Abstract
Multiple forms of dextransucrase were demonstrated by using six subclass strains of Leuconostoc mesenteroides, NRRL B-512F, B-1298, B-1307, B-1355, B-1375, and B-1416. Gel filtration of the dextrans produced at the early stages of culture showed a bimodal distribution of the molecular weight. The total enzyme activity produced amounted to 8.3-32.2 units per 100ml culture among the strains. Partially purified enzyme preparations from six strains gave an intrinsic multiple pattern being resolved into more than two activities on polyacrylamide gel electrophoresis. Judging from the susceptibility to the two different dextranases, types and contents of the secondary linkages in the dextrans synthesized by these enzymes might correspond to the respective native dextrans. In contrast to a linear progress curve for dextran synthesis with the enzymes from B-512F and B-1375 strains, those from B-1298 and B-1416 gave a characteristic sigmoidal curve for the polymerizing (transferase) reaction.
