title: [Anaerobic synthesis of succinic acid by Escherichia coli strains with activated NAD+ reducing pyruvate dehydrogenase complex].
abstract: Effect of constitutive expression of the aceEF-lpdA operon genes coding for the enzymes of NAD+ reducing pyruvate dehydrogenase complex on the anaerobic production of succinic acids from glucose by recombinant Escherichia coli strains was studied. Basic producer strains were obtained by inactivation of the main pathways for synthesis of acetic and lactic acids by deletion of the genes ackA, pta, poxB, and ldhA (SGMO.1) in E. coli strain MG 1655 cells and additional introduction of the Bacillus subtilis pyruvate carboxylase (SG M0.1 [pPYC]). A constitutive expression of the genes aceEF-lpdA in derivatives of the basic strains SGM0.1 PL-aceEF-lpdA and SGM0.1 PL-aceEF-lpdA [pPYC] was provided by replacing the native regulatory region of the operon with the lambda phage PL promoter. Molar yields of succinic acid in anaerobic glucose fermentation by strains SGM0.1 P(L)-aceEF-lpdA and SGM0.1 PL-aceEF-lpdA [pPYC] exceeded the corresponding yields displayed by several control strains (exceeded considerably in the case of the strains with a pyruvate carboxylase activity). It is concluded that an increase in the succinic acid production by strain SGM0.1 PL-aceEF-lpdA [pPYC] as compared with the strains SGM0.1 and SGM0.1 [pPYC], which synthesize this substance in the reductive tricarboxylic acid cycle, is determined by activation of the glyoxylate shunt.
authors.forename: A Iu
authors.initials: AIu
authors.lastname: Skorokhodova
authors.forename: A Iu
authors.initials: AIu
authors.lastname: Gulevich
authors.forename: A A
authors.initials: AA
authors.lastname: Morzhakova
authors.forename: R S
authors.initials: RS
authors.lastname: Shakulov
authors.forename: V G
authors.initials: VG
authors.lastname: Debabov
mesh_terms: D000693:Anaerobiosis; D001412:Bacillus subtilis / Q000737:chemistry / Q000201:enzymology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D010582:Bacteriophage lambda / Q000235:genetics / Q000378:metabolism; D002952:Citric Acid Cycle; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005285:Fermentation; D017353:Gene Deletion; D015870:Gene Expression; D005818:Genetic Engineering / Q000379:methods*; D005947:Glucose / Q000378:metabolism*; D006038:Glyoxylates / Q000378:metabolism; D009243:NAD / Q000378:metabolism*; D009876:Operon; D010957:Plasmids; D011401:Promoter Regions, Genetic; D011766:Pyruvate Carboxylase / Q000235:genetics / Q000378:metabolism*; D011768:Pyruvate Dehydrogenase Complex / Q000235:genetics / Q000378:metabolism*; D019802:Succinic Acid / Q000302:isolation & purification / Q000378:metabolism; D014162:Transfection
chemical_list: D001426:Bacterial Proteins; D006038:Glyoxylates; D011768:Pyruvate Dehydrogenase Complex; D009243:NAD; D019802:Succinic Acid; D011766:Pyruvate Carboxylase; D005947:Glucose