Distribution of specific DNA sequences among pathogenic and commensal Neisseria species.

Several traits, including pili and the outer membrane proteins P.II and H.8, have been associated with pathogenic Neisseria species. We examined several Neisseria species for DNA sequence homology to cloned pilin, P.II, and H.8 genes. Strains of Neisseria gonorrhoeae and N. meningitidis showed hybridization to all of these genes. Commensal strains showed little hybridization to any of these genes. Strains of N. lactamica and N. cinerea showed intermediate patterns of hybridization. Generally, organisms that expressed a given trait showed DNA homology to the corresponding cloned gene. However, we observed pili on some commensal strains that did not show hybridization to the cloned gonococcal pilin gene.