Reductive amination: Methods for cell-free and whole-cell biocatalysis

Area of Science:

• Biocatalysis and Green Chemistry
• Organic Synthesis
• Enzyme Engineering

Background:

• Enzymatic reductive amination is a sustainable alternative to traditional chemical methods for amine synthesis.
• Transaminases (TAs), amine dehydrogenases (AmDHs), imine reductases (IREDs), and reductive aminases (RedAms) are key biocatalysts for chiral amine production.
• Protein engineering has significantly improved the performance and applicability of these enzymes.

Purpose of the Study:

• To provide comprehensive protocols for synthesizing primary, secondary, and tertiary chiral amines via enzymatic reductive amination.
• To highlight the versatility of biocatalysts in producing enantiomerically pure amines.
• To detail the application of isolated enzymes, immobilized enzymes, and whole-cell systems.

Main Methods:

• Utilizing various enzyme classes including TAs, AmDHs, IREDs, and RedAms.
• Employing protein engineering to enhance enzyme substrate scope and stability.
• Implementing immobilized enzymes and whole-cell biocatalyst systems for improved efficiency and sustainability.

Main Results:

• Demonstrated high optical purity in chiral amine synthesis.
• Expanded substrate scope and enhanced stability of biocatalysts through protein engineering.
• Successful application of enzymatic reductive amination at both laboratory and industrial scales.

Conclusions:

• Enzymatic reductive amination is a powerful, green, and selective method for chiral amine synthesis.
• Biocatalytic approaches offer sustainable and efficient routes to diverse chiral amines.
• Detailed protocols facilitate the broader adoption of these enzymatic methods in chemical synthesis.