Burkholderia pseudomallei Toxins and Clinical Implications

Abstract

Burkholderia pseudomallei is the causal agent of melioidosis. In spite of ongoing studies, the molecular mechanisms underlying toxin-induced pathogenesis of this bacterium are not clearly elucidated for this potential biological warfare pathogen. In this review, we highlight current information of B. pseudomallei toxins and their roles in pathophysiological effects in various experimental models. Several secretary proteins/lethal factors show lethal toxicity to cells in culture via filtrates of B. pseudomallei culture. These toxins are released in culture from strains isolated from soil, animals and humans. Toxins are also found in infected patients, which strongly correlate with severity of melioidosis. Melioidosis progression begins with an environmental reservoir and bacterial attachment in the host, invasion of epithelial/macrophage cells and subsequent intercellular spread. The molecular and cellular basis of pathogenesis in melioidosis will provide a better, rational understanding toward design and development of new drugs with novel mechanisms of action.