BACKGROUND: Arginine kinase (AK) is expressed in a wide variety of species, including human food sources (seafood) and pests (cockroaches and moths), and has been reported as a novel allergen. However, there has been little research on the allergenicity of AK in crustaceans. In this study the physicochemical properties of AK from mud crab (Scylla paramamosain) were investigated. RESULTS: Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis, immunoblotting and inhibition enzyme-linked immunosorbent assay revealed that purified AK was unstable in thermal processing and in acid buffer. Under simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) conditions, purified AK was much more readily degraded by pepsin than by trypsin or chymotrypsin. The unpurified AK in crab myogen degraded more markedly than purified AK. In addition, in two-phase gastrointestinal digestion, AK was rapidly degraded by pepsin but resistant to trypsin and chymotrypsin digestion, while tropomyosin derived from mud crab was resistant to pepsin digestion but digested readily by trypsin or chymotrypsin. Further study of serum samples obtained from crab-allergic human patients indicated that the allergenicity of AK was markedly reduced by digestion with SGF but not SIF. CONCLUSION: AK is an important food allergen despite its unstable physicochemical properties of digestibility.
BACKGROUND: Arginine kinase (AK) is expressed in a wide variety of species, including human food sources (seafood) and pests (cockroaches and moths), and has been reported as a novel allergen. However, there has been little research on the allergenicity of AK in crustaceans. In this study the physicochemical properties of AK from mud crab (Scylla paramamosain) were investigated. RESULTS: Analysis by sodium dodecyl sulfatepolyacrylamide gel electrophoresis, immunoblotting and inhibition enzyme-linked immunosorbent assay revealed that purified AK was unstable in thermal processing and in acid buffer. Under simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) conditions, purified AK was much more readily degraded by pepsin than by trypsin or chymotrypsin. The unpurified AK in crab myogen degraded more markedly than purified AK. In addition, in two-phase gastrointestinal digestion, AK was rapidly degraded by pepsin but resistant to trypsin and chymotrypsin digestion, while tropomyosin derived from mud crab was resistant to pepsin digestion but digested readily by trypsin or chymotrypsin. Further study of serum samples obtained from crab-allergic humanpatients indicated that the allergenicity of AK was markedly reduced by digestion with SGF but not SIF. CONCLUSION: AK is an important food allergen despite its unstable physicochemical properties of digestibility.
Authors: Joana Costa; Caterina Villa; Kitty Verhoeckx; Tanja Cirkovic-Velickovic; Denise Schrama; Paola Roncada; Pedro M Rodrigues; Cristian Piras; Laura Martín-Pedraza; Linda Monaci; Elena Molina; Gabriel Mazzucchelli; Isabel Mafra; Roberta Lupi; Daniel Lozano-Ojalvo; Colette Larré; Julia Klueber; Eva Gelencser; Cristina Bueno-Diaz; Araceli Diaz-Perales; Sara Benedé; Simona Lucia Bavaro; Annette Kuehn; Karin Hoffmann-Sommergruber; Thomas Holzhauser Journal: Clin Rev Allergy Immunol Date: 2021-01-07 Impact factor: 8.667