Isolation of genes coding for Ade2 and Ura3 homologues from the multinuclear yeast Dipodascus magnusii

Abstract.

Dipodascus magnusii is a nonconventional yeast species with giant multinuclear cells. We constructed two genomic DNA libraries in plasmid vectors and isolated the first two D. magnusii protein-encoding genes, DmADE2 and DmURA3, coding for phosphoribosylaminoimidazole carboxylase and orotidine-5′-phosphate decarboxylase, respectively. Both genes represent functional orthologues, since they complement ade2 and ura3 mutations in Saccharomyces cerevisiae and their putative products possess conserved sequences important for enzymatic activities. Moreover, the results of Southern blot analysis indicate that the genome of D. magnusii contains additional, paralogous sequences of the DmADE2 and DmURA3 genes.