title: Subtyping isolates of Haemophilus influenzae type b by outer-membrane protein profiles.
abstract: Outer-membrane proteins from isolates of Haemophilus influenzae type b were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Sarcosinate-insoluble membrane preparations contained one peptide with a molecular weight of 16,000 and four major peptides with molecular weights of 25,000-40,000. A peptide with a molecular weight of 49,000 (50,000 in some strains) was observed after the samples were heated at 100 C. Fifty-one isolates obtained from patients hospitalized with invasive diseases, primarily meningitis, could be subclassified into nine categories based on reproducible and clearly resolvable differences in the outer-membrane protein profiles. Five categories accounted for 92% of the isolates. Complete concordance was observed in subtypes of strains obtained from epidemiologically related cases and contacts. Thus, comparison of the major outer-membrane proteins of H. influenzae type b is a useful technique for investigating the transmission of the organism and may provide a basis for further immunologic characterization of the outer-membrane proteins.
mesh_terms: D000818:Animals; D003902:Detergents / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D006192:Haemophilus Infections / Q000382:microbiology; D006193:Haemophilus influenzae / Q000145:classification* / Q000254:growth & development; D008565:Membrane Proteins / Q000032:analysis*; D008970:Molecular Weight; D051381:Rats; D012703:Serotyping; D012995:Solubility
chemical_list: D003902:Detergents; D008565:Membrane Proteins