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1cos
From Proteopedia
CRYSTAL STRUCTURE OF A SYNTHETIC TRIPLE-STRANDED ALPHA-HELICAL BUNDLE
Overview
The x-ray crystal structure of a peptide designed to form a double-stranded parallel coiled coil shows that it is actually a triple-stranded coiled coil formed by three alpha-helices. Unlike the designed parallel coiled coil, the helices run up-up-down. The structure is stabilized by a distinctive hydrophobic interface consisting of eight layers. As in the design, each alpha-helix in the coiled coil contributes one leucine side chain to each layer. The structure suggests that hydrophobic interactions are a dominant factor in the stabilization of coiled coils. The stoichiometry and geometry of coiled coils are primarily determined by side chain packing in the solvent-inaccessible interior, but electrostatic interactions also contribute.
About this Structure
The following page contains interesting information on the relation of 1COS with [Designer Proteins]. Full crystallographic information is available from OCA.
Reference
Crystal structure of a synthetic triple-stranded alpha-helical bundle., Lovejoy B, Choe S, Cascio D, McRorie DK, DeGrado WF, Eisenberg D, Science. 1993 Feb 26;259(5099):1288-93. PMID:8446897 Page seeded by OCA on Fri May 2 12:57:20 2008
