Análise genômica de Burkholderia mallei e Burkholderia pseudomallei: dois patógenos de primeira grandeza e de genomas surpreendentemente complexos

Abstract

The Burkholderia genus holds over 40 species of gram-negative bacteria, including genomovars early identified as part of B. cepacia complex (Bcc), besides B. mallei (causative agent of equine glanders) and B. pseudomallei (causative agent of human melioidosis or pseudoglanders). Natural B. mallei and B. pseudomallei zoonotic infections have largely been eradicated/controlled and human infection is extremely rare, but renewed interest in these organisms parallels their classification as category B biothreat agents, the lack of any effective vaccine available for them and the serious risk of aerosol transmission, a great concern for public health surveillance. Both diseases are very ancient, but relatively little is known about details concerning virulence mechanisms in glanders and melioidosis. Here we apply bioinformatics resources and tools to investigate B. mallei and B. pseudomallei sequenced genomes, their putative genes (and coded proteins) in a pathogenomics approach aiming at the in silico identification of virulence genes potentially associated with a key-lesion of both diseases, the granuloma (or piogranuloma) formation. Granulomas are localized chronic inflammatory responses that are able to keep the pathogen inside of them and are, thus, critical sites of infection. Our results help to build a panel of eighteen (18) putative ortologs, which can be excellent targets for future experimental screenings that might lead to genetic characterizations of their functions in terms of granulomatous genesis within Burkholderia infections.