[Isolation and certain features of a polyphosphate phosphohydrolase deficient mutant of the fungus Neurospora crassa].

A polyphosphatase deficient mutant of Neurospora crassa has been isolated. The criterion for selecting the mutant was the capacity of the fungus to assimilate polyphosphates as the source of exogenous phosphorus. The mutant like the parent strain ad-6, was an adenine auxotroph but differed from the parent strain by a lower growth rate though, at the stationary stage, its biomass reached the same level as in the strain ad-6. The character of changes in the activity of polyphosphatase in the course of growth was the same in the two cultures, but the activity of the enzyme in the mutant was considerably lower at all the growth stages. The content of polyphosphate fractions with the highest molecular weight increased twofold in the mutant culture. These data suggest that there is a close metabolic and topographic correlation between polyphosphatase and the highest molecular weight fractions of polyphosphates in N. crassa.