High-yield kestose synanthrin sucrase mutant

• Main Authors: MU WANMENG, ZHANG WENLI, NI DAWEI, XU WEI
• Format: Patent
• Language: Chinese; English
• Published: 03.08.2021
• Subjects: BEER; BIOCHEMISTRY; CHEMISTRY; COMPOSITIONS THEREOF; CULTURE MEDIA; ENZYMOLOGY; FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIREDCHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERSFROM A RACEMIC MIXTURE; METALLURGY; MICROBIOLOGY; MICROORGANISMS OR ENZYMES; MUTATION OR GENETIC ENGINEERING; PROPAGATING, PRESERVING OR MAINTAINING MICROORGANISMS; SPIRITS; VINEGAR; WINE

The invention discloses a high-yield kestose synanthrin sucrase mutant, and belongs to the technical field of genetic engineering of enzymes. According to the invention, a single-point mutant enzyme R425W is constructed by taking synanthrin sucrase which is derived from a microorganism Lactobacillus reteri 121 and is obtained through partial sequence truncation as a parent. The R425W significantly changes the chain length of the product, so that the synanthrin sucrase loses the polysaccharide synthesis capability, and a large amount of fructo-oligosaccharide, especially kestose, is accumulated. Through optimization of reaction conditions, the yield of kestose produced by R425W can reach 206g/L. The production conditions are as follows: the pH is 6.5, the temperature is 45 DEG C, the sucrose is 700g/L, the enzyme addition amount is 15mu g/mL, and the reaction time is 36h. The discovery has important research value for industrial preparation of kestose and industrial application of synanthrin sucrase. 本发明公开了一种高