Well, for the same exact reason that we have this residue to basically transform the water into a better nuclear file here, we also have a metal atom to actually bind the water and transform it into a better nuclear file so that the water can basically hydrolyze that peptide bond. So if we examine the active side, as shown here, let's say we have the zinc metal atom that is actually bound to the active side of that enzyme. And so what it does is it interacts with the oxygen as a result of this being partially negative and this having a positive charge. So they form this bond at the same time, some type of nearby residue acts as a base and usually the residue is glutamate. So this acts as a base and basically grabs off the h. It pulls the h away from this oxygen and that transforms the oxygen into a much better nuclear file. So it creates that hydroxide.