ALERGENUL ARA H3, GLOBULINA DE REZERVĂ 11S DIN SEMINŢELE DE ARAHIDE 2. PROTEOLIZA LIMITATĂ CU TRIPSINĂ

Ala CHERDIVARĂ, Angela RUDACOVA, Serghei RUDACOV, Andrei ŞUTOV Universitatea de Stat din Moldova

Abstract

ALLERGEN ARA H3, STORAGE 11S GLOBULIN FROM PEANUT SEEDS  

2. TRYPSIN LIMITED PROTEOLYSIS 

The final product of trypsin limited proteolysis of a subunit of storage 11S globulin from peanut seeds Ara h3 (pdb|3c3v) consists of the intact -chain and -chain fragments K and N. The fragment K disulfide bonded with the -chain corresponds to the N-terminal half of the -barrel (Ile1-Arg109), and the fragment N corresponds to the adjacent C-terminal half (Lys110-Arg213). Identification of the respective -chain cleavage points is based on the results of electrophoresis, the molecular mass of the residual protein determined using two independent methods, and on the analysis of the level of accessibility of amino acid residues in a model structure of Ara h3 hexamer molecule. The destruction of the -chain C-terminal region occurs in the course of formation of the fragments K and N. This region contains three of the four antigen determinants (IgE epitopes) identified in Ara h3. Thus, it seems likely that trypsin limited proteolysis can essentially decrease the allergenicity level of the peanut 11S globulin. 

Keywords: seed 11S globulins, allergens, IgE epitopes, proteolysis, trypsin, peanut.