A Neisseria meningitidis NMB1966 mutant is impaired for invasion of respiratory epithelial cells, survival in human blood and for virulence in vivo.

We sought to determine whether NMB1966, encoding a putative ABC transporter, has a role in pathogenesis. Compared to its isogenic wild-type parent strain Neisseria meningitidis MC58, the NMB1966 knockout mutant was less adhesive and invasive for human bronchial epithelial cells, had reduced survival in human blood and was attenuated in a systemic mouse model of infection. The transcriptome of the wild-type and the NMB1966 mutant was compared. The data are consistent with a previous functional assignment of NMB1966 being the ABC transporter component of a glutamate transporter operon. Forty-seven percent of all the differentially regulated genes encoded known outer membrane proteins or pathways generating complex surface structures such as adhesins, peptidoglycan and capsule. The data show that NMB1966 has a role in virulence and that remodelling of the outer membrane and surface/structures is associated with attenuation of the NMB1966 mutant.