New work by researchers at Imperial College London has identified a way to create an effective antibiotic.
Findings from scientists at Imperial College London and the University of Texas may also reveal a potential way to make the antibiotic more powerful.
In the new work, the authors found that colistin literally punches holes in bacteria and makes them burst like balloons.
Colistin (also known as polymyxin E) is an antibiotic produced by some strains of the bacterium Paenibacillus polymyxa. Effective against most gram-negative bacteria.
Colistin was first described in 1947 and is one of the very few antibiotics active against many of the deadliest superbugs, including E. coli, Pseudomonas aeruginosa, and Acinetobacter baumannii, which often infect the lungs of humans.
These superbugs have two shells called membranes. Colistin pierces both membranes, killing bacteria. Colistin has been known to damage the outer membrane by acting on a chemical called lipopolysaccharide (LPS), but how the inner membrane is pierced is unclear.
New work has confirmed that colistin also targets LPS in the inner membrane, although there is very little of it.
During the experiment, the authors used the bacterium Pseudomonas aeruginosa, which also causes serious lung infections in people with cystic fibrosis. They found that a new experimental antibiotic called murepavadin causes LPS to accumulate in the inner skin of bacteria, and then colistin kills bacteria more easily.
If these trials are successful, it may be possible to combine murepavadin with colistin to create a powerful antibiotic for treating a wide range of bacterial infections.