恶臭假单胞菌产羰基还原酶的发酵条件优化

Optimization of fermentation conditions for carbonyl reductase production by Pseudomonas putida

从土样中筛选得到一株产羰基还原酶的菌种恶臭假单胞菌(Pseudomonas putida)ZJPH1606,该菌能不对称催化2'-三氟甲基苯乙酮合成(R)-1-(2-三氟甲基苯基)乙醇,对映体过量值超过99.0%.通过单因素考察产酶培养基组成发现:葡萄糖、牛肉膏和MgSO_4·7H_2O对酶活的影响较为明显,进一步采用响应面法对产酶培养基进行了优化.结果表明:最优发酵培养基组成为葡萄糖38.5g/L,牛肉膏32.7 g/L,MgSO_4·7H_2O 1.1 g/L.在最适培养条件下,菌体酶活力达0.31 U/g,较优化前提高了71.0%.该研究结果丰富了羰基还原酶数据库的基因序列,为高效合成(R)-1-(2-三氟甲基苯基)乙醇提供了新途径.

A bacterial strain Pseudomonas putida ZJPH1606 containing carbonyl reductase was screened out from soil,which can reduce 2'-(Trifluoromethyl) acetophenone to(R)-1-[2-(trifluoromethyl)phenyl] ethanol with enantiomeric excess(e.e.) higher than 99.0%.By single factor experiment,glucose,beef extract and MgSO_4·7 H_2O were found to be significant factors influencing the carbonyl reductase production.In order to improve the enzyme production,the medium components were further optimized by response surface methodology.The results showed that the enzyme activity reached highest when the fermentation medium was composed of glucose 38.5 g/L,beef extract 32.7 g/L,MgSO_4·7 H_2O1.1 g/L.Under the optimum conditions,the enzyme activity reached 0.31 U/g,increased by 71.0%compared to the original medium components.This study enriched the gene sequences database of carbonyl reductase and provided a new approach for the efficient synthesis of(R)-1-[2-(trifluoromethyl)phenyl] ethanol.