Engineering of phenylacetaldehyde reductase for efficient substrate conversion in concentrated 2-propanol

Area of Science:

• Biocatalysis and enzyme engineering
• Organic chemistry
• Industrial biotechnology

Background:

• Phenylacetaldehyde reductase (PAR) catalyzes the conversion of aryl ketones and 2-alkanones to chiral alcohols.
• 2-Propanol serves as both a solvent and hydrogen donor for cofactor regeneration in PAR-catalyzed reactions.
• Improving enzyme efficiency at high substrate and 2-propanol concentrations is crucial for industrial scalability.

Purpose of the Study:

• To enhance the conversion efficiency of Phenylacetaldehyde reductase (PAR) when using high concentrations of substrates and 2-propanol.
• To adapt PAR for industrial applications requiring robust enzymatic processes.

Main Methods:

• Construction and screening of a PAR mutant library.
• Identification and combination of advantageous mutations through directed evolution.
• Enzyme adaptation for high substrate and concentrated 2-propanol conditions.

Main Results:

• A single round of selection and manual combination of mutations successfully improved PAR's performance.
• Engineered PAR demonstrated enhanced conversion efficiency with concentrated substrates and 2-propanol.
• The adapted PAR enzyme is suitable for industrial-scale biocatalytic processes.

Conclusions:

• Enzyme engineering via directed evolution and mutation rearrangement is effective for optimizing biocatalysts.
• This strategy significantly improves PAR's utility for producing chiral alcohols from high substrate loads.
• The developed method offers broad applicability for engineering enzymes for various industrial applications.