title: Ketopantoate reductase activity is only encoded by ilvC in Corynebacterium glutamicum.
abstract: Ketopantoate reductase catalyzes the second step of the pantothenate pathway after ketoisovalerate, common intermediate in valine, leucine and pantothenate biosynthesis. We show here that the Corynebacterium glutamicum ilvC gene is able to complement a ketopantoate reductase deficient Escherichia coli mutant. Thus ilvC, encoding acetohydroxyacid isomeroreductase, involved in the common pathway for branched-chained amino acids, also exhibits ketopantoate reductase activity. Enzymatic activity was confirmed by biochemical analysis in C. glutamicum. Furthermore, inactivation of ilvC in C. glutamicum leads to auxotrophy for pantothenate, indicating that ilvC is the only ketopantoate reductase- encoding gene in C. glutamicum.
authors.affiliation: Institut de Génétique et Microbiologie, Bat 360, Université Paris-Sud, Centre d'Orsay, F-91405 Orsay cedex, France.
authors.forename: Muriel
authors.initials: M
authors.lastname: Merkamm
authors.forename: Christophe
authors.initials: C
authors.lastname: Chassagnole
authors.forename: Nic D
authors.initials: ND
authors.lastname: Lindley
authors.forename: Armel
authors.initials: A
authors.lastname: Guyonvarch
mesh_terms: D000429:Alcohol Oxidoreductases / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*; D000597:Amino Acids, Branched-Chain / Q000096:biosynthesis* / Q000235:genetics; D003067:Coenzymes / Q000235:genetics / Q000378:metabolism; D003352:Corynebacterium / Q000201:enzymology* / Q000235:genetics*; D004789:Enzyme Activation; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D005816:Genetic Complementation Test; D050540:Ketol-Acid Reductoisomerase; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D000597:Amino Acids, Branched-Chain; D003067:Coenzymes; D011994:Recombinant Proteins; D000429:Alcohol Oxidoreductases; C021934:2-dehydropantoate 2-reductase; D050540:Ketol-Acid Reductoisomerase