title: Genotyping and investigating capsular polysaccharide synthesis gene loci of non-serotypeable Streptococcus suis isolated from diseased pigs in Canada.
abstract: Streptococcus suis (S. suis) is an important swine pathogen and an emerging zoonotic agent. Most clinical S. suis strains express capsular polysaccharides (CPS), which can be typed by antisera using the coagglutination test. In this study, 79 S. suis strains recovered from diseased pigs in Canada and which could not be typed using antisera were further characterized by capsular gene typing and sequencing. Four patterns of cps locus were observed: (1) fifteen strains were grouped into previously reported serotypes but presented several mutations in their cps loci, when compared to available data from reference strains; (2) seven strains presented a complete deletion of the cps locus, which would result in an inability to synthesize capsule; (3) forty-seven strains were classified in recently described novel cps loci (NCLs); and (4) ten strains carried novel NCLs not previously described. Different virulence gene profiles (based on the presence of mrp, epf, and/or sly) were observed in these non-serotypeable strains. This study provides further insight in understanding the genetic characteristics of cps loci in non-serotypeable S. suis strains recovered from diseased animals. When using a combination of the previously described 35 serotypes and the complete NCL system, the number of untypeable strains recovered from diseased animals in Canada would be significantly reduced.
authors.affiliation: State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China.
authors.forename: Han
authors.initials: H
authors.lastname: Zheng
authors.affiliation: State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China.
authors.forename: Xiaotong
authors.initials: X
authors.lastname: Qiu
authors.affiliation: Faculty of Veterinary Medicine, Swine and Poultry Infectious Diseases Research Center, University of Montreal, Quebec, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Roy
authors.affiliation: Faculty of Veterinary Medicine, Swine and Poultry Infectious Diseases Research Center, University of Montreal, Quebec, Canada.
authors.forename: Mariela
authors.initials: M
authors.lastname: Segura
authors.affiliation: Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, People's Republic of China.
authors.forename: Pengchen
authors.initials: P
authors.lastname: Du
authors.affiliation: State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Xu
authors.affiliation: Faculty of Veterinary Medicine, Swine and Poultry Infectious Diseases Research Center, University of Montreal, Quebec, Canada. marcelo.gottschalk@umontreal.ca.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Gottschalk
mesh_terms: D000818:Animals; D016667:Bacterial Capsules / Q000235:genetics*; D002170:Canada / Q000453:epidemiology; D004269:DNA, Bacterial / Q000235:genetics; D056426:Genetic Loci / Q000235:genetics; D060005:Genotyping Techniques / Q000662:veterinary; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011135:Polysaccharides, Bacterial / Q000235:genetics*; D017422:Sequence Analysis, DNA / Q000662:veterinary; D012703:Serotyping / Q000662:veterinary; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D017011:Streptococcus suis / Q000235:genetics*; D013552:Swine / Q000382:microbiology; D013553:Swine Diseases / Q000453:epidemiology / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial; D011135:Polysaccharides, Bacterial