title: Pathogenicity of piliated and encapsulated Bacteroides fragilis.
abstract: Of 20 isolates of the Bacteroides fragilis group, only three were encapsulated (C+) and these induced abscesses in mice. After coinoculation with live, formalized or capsular material from other bacteria seven other isolates formed abscesses. The Bacteroides recovered from these abscesses were C+; those that had been inoculated with Klebsiella had pili-like and bacteriophage-like structures. Once encapsulated, the Bacteroides isolates induced abscesses when injected alone.
mesh_terms: D000038:Abscess / Q000382:microbiology; D000818:Animals; D001439:Bacteroides / Q000472:pathogenicity / Q000648:ultrastructure; D001442:Bacteroides Infections / Q000150:complications / Q000382:microbiology; D001441:Bacteroides fragilis / Q000472:pathogenicity* / Q000648:ultrastructure; D010861:Fimbriae, Bacterial / Q000502:physiology* / Q000648:ultrastructure; D007710:Klebsiella Infections / Q000150:complications / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000472:pathogenicity; D051379:Mice