Tyrosinase Cross-Linked PEG Hydrogels with DAT and DATT as Artificial Substrates: Design, Structure, and Functions

Area of Science:

• Biomaterials Science
• Enzyme Catalysis
• Polymer Chemistry

Background:

• Enzyme-catalyzed hydrogel synthesis offers sustainability but lacks mechanistic understanding.
• Complex reactions hinder mechanistic insights and biomedical applications of enzyme-derived hydrogels.

Purpose of the Study:

• To identify efficient artificial substrates for mushroom tyrosinase (mTyr) to synthesize hydrogels.
• To elucidate the mechanism of mTyr-catalyzed hydrogel formation and characterize material properties.
• To evaluate the potential of these hydrogels for controlled release and in vitro biocompatibility.

Main Methods:

• Computational methods (molecular docking, MM-GBSA) to identify artificial substrates.
• Synthesis of desaminotyrosine (DAT) and desaminotyrosyltyrosine (DATT) functionalized star-shaped oligoethylene glycol (sOEG) hydrogels.
• Characterization of hydrogel properties (mesh size, release kinetics) and cell culture studies.

Main Results:

• DAT and DATT were more efficiently converted by mTyr than tyrosine.
• Hydrogel properties were tunable based on sOEG molecular weight, substrate, and mTyr concentration.
• Hydrogels demonstrated controlled release capabilities and inertness in cell culture studies.

Conclusions:

• Developed novel, efficient enzyme-catalyzed hydrogels using DAT/DATT substrates.
• Provided fundamental insights into mTyr-mediated hydrogel formation.
• These hydrogels are promising for in situ applications and further biomedical exploration.