Isolation and characterization of yeast strains carrying mutations in the glyceraldehyde-3-phosphate dehydrogenase genes.

Mutant yeast strains were constructed which carry insertion mutations in each of the glyceraldehyde-3-phosphate dehydrogenase structural genes which have been designated TDH1, TDH2, and TDH3. Haploid strains carrying mutations in TDH1 and TDH2 as well as TDH1 and TDH3 were isolated from crosses between strains carrying the appropriate single mutations. The three single mutants as well as the two double mutants grow at wild type rates when ethanol is used as carbon source. Mutant strains lacking only a functional TDH2 allele or a TDH3 allele grow at 50 and 75% of the rate observed for wild type cells, respectively, when glucose is used as carbon source. No growth phenotype was observed for strains lacking only a functional TDH1 allele when either fermentable or nonfermentable carbon sources were used. Evidence is presented that strains lacking functional TDH2 and TDH3 alleles are not viable. These data demonstrate that the presence of a functional TDH2 or TDH3 allele is required for cell growth.