Table 6. Overview of protein modifications induced by reactive oxidants.

Oxidant	Major sites of reaction
HO•	All residues
RO•	Most residues
ROO•	Cys, Met, Trp, Tyr
CO3−•	Cys, Met, Tyr, Trp, His
NO2•	Cys, Tyr/Trp radicals
O2−•	Superoxide dismutase, some transition metal ions, Fe–S clusters, Tyr/Trp radicals
1O2	Cys, Met, Trp, Tyr and His
HOCl/HOBr	Cys, Met, cystine, His, α-amino group, Lys, Trp
Peroxynitrous acid (ONOOH)	Cys, Met, Tyr, Trp, selenocysteine
UVB light	Trp, Tyr, cystine
Reactive aldehydes	Cys, Arg, Lys, His, α-amino group
HOSCN	Cys, selenocysteine
H2O2	Cys, selenocysteine