Characterization of the dicarboxylate transporter DctA in Corynebacterium glutamicum.
Transporters of the dicarboxylate amino acid-cation symporter family often mediate uptake of C(4)-dicarboxylates, such as succinate or l-malate, in bacteria. A member of this family, dicarboxylate transporter A (DctA) from Corynebacterium glutamicum, was characterized to catalyze uptake of the C(4)-dicarboxylates succinate, fumarate, and l-malate, which was inhibited by oxaloacetate, 2-oxoglutarate, and glyoxylate. DctA activity was not affected by sodium availability but was dependent on the electrochemical proton potential. Efficient growth of C. glutamicum in minimal medium with succinate, fumarate, or l-malate as the sole carbon source required high dctA expression levels due either to a promoter-up mutation identified in a spontaneous mutant or to ectopic overexpression. Mutant analysis indicated that DctA and DccT, a C(4)-dicarboxylate divalent anion/sodium symporter-type transporter, are the only transporters for succinate, fumarate, and l-malate in C. glutamicum.
Youn
Jung-Won
JW
Institute of Molecular Microbiology and Biotechnology, Westfalian Wilhelms University Muenster, D-48149 Muenster, Germany.
Jolkver
Elena
E
Krämer
Reinhard
R
Marin
Kay
K
Wendisch
Volker F
VF
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D048230:Corynebacterium glutamicum / Q000235:genetics / Q000378:metabolism*; D029382:Dicarboxylic Acid Transporters / Q000235:genetics / Q000378:metabolism*; D005650:Fumarates / Q000378:metabolism; D017353:Gene Deletion; D005816:Genetic Complementation Test; D008293:Malates / Q000378:metabolism; D008969:Molecular Sequence Data; D017354:Point Mutation; D019802:Succinic Acid / Q000378:metabolism
D001426:Bacterial Proteins; D029382:Dicarboxylic Acid Transporters; D005650:Fumarates; D008293:Malates; C030298:malic acid; D019802:Succinic Acid