A kind of ketoreductase mutant and its preparation method

Abstract

The invention relates to a ketone reductase mutant and a preparation method thereof. The ketone reductase mutant comes from a saccharomyces cerevisiae wild type ketone reductase, is capable of converting 5-hydroxyl-3-oxohexanoate into corresponding cis 3,5-dihydroxylhexanoate, and has one or more mutants of I46V, S127N and Q144K. The ketone reductase mutant has obvious high specific enzyme activity which is improved by 2-100 times compared with that of the wild type ketone reductase, can be utilized to biologically catalyze 5-hydroxyl-3-oxohexanoate to product corresponding cis 3,5-dihydroxylhexanoate. The reaction conditions are mild, requirements on equipment are low, the production process does not need high temperature or cooling, and energy consumption is low. Because enzyme catalysis has efficient specific selectivity, the process of producing the statin medicine key intermediate cis 3,5-dihydroxylhexanoate, does not generate by-products, and purification is convenient. Additionally, the solvent employed in the reaction is mainly water, "three wastes (waste gas, waste water and industrial residue)" discharge is low, and the reaction is green and environment-friendly.

Description

technical field [0001] The invention relates to a ketoreductase mutant and a preparation method thereof, in particular to a ketoreductase mutant derived from Saccharomyces cerevisiae and an efficient preparation method thereof. Background technique [0002] Atorvastatin calcium (trade name LIPITOR sold by Pfizer), rosuvastatin calcium (trade name CRESTOR sold by AstraZeneca) and pitavastatin (trade name Lipalo sold by Nissan Chemical and Kowa in Japan), Is an important cholesterol-lowering statin drugs. Stereomerically pure cis-3,5-dihydroxyhexanoate is the key chiral intermediate of these important statins. The many routes known to prepare these chiral intermediates, both chemical and enzymatic, suffer from a number of disadvantages. Due to harsh conditions in the chemical synthesis process, many side reactions, difficulty in product separation and purification, low yield, and high cost, it is difficult to become an ideal method for commercial-scale synthesis. Enzymatic ...

AI Technical Summary

Problems solved by technology

Due to harsh conditions in the chemical synthesis process, many side reactions, difficult separation and purification of products, low yield and high cost, it is difficult to become an ideal method for commercial scale synthesis

Enzymatic preparation of stereoisomerically pure cis-3,5-dihydroxyhexanoate requires the use of stereoselective ketoreductase, but the catalytic activity of the existing wild-type ketoreductase is very low, and the use of 10g / L Crude enzyme powder can only convert 1g / L of ketone substrate in 20 hours, which also makes it difficult to be an ideal method for commercial scale synthesis