Abstract: Myosin was extracted from tilapia muscle, and the effect of 5 mmol/L L-lysine on the turbidity, solubility, molecular structure and shape of myosin (2.0 mg/mL) was studied in low ionic strength (0–150 mmol/L KCl) solutions. The L-lysine-induced solubilization behavior and mechanism of myosin were analyzed. Results showed that myosin molecules were assembled into filaments with low solubility under low ionic strength conditions. L-Lysine could significantly decrease the turbidity of myosin dispersion (P < 0.05), and inhibit the aggregation of protein molecules, thereby having an obvious solubilizing effect on L-lysine. Surface hydrophobicity of soluble myosin was increased, and α-helix content was decreased (P < 0.05). Compared with the pH shifting group, the solubilization of myosin by L-lysine was more remarkable in 1–40 mmol/L KCl solution. The absolute zeta potential of myosin treated with L-lysine was increased, leading to the dissociation of myosin filaments.

Key words: myosin, L-lysine, low ionic strength, solubility, solubilization mechanism