3cys: Difference between revisions

[[Image:3cys.gif|left|200px]]<br /><applet load="3cys" size="350" color="white" frame="true" align="right" spinBox="true"  

The three-dimensional NMR solution structure of the cyclophilin A (Cyp)-cyclosporin A (CsA) complex was determined, and here we provide a detailed description of the analysis of the NMR data and the structure calculation. Using 15N- and 13C-resolved three- and four-dimensional [1H,1H]-nuclear Overhauser enhancement (NOE) spectroscopy with uniformly isotope-labeled Cyp in the complex, a final data set of 1810 intra-Cyp, 107 intra-CsA and 63 intermolecular NOE upper distance constraints was collected as input for the structure calculation with the program DIANA. A group of DIANA conformers, selected by a previously described analysis of the dependence of the maximal root-mean-square deviation (rmsd) among the individual conformers on the residual target function value, was subjected to energy refinement with the program FANTOM. The 22 best energy-refined conformers were then used to represent the solution structure. The average rmsd relative to the mean structure of these 22 conformers is 1.1 A for the backbone atoms of all residues of the complex. The molecular architecture of Cyp in the Cyp-CsA complex includes an eight-stranded antiparallel beta-barrel, which is closed on each side by an amphipathic helix. CsA is bound in a cavity formed by part of the barrel surface and four loops with nonregular secondary structure. Comparison of this structure with structures of Cyp-CsA and other Cyp-peptide complexes determined by different approaches shows extensive similarities.

3CYS is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/ ]. This structure supersedes the now removed PDB entry 2CYS. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3CYS OCA].  

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:08:59 2008''