Time course and site(s) of cytochrome c tyrosine nitration by peroxynitrite

The time course and site(s) of tyrosine nitration in horse cytochrome c by peroxynitrite is analyzed and a method of purifying nitrated cytochrome c product by cation-exchange high performance liquid chromatography (HPLC) is developed. The use of purified and well-characterized mono- and dinitrated cytochrome c species highlights the influence of nitration of specific tyrosines in cytochrome c functions.