# Identifying the genetic basis of strain specific antimicrobial activity against a major foodborne pathogen

> **NIH NIH R03** · UNIVERSITY OF ARIZONA · 2024 · $76,750

## Abstract

Project Summary
Microbial communities are dynamic and are influenced by a broad suite of biotic and abiotic factors.
One of the most important factors providing structure to microbiomes are direct interactions among
members of these communities, and therefore a deeper understanding of the molecules produced by
and which affect other microbes as well as resistance mechanisms to these molecules will greatly inform
our ability to engineer microbial communities. Bacteriocins are molecules produced by bacterial cells
that are thought to specifically target different strains of the same species or closely related species.
Tailocins are a subset of bacteriocins coopted from phage tails, which are durable, possess highly
specific killing activities, maintain one-hit-one-kill dynamics, and appear to be effective prophylactic
treatments for preventing bacterial invasion of plants. The Baltrus lab has broadly characterized a class
of phage derived bacteriocins produced by the plant pathogen Pseudomonas syringae as well as other
Pseudomonads, and we show that the host range of some of these molecules is broader than originally
thought in that they can target some human pathogens that are often found associated with plants.
Specifically, we have discovered that Pseudomonas sp. 43A maintains tailocin-like killing activity
specifically against E. coli O157:H7 and not against a variety of other E. coli or Salmonella strains.
Experiments within this proposal will confirm and characterize the genetic basis of this tailocin-like
killing of E. coli O157:H7. Overall, experiments within this proposal could allow for fine scale
engineering to enable tailocins to specifically and effectively target human pathogens associated with
plants while avoiding off target effects associated with other agricultural antimicrobial treatments.

## Key facts

- **NIH application ID:** 10786813
- **Project number:** 1R03AI180493-01
- **Recipient organization:** UNIVERSITY OF ARIZONA
- **Principal Investigator:** David A Baltrus
- **Activity code:** R03 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $76,750
- **Award type:** 1
- **Project period:** 2023-12-01 → 2025-10-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10786813

## Citation

> US National Institutes of Health, RePORTER application 10786813, Identifying the genetic basis of strain specific antimicrobial activity against a major foodborne pathogen (1R03AI180493-01). Retrieved via AI Analytics 2026-05-28 from https://api.ai-analytics.org/grant/nih/10786813. Licensed CC0.

---

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