title: Role of a type IV-like secretion system of Streptococcus suis 2 in the development of streptococcal toxic shock syndrome.
abstract: Streptococcus suis serotype 2 (S. suis 2) has evolved into a highly invasive pathogen that was found to be the cause of 2 large-scale outbreaks of streptococcus toxic shock syndrome (STSS) in China. However, the mechanism of action of this non-group A streptococcal (GAS) S. suis-caused STSS is still unknown. Previously, we identified a unique pathogenicity island (PAI) designated 89K that is specific to the STSS-causing epidemic strains of S. suis 2. In this study, we further report a functional type IV-like secretion system (T4SS-like system) harbored in the 89K PAI that contributes to the development of STSS. Knockout of the 2 key components (VirD4-89K and VirB4-89K) of the T4SS-like system eliminated the lethality of the highly virulent strain and impaired its ability to trigger host immune response in experimental infection of mice. Our findings provide a new insight into the pathogenesis of STSS caused by the highly pathogenic S. suis 2 isolates.
authors.affiliation: Department of Microbiology, Third Military Medical University, Chongqing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.forename: Gaoke
authors.initials: G
authors.lastname: Liu
authors.forename: Shu
authors.initials: S
authors.lastname: Li
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Song
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Tang
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Fuquan
authors.initials: F
authors.lastname: Hu
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D002681:China; D016207:Cytokines / Q000097:blood; D004195:Disease Models, Animal; D055786:Gene Knockout Techniques; D044404:Genomic Islands; D006651:Histocytochemistry; D006801:Humans; D008099:Liver / Q000473:pathology; D026901:Membrane Transport Proteins / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D012772:Shock, Septic / Q000382:microbiology*; D013290:Streptococcal Infections / Q000382:microbiology*; D017011:Streptococcus suis / Q000472:pathogenicity*; D016019:Survival Analysis; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D016207:Cytokines; D026901:Membrane Transport Proteins