title: Identification of first exfoliative toxin in Staphylococcus pseudintermedius.
abstract: Staphylococcus aureus, Staphylococcus hyicus, and Staphylococcus chromogenes are known to cause skin infections in human or animals by producing exfoliative toxins (ETs). Staphylococcus pseudintermedius can also cause canine pyoderma, but no exfoliative toxins or similar toxins have been reported. PCR with degenerate primers targeted to the conserved regions in ETA, ETB, and ETD from S. aureus and SHETB from S. hyicus, and subsequent chromosome walking identified a novel gene, designated as exi (exfoliative toxin of pseudintermedius) in S. pseudintermedius. EXI had significant homologies with the exfoliative toxins (43-68% identity), particularly with ETB (67.1%), ETD (67.9%), and SHETB (65.1%). Phylogenetic analysis showed close relation between EXI and ETB with a bootstrap value of 80%. Neonatal mice injected with the crude proteins from the culture supernatant or recombinant EXI showed gross blisters and/or characteristic skin exfoliation. The prevalence of exi assessed by dot-blot hybridization was 23.3% (10/43) in S. pseudintermedius isolates from canine pyoderma. The EXI reported herein is the first exfoliative toxin identified in S. pseudintermedius.
authors.affiliation: Department of Animal Health 2, School of Veterinary Medicine, Azabu University, Kanagawa, Japan. saitohk@azabu-u.ac.jp
authors.forename: Keiko
authors.initials: K
authors.lastname: Futagawa-Saito
authors.forename: Shinichiroh
authors.initials: S
authors.lastname: Makino
authors.forename: Fujiko
authors.initials: F
authors.lastname: Sunaga
authors.forename: Yukio
authors.initials: Y
authors.lastname: Kato
authors.forename: Naomi
authors.initials: N
authors.lastname: Sakurai-Komada
authors.forename: William
authors.initials: W
authors.lastname: Ba-Thein
authors.forename: Tsuguaki
authors.initials: T
authors.lastname: Fukuyasu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001427:Bacterial Toxins / Q000235:genetics* / Q000633:toxicity*; D016000:Cluster Analysis; D017931:DNA Primers / Q000235:genetics; D004195:Disease Models, Animal; D004283:Dog Diseases / Q000382:microbiology*; D004285:Dogs; D005083:Exfoliatins / Q000235:genetics* / Q000633:toxicity*; D051379:Mice; D008969:Molecular Sequence Data; D010802:Phylogeny; D011041:Poisoning; D016133:Polymerase Chain Reaction / Q000379:methods; D011711:Pyoderma / Q000382:microbiology / Q000662:veterinary*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013210:Staphylococcus / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D001427:Bacterial Toxins; D017931:DNA Primers; D005083:Exfoliatins