A comparative proteomic analysis between common cashew tree (Anacardium occidentale L.) and early dwarf faga 11 (Anacardium occidentale var. nanum) seeds reveals exclusively expressed allergenic proteins

Abstract

The cashew tree (Anacardium occidentale L.) is a plant native to Brazil and has great commercial value. Among the products marketed from cashew trees, the cashew nut is the most valued, especially for export. However, the presence of allergenic proteins poses a potential threat to those allergic to cashew nuts, but molecular tools including proteomic analysis may be used to allow identification of cashew genotypes with altered allergen content. Here we aimed to identify differentially expressed proteins in common cashew seeds and dwarf FAGA 11 through proteomic analysis. Proteins differentially expressed were excised from two-dimensional gels and analyzed by mass spectrometry (ESI-Q-TOF), then identified using the MASCOT. A total of 18 proteins were analyzed, but only 5 (27%) were not identified. Among the proteins that are unique to common cashew, stand out: the precursor of globulin 11S and Ana 2 protein, both classified as allergenic proteins. The protein Ana o 2 is an 11S globulin and is considered the second most abundant allergen in cashew nuts. Thus, allergenic proteins found in common cashew nuts were observed as expected, but the allergen content of the dwarf FAGA 11 cashew nuts was altered and could represent a new source for biological diversity and allergen content for improved breeding and biotechnological applications.