Application of iTRAQ Reagents to Relatively Quantify the Reversible Redox State of Cysteine Residues

Table 2

Relative quantification of the redox status of cys⁴⁴ in the ADH-1 peptide (40–60) in controls and after exposure to 5 mM H₂O₂. There is a decrease in both reversibly oxidized (47% to 26%) and reduced thiols (53% to 22%) and an increase in over oxidized thiols (52%) at this peroxide concentration.

Protein/peptide	Total detectable thiols (%)	Sample	Reversibly oxidized thiols (%)	Free thiols (%)	Overoxidized thiols (%)
Example	100	Control	(118/114)	1 − (118/114)	Not detectable
		Test	(121/114)	(116/114) − (121/114)	1 − (116/114)
ADH-1 (40–60)	100	Control	47	53	ND
		Test (5 mM H2O2)	26	22	52