Isolation and partial characterization of the reduction-modifiable protein of Neisseria gonorrhoeae

We have isolated and purified the reduction-modifiable protein (protein III) from several strains of Neisseria gonorrhoeae. We have found them to be basic proteins (pI 8.6) and virtually identical. A similar but not identical protein was isolated from a meningococcal strain. Antibodies raised against this purified protein would absorb to whole bacteria, confirming that the protein is exposed on the surface of the organism.