Development of microreactors with surface-immobilized biocatalysts for continuous transamination.

Area of Science:

• Biocatalysis and Enzyme Engineering
• Chemical Process Development
• Microfluidics and Reaction Engineering

Background:

• Optically pure compounds are crucial in industry, driving demand for efficient chiral amine synthesis.
• ω-transaminases (ATA) are key biocatalysts for synthesizing chiral amines.
• Fast and cost-effective process development, including biocatalyst immobilization, is vital for industrial implementation.

Purpose of the Study:

• To develop microscale reactors for high-throughput process development of ATA-catalyzed reactions.
• To evaluate different immobilization strategies for ATA in microreactors.
• To assess the performance and stability of immobilized ATA for industrial applications.

Main Methods:

• Surface immobilization of wild type ATA (ATA-wt) and engineered N-SBM-ATA-wt on microchannel surfaces using silanization and glutaraldehyde bonding.
• Utilizing microscale reactors coupled with quenching systems and at-line HPLC analytics.
• Employing engineered E. coli cells overexpressing ATA for immobilization.

Main Results:

• Microreactors enabled efficient immobilization of E. coli cells and N-SBM-ATA-wt.
• Achieved high volumetric productivity up to 14.42 g L⁻¹ h⁻¹ with engineered variants.
• Demonstrated in-operando characterization of biocatalyst stability in miniaturized reactors.

Conclusions:

• Microscale reactors serve as effective platforms for high-throughput process development of biocatalysts.
• Engineered ATA and whole-cell biocatalysts show significant potential for industrial chiral amine synthesis.
• The developed system facilitates efficient biocatalyst immobilization and stability assessment for scale-up.