title: Prevalent distribution and conservation of Streptococcus suis Lmb protein and its protective capacity against the Chinese highly virulent strain infection.
abstract: Streptococcus suis (S. suis) is an important zoonotic pathogen that causes multiple diseases in both pigs and humans. Many studies suggest that Streptococcus utilizes host extracellular matrix proteins, including laminin, for adhesion and invasion of host cells. Recently, we identified a putative Lmb protein (CDS 0330) of a highly virulent strain of S. suis (serotype 2). In this study, we characterized the ability of CDS 0330 to bind human laminin, and evaluated the protective efficacy of a recombinant protein vaccine. Bioinformatic analysis revealed that both the amino acid sequence and tertiary structure of CDS 0330 were similar to Lmb proteins in other Streptococcus. In addition, the sequence of CDS 0330 was present in the genomes of 26 of the 38 sequenced streptococci species, indicating an early origin and conservation of this gene. Particularly, all 17 sequenced S. suis genomes, regardless of serotype or geographic origin, contained CDS 0330 gene in their genome with a minimum pair-wise amino acid identity of 92%. PCR amplification revealed that CDS 0330 gene is distributed throughout 35 S. suis serotypes in the lmb-htp format. Flow cytometry analysis confirmed that CDS 0330 was expressed on the cell surface of S. suis, and ELISA revealed the recombinant CDS 0330 protein could bind laminin in vitro. Finally, vaccinating mice with recombinant CDS 0330 protein significantly prolonged survival after S. suis infection. Together, these data reveal that CDS 0330 is a laminin binding protein of S. suis 2, and open new avenues for preventing S. suis 2 infection.
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu Province 210093, China; Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China.
authors.forename: Yan-Mei
authors.initials: YM
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu Province 210093, China; Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China; School of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China.
authors.forename: Zhu-Qing
authors.initials: ZQ
authors.lastname: Shao
authors.affiliation: Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China.
authors.forename: Xianfu
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China.
authors.forename: Changjun
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Tang
authors.affiliation: Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing 210002, China; School of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China. Electronic address: panxiuzhen_2004@163.com.
authors.forename: Xiuzhen
authors.initials: X
authors.lastname: Pan
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D002681:China; D017124:Conserved Sequence; D004195:Disease Models, Animal; D006801:Humans; D007797:Laminin / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D013290:Streptococcal Infections / Q000276:immunology / Q000517:prevention & control; D022541:Streptococcal Vaccines / Q000235:genetics / Q000276:immunology*; D017011:Streptococcus suis / Q000235:genetics / Q000276:immunology*; D016019:Survival Analysis; D013552:Swine; D014614:Vaccines, Synthetic / Q000235:genetics / Q000378:metabolism
chemical_list: D018829:Adhesins, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D007797:Laminin; D008565:Membrane Proteins; D022541:Streptococcal Vaccines; D014614:Vaccines, Synthetic
keywords: Lmb; Protective antigen; Streptococcus suis