes in growth conditions.The yeast genome appears to carry 78 different genes, of which 59 are duplicated, encoding 32 different small-subunit and 46 large-subunit proteins. A new nomenclature for these ribosomal proteins is proposed. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 335-345 
    ISSN: 0749-503X
    Keywords: Candida albicans ; arginine permease ; amino acid transport ; affinity chromatography ; functional reconstitution ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have for the first time purified arginine permease from a pathogenic yeast, Candida albicans, to homogeneity by affinity chromatography using L-arginine-linked agarose matrix as affinity column. The purified protein (PP) was of 66 kDa with no subunit structure. Two kinetically distinct binding affinities of PP were evident where high affinity binding (S1) revealed a dependence on acidic pH while pH did not have dramatic effect on low affinity (S2) binding. The specificity of L-arginine binding to PP with regard to other amino acids, structural analogues and inhibitors, was essentially similar to arginine transport observed in the intact cells of C. albicans (Rao et al., 1986). The purified arginine permease was reconstituted into proteoliposomes and its functionality was tested by imposing a valinomycin-induced membrane potential. All the characteristic features of L-arginine transport displayed by the reconstituted system were similar to those observed in intact cells. Thus homogeneous purified arginine permease was also functionally active. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    ISSN: 0749-503X
    Keywords: polyphosphatase ; cytosol ; yeast ; purification ; kinetic model ; Mg2+ ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A homogenous polyphosphatase preparation was obtained from Saccharomyces cerevisiae cytosol with a 3·8% yield and 3540-fold purification. The enzyme hydrolysed polyphosphate (polyP) with various chain lengths, including polyP3, and split Pi off the end of the chain. It was inactive with respect to ATP, PPi, and p-nitrophenylphosphate. Its specific activity with polyP15 was 283 U/mg protein. The polyphosphatase was a monomeric protein with a molecular mass of 40 kDa. This enzyme was inactive without divalent cations and with Cu2+ and Ca2+. The ability of other divalent cations to activate the enzyme decreased in the following order: Co2+〉Mn2+〉Mg2+〉Zn2+. A kinetic model of the hydrolysis of polyP3 and action of Mg2+ is proposed. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 401-407 
    ISSN: 0749-503X
    Keywords: yeast ; Kluyveromyces marxianus ; malic acid transport ; mutants ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In malic acid-grown cells of the strains ATCC 10022 and KMS3 of Kluyveromyces marxianus the transport of malic acid occurred by a malate-proton symport, which accepted l-malic, d-malic, succinic and fumaric acids, but not tartaric, malonic or maleic acids. The system was inducible and subjected to glucose repression. Mutants of the strain KMS3, unable to grow in a medium with malic acid, were isolated and checked for their capacity to utilize several carbon sources and to transport dicarboxylic acids by the malate-proton symport. Two distinct clones affected on malate transport were obtained. Both were able to grow on a medium with glycerol or ethanol but not with dl-malic, succinic, oxoglutaric and oxaloacetic acids as the sole carbon and energy sources. However, while one of the mutants (Mal7) displayed activity levels for the enzymes malate dehydrogenase, isocitrate lyase, and phosphoenolpyruvate carboxykinase similar to those of the wild strain, in the other mutant type (Mal6) the activities for the same enzymes were significantly reduced. Plasma membranes from derepressed cells of the wild strain and of the mutants Mal6 and Mal7 were isolated and the protein analysed by SDS-PAGE. The electrophoretic patterns of these preparations differed in a polypeptide with an apparent molecular mass of about 28 kDa, which was absent only in the mutant Mal7. The results indicated that Mal7 can be affected in a gene that encodes a malate carrier in K. marxianus. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 485-492 
    ISSN: 0749-503X
    Keywords: Schizosaccharomyces pombe ; protein kinase ; cell flocculation ; PRK1 ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We report the isolation and characterization of a protein kinase from the fission yeast Schizosaccharomyces pombe. The proposed Prk1 protein contains 352 amino acids and has significant homology to the Ume5p kinase (also known as Srb10p, Ssn3p and Are1p) of the budding yeast Saccharomyces cerevisiae, a cyclin-dependent kinase involved in regulating the transcription of a diverse set of genes. Disruption of the prk1 gene increases flocculation but does not appear to have any other significant effect on cell behaviour. This defect can be overcome by expressing the UME5 gene, indicating that Prk1 is the fission yeast homologue of Ume5p. The sequence is in the EMBL data library under Accession Number Z98977. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 431-442 
    ISSN: 0749-503X
    Keywords: differential display ; S.cerevisiae ; thermotolerance ; repression ; derepression ; gene regulation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have described the use of differential display of PCR-amplified reverse transcribed mRNA (DDRT-PCR) to survey changes in gene expression profiles induced by heat shock and carbon catabolite derepression in Saccharomyces cerevisiae. It is well established that either of these states elicits thermotolerant phenotypes. An initial analysis conducted on cells of an inherently thermosensitive strain (Ysen) indicated that approximately 10% of the total number of cDNAs detected were either up or down regulated following heat shock at 37°C (30 min) in comparison to control cells (25°C). In addition, whereas 7% of all PCR products were preferentially expressed during derepressive growth, approximately 2% were found to be common to both heat-shocked and derepressed cells. A repeat analysis, performed on all three cell types of Ysen as well as cells of a relatively thermoresistant strain (Yres) yielded 30 differentially displayed cDNA fragments common to heat-shocked and derepressed cells of both strains. Eighteen of these generated signals on Northern blots, of which three were confirmed as regulated. Five amplicons, including one not detected by Northern analysis and another from the derepressed state, were cloned and sequenced. Three of these exhibited homology to S. cerevisiae genes with well-characterized protein products: HSP 90, HXK1and STA1. The remaining two applicons showed nucleotide identity to YTIS11, a homolog of the mammalian TIS11 and putative transcriptional activator, and an orphan gene encoding a hypothetical transmembrane protein belonging to the multi-drug resistance translocase family. Our novel application of DDRT-PCR has identified new and known genes that may be further evaluated as factors involved in stress regulation and has demonstrated the potential of the technique to systematically analyse gene expression in yeast. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 583-586 
    ISSN: 0749-503X
    Keywords: Saccharomyces exiguus ; STE3 ; homolog ; sequence analysis ; differentiation of species ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Homologs of Saccharomyces cerevisiae STE3, a-factor receptor gene were detected from S. exiguus NFRI 3539 by low stringency Southern hybridization. This strain might have at least two types of homolog. One of these homologs, designated as e-STE3 was cloned. Its nucleotide sequence revealed 60% identity to STE3. The putative protein coding region consisted of 453 amino acid residues. The amino acid sequence identity between STE3 and e-STE3 was 62%, and that of the N-terminal 303 amino acid residues considered to be the pheromone binding domain was 79%. The e-STE3 sequence submitted to the DDBJ/EMBL/GenBank data libraries is available under Accession Number AB003086. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 565-571 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; electroporation ; transformation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Pretreatment of yeast cells with lithium acetate (LiAc) and dithiothreitol (DTT) enhances the frequency of transformation by electroporation. The method shows improvements of 6-67-fold in wild-type strains derived from commonly used Saccharomyces cerevisiae genetic backgrounds. In addition, 15-300-fold improvement in transformation frequency was achieved with several mutant strains of S. cerevisiae that transformed poorly by conventional procedures. Both DTT and lithium acetate were necessary for maximal transformation frequencies. Pretreatment with lithium and DTT also resulted in an ∼3·5-fold increase in the electroporation transformation frequency of the pathogenic fungus Candida albicans. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    ISSN: 0749-503X
    Keywords: multidrug resistance ; CDR1 ; ABC transporter ; baculovirus expression ; C. albicans ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Cdr1p, an ATP-binding cassette transporter from the pathogenic yeast Candida albicans, confers resistance to several unrelated drugs including anti-Candida drugs (Prasad et al., 1995b). We demonstrate that the deletion of 237 bp (79 aa) from the 3′ end of CDR1 (which encompasses the transmembrane domain (TM) 12 of the putative transporter) did not result in the total loss of its ability to efflux cytotoxic agents. While the expression of ΔCDR1 in yeast resulted in impaired sensitivity to drugs like cycloheximide, anisomycin, sulfomethuron methyl and antifungal nystatin, its ability to confer resistance remained unaltered to drugs such as o-phenanthroline, 4-nitroquinoline-N-oxide, cerulenin, azoles, oligomycin, erythromycin, and benomyl. Similar to human MDR1p, Cdr1p might also have localized drug binding sites in TM 12, but that might not be the case for all the drugs. The TM 12 deletion also did not lead to any significant impairment in NTPase activities. Both ATPase and UTPase activities of complete Cdr1p and ΔCdr1p were not significantly altered, as was the case with respect to their ability to efflux Rh123 and steroid hormone like [3H]-β-estradiol. To further dissect the functionality of Cdr1p, its truncated version was overexpressed in a baculovirus-insect cell expression system. The synthesis of ΔCdr1p in Sf9 cells was temporally regulated as a function of the baculovirus polyhedrin gene promoter. The Sf9 derived ΔCdr1p was ∼130 kDa, which was lower than the expected size, probably due to the differences in glycosylation. This, however, did not affect the functionality of ΔCdr1p. The deletion of TM 12 did not affect the targeting of the protein and ΔCdr1p was exclusively localized in plasma membrane of Sf9 cells as detected by immunofluorescence. The expression of ΔCdr1p in the baculovirus-insect expression system generated a high drug-stimulated plasma membrane-bound ATPase activity which was not demonstrable when ΔCdr1p was expressed in yeast. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 869-875 
    ISSN: 0749-503X
    Keywords: calmodulin ; CMD1 ; ALG1 ; K. lactis ; EF hand ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The KlCMD1 gene was isolated from a Kluyveromyces lactis genomic library as a suppressor of the Saccharomyces cerevisiae temperature-sensitive mutant spc110-124, an allele previously shown to be suppressed by elevated copy number of the S. cerevisiae calmodulin gene CMD1. The KlCMD1 gene encodes a polypeptide which is 95% identical to S. cerevisiae calmodulin and 55% identical to calmodulin from Schizosaccharomyces pombe.Complementation of a S. cerevisiae cmd1 deletion mutant by KlCMD1 demonstrates that this gene encodes a functional calmodulin homologue. Multiple sequence alignment of calmodulins from yeast and multicellular eukaryotes shows that the K. lactis and S. cerevisiae calmodulins are considerably more closely related to each other than to other calmodulins, most of which have four functional Ca2+-binding EF hand domains. Thus like its S. cerevisiae counterpart Cmd1p, the KlCMD1 product is predicted to form only three Ca2+-binding motifs. The KlCMD1 sequence has been assigned Accession Number AJ002021 in the EMBL/GenBank database. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; adrenodoxin reductase ; mitochondria ; essential gene ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A yeast gene was found in which the derived protein sequence has similarity to human and bovine adrenodoxin reductase (Nobrega, F. G., Nobrega, M. P. and Tzagoloff, A. (1992). EMBO J. 11, 3821-3829; Lacour, T. and Dumas, B. (1996). Gene 174, 289-292), an enzyme in the mitochondrial electron transfer chain that catalyses in mammals the conversion of cholesterol into pregnenolone, the first step in the synthesis of all steroid hormones. It was named ARH1 (Adrenodoxin Reductase Homologue 1) and here we show that it is essential. Rescue was possible by the yeast gene, but failed with the human gene. Supplementation was tried without success with various sterols, ruling out its involvement in the biosynthesis of ergosterol. Immunodetection with a specific polyclonal antibody located the gene product in the mitochondrial fraction. Consequently ARH1p joins the small group of gene products that affect essential functions carried out by the organelle and not linked to oxidative phosphorylation. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 633-646 
    ISSN: 0749-503X
    Keywords: genetic interaction ; membrane traffic ; retrograde transport ; docking complex ; coatomer ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Tip20p is an 80 kDa cytoplasmic protein bound to the cytoplasmic surface of the endoplasmic reticulum (ER) by interaction with the type II integral membrane protein Sec20p. Both proteins are required for vesicular transport between the ER and Golgi complex. Recently, sec20-1 was found to be defective in retrograde transport. A collection of temperature-sensitive tip20 mutants are shown to be lethal in combination with ufe1-1, a target SNARE of the ER and ret2-1, yeast δ-COP. A subset of tip20 mutants was found to be lethal in combination with sec20-1, sec21-1, sec22-3 and sec27-1. Since all pairwise combinations of a tip20 mutant, sec20-1, and ufe1-1 are lethal, Tip20p and Sec20p might be part of the docking complex for Golgi-derived retrograde transport vesicles. Since carboxy-terminal tip20 truncations are lethal in combination with mutants in three coatomer subunits, Tip20p might be involved in binding or uncoating of COPI coated retrograde transport vesicles. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    ISSN: 0749-503X
    Keywords: heat shock ; protein-DNA interactions ; transcriptional regulation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The C-terminal hydrophobic repeat (CTR) of heat shock transcription factor (HSF) has been proposed to regulate DNA binding by intramolecular interactions with the leucine zipper motifs present in the HSF trimerization domain. Schizosaccharomyces pombe provides a useful model organism for the study of the regulation of HSF DNA binding because, unlike Saccharomyces cerevisiae, S. pombe hsf is highly heat shock inducible for DNA binding and contains a clear homology to the CTR. We examined the role that the CTR plays in the regulation of S. pombe hsf by constructing isogenic strains bearing deletion and point mutations in the chromosomal copy of hsf. Surprisingly, we found that point mutation of key hydrophobic amino acids within the CTR, as well as full deletion of it, yielded factors that show normal binding at normal growth temperatures and full levels of heat-induced binding. Deletion of the CTR did, however, slightly lower the temperature required for maximal activation. In contrast, a large deletion of the C-terminus, which removes close to a third of the coding sequence, was deregulated and bound DNA at control temperature. Several of the deletion mutants were significantly reduced in their level of expression, yet they showed wild-type levels of DNA binding activity following heat shock. These experiments demonstrate that appropriate regulation of the DNA binding activity of S. pombe hsf is not solely dependent upon the CTR, and imply that a feedback mechanism exists that establishes proper levels of DNA binding following heat shock despite mutations that significantly alter levels of total hsf. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 747-757 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; ubiquitin carrier proteins ; cyclin degradation ; functional analysis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: UBC11 is the Saccharomyces cerevisiae gene that is most similar in sequence to E2-C, a ubiquitin carrier protein required for the destruction of mitotic cyclins and proteins that maintain sister chromatid cohesion in animal cells and in Schizosaccharomyces pombe. We have disrupted the UBC11 gene and found it is not essential for yeast cell viability even when combined with deletion of UBC4, a gene that has also been implicated in mitotic cyclin destruction. Ubc11p does not ubiquitinate cyclin B in clam cell-free extracts in vitro and the destruction of Clb2p is not impaired in extracts prepared from Δubc11 or Δubc4Δubc11 cells. These results suggest Ubc4p and Ubc11p together are not essential for mitotic cyclin destruction in S. cerevisiae and we can find no evidence to suggest that Ubc11p is the true functional homologue of E2-C. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    ISSN: 0749-503X
    Keywords: Candida albicans ; HIS4 ; complementation ; molecular biology tools ; topological marker ; amino acid biosynthesis general control ; PEX5 ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have isolated the Candida albicans HIS4 (CaHIS4) gene by complementation of a his4-34 Saccharomyces cerevisiae mutant. The sequenced DNA fragment contains a putative ORF of 2514 bp, whose translation product shares a global identity of 44% and 55% to the His4 protein homologs of S. cerevisiae and Kluyveromyces lactis, respectively. Analysis of CaHIS4 sequence suggests that, similarly to S. cerevisiae HIS4, it codes for a polypeptide having three separate enzymatic activities (phosphoribosyl-AMP cyclohydrolase, phosphoribosyl-ATP pyrophosphohydrolase and histidinol dehydrogenase) which reside in different domains of the protein. A C. albicans his4 strain is complemented with this gene when using a C. albicans-S. cerevisiae-Escherichia coli shuttle vector, thus enabling the construction of a host system for C. albicans genetic manipulation. In addition, upstream of the sequenced CaHIS4 sequence, we have found the 3′-terminal half of a gene encoding a PEX5-like protein. The EMBL/DDJB/GenBank Accession Number of this sequence is AJ003115. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    ISSN: 0749-503X
    Keywords: yeast ; elongation factor-3 ; EF-3 ; homolog ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A paralog (intraspecies homolog) of the Saccharomyces cerevisiae YEF3 gene, encoding elongation factor-3, has been sequenced in the course of the yeast genome project, and identified by database searching; this gene has been designated HEF3. Bioinformatic and Northern blot analysis indicate that the HEF3 gene is not expressed during vegetative growth. Deletion of the HEF3 gene reveals no growth defects, nor any defects in mating or sporulation. A high copy 2μ clone of HEF3 was constructed, and was shown to be unable to complement a null allele of yef3. Finally, an in vitro assay for ribosome-stimulated ATPase activity was performed with isogenic HEF3 and Δhef3 strains; no difference in biochemical activity could be detected in these strains. From these results, we conclude that the HEF3 gene does not encode a functional homolog of YEF3. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 1115-1125 
    ISSN: 0749-503X
    Keywords: Yarrowia lipolytica ; secretion ; pH ; extracellular protease ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The secretion and maturation of the acid extracellular protease (AXP) of the yeast Yarrowia lipolytica have been characterized using antiserum raised against this enzyme. A 42 kDa pro-enzyme form of AXP was identified from lysates of radiolabelled Y. lipolytica cells and found to contain no N-linked carbohydrate moieties. Using pulse-chase immune precipitation it was demonstrated that the AXP precursor was secreted into the extracellular medium where, under conditions of low pH, it underwent autocatalytic activation forming the mature enzyme. Conversion of the AXP pro-form in the presence of the protease inhibitor pepstatin indicated that an intramolecularly-catalysed reaction mechanism was involved in AXP maturation. Further evidence supporting the role of autocatalytic processing came from the side-chain specificity of mature AXP towards the oxidized B-chain of insulin. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    ISSN: 0749-503X
    Keywords: cell walls ; protease ; β-glucanase ; lysis ; yeast ; antifungal drugs ; glucan ; mannoprotein ; S. cerevisiae ; C. albicans ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The rate of formation of spheroplasts of yeast can be used as an assay to study the structural integrity of cell walls. Lysis can be measured spectrophotometrically in hypotonic solution in the presence of Zymolyase, a mixture of cell wall-digesting enzymes. The optical density of the cell suspension decreases as the cells lyse. We optimized this assay with respect to enzyme concentration, temperature, pH, and growth conditions for several strains of Saccharomyces cerevisiae. The level of variability (standard deviation) was 1-5% between trials where the replications were performed on the same culture using enzyme prepared from the same lot, and 5-15% for different cultures of the same strain. This assay can quantitate differences in cell wall structure (1) between exponentially growing and stationary phase cells, (2) among different S. cerevisiae strains, (3) between S. cerevisiae and Candida albicans, (4) between parental and mutated lines, and (5) between drug- or chemically-treated cells and controls. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    ISSN: 0749-503X
    Keywords: carbocyanine fluorescent probes ; membrane potential ; yeast ; cell wall ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Membrane-potential-dependent accumulation of diS-C3(3) in intact yeast cells in suspension is accompanied by a red shift of the maximum of its fluorescence emission spectrum, λmax, caused by a readily reversible probe binding to cell constituents. Membrane depolarization by external KCl (with or without valinomycin) or by ionophores causes a fast and reproducible blue shift. As the potential-reporting parameter, the λmax shift is less affected by probe binding to cuvette walls and possible photobleaching than, for example, fluorescence intensity. The magnitude of the potential-dependent red λmax shift depends on relative cell-to-probe concentration ratio, a maximum shift (572→582 nm) being found in very thick suspensions and in cell lysates. The potential therefore has to be assessed at reasonably low cell (≤5×106 cells/ml) and probe (10-7 M) concentrations at which a clearly defined relationship exists between the λmax shift and the potential-dependent accumulation of the dye in the cells. The redistribution of the probe between the medium and yeast protoplasts takes about 5 min, but in intact cells it takes 10-30 min because the cell wall acts as a barrier, hampering probe penetration into the cells. The barrier properties of the cell wall correlate with its thickness: cells grown in 0·2% glucose (cell wall thickness 0·175±0·015 μm, n=30) are stained much faster and the λmax is more red-shifted than in cells grown in 2% glucose (cell wall thickness 0·260±0·043 μm, n=44). At a suitable cell and probe concentration and under standard conditions, the λmax shift of diS-C3(3) fluorescence provides reliable information on even fast changes in membrane potential in Saccharomyces cerevisiae. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    ISSN: 0749-503X
    Keywords: critical target model ; differential scanning calorimetry ; Saccharomyces cerevisiae ; heat-shock response ; acquired thermotolerance ; thermal stability ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Hyperthermic cell killing profiles of Saccharomyces cerevisiae cells were biphasic and a shoulder (phase 1) was followed by an exponential killing (phase 2). Assuming that (i) the rate of thermal damage in particular macromolecules or their assemblies limits the rate of hyperthermic cell killing (the critical target model), and (ii) the damages of two families of targets are lethal independently, we built a ‘dual critical target model’ in order to interpret the biphasic cell killing.Time-courses of temperature-programmed fractional survival were traced for S. cerevisiae cells in exponentially growing phase, heat shocked, and in stationary phase. Non-linear curve-fitting of the time-courses by using the dual critial target model provided the Arrhenius parameters of denaturation of the two families of targets. The cells were killed more slowly in phase 1 than in phase 2. Arrest in stationary phase, not heat shock, stabilizes the family of targets that is critical to phase 1 death. On the other hand, both heat-shock response and arrest in stationary phase stabilizes the other family of targets that, in addition to the previous one, is responsible for phase 2 death. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    ISSN: 0749-503X
    Keywords: Dipodascus (Endomyces) magnusii ; genetic transformation ; ribosomal DNA ; autonomous replicating sequence ; electroporation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have developed the first system for genetic transformation of the multinuclear yeast Dipodascus magnusii. The system is based on a dominant selectable marker and an autonomously replicating sequence. We have constructed a plasmid vector which contains a marker conferring resistance to zeocin and the segment of non-transcribed spacer of D. magnusii ribosomal DNA which supports the autonomous replication of plasmid DNA in yeast cells. Plasmid DNA has been transferred into D. magnusii cells by electroporation. The DNA sequence which is described in this article has been deposited in the EMBL data library under Accession Number Y14587. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 847-852 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; 2 micron plasmid ; Flp ; DNA damage ; curing ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Powerful mutagenic screens of yeast Saccharomyces cerevisiae have recently been developed which require strains that lack the endogenous 2 micron plasmid (Burns et al., 1994). Here, we describe a simple and reliable method for curing yeast of the highly stable genetic element. The approach employs heterologous expression of a ‘step-arrest’ mutant of the Flp recombinase. The mutant, Flp H305L (Parsons et al., 1988), forms long-lived covalent protein-DNA complexes exclusively at 2 micron-borne recombinase target sites. In vivo, the complexes serve as sites of targeted DNA damage. Using Southern hybridization and a colony color assay for plasmid loss, we show that expression of the mutant enzyme results in the effective elimination of the 2 micron from cells. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 985-1000 
    ISSN: 0749-503X
    Keywords: Mig1 repressor ; glucose repression ; Saccharomyces cerevisiae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A major mediator of glucose repression in yeast is Mig1, a zinc finger protein that binds to a GC-rich recognition sequence found upstream of many glucose-repressible genes. Because these Mig1 sites are found upstream of genes under different modes of regulation, we studied regulation of transcription mediated by an isolated Mig1 site placed upstream of a reporter gene under control of UASCYC1. The Mig1 site responded appropriately to glucose control and regulatory mutations, including snf1, reg1, cyc8, and tup1, mimicking the behavior of the SUC2 gene. Deletion of the MIG1-coding gene reduced but did not eliminate glucose repression mediated by the Mig1 site. Complete loss of repression was seen in a mig1 mig2 double mutant. When the UASCYC1 was replaced by UASADH1 in the reporter plasmid, the Mig1 site activated transcription under most conditions. Mutations of the two Mig1 binding sites in the SUC2 promoter resulted in loss of activation of SUC2 expression. These results suggest the presence of an unknown activator or activators that binds to the Mig1 site. The activator is not any of the proteins previously proposed to bind to this site, including Mig1, Mig2, Msn2, or Msn4. Band shift assays showed that Mig1 is the major protein in yeast cell extracts that binds to the Mig1 site in vitro. This binding is not regulated by glucose or mutations in CYC8 or TUP1. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 1001-1006 
    ISSN: 0749-503X
    Keywords: succinate dehydrogenase ; SDH1 ; SDH1b ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Transformation of the respiratory-defective mutant (E264/U2) of Saccharomyces cerevisiae with a yeast genomic library yielded two different plasmids capable of restoring the ability of the mutant to grow on non-fermentable substrates. One of the plasmids (pG52/T3) contained SDH1 coding for the flavoprotein subunit of mitochondrial succinate dehydrogenase. The absence of detectable succinate dehydrogenase activity in mitochondria of E264/U2 and the lack of complementation of the mutant by an sdh11null strain indicated a mutation in SDH1. The second plasmid (pG52/T8) had an insert with reading frame (YJL045w) of yeast chromosome X coding for a homologue of SDH1. Subclones containing the SDH1 homologue (SDH1b), restored respiration in E264/U2 indicating that the protein encoded by this gene is functional. The expression of the two genes was compared by assaying the β-galactosidase activities of yeast transformed with plasmids containing fusions of lacZ to the upstream regions of SDH1 and SDH1b. The 100-500 times lower activity measured in transformants harbouring the SDH1b-lacZ fusion indicates that the isoenzyme encoded by SDH1b is unlikely to play an important role in mitochondrial respiration. This is also supported by the absence of any obvious phenotype in cells with a disrupted copy of SDH1b. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; promoter-substitution cassette ; tetracycline-regulatable promoter ; essential genes ; conditional gene expression ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A promoter-substitution cassette has been constructed that allows one-step substitution of chromosomal gene promoters for the tetracycline-regulatable tetO promoter in yeast cells, which uses kanMX4 as selective marker for geneticin resistance. Oligonucleotides for PCR amplification of the cassette are designed to allow homologous recombination through short flanking regions of homology with the upstream sequences of the chromosomal gene, upon transformation of target cells. By testing three essential genes of chromosome XV (YOL135c, YOL142w and YOL144w), the system causes tetracycline-dependent conditional growth of the cells, being modulatable by intermediate concentrations of the effector. Analysis of terminal phenotypes of the promoter-substituted cells in the presence of the antibiotic may facilitate functional analysis of essential orphan genes. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    ISSN: 0749-503X
    Keywords: chemostat cultivation ; Saccharomyces cerevisiae ; carbon source ; transcriptional regulation ; UAS ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: To identify common regulatory sequences in the promoters of genes, transcription of 31 genes of Saccharomyces cerevisiae was analysed during the transient response to a glucose pulse in a chemostat culture. mRNA levels were monitored during the subsequent excess glucose, ethanol and acetate phases, while other conditions were kept constant. This setup allowed a direct comparison between regulation by glucose, ethanol and acetate.Genes with identical regulation patterns were grouped to identify regulatory elements in the promoters. In respect to regulation on glucose four classes were identified: no transcription under any of the conditions tested, no difference in regulation on glucose, induced on glucose and repressed on glucose. In addition, genes were found that were repressed or induced on ethanol or acetate. Sequence alignment of genes with similar regulation patterns revealed five new, putative regulatory promoter elements. (i) The glucose-inducible fermentation genes PDC1 and ADH1 share the sequence ATACCTTCSTT. (ii) Acetate-repression might be mediated by the decamer CCCGAG RGGA, present in the promoters of ACS2 and ACR1. (iii) A specific element (CCWTTSRNCCG) for the glyoxylate cycle was present in seven genes studied: CIT2, ICL1, MLS1, MDH2, CAT2, ACR1 and ACH1. These genes were derepressed on ethanol or acetate. (iv) The sequence ACGTSCRGAATGA was found in the promoters of the partially ethanol-repressed genes ACS1 and YAT1. (v) Ethanol induction, as seen for ACS2, ADH3 and MDH1, might be mediated via the sequence CGGSGCCGRAG. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    ISSN: 0749-503X
    Keywords: LFH deletion cassette ; functional analysis ; chromosome IV ; Saccharomyces cerevisiae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We report here the construction of six deletion mutants and the analysis of their basic phenotype. Deletion cassettes containing the KanMX4 marker module and long flanking regions homologous to the target locus were constructed for each of the six open reading-frames (ORFs YDL088c, YDL087c, YDL086w, YDL085w, YDL084w and YDL082w) located on chromosome IV. Sporulation and tetrad analysis of heterozygous deletant strains revealed that, in the FY1679 genetic background, ORFs YDL088c, YDL087c and YDL084w are essential genes for vegetative growth whereas YDL086w, YDL085w and YDL082w are non-essential. ydl088cΔ and ydl084wΔ haploid strains are viable in the CEN. PK2 genetic background although ydl084wΔ grows at a slower rate than the wild type. Complementation tests by corresponding cognate genes confirmed that gene inactivation was responsible for these growth defects. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    ISSN: 0749-503X
    Keywords: Candida boidinii ; peroxisome ; peroxisomal proliferation ; peroxisomal membrane proteins ; d-amino acid oxidase ; green fluorescent protein ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A methylotrophic yeast, Candida boidinii, was grown on various combinations of peroxisome-inducing carbon source(s) (PIC(s)), i.e. methanol, oleate and d-alanine, and the regulation of peroxisomal proteins (both matrix and membrane ones) and organelle proliferation were studied. This regulation was followed (1) at the protein or enzyme level by means of the peroxisomal enzyme activity and Western analysis; (2) at the mRNA level by Northern analysis; and (3) at the organelle level by direct observation of peroxisomes under a fluorescent microscope. Peroxisomal proliferation was followed in vivo by using a C. boidinii strain producing a green fluorescent protein having peroxisomal targeting signal 1. When multiple PICs were used for cell growth, C. boidinii induced specific peroxisomal proteins characteristic of all PIC(s) present in the medium, responding to all PIC(s) simultaneously. Thus, these PICs were considered to induce peroxisomal proliferation independently and not to repress peroxisomes induced by other PICs. Next, the sensitivity of the peroxisomal induction to glucose repression was studied. While the peroxisomal induction by methanol or oleate was completely repressed by glucose, the d-alanine-induced activities of d-amino acid oxidase and catalase, Pmp47, and the organelle proliferation were not. These results indicate that peroxisomal proliferation in yeasts is not necessarily sensitive to glucose repression. Lastly, this regulation was shown to occur at the mRNA level. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    ISSN: 0749-503X
    Keywords: anaplerotic reactions ; glyoxylate cycle ; catabolite repression ; Pichia ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have cloned and characterized a gene encoding pyruvate carboxylase from the methylotrophic yeast Pichia pastoris. Disruption of this gene produced inability to grow in minimal medium with glucose as carbon source and ammonium as nitrogen source. Growth was possible with aspartate or glutamate as nitrogen source. The gene PpPYC1 expressd from its own promoter was able to rescue the phenotype of Saccharomyces cerevisiae mutants devoid of pyruvate carboxylase.In a P. pastoris strain carrying a disrupted PpPYC1 gene we have isolated spontaneous mutants able to grow in non-permissive conditions. In a mutant strain grown in glucose several enzymes sensitive to catabolite repression were derepressed. The strain also had elevated levels of glutamate dehydrogenase (NAD) both in repressed and derepressed conditions. The sequence of the PpPYC1 gene has been entered in the EMBL nucleotide sequence databank: Accession Number Y11106. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    ISSN: 0749-503X
    Keywords: Chromosome length ; chromosome VI ; electrophoretic karyotype ; RFLP ; Saccharomyces ; saké yeast ; taxonomy ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Previous studies have revealed that chromosome VI of saké yeasts is much larger than that of the other strains of Saccharomyces cerevisiae. Southern analysis using segments of chromosome VI of a laboratory strain as probes suggested that the nucleotide sequence of a major portion of this chromosome is conserved, but considerable diversity was found in the distal parts in the other strains. Physical maps also indicated that differences in length of chromosome VI were mainly due to differences in its ends. NotI was found to generate 9 kb and/or 16 kb fragments from the left telomere of chromosome VI in most saké yeasts, but no fragment in the case of AB972. SfiI produced one or two 30-50 kb fragments from the right end of this chromosome in all saké yeasts tested, but produced a 20 kb fragment in the case of AB972. All S. cerevisiae strains not employed in saké brewing were the same as AB972 in these respects. S. paradoxus had one NotI site in chromosome VI, while S. bayanus had two, one of which is possibly common to both species. The SfiI site mentioned above was present in chromosome VI of all species, while that of S. bayanus and S. paradoxus each had a second site distinct from the other. Chromosome VI of S. pastorianus was not distinguishable from that of S. bayanus. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 861-867 
    ISSN: 0749-503X
    Keywords: HIS3 ; TRP1 ; IPP1 ; Pichia pastoris ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The Pichia pastoris TRP1 and HIS3 genes were cloned by complementation of the Saccharomyces cerevisiae trp1 and his3 mutants, respectively, and their nucleotide sequence was determined. The P. pastoris TRP1 gene includes an open reading frame (ORF) of 714 nucleotides corresponding to a polypeptide of 237 amino acids whose sequence shares about 40% identity with that of TRP1 encoding proteins in other yeast species. DNA sequencing showed that an ORF of 858 nucleotides, encoding a protein of 285 amino acids with high homology to inorganic pyrophosphatases (IPP1), is located downstream of the P. pastoris TRP1 gene. Both genes converge in this chromosomal region, showing a genetic organization analogous to that found in the Kluyveromyces lactis genome. The P. pastoris HIS3 gene possesses an ORF of 675 nucleotides, encoding a polypeptide of 224 amino acids which shows 74·1% identity to the homologous S. cerevisiae protein. The hexameric consensus GCN4 binding sequence (TGACTC), characteristic of many amino acid biosynthetic genes, is present in the promoter region. The TRP1 and IPP1 sequences were deposited in the EMBL databank under Accession Number AJ001000. The Accession Number of the HIS3 gene is U69170. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; chromosome VII ; ribonuclease PH ; HGH1 ; YGR187c ; YGR189c ; YGR194c ; YGR195w ; YGR196c ; YGR198w ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have deleted six different ORFs of unknown function located on the right arm of Saccharomyces cerevisiae chromosome VII; namely, YGR187c/HGH1, YGR189c, YGR194c, YGR195w, YGR196c and YGR198w. No basic phenotypes could be attributed to the strains deleted in any of genes YGR187c/HGH1, YGR189c, YGR194c and YGR196c. These deletants did not show mating, sporulation or growth defects under any of the conditions tested. However, spores bearing deletions in either the YGR195w or YGR198w genes were unable to develop into macroscopical colonies. The YGR195w gene product shows significant homology with bacterial ribonuclease PH, an enzyme hitherto undescribed in yeasts, and its deletion causes a loss of viability after one to three rounds of cell division. Overexpression of this gene, using a tetracycline-regulatable promoter system, did not cause any effect on the cells. Contrary to what has been reported for prokaryotic homologs, this enzyme could play an essential role in yeast cell biology. The product encoded by the other essential ORF, YGR198w, shows no significant homology with any protein of known function in the databases. Spores bearing the deletion usually germinate and give rise to microcolonies of 50-100 non-viable cells. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 813-825 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We describe the quantitative monitoring of TATA-binding protein (TBP) localization and expression in living Saccharomyces cerevisiae cells. We replaced the endogenous TBP with a green fluorescent protein (GFP) · TBP fusion, which was imaged quantitatively by laser scanning confocal microscopy (LSCM). When GFP · TBP expression was altered by using various promoters, the levels measured by LSCM correlated well with the levels determined by immunoblot of whole cell extract protein. These results show that GFP · TBP imaging not only offers a method of measurement equivalent to a more conventional technique but also provides real-time quantitation in living cells and subcellular localization information. Time-lapse confocal imaging of GFP · TBP in mitotic yeast cells revealed that it remains localized to the nucleus and displays an asymmetric distribution (1:0·7) between mother and daughter cells. Based on this and data from a mutant which underexpresses GFP · TBP, we suggest that intracellular levels of TBP are near rate-limiting for growth and viability. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 963-967 
    ISSN: 0749-503X
    Keywords: gluconeogenesis ; PEPCK ; Kluyveromyces lactis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The KlPCK1 gene encoding phosphoenolpyruvate carboxykinase (PEPCK; ATP-dependent) was cloned from the Kluyveromyces lactis genome using a PCR amplicon from Saccharomyces cerevisiae PCK1 gene as a probe. A DNA fragment of about 4·8 kb containing KlPCK1 complemented PEPCK activity of the mutant of S. cerevisiae defective in PEPCK. The KlPCK1 gene has an open reading frame of 1629 bp (543 amino acids). The KlPCK1 nucleotide sequence and deduced amino acid sequence showed 76% and 84% homologies to those of S. cerevisiae PCK1, respectively. Multiple alignment of ATP-dependent PEPCK genes shows highly conserved regions. The nucleotide sequence of KlPCK1 has been submitted to the DDBJ/GenBank/EMBL data bank with Accession Number U88575. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 14 (1998), S. 905-913 
    ISSN: 0749-503X
    Keywords: carbon dioxide ; cytostasis ; G1 arrest ; meiosis ; sporulation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Limitation of nutrients allows yeast cells to arrest proliferation at G1 phase of the cell cycle and to enter the so-called stationary phase. We show here another pathway for cytostasis, which is associated with extracellular accumulation of bicarbonate and the resulting alkalisation of medium during the proliferation of cells respiring acetate. Alkalisation of medium by addition of bicarbonate or alkaline buffers ceased proliferation at G1 phase of logarithmically growing cells and caused a severe drop in G1-cyclin (CLN1 and CLN2) mRNAs. The arrested cells were heat-shock resistant, suggesting that the cells entered the stationary phase. Cells confluently grown on acetate re-entered into the cell cycle after acidification of the culture medium. These results indicate that external alkalisation is a primary cause of the cytostasis. The alkali-induced G1 arrest was shown to be cyclic AMP (cAMP)-independent using mutant cells which lack a functional Ras/cAMP signaling pathway. Alkalisation of medium also stimulated meiosis and sporulation in rich acetate medium, confirming our previous proposal that environmental alkalisation but not nitrogen limitation is a key condition for entry into meiosis and sporulation. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    ISSN: 0749-503X
    Keywords: S. pastorianus ; S. cerevisiae ; S. bayanus ; chromosome co-existence ; chromosomal rearrangement ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The bottom fermenting yeasts in our collection were classified as Saccharomyces pastorianus on the basis of their DNA relatedness. The genomic organization of bottom fermenting yeast was analysed by Southern hybridization using eleven genes on chromosome IV, six genes on chromosome II and five genes on chromosome XV of S. cerevisiae as probes. Gene probes constructed from S. cerevisiae chromosomes II and IV hybridized strongly to the 820-kb chromosome and the 1500-kb chromosome of the bottom fermenting yeast, respectively. Five gene probes constructed from segments of chromosome XV hybridized strongly to the 1050-kb and the 1000-kb chromosomes. These chromosomes are thought to be S. cerevisiae-type chromosomes. In addition, these probes also hybridized weakly to the 1100-kb, 1350-kb, 850-kb and 700-kb chromosome. Gene probes constructed from segments including the left arm to TRP1 of chromosome IV and the right arm of chromosome II hybridized to the 1100-kb chromosome of S. pastorianus. Gene probes constructed using the right arm of chromosome IV and the left arm of chromosome II hybridized to the 1350-kb chromosome of S. pastorianus. These results suggested that the 1100-kb and 1350-kb chromosomes were generated by reciprocal translocation between chromosome II and IV in S. pastorianus. Three gene probes constructed using the right arm of chromosome XV hybridized weakly to the 850-kb chromosome, and two gene probes from the left arm hybridized weakly to the 700-kb chromosome. These results suggested that chromosome XV of S. cerevisiae was rearranged into the 850-kb and 700-kb chromosomes in S. pastorianus. These weak hybridization patterns were identical to those obtained with S. bayanus. Therefore, two types of chromosome co-exist independently in bottom fermenting yeast: one set which originated from S. bayanus and another set from S. cerevisiae. This result supports the hypothesis that S. pastorianus is a hybrid of S. cerevisiae and S. bayanus. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...