Identification of a Novel Virulence-Related Gene in Streptococcus suis Type 2 Strains

• Published in: Current microbiology Vol. 61; no. 6; pp. 494 - 499
• Main Authors: Zhang, Hui, Fan, Hongjie, Lu, Chenping
• Format: Journal Article
• Language: English
• Published: New York Springer-Verlag 01.12.2010; Springer Nature B.V
• Subjects: Animal diseases; Animals; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Biomedical and Life Sciences; Biotechnology; Blotting, Southern; Danio rerio; Disease Models, Animal; Gene Expression; Gene Knockout Techniques; Gene Library; Genetic recombination; Life Sciences; Microbiology; Mutagenesis, Insertional; Mutation; Polymerase Chain Reaction; Streptococcal Infections - microbiology; Streptococcal Infections - pathology; Streptococcal Infections - veterinary; Streptococcus infections; Streptococcus suis; Streptococcus suis - genetics; Streptococcus suis - isolation & purification; Streptococcus suis - pathogenicity; Swine; Virulence; Virulence Factors - genetics; Virulence Factors - metabolism; Zebrafish; Homologous Recombination; Spectinomycin; Avirulent Strain; Luria Broth; Southern Hybridization Analysis
• ISSN: 0343-8651; 1432-0991
• DOI: 10.1007/s00284-010-9643-0

The trag is a novel infection-related factor identified using in vivo-induced antigen technology (IVIAT) from SS2 expression libraries with swine convalescent sera. PCR-based studies of various S. suis strains collected from different sources revealed that the trag gene was present in all the virulent SS2 strains, but absent in the avirulent T15 strain. PCR and Southern hybridization analyses of a trag -knockout strain created through homologous recombination confirmed the coding sequence of trag replaced by spc R cassette in the ∆ trag mutant. Zebrafish was used to identify the role of trag in SS2 virulence. The reduction of virulence in the trag mutant compared to the wild-type in animal model systems, laid the foundation for further studies.