question: What is the mode of action of the Tc toxins?
answer: The toxin complex (tc) genes of bacteria comprise a large and growing family whose mode of action remains obscure. Tc toxins are widely distributed among different gram-negative and gram-positive bacteria, where they act as pathogenicity factors. Tripartite Tc toxin complexes of bacterial pathogens perforate the host membrane and translocate toxic enzymes into the host cell, including in humans. The underlying mechanism is complex but poorly understood.