Independent evolution of the core and accessory gene sets in the genus Neisseria: insights gained from the genome of Neisseria lactamica isolate 020-06.

摘要: The genus Neisseria contains two important yet very different pathogens, N. meningitidis and gonorrhoeae, in addition to non-pathogenic species, of which lactamica is the best characterized. Genomic comparisons these three bacteria will provide insights into mechanisms evolution pathogenesis this group organisms, are applicable understanding processes more generally. Non-pathogenic exhibits similar population structure levels diversity meningococcus, whilst gonococci essentially recent descendents a single clone. All species share common core gene set estimated comprise around 1190 CDSs, corresponding about 60% genome. However, some nucleotide sequence within genome particular each group, indicating that cross-species recombination rare shared set. Other than meningococcal cps region, encodes polysaccharide capsule, relatively few members large accessory pool exclusive one frequent. groups represent coherent biological genetic groupings appear be maintained by low rates inter-species horizontal exchange There extensive evidence for among positively selected genes hitch-hiking housekeeping with other loci. It not possible define 'pathogenome' organisms disease causing phenotypes therefore likely complex, polygenic, various disease-associated observed.