View source for 1xg0


==High resolution crystal structure of phycoerythrin 545 from the marine cryptophyte rhodomonas CS24==
<StructureSection load='1xg0' size='340' side='right'caption='[[1xg0]], [[Resolution|resolution]] 0.97&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1xg0]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Rhodomonas_sp._CS24 Rhodomonas sp. CS24]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XG0 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1XG0 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]] 0.97&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=DBV:15,16-DIHYDROBILIVERDIN'>DBV</scene>, <scene name='pdbligand=LYZ:5-HYDROXYLYSINE'>LYZ</scene>, <scene name='pdbligand=MEN:N-METHYL+ASPARAGINE'>MEN</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PEB:PHYCOERYTHROBILIN'>PEB</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=1xg0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xg0 OCA], [https://pdbe.org/1xg0 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1xg0 RCSB], [https://www.ebi.ac.uk/pdbsum/1xg0 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1xg0 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PHE3_RHDS2 PHE3_RHDS2] Light-harvesting photosynthetic tetrapyrrole chromophore-protein from the phycobiliprotein complex.
== 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/xg/1xg0_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/main_output.php?pdb_ID=1xg0 ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
Cryptophyte algae differ from cyanobacteria and red algae in the architecture of their photosynthetic light harvesting systems, even though all three are evolutionarily related. Central to cryptophyte light harvesting is the soluble antenna protein phycoerythrin 545 (PE545). The ultrahigh resolution crystal structure of PE545, isolated from a unicellular cryptophyte Rhodomonas CS24, is reported at both 1.1A and 0.97A resolution, revealing details of the conformation and environments of the chromophores. Absorption, emission and polarized steady state spectroscopy (298K, 77K), as well as ultrafast (20fs time resolution) measurements of population dynamics are reported. Coupled with complementary quantum chemical calculations of electronic transitions of the bilins, these enable assignment of spectral absorption characteristics to each chromophore in the structure. Spectral differences between the tetrapyrrole pigments due to chemical differences between bilins, as well as their binding and interaction with the local protein environment are described. Based on these assignments, and considering customized optical properties such as strong coupling, a model for light harvesting by PE545 is developed which explains the fast, directional harvesting of excitation energy. The excitation energy is funnelled from four peripheral pigments (beta158,beta82) into a central chromophore dimer (beta50/beta61) in approximately 1ps. Those chromophores, in turn, transfer the excitation energy to the red absorbing molecules located at the periphery of the complex in approximately 4ps. A final resonance energy transfer step sensitizes just one of the alpha19 bilins on a time scale of 22ps. Furthermore, it is concluded that binding of PE545 to the thylakoid membrane is not essential for efficient energy transfer to the integral membrane chlorophyll a-containing complexes associated with PS-II.

Developing a structure-function model for the cryptophyte phycoerythrin 545 using ultrahigh resolution crystallography and ultrafast laser spectroscopy.,Doust AB, Marai CN, Harrop SJ, Wilk KE, Curmi PM, Scholes GD J Mol Biol. 2004 Nov 12;344(1):135-53. PMID:15504407<ref>PMID:15504407</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1xg0" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Rhodomonas sp. CS24]]
[[Category: Curmi PMG]]
[[Category: Doust AB]]
[[Category: Harrop SJ]]
[[Category: Marai CNJ]]
[[Category: Scholes GD]]
[[Category: Wilk KE]]