An article published in the journal “Nature Communications” reports the discovery of a diversity never encountered before in the microorganisms found in one of the hot springs of Yellowstone National Park, in the USA. A team of researchers from Montana State University (MSU) used genomic tools to examine the microbial community in the source called Smoke Jumper 3 (SJ3), discovering both bacteria and Archaea that represent about half of the known branches of these domains of life. It’s an extraordinary discovery because understanding which geological and biological processes can lead to such diversity can provide new information on the reasons why certain life forms can emerge and thrive.
Bacteria and Archaea are two different domains of life. Archaea are unicellular microorganisms with no nucleus that have only really been studied in recent years thanks to advances in genetic analysis techniques. The hot and acid springs of Yellowstone National Park appear to be an ideal environment for microorganisms with exotic metabolisms such as Archaea and in May 2018 an article published in the journal “Nature Microbiology” reported the discovery by other MSU researchers of a new group of Archaea that could be an entire phylum that was called Marsarchaeota.
In this new research, assistant professor Dan Colman, together with associate professor Eric Boyd and student Melody Lindsay, all from MSU, discovered both Archaea and bacteria in the SJ3 source, finding in a small sample a level of biodiversity greater than the combined of all plants and animals within the whole park. The three researchers used genomic tools, based on computer applications to biology to process huge amounts of genetic data, to examine the microorganisms they discovered but also to explain the conditions that allowed that biodiversity to develop and be maintained.
Dan Colman explained that the geographical position of SJ3 is the key to everything, also because it’s on top of one of the largest active volcanoes in the world. In fact, the one in Yellowstone is a supervolcano and its underground activity is constantly monitored because in the event of a supereruption, most of the USA would be devastated and a huge amount of ashes would end up in the atmosphere blocking the sunlight for a time dependent on the duration of the eruption.
SJ3 is fed by significant amounts of volcanic gases generated by boiling hydrothermal water that goes up to the surface. These gases can be mixed with water close to the surface such as rain or snow that melted. The volcanic gases are enriched with hydrogen, methane and carbon monoxide while the waters are rich in oxygen. It’s a mix that improves the conditions that allow the support of microorganisms with the result of having this extraordinary diversity.
The phylogenetic reconstruction of the population of microorganisms was reproduced in the image above (Dan Colman et al. / Nature Communications, C.C. 4.0). The groups, which can reach the phylum level of Archaea (a) and bacteria (b), were reconstructed using a number of genetic markers.
The study of these microorganisms will help to shed light on exotic metabolisms such as those that lead to the generation of methane since a number of that type were discovered. This will help different types of research because it could help to understand the evolution of that type of metabolism but also a more sustainable generation of methane.
