title: Sequence variation in the alpha-toxin encoding plc gene of Clostridium perfringens strains isolated from diseased and healthy chickens.
abstract: The aim of the present study was to analyse the genetic diversity of the alpha-toxin encoding plc gene and the variation in alpha-toxin production of Clostridium perfringens type A strains isolated from presumably healthy chickens and chickens suffering from either necrotic enteritis (NE) or cholangio-hepatitis. The alpha-toxin encoding plc genes from 60 different pulsed-field gel electrophoresis (PFGE) types (strains) of C. perfringens were sequenced and translated in silico to amino acid sequences and the alpha-toxin production was investigated in batch cultures of 45 of the strains using an enzyme-linked immunosorbent assay (ELISA) approach. Overall, the truncated amino acid sequences showed close similarity (>98% at the amino acid level) to previously reported sequences from chicken-derived C. perfringens isolates. Variations were however observed in 23 out of 379 aa positions leading to the definition of 26 different alpha-toxin sequence types among the 60 strains. Moreover, a type II intron of 834 non-coding nucleotides was identified in the plc gene of three of the investigated strains. The in vitro alpha-toxin production investigated in 45 of the strains, including the three harbouring the intron, revealed no correlation between PFGE type, alpha-toxin sequence type, health status of the host chickens and level of alpha-toxin production. It is therefore concluded that neither plc gene type nor alpha-toxin production level seems to correlate to origin (healthy or diseased chicken) of the C. perfringens strains.
authors.affiliation: Institute of Animal Health, Welfare and Nutrition, Faculty of Agricultural Sciences, University of Aarhus, DK-8830 Tjele, Denmark.
authors.forename: Lone
authors.initials: L
authors.lastname: Abildgaard
authors.forename: Ricarda M
authors.initials: RM
authors.lastname: Engberg
authors.forename: Karl
authors.initials: K
authors.lastname: Pedersen
authors.forename: Andreas
authors.initials: A
authors.lastname: Schramm
authors.forename: Ole
authors.initials: O
authors.lastname: Hojberg
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001427:Bacterial Toxins / Q000235:genetics*; D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000235:genetics*; D002645:Chickens; D003015:Clostridium Infections / Q000382:microbiology / Q000662:veterinary*; D003016:Clostridium perfringens / Q000235:genetics* / Q000302:isolation & purification; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005798:Genes, Bacterial; D014644:Genetic Variation; D008969:Molecular Sequence Data; D011201:Poultry Diseases / Q000382:microbiology*; D012329:RNA, Bacterial / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D010738:Type C Phospholipases / Q000235:genetics*
chemical_list: D001427:Bacterial Toxins; D002135:Calcium-Binding Proteins; D012329:RNA, Bacterial; D010738:Type C Phospholipases; C040649:alpha toxin, Clostridium perfringens