Growing calmodulin crystals for X-ray diffraction studies at room temperature in 2 days.
Crystals of bovine brain calmodulin have been grown using a novel procedure which utilizes a mixture of alcohols as a precipitant. Crystals were grown by vapor diffusion at room temperature in the presence of 15% ethanol, 25% 2-methyl-2,4-pentanediol, 5.0 mM calcium chloride, and 10.0 mM sodium acetate buffer at pH 4.0. Crystals were visible within 4 h and grew to 0.75 X 0.3 X 0.125 mm in 2 days, without seeding. The crystals of calmodulin are isomorphous with those found by W. J. Cook, J. R. Dedman, A. R. Means, and C. E. Bugg (1980, J. Biol. Chem. 255, 8152-8153). The protein crystallizes in space group P1 with unit cell dimensions a = 29.92 A, b = 55.96 A, c = 24.75 A, alpha = 93.81 degrees, beta = 99.24 degrees, and gamma = 88.40 degrees.
D000438:Alcohols; D000818:Animals; D001923:Brain Chemistry; D002147:Calmodulin; D002417:Cattle; D003461:Crystallography; D000431:Ethanol; D014961:X-Ray Diffraction
D000438:Alcohols; D002147:Calmodulin; D000431:Ethanol