Proteomic characterization of pistachio nut allergen proteins

• The allergen pattern differentiated between the four pistachio varieties. • 2-DE analysis resulted in the identification of 11S and 7S globulin. • Shotgun analysis revealed the occurrence of 2S albumin and heat shock protein. Pistachio nut ( Pistacia vera ) is an important tree nut cultivated widely worldwide and is commonly appreciated based on its organoleptic characteristics and nutritional healthfulness. Similar to other tree nuts, the consumption of pistachio nuts is associated with moderate or severe allergic reactions in sensitized/allergic individuals. In the present study, we investigated the proteome composition of pistachio seeds using gel-based (mono- and two-dimensional electrophoresis) and gel-free (shotgun and label free quantitative) proteomics analyses. The gel-based approach allowed the identification of proteins belonging to the cupin protein family (11S and 7S globulins) and suggested the occurrence of multiple isoforms. The shotgun proteomic analysis extended the identification to allergens 2S albumin and heat shock protein, whereas label free quantitative was employed to investigate the proteomes of four different pistachio varieties. Protein pattern characterization through sophisticated techniques, such as those developed by proteomics science, allowed the identification of distinct protein markers on different pistachio cultivars.