New paper: Antarctic bacterium yields previously unknown iron-scavenging molecules

Antarctica is one of the most extreme environments on Earth. Its cold, dry and nutrient-poor soils harbor microbial communities that have evolved unique survival strategies over millions of years. Because many of these microorganisms remain unexplored, they represent an exciting source of previously unknown natural products with potential applications in medicine and biotechnology.

In a new study, Stanislava Kralova, Alexander Loy, and an interdisciplinary team of scientists investigated a new bacterial species belonging to the genus Actinokineospora, isolated from soils on James Ross Island, Antarctica. Using a combination of genome mining, metabolomics, transcriptomics, and chemical structure analysis, the team discovered an entirely new group of siderophores, which are iron-binding molecules that bacteria produce to capture the scarce iron needed for growth. The researchers named these compounds kineochelins.

The study showed how the bacterium synthesizes a variety of kineochelins and that they bind iron very efficiently. They also inhibit the growth of competing bacteria from the same Antarctic habitat, suggesting that these molecules provide their producer with a competitive advantage in nutrient-poor environments. In addition, kineochelin-enriched fractions displayed activity against opportunistic pathogenic yeasts, highlighting their potential biomedical relevance.

Beyond the discovery of a new class of natural products, the work demonstrates the enormous potential of polar microorganisms for antimicrobial discovery. As antibiotic resistance continues to rise worldwide, studying microbes from underexplored environments such as Antarctica may reveal entirely new chemical compounds that could contribute to the development of future therapeutics and other biotechnological applications.