Introduction to approaches and tools for the evaluation of protein cysteine oxidation.

Oxidative modifications of cysteine thiols in cellular proteins are pivotal to the way signal-stimulated reactive oxygen species are sensed and elicit appropriate or sometimes pathological responses, but the dynamic and often transitory nature of these modifications offer a challenge to the investigator trying to identify such sites and the responses they elicit. A number of reagents and workflows have been developed to identify proteins undergoing oxidation and to query the timing, extent and location of such modifications, as described in this minireview. While no approach is perfect to capture all the redox information in a functioning cell, best practices described herein can enable considerable insights into the "redox world" of cells and organisms.