The growing rise in antibiotic resistance has led researchers to look for alternative means for treating infectious diseases.
Researchers at Massachusetts Institute of Technology (MIT) and Harvard have engineered particles called "phagemids" to target and kill specific pathogenic bacteria in a controlled manner.
Researchers modeled the engineered particles on bacteriophages that target specific bacteria while leaving friendly bacteria intact.
Bacteriophages have been used in the past research projects but they can have harmful side effects.
"Bacteriophages kill bacteria by lysing the cell, or causing it to burst. But this is problematic, as it can lead to the release of harmful toxins from the cell and can have harmful side effects," said lead author James Collins, an MIT professor of medical engineering.
The toxins released when the harmful bacteria burst can cause sepsis and even death in some cases.
For the new study, the researchers developed a particle that works in a similar way. It targets and kills specific bacteria, without causing the cells to burst and release their toxins. The particles are called "phagemids" because they infect the target bacteria with plasmids.
They call the particles "phagemids" because they infect the target bacteria with plasmids - small DNA molecules that can copy themselves inside cells.
The team engineered the plasmids using synthetic biology to express proteins and peptides that are toxic to the bacterial host cell. The toxin affects the cells replication and the bacterial cell dies without bursting.
"The method they have developed is highly targeted - it attacks only specific species of bacteria, which means you can use it to treat an infection without harming the rest of the microbiome," said Collins.