Bacterial Consumption of T4 Phages

Area of Science:

• Microbiology
• Environmental Science
• Virology

Background:

• Bacteria consume diverse organic matter, yet viral consumption remains largely uncharacterized.
• Viruses are ubiquitous, but their role in active biocontrol is not well-established.
• Mechanisms of viral biomass reintegration into trophic cycles are unknown.

Purpose of the Study:

• To investigate bacterial predation on viruses.
• To explore the potential of bacteria as a biocontrol agent against viruses.
• To elucidate the mechanisms of viral consumption by bacteria.

Main Methods:

• Utilized 13C-labelled T4 phages to track viral consumption and bacterial DNA increase.
• Employed 12C T4 phages as a control in wastewater sludge experiments.
• Isolated bacterial strains to confirm phage as a sole nutrient source.

Main Results:

• Observed a decrease in plaque-forming units and a concomitant increase in bacterial DNA density.
• Identified Aeromonadacea as the primary predators of T4 phages in wastewater sludge.
• Demonstrated significant in situ bacterial growth fueled by phage consumption.
• Confirmed an isolated Aeromonas strain utilizes T4 phages for carbon, nitrogen, and phosphorus.

Conclusions:

• Bacterial species actively consume bacteriophages in situ.
• Phage predation by bacteria represents a widespread and underestimated biocontrol mechanism.
• Harnessing bacterial potential could limit the spread of harmful viruses in environments like water and the gut.