2v1k
From Proteopedia
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==Overview== | ==Overview== | ||
| - | High resolution crystal structures of myoglobin in the pH range 5.2-8.7 | + | High resolution crystal structures of myoglobin in the pH range 5.2-8.7 have been used as models for the peroxide-derived compound II intermediates in heme peroxidases and oxygenases. The observed Fe-O bond length (1.86-1.90 A) is consistent with that of a single bond. The compound II state of myoglobin in crystals was controlled by single-crystal microspectrophotometry before and after synchrotron data collection. We observe some radiation-induced changes in both compound II (resulting in intermediate H) and in the resting ferric state of myoglobin. These radiation-induced states are quite unstable, and compound II and ferric myoglobin are immediately regenerated through a short heating above the glass transition temperature (<1 s) of the crystals. It is unclear how this influences our compound II structures compared with the unaffected compound II, but some crystallographic data suggest that the influence on the Fe-O bond distance is minimal. Based on our crystallographic and spectroscopic data we suggest that for myoglobin the compound II intermediate consists of an Fe(IV)-O species with a single bond. The presence of Fe(IV) is indicated by a small isomer shift of delta = 0.07 mm/s from Mossbauer spectroscopy. Earlier quantum refinements (crystallographic refinement where the molecular-mechanics potential is replaced by a quantum chemical calculation) and density functional theory calculations suggest that this intermediate H species is protonated. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Equus caballus]] | [[Category: Equus caballus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Andersson, K | + | [[Category: Andersson, K K.]] |
| - | [[Category: Gorbitz, C | + | [[Category: Gorbitz, C H.]] |
| - | [[Category: Hersleth, H | + | [[Category: Hersleth, H P.]] |
[[Category: GOL]] | [[Category: GOL]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
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[[Category: transport]] | [[Category: transport]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:52:28 2008'' |
Revision as of 16:52, 21 February 2008
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CRYSTAL STRUCTURE OF FERROUS DEOXYMYOGLOBIN AT PH 6.8
Overview
High resolution crystal structures of myoglobin in the pH range 5.2-8.7 have been used as models for the peroxide-derived compound II intermediates in heme peroxidases and oxygenases. The observed Fe-O bond length (1.86-1.90 A) is consistent with that of a single bond. The compound II state of myoglobin in crystals was controlled by single-crystal microspectrophotometry before and after synchrotron data collection. We observe some radiation-induced changes in both compound II (resulting in intermediate H) and in the resting ferric state of myoglobin. These radiation-induced states are quite unstable, and compound II and ferric myoglobin are immediately regenerated through a short heating above the glass transition temperature (<1 s) of the crystals. It is unclear how this influences our compound II structures compared with the unaffected compound II, but some crystallographic data suggest that the influence on the Fe-O bond distance is minimal. Based on our crystallographic and spectroscopic data we suggest that for myoglobin the compound II intermediate consists of an Fe(IV)-O species with a single bond. The presence of Fe(IV) is indicated by a small isomer shift of delta = 0.07 mm/s from Mossbauer spectroscopy. Earlier quantum refinements (crystallographic refinement where the molecular-mechanics potential is replaced by a quantum chemical calculation) and density functional theory calculations suggest that this intermediate H species is protonated.
About this Structure
2V1K is a Single protein structure of sequence from Equus caballus with , and as ligands. Known structural/functional Sites: , , , and . Full crystallographic information is available from OCA.
Reference
Crystallographic and spectroscopic studies of peroxide-derived myoglobin compound II and occurrence of protonated FeIV O., Hersleth HP, Uchida T, Rohr AK, Teschner T, Schunemann V, Kitagawa T, Trautwein AX, Gorbitz CH, Andersson KK, J Biol Chem. 2007 Aug 10;282(32):23372-86. Epub 2007 Jun 12. PMID:17565988
Page seeded by OCA on Thu Feb 21 18:52:28 2008
Categories: Equus caballus | Single protein | Andersson, K K. | Gorbitz, C H. | Hersleth, H P. | GOL | HEM | SO4 | Haem | Heme | Iron | Metal-binding | Monooxygenase | Muscle protein | Oxygen activation | Oxygen transport | Transport
