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Heme/O2/*NO nitric oxide dioxygenase (NOD) reactivity: phenolic nitration via a putative heme-peroxynitrite intermediate.

ABSTRACT: An oxy-heme complex, the heme-superoxo species (tetrahydrofuran)(F(8))Fe(III)-(O(2)(*-)) (2) (F(8) = an ortho-difluoro substituted tetraarylporphyrinate), reacts with nitrogen monoxide (*NO; nitric oxide) to produce a nitrato-iron(III) compound (F(8))Fe(III)-(NO(3)(-)) (3) (X-ray). The chemistry mimics the action of *NO Dioxygenases (NODs), microbial and mammalian heme proteins which facilitate *NO detoxification/homeostasis. A peroxynitrite intermediate complex is implicated; if 2,4-di-tert-butylphenol is added prior to *NO reaction with 2, o-nitration occurs giving 2,4-di-tert-butyl-6-nitrophenol. The iron product is (F(8))Fe(III)-(OH) (4). The results suggest that heme/O(2)/*NO chemistry may lead to peroxynitrite leakage and/or exogenous substrate oxidative/nitrative reactivity.

SUBMITTER: Schopfer MP

PROVIDER: S-EPMC2747244 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Heme/O2/*NO nitric oxide dioxygenase (NOD) reactivity: phenolic nitration via a putative heme-peroxynitrite intermediate.

Schopfer Mark P MP Mondal Biplab B Lee Dong-Heon DH Sarjeant Amy A N AA Karlin Kenneth D KD

Journal of the American Chemical Society 20090801 32

An oxy-heme complex, the heme-superoxo species (tetrahydrofuran)(F(8))Fe(III)-(O(2)(*-)) (2) (F(8) = an ortho-difluoro substituted tetraarylporphyrinate), reacts with nitrogen monoxide (*NO; nitric oxide) to produce a nitrato-iron(III) compound (F(8))Fe(III)-(NO(3)(-)) (3) (X-ray). The chemistry mimics the action of *NO Dioxygenases (NODs), microbial and mammalian heme proteins which facilitate *NO detoxification/homeostasis. A peroxynitrite intermediate complex is implicated; if 2,4-di-tert-but ...[more]

PMID: 19627146

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