GENETIC DETERMINATION OF POLYGALACTURONASE PRODUCTION IN WILD-TYPE AND LABORATORY STRAINS OF SACCHAROMYCES-CEREVISIAE

The genetic determination of polygalacturonase (PG) production in Sacc haromyces cerevisiae was studied by biochemical and classical genetic techniques. Crosses of PG(+) strains with PG(-) strains showed that in the haploid wild-type-derived strain, two structural genes were invol ved in the production of a hydrolysis halo on plates with polygalactur onic acid. However, in the case of PG(+) laboratory strain IM1-8b, the phenotype was controlled by only one structural of PG(-) LM1-8b mutan ts demonstrated the existence of at least two complementation groups. All these genetic results were assessed biochemically by means of cati on-exchange chromatography. Two enzymes were separated in the wild-typ e strain, and only one in the laboratory strain. The three enzymes had different K-m values, molecular masses, and optimal pHs for activity.