title: LC/MS analysis of proteolytic peptides in wheat extracts for determining the content of the allergen amylase/trypsin inhibitor CM3: influence of growing area and variety.
abstract: Food allergy from wheat is triggered by several protein classes, such as LTPs, ω5-gliadins and α-amylase/trypsin inhibitors. The latter proteins, belonging to the prolamin superfamily, are mostly involved in baker's asthma, a form of occupational allergy in which the sensitization occurs through the respiratory tract. α-Amylase/trypsin inhibitors were also found to be involved in wheat-related atopic dermatitis. In this work, the allergen Tri a 30 (the CM3 α-amylase/trypsin inhibitor) was quantified in durum wheat salt soluble extracts using a peptidomic approach. CM3 protein identification was confirmed by using LTQ-OrbiTrap analysis on peptides obtained from the enzymatically digested protein separated by gel electrophoresis. Then, marker peptides derived from the protein after enzymatic cleavage of the full wheat extracts were identified by LC-MS/MS. One of them was used as marker for quantitative determination on an UPLC/ESI-MS system by using its isotopically labelled analogue as internal standard, allowing to assess the protein content in the different samples. The CM3 allergenic proteins were found to greatly vary among different cultivation areas.
authors.affiliation: Department of Food Science, University of Parma, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Prandi
authors.forename: Andrea
authors.initials: A
authors.lastname: Faccini
authors.forename: Tullia
authors.initials: T
authors.lastname: Tedeschi
authors.forename: Gianni
authors.initials: G
authors.lastname: Galaverna
authors.forename: Stefano
authors.initials: S
authors.lastname: Sforza
mesh_terms: D000485:Allergens / Q000737:chemistry* / Q000302:isolation & purification; D000595:Amino Acid Sequence; D000681:Amylases / Q000037:antagonists & inhibitors*; D002853:Chromatography, Liquid; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D005843:Geography; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D010455:Peptides / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry* / Q000302:isolation & purification; D014908:Triticum / Q000737:chemistry* / Q000145:classification / Q000254:growth & development; D014361:Trypsin Inhibitors / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000485:Allergens; D004791:Enzyme Inhibitors; D010455:Peptides; D010940:Plant Proteins; D014361:Trypsin Inhibitors; C071392:CM protein, Triticum aestivum; D000681:Amylases