@article{mbs:/content/journal/micro/10.1099/00221287-135-7-2055, author = "Mukasa, Hidehiko and Shimamura, Atsunari and Tsumori, Hideaki", title = "Purification and Characterization of Cell-associated Glucosyltransferase Synthesizing Insoluble Glucan from Streptococcus mutans Serotype c", journal= "Microbiology", year = "1989", volume = "135", number = "7", pages = "2055-2063", doi = "https://doi.org/10.1099/00221287-135-7-2055", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-135-7-2055", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = " Streptococcus mutans Ingbritt (serotype c) was shown to have a significant amount of cell-associated glucosyltransferase activity which synthesizes water-insoluble glucan from sucrose. The enzyme was extracted from the washed cells with SDS, renatured with Triton X-100, adsorbed to 1,3-α-d-glucan gel, and then eluted with SDS. The enzyme preparation was electrophoretically homogeneous, and the specific activity was 7·3 i.u. (mg protein)-1. The enzyme had an M r of 158000 as determined by SDS-PAGE, and was a strongly hydrophilic protein, as judged by its amino acid composition. The enzyme gradually aggregated in the absence of SDS. The enzyme had an optimum pH of 6·5 and a K m value of 16·3 mm for sucrose. Activity was stimulated 1·7-fold by dextran T10, but was not stimulated by high concentrations of ammonium sulphate. Below a sodium phosphate buffer concentration of 50 mm, activity was reduced by 75 %. This enzyme synthesized an insoluble d-glucan consisting of 76 mol % 1,3-α-linked glucose and 24 mol % 1,6-α-linked glucose.", }