title: Eight Novel Capsular Polysaccharide Synthesis Gene Loci Identified in Nontypeable Streptococcus suis Isolates.
abstract: Streptococcus suis is an important pathogen of pigs and may cause serious disease in humans. Serotyping is one of the important diagnostic tools and is used for the epidemiological study of S. suis. Nontypeable S. suis strains have been reported in many studies; however, the capsular polysaccharide (CPS) synthesis cps loci of nontypeable strains have not been analyzed. In this study, we investigated the genetic characteristics of cps loci in 78 nontypeable strains isolated from healthy pigs. Eight novel cps loci (NCLs) were found, and all of them were located between the orfZ-orfX region and the glf gene. All NCLs possess the wzy and wzx genes, strongly suggesting that the CPSs of these NCLs were synthesized using the Wzx/Wzy-dependent pathway. The cps genes found in the 78 isolates were assigned to 96 homology groups (HGs), 55 of which were NCL specific. The encapsulation of the 78 isolates was also examined using transmission electron microscopy. Fifty-three isolates were found to have a capsule, and these were of varied thicknesses. Our data enhance our understanding of the cps gene cluster diversity of nontypeable S. suis strains and provide insight into the evolution of the S. suis capsular genes.
authors: 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: Han
authors: H
authors: Zheng
authors: 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: Shaobo
authors: S
authors: Ji
authors: 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: Zhijie
authors: Z
authors: Liu
authors: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors: Ruiting
authors: R
authors: Lan
authors: 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: Ying
authors: Y
authors: Huang
authors: 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: Xuemei
authors: X
authors: Bai
authors: Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculty of Veterinary Medicine, University of Montreal, Montreal, Québec, Canada.
authors: Marcelo
authors: M
authors: Gottschalk
authors: 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 xujianguo@icdc.cn.
authors: Jianguo
authors: J
authors: Xu
mesh_terms: D000818:Animals; D016667:Bacterial Capsules / Q000737:chemistry* / Q000648:ultrastructure; D015373:Bacterial Typing Techniques; D019295:Computational Biology; D005798:Genes, Bacterial; D056426:Genetic Loci; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017011:Streptococcus suis / Q000145:classification / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D013552:Swine
chemical_list: D011135:Polysaccharides, Bacterial