Supramolecular evaluation of 33-mer Gliadin peptide reveals folding and Self-assembly in vitro

HERRERA M.G.; FERNANDO ZAMARRENO; ALMUNDARAIN, MARIA JULIA; MARCELO COSTABEL; HUTTEN ANDREAS; NORBERT SEWALD; DODERO V. I

Congreso; XLI Reunión Anual de la Sociedad Argentina de Biofísica; 2012

Gliadin, a protein present in wheat, rye and barley, is not fully degraded by human beings. A 33- aminoacid peptide LQLQPF(PQPQLPY)3PQPQPF and probably other immunogenic peptides remain after the action of gastric, duodenal and pancreatic enzymes (1, 2). The 33-mer fragment is one of the proline-rich peptides which elicit an immune response in susceptible individuals and it is associated with gluten sensitivity (3) and celiac disease (4). It has been hypothesized that increased intestinal permeability is an early event in celiac disease pathogenesis (5) but it is completely unknown what endows gliadin and especially the 33-mer fragment such special features to act as stress triggers to the epithelium. Circular Dichroism and Electron Microscopy evaluation reveals formation of quaternary structures and folding depending on concentration and ionic strength. A plausible self-assembly process is presented.