„Schiffe Versenken“: Optimierung einer hochaktiven Saccharose-Isomerase

The sucrose isomerase SmuA from Serratia plymuthica catalyses the production of isomaltulose, an artificial sweetener used in the food industry. To suppress the formation of the hygroscopic by-product trehalulose we applied a semirational protein engineering strategy inspired by the “battleship” board game. After seven cycles of introducing amino acid exchanges around the active site and investigating their influence on the enzymatic product profile we obtained a triple mutant that showed 2.3 times less trehalulose formation but had retained high catalytic efficiency.