View source for 5b82


==Crystal structure of the cyanobacterial heme-protein Tll0287==
<StructureSection load='5b82' size='340' side='right'caption='[[5b82]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5b82]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermosynechococcus_vestitus_BP-1 Thermosynechococcus vestitus BP-1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5B82 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5B82 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]] 2&#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=HEC:HEME+C'>HEC</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=5b82 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5b82 OCA], [https://pdbe.org/5b82 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5b82 RCSB], [https://www.ebi.ac.uk/pdbsum/5b82 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5b82 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q8DM36_THEVB Q8DM36_THEVB] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Photosystem II catalyzes light-induced water oxidation leading to the generation of dioxygen indispensable for sustaining aerobic life on Earth. The Photosystem II reaction center is composed of D1 and D2 proteins encoded by psbA and psbD genes, respectively. In cyanobacteria, different psbA genes are present in the genome. The thermophilic cyanobacterium Thermosynechococcus elongatus contains three psbA genes: psbA1, psbA2, and psbA3, and a new c-type heme protein, Tll0287, was found to be expressed in a strain expressing the psbA2 gene only, but the structure and function of Tll0287 are unknown. Here we solved the crystal structure of Tll0287 at a 2.0 A resolution. The overall structure of Tll0287 was found to be similar to some kinases and sensor proteins with a Per-Arnt-Sim-like domain rather than to other c-type cytochromes. The fifth and sixth axial ligands for the heme were Cys and His, instead of the His/Met or His/His ligand pairs observed for most of the c-type hemes. The redox potential, E(1/2), of Tll0287 was -255 +/- 20 mV versus normal hydrogen electrode at pH values above 7.5. Below this pH value, the E(1/2) increased by approximately 57 mV/pH unit at 15 degrees C, suggesting the involvement of a protonatable group with a pKred = 7.2 +/- 0.3. Possible functions of Tll0287 as a redox sensor under microaerobic conditions or a cytochrome subunit of an H2S-oxidizing system are discussed in view of the environmental conditions in which psbA2 is expressed, as well as phylogenetic analysis, structural, and sequence homologies.

Crystal structure and redox properties of a novel cyanobacterial heme protein with a His/Cys heme axial ligation and a Per-Arnt-Sim (PAS)-like domain.,Motomura T, Suga M, Hienerwadel R, Nakagawa A, Lai TL, Nitschke W, Kuma T, Sugiura M, Boussac A, Shen JR J Biol Chem. 2017 Jun 9;292(23):9599-9612. doi: 10.1074/jbc.M116.746263. Epub, 2017 Apr 20. PMID:28428249<ref>PMID:28428249</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5b82" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Thermosynechococcus vestitus BP-1]]
[[Category: Motomura T]]
[[Category: Shen JR]]
[[Category: Suga M]]