Consideration of a new catalytic role for the thiazolium sulfur atom of the coenzyme thiamine pyrophosphate

A review of the mechanism of action of thiamine pyrophosphate is presented in brief detail along with a new proposal for the role of the sulfur atom of the thiazolium ring of the coenzyme. Evidence is presented to support the idea that sulfur plays a catalytic role in stabilizing negative charge developing in the transition states of the biological reactions.