ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
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
  • Genetics  (5)
  • 1990-1994  (5)
  • 1980-1984
  • 1970-1974
  • 1940-1944
  • 1935-1939
  • 1990  (5)
  • 1
    Electronic Resource
    Electronic Resource
    Chimeric genes and transgenic plants are used to study the regulation of genes involved in symbiotic plant-microbe interactions (nodulin genes) (1990)
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 11 (1990), S. 182-196 
    Details
    ISSN: 0192-253X
    Keywords: nodulins ; leghemoglobin ; glutamine synthetase ; Enod2 ; cis-acting elements ; transacting factors ; Agrobacterium turnefaciens ; A. rhizogenes ; binary vectors ; plant transformation ; chimeric genes ; chloramphenicol acetyltransferase ; glucuronidase ; cytokinin induction ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Nodulin genes are plant genes specifically activated during the formation of nitrogen-fixing nodules on leguminous plants. These genes are interesting to study since they are not only induced in a specific developmental fashion by signals coming directly or indirectly from the rhizobial symbiont, but are also expressed in a tissue-specific manner. By examining the expression of chimeric nodulin-reporter genes in transgenic legume plants it has been shown that nodule specific expression is mediated by DNA sequences present in the 5′upstream region of several nodulin genes. Here we summarize the available data on these cis-acting elements and the trans-acting factors interacting with them. We also review experiments designed to identify rhizobial “signals” which may play a role in nodule specific gene expression.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/dvg.1020110304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Metabolic regulation in the yeast Hansenula polymorpha. Growth of dihydroxyacetone kinase/glycerol kinase-negative mutants on mixtures of methanol and xylose in continuous cultures (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 6 (1990), S. 107-115 
    Details
    ISSN: 0749-503X
    Keywords: Hansenula polymorpha ; methanol ; glycerol ; dihydroxyacetone ; xylose ; alcohol oxidase ; continuous culture ; regulation ; mutants ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The physiological responses of Hansenula polymorpha wild-type and mutant strains 17B (dihydroxyacetone kinase-negative) and 17BG51 (dihydroxyacetone kinase- and glycerol kinase-negative) to growth on mixtures of xylose and methanol in chemostats were investigated. Increasing methanol concentrations (0-110 mM) in the feed of the wild-type culture resulted in increasing cell densities and a gradual switch towards methanol metabolism. At the lower methanol feed concentrations the mutant cultures used methanol and xylose to completion and changes in enzyme patterns comparable to the wild type were observed. This was not reflected in significant changes in cell densities. Instead, formaldehyde assimilation resulted in dihydroxyacetone (DHA) production, which was proportional to the amount of methanol added. At intermediate methanol concentration the cultures showed a strong variation in DHA levels and cell densities. Further increased in the methanol feed concentrations resulted in a drop in DHA accumulation rates, repression of alcohol oxidase synthesis and accumulation of residual methanol. The phenomena were studied in more detail in transition experiments and with gradients of methanol. The results indicate that xylulose-5-phosphate (Xu5P) generated in xylose metabolism served as acceptor molecule for formaldehyde assimilation by the peroxisomal enzyme DHA synthase. Accumulation of DHA in the mutant cultures, however, further diminished the availability of carbon for growth. The data suggest that with increasing methanol concentrations Xu5P eventually became growth rate limiting. This resulted in an unstable situation but wash-out of the culture did not occur to a significant extent. Instead, DHA accumulation ceased and cell densities, and enzymes specifically involved in xylose metabolism increase, indicating that the organism resumed its xylose metabolism. The molecular mechanisms controlling the partitioning of Xu5P over xylose (pentose phosphate pathway) and methanol (peroxisome) metabolism under these conditions remain to be elucidated.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320060204
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Classical transketolase functions as the formaldehyde-assimilating enzyme during growth of a dihydroxyacetone synthase-negative mutant of the methylotrophic yeast Hansenula polymorpha on mixtures of xylose and methanol in continuous cultures (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 6 (1990), S. 117-125 
    Details
    ISSN: 0749-503X
    Keywords: Hansenula polymorpha ; methanol ; dihydroxyacetone ; xylose ; mutants ; transketolase ; formaldehyde ; continuous culture ; peroxisome ; regulation ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Contrary to expectation, a mutant of Hansenula polymorpha blocked in dihydroxyacetone (DHA) synthase was able to assimilate methanol-carbon when grown in chemostat culture on mixtures of xylose and methanol. Incubation of a DHA synthase- and DHA kinase-negative double mutant resulted in DHA accumulation, indicating that a DHA synthase-type of reaction was involved. Low residual DHA synthase activity subsequently was shown to be present when using an assay with improved sensitivity. This activity was not associated with the (mutated) DHA synthase protein, which was still present in the peroxisomes, but with the enzyme transketolase. Transketolase from methanol grown cells was purified (525-fold) to homogeneity in 9% yield. The native enzyme was dimeric, as has been reported fro other transketolases, with a subunit molecular weight of 74000. The affinity of the purified enzyme for formaldehyde was low (Km = 5 mM), but high for xylulose-5-phosphate (ca. 10 μM). The in vivo functioning of transketolase in formaldehyde assimilation, and the influence of the hydration state of formaldehyde is discussed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320060205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    The glucanase-soluble mannoproteins limit cell wall porosity in Saccharomyces cerevisiae (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 6 (1990), S. 491-499 
    Details
    ISSN: 0749-503X
    Keywords: Cell wall porosity ; permeability ; mannan ; cell wall composition ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The cell porosity of batch-grown Saccharomyces cerevisiae was maximal in the early exponential phase and fell off rapidly to lower levels in later growth phases.Treatment of stationary-phase cells with alpha-mannosidase restored wall porosity to the level of cells in early exponential phase. When cells in the early exponential phase were treated with alpha-mannosidase, or tunicamycin, an inhibitor of N-glycosylation, even higher porosities were obtained. Mutants with truncated mannan side-chains in their wall proteins also had very porous walls. The importance of the mannan side-chains for wall porosity was also seen during sexual induction. Treatment with alpha pheromone, which leads to the formation of wall proteins with shorter mannan side-chains, enhanced wall porosity.Disulphide bridges also affect cell wall porosity. They were predominantly found in the glucanase-soluble wall proteins. Because the main part of the mannan side-chains is also found in this family of wall proteins, our results demonstrate that the glucanase-soluble mannoproteins limit cell wall porosity in yeast.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320060606
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    An assay of relative cell wall porosity in Saccharomyces cerevisiae, Kluyveromyces lactis and Schizosaccharomyces pombe (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 6 (1990), S. 483-490 
    Details
    ISSN: 0749-503X
    Keywords: Cell wall porosity ; permeability ; polycation assay ; cell wall structure ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have developed a new assay to determine relative cell wall porosity in yeasts, which is based on polycation-induced leakage of UV-absorbing compounds. Polycations with a small hydrodynamic radius as measured by gel filtration (poly-L-lysine) caused cell leakage independent of cell wall porosity whereas polycations with a large hydrodynamic radius (DEAE-dextrans) caused only limited cell leakage due to limited passage through the cell wall. This allowed the ratio between DEAE-dextran- and poly-L-lysine-induced cell leakage to be used as a measure of cell wall porosity in Saccharomyces cerevisiae, Kluyveromyces lactis and Schizosaccharomyces pombe. Using this assay, we found that the composition of the growth medium affected cell wall porosity in S. cerevisiae. In addition, we could show that cell wall porosity is limited by the number of disulphide bridges in the wall and is dependent on cell turgor. It is argued that earlier methods to estimate cell wall porosity in S. cerevisiae resulted in large underestimations.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320060605
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...