# Modulation of gut bacteria-derived host metabolites

> **NIH NIH K08** · STANFORD UNIVERSITY · 2020 · $135,258

## Abstract

Project Summary/Abstract
Crohn's disease and Ulcerative Colitis, collectively referred to as inflammatory bowel disease (IBD) are
devastating diseases that affect over one million people in the US. Current IBD therapies target the immune
system, leaving patients susceptible to opportunistic infections. Therefore, the discovery of new therapeutics for
IBD is an important priority. Recent studies have discovered several metabolites produced exclusively by gut
bacteria that exert immunomodulatory effects at the mucosal interface. Indolepropionic acid (IPA) has emerged
as the most exciting compound thus far in that it specifically engages host receptors and protects from
experimental colitis in mice. This compound is produced by a discrete number of strictly anaerobic gut
commensal bacteria including Clostridium sporogenes. Strategies to modulate levels of IPA could represent a
new adjunct therapy for IBD patients. Despite the broad interest in this compound, the specific biochemical
pathways involved in its synthesis are entirely unknown.
Our long-term objective is to develop new therapeutic strategies aimed at controlling the metabolic output of gut
bacterial communities. The goal of the current proposal is to unravel the biochemical pathway for IPA
synthesis in C. sporogenes and to establish methods for increasing its production within the gut. The specific
aims are to: 1) Determine how metabolic engineering and nutrient availability influence IPA production by
Clostridium sporogenes in vitro, and 2) Develop strategies for ecosystem restructuring to promote therapeutic
IPA production in the mouse gut. We will leverage newly developed genetic tools to understand how and why
gut bacteria produce IPA. Using this information, we will assemble synthetic microbial communities in the gut
designed to promote colonization by IPA producing bacteria. Finally, we will use these communities to reprogram
IPA levels in mice and test whether we can protect against experimental colitis. The outcomes of these aims will
represent the first steps toward controlling the metabolic output of gut bacteria for clinical benefit. This knowledge
will be broadly relevant to modulating other microbial metabolites implicated in human diseases such as uremia,
liver disease, cardiovascular disease, and autism.
The proposed research is part of a mentored career development plan to achieve an academic career
studying host-microbe interactions. The principal investigator is a PhD-trained microbiologist with training in
Clinical Pathology. My goal as an independent scientist is to understand the microbial contribution to the
biochemical inventory within our body. The mentor for this project is Dr. Justin Sonnenburg, a pioneer in studying
the contribution of gut bacteria to host biology. The career development plan includes a research advisory board,
a career development committee, seminars in microbial physiology, formal coursework in bacterial genetics and
ecology, and presentations...

## Key facts

- **NIH application ID:** 9841391
- **Project number:** 5K08DK110335-03
- **Recipient organization:** STANFORD UNIVERSITY
- **Principal Investigator:** Dylan Dodd
- **Activity code:** K08 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $135,258
- **Award type:** 5
- **Project period:** 2018-03-08 → 2022-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9841391

## Citation

> US National Institutes of Health, RePORTER application 9841391, Modulation of gut bacteria-derived host metabolites (5K08DK110335-03). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9841391. Licensed CC0.

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