1cdp
RESTRAINED LEAST SQUARES REFINEMENT OF NATIVE (CALCIUM) AND CADMIUM-SUBSTITUTED CARP PARVALBUMIN USING X-RAY CRYSTALLOGRAPHIC DATA AT 1.6-ANGSTROMS RESOLUTIONRESTRAINED LEAST SQUARES REFINEMENT OF NATIVE (CALCIUM) AND CADMIUM-SUBSTITUTED CARP PARVALBUMIN USING X-RAY CRYSTALLOGRAPHIC DATA AT 1.6-ANGSTROMS RESOLUTION
Structural highlights
FunctionPRVB_CYPCA In muscle, parvalbumin is thought to be involved in relaxation after contraction. It binds two calcium ions. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedCarp parvalbumin coordinates calcium through one carbonyl oxygen atom and the oxygen-containing side chains of 5 amino acid residues, or 4 residues and a water molecule, in a helix-loop-helix structural motif. Other calcium-binding proteins, including calmodulin and troponin C, also possess this unique calcium-binding design, which is designated EF-hand or calmodulin fold. Parvalbumin has two such sites, labeled CD and EF. Each of the calcium-binding sites of refined structures of proteins belonging to this group has a 7-oxygen coordination sphere except those of the structure of parvalbumin as it was reported in 1975. This structure had been refined at 1.9 A using difference Fourier techniques on film data. The CD site appeared to be 6-coordinate and the EF site 8-coordinate. Results of NMR experiments using 113Cd-substituted parvalbumin, however, indicate that the sites are similar to one another with coordination number greater than 6. To resolve the inconsistency between crystallographic and NMR results, 1.6 A area detector data was collected for native and cadmium-substituted parvalbumin; the structures have been refined to R factors of 18.7% and 16.4%, respectively, with acceptable geometry and low errors in atomic coordinates. Differences between the parvalbumin structure described in 1975 and the present structure are addressed, including the discovery of 7-coordination for both the CD and EF sites. Restrained least squares refinement of native (calcium) and cadmium-substituted carp parvalbumin using X-ray crystallographic data at 1.6-A resolution.,Swain AL, Kretsinger RH, Amma EL J Biol Chem. 1989 Oct 5;264(28):16620-8. PMID:2777802[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
|