氮源对酵母工程菌株生产α-淀粉酶的影响

Effect of Nitrogen Sources on α-Amylase Production in Recombinant Saccharomyces Cerevisiae 20B (pNA3)

在摇瓶培养条件下 ,研究了氮源对含重组质粒 p NA3的酿酒酵母 2 0 B- 12生产α-淀粉酶的影响。结果表明 :在葡萄糖去阻遏条件下必须有天然氮源存在 ,基因表达才能被诱导 ;几种天然氮源中酵母膏诱导效果最好 ,当酵母膏的添加量为 2 0 g/ L时 ,发酵液中α-淀粉酶的最大活力达 1.97U/ m L ,最大菌体密度为 0 .97g/L。各种天然氮源的添加量必须适中 。

The effect of nitrogen sources on α amylase production in S.cerevisiae strain 20B 12 harbouring recombinant plasmid pNA3 is developed in a shake flask culture.The results show that the production of gene product is performed by feeding natural nitrogen source during glucose is running out in the medium.The yeast extract is the most beneficial to α amylase production compared to other nitrogen source.The maximum enzyme activity and cell density are 1.97U/mL and 0.97g/L, respectively.The addition amount of nature nitrogen source must be optical,otherwise the cell growth and gene expression will be inhibited.