title: Characterization of a toxin-deficient Clostridium perfringens strain, KZ1340.
abstract: Clostridium perfringens KZ1340, previously classified as Clostridium plagarum, is an isolate from Antarctic soil, and was identified as an alpha-, theta-, and kappa-toxin non-producing variant. On Southern hybridization, the variant was found to be defective in the pfoA (theta-toxin) gene, but the plc (alpha-toxin) and colA (kappa-toxin) genes were present on the same EcoRI fragment as in the standard strain, NCTC8237. Northern analysis revealed that mature plc mRNA was transcribed in KZ1340 though less efficiently than in NCTC8237, while no mature colA mRNA was present in KZ1340. After transformation of the pfoA and plc genes into the KZ1340 via shuttle vector, pJIR418, the pfoA gene was successfully expressed but the plc gene was not efficiently expressed, suggesting that in KZ1340 there is negative regulation of plc gene expression. Toxin-deficient C. perfringens KZ1340 might be a suitable host for expression analysis of the pfoA gene and other clostridial virulence genes, if expressed efficiently, because it produces a small amount of extracellular toxins.
authors.affiliation: Department of Microbiology, University of Tsukuba, Ibarak, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Shimizu
authors.forename: K
authors.initials: K
authors.lastname: Ohtani
authors.forename: W
authors.initials: W
authors.lastname: Ba-Thein
authors.forename: S
authors.initials: S
authors.lastname: Inui
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
authors.forename: H
authors.initials: H
authors.lastname: Hayashi
mesh_terms: D001427:Bacterial Toxins / Q000235:genetics* / Q000378:metabolism; D002135:Calcium-Binding Proteins; D003016:Clostridium perfringens / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D005798:Genes, Bacterial; D006460:Hemolysin Proteins; D003012:Microbial Collagenase / Q000235:genetics* / Q000378:metabolism; D010957:Plasmids; D014158:Transcription, Genetic; D014170:Transformation, Genetic; D010738:Type C Phospholipases
chemical_list: D001427:Bacterial Toxins; D002135:Calcium-Binding Proteins; D006460:Hemolysin Proteins; C020452:Clostridium perfringens theta-toxin; D010738:Type C Phospholipases; C040649:alpha toxin, Clostridium perfringens; D003012:Microbial Collagenase