title: Effect of the glycosyltransferases on the capsular polysaccharide synthesis of Streptococcus suis serotype 2.
abstract: Streptococcus suis serotype 2 (S. suis 2) is a serious zoonotic pathogen causing septicemia and meningitis in piglets and humans. The capsular polysaccharide (CPS) is an essential virulence factor for S. suis 2 to infect the host. The synthesis of CPS repeating units involves multiple glycosyltransferases. In this study, four genes (cps2E, cps2G, cps2J and cps2L) encoding different glycosyltransferases involved in CPS synthesis were researched in S. suis 2. Four deletion mutants (Δcps2E, Δcps2G, Δcps2J and Δcps2L) with their CPS incomplete and their sialic acid content significantly decreased were constructed in S. suis 2 SC19. All these four mutant strains showed enhanced adhesion to Hep-2 cells and increased sensitivity to phagocytosis. Flow cytometric analysis also revealed that these four mutants were more susceptible to the attack by the complement system. In a mouse model of infection, the mutant strains were rapidly cleared by the immune system, compared with the wild-type strain. In summary, this study characterized four genes (cps2E, cps2G, cps2J and cps2L) involved in CPS synthesis of S. suis 2 SC19 and it revealed that these genes were all crucial for SC19 to invade and survive in the host.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Ding
authors.affiliation: Center of Bio-Pesticide Engineering Research, Hubei Academy of Agricultural Science, Wuhan 430064, Hubei, China.
authors.forename: Manli
authors.initials: M
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
authors.forename: Xiaopei
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
authors.forename: Bingbing
authors.initials: B
authors.lastname: Zong
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
authors.forename: Xiangru
authors.initials: X
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
authors.forename: Huanchun
authors.initials: H
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
authors.forename: Weicheng
authors.initials: W
authors.lastname: Bei
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, Hubei, China. Electronic address: tanchen@mail.hzau.edu.cn.
authors.forename: Chen
authors.initials: C
authors.lastname: Tan
mesh_terms: D000818:Animals; D016667:Bacterial Capsules / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D045744:Cell Line, Tumor; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D005434:Flow Cytometry; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D005810:Multigene Family; D019158:N-Acetylneuraminic Acid / Q000096:biosynthesis; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000378:metabolism; D017384:Sequence Deletion; D013290:Streptococcal Infections / Q000382:microbiology; D017011:Streptococcus suis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D011135:Polysaccharides, Bacterial; D037521:Virulence Factors; D016695:Glycosyltransferases; D019158:N-Acetylneuraminic Acid
keywords: Capsular polysaccharide; S. suis 2 SC19; Streptococcus suis serotype 2; Virulence; cps2E/cps2G/cps2J/cps2L