Background: We have undertaken study on our porcine-derived trypsin generated
proteomic data of the major peanut allergen Ara h 1 from the raw and roasted peanut, to
assess possible facilitating/hindrance effects on trypsin digestion efficacy caused by post-
translational and chemical modifications (PTMs) positioned on K/R residues. If potential
hindrance effects caused by PTMs are observed with porcine trypsin, then they can be just
augmented and more pronounced within human intestinal digestion. The logic for such
reasoning is in inferior performance of human trypsin compared to porcine-derived used in
proteomic digestion protocols, also the lower trypsin-to-sample ratio and much shorter
digestion times, even though gastric digestion precedes and trypsin is not the sole digestive
enzyme.
Methods: Novel method was developed to decipher outcomes at scissile bonds using PEAKS
Studio-X+ in reassessment of high-resolution tandem mass spectrometry data on 18h-long
trypsin digestion protocol.
Results: In eight modified K/R residues involving methylation, dihydroxy and formylation,
differences in extent of miscleavage between modified and unmodified peptides, were
significantly higher (>10%) in modified peptides.
Conclusion: It is important to elucidate impact of modifications on trypsin digestion
performance, but also on other proteases involved in digestion process due to possible
effects on allergenicity of food proteins/peptides.Related to Book of Abstracts: [https://www.cost-infogest.eu/content/download/4051/35805/file/V-ICFD%20Book%20of%20Abstracts.pdf]Related to record of lecture: [https://www.youtube.com/watch?v=Dj0_1fyY724
