[ODP-106] Degradation of the autolysin of Clostridium perfringens
Autolysin of Clostridium perfringens (Acp, CPE1231), a single polypeptide with a molecular weight of 122 kDa, is composed of 10 N-terminal cell wall binding domains and a C-terminal catalytic domain (CD) which exerts an N- acetylglucosaminidase activity. In previous study, the apparent molecular weight of Acp was reported to be 95 kDa. However, the presence of 122 kDa Acp as well as 95 kDa Acp was found by our Western blot analysis using anti-AcpCD polyclonal antibody. Here, we investigated the production of these Acps in the different stages of growth. Both 122 kDa and 95 kDa were detected during the logarithmic phase, whereas only 95 kDa Acp was detected during the stationary phase. These 122 kDa Acp and 95 kDa Acp showed lytic activity by renaturing SDS-PAGE containing Micrococcus luteus cells. The sequence of the 10 N-terminal amino acids of the purified 95 kDa Acp was determined. It was found that the N-terminal amino acid of 95 kDa Acp was the 297th serine of whole Acp polypeptide. These results suggested that 95 kDa Acp is the degradation product of 122 kDa Acp. Moreover, it was also found that both 122 kDa Acp and 95 kDa Acp were detected in the culture supernatant.