Presentation #1246 in the session “Open Engagement Session C”.
Geothermal fields harbor environments with conditions resembling primitive Earth and have been proposed as sites where the first life forms might have emerged. Mexico contains many thermal areas as it is crossed from west to east by the Trans-Mexican Volcanic Belt. In particular, the geothermal field of Los Azufres is located in Western Mexico and contains several hot springs, fumaroles, acid lakes, and solfatara fields with unique microbial ecosystems. We propose that the geothermal field of Los Azufres as a good analog for the development of methodologies for the search of past or present life in other places from the solar system and beyond. Our microbiomic studies of thermal sites within Los Azufres have allowed the finding of microorganisms belonging to all domains of life as well as viruses. By sequencing and analyzing metagenomes we were able to recover metagenome assembled genomes for Sulfolobales, Thermoplasmatales, and Micrarchaeota populations, including ‘Candidatus Aramenus sulfurataquae’, ‘Candidatus Cuniculiplasma sp. AZ01’, and ‘Candidatus Micrarchaeum sp. AZ1’. Also, genome sequences were obtained for archaeal viruses that allowed the definition of their core genes. In addition, we were able to detect Proteobacteria, Actinobacteria, Firmicutes, and Nitrospirae as dominant bacterial phyla in several hot springs. In particular, the genome of Acidocella sp. MX-AZ02 was obtained from and acid lake with high levels of heavy metals, and the genomes of Acidibrevibacterium and Aciditerrimonas populations were recovered from fumaroles. Finally microalgal populations related to green and red algae have been detected by metagenomic sequencing Genomic analyses allowed the study of the genetic potential of these microorganisms and we propose that they play a relevant role in biochemical cycles at Los Azufres. Functional studies revealed adaptations for stress response, such as: heat shock, oxidative stress, osmotic shock, and heavy metal resistance. In consequence, we consider that the microbial and viral communities found at Los Azufres may help us better understand the origin of life on Earth, provide clues about the interactions between organisms, and describe the radiation of different ways to obtain energy and resources for life. Besides, data related with our research could provide the first steps toward developing biosignatures and building models for exploring similar environments in other worlds, e.g the ancient fumaroles recently found on Mars, and similar environments in Jovian satellites or exoplanets.