Structural and Functional Studies of Bacterial Toxin-Antitoxin Systems

Abstract

TA systems have recently been linked to medically important processes such as biofilm formation, bacterial persistence after exposure to antibiotics, and bacterial pathogenesis. Toxin-Antitoxin (TA) systems are stable protein complexes consisting of a toxin, whose action is mechanistically distinct from exotoxins (e.g. botulinum, anthrax or cholera toxins), in complex with an antitoxin, its specific inhibitor. The release of TA toxin occurs under specific conditions (e.g. stress). TA toxins have a bacteriostatic effect that can lead to cell death if sustained. Although the mechanisms of action for a few TA toxins have been uncovered, the intracellular targets of many others have not been identified. Our latest structural and functional data on such complexes will be presented.