Studies on an interesting Saccharomyces carlsbergensis mutant.

Abstract

A single spore culture, obtained from a local Baker's yeast strain belonging toSaccharomyces carlsbergensis, proved to be a double mutant for an aminoacid and a pyrimidine. It required lysine as well as uracil or cytosine for growth. It failed to utilise thymine and 5-methyl cytosine. It thus possesses the capacity of amination and deamination of pyrimidines and of coupling uracil and cytosine with ribose, but lacks the ability to demethylate pyrimidines.