Recombinant strain Escherichia coli BL21(pET-eryKR1)2, which heterologously expressed ketoreductase in the first module of polyketide synthase from Saccharopolyspora erythraea, fermented with 1,2-cyclohexanedione as reduction substrate. In that reaction, the reduced product of substrate was 2-hydroxycyclohexanone, its single carbonyl was reduced. The conditions with substrate concentration of 20 mmol/L, cell density of 80 g/L, pH of 6. 0, rotation speed of 120 r/min and reaction temperature of 37 ℃ were optimal for this biocatalytic conversion with the addition of 10 g/L of coenzyme regeneration system E. coli BL21 ( pET-gdh1 ) and 0. 2 mmol/L of NADPH. The conversion rate of 1 ,2-cyclohexanedione catalyzed by the recombinant cells for 10 h could reach 84. 2% under these conditions.%利用表达糖多孢红霉菌聚酮合成酶模块1的酮还原酶的重组大肠杆菌细胞Escherichia coli BL21( pET-eryKR1)2对1,2-环己二酮进行了催化还原反应,该还原反应为单羰基还原而非双羰基还原,生成的产物为2-羟基环己酮。对重组细胞催化1,2-环己二酮还原的反应条件进行了优化,发现最优的反应条件为底物浓度20 mmol/L,细胞密度80 g/L, pH 6．0,转速120 r/min,温度37℃,且需要添加10 g/L E． coli BL21(pET-gdh1)辅酶再生系统和0．2 mmol/L NADPH。在该反应条件下,重组菌催化反应10 h后,底物的转化率可高达84．2%。
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