A monocarboxylate permease of Rhizobium leguminosarum is the first member of a new subfamily of transporters.

ABSTRACT: Amino acid transport by Rhizobium leguminosarum is dominated by two ABC transporters, the general amino acid permease (Aap) and the branched-chain amino acid permease (Bra). However, mutation of these transporters does not prevent this organism from utilizing alanine for growth. An R. leguminosarum permease (MctP) has been identified which is required for optimal growth on alanine as a sole carbon and nitrogen source. Characterization of MctP confirmed that it transports alanine (K(m) = 0.56 mM) and other monocarboxylates such as lactate and pyruvate (K(m) = 4.4 and 3.8 micro M, respectively). Uptake inhibition studies indicate that propionate, butyrate, alpha-hydroxybutyrate, and acetate are also transported by MctP, with the apparent affinity for solutes demonstrating a preference for C3

SUBMITTER: Hosie AH 

PROVIDER: S-EPMC135354 | biostudies-literature | 2002 Oct

REPOSITORIES: biostudies-literature