EXPRESSION IN ESCHERICHIA-COLI OF THE IPDA GENE, PROTEIN-SEQUENCE ANALYSIS AND IMMUNOLOGICAL CHARACTERIZATION OF THE P64K PROTEIN FROM NEISSERIA-MENINGITIDIS

By making use of recombinant DNA technology it is possible to characte rize meningococcal outer membrane proteins (OMPs) capable of stimulati ng a host immune response. The IpdA gene, which codes for an OMP (P64k ) from Neisseria meningitidis, was cloned in Escherichia coli, The rec ombinant protein was recognized by sera from patients convalescing fro m meningococcal disease. The monoclonal antibodies obtained against th e recombinant protein recognized the natural protein on a Western blot , and monoclonal antibody 114 was assayed in ELISA with a panel of 85 N. meningitidis strains. The protein was recognized in 81 strains (95. 3%); the strains that were not recognized were neither epidemic nor is olated from systemic disease. The complete amino acid sequence of P64k was obtained by automatic sequencing and MS.