# Environmental modulation of microbial conflict and cooperation

> **NIH NIH R01** · MASSACHUSETTS INSTITUTE OF TECHNOLOGY · 2020 · $296,391

## Abstract

Project Summary: Environmental modulation of microbial conflict and cooperation
Microorganisms have tremendous impacts on human health, from the often beneficial effects of the gut
microbiome to the deleterious effects of pathogenic bacteria. A key determinant of these health outcomes is
the interactions within the microbial community and between the community and the environment of the
host. Examples include the collective inactivation of antibiotics by a bacterial population and exchange of
nutrients within the microbial population. Despite the clear importance of these interactions, our ability to
manipulate them to improve health is often rudimentary. A major obstacle to improved understanding of
microbial communities has been the lack of feedback between theoretical models in ecology and
experimentally tractable microbial model communities. I propose to use quantitative experiments of
microbial communities to explore how environmental changes can transform the consequences of a
particular interaction within the community.
 Over the course of this grant we will take a bottom-up approach to explore how environmental
changes will influence three canonical forms of interactions within a microbial community. First we will
explore simple cooperation within a population, and in particular whether this cooperation can limit the
ability of the population to survive deteriorating environments. As a model system we will explore whether
budding yeast can evolve to survive high salt concentrations, and how this survival probability depends
upon whether the sugar source requires cooperation within the population. Next we will study how nutrient
concentration modulates the properties of a mutualism in which two strains of micro-organism are cross-
feeding essential nutrients. We will demonstrate that increasing nutrient concentrations can transform the
interaction from a beneficial mutualism into a parasitism, where one partner is actually harmed by the other.
Finally, we will study a situation in which two populations are each cooperating with themselves but in a way
that harms the other population. We will demonstrate that in low nutrient environments these populations
can coexist because population sizes are sufficiently low to prevent excessive negative interaction, but as
nutrient concentrations increase there can actually be a loss of diversity.
 My goal is to transform our understanding of microbial communities while also developing concrete
model communities that can be used to quantitatively test ideas from theoretical ecology. The fields of
ecology and biomedicine have had little exchange of ideas over the last thirty years, but I believe that many
key challenges to human health will require ecological approaches. For example, many of the concepts
developed in microbial community ecology may be useful to researchers studying other interacting
populations, from the immune system to cancer.

## Key facts

- **NIH application ID:** 9896836
- **Project number:** 5R01GM102311-08
- **Recipient organization:** MASSACHUSETTS INSTITUTE OF TECHNOLOGY
- **Principal Investigator:** Jeff Gore
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $296,391
- **Award type:** 5
- **Project period:** 2013-04-01 → 2022-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9896836

## Citation

> US National Institutes of Health, RePORTER application 9896836, Environmental modulation of microbial conflict and cooperation (5R01GM102311-08). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9896836. Licensed CC0.

---

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