LAUSR

BACKGROUND T-2 toxin (T-2) is a potent mycotoxin and a common contaminant of aquatic animal feed, posing a serious risk to the health and aquatic animals. We investigated the effect of T-2 on shrimp muscle proteins using proteomics and conventional biochemical methods. Shrimp were fed a diet containing T-2 at 0 - 12.2 mg kg-1 for 20 days, and changes to the muscle protein composition, ATPase activities, and the sulfhydryl content and hydrophobicity of actomyosin were determined. A proteomics study of the proteins were conducted with SDS-PAGE, 2D electrophoresis and MALDI-TOF-TOF MS. RESULTS Exposure to T-2 markedly affected the muscle protein composition of shrimp in a concentration-responsive manner that displayed a diphasic effect. At the low T-2 concentration (1.2 mg kg-1 ), the levels of three major muscle proteins (myofibrillar, sarcoplasmic and stroma) increased, but at higher concentrations they declined progressively. T-2 exposure also led to a breakdown of muscle proteins as evidenced by increases in alkali-soluble protein and the surface hydrophobicity of actomyosin. Thirty differentially-expressed proteins were detected, 12 of which showing a concentration-response relationship to T-2 exposure. Among them, eleven homologous proteins were identified by mass spectrometry, with several being key enzymes in energy metabolism. CONCLUSION This study demonstrated that T-2 exposure at medium to high-concentrations could significantly affect the protein composition and quality of shrimp muscle, and potentially some of its key metabolisms. One of the arginine kinases (spot 27) was particularly responsive to T-2 and could potentially be used as a biomarker protein for T-2 intoxication by shrimp. This article is protected by copyright. All rights reserved.