Flux through the tetrahydrodipicolinate succinylase pathway is dispensable for L-lysine production in Corynebacterium glutamicum

• Published in: Applied microbiology and biotechnology Vol. 51; no. 3; pp. 325 - 333
• Main Authors: SHAW-REID, C. A, MCCORMICK, M. M, SINSKEY, A. J, STEPHANOPOULOS, G
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01-03-1999; Springer Nature B.V
• Subjects: Acyltransferases - genetics; Acyltransferases - metabolism; Amidohydrolases - genetics; Amidohydrolases - physiology; Amino Acid Oxidoreductases - genetics; Amino Acid Oxidoreductases - metabolism; Bacteria; Bacteriology; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; Corynebacterium - genetics; Corynebacterium - growth & development; Corynebacterium - metabolism; Dehydrogenase; Dehydrogenases; Enzymes; Fundamental and applied biological sciences. Psychology; Glucose - metabolism; Lysine - biosynthesis; Mission oriented research; Mutagenesis; Physiology and metabolism; Time Factors; Transformation, Bacterial - genetics; Acyltransferases; Enzyme; Transferases; Gene overexpression; Metabolic pathway; 2,3,4,5-Tetrahydropyridine-2-carboxylate N-succinyltransferase; Lysine; Corynebacterium glutamicum; Production; Microorganism culture; Diaminopimelate dehydrogenase; L stereoisomer; Bacteria; Actinomycetes; Corynebacteriaceae; Oxidoreductases; Mutation; Comparative study
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s002530051398

The N-succinyl-LL-diaminopimelate desuccinylase gene (dapE) in the four-step succinylase branch of the L-lysine biosynthetic pathway of Corynebacterium glutamicum was disrupted via marker-exchange mutagenesis to create a mutant strain that uses only the one-step meso-diaminopimelate dehydrogenase branch to overproduce lysine. This mutant strain grew and utilized glucose from minimal medium at the same rate as the parental strain. In addition, the dapE- strain produced lysine at the same rate as its parent strain. Transformation of the parental and dapE- strains with the amplified meso-diaminopimelate dehydrogenase gene (ddh) on a plasmid did not affect lysine production in either strain, despite an eightfold amplification of the activity of the enzyme. These results indicate that the four-step succinylase pathway is dispensable for lysine overproduction in shake-flask culture. In addition, the one-step meso-diaminopimelate dehydrogenase pathway does not limit lysine flux in Corynebacterium under these conditions.