The mechanisms governing the expression
Our previous experiments revealed that upon contact with blood, expression and secretion of T3SS components is strongly increased. Furthermore, we have identified two new factors that contribute to proper function of T3SS in B. pertussis. One of them, BtcB, was identified and characterized as a T3SS chaperone that specifically interacts with anti-sigma factor BtrA and facilitates its secretion. Predictions made by artificial intelligence system AlphaFold support the chaperone function of BtcB toward BtrA and outline the structural basis for the interaction of BtrA with its target BtrS.
