ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • gene expression  (3)
  • β-cyclodextrin  (3)
  • Chlamydomonas (l-amino-acid oxidase)  (2)
  • Springer  (8)
Collection
Publisher
Years
  • 1
    ISSN: 1432-2048
    Keywords: l-amino-acid oxidase (molecular properties) ; Chlamydomonas (l-amino-acid oxidase) ; Flavoprotein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Anl-amino-acid oxidase (EC 1.4.3.1) that catalyzes the oxidative deamination of twelvel-amino acids has been purified 21-fold and with 14% yield to electrophoretic homogeneity fromChlamydomonas reinhardtii cells by ammonium-sulfate fractionation, gel filtration through Sephacryl and Superose, anion-exchange chromatography and preparative electrophoresis in polyacrylamide gels. The native enzyme is a protein of 470 kDa and consists of eight identical or similarsized subunits of 60 kDa each. Optimum pH and temperature were 8.2 and 55° C, respectively, with a Q10 (45–55° C) of 1.7 and an activation energy of 45 kJ · mol−1. Its absorption spectrum showed, in the visible region, maxima at 360 and 444 nm, characteristic of a flavoprotein with a calculated flavin content of 7.7 mol FAD per mol of native enzyme. ApparentK m values of the twelvel-amino acids which can act as substrates ofl-amino-acid oxidase ranged between 31 μM for phenylalanine and 176 μM for methionine. The effect of several specific group reagents, chelating agents and bivalent cations on enzyme activity has also been studied.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-2048
    Keywords: l-amino-acid oxidase (molecular properties) ; Chlamydomonas (l-amino-acid oxidase) ; Flavoprotein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An l-amino-acid oxidase (EC 1.4.3.1) that catalyzes the oxidative deamination of twelve l-amino acids has been purified 21-fold and with 14% yield to electrophoretic homogeneity from Chlamydomonas reinhardtii cells by ammonium-sulfate fractionation, gel filtration through Sephacryl and Superose, anion-exchange chromatography and preparative electrophoresis in polyacrylamide gels. The native enzyme is a protein of 470 kDa and consists of eight identical or similarsized subunits of 60 kDa each. Optimum pH and temperature were 8.2 and 55° C, respectively, with a Q10 (45–55° C) of 1.7 and an activation energy of 45 kJ · mol−1. Its absorption spectrum showed, in the visible region, maxima at 360 and 444 nm, characteristic of a flavoprotein with a calculated flavin content of 7.7 mol FAD per mol of native enzyme. Apparent K m values of the twelve l-amino acids which can act as substrates of l-amino-acid oxidase ranged between 31 μM for phenylalanine and 176 μM for methionine. The effect of several specific group reagents, chelating agents and bivalent cations on enzyme activity has also been studied.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-5117
    Keywords: Turbellaria ; Dugesia ; homeobox ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To identify potential pattern control and cell determination and/or differentiation genes in the freshwater planarian Dugesial (G.) tigrina, we searched for homeobox genes of different types in the genome of this primitive metazoan. We applied two basic approaches: 1) Screening the cDNA library with degenerate oligonucleotides corresponding to the most conserved amino acid sequence from helix-3 of the homeodomain of each family; and 2) PCR amplification of genomic DNA or cDNA, using two sets of degenerated oligonucleotides corresponding to helices 1 and 3 of the homeodomain or two specific domains of the POU family. Using the first strategy we have identified and characterized two tissue-specific cell determination and/or differentiation NK-type homeobox genes. Using the second strategy we have identified several homeobox genes that belong to the HOM/Hox, paired (prd) or POU families.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    World journal of microbiology and biotechnology 12 (1996), S. 189-202 
    ISSN: 1573-0972
    Keywords: gene expression ; nodule development ; nodulin genes ; Rhizobium-legume symbiosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Rhizobium, Bradyrhizobium and Azorhizobium can elicit the formation of N2-fixing nodules on the roots or stems of their leguminous host plants. The nodule formation involves several developmental steps determined by different sets of genes from both partners, the gene expression being temporally and spatially coordinated. The plant proteins that are specifically synthesised during the formation and function of the nodule are called nodulins. The nodulins that are expressed before the onset of N2 fixation are termed early nodulins. These proteins are probably involved in the infection process as well as in nodule morphogenesis rather than in nodule function. The nodulins expressed just before or during N2 fixation are termed late nodulins and they participate in the function of the nodule by creating the physiological conditions required for nitrogen fixation, ammonium assimilation and transport. In this review we will describe nodulins, nodulin genes and the relationship between nodulin gene expression and nodule development. The study of nodulin gene expression may provide insight into root-nodule development and the mechanism of communication between bacteria and host plant.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1573-1111
    Keywords: β-cyclodextrin ; 2-hydroxypropyl β-CD ; phenothiazine ; photochemically-induced fluorescence spectroscopy ; molecular absorption spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The photo-oxidation reaction of phenothiazine has been studied in the presence ofβ-cyclodextrin (β-CD) and 2-hydroxypropylβ-cyclodextrin (HP β-CD). The influence of these organized media on the formation of the oxidation photoproduct upon UV irradiation has been investigated. Phenothiazine forms an inclusion complex with the cyclodextrins. The stoichiometry and formation constant of the complex formed with 2-hydroxypropyl β-CD have been calculated using the changes of the fluorescence emission signal and of the absorbance of the drug upon inclusion. An increase of the fluorescence intensity of the photogenerated product is attained when it becomes included inside the cyclodextrin cavity.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-1111
    Keywords: Azure A ; β-cyclodextrin ; inclusion complex ; photochemically induced fluorescence spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The photooxidation of Azure A and fluorescence properties of Azure A and its photoproduct have been investigated in aqueous media and in the presence ofβ-cyclodextrin (β-CD). The fluorescence intensity of the complex formed between the photoproduct and β-CD was found to be three times higher than that of the uncomplexed Azure A photoproduct. A complex formation constant of 110±40 M−1 was calculated using the Benesi-Hildebrand treatment of the fluorescence emission data. Although the stoichiometry of the Azure A photoproduct: β-CD complex was found to be 1: 1, it seems that the Azure A structure is only partially included. Calibration graphs were plotted for the free Azure A photoproduct and the photogenerated product included in β-CD. The analytical parameters and quantification limits were determined.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 10 (1991), S. 471-484 
    ISSN: 1573-1111
    Keywords: β-cyclodextrin ; Triton X-100 ; cyclodextrin inclusion ; fluorescence spectroscopy ; nuclear magnetic resonance spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The spectral characteristics of the surfactant, Triton X-100, in the absence and presence ofβ-cyclodextrin have been examined. The fluorescence of Triton X-100 is concentration dependent and is markedly enhanced in the presence ofβ-cyclodextrin. Analysis of the variations in the excitation-emission profiles of the surfactant with concentration suggests excimer emission at concentrations above the critical micelle concentration (CMC). Nuclear magnetic resonance (NMR) spectroscopy suggests that the phenyl group is included inside the CD cavity while a portion of the ethylene oxide chain extends outside the cavity. Benesi-Hildebrand type equations were derived to determine the stoichiometry and to estimate the formation constant of the CD: Sf complex.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1573-5117
    Keywords: Planarian ; Hox ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Seven Hox cluster-related genes (Dthox-A to -G) have been isolated from the freshwater triclad Dugesia (G.) tigrina, their sequence compared to other Hox genes and their expression in intact and regenerating organisms analyzed by whole mount in situ hybridization. Sequence comparison analyses show high similarities of D. tigrina Hox genes to anterior and medial groups of coelomate Hox genes. Expression analyses show very early, synchronous, and overlapping expression of Dthox -A, -E, -G and -F in anterior, posterior and lateral regenerative tissues. At one hour of regeneration all Dthox genes studied showed a neat, clear expression at the wound boundary. Later, as the blastema grows, the expression area expands to more proximal regions covering the blastema and the distal postblastema regions. Blastemas formed by intercalary regeneration also show a synchronous expression of the same Hox genes though the onset of activation is much delayed. The finding that the same set of Hox genes is synchronously activated in anterior, posterior, intercalary and lateral regeneration is in sharp contrast to its well established role in specifying antero-posterior pattern during embryonic development. The implications of these results as regards ancestral versus co-opted roles of Hox genes in development and regeneration are discussed.
    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...