So we see that once the oxyloacetate binds to the active side, it creates conformational changes that induces the opening of a binding site, the creation of a binding site that can bind the CETO coenzyme A. And what it also does is it basically shifts the catalytic residues in the actuide in their proper orientation, which can basically begin this aldol condensation step. So once again, the enzyme first binds the oxalo acetate into the active side, which causes the conformational changes in the structure. As shown here, we essentially go from an open confirmation to a closed confirmation. But it's not entirely closed because we still have to be able to fit the Cetal coenzyme A so that they actually can interact with one another to form the citral coenzyme A. And once the citral coenzyme A is formed, as we'll see in just a moment, only then do we have a complete closure of these active sites.