Although carbonyl formation is a major oxidative modification induced by peroxynitrite, nitration of tyrosine residues is an indicator of peroxynitrite involvement.
Peroxynitrite is a source of hydroxyl radical-like reactivity, and it directly oxidizes proteins and other macromolecules with resultant carbonyl formation from side-chain and peptide-bond cleavage.
Fortunately for the future of the battery, it turns out its color molecules are also carriers of carbonyl and hydroxyl groups that make it ripe for use as an electrode and that purpurin is far easier to process than other organic materials: "These aromatic systems are electron-rich molecules that easily coordinate with lithium, " said CCNY Professor George John.