title: Studies of calmodulin structure: laser raman spectroscopy of biomolecules.
abstract: The structure of bovine brain calmodulin was probed by using laser Raman spectroscopy to elucidate cation-induced conformational changes in the protein. Local changes, most likely reflecting metal binding but not rearrangement of the peptide backbone, were observed in the presence of calcium or magnesium. A conformational change involving the peptide backbone and secondary structure content of calmodulin was observed only in the presence of calcium. The calcium-induced conformational change in the peptide backbone involves increased alpha helix and beta sheet. This was the only major calcium-specific change observed in the Raman spectrum, which suggests that the flexibility of the backbone conformation may play a critical role in the physiological activity of calmodulin.
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000378:metabolism; D000818:Animals; D001921:Brain; D002135:Calcium-Binding Proteins / Q000494:pharmacology; D002147:Calmodulin / Q000494:pharmacology; D002417:Cattle; D046911:Macromolecular Substances; D011487:Protein Conformation; D013056:Spectrophotometry, Ultraviolet; D013059:Spectrum Analysis, Raman
chemical_list: D002135:Calcium-Binding Proteins; D002147:Calmodulin; D046911:Macromolecular Substances; D015105:3',5'-Cyclic-AMP Phosphodiesterases