title: Cloning, expression, and characterization of the superantigen streptococcal pyrogenic exotoxin G from Streptococcus dysgalactiae.
abstract: We identified seven novel variants of streptococcal pyrogenic exotoxin G (SPEGG), a superantigen, in Streptococcus dysgalactiae subsp. dysgalactiae or equisimilis isolates from clinical cases of infection in humans and animals. Phylogenetic analysis of the SPEGG variants indicated two clades in the dendrogram: one composed of variants derived from the bacteria isolated from the humans and the other composed of variants from the bacteria isolated from the animals. Bovine peripheral blood mononuclear cells (PBMCs) were stimulated effectively by recombinant SPEGGs (rSPEGGs) expressed in Escherichia coli, while human PBMCs were not stimulated well by any of the rSPEGGs tested. SPEGGs selectively stimulated bovine T cells bearing Vbeta1,10 and Vbeta4. Bovine serum showed reactivity to the rSPEGG proteins. These results indicated that SPEGGs have properties as superantigens, and it is likely that SPEGGs play a pathogenic role in animals.
authors.affiliation: Department of Infectious Diseases, Research Institute, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan.
authors.forename: Jizi
authors.initials: J
authors.lastname: Zhao
authors.forename: Tomohito
authors.initials: T
authors.lastname: Hayashi
authors.forename: Susanna
authors.initials: S
authors.lastname: Saarinen
authors.forename: Anastassios C
authors.initials: AC
authors.lastname: Papageorgiou
authors.forename: Hidehito
authors.initials: H
authors.lastname: Kato
authors.forename: Ken'ichi
authors.initials: K
authors.lastname: Imanishi
authors.forename: Teruo
authors.initials: T
authors.lastname: Kirikae
authors.forename: Ryo
authors.initials: R
authors.lastname: Abe
authors.forename: Takehiko
authors.initials: T
authors.lastname: Uchiyama
authors.forename: Tohru
authors.initials: T
authors.lastname: Miyoshi-Akiyama
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005098:Exotoxins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D015870:Gene Expression; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets / Q000276:immunology; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013290:Streptococcal Infections / Q000382:microbiology / Q000662:veterinary; D013291:Streptococcus / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D018089:Superantigens / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D005098:Exotoxins; D018089:Superantigens; C027951:erythrogenic toxin