3cpp
From Proteopedia
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, resolution 1.9Å | |||||||
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Ligands: | , and | ||||||
Activity: | Camphor 5-monooxygenase, with EC number 1.14.15.1 | ||||||
Coordinates: | save as pdb, mmCIF, xml |
CRYSTAL STRUCTURE OF THE CARBON MONOXY-SUBSTRATE-CYTOCHROME P450-CAM TERNARY COMPLEX
Overview
The crystal structure of the ternary complex formed between carbon monoxide (CO), camphor, and ferrous cytochrome P-450CAM has been refined to an R value of 17.9% at 1.9-A resolution. To accommodate the CO molecule, the substrate, camphor, moves about 0.8 A while at the same time remaining in nonbonded contact with CO. The average temperature factor of the camphor atoms is about 50% higher in the CO complex, suggesting that the camphor is more loosely bound in this ternary complex. The Fe-C-O angle is about 166 degrees, and thus, CO appears to be bent from the heme normal, as it is in various CO-globin complexes, due to steric interactions with active site groups. The oxygen atom of the CO molecule is nestled into a groove formed by an unusual helical hydrogen bond in the distal helix between the highly conserved Thr 252 and Gly 248 residues. In the transition from the ferric camphor-bound binary complex to the ferrous CO-camphor-bound ternary complex, the heme iron atom moves into the plane defined by the pyrrole nitrogens by about 0.41 A. Although the axial Cys ligand also moves toward the heme, the S-Fe bond stretches from about 2.20 A in the absence of CO to about 2.41 A once CO has bound.
About this Structure
3CPP is a Single protein structure of sequence from Pseudomonas putida. The following page contains interesting information on the relation of 3CPP with [Cytochrome p450]. Full crystallographic information is available from OCA.
Reference
Crystal structure of the carbon monoxide-substrate-cytochrome P-450CAM ternary complex., Raag R, Poulos TL, Biochemistry. 1989 Sep 19;28(19):7586-92. PMID:2611203
Page seeded by OCA on Thu Mar 20 19:04:11 2008