HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mazzeo, M. F. Articles by Siciliano, R. A. Search for Related Content PubMed PubMed Citation Articles by Mazzeo, M. F. Articles by Siciliano, R. A. Social Bookmarking                   What's this?

Identification of transglutaminase-mediated deamidation sites in a recombinant -gliadin by advanced mass-spectrometric methodologies

¹ Centro di Spettrometria di Massa Proteomica e Biomolecolare and
² Laboratorio di Immunobiologia, Istituto di Scienze dell’Alimentazione del CNR, Avellino, Italy

Reprint requests to: Rosa Anna Siciliano, Centro di Spettrometria di Massa Proteomica e Biomolecolare, Istituto di Scienze dell’Alimentazione del CNR, via Roma 52, 83100 Avellino, Italy; e-mail: rsiciliano{at}isa.cnr.it; fax: 39-0825-781585.

Celiac disease is a permanent immune-mediated food intolerance triggered by ingestion of wheat gliadins in genetically susceptible individuals. It has been reported that tissue transglutaminase plays an important role in the onset of celiac disease by converting specific glutamine residues within gliadin fragments into glutamic acid residues. This process increases binding affinity of gliadin peptides to HLA-DQ2/DQ8 molecules, thus enhancing the immune response. The aim of the present study was to achieve a detailed structural characterization of modifications induced by transglutaminase on gliadin peptides. Therefore, structural analyses were carried out on a recombinant -gliadin and on a panel of 26 synthetic peptides, overlapping the complete protein sequence. Modified glutamine residues were identified by means of advanced mass-spectrometric methodologies on the basis of MALDI-TOF-MS and tandem mass spectrometry. Results led to the identification of 19 of 94 glutamine residues present in the recombinant -gliadin, which were converted into glutamic acid residues by a transglutaminase-mediated reaction. This allowed us to achieve a global view of the modifications induced by the enzyme on this protein. Furthermore, results gathered could likely be utilized as relevant information for a better understanding of processes leading to T-cell recognition of gliadin peptides involved in celiac disease.

Keywords: Gliadin; transglutaminase; mass spectrometry; celiac disease; posttranslational modifications

Abbreviations: CD, celiac disease • CID, collision induced dissociation • MALDI-TOF-MS, matrix-assisted laser desorption ionization–time of flight–mass spectrometry • MS/MS, tandem mass spectrometry • nanoESI-MS/MS, tandem mass spectrometric experiments performed on a hybrid quadrupole time-of-flight instrument equipped with nano-electrospray source • RP-HPLC, reverse phase high performance liquid chromatography • tTGase, tissue transglutaminase

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				S. Senger, F. Maurano, M. F. Mazzeo, M. Gaita, O. Fierro, C. S. David, R. Troncone, S. Auricchio, R. A. Siciliano, and M. Rossi Identification of Immunodominant Epitopes of {alpha}-Gliadin in HLA-DQ8 Transgenic Mice following Oral Immunization J. Immunol., December 15, 2005; 175(12): 8087 - 8095. [Abstract] [Full Text] [PDF]