High-yield acetate brewing yeast engineering bacteria

Abstract

The invention relates to high-yield acetate brewing yeast engineering bacteria; a method for preparing the brewing yeast bacteria provided by The invention comprises the following steps: selecting strong promoters PGK1 so as to overexpress ATF2 gene coding alcohol acetyl transferase, thereby obtaining high-yield acetate brewing yeast engineering bacteria SaccharomycescerevisiaeEY-14, wherein a preservation number is CGMCC (China General Microbiological Culture Collection Center) No.5635. According to The invention, on a condition that other fermenting performance is not influenced, transformant bacterial strains are compared with parent strains (SaccharomycescerevisiaeCGMCC No 2.1525); after simulation of semi-solid fermentation, the content of ethyl acetate is increased by 3.6 times; the content of isoamyl acetate is increased to 55.2mg / L; the content of isobutyl acetate is increased to 33.8mg / L; the sifted engineering bacteria has no specific demand for fermentation equipment and conditions; the equipment and conditions of normal white sprits factories can be used; therefore, the engineering bacteria has wide application propose and brings marked economic benefit to industrial production of the white sprits factories.

Description

technical field

[0001] The invention belongs to the technical field of bioengineering, and relates to the breeding of industrial microorganisms, in particular to a high-yielding acetate-producing Saccharomyces cerevisiae engineered bacterium. Background technique

[0002] Rice wine and baijiu are the special wines in my country. Domestic common baijiu and rice wine are mainly fermented by purebred S. The capacity is extremely low, resulting in poor quality of finished wine. The main reason for the high content of ester aroma substances in high-grade beverage wine (yellow wine, white wine) is that natural koji-making microorganisms are used to make koji fermentation. Increase the ester content in wine, and the existence of these wild yeasts seriously affects the yield of raw materials, and its alcohol fermentation efficiency is less than one-third of that of Saccharomyces cerevisiae, which leads to high grain consumption, long production cycle and low efficiency of my country'...

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