Isolation and preliminary biochemical characterization of the gonococcal H.8 antigen.

We have presented a method for the extraction and isolation of the gonococcal H.8 antigen. There was no evidence of contamination by other gonococcal proteins, phospholipids, or LPS. The purified H.8 antigen was subjected to preliminary analysis and appeared to be a proteolipid consisting of both protein and lipid components. The amino acid composition was unusual; the peptide portion of the antigen was an alanine and proline-rich molecule that lacked aromatic and sulfur-containing amino acids. The overall amino acid composition is hydrophobic. A lipid constituent was also identified; it was made up of at least two lipid components, which were unique to the H.8 molecule. The chemical nature of the association of the protein and lipid is presently unknown, but it is clearly a tenacious one.