Discovering new antibiotics

Just weeks after Prime Minister David Cameron called for a worldwide cut in the unnecessary use of antibiotics and rewards for drug companies which develop new medicines to fight drug-resistant superbugs, the scientists have been studying soil bacteria which, they say, have the genetic potential to “produce tens of thousands of novel antibiotics”.

The South Korean-led study has been supported by University of Brighton scientists Professor Colin Smith and Dr Giselda Bucca in the university’s College of Life, Health and Physical Sciences.

The scientists undertook a detailed study of the activity of genes that are responsible for antibiotic production in a soil bacterium called Streptomyces. These bacteria are the major producers of antibiotics that are used worldwide to treat infections. Their study reveals how the activity of the genes for antibiotic production are controlled in the particular species of bacterium they studied – Streptomyces coelicolor – and this new knowledge, they say “suggests new ways for scientists to increase production of known antibiotics and, perhaps more importantly, to discover new antibiotics”.

Professor Colin Smith

Professor Smith said: “There is a critical need for developing new antibiotics because of the global rise in antibiotic resistance. Soil bacteria such as Streptomyces have the genetic potential to produce tens of thousands of novel antibiotics. However, it can be very difficult to coax them to produce these antibiotics in detectable quantities under laboratory conditions.

“The results from our study suggest how we could manipulate these bacteria to switch on production of antibiotics. This could allow us to ‘awaken’ genetic pathways for antibiotics that are not usually active outside of their natural soil environment. This, in turn, could enable us to study their properties and to scale up their production in the laboratory if they look promising as new antibiotics.”

Professor Smith and Dr Bucca are now embarking on a proof-of-concept study with the global pharmaceutical company GlaxoSmithKline to establish whether the same genetic controls operate in other Streptomyces bacteria. Professor Smith said: “If they do then this will open up new possibilities for increasing production of clinically-important antibiotics.”