Application of entrapped growing yeast cells to peptide secretion system

Abstract

Efficient production of α-mating factor with immobilized growing Saccharomyces cerevisiae cells was examined in order to establish a secretion system for useful peptides using the α-mating factor secretion system. The free yeast cells produced α-mating factor into the cultured medium, but α-mating factor was gradually degraded in situ. Based on the criteria of α-mating factor productivity, cell growth in gels, cell leakage from gels, and mechanical strength of gels, a mixture of a hydrophilic neutral photo-crosslinkable resin prepolymer (ENT-2000) and an anionic prepolymer (ENTA-2) (8:2 by weight) was employed as gel material, among various kinds of natural and synthetic supports, to entrap the yeast cells. Anionic photo-crosslinkable resins selectively entrapped α-mating factor-degrading enzymes which were produced by the cells and degraded α-mating factor formed. The immobilized growing yeast cells could be used successfully for continuous production of α-mating factor in a packed column reactor for at least 30 days.