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fraction which when subtracted by one gives a negative value. The slope
and ordinate intercept will, however, have the same definition as before.
Further, K]^j/K]rrjcT and Kj are determined in the same way as for Case T
plots. The only difference here is that the values which are obtained
directly from the graph are negative. This is analogous to Lineweaver-
Burk plots in which the intercept on the 1/[s] axis is negative. Proper
substitution of these values will give rational results.
The results for u-chymotrypsin elution in the presence of CBZ--
alanylalanine are shown in Figure 25 plotted as the reciprocal of the
difference between Ve, observed elution volume, and V0, versus the re
ciprocal of CBZ-alanylalanine. The results are consistent with those
predicted in Figure 24. Note that the ordinate intercept and the slope
are both negative values.
From an intercept value of -.072 which is equal to an ordinate in
tercept of 1/Vjprjj( where Vj-rpj is equal to 31 ml, the
value of Kj^j/K£^pj is 0.55. This value is less than 1.0 which explicitly
demonstrates Case III noncompetitive elution. By substitution of the
previously determined value for equal to 8.57 mM, we find that k£^
is 15.6 mM. Finally, the soluble dissociation constant for CBZ-alanyla
lanine can be obtained by dividing the slope by the ordinate intercept.
This gives 2.5 mM which compares well with the value obtained from in
hibition kinetics of 2.3 mM.
A model has been presented which satisfies all of the observations
obtained in this work. The data have been shown to fit closely the be
havior predicted by this model and constants for the soluble binary com
plexes were obtained which are in agreement with results from an independent