Exploiting molecular virulence determinants in Burkholderia to develop vaccine antigens

The Burkholderia genus is a highly diverse group of species that are distributed throughout a wide range of environments and habitats. Among this group, which is remarkable for its adaptability to a wider range of environmental conditions including disinfectants and organic solvents, are a subgroup that represents some of the most difficult to treat infections. This subgroup includes Burkholderia pseudomallei, the causative agent of melioidosis; B. mallei, the causative agent of glanders and B. cepacia complex (Bcc) which causes opportunistic infections in people with cystic fibrosis and immunocompromised patients. The latter pathogen is itself a group of 18 distinct, but, closely related species. The adaptability of this group allows the expression of a rich selection of molecular virulence determinants to facilitate its survival in the diverse habitats that it colonises. This review will describe a selection of these associated with human infection; comparing them across the three pathogens and highlighting their potential roles as vaccine candidates. Better integration of the knowledge on the pathogenesis and molecular determinants of virulence for these Burkholderia spp may allow the development of more efficacious vaccines.