Serological evaluation of the outer membrane protein complexes of five saccharolytic intestinal Bacteroides species

The purpose of this investigation was to develop a serological procedure for rapid identification of the following five Bacteroides species: Bacteroides distasonis, Bacteroides fragilis, Bacteroides ovatus, Bacteroides uniformis, and Bacteroides vulgatus. The outer membrane fractions were assayed using SDS-polyacrylamide slab gel electrophoretic techniques. The species-specific protein band from each species as well as the group-specific protein were purified and used to develop an indirect enzyme-linked immunosorbent assay to detect the species-specific and group-specific protein from the outer membrane of five reference species. The sensitivity and specificity of the procedure were evaluated by indirect ELISA methodology using 506 clinical isolates of organisms in this group, ten other species of anaerobic gram-negative bacilli, and three species of aerobic gram-negative bacilli. Each species evaluated yielded unique outer membrane protein patterns, suggesting the potential for development of a rapid, species-specific diagnostic procedure.