中文摘要：

以巨大芽孢杆菌Z2013513基因组DNA为模板，分别PCR扩增得到L-乳酸脱氢酶基因（ldhL）和葡萄糖脱氢酶基因（gdh），将gdh与ldhL分别连接至表达载体pETDuet，获得共表达质粒pETDuet-ldhL-gdh。经转化和验证获得重组菌大肠杆菌BL21（DE3）/pETDuet-ldhL-gdh。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳和比酶活力分析表明重组蛋白L-乳酸脱氢酶和葡萄糖脱氢酶均成功表达且具有酶活力。在37℃、200r/min条件下，经60min反应，催化底物苯丙酮酸合成24.26mmol/LL-苯基乳酸。产物L-苯基乳酸光学纯度（＞99%），底物摩尔转化率（59.55%），结果表明此重组体系可用于高效合成高光学纯L-苯基乳酸。

英文摘要：

The L-lactate dehydrogenase gene (ldhL) and glucose dehydrogenase gene (gdh) were respectively amplified from Bacillus megaterium Z2013513 by PCR and inserted into the plasmid pETDuet-1 to construct the recombinant vector pETDuet-ldhL-gdh. Then, the vector was transformed into Escherichia coli BL21 (DE3) to obtain the recombinant strainE. coli BL21(DE3)/pETDuet-ldhL-gdh. Sodium dodecyl sulfate polyacrylamide gel electrophoresis and enzymatic activityanalysis showed that both ldhL and gdh were successfully co-expressed with biological functions in the recombinant strain.Using whole cells of recombinant E. coli BL21(DE3)/pETDuet-ldhL-gdh, 24.26 mmol/L L-phenyllactic acid was obtained from phenylpyruvic acid at 37 ℃ and 200 r/min after 60 min transformation. The product enantiomeric excess percent was over 99% with substrate molar conversion rate of 59.55%. The results showed the cofactor regeneration biotransformation system was capable of efficiently producing optically pure L-phenyllactic acid.