Prediction of Reaction Sequences in Trisubstrate Mechanisms

When there are three substrates for an enzymatic reaction, the number of possible initial velocity patterns is large, and interpretation of the patterns is not as straightforward as when only two substrates are involved. 

We shall start the analysis of trisubstrate mechanisms by examining the form of the rate equation, proceed with the mechanistic interpretation of the absence of various terms from the general rate equation, and conclude with experimental methods for establishing the presence or absence of such terms. 

The general form of the rate equation for aU tiisubstrate mechanisms, in the absence of products and assuming linear reciprocal plots, is 

It is useful to note the identity of terms in both equations, because both equations wiU be used for the graphical analysis of initial rate data in Section 12.1.3. 

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