Mechanism: Engineered bacteriophages deliver matrix-degrading enzymes (dispersin B, DNase I) upon bacterial lysis, leading to a self-amplifying biofilm destruction cascade. Readout: Readout: This process results in a significant reduction in bacterial colony-forming units (CFU) and overall biofilm biomass compared to wild-type phages or antibiotics.
The Crisis
Antimicrobial resistance kills 1.27 million people per year. The antibiotic pipeline is dry — 2 new classes in 60 years. Biofilm infections (chronic wounds, cystic fibrosis lungs, prosthetic joints) are essentially untreatable because antibiotics cannot penetrate the extracellular polymeric matrix. We are running out of time.
The Hypothesis
Synthetic biology-engineered bacteriophage cocktails, expressing biofilm-degrading enzymes (dispersin B, DNase I) as late-gene payloads, will achieve >90% biofilm eradication in chronic wound models — outperforming even last-resort antibiotics like colistin — and will be clinically deployable within a decade via DeSci-funded open-source phage libraries.
Mechanism
- Wild-type phages already infect and lyse bacteria, but biofilms protect cells via EPS matrix
- Engineer phages to express dispersin B (degrades poly-N-acetylglucosamine) and DNase I (degrades eDNA scaffold) during late lysis phase
- As each infected bacterium lyses, it releases both new phages AND matrix-degrading enzymes
- This creates an autocatalytic destruction cascade: lysis → enzyme release → biofilm disruption → more bacteria exposed → more infection → more lysis
- Multi-phage cocktails (3-5 phages per target species) prevent resistance emergence
Evidence Basis
- Lu & Collins (2007, PNAS): Engineered T7 phage expressing DspB reduced E. coli biofilms by 99.997%
- Adaptive Phage Therapeutics: compassionate use cases showing phage efficacy against XDR infections
- CRISPR-Cas13 phage payloads have been demonstrated for sequence-specific killing
- Synthetic phage genomes can now be assembled in <2 weeks using cell-free TX-TL
Proposed Test
- Engineer 3 T4-family phages against P. aeruginosa PAO1, each carrying dispersin B + DNase I cassettes
- Test against 72-hour mature biofilms in a CDC biofilm reactor
- Quantify: CFU reduction, biofilm biomass (crystal violet), EPS degradation (confocal)
- Compare vs: wild-type phage cocktail, colistin (4 μg/mL), ciprofloxacin, and combination
- Prediction: Engineered cocktail achieves >4 log CFU reduction; wild-type phages achieve <2 log
Implications
Phages are the original programmable antimicrobial — 10^31 exist on Earth, evolving in real-time against every bacterial species. By adding synthetic payloads, we convert them from narrow-spectrum killers into biofilm-busting platforms. The DeSci angle: phage libraries should be open-source public goods, not locked in pharma IP silos. Sequence a patient's infection, match from the library, manufacture locally. The post-antibiotic era doesn't have to be dark. It can be programmable.
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