title: Microcapsules on Streptococcus mutans serotypes by electron microscopy.
abstract: Extracellular microcapsules have been demonstrated on cells of most serotypes of Streptococcus mutans by electron microscopy, using bacterial strains of the various serotypes and peroxidase labeled or unlabeled immune serum. A correlation was noted between the amount of capsular substance on the strains of S mutans examined and degree of antigenicity as expressed by the indirect fluorescent antibody (FA) title. A serotype d strain was shown to lose both antigenicity as determined by the FA reaction and capsular material as seen by electron microscopy with repeated in vitro passage. When 10% unheated rabbit serum was added to the medium, antigenicity and capsular material were restored.
mesh_terms: D005455:Fluorescent Antibody Technique; D007158:Immunologic Techniques; D008264:Macrophages / Q000166:cytology; D008854:Microscopy, Electron; D010544:Peroxidases; D013194:Staining and Labeling; D013291:Streptococcus / Q000648:ultrastructure*; D013295:Streptococcus mutans / Q000145:classification / Q000648:ultrastructure*
chemical_list: D010544:Peroxidases