Identification of new epidemiological molecular markers by comparative proteomics of serogroup A meningococcal isolates from three pandemic waves

We previously described the first reference map for the proteome of one strain of serogroup A Neisseria meningitidis (MenA), a major cause of epidemic meningitis in humans. As a preliminary finding, in that work we noted that 2-DE protein maps of closely related MenA isolates from different epidemics spreads could be easily compared to detect minor differences and that 2-DE phenotypes attributable to the well-known epidemiological marker tbpB agreed with the genoclouds model of MenA epidemiological variation during pandemic waves. We explored here the possibility that an extended comparative study of 2-DE maps of isolates representative of the nine genoclouds described by Achtman and collaborators could be used to discriminate between strains otherwise undistinguishable. We showed the example of 14 proteins with different 2-DE spot patterns in different genoclouds that could be considered as putative tracers for alike-strains discrimination. We introduce the novel concept that comparative proteomics can be useful in identifying new epidemiological markers for N. meningitidis.