Illuminating microbial “dark matter” for antibiotic discovery
The discovery of new antibiotics to combat the rising tide of antibiotic resistant bacteria has been hampered by the rediscovery of commonly encountered antibiotic compounds from soil bacteria. Genomics, however, has shown us that the well of antimicrobials is not yet dry and there are many more potential compounds to find. To do this, however, new approaches are required. Recently, the incubation of different bacteria in co-culture or growth in the presence of sub-inhibitory concentrations of antibiotics has been shown to induce antibiotic production. We are currently investigating induction and co-culturing methodologies across a range of actinomycete bacteria, testing for their ability to inhibit hospital superbugs.
New antibiotics from old bacteria
Development of new antibiotics is key to addressing the crisis in human health caused by the rise of multi-drug resistant superbugs. Empirical screening of bacteria and fungi for bioactive molecules has been the source of the most successful existing antibiotics. The most prolific producers of these metabolites are the Actinobacteria, but high re‑discovery rates amongst soil-derived organisms demand the testing of new reservoirs of biodiversity. Recent studies have shown that human-associated bacteria represent a previously untapped source of antimicrobial diversity and we have begun exploring the antimicrobial activity of a collection of 700 human pathogenic Actinobacteria held by the state microbiology reference laboratory.
Dr Sacha Pidot is a molecular microbiologist and research-teaching academic with interests in identifying and developing new antimicrobials, primarily from Actinomycete bacteria. His PhD piqued his interest in the ways in which bacteria can produce bioactive metabolites, which he followed up with a change in direction to chemical biology under the direction of Professor Christian Hertweck in Germany. Since moving to the Doherty Institute, Sacha has established his own group to continue unearthing new antimicrobials and investigating their biosynthesis.