Using two-dimensional electrophoresis to explore the link between protein kinetic stability and tree nuts allergenicity

Abstract

The results show the presence of SDS-resistant oligomers/aggregates and proteins, a direct evidence of high kinetic stability, for some tree nuts and negligible amounts for others. Overall, the results did not show a clear link between protein kinetic stability and tree nut allergenicity, perhaps because the reduction of disulfide bonds present in many allergenic proteins compromises its kinetic stability. Further studies will be needed under reducing and nonreducing conditions and using additional methods to further explore the link between protein kinetic stability and its allergenic potential.

Tree nut allergies are a prevalent medical ailment that affects approximately 5% of the world’s population. Many have studied in detail allergenic proteins and their ability to produce mild, severe, and fatal food allergic reactions. However, a direct link between allergenicity and their proteins has not been fully established when referring to the role of conformational stability, resistance to pH, and degradation. Kinetically Stable Proteins (KSPs) inherently protect against aggregation and proteolytic degradation. Thus, in order to explore the role of kinetic stability in the allergenicity of tree nut proteins, a gel method known as diagonal two-dimensional (D2D) SDS-PAGE, which identifies SDS-resistant proteins (a proxy for kinetic stability) was used to accomplish this task. In this study, nine allergenic tree nuts were analyzed by D2D SDS-PAGE in the presence of the disulfide reducing compound dithiothreitol (DTT).