1cll
CALMODULIN STRUCTURE REFINED AT 1.7 ANGSTROMS RESOLUTIONCALMODULIN STRUCTURE REFINED AT 1.7 ANGSTROMS RESOLUTION
Structural highlights
Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedWe have determined and refined the crystal structure of a recombinant calmodulin at 1.7 A resolution. The structure was determined by molecular replacement, using the 2.2 A published native bovine brain structure as the starting model. The final crystallographic R-factor, using 14,469 reflections in the 10.0 to 1.7 A range with structure factors exceeding 0.5 sigma, is 0.216. Bond lengths and bond angle distances have root-mean-square deviations from ideal values of 0.009 A and 0.032 A, respectively. The final model consists of 1279 non-hydrogen atoms, including four calcium ions, 1130 protein atoms, including three Asp118 side-chain atoms in double conformation, 139 water molecules and one ethanol molecule. The electron densities for residues 1 to 4 and 148 of calmodulin are poorly defined, and not included in our model, except for main-chain atoms of residue 4. The calmodulin structure from our crystals is very similar to the earlier 2.2 A structure described by Babu and coworkers with a root-mean-square deviation of 0.36 A. Calmodulin remains a dumb-bell-shaped molecule, with similar lobes and connected by a central alpha-helix. Each lobe contains three alpha-helices and two Ca2+ binding EF hand loops, with a short antiparallel beta-sheet between adjacent EF hand loops and one non-EF hand loop. There are some differences in the structure of the central helix. The crystal packing is extensively studied, and facile crystal growth along the z-axis of the triclinic crystals is explained. Herein, we describe hydrogen bonding in the various secondary structure elements and hydration of calmodulin. Calmodulin structure refined at 1.7 A resolution.,Chattopadhyaya R, Meador WE, Means AR, Quiocho FA J Mol Biol. 1992 Dec 20;228(4):1177-92. PMID:1474585[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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