View source for 4dp1


==The 1.35 Angstrom crystal structure of reduced (CuI) poplar plastocyanin B at pH 4.0==
<StructureSection load='4dp1' size='340' side='right'caption='[[4dp1]], [[Resolution|resolution]] 1.35&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4dp1]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Populus_nigra Populus nigra]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4DP1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4DP1 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=CU1:COPPER+(I)+ION'>CU1</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=4dp1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4dp1 OCA], [https://pdbe.org/4dp1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4dp1 RCSB], [https://www.ebi.ac.uk/pdbsum/4dp1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4dp1 ProSAT]</span></td></tr>
</table>
== Function ==
[[https://www.uniprot.org/uniprot/PLAS2_POPNI PLAS2_POPNI]] Participates in electron transfer between P700 and the cytochrome b6-f complex in photosystem I.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Plastocyanin (PC) from poplar leaves is present in two isoforms, PCa and PCb, which differ in sequence by amino acid replacements at locations remote from the copper center and simultaneously act in the photosynthetic electron-transport chain. We describe ultra-high resolution structures of PCa and high-resolution structures of PCb, both under oxidizing and reducing conditions at pH 4, 6 and 8. The docking on cytochrome f and photosystem I, respectively, has been modeled for both isoforms. PCa and PCb exhibit closely similar overall and active-site structures, except for a difference in the relative orientation of the acidic patches. The isoforms exhibit substantial differences in the dependence of the reduced (Cu(I)) geometry on pH. In PCa, the decrease in pH causes a gradual dissociation of His87 from Cu(I) at low pH, probably adopting a neutral tautomeric state. In PCb, the histidine remains covalently bound to Cu(I) and may adopt a doubly protonated state at low pH. The fact that both isoforms have similar although not identical functions in photosynthetic electron flows suggests that the His87 imidazole does not play a crucial role for the pathway of electron transport from cytochrome f to oxidized PC.

Structural comparison of the poplar plastocyanin isoforms PCa and PCb sheds new light on the role of the copper site geometry in interactions with redox partners in oxygenic photosynthesis.,Kachalova GS, Shosheva AC, Bourenkov GP, Donchev AA, Dimitrov MI, Bartunik HD J Inorg Biochem. 2012 Oct;115:174-81. doi: 10.1016/j.jinorgbio.2012.07.015. Epub , 2012 Jul 20. PMID:22883960<ref>PMID:22883960</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4dp1" style="background-color:#fffaf0;"></div>

==See Also==
*[[Plastocyanin 3D structures|Plastocyanin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Populus nigra]]
[[Category: Bartunik HD]]
[[Category: Bourenkov GP]]
[[Category: Dimitrov MI]]
[[Category: Donchev AA]]
[[Category: Kachalova GS]]
[[Category: Shosheva AH]]