Abstract
Isolated cell walls of Clostridium botulinum type A strain 190L released an autolysin during autolysis of the cell walls. The autolysin was isolated from the cell walls, and partially purified 18.6-fold by ammonium sulfate precipitation, chromatography on DEAE-cellulose and gel filtration through Sephadex G-100. The purified preparation of the autolysin showed 2 major and 2 minor protein bands on polyacrylamide gel electro-phoresis. Some properties of the autolysin were examined using SDS-treated cell walls of the organisms as a substrate. The autolysin was active over a pH range of 6 to 8, with a maximum near pH 6.8. The lytic activity was stimulated by 10-4M each of Co++, Mg++ and Ca++ in the order, whereas it was inhibited markedly by Cu++. Mercaptoethanol (10-4-10-3M) significantly activated the lytic action. Trypsin and nagarse (10μg/ml) also stimulated the lytic activity. The lytic spectrum of the autolysin toward the SDS-treated cell walls obtained from various types of C. botulinum and C. per-fringens indicated a relatively high specificity. After treatment with hot formamide the cell walls of C. botulinum increased in susceptibility to the autolysin.
