title: Identification of the capsular polysaccharides in Staphylococcus aureus clinical isolates by PCR and agglutination tests.
abstract: Staphylococcus aureus is a major cause of nosocomial and community-acquired infections. The predominance of two capsular polysaccharides, types 5 and 8, on the surface of clinical isolates led to the development of a conjugate vaccine (StaphVAX) based on capsular polysaccharides types 5 and 8 conjugated to a carrier protein. We have studied the capsular phenotypes and genotypes of 195 isolates representative of all clinical syndromes that encompassed both hospital and community-acquired infections. These isolates were mainly detected in France between January 2001 and December 2004. In this population, most of clinical isolates (87%) expressed either capsular polysaccharide type 5 (42%) or 8 (45%), whereas 13% were nontypeable by the serotyping method with antibodies specific to capsular polysaccharide type 5 or 8. These 26 nontypeable strains were further serotyped and were demonstrated to express the cell wall surface antigen 336, a polyribitol phosphate N-acetylglucosamine, which resembles cell wall teichoic acid. Among methicillin-resistant Staphylococcus aureus (MRSA) strains, we found a predominance of serotype 5 for 64% of strains, whereas MSSA isolates were predominantly capsular serotype 8 (60%). All S. aureus clinical isolates included in the present study have been investigated by PCR method, demonstrating that all isolates carried either the cap5 or the cap8 locus.
authors.affiliation: INSERM, E0230, Lyon, F-69008, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Verdier
authors.forename: Geraldine
authors.initials: G
authors.lastname: Durand
authors.forename: Michele
authors.initials: M
authors.lastname: Bes
authors.forename: Kimberly L
authors.initials: KL
authors.lastname: Taylor
authors.forename: Gerard
authors.initials: G
authors.lastname: Lina
authors.forename: François
authors.initials: F
authors.lastname: Vandenesch
authors.forename: Ali I
authors.initials: AI
authors.lastname: Fattom
authors.forename: Jerome
authors.initials: J
authors.lastname: Etienne
mesh_terms: D000372:Agglutination Tests / Q000379:methods*; D016667:Bacterial Capsules / Q000235:genetics; D017714:Community-Acquired Infections / Q000382:microbiology; D003428:Cross Infection / Q000382:microbiology; D005602:France; D006801:Humans; D016106:Methicillin Resistance; D016133:Polymerase Chain Reaction / Q000379:methods*; D011135:Polysaccharides, Bacterial / Q000145:classification* / Q000235:genetics; D012703:Serotyping; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification
chemical_list: D011135:Polysaccharides, Bacterial; C054106:capsular polysaccharide, type 5, Staphylococcus aureus; C064836:capsular polysaccharide, type 8, Staphylococcus aureus