NRVS Studies of the Peroxide Shunt Intermediate in a Rieske Dioxygenase and Its Relation to the Native FeII O2 Reaction

Kyle D. Sutherlin, Brent S. Rivard, Lars H. Böttger, Lei V. Liu, Melanie S. Rogers, Martin Srnec, Kiyoung Park, Yoshitaka Yoda, Shinji Kitao, Yasuhiro Kobayashi, Makina Saito, Makoto Seto, Michael Hu, Jiyong Zhao, John D. Lipscomb, Edward I. Solomon

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)


The Rieske dioxygenases are a major subclass of mononuclear nonheme iron enzymes that play an important role in bioremediation. Recently, a high-spin FeIII-(hydro)peroxy intermediate (BZDOp) has been trapped in the peroxide shunt reaction of benzoate 1,2-dioxygenase. Defining the structure of this intermediate is essential to understanding the reactivity of these enzymes. Nuclear resonance vibrational spectroscopy (NRVS) is a recently developed synchrotron technique that is ideal for obtaining vibrational, and thus structural, information on Fe sites, as it gives complete information on all vibrational normal modes containing Fe displacement. In this study, we present NRVS data on BZDOp and assign its structure using these data coupled to experimentally calibrated density functional theory calculations. From this NRVS structure, we define the mechanism for the peroxide shunt reaction. The relevance of the peroxide shunt to the native FeII/O2 reaction is evaluated. For the native FeII/O2 reaction, an FeIII-superoxo intermediate is found to react directly with substrate. This process, while uphill thermodynamically, is found to be driven by the highly favorable thermodynamics of proton-coupled electron transfer with an electron provided by the Rieske [2Fe-2S] center at a later step in the reaction. These results offer important insight into the relative reactivities of FeIII-superoxo and FeIII-hydroperoxo species in nonheme Fe biochemistry.

Original languageEnglish
Pages (from-to)5544-5559
Number of pages16
JournalJournal of the American Chemical Society
Issue number16
Publication statusPublished - 2018 Apr 25


Dive into the research topics of 'NRVS Studies of the Peroxide Shunt Intermediate in a Rieske Dioxygenase and Its Relation to the Native FeII O2 Reaction'. Together they form a unique fingerprint.

Cite this