# Impacts of Borrelia burgdorferi Gac protein on infectivity and regulation of virulence protein expression

> **NIH NIH R21** · UNIVERSITY OF KENTUCKY · 2024 · $222,109

## Abstract

ABSTRACT
We recently found that the Gac DNA-binding protein of Borrelia burgdorferi, the Lyme disease bacterium,
functions as a transcriptional repressor of the essential ospC gene. RNA-sequencing (RNA-Seq) analyses of a
gac mutant revealed that Gac impacts levels of transcripts of several other virulence-associated proteins,
including the alternative sigma factors RpoN and RpoS. Prior studies demonstrated that RpoN is required for
expression of RpoS, and both are required for mammalian infection. The planned studies will further
investigate the functions of Gac in the Lyme disease spirochete, including its impacts on mammalian and tick
infection and molecular characterization of Gac's impacts on rpoN expression. Results of these studies will
provide important insights on regulatory mechanisms that control virulence of the Lyme disease spirochete and
help identify key components for development of improved, specific antibacterials.

## Key facts

- **NIH application ID:** 10862936
- **Project number:** 1R21AI182568-01
- **Recipient organization:** UNIVERSITY OF KENTUCKY
- **Principal Investigator:** Brian Stevenson
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $222,109
- **Award type:** 1
- **Project period:** 2024-06-01 → 2026-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10862936

## Citation

> US National Institutes of Health, RePORTER application 10862936, Impacts of Borrelia burgdorferi Gac protein on infectivity and regulation of virulence protein expression (1R21AI182568-01). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10862936. Licensed CC0.

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