S-扁桃酸脱氢酶基因的克隆及表达

Cloning and Expression of S-mandelate Dehydrogenase Gene

S-扁桃酸脱氢酶能够选择性催化S-扁桃酸生成苯甲酰甲酸。通过PCR扩增获得Pseudomonas putida NUST的S-扁桃酸脱氢酶全长基因(mdlA),并构建了表达载体pET30a(+)-mdlA,转化大肠杆菌E.coli BL21(DE3)后,经异丙基-β-D-硫代吡喃半乳糖苷(IPTG)诱导获得表达,SDS-PAGE结果显示表达蛋白为43kDa。所以工程菌细胞具有转化S-扁桃酸生成苯甲酰甲酸能力。

S-mandelate dehydrogenase （SMDH） can catalyze S-mandelic acid to benzoylformic acid. The SMDH nucleotide gene（mdlA）was cloned from DNA of Pseudomonas putida NUST by PCR, and the amplicon was inserted into prokaryotic expression vector pET-30a （ ＋ ）. This recombinant was transformed into E. coli BI21 （ DE3 ） and then highly expressed by induction of IPTG. The result of SDS-PAGE showed that the molecular weight of cloned SMDH was about 43kDa. The recombinant strain could catalyze S-mandelate to benzoylformic acid.