COMPLEMENTATION OF SACCHAROMYCES-CEREVISIAE ACID-PHOSPHATASE MUTATION BY A GENOMIC SEQUENCE FROM THE YEAST YARROWIA-LIPOLYTICA IDENTIFIES A NEW PHOSPHATASE

A Yarrowia lipolytica gene library was constructed in vector YRp7 and transformed into a Saccharomyces cerevisiae strain lacking both major acid phosphatase activities. A 2.18 kb genomic sequence restoring the ability to hydrolyze alpha-naphthyl phosphate was isolated. Its sequencing revealed an ORF encoding 358 amino acids without significant homology with any known phosphatase. A putative signal peptide and several possible sites for N-glycosylation were identified. Phosphate-regulated expression of the cloned gene was observed in Y. lipolytica. Disruption data favoured the hypothesis that it might encode a minor phosphatase species.