Copyright © 1992, American Society for Microbiology Ability of Gonococcal and Meningococcal Lipooligosaccharides

We investigated whether the striking difference in severity of coagulopathy observed between bacterial sepsis involving Neisseria meningitidis and Neisseria gonorrhoeae species is related to species-dependent abilities to directly activate coagulation. Using lipooligosaccharide (LOS)-activated gelation ofLimulus amebocyte lysate, we compared the relative abilities of outer membrane LOS of 10 N. meningitidis and 10 N. gonorrhoeae strains to initiate coagulation. A wide range of procoagulant potencies was observed for each species, and there was significant overlap of potencies between species. Relative biological activities did not correlate with the oligosaccharide components as defined by LOS molecular weight or specific antigenic epitopes. Purified lipid A of two LOS strains of different potency demonstrated relative procoagulant biological activities similar to those of their parent LOSs. When these lipid A preparations were further separated by thin-layer chromatography, the most polar component of each lipid A possessed the majority of the procoagulant activity. We conclude that the ability of neisserial LOS to initiate coagulation ofLimulus lysate is a property of the lipid A portion of the molecule and is most likely determined by fine structural differences in the lipid A which are independent of species. Neisserial organisms are major human pathogens, and much of the pathogenicity of both gonococcal (GC) an