The Structures and Electronic Configuration of Compound I Intermediates of Helicobacter pylori and Penicillium vitale Catalases Determined by X-ray Crystallography and QM/MM Density Functional Theory Calculations.
The structures of Helicobacter pylori (HPC) and Penicillium vitale (PVC) catalases, each with two subunits in the crystal asymmetric unit, oxidized with peroxoacetic acid are reported at 1.8 and 1.7 Å resolution, respectively. Despite the similar oxidation conditions employed, the iron-oxygen coordi...
| Publicado en: | Journal of the American Chemical Society Vol. 129; no. 14; pp. 4193 - 4206 |
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| Autores principales: | , , , , , , , |
| Formato: | Artículo |
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American Chemical Society
4/11/2007
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| 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=24824530&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 24824530 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: 4/11/2007 vid: 129 iid: 14 pid: 997 pub: American Chemical Society artinfo: ui: 24824530 10.1021/ja063660y ppf: 4193 ppct: 13 formats: tig: atl: The Structures and Electronic Configuration of Compound I Intermediates of Helicobacter pylori and Penicillium vitale Catalases Determined by X-ray Crystallography and QM/MM Density Functional Theory Calculations. aug: au: Alfonso-Prieto, Mercedes Borovik, Anton Carpena, Xavier Murshudov, Garib Melik-Adamyan, William Fita, Ignacio Rovira, Carme Loewen, Peter C. affil: Centre especial de Recerca en Química Teòrica, Parc Científic de Barcelona, Josep Samitier 1-5, 08028 Barcelona, Spain Institute of Crystallography of Russian Academy of Sciences, Lenisky Prospekt 59, 119333 Moscow, Russia Institut de Biologia Molecular de Barcelona-CSIC, Parc Científic de Barcelona, Josep Samitier 1-5, 08028 Barcelona, Spain Institut de Recerca Biomèdica, Parc Científic de Barcelona, Josep Samitier 1-5, 08028 Barcelona, Spain Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5YW, England Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08018 Barcelona, Spain Department of Microbiology, University of Manitoba, Winnipeg, Canada MB R3T 2N2 su: Electronic structure Helicobacter pylori Penicillium Quantum theory X-ray crystallography Density functionals Physical vapor deposition sug: subj: Electronic structure Helicobacter pylori Penicillium Quantum theory X-ray crystallography Density functionals Physical vapor deposition ab: The structures of Helicobacter pylori (HPC) and Penicillium vitale (PVC) catalases, each with two subunits in the crystal asymmetric unit, oxidized with peroxoacetic acid are reported at 1.8 and 1.7 Å resolution, respectively. Despite the similar oxidation conditions employed, the iron-oxygen coordination length is 1.72 Å for PVC, close to what is expected for a FeO double bond, and 1.80 and 1.85 Å for HPC, suggestive of a FeO single bond. The structure and electronic configuration of the oxoferryl heme and immediate protein environment is investigated further by QM/MM density functional theory calculations. Four different active site electronic configurations are considered, PoṙFeO, PoṙFeO⋯HisH, PoṙFeOH and PorFeOH (a protein radical is assumed in the latter configuration). The electronic structure of the primary oxidized species, PoṙFeO, differs qualitatively between HPC and PVC with an A-like porphyrin radical delocalized on the porphyrin in HPC and a mixed A-like ‘fluctuating’ radical partially delocalized over the essential distal histidine, the porphyrin, and, to a lesser extent, the proximal tyrosine residue. This difference is rationalized in terms of HPC containing heme b and PVC containing heme d. It is concluded that compound I of PVC contains an oxoferryl PoṙFeO species with partial protonation of the distal histidine and compound I of HPC contains a hydroxoferryl PorFeOH with the second oxidation equivalent delocalized as a protein radical. The findings support the idea that there is a relation between radical migration to the protein and protonation of the oxoferryl bond in catalase. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2007 holdings: @attributes: islocal: N |
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