Thermostable amylase mutant and preparation method and application thereof

Abstract

The invention discloses a thermostable amylase mutant and a preparation method and application thereof, belonging to the field of genetic engineering. Bacillus stearothermophilus amylase is taken as a female parent, the N-terminal area of the bacillus stearothermophilus amylase and oligopeptide are connected through PT-linker so as to obtain the mutant, and the amino acid sequence of the oligopeptide is shown as SEQIDNO.1. Under the transformation condition, the bacillus stearothermophilus amylase is improved to be 7h from 4h of a comparison example (before mutation) in half-life period at 95DEG C. The method remarkably improves the thermostability of the amylase and provides a foundation for industrial production of the amylase.

Description

technical field

[0001] The invention relates to an amylase mutant and a preparation method thereof, in particular to a thermostable amylase mutant and a preparation method thereof. Background technique

[0002] Alpha-amylase, the systematic name is alpha-1,4-glucose-4-glucohydrolase. The characteristic of α-amylase is that it cuts the α-1,4 glycosidic bond in the middle of the starch molecular chain, and cannot hydrolyze the α-1,6 glycosidic bond, nor can it hydrolyze the α-1,4 glycosidic bond close to the 1,6 branch. The hydrolysis products are soluble dextrin, oligosaccharides and a small amount of maltose and glucose. α-amylase has considerable industrial application value and is widely used in alcohol, organic acid, amino acid and textile industries. The thermostable amylase-producing strains are obtained mainly through screening, mutagenesis and enzyme molecular modification. The blindness of the screening is large, and it is not easy to obtain the target strain. Mu...

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