- Production of metabolic water by bacteria as a strategy for environmental adaptation in alpine and polar environments
Water is the most essential element which directly or indirectly sustains all life forms on Earth. Many animals can only survive for few days in the absence of water. Bacteria, on the other side, can inhabit the driest environments in the planet, such as deserts and glacier ice sheets. In these ecosystems, the presence of liquid water is extremely scarce and water is thus one of the most important limiting factor for biodiversity. Nevertheless, scientists have shown that a wide diversity of bacteria communities can thrive in these extreme ecosystems. But, what adaptation mechanisms allow microbial life in the quasi absence of liquid water?
Bacteria (among other organisms) are capable of producing water as a by-product of their metabolism. This water is known as metabolic water. For years, metabolic water was believed to be of minor quantitative importance as water may potentially freely diffuse through cell membranes. However, recent studies have determined the proportion of metabolic water in the cytoplasm of bacteria by isotope probing. Recent results show that metabolic water can account for 40 to 70% of the water found in the cytoplasm of bacteria in their exponential growth phase. This interesting finding suggests that the production of metabolic water can be much more important for bacteria cells than previously thought.
In this master project, you will contribute to create a collection of bacteria isolates from polar and alpine environments and to quantitatively determine the production of metabolic water in the cultured bacteria under different environmental stressors such as UV radiation, heat and desiccation. The outcomes of this project will allow us to better understand the role of metabolic water production in the adaptation of polar and alpine bacteria to extreme environmental conditions and, secondarily, to determine whether it would be viable to scale-up the production of water in bioreactors so bacteria metabolic water can be used in the future to develop new biotechnological applications, for example as drinking water in space stations or during drought-related emergency situations. Contact us if you are interested!
Contact information: Anna Carratalà ([email protected])