title: iTRAQ-based quantitative proteomic analysis reveals potential virulence factors of Erysipelothrix rhusiopathiae.
abstract: Erysipelothrix rhusiopathiae is a ubiquitous pathogen that has caused considerable economic losses to pig farmers. However, the mechanisms of E. rhusiopathiae pathogenesis remain unclear. To identify new virulence-associated factors, the differentially abundant cell wall-associated proteins (CWPs) between high- and low-virulence strains were investigated through isobaric Tags for Relative and Absolute Quantitation (iTRAQ) combined with liquid chromatography-quadrupole mass spectrometry (LC-MS/MS). In total, 100 CWPs showed significant differences in abundance. Selected differences were verified by western blotting to support the iTRAQ data. Among the differential proteins, the proteins with higher abundance in the high-virulence strain were mostly ABC transporter proteins and adhesion proteins, and the proteins with lower abundance in the high-virulence strain were mainly stress-response proteins. The more abundant proteins in the high-virulence strain may be related to bacterial virulence. The iTRAQ results showed that the abundance of the sugar ABC transporter substrate-binding protein Sbp (No. 5) was higher by 1.73-fold. We further constructed an sbp-deletion mutant. Experiments in animal models showed that the sbp-deletion mutant caused decreased mortality. Together, our data indicated that transporter proteins and adhesion proteins may play important roles in E. rhusiopathiae virulence and confirmed that sbp contributed to the virulence of E. rhusiopathiae.
  
  
  
  To our knowledge, this is the first proteomic analysis comparing differentially abundant CWPs between high- and low-virulence E. rhusiopathiae strains by iTRAQ. We generated comprehensive and accurate lists of E. rhusiopathiae CWPs proteomes and identified many differences at the protein level. Among the differential proteins with higher abundance in the high-virulence strain, sbp was verified to contribute to the virulence of E. rhusiopathiae through the construction of an sbp-deletion mutant. The differential proteins with higher abundance in the high-virulence strain identified in the present study should provide a foundation for future evaluation of virulence factors.
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Jingtao
authors.initials: J
authors.lastname: Li
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Anding
authors.initials: A
authors.lastname: Zhang
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Zhongmin
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Shuxian
authors.initials: S
authors.lastname: Yan
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Sun
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.
authors.forename: Huanchun
authors.initials: H
authors.lastname: Chen
authors.affiliation: Animal Infectious Disease Unit, National State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China; College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture, Wuhan, China; Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China. Electronic address: jinmeilin@mail.hzau.edu.cn.
authors.forename: Meilin
authors.initials: M
authors.lastname: Jin
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000032:analysis / Q000378:metabolism; D018829:Adhesins, Bacterial / Q000032:analysis / Q000378:metabolism; D000818:Animals; D001426:Bacterial Proteins / Q000032:analysis; D002853:Chromatography, Liquid; D004888:Erysipelothrix / Q000472:pathogenicity*; D050505:Mutant Proteins / Q000235:genetics / Q000494:pharmacology; D040901:Proteomics / Q000379:methods*; D013552:Swine / Q000382:microbiology; D053719:Tandem Mass Spectrometry; D037521:Virulence Factors / Q000032:analysis*
chemical_list: D018528:ATP-Binding Cassette Transporters; D018829:Adhesins, Bacterial; D001426:Bacterial Proteins; D050505:Mutant Proteins; D037521:Virulence Factors
keywords: Cell wall proteins; Comparative proteomics; Erysipelothrix rhusiopathiae; Virulence factor