MS^EBased Multiplex Protein Analysis Quantified Important Allergenic Proteins and Detected Relevant Peptides Carrying Known Epitopes in Wheat Grain Extracts

Abstract

The amount of clinically relevant, allergy-related proteins in wheat grain is still largely unknown. The application of proteomics may create a platform not only for identification and characterization, but also for quantitation of these proteins. The aim of this study was to evaluate the data-independent quantitative mass spectrometry (MS(E)) approach in combination with 76 wheat allergenic sequences downloaded from the AllergenOnline database ( www.allergenonline.org ) as a starting point. Alcohol soluble extracts of gliadin and glutenin proteins were analyzed. This approach has resulted in identification and quantification of 15 allergenic protein isoforms that belong to amylase/trypsin inhibitors, γ-gliadins, and high or low molecular weight glutenins. Additionally, several peptides carrying four previously discovered epitopes of γ-gliadin B precursor have been detected. These data were validated against the UniProt database, which contained 11764 Triticeae protein sequences. The identified allergens are discussed in relation to Baker's asthma, food allergy, wheat dependent exercise induced anaphylaxis, atopic dermatitis, and celiac disease (i.e., gluten-sensitive enteropathy). In summary, the results showed that the MS(E) approach is suitable for quantitative analysis and allergens profiling in wheat varieties and/or other food matrices.

Multiplex detection of food allergens and gluten

“…Further, the selective fractionation for proteinaceous material makes PCR nonquantitative and of questionable utility when assessing exposure doses for products that include soy protein, gluten, casein, and whey. MS and protein sequencing is still in the research stage of development and requires expensive equipment and highly trained technicians [16][17][18].…”

Determination of Gluten Peptides Associated with Celiac Disease by Mass Spectrometry

“…For complex samples, such as gluten proteins, multiplex methods of acquisition, called dataindependent acquisition (DIA) or MS E , allow to recover sample of all the ions and minimize data loss (e.g., non-fragmented precursors) [10,63]. In MS E methods, all the ions generated at ionization source are transmitted to the collision cell, which alternates between high and low energy (c.a.…”

Using 7 cm immobilized pH gradient strips to determine levels of clinically relevant proteins in wheat grain extracts

“…Classical methods for protein isolation from wheat grain are based on iso-propanol extraction (van den Broeck et al, 2009). We successfully implemented this method and have previously determined quantities of wheat grain proteins using gel-free proteomics approach (Uvackova et al, 2013a,b). In the present study we tested the phenol-based extraction protocol (Hurkman and Tanaka, 1986), which also solubilizes membrane proteins often excluded from alcohol-based protein extractions.…”