Peroxynitrite has recently been implicated in the inactivation of many enzymes. However,
little has been reported on the structural basis of the inactivation reaction. This study
proposes that nitration of a specific tyrosine residue is responsible for inactivation of
recombinant human mitochondrial manganese-superoxide dismutase (Mn-SOD) by
peroxynitrite. Mass spectroscopic analysis of the peroxynitrite-inactivated Mn-SOD showed
an increased molecular mass because of a single nitro group substituted onto a tyrosine …