Oxygen evolution from extremophilic cyanobacteria confined in hard biocoatings

As water has become a precious resource, there is a growing need for less water-intensive use of microorganisms, while avoiding desiccation stress. Mechanically robust, ready-to-use biocoatings or "living paints" (a type of artificial biofilm consisting of a synthetic matrix containing functional bacteria) represent a novel way to address these issues. Here, we describe the revolutionary, first-ever use of an extremophilic cyanobacterium (Chroococcidiopsis cubana PCC 7433) in biocoatings, which were able to produce high levels of oxygen and carbon capture for at least 1 month despite complete desiccation and subsequent rehydration. Beyond culturing viable bacteria with reduced water resources, this pioneering use of extremophiles in biocoatings could be further developed for a variety of applications, including carbon capture, wastewater treatment and biofuel production.