Kinetic Aspects of the Interaction of Blood Clotting Enzymes

Summary

Application of the methods of enzyme-kinetic analysis to the results of clotting tests is feasible and can yield useful results. However, the standard methods of enzyme kinetics are not applicable without modifications imposed by the peculiarities of the blood-clotting enzyme system. The influence of the following complicating circumstances is calculated :

1. Substrate is not present in excess.

2. Only relative measures exist for concentrations of substrate or enzymes.

3. Enzymes and substrates are often added together.

4. Reagents are not pure.

5. Clotting-time is our only measure for clotting-velocity.

Formulas are deduced, which makes it possible to recognize the effect of these complications.

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