title: Identification of a novel locus that regulates expression of toxin genes in Clostridium perfringens.
abstract: A novel gene that regulates the alpha-toxin (plc), kappa-toxin (colA), and theta;-toxin (pfoA) genes was identified using toxin-negative mutant strains of Clostridium perfringens. The cloned 3.2-kb fragment contained the virX gene encoding a 51-amino acid polypeptide of unknown function that seemed to be responsible for the activation of toxin genes. The virX knock out mutant of wild-type strain 13 showed a reduced expression of the plc, colA, and pfoA genes, which was complemented by the transformation of the intact virX gene. Deletion and site-directed mutagenesis studies suggested that the virX gene acts as a regulatory RNA rather than as a peptide regulator. The virX locus found in this study might play a part in the signal transduction to regulate toxin production in C. perfringens.
authors: Department of Infection Biology, Department of Microbiology, Institute of Basic Medical Sciences, University of Tsukuba, 1-1-1, Tennohdai, Ibaraki 305-8575, Japan.
authors: Kaori
authors: K
authors: Ohtani
authors: Sushanta K
authors: SK
authors: Bhowmik
authors: Hideo
authors: H
authors: Hayashi
authors: Tohru
authors: T
authors: Shimizu
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000502:physiology; D001427:Bacterial Toxins / Q000096:biosynthesis* / Q000235:genetics; D001483:Base Sequence; D002135:Calcium-Binding Proteins; D003016:Clostridium perfringens / Q000235:genetics* / Q000378:metabolism; D018389:Codon, Nonsense; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D006460:Hemolysin Proteins; D003012:Microbial Collagenase / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D012329:RNA, Bacterial / Q000235:genetics* / Q000502:physiology; D015398:Signal Transduction; D010738:Type C Phospholipases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D002135:Calcium-Binding Proteins; D018389:Codon, Nonsense; D006460:Hemolysin Proteins; D012329:RNA, Bacterial; C020452:Clostridium perfringens theta-toxin; D010738:Type C Phospholipases; C040649:alpha toxin, Clostridium perfringens; D003012:Microbial Collagenase; C460361:kappa-toxin, Clostridium perfringens