Physicochemical properties and thermal stability of Lep w 1, the major allergen of whiff

Abstract

Whiff (Lepidorhombus whiffiagonis) is a fish frequently consumed in Spain. Lep w 1, its major allergen, is a calcium-binding beta-parvalbumin. The resistance of Lep w 1 to heat denaturation and to digestion were studied by circular dichroism spectroscopy and by in vitro gastric digestion systems. Purified Lep w 1 was thermally stable up to 65 degrees C at neutral pH. Calcium depletion resulted in a change of its structure as determined by circular dichroism spectroscopy. A partial loss of structure was also observed at acidic pH; however, the allergen retained its full IgE-binding ability. The partially denatured Lep w 1 was easily digested by pepsin within 2 min. Further, the IgE reactivity of proteins extracted from cooked fish and their stability to proteolysis were analyzed. The extract revealed a higher number of IgE reactive bands than an extract from uncooked fish. IgE binding to these proteins could not be inhibited by an extract from uncooked fish. In contrast to a raw fish extract, the cooked extract showed higher resistance to pepsinolysis. The stability of Lep w 1 to thermal denaturation and digestion explains the high allergenicity of whiff.

Effects of High-Pressure Treatment on the Muscle Proteome of Hake by Bottom-Up Proteomics

“…These proteins are thermostable proteins that present high stability towards food processing and enzymatic digestion. 33 In the current study, it was also found that hake parvalbumins present a remarkable stability to HP treatments and even showed an increase in their intensity after applying pressure ≥ 430 MPa (Figure 3s). These results might be used for the development of further allergenic studies using different hake HP treatments and sera from parvalbumin allergic patients.…”

Diagnosis of fish and shellfish allergies

“… 14 Interestingly, calcium depletion reduced IgE binding to parvalbumin in most patient sera. 14 Fish parvalbumin is thermally stable 15 and maintains its allergenic activity and antigenicity even under acidic conditions and after pepsinolysis. 13 , 16 Short burst swimming in fish is powered by white muscles, which have a higher parvalbumin content than the dark muscles that drives continuous stroke.…”

Diagnosis of Allergy to Mammals and Fish: Cross-Reactive vs. Specific Markers

“…They are low molecular weight proteins (10–12 kDa) that are highly stable (e.g. upon heating, enzymatic digestion) and bind bivalent ions such as calcium or magnesium [ 98 ]. Parvalbumins belong to the ‘EF hand’-protein family as the ion-binding is affected by structural motifs, which are characteristic for this family [ 99 ].…”