Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China.
Steroids. 2011 Sep-Oct;76(10-11):1136-40. doi: 10.1016/j.steroids.2011.05.001. Epub 2011 May 10.
A thermostable 7α-hydroxysteroid dehydrogenase from Bacteroides fragilis ATCC 25285 was found to catalyze the reduction of various benzaldehyde analogues to their corresponding benzyl alcohols. The enzyme activity was dependent upon the substituent on the benzene ring of the substrates. Benzaldehydes with electron-withdrawing substituent usually showed higher activity than those with electron-donating groups. Furthermore, this enzyme was tolerant to some organic solvents. These results together with previous studies suggested that 7α-hydroxysteroid dehydrogenase from B. fragilis might play multiple functional roles in biosynthesis and metabolism of bile acids, and in the detoxification of xenobiotics containing carbonyl groups in the large intestine. In addition, its broad substrate spectrum offers great potential for finding applications not only in the synthesis of steroidal compounds of pharmaceutical importance, but also for the production of other high-value fine chemicals.
从脆弱拟杆菌 ATCC 25285 中发现了一种热稳定的 7α-羟甾醇脱氢酶，它能够催化各种苯甲醛类似物还原为相应的苄醇。酶活性取决于底物苯环上的取代基。具有吸电子取代基的苯甲醛通常比具有供电子基团的苯甲醛具有更高的活性。此外，这种酶对一些有机溶剂具有耐受性。这些结果与之前的研究表明，脆弱拟杆菌的 7α-羟甾醇脱氢酶可能在胆汁酸的生物合成和代谢以及在大肠中含有羰基的外来化合物的解毒中发挥多种功能作用。此外，其广泛的底物谱为寻找应用提供了巨大的潜力，不仅可用于合成具有重要药物意义的甾体化合物，还可用于生产其他高价值的精细化学品。
