Analysis of the allergenic proteins in black tiger prawn (Penaeus monodon) and characterization of the major allergen tropomyosin using mass spectrometry

Abstract

Crustaceans are the third most prevalent cause of food-induced anaphylaxis after peanuts and treenuts. The severity of the allergenic proteins depends mainly on the amino acid sequence that induces production of IgE antibodies. In black tiger prawn (Penaeus monodon), the crude protein extract was profiled and its allergenic potency was examined against patient's sera. Proteins having strong immunoreactivity with patient's IgE were characterized using peptide mass fingerprinting (PMF). Tropomyosin (TM) (33kDa), myosin light chain (20kDa), and arginine kinase (40kDa)were identified as allergenic proteins. Tropomyosin, the most abundant and potent allergen, was purified using ionexchange chromatography for de novo sequencing experiments. Using bottom up tandem mass spectrometry, the full amino acid sequence was achieved by a combination of matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) tandem mass spectrometry (QqToF). Myosin light chain and arginine kinasewere also characterized, and their related peptideswere de novo sequenced using the same approach. The immunological reactivity of the crude prawn extracts and purified TM samples were analyzed using a large number of patients' sera. A signature peptide was assigned for theTMprotein for future quantification work of black tiger prawnTMlevels in different matrices (i.e. water, air, food) in the seafood industry. © 2010 John Wiley & Sons, Ltd.