1c1g
From Proteopedia
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CRYSTAL STRUCTURE OF TROPOMYOSIN AT 7 ANGSTROMS RESOLUTION IN THE SPERMINE-INDUCED CRYSTAL FORM
Overview
Tropomyosin is a 400A-long coiled coil that polymerizes to form a continuous filament that associates with actin in muscle and numerous non-muscle cells. Tropomyosin and troponin together form a calcium-sensitive switch that is responsible for thin-filament regulation of striated muscle. Subtle structural features of the molecule, including non-canonical aspects of its coiled-coil motif, undoubtedly influence its association with f-actin and its role in thin filament regulation. Previously, careful inspection of native diffraction intensities was sufficient to construct a model of tropomyosin at 9A resolution in a spermine-induced crystal form that diffracts anisotropically to 4A resolution. Single isomorphous replacement (SIR) phasing has now provided an empirical determination of the structure at 7A resolution. A novel method of heavy-atom analysis was used to overcome difficulties in interpretation of extremely anisotropic diffraction. The packing arrangement of the molecules in the crystal, and important aspects of the tropomyosin geometry such as non-uniformities of the pitch and variable bending and radius of the coiled coil are evident.
About this Structure
1C1G is a Single protein structure of sequence from Sus scrofa. Full crystallographic information is available from OCA.
Reference
Crystal structure of tropomyosin at 7 Angstroms resolution., Whitby FG, Phillips GN Jr, Proteins. 2000 Jan 1;38(1):49-59. PMID:10651038
Page seeded by OCA on Thu Feb 21 12:01:21 2008
