Mechanism of stator assembly and incorporation into the flagellar motor

Abstract

In many cases, conformational changes in proteins are related to their functions, and thereby inhibiting those changes causes functional defects. One way to perturb such conformational changes is to covalently link the regions where the changes are induced. Here, I introduce an example in which an intramolecular disulfide crosslink in the stator protein of PomB, introduced based on its crystal structure, reversibly inhibits the rotation of the flagellar motor, and I detail how we analyzed that phenotype. In this Chapter, first I describe how we monitor the motility inhibition and restoration by controlling disulfide bridge formation, and secondly how we detect intramolecular disulfide crosslinks, which are sometimes difficult to monitor by mobility shifts on SDS-PAGE gels.