Graphic method for determination of allosteric constants |
| |
Authors: | Hiroshi Watari Yoshinori Isogai Hiroyasu Nlshikawa |
| |
Institution: | Department of Molecular Physiology, National Institute for Physiological Sciences, Okazaki 444, Japan;Department of Physiology, Kyoto Prefectural University of Medicine, Kyoto 602, Japan |
| |
Abstract: | The maximum slope of the plot, appearing in the paper of Watari & Isogai (1976), was derived algebraically as a function of allosteric constants c and αmor βm (= cαm), and the relation between L, c, and αmor βm, was also obtained, where are concentrations of unligated R and T states respectively, KRand KT are microscopic dissociation constants, and Fm is the ligand concentration at the maximum slope of the plot. When the maximum slope is increased by one, the value becomes Hill constant, n. Nomographs which enable easier estimation of allosteric constants, L and c, were constructed from the two given values, the maximum slope of the plot, n ? 1, and αmor βm, in the cases where the maximum number of ligands, N, was 2 and 4. In the nomograph, log c is plotted against log L2cN keeping the value of the maximum slope of the plot and that of αmor βm constant. These nomographs show that the representation is symmetrical in the cases of L2cN > 1 and L2cN < 1. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|