The mutations N3P, I5P, N238P, and T 265P were introduced into VPR based on the location of the prolines found at corresponding sites in surface loops of aqualysin I (AQUI), a thermophilic structural homologue from Thermus aquaticus.
Stökkbreytingarnar N3P, I5P, N238P og T 265P sem voru framkvæmdar á VPR voru valdar samkvæmt prólínum sem eru til staðar í samstofna hitastöðuga próteasanum aqualysin I (AQUI) úr Thermus aquaticus.