Antibiotics from Scottish Waters
What are antibiotics?
Antibiotics are medicines that are used to prevent and treat bacterial infections. When used correctly, antibiotics save lives.
Bacteria, over time, can become resistant to antibiotics. In fact, antibiotic resistance is a growing global threat for human health, as it can render life-saving drugs ineffective. Many of the antibiotics that have been discovered over the last fifty years can no longer treat the infections they were designed to cure. The term ‘superbugs’ has been used to describe bacteria that are highly drug-resistant. If antibiotic resistance continues to increase, the expected number of deaths due to bacterial infections is predicted to rise to 10 million people per year by 2050.
How are antibiotics discovered?
Antibiotics are either made in a laboratory or produced naturally. In fact, over 70% of antibiotics come from natural sources. One of the most important medicines in antibiotic history, Penicillin, was discovered by the Scottish scientist Alexander Fleming. Penicillin is produced by mold (fungi) and is highly effective at killing certain bacteria. Microscopic organisms such as bacteria, fungi and algae are all producers of antibiotics. In their natural environment, these ‘microorganisms’ have developed the ability to produce chemicals in order to improve their survival. Through taking advantage of this natural chemical warfare between microorganisms, we can discover new antibiotics.
The marine environment: What lies hidden in our oceans?
Research into new antibiotics initially focused on microbes which were found on land; from our deserts to our jungles. However, recent inspection of marine environments has led to the discovery of antibiotics which are of a great interest to today’s scientists. The oceans cover two thirds of Earth's surface and exhibit incredible biological diversity but much of the bacteria remains unstudied. The potential opportunity for the discovery of new drugs is both immeasurable and exciting.
Scotland has around 18,000 Km of coastline, which is approximately six times the size of its land area. The biological richness of the Scottish marine environment is hard to calculate but scientists are attempting to unlock its potential. Somewhere in its depths could be cures for the diseases of today and tomorrow.
Bacteria from the ocean
Bacteria play an important role in marine ecosystems. They interact with many other marine organisms such as sponges, for instance. Although the functions of these interactions are not fully understood, marine bacteria produce chemical compounds, which may offer protection to their host.
Bacteria are responsible for almost half of the antibiotics that are in clinical use, which explains our interest in studying these incredible microorganisms. Marine bacteria are difficult to grow in the laboratory by conventional methods. It is estimated that less than one percent of marine bacteria have been collected for study by scientists. With so much unexplored potential, a pioneering chapter in the history of medical drug discovery awaits the research community.
Algae from the ocean
Marine microalgae are organisms which produce energy in much the same way plants and trees do. There are types of microalgae that have health benefits associated with them. Some are excellent producers of ingredients which boost our immune systems or might act as anti-oxidants. As a result, the substances that they produce are used for nutrition and cosmetics.
Although microalgae produce some useful chemistry, substances like antibiotics are often produced in very small quantities. We must continue our search for the microalgae which produce these interesting and beneficial chemicals.
The Duncan Lab
The Duncan Research Group are based at the University of Strathclyde in Glasgow, Scotland. We use our laboratory to identify new antibiotics.
We do this by separating microorganisms such as bacteria and algae from Scottish marine sediment and water. Once identified, we extract any new chemical compounds so that we may evaluate their antibiotic activity against resistant bacteria. We seek to determine the chemistry that makes these substances so effective so that other scientists might create synthetic drugs that benefit the patients of the future.
To find out more about how the Duncan Lab are searching Scottish waters (and beyond) for biologically active chemistry from marine microorganisms please visit www.medicinesfromthesea.com or www.strath.ac.uk/staff/duncankatherinedr/.
With thanks to Dr Katherine Duncan, Laia Castano Espriu, Alison Hughes and Jonathan Parra Villalobos.