CLONING AND EXPRESSION OF THE PORA GENE OF THE NEISSERIA-MENINGITIDISSTRAIN B-4-P1.15 IN ESCHERICHIA-COLI PRELIMINARY CHARACTERIZATION OF THE RECOMBINANT POLYPEPTIDE

The gene coding for the class 1 outer membrane protein from the Neisse ria meningitidis strain B385 (B:4:P1.15) was isolated by the Polymeras e Chain Reaction (PCR) and cloned into the Sma I cut M13mp18 vector. T hen, a Xba I restriction site was created by using an oligonucleotide- directed in vitro mutagenesis system at the start of the coding fragme nt. In order to express the protein, this fragment was fused to 180 ba se pairs corresponding to 60 amino acids from the N terminus of interl eukin-2 under the control of the tryptophan promoter (Ptrp). The expre ssion was confirmed by Western-blotting where the recombinant protein (PILM28) was detected by bactericidal monoclonal antibodies (MABs). Th e recombinant polypeptide was partially purified and used to elicit mu rine antibodies, able to recognize the meningococcal class 1 subtype 1 5.