Mutations in the stereospecificity pocket and at the entrance of the active site of Candida antarctica lipase B enhancing enzyme enantioselectivity
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چکیده
18 Two different parts of Candida antarctica lipase B (stereospecificity pocket at the bottom of 19 the active site and hydrophobic tunnel leading to the active site) were redesigned by single-or 20 double-point mutations, in order to better control and improve enzyme enantioselectivity 21 toward secondary alcohols. Single point isosteric mutations of Ser47 and Thr42 situated in the 22 stereospecificity pocket gave rise to variants with doubled enantioselectivity toward pentan-223 ol, in solid/gas reactor. Besides, the width and shape of the hydrophobic tunnel leading to the 24 active site was modified by producing the following single-point mutants: Ile189Ala, 25 Leu278Val and Ala282Leu. For each of these variants a significant modification of 26
منابع مشابه
Rational redesign of Candida antarctica lipase B
This thesis describes the use of rational redesign to modify the properties of the enzyme Candida antarctica lipase B. Through carefully selected single-point mutations, we were able to introduce substrate-assisted catalysis and to alter the reaction specificity. Other single-point mutations afforded variants with greatly changed substrate selectivity and enantioselectivity. Mutation of the cat...
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