Fragmented α-Amylase into Microporous Metal-Organic Frameworks as Bioreactors

Area of Science:

• Biotechnology
• Materials Science
• Enzyme Engineering

Background:

• Enzyme immobilization is crucial for biocatalysis, but large enzymes pose challenges for porous materials like metal-organic frameworks (MOFs).
• Traditional immobilization methods struggle with enzyme size exclusion and structural integrity within microporous MOFs.

Purpose of the Study:

• To develop an efficient strategy for preparing an α-amylase bioreactor using metal-organic frameworks (MOFs).
• To overcome the size limitations of immobilizing large enzymes within the micropores of MOFs.
• To create a reusable and highly active biocatalytic system for carbohydrate production.

Main Methods:

• Disruption of α-amylase tertiary and quaternary structures using urea, dithiothreitol (DTT), and iodoacetamide (IAA).
• Penetration of unfolded α-amylase into microporous MOFs, specifically evaluating UiO-66.
• Characterization of the fragmented α-amylase@MOF bioreactor and assessment of its catalytic performance.

Main Results:

• Successful preparation of fragmented α-amylase@MOF bioreactors by unfolding the enzyme.
• UiO-66 demonstrated optimal pore size matching for the fragmented α-amylase α-helix.
• The bioreactor achieved high yields of maltose (>80% conversion) and maintained activity over 15 reuse cycles.

Conclusions:

• A facile strategy for creating enzyme@MOF bioreactors was established by unfolding large enzymes.
• The fragmented α-amylase@UiO-66 bioreactor shows significant potential for efficient and reusable biocatalysis.
• This approach overcomes previous limitations in immobilizing large enzymes within MOFs for practical applications.