Except now, instead of having a bond between this residue and the carbon, we have a bond between the oxygen of the water and this carbon. So inside the active side of these proteins is a pair of aspartic acid residues. They work together to transform water into a good nuclear file so that it can hydrolyze that peptide bond. So what happens is the deprotonated aspartic acid, the aspartate shown here, uses its negative charge to transform the water into a better nuclear file. So we essentially create a hydroxide and then the protonated version of the residue, the spartic acid, uses the partially positive hydrogen to basically interact with that partially negative oxygen of the carbonyl. And that creates a good electrophile.