1zby
From Proteopedia
(New page: 200px<br /><applet load="1zby" size="450" color="white" frame="true" align="right" spinBox="true" caption="1zby, resolution 1.20Å" /> '''High-Resolution Crys...) |
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| - | [[Image:1zby.gif|left|200px]]<br /><applet load="1zby" size=" | + | [[Image:1zby.gif|left|200px]]<br /><applet load="1zby" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1zby, resolution 1.20Å" /> | caption="1zby, resolution 1.20Å" /> | ||
'''High-Resolution Crystal Structure of Native (Resting) Cytochrome c Peroxidase (CcP)'''<br /> | '''High-Resolution Crystal Structure of Native (Resting) Cytochrome c Peroxidase (CcP)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Cytochrome c peroxidase (CCP) is a 32.5 kDa mitochondrial intermembrane | + | Cytochrome c peroxidase (CCP) is a 32.5 kDa mitochondrial intermembrane space heme peroxidase from Saccharomyces cerevisiae that reduces H(2)O(2) to 2H(2)O by oxidizing two molecules of cytochrome c (cyt c). Here we compare the 1.2 A native structure (CCP) with the 1.3 A structure of its stable oxidized reaction intermediate, Compound I (CCP1). In addition, crystals were analyzed by UV-vis absorption and electron paramagnetic resonance spectroscopies before and after data collection to determine the state of the Fe(IV) center and the cationic Trp191 radical formed in Compound I. The results show that X-ray exposure does not lead to reduction of Fe(IV) and only partial reduction of the Trp radical. A comparison of the two structures reveals subtle but important conformational changes that aid in the stabilization of the Trp191 cationic radical in Compound I. The higher-resolution data also enable a more accurate determination of changes in heme parameters. Most importantly, when one goes from resting state Fe(III) to Compound I, the His-Fe bond distance increases, the iron moves into the porphyrin plane leading to shorter pyrrole N-Fe bonds, and the Fe(IV)-O bond distance is 1.87 A, suggesting a single Fe(IV)-O bond and not the generally accepted double bond. |
==About this Structure== | ==About this Structure== | ||
| - | 1ZBY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with HEM as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Cytochrome-c_peroxidase Cytochrome-c peroxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.11.1.5 1.11.1.5] Full crystallographic information is available from [http:// | + | 1ZBY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Cytochrome-c_peroxidase Cytochrome-c peroxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.11.1.5 1.11.1.5] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ZBY OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Bhaskar, B.]] | [[Category: Bhaskar, B.]] | ||
| - | [[Category: Bonagura, C | + | [[Category: Bonagura, C A.]] |
| - | [[Category: Goodin, D | + | [[Category: Goodin, D B.]] |
[[Category: Li, H.]] | [[Category: Li, H.]] | ||
| - | [[Category: McRee, D | + | [[Category: McRee, D E.]] |
| - | [[Category: Poulos, T | + | [[Category: Poulos, T L.]] |
[[Category: Shimizu, H.]] | [[Category: Shimizu, H.]] | ||
[[Category: Sundaramoorthy, M.]] | [[Category: Sundaramoorthy, M.]] | ||
| Line 29: | Line 29: | ||
[[Category: trp-cation radical]] | [[Category: trp-cation radical]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:14:04 2008'' |
Revision as of 14:14, 21 February 2008
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High-Resolution Crystal Structure of Native (Resting) Cytochrome c Peroxidase (CcP)
Overview
Cytochrome c peroxidase (CCP) is a 32.5 kDa mitochondrial intermembrane space heme peroxidase from Saccharomyces cerevisiae that reduces H(2)O(2) to 2H(2)O by oxidizing two molecules of cytochrome c (cyt c). Here we compare the 1.2 A native structure (CCP) with the 1.3 A structure of its stable oxidized reaction intermediate, Compound I (CCP1). In addition, crystals were analyzed by UV-vis absorption and electron paramagnetic resonance spectroscopies before and after data collection to determine the state of the Fe(IV) center and the cationic Trp191 radical formed in Compound I. The results show that X-ray exposure does not lead to reduction of Fe(IV) and only partial reduction of the Trp radical. A comparison of the two structures reveals subtle but important conformational changes that aid in the stabilization of the Trp191 cationic radical in Compound I. The higher-resolution data also enable a more accurate determination of changes in heme parameters. Most importantly, when one goes from resting state Fe(III) to Compound I, the His-Fe bond distance increases, the iron moves into the porphyrin plane leading to shorter pyrrole N-Fe bonds, and the Fe(IV)-O bond distance is 1.87 A, suggesting a single Fe(IV)-O bond and not the generally accepted double bond.
About this Structure
1ZBY is a Single protein structure of sequence from Saccharomyces cerevisiae with as ligand. Active as Cytochrome-c peroxidase, with EC number 1.11.1.5 Full crystallographic information is available from OCA.
Reference
High-resolution crystal structures and spectroscopy of native and compound I cytochrome c peroxidase., Bonagura CA, Bhaskar B, Shimizu H, Li H, Sundaramoorthy M, McRee DE, Goodin DB, Poulos TL, Biochemistry. 2003 May 20;42(19):5600-8. PMID:12741816
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