title: Morphological and genetic characterization of group I Clostridium botulinum type B strain 111 and the transcriptional regulator spoIIID gene knockout mutant in sporulation.
abstract: Clostridium botulinum is a heat-resistant spore-forming bacterium that causes the serious paralytic illness botulism. Heat-resistant spores may cause food sanitation hazards and sporulation plays a central role in the survival of C. botulinum. We observed morphological changes and investigated the role of the transcriptional regulator SpoIIID in the sporulation of C. botulinum type B strain 111 in order to elucidate the molecular mechanism in C. botulinum. C. botulinum type B formed heat-resistant spores through successive morphological changes corresponding to those of Bacillus subtilis, a spore-forming model organism. An analysis of the spoIIID gene knockout mutant revealed that the transcriptional regulator SpoIIID contributed to heat-resistant spore formation by C. botulinum type B and activated the transcription of the sigK gene later during sporulation. Transcription of the spoIIID gene, which differed from that in B. subtilis and Clostridium difficile, was observed in the sigE gene knockout mutant of C. botulinum type B. An analysis of the sigF gene knockout mutant showed that the sporulation-specific sigma factor SigF was essential for transcription of the spoIIID gene in C. botulinum type B. These results suggest that the regulation of sporulation in C. botulinum is not similar to that in B. subtilis and other clostridia.
authors: Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan.
authors: Koji
authors: K
authors: Hosomi
authors: Faculty of Pharmaceutical Sciences, Setsunan University, Hirakata, Osaka, Japan.
authors: Ritsuko
authors: R
authors: Kuwana
authors: Faculty of Pharmaceutical Sciences, Setsunan University, Hirakata, Osaka, Japan.
authors: Hiromu
authors: H
authors: Takamatsu
authors: Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan.
authors: Tomoko
authors: T
authors: Kohda
authors: Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan.
authors: Shunji
authors: S
authors: Kozaki
authors: Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan. Electronic address: mukamoto@vet.osakafu-u.ac.jp.
authors: Masafumi
authors: M
authors: Mukamoto
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D047014:Clostridium botulinum type B / Q000145:classification / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D055786:Gene Knockout Techniques; D023061:Gene Order; D018390:Gene Targeting; D008954:Models, Biological; D009154:Mutation; D010641:Phenotype; D013171:Spores, Bacterial; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D014157:Transcription Factors
keywords: Clostridium botulinum; Sporulation; Transcriptional regulator spoIIID