Proteins associated with environmental survival of the pathogen <i>Neisseria meningitidis</i>

Previously, we reported the persistence of the bacterial pathogen <i>Neisseria meningitidis</i> on fomites, indicating a potential route for environmental transmission. The current goal was to identify proteins that vary among strains of meningococci that have differing environmental survival. We carried out a proteomic analysis of two strains that differ in their potential for survival outside the host. The Group B epidemic strain NZ98/254 and Group W carriage strain H34 were cultured either at 36 °C, 5% CO₂, and 95% relative humidity (RH) corresponding to host conditions in the nasopharynx, or at lower humidities of 22% or 30% RH at 30 °C, for which there was greater survival on fomites. For NZ98/254, the shift to lower RH and temperature was associated with increased abundance of proteins involved in metabolism, stress responses, and outer membrane components, including pili and porins. In contrast, H34 responded to lower RH by decreasing the abundance of multiple proteins, indicating that the lower viability of H34 may be linked to decreased capacity to mount core protective responses. The results provide a snapshot of bacterial proteins and metabolism that may be related to normal fitness, to the greater environmental persistence of NZ98/254 compared to H34, and potentially to differences in transmission and pathogenicity.