Antibiotic-Facilitated Predation Clears Resistant Bacteria
Combining colistin with predatory bacteria restores the ability of B. bacteriovorus to eradicate multidrug-resistant pathogens.
Updated on Oct. 23, 2026 in Life Sciences
Researchers have demonstrated that pairing the predator bacterium Bdellovibrio bacteriovorus with the antibiotic colistin effectively clears multidrug-resistant Gram-negative pathogens. This research-stage study found that the combination treatment significantly enhances predator attachment and survival outcomes in an animal model.
Why it matters
As multidrug-resistant bacteria render standard treatments less effective, leveraging biological predators to sensitize pathogens to remaining antibiotics offers a new approach to overcoming persistent infections. This method repurposes existing drugs to improve the performance of live therapeutic agents.
Combination therapy with 8 mg/L colistin produced a 6.75-log reduction in viable prey by 6 hours and depleted mcr-1 abundance by 99.96%. Transient pretreatment increased predator attachment twofold and bdelloplast formation 1.56-fold compared to baseline.
The players
Bdellovibrio bacteriovorus
A predatory bacterium that survives by invading and consuming Gram-negative pathogens.
The details
The treatment works by using colistin to increase the outer-membrane permeability of the target bacteria, which facilitates more efficient attachment by B. bacteriovorus. Once attached, the predator forms a bdelloplast—a specialized structure where the predator grows inside the prey—before consuming the pathogen from the inside out. This effect is independent of inner-membrane disruption, allowing the predator to remain viable while the antibiotic primes the prey for easier entry.
Timeline
6 hours: The combination treatment achieved a 6.75-log reduction in viable prey.
24 hours: Pathogen counts were reduced below detectable levels.
Day 3: Survival rates in Galleria mellonella reached 50 percent.
The Tech Race
This research advances the field of living therapeutics by pairing biological agents with conventional antibiotics to overcome multi-drug resistance. It represents a departure from traditional drug development, focusing instead on optimizing the synergy between live predators and residual antibiotic activity.
This development is currently limited to laboratory and animal-model research and is not available for clinical use. It serves as a proof-of-concept for future therapies that may eventually address severe infections resistant to standard antibiotics.
The takeaway
This study underscores the potential for pairing living therapeutics with conventional drugs to bypass pathogen defense mechanisms. Researchers and clinicians should monitor subsequent trials for data on predator persistence and systemic safety profiles in mammalian models.
Further reading
Explore the latest developments in medical innovation within the Life Sciences section.
Source note: This article includes information reported by Nature.
