Syal Poonam, Gupta Rani
Department of Microbiology, University of Delhi South Campus, New Delhi, 110021, India.
Appl Biochem Biotechnol. 2015 May;176(1):110-24. doi: 10.1007/s12010-015-1561-y. Epub 2015 Mar 25.
A novel lipase gene, ylip9, of Yarrowia lipolytica MSR80 was cloned and expressed in pEZZ18-HB101 system and was 99% identical to YLIP9 of Y. lipolytica CLIB122. It was purified using IgG-Sepharose as ZZ fused YLIP9 and had specific activity of 0.8 U/mg. ZZ-YLIP9 was most active at pH 8.0 and 70 °C. It was stable over a wide pH range of 3.0-11.0 and 100 % active at 70 °C up to 2 h and had t1/2 of 286.42 min at 80 °C. It showed high specificity toward p-nitrophenyldecanoate with kcat and catalytic efficiency of 30.17 s(-1) and 16.67 mM(-1) s(-1), respectively. It was non-regioselective, but an S-enantioselective lipase and the percentage conversion were enhanced in presence of hexane. ZZ-YLIP9 was stable in all of the organic solvents used, and its activity was enhanced by solvents having logP value less than 2.
克隆了解脂耶氏酵母MSR80的一个新脂肪酶基因ylip9，并在pEZZ18-HB101系统中进行表达，其与解脂耶氏酵母CLIB122的YLIP9有99%的同一性。使用IgG-琼脂糖作为ZZ融合的YLIP9对其进行纯化，其比活性为0.8 U/mg。ZZ-YLIP9在pH 8.0和70℃时活性最高。它在3.0-11.0的宽pH范围内稳定，在70℃下2小时内活性保持100%，在80℃下的半衰期为286.42分钟。它对对硝基苯基癸酸酯表现出高特异性，kcat和催化效率分别为30.17 s(-1)和16.67 mM(-1) s(-1)。它是非区域选择性的，但却是一种S-对映体选择性脂肪酶，在己烷存在下转化率提高。ZZ-YLIP9在所使用的所有有机溶剂中都很稳定，并且其活性在logP值小于2的溶剂中增强。
