Once underground, experts grew biofilms on native rocks rich in iron and sulfur-bearing minerals. After six months, the team analyzed the microbial composition and physical properties of newly grown biofilms as well as their distributions using microscopy, spectroscopy, and spatial modeling.
The analyzes published in the journal Limits in microbiology, revealed hotspots where the movie was closer. These hotspots correlate with iron-rich mineral grains in the rocks and highlight some mineral preferences for colonizing biofilms.
“Our results demonstrate the strong geographic dependence of biofilm colonization of minerals in rock surfaces,”
According to Casar, these results show that host mineralogy is a key driver for biofilm distribution, which may help improve estimates of the microbial distribution of the Earth’s deep continental subsoil.
“Our findings could inform biofilm’s contribution to global nutrient cycles and also have astrobiological implications, as these findings provide insight into biomass distributions in a Mars analog system,” Casar said.
According to the researcher, extraterrestrial life could exist in underground iron and sulfur-rich environments similar to DeMMO’s rock formations, where the microorganisms are protected from both radiation and extreme temperatures.