Enhancing tilapia fish myosin solubility using proline in low ionic strength solution

Area of Science:

• Biochemistry
• Protein Chemistry
• Food Science

Background:

• Myosin, a key muscle protein, exhibits limited solubility under low ionic strength conditions.
• Understanding protein solubilization is crucial for food processing and biochemical applications.

Purpose of the Study:

• To investigate the efficacy of proline as a solubilizing agent for fish myosin.
• To elucidate the underlying mechanisms of proline-mediated myosin solubilization.

Main Methods:

• Solubilization of fish myosin using varying concentrations of proline (5-20 mM) in 0.1 M NaCl.
• Analysis of surface hydrophobicity and secondary structure (β-sheet content) of myosin.
• Transfer free energy measurements to assess amino acid interactions.
• Transmission electron microscopy (TEM) to visualize protein aggregates.

Main Results:

• 10 mM proline achieved over 80% solubilization of fish myosin.
• Proline significantly decreased myosin's surface hydrophobicity and increased its β-sheet structure.
• Favorable interactions were observed between proline and tyrosine/tryptophan residues.
• Proline shielded hydrophobic sites and disrupted disulfide bonds, promoting myosin oligomerization.

Conclusions:

• Proline is an effective solubilizing agent for fish myosin under low ionic strength.
• The solubilization mechanism involves proline shielding hydrophobic regions and altering protein structure.
• Chemical interactions between proline and myosin residues are central to the observed effects.