The use of genetic engineering to obtain efficient production of porcine pancreatic phospholipase A2 by Saccharomyces cerevisiae

We have developed an efficient production system for porcine pancreatic phospholipase A 2 in Saccharomyces cerevisiae (baker's yeast). The cDNA encoding the prophospholipase A 2 was expressed under the control of the galactose inducible GAL7 promotor, and secretion was directed by the secretion signals of yeast invertase. This construct yielded up to 6 mg propholipase A 2 activity per 1 fermentation broth, secreted as a glycosylated invertase prophospholipase A 2 hybrid protein. Upon genetically deleting the glycosylation site, the level of secretion decreased to 3.6 mg prosphospholipase A 2 per I. Changing the invertase secretion signals for an invertase/α-mating factor prepro sequence-fusion increased the secretion level up to 8 mg per I. The secreted non-glycosylated prosphospholipase A 2 species was correctly processed. Our results demonstrate the promises and limitations for rational design to obtain high level expression and secretion of heterologous protein by S. cerevisiae .