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properties have been described by Feldman (1972) and whose equation is
(Feldman, 1972; Rodbard and Feldman, 1975)
BL/FL Kdct-1-(BL+SC-Bo)/KdC+['1-[BLtSC-V/Kdc)2
+ 4VKdc]1/2l/2KdL- <3-2>
This hyperbolic Scatchard plot has one asymptote with slope (-l/KdL)
parallel to the linear Scarchard plot and an x-intercept (Bq-S^.), and
another horizontal asymptote below the x-axis at BL/FL = (-K^/K^).
The actual points on the curve are completely hypothetical and have been
calculated and placed on the plot at equally spaced intervals of
(0.275 nM) in order to indicate how specific binding values map into the
modified coordinate systems to be discussed.
We now calculate the error in the derived value of resulting
from the assumption that the concentration of free inhibitor F^ is
constant in this experiment and therefore that the expression (derived
from simple Michaelis-Menten kinetics for the case of pure competitive
inhibition) sometimes called the Edsall-Wyman equation (Cantor and
Schimmel, 1980) is valid when applied to some estimate of the "slope" of
this (actually curved) plot. The Edsall-Wyman equation can be
rearranged to the convenient "Scatchard" form given by
(cf. equation 3-1)
Bl/Fl - (BL-B0)/KdL(l+Fc/Kdc).
(3-3)