提高酵母菌 Pichia pastoris 蛋白表達系統的重組蛋白產量

Pichia pastoris is a well known expression system of recombinant proteins, and has been widely used to express various heterologous proteins. It offers the potential of secretion of recombinant protein and simplifying the purification steps because P. pastoris secretes only low levels of endogenous proteins. However, the native secretion signal sequence of a foreign may or may not function properly in P. pastoris. Although several different secretion signal sequences have been used successfully, a choice of the specific secretion signal for a particular target protein must be made to obtain high secretion levels in P. pastoris. In this study, nine secretion signal sequences were respectively incorporated into a P. pastoris vectors which express the recombinant secretory Candida rugosa lipases with different secretion signal peptide. Among the transformants that have single copy of integrated foreign gene, the secretion signal sequence from Gallus gallus lysozyme is suitable for optimal expression and secretion of the recombinant lipase. The protein secretion level of this signal was 10 times higher than the minimal one in this study. The result indicates that secretion signal engineering is feasible to improve the production of a recombinant protein in P. pastoris.