‘Laser-guided chemical warhead’ is a powerful new antibiotic weapon

28 Jun 2018

Image: maradon 333/Shutterstock

To limit the damage of antibiotic resistance, a team of scientists has developed a precision ‘chemical warhead’ that spares the good bacteria and obliterates the bad.

The idea of an ‘antibiotic apocalypse’ is not as science-fiction as it sounds, with healthcare systems and researchers very worried that our overuse of such medication is approaching the point where all antibiotics become useless against even the most common of infections.

With no new antibiotics developed in the past 70 years, new efforts are needed to find ways of making what we have significantly more useful and accurate.

This is why a team of scientists from Boston College in the US has revealed a new breakthrough in targeted antibiotics, effectively creating a precision ‘chemical warhead’ capable of taking out the bad bacteria and leaving the healthy ones unscathed.

With findings published in the Journal of the American Chemical Society, the technology is capable of quickly discovering molecules that potentially recognise any strain of bacteria of interest.

Two major benefits

The concept is based on phage display, a proven strategy used to create and screen peptide libraries containing billions of different composite members displayed on bacteriophage.

While a powerful tool, phage display has been limited to use with the peptides of natural amino acids, but this development expands the ‘chemical space’ of phage display by the incorporation of these so-called chemical warheads, which dramatically enhance a peptide’s potency to bind to biological targets.

By screening this bumper peptide library against live bacteria, the team produced highly selective probes to target two deadly antibiotic-resistant bacterial pathogens: methicillin-resistant Staphylococcus aureus and colistin-resistant Acinetobacter baumannii.

Explaining how it would work, chemist Jianmin Gao said: “First, it can be used to generate imaging agents to confirm a suspected bacterial infection. These probes will go around and look for infected bacteria, find them and attach to them.

“Second, we can attach an antibiotic and the probe will serve to deliver the toxin to only that strain of bacteria.”

The team added that this is just the first step towards the long-term goal of targeted antibiotics, with the hope of using future versions to treat specific strains of deadly and damaging pathogens.

Colm Gorey was a senior journalist with Silicon Republic