# Application of a high throughput platform for screening directed evolution libraries

> **NIH NIH R21** · UNIVERSITY OF CALIFORNIA SANTA CRUZ · 2023 · $65,926

## Abstract

Parent award abstract. The controlled evolution of proteins in the laboratory is a valuable biomedical tool for
accessing biomolecules for industrial, therapeutic and research applications. This process, also known as
directed evolution, allows one to employ the specificity and selectivity that Nature imbues within its privileged
biomolecules to construct unnatural products that would otherwise be inefficient or laborious to generate
chemosynthetically. While this process is incredibly powerful, an existing bottleneck is the subsequent
screening of the resulting variants for these high value products. The directed evolution process typically
generates hundreds to thousands of mutants or library members for biochemical analysis. In some cases,
fluorescent reporter systems or bioactivity assays can be employed as a general biochemical readout,
however, this does not inform on specific chemical transformations towards diverse small molecule targets.
When high value chemical products are the subject of these directed evolution experiments, researchers
employ multiple orthogonal analytical techniques, including: high performance liquid chromatography (HPLC);
gas chromatography (GC); mass spectrometry (MS); and nuclear magnetic resonance (NMR). This becomes
time and infrastructure intensive when thousands of variants need to be evaluated; even if variants are pooled
in curated groups, considerable effort is needed for chromatographic assessment. Additionally, many of these
methodologies may not be sensitive or specific enough to necessitate detection of low titer production of the
desired product(s). Based on these shortcomings of the screening platforms, we are proposing to leverage our
labs’ existing strengths to develop a high-throughput, specific, and sensitive mass spectrometry platform to
screen directed evolution libraries for bioactive chemical products without chromatographic separation. The
McKinnie lab has expertise in synthetic chemistry and biochemistry and has specifically worked on the α-
ketoglutarate-dependent dioxygenase enzyme to construct neuroactive kainic acid on the gram scale. The
Sanchez lab has expertise in natural product discovery and mass spectrometry techniques such as imaging
mass spectrometry and tandem mass spectrometry. These respective strengths will allow us to develop an
innovative pipeline for screening thousands of directed evolution library members to prioritize variants that
direct the chemistry towards kainoid-ring glutamate receptor agonists and antagonists. Our pipeline will allow
for unprecedented measurements in chemical specificity and be broadly applicable for any groups looking to
conduct directed evolution.
 · Current directed evolution screening platforms are time-consuming or low throughput
 · The combined expertise of our team is highly interdisciplinary
 · Mass spectrometry and trapped ion mobility spectrometry allow for high dimensionality measurements
 directly from mutant colonies without relianc...

## Key facts

- **NIH application ID:** 10818241
- **Project number:** 3R21GM148870-01S1
- **Recipient organization:** UNIVERSITY OF CALIFORNIA SANTA CRUZ
- **Principal Investigator:** Laura Margaret Sanchez
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2023
- **Award amount:** $65,926
- **Award type:** 3
- **Project period:** 2023-01-01 → 2024-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10818241

## Citation

> US National Institutes of Health, RePORTER application 10818241, Application of a high throughput platform for screening directed evolution libraries (3R21GM148870-01S1). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10818241. Licensed CC0.

---

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