View source for 2yl7

==CYTOCHROME C PRIME FROM ALCALIGENES XYLOSOXIDANS: AS ISOLATED L16G VARIANT AT 0.9 A RESOLUTION - RESTRAINT REFINEMENT==
<StructureSection load='2yl7' size='340' side='right' caption='[[2yl7]], [[Resolution|resolution]] 0.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2yl7]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Achromobacter_xylosoxidans Achromobacter xylosoxidans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2YL7 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2YL7 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CMO:CARBON+MONOXIDE'>CMO</scene>, <scene name='pdbligand=HEC:HEME+C'>HEC</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2xm0|2xm0]], [[2xlh|2xlh]], [[1cgo|1cgo]], [[2ykz|2ykz]], [[2xm4|2xm4]], [[1e86|1e86]], [[2xl6|2xl6]], [[2yl0|2yl0]], [[1e85|1e85]], [[1cgn|1cgn]], [[2xlm|2xlm]], [[2yl1|2yl1]], [[2xld|2xld]], [[2xle|2xle]], [[1e83|1e83]], [[2xl8|2xl8]], [[2xlw|2xlw]], [[1e84|1e84]], [[2xlv|2xlv]], [[2xlo|2xlo]], [[2yl3|2yl3]]</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2yl7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2yl7 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2yl7 RCSB], [http://www.ebi.ac.uk/pdbsum/2yl7 PDBsum]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/CYCP_ALCXX CYCP_ALCXX]] Cytochrome c' is the most widely occurring bacterial c-type cytochrome. Cytochromes c' are high-spin proteins and the heme has no sixth ligand. Their exact function is not known. 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Carbon monoxide (CO) is a product of haem metabolism and organisms must evolve strategies to prevent endogenous CO poisoning of haemoproteins. We show that energy costs associated with conformational changes play a key role in preventing irreversible CO binding. AxCYTcp is a member of a family of haem proteins that form stable 5c-NO and 6c-CO complexes but do not form O(2) complexes. Structure of the AxCYTcp-CO complex at 1.25 A resolution shows that CO binds in two conformations moderated by the extent of displacement of the distal residue Leu16 toward the haem 7-propionate. The presence of two CO conformations is confirmed by cryogenic resonance Raman data. The preferred linear Fe-C-O arrangement (170 +/- 8 degrees ) is accompanied by a flip of the propionate from the distal to proximal face of the haem. In the second conformation, the Fe-C-O unit is bent (158 +/- 8 degrees ) with no flip of propionate. The energetic cost of the CO-induced Leu-propionate movements is reflected in a 600 mV (57.9 kJmol(-1)) decrease in haem potential, a value in good agreement with density functional theory calculations. Substitution of Leu by Ala or Gly (structures determined at 1.03 and 1.04 A resolutions) resulted in a haem site that binds CO in the linear mode only and where no significant change in redox potential is observed. Remarkably, these variants were isolated as ferrous 6c-CO complexes, attributable to the observed eight orders of magnitude increase in affinity for CO, including an approximately 10,000-fold decrease in the rate of dissociation. These new findings have wide implications for preventing CO poisoning of gas-binding haem proteins.

Carbon monoxide poisoning is prevented by the energy costs of conformational changes in gas-binding haemproteins.,Antonyuk SV, Rustage N, Petersen CA, Arnst JL, Heyes DJ, Sharma R, Berry NG, Scrutton NS, Eady RR, Andrew CR, Hasnain SS Proc Natl Acad Sci U S A. 2011 Sep 20;108(38):15780-5. Epub 2011 Sep 7. PMID:21900609<ref>PMID:21900609</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>

==See Also==
*[[Cytochrome c|Cytochrome c]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Achromobacter xylosoxidans]]
[[Category: Antonyuk, S V]]
[[Category: Eady, R R]]
[[Category: Hasnain, S S]]
[[Category: Rustage, N]]
[[Category: 4-helix bundle]]
[[Category: Electron transport]]
[[Category: Haemoprotein]]