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W Karakawa

Publications and source records attributed to W Karakawa.

3 recordsLinked to original sources
PubMed1992

Capsular polysaccharide serotyping scheme for Staphylococcus epidermidis.

A scheme for the capsular typing of Staphylococcus epidermidis that is based on direct slide agglutination between proteinase-treated bacterial cells and specific antisera is described. Antisera were prepared from serum from rabbits immunized with two selected strains of encapsulated S. epidermidis isolated from bacteremic patients. Antisera were shown to be type specific and designated type 1 and type 2. Blood isolates of S. epidermidis from hospitals in different locations within the United States and Europe were serotyped, and it was found that over 90% of all strains were of type 1 or type 2. Type-specific antibodies mediated type-specific opsonophagocytosis and killing of S. epidermidis. The specificity was shown to be due to two distinct capsular polysaccharides. The data presented in this report may open a new window on the pathogenesis of S. epidermidis which could lead to the development of new vaccines and therapies.

Antibodies, Bacterial↗
PubMedDate not supplied

Capsular polysaccharide serotypes of coagulase-positive staphylococci associated with tenosynovitis, osteomyelitis, and other invasive infections in chickens and turkeys: evidence for new capsular types.

To study the role of capsular polysaccharides in staphylococcal infections in chickens and turkeys, we surveyed 101 coagulase-positive isolates obtained from investigators in geographically diverse locales in the United States and Canada. Fifty-six isolates were obtained from chickens; 51 (91%) were type 5, and 5 (9%) were type 8. Forty isolates were obtained from turkeys; 13 (33%) were type 5, 15 (38%) were type 8, and 12 (29%) were untypable. Five type 5 isolates were obtained from poultry of uncertain species. Two untypable turkey isolates were studied further. Rabbit serum obtained after immunization with formalin-killed staphylococci was type-specific as assessed by a tube agglutination test and promoted opsonophagocytosis of the isolate that had been used for immunization. Chromatography of carboxy-reduced capsular polysaccharide from one of the isolates suggested that mannoseaminouronic acid was present in the unreduced polysaccharide. The spectrum obtained by 13C-nuclear magnetic resonance suggested the presence of N-acetyl sugars such as mannoseaminouronic acid and 6-deoxy sugars such as N-acetyl fucosamine. The structure of the polysaccharide differed from that of the type 5 and type 8 capsular polysaccharides. Thus, poultry isolates can be classified into at least four serotypes on the basis of their capsular polysaccharides. This observation provides a new focus for investigation into the epidemiology and virulence determinants of this important pathogen in chickens and turkeys.

Animals↗