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1qfb
From Proteopedia
(New page: 200px<br /><applet load="1qfb" size="450" color="white" frame="true" align="right" spinBox="true" caption="1qfb" /> '''THE CYCLIC PEPTIDE CONTRYPHAN-R FROM CONUS R...) |
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| - | [[Image:1qfb.jpg|left|200px]]<br /><applet load="1qfb" size=" | + | [[Image:1qfb.jpg|left|200px]]<br /><applet load="1qfb" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1qfb" /> | caption="1qfb" /> | ||
'''THE CYCLIC PEPTIDE CONTRYPHAN-R FROM CONUS RADIATUS'''<br /> | '''THE CYCLIC PEPTIDE CONTRYPHAN-R FROM CONUS RADIATUS'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Contryphan-R is a disulfide-constrained octapeptide containing a | + | Contryphan-R is a disulfide-constrained octapeptide containing a D-tryptophan that was isolated recently from venom of the cone shell Conus radiatus. The polypeptide is present in two forms in solution due to cis-trans isomerization at hydroxyproline 3. The solution structure of the major form of this unusual polypeptide, determined from NMR data, consists of a well-defined fold containing a non-hydrogen-bonded chain reversal from Gly1 to Glu5, which includes a cis-hydroxyproline and a D-Trp, and a type I beta-turn from Glu5 to Cys8. The presence of a putative salt bridge between the Glu5 carboxyl group and the N-terminal ammonium group is investigated by using various solvation models during energy minimization and is compared with the results of a pH titration. A comparison of the structure of contryphan-R with other cyclic peptide structures highlights some of the key structural determinants of these peptides and suggests that the contryphan-R fold could be exploited as a scaffold onto which unrelated protein binding surfaces could be grafted. Comparison with small disulfide-bridged loops in larger proteins shows that contryphan-R is similar to a commonly occurring loop structure found in proteins. |
==About this Structure== | ==About this Structure== | ||
| - | 1QFB is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ] with NH2 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1QFB is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ] with <scene name='pdbligand=NH2:'>NH2</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QFB OCA]. |
==Reference== | ==Reference== | ||
Solution structure of contryphan-R, a naturally occurring disulfide-bridged octapeptide containing D-tryptophan: comparison with protein loops., Pallaghy PK, Melnikova AP, Jimenez EC, Olivera BM, Norton RS, Biochemistry. 1999 Aug 31;38(35):11553-9. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=10471307 10471307] | Solution structure of contryphan-R, a naturally occurring disulfide-bridged octapeptide containing D-tryptophan: comparison with protein loops., Pallaghy PK, Melnikova AP, Jimenez EC, Olivera BM, Norton RS, Biochemistry. 1999 Aug 31;38(35):11553-9. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=10471307 10471307] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Jimenez, E | + | [[Category: Jimenez, E C.]] |
| - | [[Category: Melnikova, A | + | [[Category: Melnikova, A P.]] |
| - | [[Category: Norton, R | + | [[Category: Norton, R S.]] |
| - | [[Category: Olivera, B | + | [[Category: Olivera, B M.]] |
| - | [[Category: Pallaghy, P | + | [[Category: Pallaghy, P K.]] |
[[Category: NH2]] | [[Category: NH2]] | ||
[[Category: conus peptide]] | [[Category: conus peptide]] | ||
| Line 25: | Line 25: | ||
[[Category: venom duct peptide]] | [[Category: venom duct peptide]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:38:58 2008'' |
Revision as of 12:39, 21 February 2008
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THE CYCLIC PEPTIDE CONTRYPHAN-R FROM CONUS RADIATUS
Overview
Contryphan-R is a disulfide-constrained octapeptide containing a D-tryptophan that was isolated recently from venom of the cone shell Conus radiatus. The polypeptide is present in two forms in solution due to cis-trans isomerization at hydroxyproline 3. The solution structure of the major form of this unusual polypeptide, determined from NMR data, consists of a well-defined fold containing a non-hydrogen-bonded chain reversal from Gly1 to Glu5, which includes a cis-hydroxyproline and a D-Trp, and a type I beta-turn from Glu5 to Cys8. The presence of a putative salt bridge between the Glu5 carboxyl group and the N-terminal ammonium group is investigated by using various solvation models during energy minimization and is compared with the results of a pH titration. A comparison of the structure of contryphan-R with other cyclic peptide structures highlights some of the key structural determinants of these peptides and suggests that the contryphan-R fold could be exploited as a scaffold onto which unrelated protein binding surfaces could be grafted. Comparison with small disulfide-bridged loops in larger proteins shows that contryphan-R is similar to a commonly occurring loop structure found in proteins.
About this Structure
1QFB is a Single protein structure of sequence from [1] with as ligand. Full crystallographic information is available from OCA.
Reference
Solution structure of contryphan-R, a naturally occurring disulfide-bridged octapeptide containing D-tryptophan: comparison with protein loops., Pallaghy PK, Melnikova AP, Jimenez EC, Olivera BM, Norton RS, Biochemistry. 1999 Aug 31;38(35):11553-9. PMID:10471307
Page seeded by OCA on Thu Feb 21 14:38:58 2008
