Light-driven decarboxylative deuteration enabled by a divergently engineered photodecarboxylase

Area of Science:

• Biocatalysis
• Enzymology
• Organic Chemistry

Background:

• Enzymatic methods for deuterium incorporation are limited.
• Chemical methods for C-D bond formation are well-established but lack enzymatic alternatives.

Purpose of the Study:

• To develop an enzymatic method for deuterium incorporation into carboxylic acids.
• To expand the substrate scope of enzymatic deuteration through protein engineering.

Main Methods:

• Photodecarboxylase from Chlorella variabilis NC64A (CvFAP) was used for decarboxylative deuteration.
• Deuterium oxide (D2O) was employed as the deuterium source.
• Focused Rational Iterative Site-specific Mutagenesis (FRISM) was used for protein engineering.

Main Results:

• CvFAP catalyzed the decarboxylative deuteration of over 40 carboxylic acid examples, including various chain lengths, racemic substrates, and bulky cyclic acids.
• Mutant CvFAP enzymes showed improved substrate scope compared to wild-type (WT) CvFAP.
• Enantiocomplementary kinetic resolution of racemic acids was achieved, yielding chiral deuterated products.
• Molecular dynamics (MD) simulations provided insights into enhanced catalytic activity and stereoselectivity.

Conclusions:

• A novel enzymatic approach for decarboxylative deuteration using CvFAP was established.
• Protein engineering successfully broadened the substrate scope and enabled the synthesis of chiral deuterated compounds.
• This method offers a new tool for incorporating deuterium, particularly for producing chiral molecules.