Information in the EF-Hand Calcium-Binding Proteins Database from Reference 263

Information in the EF-Hand Calcium-Binding Proteins Database from Reference 263

Protein	Species	Information	Comment	Submitted By	Validated By
calbindin D9k	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 1.6E08 K₂ = 4E08 Temperature: 25 pH: 7.5 Salt concentration: no salt added Buffer: 0.002 M Tris-HCl	The calcium affinity was determined using the competitive chelator method. The chelator used was Quin2. An earlier report from the same lab gives slightly different calcium binding constants. This is because the earlier report used partially deamidated protein. The reference for the earlier report is: Linse, S., T. Drakenberg, E. Thulin, P. Sellers, K. Elmden, T. Grundstrom, S. Forsen. Structure-function relationships in EF-Hand Ca2+-binding proteins. Protein engineering and biophysical studies of calbindin D9k (1987) Biochemistry. 26, 6723-6735.	Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 5E06 K₂ = 1.6E07 Temperature: 25 pH: 7.5 Salt concentration: 50 mM KCl Buffer: 0.002 M Tris-HCl	The calcium affinity was determined using the competitive chelator method. The chelator used was Quin2. Protein concentrations were between 20 and 30 micromolar (the exact concentration is determined as part of the fitting of the titration curve.)	Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 3.2E06 K₂ = 6.3E06 Temperature: 25 pH: 7.5 Salt concentration: 100 mM KCl Buffer: 0.002 M Tris-HCl	The calcium affinity was determined using the competitive chelator method. The chelator used was Quin2. Protein concentrations were between 20 and 30 micromolar (the exact concentration is determined as part of the fitting of the titration curve.)	Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 2E06 K₂ = 3.2E06 Temperature: 25 pH: 7.5 Salt concentration: 150 mM KCl Buffer: 0.002 M Tris-HCl	The calcium affinity was determined using the competitive chelator method. The chelator used was Quin2. Protein concentrations were between 20 and 30 micromolar (the exact concentration is determined as part of the fitting of the titration curve.)	Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k mutant: E17Q	Bos taurus (cow or bovine)	This protein binds 2 equivalents of Ca ion		Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k mutant: E17Q	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 2.5E07 K₂ = 1.26E08 Temperature: 25 pH: 7.5 Salt concentration: no salt added Buffer: 0.002 M Tris-HCl		Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k mutant: E17Q	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 3.16E06 K₂ = 1E07 Temperature: 25 pH: 7.5 Salt concentration: 50 mM KCl Buffer: 0.002 M Tris-HCl		Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k mutant: E17Q	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 2E06 K₂ = 3.16E06 Temperature: 25 pH: 7.5 Salt concentration: 100 mM KCl Buffer: 0.002 M Tris-HCl		Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu
calbindin D9k mutant: E17Q	Bos taurus (cow or bovine)	Ca binding constants measured by competitive chelator: K₁ = 1.58E06 K₂ = 2.51E06 Temperature: 25 pH: 7.5 Salt concentration: 150 mM KCl Buffer: 0.002 M Tris-HCl		Melanie R. Nelson The Scripps Research Institute, Department of Molecular Biology mnelson@scripps.edu	Melanie R. Nelson mnelson@scripps.edu