# Engineering radical enzymes for asymmetric olefin hydroalkylation

> **NIH GM R35** · MICHIGAN STATE UNIVERSITY · 2026 · $335,924

## Abstract

PROJECT SUMMARY: The synthesis of biologically active molecules through selective C–C bond-forming
reactions is central to the discovery of new therapeutics. Though forging C–C bonds is often more challenging
at C(sp3)-centers than C(sp2)-centers, especially when new stereocenters emerge, clinical success is correlated
with sp3-richness. Consequently, developing new methods to rapidly generate complex, sp3-rich compounds
from simple starting materials presents an opportunity for synthetic innovation to accelerate the discovery of new
medicines. Nature constructs bioactive molecules using enzymes to form C(sp3)–C(sp3) bonds stereoselectively,
and some of these enzymes have been harnessed for pharmaceutical synthesis. However, Nature offers many
synthetically useful enzymes that have not been explored for use in biocatalysis. Here, hydroalkylase enzymes
will be developed for synthetic applications to form new intermolecular C(sp3)–C(sp3) bonds from simple, achiral
starting materials. Enzymatic hydroalkylation can directly activate C–H bonds without pre-functionalization and
has the potential to form up to three contiguous stereocenters in one step. Glycyl radical enzyme (GRE)
hydroalkylases can convert C(sp3)–H bonds directly into new C–C bonds using simple amino acid-based
radicals. The potential to use GRE hydroalkylases for biocatalysis has been noted for decades, but an inability
to install the amino acid-based radicals in vitro severely limited their application. Recently, a platform to overcome
this limitation was developed, enabling the generation of amino acid-based radicals within purified enzyme.
Theme 1 of this proposal builds on this advance to investigate the native substrate scopes of two GRE
hydroalkylases: one that functionalizes toluene and one that functionalizes n-hexadecane. These two wild-type
enzymes will be used as starting points to engineer variants through genetic manipulation to broaden substrate
scope, enhance selectivity, and discover non-

## Key facts

- **NIH application ID:** 11270000
- **Project number:** 1R35GM162132-01
- **Recipient organization:** MICHIGAN STATE UNIVERSITY
- **Principal Investigator:** Mary Catherine Andorfer
- **Activity code:** R35 (R01, R21, SBIR, etc.)
- **Funding institute:** GM
- **Fiscal year:** 2026
- **Award amount:** $335,924
- **Award type:** 1
- **Project period:** 2026-04-01T00:00:00 → 2031-03-31T00:00:00

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/11270000

## Citation

> US National Institutes of Health, RePORTER application 11270000, Engineering radical enzymes for asymmetric olefin hydroalkylation (1R35GM162132-01). Retrieved via AI Analytics 2026-07-08 from https://api.ai-analytics.org/grant/nih/11270000. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*