一株产(-)γ-内酰胺酶的Pantoea Ananatis Y22筛选及全细胞转化(+/-)γ-内酰胺

Isolation of Pantoea Ananatis Y22 with (-) γ-Lactamase and WholeCell Resolution of Racemic γ-Lactam

利用(+/-)γ-内酰胺做为唯一碳源从土壤中分离出一株能产生(+)γ-内酰胺酶水解拆分(+/-)γ-内酰胺的菌株。鉴定菌株为Pantoea ananatis Y22。进一步优化了P.ananatis Y22发酵产γ-内酰胺酶的发酵条件和生物转化条件。发现棉子糖为最佳碳源,蛋白胨为最佳氮源;Y22在p H值4~10范围内生长良好,最佳发酵p H值为7,最佳生物转化p H值为8。确定最佳发酵温度为30℃,最佳生物转化温度为30℃。

We isolated a strain that can produce(-)γ-lactamase to hydrolyze racemic(+/-)γ-lactam from several soil samples,using(+/-)γ-lactam as the only source of carbon.We identified this strain to be Pantoea ananatis Y22.We further optimized the enzyme fermentation and biotransformation conditions for theγ-lactamase from P.ananatis Y22.We found that glucose was the optimum carbon source and ammonium oxalate the optimal nitrogen source;P.ananatis Y22 showed good growth at pH values raning from 4 to 10,with an the optimum fermentation pH was 7,the optimum biotransformation pH was 8.The optimum fermentation temperature was determined to be 30℃and the optimal biotransformation temperature was 30℃.