Carbon monoxide-producing probiotic Escherichia coli attenuates HSV-1 skin disease
<h2>Summary</h2> Persistent infections and inflammatory diseases remain major health challenges due to their prevalence and limited prophylactic and therapeutic options. Heme oxygenases (HOs) degrade heme into bioactive molecules, including carbon monoxide (CO), a traditionally toxic gas yet naturally produced in mammals to regulate inflammation. Here, we investigated whether bacterial CO production via bacterial heme oxygenase ChuS, present in commensal <i>Escherichia coli</i>, could confer prophylactic effects against HSV-1 skin infection. Oral administration of <i>E. coli</i> Nissle 1917 (EcN) increased serum carboxyhemoglobin in a ChuS-dependent manner. Moreover, isolated commensal <i>E. coli</i> strains carrying <i>chuS</i>, but lacking the genotoxin colibactin, enhanced CO levels and reduced HSV-1 severity. Combined administration of these strains elicited a trend toward reduced disease severity and a significant reduction in viral load compared to controls. These findings identify ChuS as a microbial driver of CO-mediated anti-inflammation and highlight probiotic <i>E. coli</i> as a safe, natural platform for CO delivery.
Authors
- Pablo A. González (ORCID: https://orcid.org/0000-0001-7709-6870)
- Susan M. Bueno (ORCID: https://orcid.org/0000-0002-7551-8088)
- Yaneisi Vázquez (ORCID: https://orcid.org/0000-0003-4299-478X)
- Omar P. Vallejos (ORCID: https://orcid.org/0000-0002-5203-7062)
- Javiera Sepúlveda-Alfaro
- Felipe Melo-González (ORCID: https://orcid.org/0000-0002-3711-2407)
- Eduardo I. Tognarelli (ORCID: https://orcid.org/0000-0003-0038-0704)
- Alejandro Piña-Iturbe (ORCID: https://orcid.org/0000-0001-6190-9494)
- Manuel Álvarez-Lobos (ORCID: https://orcid.org/0000-0002-1245-8479)
- Isidora D. Suazo (ORCID: https://orcid.org/0000-0001-8274-7471)
- Irenice Coronado-Arrázola (ORCID: https://orcid.org/0000-0001-5418-2768)
- Esteban Caamaño
- Franco Bassi
- Patricia Pereira-Sánchez
- Pedro H. Silva
- José Acevedo-López
- Francisco B. Quero
- Aniela Woźniak
- Pablo Reyes-Bustos
- Valentina A. Vergara-Espinoza
- Alexis M. Kalergis
- Javiera P. Bahamondes-Abrigo
- Lucas Vásquez-Herrera
- Alejandra Mateluna
- Sofía Campos-Gajardo
- Guillermo Hoppe-Elsholz
- Valentina Scaff
Institutions
- Pontificia Universidad Católica de Chile (CL)
- Universidad Andrés Bello (CL)
- Clínica MEDS (Chile) (CL)
- Center for Climate and Resilience Research (CL)
- Millennium Institute on Immunology and Immunotherapy (CL)
Publication Details
- Journal
- iScience
- Published
- 2026-05-22
- DOI
- https://doi.org/10.1016/j.isci.2026.116042
- Primary Topic
- Heme Oxygenase-1 and Carbon Monoxide
- Type
- article
- Field-Weighted Citation Impact
- 0.00