Electrophoretic heterogeneity and interstrain variation of the lipopolysaccharide of Haemophilus influenzae

J Infect Dis. 1983 Sep;148(3):492-9. doi: 10.1093/infdis/148.3.492.


Lipopolysaccharide (LPS) was extracted from 50 isolates of Haemophilus influenzae by a rapid micromethod and was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining. LPS isolated by this method was electrophoretically indistinguishable from conventionally purified LPS but lacked the large degree of heterogeneity indicative of variable polymerization of O-side-chain repeating units; one to four bands appeared in gels. Electrophoretic profiles of LPS from H influenzae type b varied among strains and were useful for subtyping. Thirty-three isolates of type b were classified into 11 subtypes on the basis of stable band mobilities. Certain isolates of identical outer-membrane-protein subtype differed in LPS subtype. The LPS profiles of non-b, typable strains of H influenzae were generally similar in microheterogeneity to those of type b strains, while those of untypable isolates usually displayed less electrophoretic variation.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Electrophoresis, Polyacrylamide Gel
  • Haemophilus Infections / microbiology
  • Haemophilus influenzae / analysis*
  • Haemophilus influenzae / classification
  • Haemophilus influenzae / isolation & purification
  • Humans
  • Lipopolysaccharides / classification*
  • Lipopolysaccharides / isolation & purification
  • Serotyping


  • Lipopolysaccharides