L-proline accumulation and freeze tolerance of Saccharomyces cerevisiae are caused by a mutation in the PRO1 gene encoding gamma-glutamyl kinase.

ABSTRACT: We previously isolated a mutant which showed a high tolerance to freezing that correlated with higher levels of intracellular L-proline derived from L-proline analogue-resistant mutants. The mutation responsible for the analogue resistance and L-proline accumulation was a single nuclear dominant mutation. By introducing the mutant-derived genomic library into a non-L-proline-utilizing strain, the mutant was found to carry an allele of the wild-type PRO1 gene encoding gamma-glutamyl kinase, which resulted in a single amino acid replacement; Asp (GAC) at position 154 was replaced by Asn (AAC). Interestingly, the allele of PRO1 was shown to enhance the activities of gamma-glutamyl kinase and gamma-glutamyl phosphate reductase, both of which catalyze the first two steps of L-proline synthesis

SUBMITTER: Morita Y 

PROVIDER: S-EPMC152471 | biostudies-literature | 2003 Jan

REPOSITORIES: biostudies-literature