Bacterial toxins: virulence factors and cell, biology tools

Many pathogenic bacteria produce protein toxins. Studying their mode of action presents a double interest. On one hand, toxins play a role in the host-bacteria interaction, and they can influence the clinical course of bacterial infections. On the other hand, toxins are also spectacular examples of cellular functions diversion. New bacterial toxin activities have been described over the last decade, and they hare become widely used as cell biology tools, since they target important regulators of cell. functions with very tight specificity. Bacterial toxins have been for instance instrumental in the discovery: of the role played by small GTPases of the Rho family in the control of:the actin cytoskeleton organization, and in the study of SNAREs molecules in vesicular traffic. Bacterial toxins are often organized in different domains that fulfill the following functions: (1) a toxic domain, very often an enzyme; (2) a domain that interacts with a cell surface receptor; (3) a domain that allo rvs active domain delivery of the catalytic subunit in the cytoplasm and which acts as a molecular syinge across the cell membrane. The study of the mode of action of bacterial toxins is therefore an active field of research in both microbiology and cellular biology.