But if the H atom is added from the bottom side, we're going to form that Lproline. So from the discussion above, if we can somehow build a molecule that is a transition state analog that resembles the structure of this particular molecule, then that means that transition state analog will be a very potent inhibitor of this enzyme. The proline resumes because that transition analog, that transition state analog will be able to accommodate quite easily into the active side of that enzyme. So once again the transition state of this reaction, that's the isomerization of Lproline to deprolene contains an alpha carbon that has planar or trigonal planar, that is trigonal planar. And it turns out that if we use a molecule known as parole two carboxylic acid which basically also contains trigonal planarity on that carbon as seen in the following diagram, then this will be a very, very potent inhibitor and this is in fact a transition state analog for this enzyme. So let's take a look at parole two carboxylic acid and compare the structure to the transition state of this particular reaction.