This 'spacesuit' for bacteria could keep them and humans alive in space someday

Researchers at the University of California, Berkeley have developed a protective ‘spacesuit’ for bacteria that enables them to survive in harsh environments that would otherwise be lethal to them. These protective suits pair the bacteria with semiconductors that absorb light, lending these organisms the ability to capture carbon dioxide from the environment and turn them into valuable chemicals of use in industry — and perhaps space colonies, too, someday. The researchers created a mesh-like patchwork of molecules with metal atoms in them, called a metal-organic framework (MOF), for the study. This framework restricts the movement of oxygen and its reactive compounds, like peroxide, through them. [caption id=“attachment_5311001” align=“alignnone” width=“1280”] The ‘spacesuit’ wraps itself around the bacteria that expands as the bacteria grows and reproduces. Throughout, it protects them from reactive oxygen, which is one of the primary chemical compounds that spacesuits protect astronauts from. Image courtesy: UCB[/caption] “You can think of the 2D MOF like a sheet of graphene: a one-layer-thick cloak that covers the bacteria,” Omar Yaghi, co-author of the study said to Berkeley’s press. “The 2D MOF is floating in solution with the bacteria, and as the bacteria replicate they are covered further with the 2D MOF layer, so it protects the bacteria from oxygen.” These reactive oxygen species (ROS) are harmful to bacteria and humans alike, and can be lethal to organisms over a range of quantities. This new bacteria-semiconductor ‘hybrid’ can live on carbon dioxide and light, and create different types of compounds depending on the bacteria’s unique metabolic system. The reaction, in essence, is the capture of carbon atoms and building of complex molecules by an agent — in this case, the hybrid bacteria. [caption id=“attachment_5310941” align=“alignnone” width=“1280”] When fed with cadmium (a source of electrons), the bacterium decorates itself with cadmium sulfide particles that absorb light, creating an artificial photosynthesis system — a hybrid — that converts sunlight and carbon dioxide into organic compounds. Image courtesy: UCB[/caption] Not only does this new hybrid offer a change to capture excess carbon dioxide from the ecosystem, it also provides a means of creating useful chemicals in environments like spaceships and other planets where the environment is inhospitable for humans. “Once you fix or activate CO2… and that is the most difficult part… you can use many existing chemical and biological approaches to upgrade them to fuels, pharmaceuticals and commodity chemicals,” said Peidong Yang, lead author from the UC Berkeley’s Department of Chemistry, to university press. The NASA-funded research was pre-published in the journal Proceedings of the National Academy of Sciences.