Abstract
Coeliac disease (CD) is a chronic autoimmune inflammatory intestinal disease with known environmental trigger - gluten and a strong genetic component. Coeliac-toxic gliadin peptides result by proteolytic digestion of gluten proteins and peptides containing the sequences Pro-Ser-Gln-Gln and Gln-Gln-Gln-Pro may be involved in the pathogenesis of coeliac disease.
We published in 1988 alpha-gliadin fragments by peptic-tryptic-protease digestion (PTP-aGli). These PTP peptides were analysed by RP-HPLC, MALDI-TOF and BLAST searching and three important sequences QPFPQPQLP, QLQPFPQPQ and RPQQPYPQPQPQ were detected.
In previous papers we demonstrate the opioid activity of PTP-aGli investigated in vitro by the contraction of guinea pig ileum. The tendency to form a beta-turn in alpha-gliadin was estimated using the B-cell determinant prediction program based on the Chou and Fasman probability of beta-turn formation.