Catabolite repression mutants of yeast¹

Abstract

The mechanism of catabolite repression in yeast is not well understood, although it has been established that cAMP does not play a role similar to that found in Escherichia coli. To identify the elements implicated in catabolite repression in yeast, a variety of mutants affected in this process have been isolated by different research groups. A systematic review of the results reported in the literature is presented. The conclusion that can be drawn is that the mechanism of catabolite repression is a complex one, with no single gene controlling all the genes subject to repression. The expression of a given gene or set of genes is controlled by several regulatory genes, but it is not yet known whether these genes act cooperatively or sequentially.

Glucose repression in the yeast Saccharomyces cerevisiae

“…1985). Most of the mutations controlling glucose repression of the SUC genes also affect regulation of the MAL genes (Gancedo and Gancedo, 1986).…”

“…The regulatory pathway appears to be composed of multiple steps and branches regulating subsets of gtucose-repressible genes. Since the last general reviews of the subject (Carlson, 1987;Entian, 1986;Gancedo and Gancedo, 1986), considerable progress has been made, but many crucial elements of the pathway are still not understood.…”

Differential fructose effect in Pachysolen tannophilus and Pichia stipitis

“…In this report, we describe the exertion of catabolite repression [8,9] by D-fructose in P. tannophilus but not in P. stipitis. In this report, we describe the exertion of catabolite repression [8,9] by D-fructose in P. tannophilus but not in P. stipitis.…”

“…When D-fructose was supplied as the sole carbon source, P. tannophilus consumed the sugar and fermented it to ethanol rapidly (data not shown). However, D-xylose repressed the utilization of D-fructose in a manner which is similar to the glucose effect [8,9,17]. Therefore, D-xylose did not affect Dfructose utilization.…”

“…The glucose effect or catabolite repression is typically exerted by D-glucose or metabolically closely related carbon sources including D-fructose [8,9,17]. The ability of D-fructose to exert the glucose effect in P. tannophilus but not in P. stipitis suggests that important differences in the regulation of D-fructose metabolism may exist between the two yeasts.…”