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1qks
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Cytochrome cd1-nitrite reductase is a bifunctional enzyme that catalyzes | + | Cytochrome cd1-nitrite reductase is a bifunctional enzyme that catalyzes the one-electron reduction of nitrite to nitric oxide and the four-electron reduction of oxygen to water. The 1.55 A crystal structure of the dimeric enzyme from Thiosphaera pantotropha is reported here. The protein was sequenced from the X-ray structure. Each subunit contains a covalent c heme with two axial His ligands (His-17, His-69) and a unique noncovalent d1 heme ligated by Tyr-25 and His-200. The d1 heme is the mononuclear iron center where both oxygen and nitrite reduction take place. The two types of heme are located in separate domains whose arrangement suggests a mechanism requiring domain movement during catalysis. |
==About this Structure== | ==About this Structure== | ||
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[[Category: periplasmic]] | [[Category: periplasmic]] | ||
| - | ''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 14:40:44 2008'' |
Revision as of 12:40, 21 February 2008
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CYTOCHROME CD1 NITRITE REDUCTASE, OXIDISED FORM
Overview
Cytochrome cd1-nitrite reductase is a bifunctional enzyme that catalyzes the one-electron reduction of nitrite to nitric oxide and the four-electron reduction of oxygen to water. The 1.55 A crystal structure of the dimeric enzyme from Thiosphaera pantotropha is reported here. The protein was sequenced from the X-ray structure. Each subunit contains a covalent c heme with two axial His ligands (His-17, His-69) and a unique noncovalent d1 heme ligated by Tyr-25 and His-200. The d1 heme is the mononuclear iron center where both oxygen and nitrite reduction take place. The two types of heme are located in separate domains whose arrangement suggests a mechanism requiring domain movement during catalysis.
About this Structure
1QKS is a Single protein structure of sequence from Paracoccus denitrificans with , , and as ligands. Known structural/functional Sites: , , and . Full crystallographic information is available from OCA.
Reference
The anatomy of a bifunctional enzyme: structural basis for reduction of oxygen to water and synthesis of nitric oxide by cytochrome cd1., Fulop V, Moir JW, Ferguson SJ, Hajdu J, Cell. 1995 May 5;81(3):369-77. PMID:7736589
Page seeded by OCA on Thu Feb 21 14:40:44 2008
Categories: Paracoccus denitrificans | Single protein | Fulop, V. | DHE | GOL | HEC | SO4 | Denitrification | Electron transport | Enzyme | Nitrite reductase | Oxidoreductase | Periplasmic
