Distribution of capsular types and production of muramidase-released protein (MRP) and extracellular factor (EF) of Streptococcus suis strains isolated from diseased pigs in seven European countries.
Streptococcus suis strains (n=411), isolated from diseased pigs in seven European countries were serotyped using specific antisera against serotype 1 to 28, and were phenotyped on the basis of their muramidase-released-protein (MRP) and extracellular-factor protein (EF) production. Overall, S. suis serotype 2 appeared to be most prevalent (32%), followed by serotype 9 (20%) and serotype 1 (12%). Serotype 2 was most frequently isolated in France, Italy and Spain, whereas serotype 9 was most frequently isolated in Belgium, The Netherlands and Germany. In the United Kingdom serotypes 1 and 14 were most frequently isolated. High percentages of S. suis serotype 1, 2, 1/2 and 14 strains, isolated from tissues associated with S. suis infections such as brain, serosa, joint, heart and organs expressed the EF-protein, indicating that in these serotypes expression of EF is likely to be associated with virulence. In contrast, strains belonging to serotype 7 and 9, isolated from tissues associated with S. suis infections did not produce EF. These results strongly suggest that in the serotypes 7 and 9 EF expression is not related to virulence. More than 80% of the S. suis serotype 9 strains produced an MRP* protein, a high molecular variant of the 136kDa MRP. Expression of MRP* in serotype 9 strains is possibly associated with virulence.
Wisselink
H J
HJ
Department of Bacteriology, Institute for Animal Science and Health, P.O. Box 65, 8200 AB, Lelystad, Netherlands. h.j.wisselink@id.wag-ur.nl
Smith
H E
HE
Stockhofe-Zurwieden
N
N
Peperkamp
K
K
Vecht
U
U
D000367:Age Factors; D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000911:Antibodies, Monoclonal; D016667:Bacterial Capsules / Q000737:chemistry / Q000145:classification; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000378:metabolism; D015153:Blotting, Western / Q000662:veterinary; D001921:Brain / Q000382:microbiology; D015169:Colony Count, Microbial; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D005060:Europe; D006321:Heart / Q000382:microbiology; D008168:Lung / Q000382:microbiology; D012703:Serotyping / Q000662:veterinary; D012704:Serous Membrane / Q000382:microbiology; D013290:Streptococcal Infections / Q000382:microbiology / Q000662:veterinary*; D017011:Streptococcus suis / Q000737:chemistry / Q000145:classification / Q000472:pathogenicity*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*; D014774:Virulence
D000911:Antibodies, Monoclonal; D001426:Bacterial Proteins; C082316:Epf protein, Streptococcus suis