Well, when we'll discuss the process of glycolysis, we'll see that an intermediate molecule in glycolysis is known as dihydroxy acetone phosphate. And what happens in glycolysis is dihydroxy acetone phosphate is transformed into another isomer by an enzyme we call triosphosphate isomerase. Now, inside the active side of triosphosphate isomerase, we have this glutamate molecule. And this glutamate molecule, the amino acid glutamate, essentially is responsible for this catalyzation process from transforming dihydroxy acetone phosphate into another isomer. Now, if we add bromoacetal phosphate, this molecule into the mixture, notice how this is almost exactly the same in structure as this original natural substrate. The only difference is, instead of this hydroxyl group, we have this bromide.