Researchers from the University of East Anglia and John Innes Centre (JIC) have recently discovered a potential new line of antibiotics that have proven potent against antibiotic resistant ‘superbugs’, Nikita Sall reports.
Consistent and repeated misuse of antibiotics has lead to them becoming increasingly useless, with concerns that bacterial infections developed from minor cuts and scratches could become fatal. It is estimated that antibiotic resistant infections currently kill more than 700,000 people a year, with numbers expected to rise. In addition, there have been no new classes of antibiotics released in the last thirty years as pharmaceutical companies deem them unprofitable. However, the promising discovery of the ability of a certain species of ant to utilise Streptomyces bacteria has given rise to a hopeful beginning of brand-new antibiotics.
Whilst the majority of antibiotics in clinical use come from a group of bacteria called Actinomycetes (traditionally isolated from soil) the idea of screening insects for novel antibiotics is relatively recent. One species of ant, the African fungus-growing plant-ant, Tetraponera penzigi, uses bacteria to defend their nests against invading fungi and microbes. The bacteria isolated from the ants belong to the Streptomyces family and the newly discovered antibiotic they secrete has been named formicamycin – derived from the Latin word for ‘ant’.
Lab tests have shown that these new antibiotics are effective against methicillin resistant Staphylococcus aureus (MRSA) and Vancomycin Resistant enterococci (VRE), which are the most prominent resistant pathogens that cause hospital-acquired infections.
The team isolated several actinomycetes bacterial strains from the ants and using genome-sequencing technologies were able to identify new species with genomes encoding novel antibiotic properties. To test this further, the team repeated the study by growing the strains for 20 generations in low, sub-inhibitory concentrations of formicamycins, and found no sign that the test strain had acquired any level of resistance to the antibiotics.
Research leads at John Innes Centre have opened up saying how their findings highlight how searching under-explored environments, combined with advances in genome sequencing, has enabled the discovery of new species, proving invaluable in the fight against antibacterial resistance.
As this is quite a recent study, with the paper being published this year, human trials have not yet been carried out, with preliminary studies still underway. If all goes to plan, this new line of ‘ant antibiotics’ still won’t be available for another few years.
The innovative idea to screen insects for antibiotics will clearly prove immensely beneficial in the fight against antimicrobial resistance – arguably the greatest medical challenge we all currently face. Many more insect species are yet to be discovered, so there may well be further sources of novel antibiotics we are currently unaware of, with the potential to help us win the battle against pathological bacteria.