# Bacterial Corrinoid Metabolism Across Scales: From Molecular Specificity to Community Dynamics

> **NIH NIH R35** · UNIVERSITY OF CALIFORNIA BERKELEY · 2023 · $83,527

## Abstract

Project Summary/Abstract -- No Change
Microbial communities inhabit nearly all environments on earth, including the human body, where they can
influence health in myriad ways. These communities are often composed of hundreds or more species that
form networks of metabolic interactions. Because metabolic interactions are complex and difficult to study
at a molecular level, my research program focuses on interactions involving one family of metabolites –
corrinoid cofactors – as a model to understand metabolic interactions among bacteria. Corrinoids are the vitamin
B12 family of cobalt-containing metabolites that are used as enzyme cofactors for a variety of reactions.
Corrinoids, like many amino acids, nucleobases, and other cofactors, are synthesized by only a fraction of
bacteria that use them, and therefore are considered to be shared metabolites. Corrinoids are unique in their
structural diversity, with over a dozen different forms discovered and up to eight of these forms found in
microbial community samples, including the human gut. This structural diversity is a significant factor in
microbial interactions because most bacteria are selective in the corrinoids they can use. The hypothesis
driving this work is that structurally distinct corrinoids can be used as handles to manipulate microbial
communities. Our previous NIGMS-funded research has laid the groundwork for the proposed research by
establishing experimental methods; discovering and characterizing new genes; investigating corrinoid
selectivity in enzymes, riboswitches, and bacteria; and creating a bioinformatic pipeline to predict corrinoid
metabolism in bacteria. Our long-term vision is to build on this foundation to generate a newly detailed
understanding of microbial community interactions through the study of corrinoids across scales, from molecular
mechanisms to whole community perturbations. We will achieve this goal by (1) identifying genome sequence
signatures predictive of bacterial corrinoid preferences in corrinoid-dependent enzymes and riboswitches,
with an emphasis on evolutionary approaches and (2) investigating the molecular basis of corrinoid-dependent
community dynamics by applying sequencing, culture-dependent, and genetic approaches to a model human
gut-derived enrichment culture. As a test of our ability to understand and predict corrinoid-based metabolism
and community dynamics, we will design and build bacterial strains with corrinoid-dependent metabolic
networks, as well as consortia of bacteria with predictable dynamics. This research will be
accomplished by using a combination of genetics, biochemistry, microbiology, and bioinformatics,
building upon the past research of my group. Our work on corrinoids will not only serve as a model for
microbial community interactions across systems, but may also lead to the development of new methods
to alter microbial communities for beneficial outcomes.

## Key facts

- **NIH application ID:** 10684534
- **Project number:** 3R35GM139633-03S1
- **Recipient organization:** UNIVERSITY OF CALIFORNIA BERKELEY
- **Principal Investigator:** Michiko E. Taga
- **Activity code:** R35 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2023
- **Award amount:** $83,527
- **Award type:** 3
- **Project period:** 2021-03-01 → 2026-02-28

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10684534

## Citation

> US National Institutes of Health, RePORTER application 10684534, Bacterial Corrinoid Metabolism Across Scales: From Molecular Specificity to Community Dynamics (3R35GM139633-03S1). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10684534. Licensed CC0.

---

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