头孢菌素C去乙酰基酶产生菌的筛选、酶学性质及产酶条件优化

Screening and identification of CAH-producing strain, enzyme properties of cephalosporin-C deacetylase and optimization of enzyme production

以7-ACA为底物从土壤中筛选得到一株产头孢菌素C乙酰水解酶的微生物,初步鉴定为红酵母。酶学性质研究表明:静息细胞CAH的最适pH为7.0,最适反应温度为25℃;在温度低于40℃保存静息细胞时CAH的稳定性很好,在pH 5.5～8.0的范围内保存静息细胞时CAH比较稳定。产酶条件优化结果为:葡萄糖30g/L,国产酵母粉20 g/L,KH_2PO_4 5g/L,培养基的最优初始pH为7.0。

When 7-aminocephalosporanic acid （7-ACA） was used as a single carbon source in the enrichment culture medium for screening 7-ACA-degrading microorganisms, a strain producing CAH with high yield was obtained. It was identified as red yeast. The enzyme was most active at 25℃ and pH 7.0. The enzyme was stable at temperatures lower than 40℃ and within pH 5.5-8.0. The optimized conditions for enzyme production were as followings： glucose 30 g/ L, homemade yeast 20 g/L and KH2PO45 g/L, while the initial medium pH was 7.0.