title: Mode of action of a germination-specific cortex-lytic enzyme, SleC, of Clostridium perfringens S40.
abstract: The hydrolysis of the bacterial spore peptidoglycan (cortex) is a crucial event in spore germination. It has been suggested that SleC and SleM, which are conserved among clostridia, are to be considered putative cortex-lytic enzymes in Clostridium perfringens. However, little is known about the details of the hydrolytic process by these enzymes during germination, except that SleM functions as a muramidase. Muropeptides derived from SleC-digested decoated spores of a Bacillus subtilis mutant that lacks the enzymes, SleB, YaaH and CwlJ, related to cortex hydrolysis were identified by amino acid analysis and mass spectrometry. The results suggest that SleC is most likely a bifunctional enzyme possessing lytic transglycosylase activity and N-acetylmuramoyl-L-alanine amidase activity confined to cross-linked tetrapeptide-tetrapeptide moieties of the cortex structure. Furthermore, it appears that during germination of Clostridium perfringens spores, SleC causes merely small and local changes in the cortex structure, which are necessary before SleM can function.
authors.affiliation: Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Kumazawa
authors.forename: Atsushi
authors.initials: A
authors.lastname: Masayama
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fukuoka
authors.forename: Shio
authors.initials: S
authors.lastname: Makino
authors.forename: Tohru
authors.initials: T
authors.lastname: Yoshimura
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Moriyama
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001412:Bacillus subtilis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D003016:Clostridium perfringens / Q000201:enzymology*; D003432:Cross-Linking Reagents / Q000737:chemistry; D006867:Hydrolases / Q000378:metabolism; D006868:Hydrolysis; D015151:Immunoblotting; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009113:Muramidase / Q000378:metabolism; D010455:Peptides / Q000737:chemistry; D010457:Peptidoglycan / Q000737:chemistry / Q000378:metabolism*; D046928:Peptidoglycan Glycosyltransferase / Q000378:metabolism*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013056:Spectrophotometry, Ultraviolet; D013171:Spores, Bacterial / Q000201:enzymology*
chemical_list: D000596:Amino Acids; D003432:Cross-Linking Reagents; D010455:Peptides; D010457:Peptidoglycan; D046928:Peptidoglycan Glycosyltransferase; D006867:Hydrolases; D009113:Muramidase