Site binding kinetic model

The above results permit to present a model for the kinetics of counter-ion site binding. This model rests primarily (1) on the similarity which has been found for the frequency dependence of the absorptions due to site binding and to ion-pair formation and (2) on Manning s theory [16] for counter-ion condensation in polyelectrolyte solutions. In this model, site binding between a counter-ion C and a part P of the polyion writes ... 

At first glance the process described in Equation (6) is bimolecular in [La3 + 33], but the kinetics strictly adhere to a first-order process for the loss of starting material. However, the subsequent observation that the products of the reaction actually catalyze the decomposition of starting material allow us to treat the kinetics at each pH according to a simple one-site binding model kobs = /S x [La3 + 33] init (Kd + [La3 + 33]... 

Shou M, Mei Q, Ettore MW, et al. Sigmoidal kinetic model for two co-operative substrate-binding sites in a cytochrome P450 3A4 active site an example of the metabolism of diazepam and its derivatives. Biochem J 1999 340 845-853. 

Somewhat more critical are interpretations in which the inner layer is modelled according to some site-binding model. Figure 3.63 gives an example, which is typical in that the o°(pH) curves are well recovered but the electro-kinetic potentials are not. The former feature follows simply from the fact that the shapes of the curves are relatively simple and that at least seven parameters can be adjusted C, C. pK. pK. and (sec. 3.6e.g). In the... 

Fig. 1 Sensograms monitored from sensor surface with immobilized active chymase (left) and zymogen (right) in contact with solutions at different concentrations of the positive control (structure shown in the inset). This set-up is highly valuable to differentiate between binders that bind to active site (same pattern as for positive control) or to a different site (no response monitored from the surface with the immobilized zymogen). For the active protein the experimental response curves are overlaid with the theoretical curves obtained by fitting the experimental curves with the mathematical equations for a 1/1 kinetic model. Kinetic (kon and kott) as well as equilibrium binding parameters of the positive control given in the inset are extracted using this model...

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