title: Characterization of the spore surface and exosporium proteins of Clostridium sporogenes; implications for Clostridium botulinum group I strains.
abstract: Clostridium sporogenes is a non-pathogenic close relative and surrogate for Group I (proteolytic) neurotoxin-producing Clostridium botulinum strains. The exosporium, the sac-like outermost layer of spores of these species, is likely to contribute to adhesion, dissemination, and virulence. A paracrystalline array, hairy nap, and several appendages were detected in the exosporium of C. sporogenes strain NCIMB 701792 by EM and AFM. The protein composition of purified exosporium was explored by LC-MS/MS of tryptic peptides from major individual SDS-PAGE-separated protein bands, and from bulk exosporium. Two high molecular weight protein bands both contained the same protein with a collagen-like repeat domain, the probable constituent of the hairy nap, as well as cysteine-rich proteins CsxA and CsxB. A third cysteine-rich protein (CsxC) was also identified. These three proteins are also encoded in C. botulinum Prevot 594, and homologues (75-100% amino acid identity) are encoded in many other Group I strains. This work provides the first insight into the likely composition and organization of the exosporium of Group I C. botulinum spores.
authors.affiliation: Krebs Institute, University of Sheffield, Sheffield S10 2TN, UK; Dept. of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
authors.forename: Thamarai K
authors.initials: TK
authors.lastname: Janganan
authors.affiliation: Krebs Institute, University of Sheffield, Sheffield S10 2TN, UK; Dept. of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK.
authors.forename: Nic
authors.initials: N
authors.lastname: Mullin
authors.affiliation: Krebs Institute, University of Sheffield, Sheffield S10 2TN, UK; Dept. of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
authors.forename: Svetomir B
authors.initials: SB
authors.lastname: Tzokov
authors.affiliation: Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK.
authors.forename: Sandra
authors.initials: S
authors.lastname: Stringer
authors.affiliation: Krebs Institute, University of Sheffield, Sheffield S10 2TN, UK; Dept. of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Fagan
authors.affiliation: Krebs Institute, University of Sheffield, Sheffield S10 2TN, UK; Dept. of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK.
authors.forename: Jamie K
authors.initials: JK
authors.lastname: Hobbs
authors.affiliation: Dept. of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK.
authors.forename: Anne
authors.initials: A
authors.lastname: Moir
authors.affiliation: Krebs Institute, University of Sheffield, Sheffield S10 2TN, UK; Dept. of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK. Electronic address: p.bullough@sheffield.ac.uk.
authors.forename: Per A
authors.initials: PA
authors.lastname: Bullough
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D003013:Clostridium / Q000737:chemistry*; D003014:Clostridium botulinum / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D017386:Sequence Homology, Amino Acid; D013171:Spores, Bacterial / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins
keywords: Cysteine rich proteins; Spore appendages; Two dimensional crystals