Transaminase-catalyzed sequential hydrodefluorinations of perfluorinated methylene groups

Area of Science:

• Biocatalysis and Environmental Biotechnology
• Enzyme Engineering and Biotransformation
• Fluorochemical Degradation

Background:

• Recalcitrant fluorochemicals pose significant environmental challenges.
• Enzymatic activation of C-F bonds, especially in perfluorinated compounds, is difficult due to bond strength.
• Biodegradation of polyfluorinated compounds requires novel enzymatic strategies.

Purpose of the Study:

• To develop a biocatalytic method for degrading difluorinated fused-ring ketones.
• To engineer transaminases for a new-to-nature hydrodefluorination reaction.
• To provide insights into the mechanism of enzymatic defluorination.

Main Methods:

• Engineering of transaminases for hydrodefluorination activity.
• Biocatalytic degradation assays using difluorinated fused-ring ketones.
• Mechanistic studies involving transamination steps and amine donors (e.g., 2-PrNH2).

Main Results:

• Successful demonstration of a new-to-nature hydrodefluorination reaction catalyzed by engineered transaminases.
• High defluorination efficiency achieved for difluorinated fused-ring ketones.
• Confirmation of a reversible transamination step as the initial catalytic event.

Conclusions:

• Engineered transaminases can effectively catalyze the biodegradation of difluorinated ketones.
• The developed biocatalytic strategy offers a promising route for polyfluorinated compound degradation.
• This research contributes to environmental sustainability through novel enzymatic solutions.