Transport of amino acids by strains of Sinorhizobium meliloti.

All strains were grown in M9 modified glucose/NH4Cl minimal medium. Rates of uptake are expressed as nmol min−1mg−1 protein. Values are the mean ± SEM of determinations from three independent cultures, except for strain 2011 alanine, leucine and valine transports, which just served as controls and represent single measurements. ND = not determined.