Succinate Metabolism in Rhizobium Meliloti

During symbiosis, Rhizobium requires an energy source from the plant host to perform the energetically expensive nitrogen fixation process. C4-dicarboxylic acids, present at high levels in the nodule, appear to be the primary energy source supplied to the N2-fixing bacteroids by the plant (Ronson et al. 1981; Finan et al. 1983; Dilworth, Glenn 1984; Vance, Heichel 1991; Day, Copeland 1991). However, relatively little information is available on C4-dicarboxylic acid metabolism in Rhizobium bacteroids.