Diazosuccinic ester, N2 C(C02C2H5)2, is similarly prepared by the action of nitrous acid on the hydrochloride of aspartic ester.
Hydrolysis by means of acids or alkalis converts the asparagines into aspartic acid; whilst on heating with water in a sealed tube they are converted into ammonium aspartate.
This could be an activated water molecule as seen in aspartic proteinases or an amino acid side chain.
In aspartic peptidases, the water molecule is directly bound by the side chains of aspartic residues.
The predicted catalytic serine, histidine and aspartic acid residues are shown in ball-and-stick representation.