Interaction of super-repressible and dominant constitutive mutations for the synthesis of galactose pathway enzymes in Saccharomyces cerevisiae.
Two dominant uninducible mutant alleles in the gal80 locus were identified. The GAL80s-1 and GAL80s-2 mutants showed novel phenotypes in response to the newly isolated GAL81-1 mutant allele, a dominant constitutive mutation linked to the gal4 locus; the GAL80s-1 GAL81-1 strain was inducible and the GAL80s-2 GAL81-1 strain was uninducible. Many galactose positive revertants from the GAL80s-2 GAL81-1 strain were isolated. It was proved that each revertant was due to a secondary mutation either in the gal80 or GAL81 locus, whereas revertants due to mutation at the supposed controlling site for the structural gene cluster of the galactose-pathway enzymes have not been isolated.
D002262:Carboxy-Lyases / Q000378:metabolism; D005690:Galactose / Q000378:metabolism*; D005796:Genes; D005799:Genes, Dominant; D005809:Genes, Regulator; D005838:Genotype; D009154:Mutation; D010641:Phenotype; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
D002262:Carboxy-Lyases; D005690:Galactose