What is the timescale of disulfide bond formation in a given protein? What influences it? Finally, how does one actually measure it?
From what I understand, the reduction and oxidation of bonds happens on the order of 10-8s. However, it appears that the timescale of disulfide bond formation in macromolecules scales with the size of the macromolecule.
I agree that the actual redox process is very fast. The rate limiting issue with proteins and other macromolecues involves the reactive groups finding each other. Thus, from the time of translation to the time of disulfide formation, the peptide chains need to fold properly. Perhaps other subunits need to be assembled and attached. Once everything is in the right place, the disulfide bond should form quickly provided there is an appropriate oxidant present.
You could measure the rate of the entire process by attaching reporters to positions on the protein - say a fluorophore and a quencher. When the process is complete, the quencher and the fluorophore are close in space, and fluorescence stops. This approach will measure the overall rate of the entire process. I am not sure if you can separate out the different components, e.g. specifically the S-S bond forming. I can't point to a specific paper where this is strategy is used, since I am away from my usual computer that likes my journal subscriptions. Hopefully I will be able to update my answer.
