CLONING AND SURFACE EXPRESSION OF ANTIGEN F18 FUSED WITH M-CELL TARGETING PEPTIDE ON Saccharomyces cerevisiae CELL WALL

Abstract

Post-weaning diarrhea (PWD) is one of the most common diseases damaging the swine industry. Enterotoxigenic Escherichia coli (ETEC) is the main pathogen associated with PWD in piglets. The most important virulence is adhesion factors and enterotoxin. F4 and F18 are the two fimbriae frequently detected in ETEC. Vaccines offer a powerful, cost-effective and possible approach to protect pigs against ETEC. Recently, ETEC/F4 vaccine was available for commercial. On the other hand, ETEC/F18 vaccine still has to face many difficulties in development. To solve these problems, F18 antigene was fused to M-cell targeting protein PEP and displayed on Saccharomyces cerevisiae surface. This fusion was constructed by inserting the coding gene of pep-f18 into pGMIF1 plasmid. The recombinant plasmid named pGMIF1-pep-f18 was electroporated into a tryptophan auxotrophic Saccharomyces cerevisiae MT8-1 strain and was induced by glucose. The results showed that PEP-F18 protein was successfully expressed on the yeast cell surface, thus, succeeding in cloning an S. cerevisiae strain that expresses PEP-F18 on its cell wall. This was a starting material for later immunological evaluation.