Genetically engineered bacteria to produce the DL- alanine, and a method for producing DL- alanine by the use of the genetic engineering bacteria

摘要

The present invention discloses a DL- alanine production genetically engineered bacteria. Lactate dehydrogenase of this DL- alanine production genetically engineered bacteria itself, pyruvate formate lyase, alcohol dehydrogenase, acetate kinase, fumarate reductase, alanine racemase, and to inactivate the methylglyoxal synthase, furthermore, exogenous L- alanine in the chromosome incorporate dehydrogenase gene and exogenous alanine racemase gene. In the present application, by incorporating the exogenous L- alanine dehydrogenase gene on the chromosome of the genetic manipulation bacteria, pyruvate is an intermediate of glycolysis is converted to L- alanine, by further incorporating an exogenous alanine racemase gene, by converting a portion of the L- alanine to D- alanine, to produce directly DL- alanine from raw materials polysaccharides. Accordingly, shortening the production cycle of DL- alanine, increasing the yield of DL- alanine.BACKGROUND