Genetic and virulence-phenotype characterization of serotypes 2 and 9 of "Streptococcus suis" swine isolates

  1. Verena Blume
  2. Inmaculada Luque Moreno
  3. Ana Isabel Vela Alonso
  4. Carmen Borge
  5. Alfonso Maldonado García
  6. Lucas José Domínguez Rodríguez
  7. Carmen Tarradas Iglesias
  8. José Francisco Fernández-Garayzábal Fernández
Revista:
International microbiology: official journal of the Spanish Society for Microbiology

ISSN: 1618-1905

Año de publicación: 2009

Volumen: 12

Número: 3

Páginas: 161-166

Tipo: Artículo

Otras publicaciones en: International microbiology: official journal of the Spanish Society for Microbiology

Resumen

The aim of this study was to analyze the genetic characteristics and virulence phenotypes of Streptococcus suis, specifically, in clinical isolates of serotypes 2 and 9 (n = 195), obtained from diverse geographical areas across Spain. Pulsedfield gel electrophoresis (PFGE) typing identified 97 genetic profiles, 68% of which were represented by single isolates, indicative of a substantial genetic diversity among the S. suis isolates analyzed. Five PFGE profiles accounted for 33.3% of the isolates and were isolated from 38% of the herds in nine different provinces, indicative of the bacterium�s widespread distribution in the Spanish swine population. Representative isolates of the most prevalent PFGE profiles of both serotypes were subjected to multilocus sequence typing (MLST) analysis. The results indicated that serotypes 2 and 9 have distinct genetic backgrounds. Serotype 2 isolates belong to the ST1 complex, a highly successful clone that has spread over most European countries. In accordance with isolates of this complex, most serotype 2 isolates also expressed the phenotype MRP+EF+SLY+. Serotype 9 isolates belong to the ST61 complex, which is distantly related to the widespread European ST87 clone. Also, in contrast to most isolates of the European ST87 clone, which express the large variant MRP*, the majority of serotype 9 isolates (97.9%) did not express the protein. [Int Microbiol 2009; 12(3):161-166]