Chemoenzymatic Assembly of Isotopically Labeled Folates

Area of Science:

• Biochemistry
• Organic Synthesis
• Enzymology

Background:

• Pterin-containing natural products are crucial for biological functions.
• Existing in vitro synthesis methods for these compounds are inefficient and complex.

Purpose of the Study:

• To develop an efficient and accessible chemoenzymatic synthesis for producing labeled dihydrofolates (H2F).
• To enable the study of enzymatic mechanisms using isotope effects.

Main Methods:

• A 14-step, one-pot chemoenzymatic synthesis was employed.
• Labeled (13C and 15N) dihydrofolates were synthesized from glucose, guanine, and p-aminobenzoyl-l-glutamic acid.

Main Results:

• The synthesis achieved an average yield of >91% per step.
• Only a single purification step was required, simplifying the process.
• Heavy-atom isotope effects were measured for dihydrofolate reductase, revealing a stepwise mechanism.

Conclusions:

• The developed chemoenzymatic synthesis is highly efficient for producing labeled dihydrofolates.
• This method facilitates the study of enzyme mechanisms and the production of other natural compounds.
• The approach has broad applications in nutritional, medical, and cell-biological research.