A peptidomics approach was developed to identify transglutaminase- susceptible Q residues within a pepsin-trypsin gliadin digest. Based on tagging with a monodansylcadaverine fluorescent probe, six ?/?-, ?-gliadin, and low molecular weight glutenin peptides were identified by nanospray tandem mass spectrometry. In functioning as an acyl acceptor, tissue transglutaminase was able to form complexes with the glutamine-rich gliadin peptides, whereas by lowering pH, the peptides were deamidated by transglutaminase at the same Q residues, which were previously transamidated. The main common feature shared by the peptides was the consensus sequence Q-X-P. Our findings offer relevant information for the understanding of how dietary peptides interact with the host organism in celiac disease. © 2004 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Susceptibility to transglutaminase of gliadin peptides predicted by a mass spectrometry-based assay
Gianfranco Mamone;
2004
Abstract
A peptidomics approach was developed to identify transglutaminase- susceptible Q residues within a pepsin-trypsin gliadin digest. Based on tagging with a monodansylcadaverine fluorescent probe, six ?/?-, ?-gliadin, and low molecular weight glutenin peptides were identified by nanospray tandem mass spectrometry. In functioning as an acyl acceptor, tissue transglutaminase was able to form complexes with the glutamine-rich gliadin peptides, whereas by lowering pH, the peptides were deamidated by transglutaminase at the same Q residues, which were previously transamidated. The main common feature shared by the peptides was the consensus sequence Q-X-P. Our findings offer relevant information for the understanding of how dietary peptides interact with the host organism in celiac disease. © 2004 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.