Abstract
Knowledge of the structural properties of allergenic proteins is a necessary prerequisite to better understand the molecular bases of their action, and also to design targeted structural/functional modifications. Peamaclein is a recently identified 7 kDa peach allergen that has been associated with severe allergic reactions in sensitive subjects. This protein represents the first component of a new allergen family, which has no 3D structure available yet. Here, we report the first experimental data on the 3D-structure of Peamaclein. Almost 75% of the backbone resonances, including two helical stretches in the N-terminal region, and four out of six cysteine pairs have been assigned by 2D-NMR using a natural protein sample. Simulated gastrointestinal digestion experiments have highlighted that Peamaclein is even more resistant to digestion than the peach major allergen Pru p 3. Only the heat-denatured protein becomes sensitive to intestinal proteases. Similar to Pru p 3, Peamaclein keeps its native 3D-structure up to 90 degrees C, but it becomes unfolded at temperatures of 100-120 degrees C. Heat denaturation affects the immunological properties of both peach allergens, which lose at least partially their IgE-binding epitopes. In conclusion, the data collected in this study provide a first set of information on the molecular properties of Peamaclein. Future studies could lead to the possible use of the denatured form of this protein as a vaccine, and of the inclusion of cooked peach in the diet of subjects allergic to Peamaclein. (C) 2014 Wiley Periodicals, Inc.
Original language | English |
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Pages (from-to) | 416-425 |
Number of pages | 10 |
Journal | Biopolymers |
Volume | 102 |
Issue number | 5 |
DOIs | |
Publication status | Published - Sept 2014 |
Funding
Contract grant sponsor: European Union (Bio-NMR, Project 261863)
Keywords
- Peamaclein
- Pru p 7
- NMR
- simulated gastrointestinal digestion
- heat stability
- allergen
- IgE binding
- LIPID TRANSFER PROTEINS
- NMR-SPECTROSCOPY
- FOOD
- EPITOPES
- PRU-P-3
- IDENTIFICATION
- REACTIVITY
- DIGESTION
- FEATURES
- FAMILY