title: An emerging zoonotic clone in the Netherlands provides clues to virulence and zoonotic potential of Streptococcus suis.
abstract: Streptococcus suis is a zoonotic swine pathogen and a major public health concern in Asia, where it emerged as an important cause of bacterial meningitis in adults. While associated with food-borne transmission in Asia, zoonotic S. suis infections are mainly occupational hazards elsewhere. To identify genomic differences that can explain zoonotic potential, we compared whole genomes of 98 S. suis isolates from human patients and pigs with invasive disease in the Netherlands, and validated our observations with 18 complete and publicly available sequences. Zoonotic isolates have smaller genomes than non-zoonotic isolates, but contain more virulence factors. We identified a zoonotic S. suis clone that diverged from a non-zoonotic clone by means of gene loss, a capsule switch, and acquisition of a two-component signalling system in the late 19th century, when foreign pig breeds were introduced. Our results indicate that zoonotic potential of S. suis results from gene loss, recombination and horizontal gene transfer events.
authors.affiliation: Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.|Department of Global Health-Amsterdam Institute for Global Health and Development, Academic Medical Center, University of Amsterdam, 1105 BM Amsterdam, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Willemse
authors.affiliation: Department of Paediatrics, School of Clinical Medicine, University of Cambridge, Cambridge CB2 0QQ, United Kingdom.
authors.forename: K J
authors.initials: KJ
authors.lastname: Howell
authors.affiliation: Department of Veterinary Medicine, School of Biological Sciences, University of Cambridge, Cambridge CB3 0ES, United Kingdom.
authors.forename: L A
authors.initials: LA
authors.lastname: Weinert
authors.affiliation: GD Animal Health, 7400 AA Deventer, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Heuvelink
authors.affiliation: Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
authors.forename: Y
authors.initials: Y
authors.lastname: Pannekoek
authors.affiliation: Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands.|Central Veterinary Institute part of Wageningen UR, 8221 RA Lelystad, The Netherlands.
authors.forename: J A
authors.initials: JA
authors.lastname: Wagenaar
authors.affiliation: Central Veterinary Institute part of Wageningen UR, 8221 RA Lelystad, The Netherlands.
authors.forename: H E
authors.initials: HE
authors.lastname: Smith
authors.affiliation: Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.|National Reference Laboratory of Bacterial Meningitis, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: van der Ende
authors.affiliation: Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.|Department of Global Health-Amsterdam Institute for Global Health and Development, Academic Medical Center, University of Amsterdam, 1105 BM Amsterdam, The Netherlands.|Oxford University Clinical Research Unit, Centre for Tropical Medicine, District 5, Ho Chi Minh City, Vietnam.
authors.forename: C
authors.initials: C
authors.lastname: Schultsz
mesh_terms: D000818:Animals; D023281:Genomics / Q000379:methods; D054884:Host-Pathogen Interactions / Q000235:genetics; D006801:Humans; D016920:Meningitis, Bacterial / Q000382:microbiology; D009426:Netherlands; D013290:Streptococcal Infections / Q000382:microbiology*; D017011:Streptococcus suis / Q000235:genetics*; D013552:Swine / Q000382:microbiology; D013553:Swine Diseases / Q000382:microbiology; D014774:Virulence / Q000235:genetics*; D037521:Virulence Factors / Q000235:genetics*; D015047:Zoonoses / Q000382:microbiology*
chemical_list: D037521:Virulence Factors