From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:1jlp.gif|left|200px]] | + | {{Seed}} |
| | + | [[Image:1jlp.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_1jlp| PDB=1jlp | SCENE= }} | | {{STRUCTURE_1jlp| PDB=1jlp | SCENE= }} |
| | | | |
| - | '''Solution Structure of the Noncompetitive Skeletal Muscle Nicotinic Acetylcholine Receptor Antagonist Psi-conotoxin PIIIF'''
| + | ===Solution Structure of the Noncompetitive Skeletal Muscle Nicotinic Acetylcholine Receptor Antagonist Psi-conotoxin PIIIF=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | A novel inhibitor of nicotinic acetylcholine receptors (nAChRs), psi-conotoxin Piiif, was isolated from the venom of Conus purpurascens and found to have the sequence GOOCCLYGSCROFOGCYNALCCRK-NH2. The sequence is highly homologous to that of psi-conotoxin Piiie, a previously identified noncompetitive inhibitor of Torpedo electroplax nAChR, also isolated from C. purpurascens. Both psi-conotoxins block Torpedo and mouse nicotinic acetylcholine receptors (nAChRs), but psi-Piiif is less potent by a factor of 10(1)-10(2). A high-resolution structure of psi-Piiif was determined by NMR and molecular modeling calculations. Psi-Piiif analogues containing [(13)C]-labeled cysteine at selected positions were synthesized to resolve spectral overlap of Cys side chain proton signals. The structures are well-converged, with backbone atom position RMSDs of 0.21 A for the main body of the peptide between residues 4 and 22 and 0.47 A for all residues. The overall backbone conformation is closely similar to psi-Piiie, the main difference being in the degree of conformational disorder at the two termini. Psi-Piiie and psi-Piiif have similar locations of positive charge density, although psi-Piiif has a lower overall charge. One disulfide bridge of psi-Piiif appears to undergo dynamic conformational fluctuations based on both the model and on experimental observation. Chimeras in which the three intercysteine loops were swapped between psi-Piiie and psi-Piiif were tested for inhibitory activity against Torpedo nAChRs. The third loop, which contains no charged residues in either peptide, is the prime determinant of potency in these psi-conotoxins.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_12767216}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 12767216 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_12767216}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| - | 1JLP is a [[Single protein]] structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JLP OCA]. | + | 1JLP is a [[Single protein]] structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JLP OCA]. |
| | | | |
| | ==Reference== | | ==Reference== |
| Line 25: |
Line 29: |
| | [[Category: Amidated c-terminus]] | | [[Category: Amidated c-terminus]] |
| | [[Category: Multiple disulfide bond]] | | [[Category: Multiple disulfide bond]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 21:22:44 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 1 20:26:31 2008'' |
Revision as of 17:26, 1 July 2008
Template:STRUCTURE 1jlp
Solution Structure of the Noncompetitive Skeletal Muscle Nicotinic Acetylcholine Receptor Antagonist Psi-conotoxin PIIIF
Template:ABSTRACT PUBMED 12767216
About this Structure
1JLP is a Single protein structure. Full experimental information is available from OCA.
Reference
Characterization and three-dimensional structure determination of psi-conotoxin Piiif, a novel noncompetitive antagonist of nicotinic acetylcholine receptors., Van Wagoner RM, Jacobsen RB, Olivera BM, Ireland CM, Biochemistry. 2003 Jun 3;42(21):6353-62. PMID:12767216
Page seeded by OCA on Tue Jul 1 20:26:31 2008
