We basically form our glutamate and this THF, the tetrahydropholate abstracts this, forming this molecule here. So once the histidine is transformed into glutamate, then we simply undergo this step that is catalyzed by glutamate dehydrogenase to form the alpha ketoglutrates. So that's five. Now let's look at four. So, Proline, how do we transform proline into glutamates? Well, this is the reaction process here.