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1jjd

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Revision as of 13:48, 11 September 2015

NMR structure of the Cyanobacterial Metallothionein SmtA

Structural highlights

1jjd is a 1 chain structure with sequence from Anacystis nidulans r2. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Gene:	smtA (Anacystis nidulans R2)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[MT_SYNE7] May play a role in essential metal ion homeostasis (especially zinc homeostasis) and resistance to certain non-essential metal ions. Metallothioneins have a high content of cysteine residues that bind various heavy metals.

Publication Abstract from PubMed

Zinc is essential for many cellular processes, including DNA synthesis, transcription, and translation, but excess can be toxic. A zinc-induced gene, smtA, is required for normal zinc-tolerance in the cyanobacterium Synechococcus PCC 7942. Here we report that the protein SmtA contains a cleft lined with Cys-sulfur and His-imidazole ligands that binds four zinc ions in a Zn(4)Cys(9)His(2) cluster. The thiolate sulfurs of five Cys ligands provide bridges between the two ZnCys(4) and two ZnCys(3)His sites, giving two fused six-membered rings with distorted boat conformations. The inorganic core strongly resembles the Zn(4)Cys(11) cluster of mammalian metallothionein, despite different amino acid sequences, a different linear order of the ligands, and presence of histidine ligands. Also, SmtA contains elements of secondary structure not found in metallothioneins. One of the two Cys(4)-coordinated zinc ions in SmtA readily exchanges with exogenous metal ((111)Cd), whereas the other is inert. The thiolate sulfur ligands bound to zinc in this site are buried within the protein. Regions of beta-strand and alpha-helix surround the inert site to form a zinc finger resembling the zinc fingers in GATA and LIM-domain proteins. Eukaryotic zinc fingers interact specifically with other proteins or DNA and an analogous interaction can therefore be anticipated for prokaryotic zinc fingers. SmtA now provides structural proof for the existence of zinc fingers in prokaryotes, and sequences related to the zinc finger motif can be identified in several bacterial genomes.

A metallothionein containing a zinc finger within a four-metal cluster protects a bacterium from zinc toxicity.,Blindauer CA, Harrison MD, Parkinson JA, Robinson AK, Cavet JS, Robinson NJ, Sadler PJ Proc Natl Acad Sci U S A. 2001 Aug 14;98(17):9593-8. Epub 2001 Aug 7. PMID:11493688^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Blindauer CA, Harrison MD, Parkinson JA, Robinson AK, Cavet JS, Robinson NJ, Sadler PJ. A metallothionein containing a zinc finger within a four-metal cluster protects a bacterium from zinc toxicity. Proc Natl Acad Sci U S A. 2001 Aug 14;98(17):9593-8. Epub 2001 Aug 7. PMID:11493688 doi:10.1073/pnas.171120098

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1jjd"

@@ Line 5: / Line 5: @@
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">smtA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1140 Anacystis nidulans R2])</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1jjd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jjd OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1jjd RCSB], [http://www.ebi.ac.uk/pdbsum/1jjd PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1jjd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jjd OCA], [http://pdbe.org/1jjd PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1jjd RCSB], [http://www.ebi.ac.uk/pdbsum/1jjd PDBsum]</span></td></tr>
 </table>
 == Function ==
-[[http://www.uniprot.org/uniprot/MT_SYNP7 MT_SYNP7]] May play a role in essential metal ion homeostasis (especially zinc homeostasis) and resistance to certain non-essential metal ions. Metallothioneins have a high content of cysteine residues that bind various heavy metals.
+[[http://www.uniprot.org/uniprot/MT_SYNE7 MT_SYNE7]] May play a role in essential metal ion homeostasis (especially zinc homeostasis) and resistance to certain non-essential metal ions. Metallothioneins have a high content of cysteine residues that bind various heavy metals.
 <div style="background-color:#fffaf0;">
 == Publication Abstract from PubMed ==
@@ Line 17: / Line 17: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 1jjd" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

1jjd

From Proteopedia

Revision as of 13:48, 11 September 2015

NMR structure of the Cyanobacterial Metallothionein SmtA

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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