Determination of free and bound microtubular protein and guanine nucleotide under equilibrium conditions.

@article{Zeeberg1979DeterminationOF,
  title={Determination of free and bound microtubular protein and guanine nucleotide under equilibrium conditions.},
  author={B Zeeberg and Michael Caplow},
  journal={Biochemistry},
  year={1979},
  volume={18 18},
  pages={3880-6}
}
The dissociation constant for GDP binding to the E site of tubulin isolated by chromatography on Sepharose 6B is equal to 6.1 X 10(-8) M, as determined by the Hummel-Dryer procedure. This is smaller than any previously reported value, and the discrepancy with earlir results is analyzed. By use of a recently described column centrifugation procedure [Penefsky, H. S. (1977) J. Biol. Chem. 252, 2891-2899], it was established that GDP and GTP bind to the same site. GTP is bound 2.8-fold tighter… CONTINUE READING