A mutation affecting carbon catabolite repression suppresses growth defects in pyruvate carboxylase mutants from Saccharomyces cerevisiae

FEBS Letters

Gamo, Francisco-Javier¹  Gancedo, Carlos¹  Blázquez, Miguel A.¹ 

[1] Instituto de Investigaciones Biomédicas del C.S.I.C., Unidad de Bioquíma y Genética de Levaduras, C/Arturo Duperier no. 4, E-28029 Madrid, Spain

关键词: Pyruvate carboxylase;    Glyoxylate cycle;    Catabolite repression;    Yeast;   

DOI  :  10.1016/0014-5793(95)01337-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Yeasts with disruptions in the genes PYC1 and PYC2 encoding the isoenzymes of pyruvate carboxylase cannot grow in a glucose-ammonium medium (Stucka et al. (1991) Mol. Gen. Genet. 229, 307–315). We have isolated a dominant mutation, BPC1-1, that allows growth in this medium of yeasts with interrupted PYC1 and PYC2 genes. The BPC1-1 mutation abolishes catabolite repression of a series of genes and allows expression of the enzymes of the glyoxylate cycle during growth in glucose. A functional glyoxylate cyle is necessary for suppression as a disruption of gene ICL1 encoding isocitrate lyase abolished the phenotypic effect of BPC1-1 on growth in glucose-ammonium. Concurrent expression from constitutive promoters of genes ICL1 and MLS1 (encoding malate synthase) also suppressed the growth phenotype of pyc1 pyc2 mutants. The mutation BPC1-1 is either allelic or closely linked to the mutation DGT1-1.

【 授权许可】

Unknown