Peptide hydrolysis proceeds in eight steps. The first step is substrate binding. Upon substrate binding, the alkoxide of the side chain of serine will attack the carbonyl carbon atom, creating a tetrahedral intermediate with a negative charge on oxygen. To neutralize the negative charge, a structure located in the polypeptide backbone known as the oxyanion hole will interact with the oxygen, more specifically, the –NH of an asparagine residue. After the formation of the tetrahedral intermediate, the histidine will donate a proton to the amino group formed by cleavage of the peptide bond, causing the release of the amine component of the sbstrate and the formation of the acyl-enzyme intermediate. After the acylation is complete, deacylation will occur. Water will come in and bind at the site that the amine group has just departed from. Histidine will strip a hydrogen away from the water, creating a hydroxyl group that will attack the carbonyl carbon atom, creating yet another tetrahedral intermediate with a negative charge around the oxygen. Similarly to the first time, the oxyanion hole will help neutralize this charge. The tetrahedron will eventually collapse, forming the carboxylic acid product. Release of this product resets the enzyme for acylation again.