Protein Engineering Aspartic Proteinases

Aspartic proteinases (1) are presently used in commercial milk, soya and cocoa processing, but there may be other applications in the longer term for designed biocatalysts for the food industry if the thermal stability, pH dependence, size and specificity can be engineered. With this objective in mind we have carried out protein engineering programmes to understand the roles of both individual amino acids and those of loops in aspartic proteinases. We have used chymosin as our model system.