Table 1.

Criteria for covalent modifications to serve as a regulatory mechanism. Chart lists the different criteria that must be met for a posttranslational modification to serve as a regulatory mechanism. Criteria were generated based the function of binary switches, like phosphorylation, in the control of protein function through alterations in structure. The Table was adapted from [12].

Criteria	Sulfenylation	Protein S-glutathionylation
Change function of protein	Yes	Yes
Occurs in response to physiological stimuli	Yes	Yes
Modification is rapid and enzymatically mediated	Kinetically slow and not enzymatically mediated	Yes
Modification is controlled and site specific	Unknown	Yes
Modification is stable and does not lead to unwanted side reactions	No	Yes
Modification is reversible	Yes	Yes