Enzymes hexakinase

A better understanding of complicated recognition processes, such as that of hexakinase enzyme in which the host cavity is created in the guest presence [2], will be achieved. 

How a preferential binding of a reactant species over a product species affects the thermodynamic activities is influenced by the nature of the reaction. For reactions that occur on the surface of the enzyme, the preferential binding of reactant species causes its activity to be increased relative to that of the product and the conversion to products on the binding surface is favored. When the reaction takes place in the bulk solution, a preferential binding of the reactant species to the surface lowers its activity relative to that of the product, and the reverse reaction becomes favored. The hexakinase-glucose-ATP reaction is an example of the first type. 

Figure T.l. Model of the hexakinase enzyme (a) the free cavity in hexakinase, (b) adsorbed glucose in the cavityP l.

Figure 7.1c. Model of the hexakinase enzyme adsorption of glucoseP l.

We will give a detailed description of recent insights obtained especially for the widely studied hexakinase enzyme, which catalyzes the phosphorylation of glucose. The phosphorylation of glucose by hexakinase has been modeled in detail by simulating the reaction events that can occur in the enzyme cleft PI. The free hexakinase enzyme molecule is... 

The optimum induced fit between the enzyme cavity and the reacting substrate enables the enzyme for a particular reaction to discriminate readily between reactants that differ in size. This is illustrated in Fig. 7.2 for the conversion of glucose and closely related molecules by the hexakinase enzyme. 

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