Characterization of a new protective antigen of Streptococcus canis.
Streptococcus canis (S. canis), a lancefield group G streptococcus, is an opportunistic pathogen mainly found in dogs and cats. The study on pathogenesis and protective immune mechanism of S. canis is not clear. A new streptococcal protective antigen (SPA) was first identified from a genomic library of S. canis. SPA of S. canis (SPASc) contained a 1224-bp open reading frame which encoded a 407aa protein and a 34-aa signal sequence with a deduced molecular mass of 46.368 kDa. Protein analysis and BLAST result showed that SPASc was homologous to the SPA of Streptococcus. equi subsp. zooepidemicus, M protein Streptococcus. equi., and SPA of Streptococcus pyogenes. The protective response of SPASc antiserum was demonstrated by passive mouse protection. These studies suggested that SPASc might be an important component of vaccines to prevent S. canis infections.
Yang
Jiande
J
Department of Animal Science, Tianjin Agricultural University, Tianjin, 300384, China. jiande.yang@gmail.com
Liu
Yanfei
Y
Xu
Jun
J
Li
Benqiang
B
D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D001483:Base Sequence; D004285:Dogs; D004591:Electrophoresis, Polyacrylamide Gel; D007106:Immune Sera / Q000276:immunology; D015151:Immunoblotting; D051379:Mice; D008969:Molecular Sequence Data; D010802:Phylogeny; D013291:Streptococcus / Q000235:genetics / Q000276:immunology*
D000942:Antigens, Bacterial; D007106:Immune Sera; C119204:streptococcal protective antigen