TY - JOUR
T1 - Responsiveness of the major birch allergen Bet v 1 scaffold to the gastric environment: Impact on structure and allergenic activity
AU - Sancho, Ana I.
AU - Wangorsch, Andrea
AU - Jensen, Bettina M.
AU - Watson, Andrew
AU - Alexeev, Yuri
AU - Johnson, Phil E.
AU - Mackie, Alan R.
AU - Neubauer, Angela
AU - Reese, Gerald
AU - Ballmer-Weber, Barbara
AU - Hoffmann-Sommergruber, Karin
AU - Skov, Per S.
AU - Vieths, Stefan
AU - Mills, Elisabeth N Clare
PY - 2011/11
Y1 - 2011/11
N2 - Scope: Four Bet v 1 homologous food allergens from celeriac (rApi g 1), apple (rMal d 1), peach (rPru p 1) and hazelnut (rCor a 1), were used to probe the structural responsiveness of the Bet v 1 scaffold to gastric digestion conditions and its impact on allergenicity. Methods and results: Low pH induced conformational changes of all homologues, which was reduced at physiological ionic strength for all except rPru p 1 as observed by circular dichroism (CD)-spectroscopy. The homologues were rapidly digested by pepsin, losing their IgE binding activity, although the kinetics and patterns of digestion varied subtly between homologues, rApi g 1 being the most stable. We have demonstrated for the first time that gastric phosphatidyl-choline (PC) induced conformational changes in all homologues but only rMal d 1 penetrated the PC vesicles as detected by fluorescence polarization, slowing its digestion and retaining more of its allergenic activity. PC enhanced basophil activation of all digested allergens except rApi g 1. Conclusion: The Bet v 1 scaffold is generally susceptible to low pH and pepsinolysis and interacts with PC vesicles, properties which can explain effects of the gastric environment on their allergenicity. These data show the importance of including surfactants in model digestion systems. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
AB - Scope: Four Bet v 1 homologous food allergens from celeriac (rApi g 1), apple (rMal d 1), peach (rPru p 1) and hazelnut (rCor a 1), were used to probe the structural responsiveness of the Bet v 1 scaffold to gastric digestion conditions and its impact on allergenicity. Methods and results: Low pH induced conformational changes of all homologues, which was reduced at physiological ionic strength for all except rPru p 1 as observed by circular dichroism (CD)-spectroscopy. The homologues were rapidly digested by pepsin, losing their IgE binding activity, although the kinetics and patterns of digestion varied subtly between homologues, rApi g 1 being the most stable. We have demonstrated for the first time that gastric phosphatidyl-choline (PC) induced conformational changes in all homologues but only rMal d 1 penetrated the PC vesicles as detected by fluorescence polarization, slowing its digestion and retaining more of its allergenic activity. PC enhanced basophil activation of all digested allergens except rApi g 1. Conclusion: The Bet v 1 scaffold is generally susceptible to low pH and pepsinolysis and interacts with PC vesicles, properties which can explain effects of the gastric environment on their allergenicity. These data show the importance of including surfactants in model digestion systems. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
KW - Bet v 1 homologues
KW - Food allergy
KW - Lipid-protein interaction
KW - Pepsinolysis
KW - Phosphatidylcholine
U2 - 10.1002/mnfr.201100025
DO - 10.1002/mnfr.201100025
M3 - Article
C2 - 21770047
SN - 1613-4125
VL - 55
SP - 1690
EP - 1699
JO - Molecular Nutrition and Food Research
JF - Molecular Nutrition and Food Research
IS - 11
ER -