利用毕赤酵母系统直接分泌表达具有活性的谷氨酰胺转胺酶

Direct secretory expression of active microbial transglutaminase in Pichia pastoris

摘要:

使用异源表达系统直接分泌表达具有活性的微生物谷氨酰胺转氨酶 (Microbial transglutaminase，MTG) 是目前最具前景的MTG生产方法之一，但由于产量较低无法实现工业化生产。毕赤酵母是近年来发展出的高效蛋白表达系统。通过采用pro序列与成熟MTG基因共表达的策略，成功地实现了用重组毕赤酵母分泌表达具有活性的茂原链霉菌Streptomyces mobaraense MTG。进一步通过对pro序列和MTG基因拷贝数以及重组酵母培养条件的优化，最终使得MTG在1 L发酵罐中高密度发酵的酶活达到7.3 U/mL，为MTG的工业化生产奠定了基础。

Abstract:

Direct secretory expression of active microbial transglutaminase (MTG) using heterologous hosts is a promising strategy, although its production level still needs to be improved for industrial production. Pichia pastoris is one of the most efficient expression systems developed in recent years. In this study, secretory expression of active MTG was successfully achieved by co-expressing the pro sequence and mature MTG genes in P. pastoris. Furthermore, we optimized the copy number of pro/MTG expression cassettes and the fermentation conditions. MTG production level reached 7.3 U/mL in 1-liter fermentor through high density fermentation, providing the feasiblity for industrial scale preparation of MTG.