Isotope-edited multidimensional NMR of calcineurin B in the presence of the non-deuterated detergent CHAPS.
At the concentration needed for NMR, the calcium-saturated form of calcineurin B dissolved in water shows resonance line widths that indicate aggregation of this protein. Although the line width or aggregation state can be influenced to some degree by temperature, pH, and salt concentrations, in the absence of detergent no conditions could be found where the protein behaved as a monomeric unit. In the presence of a 10- to 20-fold molar excess of the zwitterionic detergent 3-[(3-cholamidopropyl)-dimethyl-ammonio]-1-propanesulfonate (CHAPS), resonance line widths were considerably narrower and were compatible with a protein of approximately 25 kDa. The presence of the NMR signals of the non-deuterated CHAPS does not interfere with modern isotope-directed NMR studies as the signals from protons not attached to 15N or 13C are removed by isotope filtering and purge pulses.
Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
J
J
Anglister
S
S
Grzesiek
H
H
Ren
C B
CB
Klee
A
A
Bax
D019703:Calcineurin; D002148:Calmodulin-Binding Proteins / Q000737:chemistry*; D002247:Carbon Isotopes; D002793:Cholic Acids; D003902:Detergents; D007553:Isotope Labeling; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D009587:Nitrogen Isotopes; D010749:Phosphoprotein Phosphatases / Q000737:chemistry*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry
D002148:Calmodulin-Binding Proteins; D002247:Carbon Isotopes; D002793:Cholic Acids; D003902:Detergents; D009587:Nitrogen Isotopes; D011994:Recombinant Proteins; D019703:Calcineurin; D010749:Phosphoprotein Phosphatases; C028213:3-((3-cholamidopropyl)dimethylammonium)-1-propanesulfonate