Industrial saccharomyces cerevisiae metabolic engineering bacterium with low yield of citrulline

Abstract

The invention discloses an industrial saccharomyces cerevisiae metabolic engineering bacterium with a low yield of citrulline and belongs to the technical field of fermentation and biotechnology. A method comprises the following steps: taking saccharomyces cerevisiae uracil auxotroph recovery as a screening marker for constructing a gene deletion ARG3L-URA3-ARG3R of an encoding gene ARG3 of ornithine carbamoyl transferase; converting into a uracil auxotroph haploid; and inserting a complete saccharomyces cerevisiae URA3 gene into an opening reading frame of the saccharomyces cerevisiae genome ARG3 through homologous recombination, thereby acquiring the haploid engineering bacterium without the ARG3 gene. The yeast engineering bacterium acquired according to the method is a prototrophy bacterial strain, contains no exogenous gene and has bio-security; the growth and fermentation properties of the engineering bacterium are similar to those of the original strain in a rice juice fermentation process, but the content of citrulline is reduced by 39.0%; and a new idea for reducing the EC content in industrial production is provided.

Description

technical field [0001] The invention relates to an industrial Saccharomyces cerevisiae metabolic engineering bacteria with low citrulline production, which belongs to the field of fermentation and biotechnology. Background technique [0002] Ethyl Carbamate (EC for short), commonly known as urethane, widely exists in fermented food (such as fermented bean curd, soy sauce, etc.), brewed wine (such as Chinese rice wine, Japanese sake, wine, cider, etc.) and distilled wine (such as whiskey, brandy, etc.). With the continuous detection of EC in a variety of alcoholic beverages and people's emphasis on the concept of healthy diet, the existence of EC is not only a health hazard for consumers, but also hinders the pace of internationalization of rice wine in my country. Therefore, it is particularly important to control the content of EC in rice wine. [0003] During the production of rice wine, urea and citrulline produced by the metabolism of microorganisms such as Saccharomyc...

AI Technical Summary

Problems solved by technology

In wine, citrulline, like urea, reacts with ethanol as the main precursor to form EC. In soy sauce, citrulline plays a leading role in the formation of EC. In rice wine, citrulline acts as a precursor to form EC. The mechanism of citrulline has not yet drawn a unified conclusion, and there are few reports on the effect of citrulline metabolic pathway of Saccharomyces cerevisiae on the content of citrulline in rice wine fermentation broth

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