Table 5.

Summary of covalent oxidative modifications of amino acids of rabbit hemopexin

Data summary: the endogenous nitration of Tyr-201 (rabbit) is conserved on Tyr-199 (human) and Tyr-118 (rat). Significantly, in the 3D crystal structure of hemopexin, Tyr-201 and Tyr-222 interact with the propionate oxygen of heme ring D, and Tyr-229 also resides near the bound heme (17) and see Fig. 2B. There were three additional nitration sites, Tyr-121, Tyr-317, and Tyr-325 (see Table 2). The amino acids and their modifications that were not unambiguously identified by MASCOT (summarized in Table 3), are shown here in square brackets. t-Bu, t-butylation.

Amino acid	Covalent oxidative modifications
Tyr-121	Nitration
Tyr-201	Nitration	t-Bu
Tyr-222		Mono-Cl		(di-Cl)	(t-Bu)
Tyr-229	Nitration	t-Bu	(Mono-Cl)	(di-Cl)
Tyr-317	Nitration
Tyr-325	Nitration
Tyr-339		Mono-Cl
Trp-119		Oxidation