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Updated: May 19, 2026
09:49
Investigation of Microbial Cooperation via Imaging Mass Spectrometry Analysis of Bacterial Colonies Grown on Agar and in Tissue During Infection
Published on: November 18, 2022
Calling a Truce: Enterococcus faecalis as a mediator between E. coli and C. albicans during polymicrobial CAUTIs
Ana Flores-Mireles1, Elsa Wongso1, Jonathan Molina1
1University of Notre Dame.
Research Square
|May 18, 2026
Summary
Enterococcus faecalis acts as a keystone species in catheter-associated urinary tract infections (CAUTIs). It facilitates the coexistence of E. coli and C. albicans, improving treatment strategies for these polymicrobial infections.
Area of Science:
- Microbiology
- Infectious Diseases
- Biofilm Research
Background:
- Polymicrobial catheter-associated urinary tract infections (CAUTIs) present a significant clinical challenge.
- Mixed biofilms, including E. faecalis, E. coli, and C. albicans, compromise antimicrobial efficacy and promote resistance.
- The cross-kingdom dynamics within CAUTIs are not well understood.
Purpose of the Study:
- To elucidate the complex interactions governing multispecies biofilms in CAUTIs.
- To understand the role of specific microbial species in driving CAUTI dynamics.
- To identify mechanisms of polymicrobial synergy and competition in the bladder.
Main Methods:
- Utilized established in vitro and in vivo CAUTI models.
- Investigated interactions between E. coli, E. faecalis, and C. albicans.
- Analyzed spatial dynamics and inter-species antagonism/coexistence.
Main Results:
- E. coli antagonizes C. albicans by limiting iron, inhibiting filamentation, and inducing cell death.
- E. faecalis acts as a keystone species, mitigating E. coli's antagonism towards C. albicans.
- E. faecalis serves as a spatial bridge, promoting co-localization of E. coli and C. albicans on the urothelium.
Conclusions:
- Mechanistic insights into polymicrobial synergy and competition in CAUTIs were revealed.
- E. faecalis plays a critical role in facilitating multispecies biofilm formation.
- Findings provide a framework for developing targeted therapies against complex CAUTIs.
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