From Hot Springs to Polar Seas: The Adaptive Potential of Aquatic Biofilms in Extreme Habitats

Abstract

Aquatic biofilms are complex microbial communities that thrive in diverse ecosystems, including some of the most extreme habitats on Earth. From geothermal hot springs and hypersaline lakes to polar seas and deep-sea hydrothermal vents, extremophilic biofilms demonstrate remarkable structural and functional resilience. Their adaptive potential is mediated by unique physiological strategies such as extracellular polymeric substance (EPS) production, stress-responsive gene regulation, and metabolic flexibility. These adaptations not only ensure survival under conditions of high temperature, salinity, pressure, or cold, but also drive ecosystem functions such as nutrient cycling and primary production. Furthermore, extremophilic biofilms hold promising applications in bioremediation, industrial biotechnology, astrobiology, and medical innovation. This article explores the adaptive mechanisms of aquatic biofilms in extreme environments, highlighting their ecological significance and biotechnological potential. Understanding these resilient microbial communities enhances our knowledge of life’s boundaries on Earth and informs the search for extraterrestrial life in analogous extreme habitats.