Abstract: Yeast is a type of widely used eukaryotic microorganism easy to do genetic manipulation and fermentation, which has capability to secrete and modify foreign proteins. Its advantages of rapid growth, high safety and high density fermentation are significant for foreign proteins industrial productions. In some cases, however, the production of foreign proteins in yeast system is often limited by some endogenous factors. Recently, many researches have focused on engineering of fermentation process, vector systems and host strains, which effectively overcome the disadvantages in the yeast secretion pathway. At present, engineering strategies for yeast strains focus on yeast secretion system, protease degradation and glycosylation. Yeast secretion system involves many crossreacting factors making its genetic modification more complicated. The recent strategies for yeast secretion system and their advantages are reviewed in this article.

Key words: yeast, secretion system, protein folding, protein trafficking