title: Characterization of an aldo-keto reductase from Thermotoga maritima with high thermostability and a broad substrate spectrum.
abstract: A novel aldo-keto reductase gene, Tm1743, from Thermotoga maritima was overexpressed in Escherichia coli. The enzyme displayed the highest activity at 90 °C and at pH 9. It retained 63 % of its activity after 15 h at 85 °C. The enzyme also could tolerate (up to 10 % v/v) acetonitrile, ethanol and 2-propanol with slightly increased activities. Methanol, DMSO and acetone decreased activity slightly. Furthermore, Tm1743 exhibited broad substrate specificity towards various keto esters, ketones and aldehydes, with relative activities ranging from 2 to 460 % compared to the control. Its optimum substrate, 2,2,2-trifluoroacetophenone, was asymmetrically reduced in a coupled NADPH-regeneration system with an enantioselectivity of 99.8 % and a conversion of 98 %.
authors: Lab of Biocatalysis, Hangzhou Normal University, 402-Building D, 1378 West Wenyi Road, Hangzhou 311121, China.
authors: Yuan-Hui
authors: YH
authors: Ma
authors: Dan-Qing
authors: DQ
authors: Lv
authors: Shuo
authors: S
authors: Zhou
authors: Dun-Yue
authors: DY
authors: Lai
authors: Zhen-Ming
authors: ZM
authors: Chen
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry* / Q000378:metabolism*; D000449:Aldehyde Reductase; D000074408:Aldo-Keto Reductases; D004795:Enzyme Stability; D007700:Kinetics; D013237:Stereoisomerism; D013379:Substrate Specificity; D013696:Temperature; D020124:Thermotoga maritima / Q000201:enzymology*
chemical_list: D000429:Alcohol Oxidoreductases; D000074408:Aldo-Keto Reductases; D000449:Aldehyde Reductase