Identification and characterisation of a novel conserved outer membrane protein from Neisseria meningitidis

We have identified a homologue of the adhesin AIDA-I of Escherichia coli in Neisseria meningitidis. This gene was designated nhhA (Neisseria hia homol ogue), as analysis of the complete coding sequence revealed that it is more closely related to the: adhesins Hia and Hsf of Haemophilus influenzae. Th e sequence of nhhA was determined from 10 strains, and found to be highly c onserved. Studies of the localisation by Western immunoblot analysis of tot al cell proteins and outer membrane complex preparations and by immunogold electron microscopy revealed that NhhA is located in the outer membrane. A strain survey showed that nhhA is present in 85/85 strains of N. meningitid is representative of all the major disease-associated serogroups, based on Southern blot analysis. It is expressed in the majority of strains tested b y Western immunoblot. (C) 2000 Published by Elsevier Science B.V. on behalf of the Federation of European Microbiological Societies.