Ferric Superoxide and Ferric Hydroxide Are Used in the Catalytic Mechanism of Hydroxyethylphosphonate Dioxygenase: A Density Functional Theory Investigation.
Hydroxyethylphosphonate dioxygenase (HEPD) is a mononuclear nonheme iron enzyme that utilizes an O molecule to cleave a C—C bond in 2-hydroxyethylphosphonate and produce hydroxymethylphosphonate (HMP) and formic acid. Density functional theory calculations were performed on an enzyme active-site mod...
| Publicado en: | Journal of the American Chemical Society Vol. 132; no. 50; pp. 17901 - 17910 |
|---|---|
| Autores principales: | , |
| Formato: | Artículo |
| Publicado: |
American Chemical Society
12/22/2010
|
| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=57049043&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 57049043 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 12/22/2010 vid: 132 iid: 50 pid: 997 pub: American Chemical Society artinfo: ui: 57049043 10.1021/ja108174d ppf: 17901 ppct: 9 formats: tig: atl: Ferric Superoxide and Ferric Hydroxide Are Used in the Catalytic Mechanism of Hydroxyethylphosphonate Dioxygenase: A Density Functional Theory Investigation. aug: au: Hirao, Hajime Morokuma, Keiji affil: Fukui Institute for Fundamental Chemistry, Kyoto University, 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan Graduate School of System Informatics, Kobe University Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States su: Superoxides Hydroxides Enzymes Oxygenases Inositol sug: subj: Superoxides Hydroxides Enzymes Oxygenases Inositol ab: Hydroxyethylphosphonate dioxygenase (HEPD) is a mononuclear nonheme iron enzyme that utilizes an O molecule to cleave a C—C bond in 2-hydroxyethylphosphonate and produce hydroxymethylphosphonate (HMP) and formic acid. Density functional theory calculations were performed on an enzyme active-site model of HEPD to understand its catalytic mechanism. The reaction starts with H-abstraction from the C2 position of 2-HEP by a ferric superoxide-type (Fe(III)-OO) intermediate, in a similar manner to the H-abstraction in the reaction of the dinuclear iron enzyme myo-inositol oxygenase. The resultant Fe(II)-OOH intermediate may follow either a hydroperoxylation or hydroxylation pathway, the former process being energetically more favorable. In the hydroperoxylation pathway, a ferrous-alkylhydroperoxo intermediate is formed, and then its O—O bond is homolytically cleaved to yield a complex of ferric hydroxide with a gem-diol radical. Subsequent C—C bond cleavage within the gem-diol leads to formation of an R-CH• species and one of the two products (i.e., formic acid). The R-CH• then intramolecularly forms a C—O bond with the ferric hydroxide to provide the other product, HMP. The overall reaction pathway does not require the use of a high-valent ferryl intermediate but does require ferric superoxide and ferric hydroxide intermediates. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2010 holdings: @attributes: islocal: N |
|---|