No abstract

Aims: To identify and characterize amino acid transport in Leuconostoc mesenteroides. Methods and Results: The transport of labelled amino acids was measured in whole cells of Leuc. mesenteroides CNRZ 1273. Systems were operative under physiological conditions of growth, energy dependent and differed from peptide transport. Some of the systems were shared by several amino acids. Kinetic analysis indicated the presence of three transport systems with very high (VH), high (H) and low affinity (H) for the 11 amino acids studied. The K t values (lmol l )1 ) ranged from 0AE088 to 0AE815 (VH), 6-390 (H) and 320-4500 (L) and the V max values [nmol s )1 (g dry weight))1 ] from 0AE015 to 0AE8 (VH), 15-95 (H) and 90-470 (L). Conclusions:The study showed the presence of three transport systems in Leuc. mesenteroides for all amino acids tested, some of them being shared by several amino acids. Significance and Impact of the Study. The findings are discussed with reference to the growth of Leuc. mesenteroides in milk as pure or in mixed-strain culture with Lactococcus lactis.