Library

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
  • 1
    Electronic Resource
    Electronic Resource
    The molecular genetics of hexose transport in yeasts (1997)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology reviews 21 (1997), S. 0 
    Details
    ISSN: 1574-6976
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Transport across the plasma membrane is the first, obligatory step of hexose utilization. In yeast cells the uptake of hexoses is mediated by a large family of related transporter proteins. In baker's yeast Saccharomyces cerevisiae the genes of 20 different hexose transporter-related proteins have been identified. Six of these transmembrane proteins mediate the metabolically relevant uptake of glucose, fructose and mannose for growth, two others catalyze the transport of only small amounts of these sugars, one protein is a galactose transporter but also able to transport glucose, two transporters act as glucose sensors, two others are involved in the pleiotropic drug resistance process, and the functions of the remaining hexose transporter-related proteins are not yet known. The catabolic hexose transporters exhibit different affinities for their substrates, and expression of their corresponding genes is controlled by the glucose sensors according to the availability of carbon sources. In contrast, milk yeast Kluyveromyces lactis contains only a few different hexose transporters. Genes of other monosaccharide transporter-related proteins have been found in fission yeast Schizosaccharomyces pombe and in the xylose-fermenting yeast Pichia stipitis. However, the molecular genetics of hexose transport in many other yeasts remains to be established. The further characterization of this multigene family of hexose transporters should help to elucidate the role of transport in yeast sugar metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-6976.1997.tb00346.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Cloning and characterization of three genes (SUT1–3 ) encoding glucose transporters of the yeast Pichia stipitis (1999)
    Oxford BSL : Blackwell Science Ltd
    Molecular microbiology 31 (1999), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: We have identified and characterized three genes, SUT1, SUT2 and SUT3, that encode glucose transporters of the yeast Pichia stipitis. When expressed in a Saccharomyces cerevisiae hxt null mutant strain that is unable to take up monosaccharides, all three proteins restored growth on glucose. Sequencing of the genes revealed open reading frames coding for 553 amino acids in the case of SUT1, and for 550 amino acids in the case of SUT2 and of SUT3. The derived protein sequences are closely related to one another, and show distinct sequence similarities to the S. cerevisiae hexose transporter family and to monosaccharide transporters of other organisms. The Sut2 and Sut3 proteins are nearly identical and differ only in one amino acid. Determination of substrate specificities and kinetic parameters of the individual Sut proteins expressed in a S. cerevisiae hxt1–7 mutant revealed Sut1, Sut2 and Sut3 as glucose transporters with Km values in the millimolar range. The proteins were also able to transport xylose and other monosaccharides, but with a considerably lower affinity. In P. stipitistranscription of SUT1 was strongly induced by glucose and was independent of the oxygen supply. In contrast, SUT2 and SUT3 were only expressed under aerobic conditions, but independent of the carbon source. Cells disrupted for the SUT1 gene did not show any obvious growth phenotype, however low-affinity glucose uptake was lost. Further investigations suggest that the Sut proteins constitute a subfamily of glucose transporters in P. stipitis, and that other and probably unrelated proteins exist additionally mediating high-affinity glucose and xylose uptake.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.1999.01224.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    A multi-layered sensory system controls yeast glycolytic gene expression (1996)
    Oxford BSL : Blackwell Science Ltd
    Molecular microbiology 19 (1996), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.1996.t01-1-442924.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Glucose-induced cAMP signalling in yeast requires both a G-protein coupled receptor system for extracellular glucose detection and a separable hexose kinase-dependent sensing process (2000)
    Oxford, UK : Blackwell Science Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: In Saccharomyces cerevisiae, glucose activation of cAMP synthesis requires both the presence of the G-protein-coupled receptor (GPCR) system, Gpr1-Gpa2, and uptake and phosphorylation of the sugar. In a hxt-null strain that lacks all physiologically important glucose carriers, glucose transport as well as glucose-induced cAMP signalling can be restored by constitutive expression of the galactose permease. Hence, the glucose transporters do not seem to have a regulatory function but are only required for glucose uptake. We established a system in which the GPCR-dependent glucose-sensing process is separated from the glucose phosphorylation process. It is based on the specific transport and hydrolysis of maltose providing intracellular glucose in the absence of glucose transport. Preaddition of a low concentration (0.7 mM) of maltose to derepressed hxt-null cells and subsequent addition of glucose restored the glucose-induced cAMP signalling, although there was no glucose uptake. Addition of a low concentration of maltose itself does not increase the cAMP level but enhances Glu6P and apparently fulfils the intracellular glucose phosphorylation requirement for activation of the cAMP pathway by extracellular glucose. This system enabled us to analyse the affinity and specificity of the GPCR system for fermentable sugars. Gpr1 displayed a very low affinity for glucose (apparent Ka = 75 mM) and responded specifically to extracellular α and βd-glucose and sucrose, but not to fructose, mannose or any glucose analogues tested. The presence of the constitutively active Gpa2val132 allele in a wild-type strain bypassed the requirement for Gpr1 and increased the low cAMP signal induced by fructose and by low glucose up to the same intensity as the high glucose signal. Therefore, the low cAMP increases observed with fructose and low glucose in wild-type cells result only from the low sensitivity of the Gpr1-Gpa2 system and not from the intracellular sugar kinase-dependent process. In conclusion, we have shown that the two essential requirements for glucose-induced activation of cAMP synthesis can be fulfilled separately: an extracellular glucose detection process dependent on Gpr1 and an intracellular sugar-sensing process requiring the hexose kinases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02125.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Induction of pyruvate decarboxylase in glycolysis mutants of Saccharomyces cerevisiae correlates with the concentrations of three-carbon glycolytic metabolites (1993)
    Springer
    Archives of microbiology 160 (1993), S. 324-328 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Pyruvate decarboxylase ; Pyruvate kinase ; Signalling ; Glycolysis mutants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Pyruvate decarboxylase, PDCase, activity in wild-type yeast cells growing on ethanol is quite low but increases up to tenfold upon addition of glucose, less with galactose and only slightly with glycerol. PDCase levels in glycolysis mutant strains growing on ethanol or acetate were higher than in the wild-type strain. These levels correlated with the sum of the concentrations of three-carbon glycolytic metabolites. The highest accumulation was observed in a fructose bisphosphate aldolase deletion mutant concomintant with the highest PDCase activity wild-type level. On the other hand, the PDCase levels in the different mutants again correlated with the sum of the concentrations of the three-carbon glycolytic metabolites. This was interpreted to mean that full induction of PDCase activity requires the accumulation of hexose-and triosephosphates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00292085
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A rapid and highly efficient method for PCR-based site-directed mutagenesis using only one new primer (1995)
    Springer
    Current genetics 28 (1995), S. 197-198 
    Details
    ISSN: 1432-0983
    Keywords: Site-directed mutagenesis ; Polymerase chain reaction ; High efficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We present a rapid, cheap and highly efficient method for site-directed mutagenesis using the polymerase chain reaction (PCR). This method is applicable to every DNA fragment which has to be cloned into the multiple cloning site of any vector, or vector pair, in two different orientations. It requires only two primers, one new and specific mutagenic primer and one of the usual sequencing primers. In the first PCR, a mutagenic DNA fragment is synthesized which is amplified exponentially in the second PCR. In contrast, wild-type sequences are only linearly amplified resulting in an efficiency of mutagenesis of nearly 100%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00315788
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Saccharomyces cerevisiae phosphoglucose isomerase and fructose bisphosphate aldolase can be replaced functionally by the corresponding enzymes of Escherichia coli and Drosophila melanogaster (1993)
    Springer
    Current genetics 23 (1993), S. 187-191 
    Details
    ISSN: 1432-0983
    Keywords: Phosphoglucose isomerase ; Fructose-1,6-bisphosphate aldolase ; Heterologous gene expression ; Multi-enzyme aggregates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two glycolytic enzymes, phosphoglucose isomerase and fructose-1,6-bisphosphate aldolase, of Saccharomyces cerevisiae could be replaced by their heterologous counterparts from Escherichia coli and Drosophila melanogaster. Both heterologous enzymes, which show respectively little and no sequence homology to the corresponding yeast enzymes, fully restored wild-type properties when their genes were expressed in yeast deletion mutants. This result does not support notions of an obligatory formation of glycolytic multi-enzyme aggregates in yeast; nor does it support possible regulatory functions of yeast phosphoglucose isomerase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00351494
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Unusual regulation of the uptake system for branched-chain amino acids in Corynebacterium glutamicum (1993)
    Springer
    Archives of microbiology 159 (1993), S. 147-152 
    Details
    ISSN: 1432-072X
    Keywords: Branched-chain amino acids ; Uptake-system ; Threonine dehydratase ; Isoleucine efflux ; Corynebacterium glutamicum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The uptake of branched-chain amino acids in threonine-dehydratase deficient mutants of Corynebacterium glutamicum is dependent on the presence of relatively high (〉1 mM) intracellular concentrations of isoleucine, valine or leucine. This indicates that the respective uptake-system is induced by its substrate, i.e. branched-chain amino acids, at the internal side. This unusual regulation presumably is the reason for the failure to obtain mutants deficient in isoleucine uptake by use of a selection scheme which starts from isoleucine auxotroph mutants. The physiological meaning of this regulation is discussed with respect to isoleucine efflux and the cyclic retention hypothesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00250275
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Sequence and function analysis of a 4.3 kb fragment of Saccharomyces cerevisiae chromosome II including three open reading frames (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1257-1257 
    Details
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320100914
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Different signals control the activation of glycolysis in the yeast Saccharomyces cerevisiae (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 9 (1993), S. 761-770 
    Details
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; activation of glycolysis ; signalling ; cyclic AMP ; fructose-2,6-bisphosphate ; phosphofructokinase ; phosphoglucose isomerase ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The glycolytic pathway in Saccharomyces cerevisiae is activated by fermentable sugars at several steps. Mutants with deletions of genes coding for enzymes of the upper part of glycolysis were used to characterize the triggering mechanisms. Synthesis of fructose-2,6-bisphophate is catalysed by two 6-phosphofructo-2-kinase isoenzymes, one of which is activated by fermentable sugars while synthesis of the second enzyme is induced (Kretschmer and Fraenkel, 1991). Increase in the level of fructose-2, 6-bisphosphate is demonstrated to depend on an internal metabolite upstream of the phosphoglucose isomerase reaction. The signalling process correlates with distinct temporal changes in the concentration of glucose-6-phosphate but not with its absolute level, indicating an adaptational mechanism. It is independent of the uptake and phosphorylation systems used by different sugars. Interestingly, this increase, although delayed, could also be observed in strains lacking the rapid cAMP increase after sugar addition which is thought to be responsible for the activating process. Synthesis of glucose-6-P and fructose-6-P is needed for the complete induction of pyruvate kinase and inactivation of fructose-1,6-bisphosphatase. On the other hand, induction of pyruvate decarboxylase depends mainly on a signal in the lower part of glycolysis.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/yea.320090710
    Library Location Call Number Volume/Issue/Year 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...