The frigid waters of the Arctic Ocean may hold the key to unlocking a new generation of antibiotics. Scientists have discovered that substances produced by Arctic Ocean microbes, specifically actinobacteria, have the potential to inhibit the growth of harmful bacteria and prevent them from causing disease. This discovery is particularly significant as bacteria are becoming increasingly resistant to existing antibiotics, making the search for new drugs a pressing global concern.
Around 70% of currently available antibiotics were derived from actinobacteria, which predominantly reside in terrestrial soil. However, scientists are now looking to the ocean depths, where actinobacteria are thought to produce a greater diversity of chemical compounds due to the extreme environmental conditions they face. These conditions, characterized by fluctuating pressure, temperature, salt concentrations, and light levels, have likely driven the evolution of unique defense mechanisms in marine actinobacteria.
In a recent study, researchers analyzed hundreds of previously unknown compounds extracted from actinobacteria living within invertebrates collected during an Arctic Ocean expedition in 2020. Their focus was on determining the effects of these compounds on a pathogenic strain of E. coli known as enteropathogenic E. coli (EPEC). EPEC bacteria are known to infect intestinal cells, causing severe diarrhea, particularly in children.
The scientists identified two compounds with particularly potent antibacterial properties: one from a strain of actinobacteria belonging to the Rhodococcus genus and another from a strain in the Kocuria genus. These compounds were found to prevent EPEC bacteria from attaching to cell surfaces and injecting substances that hijack the host’s molecular machinery, thereby causing disease.
While the compound produced by the Kocuria bacteria slowed the growth of EPEC bacteria, the compound from Rhodococcus bacteria did not. This is a promising finding, as it suggests that the Rhodococcus compound may be more effective in preventing the development of antibiotic resistance. If the bacteria are alive but rendered harmless to the host, there is less evolutionary pressure for them to develop resistance to the compound.
Despite the exciting potential of these findings, much research remains to be done before either compound can be brought to market. Extensive studies are needed to determine how to produce larger quantities of these compounds for further investigation of their structures and biological activity.
However, the research team is optimistic about the future of this research. They believe that many more promising compounds are waiting to be discovered in the depths of the Arctic Ocean and other marine environments. This discovery highlights the immense potential of marine biodiversity for providing new solutions to pressing global challenges, including the fight against antibiotic resistance.
