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2atg
From Proteopedia
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'''NMR structure of Retrocyclin-2 in SDS''' | '''NMR structure of Retrocyclin-2 in SDS''' | ||
| + | |||
| + | ==Overview== | ||
| + | Retrocyclins are circular mini-defensins with significant potential as agents against human immunodeficiency virus, influenza A, and herpes simplex virus. Retrocyclins bind carbohydrate-containing surface molecules such as gp120 and CD4 with high affinity (Kd, 10-100 nM), promoting their localization on cell membranes. The structural features important for activity have yet to be fully elucidated, but here, we have determined the first three-dimensional structure of a retrocyclin, namely, one of the most potent forms, retrocyclin-2. In the presence of SDS micelles, a well-defined beta-hairpin braced by three disulfide bonds that defines the cystine ladder motif is present. By contrast, a well-defined structure could not be determined in aqueous solution, suggesting that the presence of SDS micelles stabilizes the extended conformation of retrocyclin-2. Translational diffusion measurements indicate that retrocyclin-2 interacts with the SDS micelles, and such a membrane-like interaction may be an important feature in the mechanism of action of these antimicrobial peptides. Analytical ultracentrifugation and the NMR data indicated that retrocyclin-2 self-associates to form a trimer in a concentration-dependent manner. The ability to self-associate may contribute to the high-affinity binding of retrocyclins for glycoproteins by increasing the valency and enhancing the ability of retrocyclins to cross-link cell surface glycoproteins. | ||
==About this Structure== | ==About this Structure== | ||
| - | Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ATG OCA]. | + | 2ATG is a [[Single protein]] structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ATG OCA]. |
| + | |||
| + | ==Reference== | ||
| + | Retrocyclin-2: structural analysis of a potent anti-HIV theta-defensin., Daly NL, Chen YK, Rosengren KJ, Marx UC, Phillips ML, Waring AJ, Wang W, Lehrer RI, Craik DJ, Biochemistry. 2007 Sep 4;46(35):9920-8. Epub 2007 Aug 8. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17685559 17685559] | ||
| + | [[Category: Single protein]] | ||
[[Category: Chen, Y K.]] | [[Category: Chen, Y K.]] | ||
[[Category: Craik, D J.]] | [[Category: Craik, D J.]] | ||
| Line 23: | Line 30: | ||
[[Category: Wang, W.]] | [[Category: Wang, W.]] | ||
[[Category: Waring, A J.]] | [[Category: Waring, A J.]] | ||
| + | [[Category: Antiviral protein]] | ||
[[Category: Beta-sheet]] | [[Category: Beta-sheet]] | ||
[[Category: Circular peptide]] | [[Category: Circular peptide]] | ||
[[Category: Laddered disulfide connectivity]] | [[Category: Laddered disulfide connectivity]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed May 28 09:27:46 2008'' |
Revision as of 06:27, 28 May 2008
NMR structure of Retrocyclin-2 in SDS
Overview
Retrocyclins are circular mini-defensins with significant potential as agents against human immunodeficiency virus, influenza A, and herpes simplex virus. Retrocyclins bind carbohydrate-containing surface molecules such as gp120 and CD4 with high affinity (Kd, 10-100 nM), promoting their localization on cell membranes. The structural features important for activity have yet to be fully elucidated, but here, we have determined the first three-dimensional structure of a retrocyclin, namely, one of the most potent forms, retrocyclin-2. In the presence of SDS micelles, a well-defined beta-hairpin braced by three disulfide bonds that defines the cystine ladder motif is present. By contrast, a well-defined structure could not be determined in aqueous solution, suggesting that the presence of SDS micelles stabilizes the extended conformation of retrocyclin-2. Translational diffusion measurements indicate that retrocyclin-2 interacts with the SDS micelles, and such a membrane-like interaction may be an important feature in the mechanism of action of these antimicrobial peptides. Analytical ultracentrifugation and the NMR data indicated that retrocyclin-2 self-associates to form a trimer in a concentration-dependent manner. The ability to self-associate may contribute to the high-affinity binding of retrocyclins for glycoproteins by increasing the valency and enhancing the ability of retrocyclins to cross-link cell surface glycoproteins.
About this Structure
2ATG is a Single protein structure. Full crystallographic information is available from OCA.
Reference
Retrocyclin-2: structural analysis of a potent anti-HIV theta-defensin., Daly NL, Chen YK, Rosengren KJ, Marx UC, Phillips ML, Waring AJ, Wang W, Lehrer RI, Craik DJ, Biochemistry. 2007 Sep 4;46(35):9920-8. Epub 2007 Aug 8. PMID:17685559 Page seeded by OCA on Wed May 28 09:27:46 2008
