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2k7g

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Revision as of 08:50, 10 September 2015

Solution Structure of varv F

Structural highlights

2k7g is a 1 chain structure with sequence from Viola arvensis. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[VARF_VIOAR] Probably participates in a plant defense mechanism. Has cytotoxic activity against a variety of drug-resistant and drug-sensitive human tumor cell lines.[PROSITE-ProRule:PRU00395]^[1]

Publication Abstract from PubMed

Cyclotides are a family of plant defense proteins that are highly resistant to adverse chemical, thermal, and enzymatic treatment. Here, we present the first crystal structure of a cyclotide, varv F, from the European field pansy, Viola arvensis, determined at a resolution of 1.8 A. The solution state NMR structure was also determined and, combined with measurements of biophysical parameters for several cyclotides, provided an insight into the structural features that account for the remarkable stability of the cyclotide family. The x-ray data confirm the cystine knot topology and the circular backbone, and delineate a conserved network of hydrogen bonds that contribute to the stability of the cyclotide fold. The structural role of a highly conserved Glu residue that has been shown to regulate cyclotide function was also determined, verifying its involvement in a stabilizing hydrogen bond network. We also demonstrate that varv F binds to dodecylphosphocholine micelles, defining the binding orientation and showing that its structure remains unchanged upon binding, further demonstrating that the cyclotide fold is rigid. This study provides a biological insight into the mechanism by which cyclotides maintain their native activity in the unfavorable environment of predator insect guts. It also provides a structural basis for explaining how a cluster of residues important for bioactivity may be involved in self-association interactions in membranes. As well as being important for their bioactivity, the structural rigidity of cyclotides makes them very suitable as a stable template for peptide-based drug design.

Combined X-ray and NMR analysis of the stability of the cyclotide cystine knot fold that underpins its insecticidal activity and potential use as a drug scaffold.,Wang CK, Hu SH, Martin JL, Sjogren T, Hajdu J, Bohlin L, Claeson P, Goransson U, Rosengren KJ, Tang J, Tan NH, Craik DJ J Biol Chem. 2009 Apr 17;284(16):10672-83. Epub 2009 Feb 10. PMID:19211551^[2]

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

References

↑ Lindholm P, Goransson U, Johansson S, Claeson P, Gullbo J, Larsson R, Bohlin L, Backlund A. Cyclotides: a novel type of cytotoxic agents. Mol Cancer Ther. 2002 Apr;1(6):365-9. PMID:12477048
↑ Wang CK, Hu SH, Martin JL, Sjogren T, Hajdu J, Bohlin L, Claeson P, Goransson U, Rosengren KJ, Tang J, Tan NH, Craik DJ. Combined X-ray and NMR analysis of the stability of the cyclotide cystine knot fold that underpins its insecticidal activity and potential use as a drug scaffold. J Biol Chem. 2009 Apr 17;284(16):10672-83. Epub 2009 Feb 10. PMID:19211551 doi:10.1074/jbc.M900021200

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/2k7g"

@@ Line 3: / Line 3: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[2k7g]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Viola_arvensis Viola arvensis]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2K7G OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2K7G FirstGlance]. <br>
-</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=2k7g FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2k7g OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2k7g RCSB], [http://www.ebi.ac.uk/pdbsum/2k7g PDBsum]</span></td></tr>
+</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=2k7g FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2k7g OCA], [http://pdbe.org/2k7g PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2k7g RCSB], [http://www.ebi.ac.uk/pdbsum/2k7g PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 15: / Line 15: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 2k7g" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

2k7g

From Proteopedia

Revision as of 08:50, 10 September 2015

Solution Structure of varv F

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

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