A new microbial gluten-degrading prolyl endopeptidase: Potential application in celiac disease to reduce gluten immunogenic peptides.

Gluten is a complex of proteins present in barley, wheat, rye and several varieties of oats that triggers celiac disease in genetically predisposed subjects. Gluten is notoriously difficult to digest by mammalian proteolytic enzymes and therefore, proline-rich digestion-resistant peptides contain multiple immunogenic epitopes. Prolyl endopeptidases (PEP) hydrolyse internal proline residues on the carboxyl side of peptides and have been proposed for food gluten detoxification and as oral enzyme supplementation for celiacs.