View source for 4q5p


==Lysine-Ligated Yeast Iso-1 Cytochrome C==
<StructureSection load='4q5p' size='340' side='right'caption='[[4q5p]], [[Resolution|resolution]] 1.87&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4q5p]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4Q5P OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4Q5P FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.87&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4q5p FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4q5p OCA], [https://pdbe.org/4q5p PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4q5p RCSB], [https://www.ebi.ac.uk/pdbsum/4q5p PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4q5p ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CYC1_YEAST CYC1_YEAST] Electron carrier protein. The oxidized form of the cytochrome c heme group can accept an electron from the heme group of the cytochrome c1 subunit of cytochrome reductase. Cytochrome c then transfers this electron to the cytochrome oxidase complex, the final protein carrier in the mitochondrial electron-transport chain.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
It has been suggested that the alkaline form of cytochrome c (cyt c) regulates function of this protein as an electron carrier in oxidative phosphorylation and as a peroxidase that reacts with cardiolipin (CL) during apoptosis. In this form, Met80, the native ligand to the heme iron, is replaced by a Lys. While it has become clear that the structure of cyt c changes, the extent and sequence of conformational rearrangements associated with this ligand replacement remain a subject of debate. Herein we report a high-resolution crystal structure of a Lys73-ligated cyt c conformation that reveals intricate change in the heme environment upon this switch in the heme iron ligation. The structure is surprisingly compact, and the heme coordination loop refolds into a beta-hairpin with a turn formed by the highly conserved residues Pro76 and Gly77. Repositioning of residue 78 modifies the intraprotein hydrogen-bonding network and, together with adjustments of residues 52 and 74, increases the volume of the heme pocket to allow for insertion of one of the CL acyl moieties next to Asn52. Derivatization of Cys78 with maleimide creates a solution mimic of the Lys-ligated cyt c that has enhanced peroxidase activity, adding support for a role of the Lys-ligated cyt c in the apoptotic mechanism. Experiments with the heme peptide microperoxidase-8 and engineered model proteins provide a thermodynamic rationale for the switch to Lys ligation upon perturbations in the protein scaffold.

A Compact Structure of Cytochrome c Trapped in a Lysine-Ligated State: Loop Refolding and Functional Implications of a Conformational Switch.,Amacher JF, Zhong F, Lisi GP, Zhu MQ, Alden SL, Hoke KR, Madden DR, Pletneva EV J Am Chem Soc. 2015 Jun 3. PMID:26038984<ref>PMID:26038984</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 4q5p" style="background-color:#fffaf0;"></div>

==See Also==
*[[Cytochrome C 3D structures|Cytochrome C 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae]]
[[Category: Amacher JF]]
[[Category: Madden DR]]
[[Category: Pletneva EV]]
[[Category: Zhong F]]
[[Category: Zhu MQ]]