Desert-Dwelling Bacteria Used in Oxygen-Producing Biocoating Could Be Key to Making Mars Habitable

The aerospace industry has entered a new era of space exploration with Mars on the agenda. Central space agencies such as NASA, ESA, Roscosmos, and JAXA have announced plans for future manned missions on the red planet. Such missions, however, face the challenge of creating a breathable environment by converting CO2 from the Martian atmosphere into oxygen gas.

In a recent breakthrough, scientists utilized the oxygen-producing ability of a bacteria called Chroococcidiopsis cubana in creating an innovative paint that could supplement the air on Mars.

An Extraordinary Cyanobacteria

Chroococcidiopsis Cubana is a terrestrial cyanobacteria type with potentially interesting biosynthesis genes. It is known for its ability to live in places on Earth where life is impossible. They can also grow quickly and can be genetically modified in most cases.

Chroococcidiopsis cubana harnesses an extraordinary kind of photosynthesis that can make the most of extremely low-light conditions, even possessing a backup survival mechanism for darker places. It can be found thriving in areas with pitch blackness, such as ultra-deep caves, and in the Earth's lower crust beneath the ocean floor. This cyanobacteria species can also live in deserts, resembling Mars's environment.

Like other cyanobacteria, its metabolism has some desirable characteristics. It takes in CO2 and fixes it to be transformed into organic compounds. It can do so with high efficiency in adverse environments, releasing oxygen.

Green Living Paint

At the University of Surrey, experts developed an innovative paint that can emit measurable amounts of oxygen while reducing CO2 in the air around it. Microbiologist Simone Krings led the research team to create a biocoating named 'Green Living Paint,' which encases live Chroococcidiopsis cubana within layers.

Our planet faces increasing greenhouse gases in the atmosphere and water shortages due to rising global temperatures. According to University of Surrey senior lecturer Dr. Suzie Hingley-Wilson, there is a need for innovative, environmentally friendly solutions using sustainable resources. Mechanically robust biocoatings can meet these challenges since they reduce water consumption in typically water-intensive bioreactor-based processes.

To test the suitability of Chroococcidiopsis cubana as a biocoating, the scientists immobilized the bacteria in a mechanically robust biocoating made from polymer particles in water, drying it fully before rehydrating. It was observed that this bacteria within the biocoating can produce up to 0.4 g of oxygen per gram of biomass per day while capturing CO2. Continuous measurements of oxygen showed that there is no sign of decreasing bacterial activity over a month.

Similar experiments were conducted by researchers with Synechocystis sp., a type of cyanobacteria typically found in freshwater. Unlike its desert counterpart, this bacteria could not produce oxygen within the biocoating.

The results of this study have implications not just for Earth but also for space travel. According to Krings, Chroococcidiopsis cubana can survive in extreme environments such as droughts and after high levels of UV radiation exposure. This extraordinary ability makes them potential candidates for Mars colonization.