Genetic engineering bacteria for producing L-lactic acid from acetic acid, construction method thereof and application thereof

Abstract

The invention discloses genetic engineering bacteria for producing L-lactic acid from acetic acid, a construction method thereof and application thereof. The genetic engineering bacteria for producingL-lactic acid from acetic acid are obtained by modifying the recipient bacteria as follows: knocking out the poxB gene, pflB gene, aceEF gene, ldhA gene and lldD gene of the recipient bacteria; and increasing the content of protein encoded by the acs gene, pta gene, ackA gene, aceA gene, aceK gene, aceB gene, maeA gene, maeB gene, and ldh2 gene in the recipient bacteria. According to the engineering bacteria obtained by the invention, the desired level of the yield of L-lactic acid obtained by using acetic acid in shake flask culture is achieved, the use of carbon sources such as glucose is avoided, the reduction of the raw material cost of L-lactic acid fermentation is facilitated, and good application prospects are realized.

Description

technical field [0001] The invention belongs to the fields of biotechnology, genetic engineering and fermentation engineering, and specifically relates to a genetically engineered bacterium for producing L-lactic acid using acetic acid, a construction method and application thereof. Background technique [0002] Human society consumes a large amount of fossil resources such as oil and coal every year, and the resulting emission of a large amount of greenhouse gases has caused concerns about climate change. Therefore, the development and utilization of renewable biomass resources has become one of the hot spots in the current scientific and industrial circles. At present, glucose, xylose, starch, and cellulose derived from agriculture and planting are carbon sources and energy materials commonly used by microorganisms in the fermentation industry. my country is a big country in the bio-fermentation industry. The output of many products ranks first in the world, and consumes ...

AI Technical Summary

Problems solved by technology

Although there have been some studies on the fermentation of lactic acid from non-grain and cheap raw materials such as cellulose, cassava, molasses, and Jerusalem artichoke, cornstarch is still the main raw material used in large-scale fermentation, which leads to the high market price of L-lactic acid and limits the production of lactic acid. Its wide application in biodegradable materials and other fields

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