ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Electronic Resource

Growth and adhesion of Enterococcus faecium L-forms (1994)

Jass, Jana ; Phillips, Lisa E. ; Allan, Eunice J. ; [et al.]

Oxford, UK : Blackwell Publishing Ltd

FEMS microbiology letters 115 (1994), S. 0

add to mindlist on the mindlist

Details

ISSN: 1574-6968

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology

Notes: Abstract Comparisons of growth and surface colonisation of Enterococcus faecium L-forms and their cell-walled forms were undertaken to produce information about their ability to form sessile cells. The growth of L-forms in liquid culture was slower than that of the parent. This was reflected in their longer lag phase and slower specific growth rates: 0.16 h−1 for the L-form and 0.81 h−1 for the parent. Although E. faecium L-forms attached to a silastic rubber surface, the attached population density was 10–100-fold less than that of the parent. Confluent biofilms on the silastic surfaces were not observed for either bacterial form. Comparison of the attachment of E. faecium L-form and parent may provide important information on how bacteria overcome host defence mechanisms and antibiotic treatment.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1574-6968.1994.tb06631.x

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

2

Electronic Resource

Assessment of the role of a terrestrial isopod in the survival of a genetically modified pseudomonad and its detection using the polymerase chain reaction (1994)

Clegg, Christopher D. ; Elsas, Jan D. ; Anderson, Jonathan M. ; [et al.]

Oxford, UK : Blackwell Publishing Ltd

FEMS microbiology ecology 15 (1994), S. 0

add to mindlist on the mindlist

Details

ISSN: 1574-6941

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology

Notes: Abstract The effects of a terrestrial isopod, Porcellio scaber, on the survival of a genetically modified pseudomonad were studied. Pseudomonas fluorescens KTG was inoculated onto ash leaf litter and supplied to populations of P. scaber. Plate counts were lower in fresh faeces than the ash leaf litter for P. fluorescens KTG, and higher counts were detected in the faeces for the total bacterial population. When faeces were aged by incubation for up to 7 days at 15–17°C, plate counts for P. fluorescens KTG increased during the first day to a level similar to those in the corresponding ash leaf litter, and remained relatively constant thereafter. The total bacterial population in the faeces continued to increase steadily over the 7 days, whilst remaining at a constant level in the ash leaf litter during the same period. Counts of bacteria in faecal material showed that P. fluorescens KTG was present for 6 days after the isopods had fed on inoculated litter although transit times of food through the gut were as little as 5 h. The implications for GEMMO dispersal of bacterial retention in the gut is considered. The polymerase chain reaction was utilised in the detection of the inserted DNA. Positive amplification of the inserted DNA sequence of P. fluorescens KTG was achieved in ash leaf litter, fresh faeces, and faeces from animal which were supplied uninoculated litter for one day after feeding on the inoculated litter. However, plate counts were more sensitive than the polymerase chain reaction in detecting P. fluorescens KTG in the faeces. Our findings suggest that when the GEMMO is ingested by the woodlouse it can survive within the guts and faeces. This has implications for risk assessment of genetically modified bacteria in terrestrial environments.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1574-6941.1994.tb00240.x

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

3

Electronic Resource

Biofilm formation by the rapidly growing mycobacterial species Mycobacterium fortuitum (1998)

Hall-Stoodley, Luanne ; Lappin-Scott, Hilary

Oxford, UK : Blackwell Publishing Ltd

FEMS microbiology letters 168 (1998), S. 0

add to mindlist on the mindlist

Details

ISSN: 1574-6968

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology

Notes: Rapidly growing mycobacteria (RGM) are found in soil and diverse aquatic environments. Two species, Mycobacterium fortuitum and Mycobacterium chelonae, are associated with disease and are difficult to eradicate. Biofilm formation may be a contributing factor to their mode of transmission and their resistance to antimicrobial agents. We investigated the ability of the RGM species M. fortuitum to colonise surfaces using a modified Robbins device. M. fortuitum formed dense biofilms within 48 h. The high numbers of sessile organisms recovered and the swiftness of colonisation suggest that M. fortuitum readily forms biofilms. These results suggest a novel mechanism for mycobacteria in evading antimicrobial treatment and also indicate that biofilms should be considered possible sites for mycobacterial contamination.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1574-6968.1998.tb13258.x

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

4

Electronic Resource

Enrichment and characterisation of sulfate-reducing bacteria from sandstone rock cores from the UK Continental shelf (1997)

Phillips, Lisa E ; Lappin-Scott, Hilary M

Oxford, UK : Blackwell Publishing Ltd

FEMS microbiology reviews 20 (1997), S. 0

add to mindlist on the mindlist

Details

ISSN: 1574-6976

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology

Notes: A fresh sandstone core was extracted during drilling of an exploration well within a United Kingdom Continental Shelf oilfield at a depth of approximately 1000 m. Scanning electron microscopy of the rock core revealed cell-like structures attached to the sandstone grains. Microbiological analysis demonstrated that the inner core was not sterile but contained sulfate-reducing bacteria and other anaerobes. One enrichment culture of sulfate-reducing bacteria (denoted EX306), was chosen for further study. Enrichments of EX306 showed that it was comprised of a tightly knit group of three different bacteria which continued as a stable community despite repeated subculturing for over 2 years. EX306 was able to utilise pyruvate-producing acetate and propionate as metabolites, growth was optimal at 55°C.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1574-6976.1997.tb00326.x

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

5

Electronic Resource

Effects of biocide treatment and backflow pressure on the permeability of microbially fouled model cores (1988)

Cusack, Francene ; Lappin-Scott, Hilary M. ; Costerton, J. William

Springer

Journal of industrial microbiology and biotechnology 2 (1988), S. 329-335

add to mindlist on the mindlist

Details

ISSN: 1476-5535

Keywords: Oil recovery ; Enthanced oil recovery ; Water flooding ; Isothiazolone

Source: Springer Online Journal Archives 1860-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: Summary Sintered glass bead cores were plugged until the permeability was reduced to 1% or less of the original permeability by the injection of a slime-producing bacterium isolated from produced water. Scanning electron microscopy of fractured core sections showed that the bacteria were predominantly located in the uppermost sections, around the core inlet. Killing the bacterial cells in the plugging biofilm, using a biocide, had little effect on core permeability. The dead cells were only removed when backflow pressure, simulated by inversion of the test core followed by fluid injection, was applied and maintained at 55–69 kPa. Backflow of plugged cores containing live bacteria produced transient pressure-dependent increases in permeability that were proportional to the backflow pressure applied. We conclude that only sustained backflow procedures reduced permeability: such operations are not effective for oil recovery in field conditions.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF01569571

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

6

Electronic Resource

Biodegradation of the chlorophenoxy herbicide (R)-(+)-mecoprop by Alcaligenes denitrificans (1997)

Tett, Vanessa A. ; Willetts, Andrew J. ; Lappin-Scott, Hilary M.

Springer

Biodegradation 8 (1997), S. 43-52

add to mindlist on the mindlist

Details

ISSN: 1572-9729

Keywords: Alcaligenes denitrificans ; biodegradation ; chloroaromatic ; mecoprop (R)-(+)-2(2-methyl-4-chlorophenoxy)propionic acid

Source: Springer Online Journal Archives 1860-2000

Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Notes: Abstract An Alcaligenes denitrificans strain capable of utilizing theherbicide (R)-(+)-2(2-methyl-4-chlorophenoxy)propionicacid (mecoprop) as a sole carbon source was isolated fromsoil and cultured in liquid medium. Crude cell extracts of thebacterium were utilized in spectrophotometric assays toelucidate a biochemical pathway for degradation ofmecoprop. Results indicated a reaction sequence analogousto the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D).GC-MS analysis provided direct evidence for thebiotransformation of mecoprop to the transient metabolite4-chloro-2-methylphenol (MCP). No NADPH-dependentactivity was observed during this reaction. Pyruvate wasverified as the second product derived from the aliphatic sidechain of mecoprop. MCP was subsequently transformed to asubstituted catechol by an NADPH-dependentmonooxygenase. When grown on mecoprop, A.denitrificans was adapted to oxidize catechol and its 4- and3-methylated derivatives indicating the broad substratespecificity of catechol dioxygenase. The microorganism wasdemonstrated to adopt the ortho mechanism of aromaticcleavage which resulted in the formation of2-methyl-4-carboxymethylene but-2-en-4-olide, a reactionintermediate of the β-ketoadipate pathway.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1023/A:1008262901202

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

7

Electronic Resource

Relationship between mass transfer coefficient and liquid flow velocity in heterogenous biofilms using microelectrodes and confocal microscopy (1997)

Stoodley, Paul ; Yang, Shunong ; Lappin-Scott, Hilary ; [et al.]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 56 (1997), S. 681-688

add to mindlist on the mindlist

Details

ISSN: 0006-3592

Keywords: biofilm ; confocal scanning laser microscopy ; laminar flow ; liquid flow velocity ; mass transfer coefficient ; microelectrodes ; Reynolds number ; Sherwood number ; Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: The relationship between local mass transfer coefficient and fluid velocity in heterogenous biofilms was investigated by combining microelectrodes and confocal scanning laser microscopy (CSLM). The biofilms were grown for up to 7 days and consisted of cell clusters separated by interstitial channels. Mass transfer coefficient depth profiles were measured at specific locations in the cell clusters and channels at average flow velocities of 2.3 and 4.0 cm/s. Liquid flow velocity profiles were measured in the same locations using a particle tracking technique. The velocity profiles showed that flow in the open channel was laminar. There was no flow at the top surface of the biofilm cell clusters but the mass transfer coefficient was 0.01 cm/s. At the same depth in a biofilm channel, the flow velocity was 0.3 cm/s and the mass transfer coefficient was 0.017 cm/s. The mass transfer coefficient profiles in the channels were not influenced by the surrounding cell clusters. Local flow velocities were correlated with local mass transfer coefficients using a semi-theoretical mass transfer equation. The relationship between the Sherwood number (Sh,) the Reynolds number (Re,) and the Schmidt number (Sc) was found using the experimental data to find the dimensionless empirical constants (n1, n2, and m) in the equation Sh = n1 + n2Rem Sc1/3. The values of the constants ranged from 1.45 to 2.0 for n1, 0.22 to 0.28 for n2, and 0.21 to 0.60 for m. These values were similar to literature values for mass transfer in porous media. The Sherwood number for the entire flow cell was 10 when the bulk flow velocity was 2.3 cm/s and 11 when the bulk flow velocity was 4.0 cm/s. © 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 56: 681-688, 1997.

Additional Material: 6 Ill.

Type of Medium: Electronic Resource

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

8

Electronic Resource

Oscillation characteristics of biofilm streamers in turbulent flowing water as related to drag and pressure drop (1998)

Stoodley, Paul ; Lewandowski, Zbigniew ; Boyle, John D. ; [et al.]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 57 (1998), S. 536-544

add to mindlist on the mindlist

Details

ISSN: 0006-3592

Keywords: biofilm ; streamers ; biofouling ; drag ; fast Fourier transform analysis ; hydrodynamics ; oscillations ; pressure drop ; Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: Mixed population biofilms consisting of Pseudomonas aeruginosa, P. fluorescens, and Klebsiella pneumoniae were grown in a flow cell under turbulent conditions with a water flow velocity of 18 cm/s (Reynolds number, Re, =1192). After 7 days the biofilms were patchy and consisted of cell clusters and streamers (filamentous structures attached to the downstream edge of the clusters) separated by interstitial channels. The cell clusters ranged in size from 25 to 750 μm in diameter. The largest clusters were approximately 85 μm thick. The streamers, which were up to 3 mm long, oscillated laterally in the flow. The motion of the streamers was recorded at various flow velocities up to 50.5 cm/s (Re 3351) using confocal scanning laser microscopy. The resulting time traces were evaluated by image analysis and fast Fourier transform analysis (FFT). The amplitude of the motion increased with flow velocity in a sigmoidal shaped curve, reaching a plateau at an average fluid flow velocity of approximately 25 cm/s (Re 1656). The motion of the streamers was possibly limited by the flexibility of the biofilm material. FFT indicated that the frequency of oscillation was directly proportional to the average flow velocity (u(ave)) below 9.5 cm/s (Re 629). At u(ave) greater than 9.5 cm/s, oscillation frequencies were above our measurable frequency range (0.12-6.7 Hz). The oscillation frequency was related to the flow velocity by the Strouhal relationship, suggesting that the oscillations were possibly caused by vortex shedding from the upstream biofilm clusters. A loss coefficient (k) was used to assess the influence of biofilm accumulation on pressure drop. The k across the flow cell colonized with biofilm was 2.2 times greater than the k across a clean flow cell. ©1998 John Wiley & Sons, Inc. Biotechnol Bioeng 57: 536-544, 1998.

Additional Material: 7 Ill.

Type of Medium: Electronic Resource

Permalink