Study on Mesophilic and Thermophilic Alcohol Dehydrogenases in Gas‐Phase Reaction
Study on Mesophilic and Thermophilic Alcohol Dehydrogenases in Gas‐Phase Reaction
复制标题
中温和高温乙醇脱氢酶的气相反应研究
DOI：
10.1021/bp050316g
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发表时间：
2006
影响因子：
2.9
通讯作者：
J. Büchs
中科院分区：
文献类型：
--
作者：
A. Trivedi;A. Spiess;T. Daussmann;J. Büchs
研究了短链乳杆菌(LBADH)产的嗜中性醇脱氢酶(ADH)和嗜热厌氧菌产的嗜热性ADH的起始反应速率和热稳定性。(ADH-T)进行了比较。研究了水的活度、辅因子与蛋白质的摩尔比、反应温度对苯乙酮还原为1-苯乙醇的影响。就生产力而言，两种ADHS的最佳水分活度均为0.55。辅因子与蛋白质的摩尔比略高于等摩尔，以提高活性和热稳定性。在60℃时，LBADH和ADH T的最适产量分别为1000g·L−1·d−1和600g·L−1·d−1，而在30℃时酶的总周转量最高，分别达到420万和170万。有趣的是，短链球菌的ADH在非常规中相中表现出较高的热稳定性。
The initial reaction rate and the thermostability of the mesophilic alcohol dehydrogenase (ADH) from Lactobacillus brevis (LBADH), and the thermophilic ADH from Thermoanaerobacter sp. (ADH T) in gas‐phase reaction were compared. The effects of water activity, cofactor‐to‐protein molar ratio, and reaction temperature on the reduction of acetophenone to 1‐phenylethanol were studied. An optimal water activity of 0.55 in terms of productivity was found for both ADHs. The cofactor‐to‐protein molar ratio was chosen slightly higher than equimolar to increase both activity and thermostability. An excellent optimal productivity of 1000 g·L−1·d−1 for LBADH and 600 g·L−1·d−1for ADH T was found at 60 °C, while the highest total turnover numbers with respect to the enzyme were achieved at 30 °C and amounted to 4.2 million for LBADH and 1.7 million for ADH T, respectively. Interestingly, the ADH from the mesophilic L. brevis showed the higher thermostability in the nonconventional medium gas phase.