View source for 2xvz


==Cobalt chelatase CbiK (periplasmatic) from Desulvobrio vulgaris Hildenborough (co-crystallized with cobalt)==
<StructureSection load='2xvz' size='340' side='right'caption='[[2xvz]], [[Resolution|resolution]] 2.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2xvz]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Desulfovibrio_vulgaris_str._Hildenborough Desulfovibrio vulgaris str. Hildenborough]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2XVZ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2XVZ 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]] 2.4&#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=CO:COBALT+(II)+ION'>CO</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PER:PEROXIDE+ION'>PER</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=2xvz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2xvz OCA], [https://pdbe.org/2xvz PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2xvz RCSB], [https://www.ebi.ac.uk/pdbsum/2xvz PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2xvz ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CBIKP_NITV2 CBIKP_NITV2] Catalyzes the insertion of Co(2+) into sirohydrochlorin. To a lesser extent, is also able to insert Fe(2+) into sirohydrochlorin, yielding siroheme. Its periplasmic location means that it cannot participate in cobalamin biosynthesis and its genomic environment suggests it is likely to be associated with a heme or metal transport system.<ref>PMID:18457416</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The class II chelatases associated with heme, siroheme, and cobalamin biosynthesis are structurally related enzymes that insert a specific metal ion (Fe(2+) or Co(2+)) into the center of a modified tetrapyrrole (protoporphyrin or sirohydrochlorin). The structures of two related class II enzymes, CbiX(S) from Archaeoglobus fulgidus and CbiK from Salmonella enterica, that are responsible for the insertion of cobalt along the cobalamin biosynthesis pathway are presented in complex with their metallated product. A further structure of a CbiK from Desulfovibrio vulgaris Hildenborough reveals how cobalt is bound at the active site. The crystal structures show that the binding of sirohydrochlorin is distinctly different to porphyrin binding in the protoporphyrin ferrochelatases and provide a molecular overview of the mechanism of chelation. The structures also give insights into the evolution of chelatase form and function. Finally, the structure of a periplasmic form of Desulfovibrio vulgaris Hildenborough CbiK reveals a novel tetrameric arrangement of its subunits that are stabilized by the presence of a heme b cofactor. Whereas retaining colbaltochelatase activity, this protein has acquired a central cavity with the potential to chaperone or transport metals across the periplasmic space, thereby evolving a new use for an ancient protein subunit.

Evolution in a family of chelatases facilitated by the introduction of active site asymmetry and protein oligomerization.,Romao CV, Ladakis D, Lobo SA, Carrondo MA, Brindley AA, Deery E, Matias PM, Pickersgill RW, Saraiva LM, Warren MJ Proc Natl Acad Sci U S A. 2010 Dec 20. PMID:21173279<ref>PMID:21173279</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2xvz" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Desulfovibrio vulgaris str. Hildenborough]]
[[Category: Large Structures]]
[[Category: Carrondo MA]]
[[Category: Lobo SAL]]
[[Category: Matias PM]]
[[Category: Romao CV]]
[[Category: Saraiva LM]]