So once this conformational change takes place, it also creates a binding site for acetylco enzyme A and shifts the catalytic residues in the active side of the enzyme into their proper orientation and position so that the catalysis reaction can actually take place. So to summarize how this process of aldole condensation, basically the first process, step one of the citric acid cycle actually takes place, let's take a look at three of these three diagrams, beginning with diagram number one. Now, in diagram number one, we have the active side of our enzyme and there are three different types of residues that basically catalyze this process. We have histidine 274, we have histidine 320, and we also have Aspartate 375. Now, this here is basically the Cecil coenzyme A. And this here is the oxalo acetate.