3ekd | pdb_00003ekd

Crystal structure of the A264M heme domain of cytochrome P450 BM3

spinqualitylabelsall models 3ekd, resolution 2.50Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3ekd is a 2 chain structure with sequence from Bacillus megaterium. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: HEM, PAM Related: 3ekf, 3ekb, 1smi, 2ij3, 2ij4 Gene: CYP102A1, cyp102 (Bacillus megaterium) Activity: Unspecific monooxygenase, with EC number 1.14.14.1 Resources: FirstGlance, OCA, RCSB, PDBsum Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Bacillus megaterium flavocytochrome P450 BM3 is a catalytically self-sufficient fatty acid hydroxylase formed by fusion of soluble NADPH-cytochrome P450 reductase and P450 domains. Selected mutations at residue 264 in the haem (P450) domain of the enzyme lead to novel amino acid sixth (distal) co-ordination ligands to the haem iron. The catalytic, spectroscopic and thermodynamic properties of the A264M, A264Q and A264C variants were determined in both the intact flavocytochromes and haem domains of P450 BM3. Crystal structures of the mutant haem domains demonstrate axial ligation of P450 haem iron by methionine and glutamine ligands trans to the cysteine thiolate, creating novel haem iron ligand sets in the A264M/Q variants. In contrast, the crystal structure of the A264C variant reveals no direct interaction between the introduced cysteine side chain and the haem, although EPR data indicate Cys(264) interactions with haem iron in solution. The A264M haem potential is elevated by comparison with wild-type haem domain, and substrate binding to the A264Q haem domain results in a approximately 360 mV increase in potential. All mutant haem domains occupy the conformation adopted by the substrate-bound form of wild-type BM3, despite the absence of added substrate. The A264M mutant (which has higher dodecanoate affinity than wild-type BM3) co-purifies with a structurally resolved lipid. These data demonstrate that a single mutation at Ala(264) is enough to perturb the conformational equilibrium between substrate-free and substrate-bound P450 BM3, and provide firm structural and spectroscopic data for novel haem iron ligand sets unprecedented in nature. Novel haem co-ordination variants of flavocytochrome P450BM3.,Girvan HM, Toogood HS, Littleford RE, Seward HE, Smith WE, Ekanem IS, Leys D, Cheesman MR, Munro AW Biochem J. 2009 Jan 1;417(1):65-76. PMID:18721129 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Cytochrome P450 Flavocytochrome

Proteopedia Page Contributors and Editors (what is this?)

OCA