Allelic Complementation at the Adenylosuccinase Locus in Schizosaccharomyces Pombe.

OMPLEMENTATION between allelic mutants at the ad-4 (adenine-4) locus, deficient for the enzyme adenylosuccinase (adenylosuccinate AMP-lyase, C.E. 4322). was first reported in Neurospora (GILES, PARTRIDGE and NELSON 1957; WOODWARD, PARTRIDGE and GILES 1958). It was found that certain pairs of these mutants, which as a result of the absence of adenylosuccinase activity require adenine for growth, can form heterocaryons which are independent of adenine and have restored activity for the enzyme. This report concerns the genetics and complementation pattern of analogous mutants at the ad-8 locus (LEUPOLD 1955) of the yeast Schizosaccharomyces pombe strain Liquefaciens. Some results of this study have been briefly described previously ( MEGNET 1959a; GILES 1964).