Identification and proteome analysis of the two-component VirR/VirS system in epidemic Streptococcus suis serotype 2.
Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen that infects pigs and sporadically causes serious infections in humans. Two recent large-scale outbreaks of human streptococcal toxic-shock-like syndrome with high mortality occurred in China, posing new challenges for global public health. However, the global regulation of the virulence of epidemic SS2 isolates lacks a systematic understanding. In this study, we performed a mutational and functional analysis of an SS2 two-component system that is orthologous to the VirR/VirS regulatory system of Clostridium perfringens. An isogenic knockout mutant of VirR/VirS (ΔvirRS) was found to exhibit marked phenotypic changes, including the formation of shorter chains and thinner capsular walls, more easily cleared in whole blood, and decreased oxidative stress tolerance. Furthermore, the ΔvirRS mutant was greatly attenuated in a mouse model. Comparative proteome analysis of the expression profiles of the wild-type strain with the ΔvirRS mutant allowed us to identify 72 proteins that are differentially expressed in the absence of the VirR/VirS system and that are directly responsible for the pleiotropic phenotype of the ΔvirRS mutant.
Department of Endocrinology, Southwest Hospital, Third Military Medical University, Chongqing, China.
Haihui
H
Wang
Xiaodong
X
Shen
Yan
Y
Zhao
Min
M
Wang
Qiu
Q
Zhong
Tian
T
Chen
Fuquan
F
Hu
Ming
M
Li
D000818:Animals; D058491:Bacterial Load; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall; D004195:Disease Models, Animal; D055786:Gene Knockout Techniques; D051379:Mice; D008807:Mice, Inbred BALB C; D050296:Microbial Viability; D018384:Oxidative Stress; D010641:Phenotype; D020543:Proteome / Q000032:analysis* / Q000378:metabolism; D018085:Regulon; D013290:Streptococcal Infections / Q000378:metabolism / Q000382:microbiology; D017011:Streptococcus suis / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D016019:Survival Analysis; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D020543:Proteome; D037521:Virulence Factors