2ij3: Difference between revisions
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[[Image: | ==Structure of the A264H mutant of cytochrome P450 BM3== | ||
<StructureSection load='2ij3' size='340' side='right' caption='[[2ij3]], [[Resolution|resolution]] 1.90Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2ij3]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Bacillus_megaterium Bacillus megaterium]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2IJ3 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2IJ3 FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene><br> | |||
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2ij2|2ij2]], [[2ij4|2ij4]], [[2ij5|2ij5]], [[2ij7|2ij7]], [[1jpz|1jpz]], [[1bu7|1bu7]], [[1smi|1smi]]</td></tr> | |||
<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">CYP102A1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1404 Bacillus megaterium])</td></tr> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Unspecific_monooxygenase Unspecific monooxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.14.14.1 1.14.14.1] </span></td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2ij3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ij3 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2ij3 RCSB], [http://www.ebi.ac.uk/pdbsum/2ij3 PDBsum]</span></td></tr> | |||
<table> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ij/2ij3_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Two novel P450 heme iron ligand sets were generated by directed mutagenesis of the flavocytochrome P450 BM3 heme domain. The A264H and A264K variants produce Cys-Fe-His and Cys-Fe-Lys axial ligand sets, which were validated structurally and characterized by spectroscopic analysis. EPR and magnetic circular dichroism (MCD) provided fingerprints defining these P450 ligand sets. Near IR MCD spectra identified ferric low spin charge-transfer bands diagnostic of the novel ligands. For the A264K mutant, this is the first report of a Cys-Fe-Lys near-IR MCD band. Crystal structure determination showed that substrate-free A264H and A264K proteins crystallize in distinct conformations, as observed previously in substrate-free and fatty acid-bound wild-type P450 forms, respectively. This, in turn, likely reflects the positioning of the I alpha helix section of the protein that is required for optimal configuration of the ligands to the heme iron. One of the monomers in the asymmetric unit of the A264H crystals was in a novel conformation with a more open substrate access route to the active site. The same species was isolated for the wildtype heme domain and represents a novel conformational state of BM3 (termed SF2). The "locking" of these distinct conformations is evident from the fact that the endogenous ligands cannot be displaced by substrate or exogenous ligands. The consequent reduction of heme domain conformational heterogeneity will be important in attempts to determine atomic structure of the full-length, multidomain flavocytochrome, and thus to understand in atomic detail interactions between its heme and reductase domains. | |||
Structural and spectroscopic characterization of P450 BM3 mutants with unprecedented P450 heme iron ligand sets. New heme ligation states influence conformational equilibria in P450 BM3.,Girvan HM, Seward HE, Toogood HS, Cheesman MR, Leys D, Munro AW J Biol Chem. 2007 Jan 5;282(1):564-72. Epub 2006 Oct 31. PMID:17077084<ref>PMID:17077084</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[Cytochrome P450|Cytochrome P450]] | *[[Cytochrome P450|Cytochrome P450]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Bacillus megaterium]] | [[Category: Bacillus megaterium]] | ||
[[Category: Unspecific monooxygenase]] | [[Category: Unspecific monooxygenase]] | ||
Revision as of 08:24, 29 September 2014
Structure of the A264H mutant of cytochrome P450 BM3Structure of the A264H mutant of cytochrome P450 BM3
Structural highlights
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 PubMedTwo novel P450 heme iron ligand sets were generated by directed mutagenesis of the flavocytochrome P450 BM3 heme domain. The A264H and A264K variants produce Cys-Fe-His and Cys-Fe-Lys axial ligand sets, which were validated structurally and characterized by spectroscopic analysis. EPR and magnetic circular dichroism (MCD) provided fingerprints defining these P450 ligand sets. Near IR MCD spectra identified ferric low spin charge-transfer bands diagnostic of the novel ligands. For the A264K mutant, this is the first report of a Cys-Fe-Lys near-IR MCD band. Crystal structure determination showed that substrate-free A264H and A264K proteins crystallize in distinct conformations, as observed previously in substrate-free and fatty acid-bound wild-type P450 forms, respectively. This, in turn, likely reflects the positioning of the I alpha helix section of the protein that is required for optimal configuration of the ligands to the heme iron. One of the monomers in the asymmetric unit of the A264H crystals was in a novel conformation with a more open substrate access route to the active site. The same species was isolated for the wildtype heme domain and represents a novel conformational state of BM3 (termed SF2). The "locking" of these distinct conformations is evident from the fact that the endogenous ligands cannot be displaced by substrate or exogenous ligands. The consequent reduction of heme domain conformational heterogeneity will be important in attempts to determine atomic structure of the full-length, multidomain flavocytochrome, and thus to understand in atomic detail interactions between its heme and reductase domains. Structural and spectroscopic characterization of P450 BM3 mutants with unprecedented P450 heme iron ligand sets. New heme ligation states influence conformational equilibria in P450 BM3.,Girvan HM, Seward HE, Toogood HS, Cheesman MR, Leys D, Munro AW J Biol Chem. 2007 Jan 5;282(1):564-72. Epub 2006 Oct 31. PMID:17077084[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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