Broad-Host-Range Phages: Nature’s Ubiquitous Virus Hunters Across Ecosystems

Broad-Host-Range Phages: A Hidden Force in Microbial Ecosystems

Bacteriophages—viruses that infect bacteria—are the most abundant biological entities on Earth. Traditionally, phages were thought to infect specific bacterial hosts, but recent findings reveal that broad-host-range (BHR) phages are widespread across ecosystems, from soil to oceans to the human gut.

The study used metagenomic datasets and virus-host prediction tools to map the diversity, distribution, and ecological roles of BHR phages globally.

Key Findings: Phages Without Boundaries

1. Widespread Across Ecosystems

BHR phages were detected in:

Marine and freshwater environments
Soil and rhizosphere ecosystems
Animal and human microbiomes

Their presence in diverse habitats suggests they play a critical role in microbial population dynamics and nutrient cycling.

2. Shaping Microbial Community Structure

BHR phages can infect multiple bacterial lineages, influencing:

Bacterial diversity through top-down predation
Horizontal gene transfer, spreading beneficial genes across microbial communities

3. Role in Global Biogeochemical Cycles

By lysing bacteria, BHR phages release organic matter and nutrients back into the ecosystem, impacting carbon and nitrogen cycles at a planetary scale.

4. Potential for Phage Therapy

Their ability to target multiple bacterial hosts makes BHR phages promising candidates for:

Treating multi-species bacterial infections
Controlling harmful algal blooms
Engineering microbiomes for health and agriculture

Why It Matters for Science and Society

The discovery of abundant BHR phages challenges long-held assumptions about virus-host specificity and opens new avenues in:

Environmental microbiology
Synthetic biology
Infectious disease control

Harnessing these phages could transform phage therapy and microbiome engineering in the future.

Conclusion: Phages as Global Microbial Architects

This research highlights broad-host-range bacteriophages as key ecological players with global impacts on microbial networks and ecosystem functions.

Their ubiquity and versatility make them critical to understanding microbial evolution, environmental processes, and future biotechnological innovations.

Reference

Bignaud, A., Conti, D. E., Thierry, A., Serizay, J., Labadie, K., Poulain, J., Cheny, O., Colón-González, M., Debarbieux, L., Guerrero-Osornio, M., Helaine, S., Hill, P., Le Tinier, G., Millot, G. A., Morales, L., Parada, A., Riera, N., Iraola, G., Koszul, R., & Marbouty, M. (2025). Phages with a broad host range are common across ecosystems. Nature Microbiology. https://doi.org/10.1038/s41564-025-02108-2