Carbon catabolite repression of invertase during batch cultivations of Saccharomyces cerevisiae : the role of glucose, fructose, and mannose

1998 ◽  
Vol 50 (5) ◽  
pp. 579-582 ◽  
Author(s):  
J. Dynesen ◽  
H. P. Smits ◽  
L. Olsson ◽  
J. Nielsen
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Catabolite Repression ◽  
Carbon Catabolite Repression

scholarly journals Carbon catabolite repression in pectin digestion by phytopathogen Dickeya dadantii

2021 ◽  
Author(s):  
Shiny Martis B ◽  
Michel Droux ◽  
William Nasser ◽  
Sylvie Reverchon ◽  
Sam Meyer
Keyword(s):  
Catabolite Repression ◽  
Carbon Catabolite Repression ◽  
Degradation Pathway ◽  
Hplc Method ◽  
Metabolic Switch ◽  
Dickeya Dadantii ◽  
Transcriptional Regulatory ◽  
Genes Encoding ◽  
Regulatory Model

The catabolism of pectin from the plant cell walls plays a crucial role in the virulence of the phytopathogen Dickeya dadantii. In particular, the timely expression of pel genes encoding major pectate lyases is essential to circumvent the plant defense systems and induce a massive pectinolytic activity during the maceration phase. While previous studies identified the role of a positive feedback loop specific to the pectin degradation pathway, here we show that the pel> expression pattern is controlled by a metabolic switch between glucose and pectin. We develop a dynamical and quantitative regulatory model of this process integrating the two main regulators CRP and KdgR related to these two sources of carbon, and reproducing the concentration profiles of the associated metabolites, cAMP and KDG respectively, quantified using a new HPLC method. The model involves only 5 adjustable parameters, and recapitulates the dynamics of these metabolic pathways during bacterial growth together with the regulatory events occurring at the promoters of two major pel genes, pelE and pelD. It highlights their activity as an instance of carbon catabolite repression occurring at the transcriptional regulatory level, and directly related to the virulence of D. dadantii. The model also shows that quantitative differences in the binding properties of common regulators at these two promoters resulted in a qualitative different role of pelD and pelE in the metabolic switch, and also likely in conditions of infection, explaining their evolutionary conservation as separate genes in this species.

Disruption of regulatory gene GAL80 in Saccharomyces cerevisiae: effects on carbon-controlled regulation of the galactose/melibiose pathway genes

1984 ◽  
Vol 4 (8) ◽  
pp. 1521-1527
Author(s):  
T E Torchia ◽  
R W Hamilton ◽  
C L Cano ◽  
J E Hopper
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Catabolite Repression ◽  
Carbon Catabolite Repression ◽  
Regulatory Gene ◽  
Negative Regulator ◽  
Null Mutation ◽  
Null Mutant ◽  
Wild Type

In Saccharomyces cerevisiae, the transcriptional expression of the galactose-melibiose catabolic pathway genes is under the control of at least three regulatory genes, GAL4, GAL80, and GAL3. We have isolated the GAL80 gene and have studied the effect of a null mutation on the carbon-controlled regulation of the MEL1 and GAL cluster genes. The null mutation was achieved in vivo by replacing the chromosomal wild-type GAL80 allele with an in vitro-created GAL80 deletion-disruption mutation. Enzyme activities and RNA levels for the GAL cluster and MEL1 genes were constitutively expressed in the null mutant strain grown on glycerol-lactate and were higher than in the isogenic wild-type yeast strain when compared after growth on galactose. Carbon catabolite repression of the GAL cluster and MEL1 genes, which occurs at the level of transcription, is retained in the null mutant. Deletion of the GAL80 gene in a gal4 cell does not restore GAL cluster and MEL1 gene expression. The data demonstrate that (i) the GAL80 protein is a purely negative regulator, (ii) the GAL80 protein does not mediate carbon catabolite repression, and (iii) the GAL4 protein is not simply an antagonizer of GAL80-mediated repression.

scholarly journals Disruption of regulatory gene GAL80 in Saccharomyces cerevisiae: effects on carbon-controlled regulation of the galactose/melibiose pathway genes.

1984 ◽  
Vol 4 (8) ◽  
pp. 1521-1527 ◽  
Author(s):  
T E Torchia ◽  
R W Hamilton ◽  
C L Cano ◽  
J E Hopper
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Catabolite Repression ◽  
Carbon Catabolite Repression ◽  
Regulatory Gene ◽  
Negative Regulator ◽  
Null Mutation ◽  
Null Mutant ◽  
Wild Type

In Saccharomyces cerevisiae, the transcriptional expression of the galactose-melibiose catabolic pathway genes is under the control of at least three regulatory genes, GAL4, GAL80, and GAL3. We have isolated the GAL80 gene and have studied the effect of a null mutation on the carbon-controlled regulation of the MEL1 and GAL cluster genes. The null mutation was achieved in vivo by replacing the chromosomal wild-type GAL80 allele with an in vitro-created GAL80 deletion-disruption mutation. Enzyme activities and RNA levels for the GAL cluster and MEL1 genes were constitutively expressed in the null mutant strain grown on glycerol-lactate and were higher than in the isogenic wild-type yeast strain when compared after growth on galactose. Carbon catabolite repression of the GAL cluster and MEL1 genes, which occurs at the level of transcription, is retained in the null mutant. Deletion of the GAL80 gene in a gal4 cell does not restore GAL cluster and MEL1 gene expression. The data demonstrate that (i) the GAL80 protein is a purely negative regulator, (ii) the GAL80 protein does not mediate carbon catabolite repression, and (iii) the GAL4 protein is not simply an antagonizer of GAL80-mediated repression.

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