通过定点突变提高胆固醇氧化酶的热稳定性和酶活性。

Improvement of the thermostability and enzymatic activity of cholesterol oxidase by site-directed mutagenesis.

机构信息

The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People's Republic of China.

出版信息

Biotechnol Lett. 2011 Oct;33(10):2049-55. doi: 10.1007/s10529-011-0669-6. Epub 2011 Jun 24.

DOI:10.1007/s10529-011-0669-6

PMID:21701916

Abstract

Site-directed mutagenesis was applied to enhance the thermostability and enzymatic activity of cholesterol oxidase (ChOx) isolated from Brevibacterium sp. Three amino acid residues (Q153E, F128L, and S143H) located near the FAD-binding site of the enzyme were substituted based on structural analysis. The specific activity of the two-sites mutant Q153E/F128L increased by 11.6% and the relative activity increased by 47% when grown for 2 h at 50 °C. This mutant is a potential industrial strain for producing ChOx.

摘要

定点突变被应用于增强从 Brevibacterium sp. 中分离的胆固醇氧化酶 (ChOx) 的热稳定性和酶活性。根据结构分析，替换了位于酶的 FAD 结合位点附近的三个氨基酸残基 (Q153E、F128L 和 S143H)。在 50°C 下培养 2 小时后，双突变体 Q153E/F128L 的比活性增加了 11.6%，相对活性增加了 47%。该突变体是生产 ChOx 的潜在工业菌株。