Bacterial Communities from Extreme Environments: Vulcano Island

Abstract

Although volcanoes represent extreme environments for life, they harbour bacterial communities. Vulcano Island (Aeolian Islands, Sicily) presents an intense fumarolic activity and widespread soil degassing, fed by variable amounts of magmatic gases (dominant at La Fossa Crater) and hydrothermal fluids (dominant at Levante Bay). The aim of this study is to analyse the microbial communities from the different environments of Vulcano Island and to evaluate their possible correlation with the composition of the gas emissions. Microbial analyses were carried out on soils and pioneer plants from both La Fossa Crater and Levante Bay. Total DNA has been extracted from all the samples and sequenced through Illumina MiSeq platform. The analysis of microbiome composition and the gases sampled in the same sites could suggest a possible correlation between the two parameters. We can suggest that the ability of different bacterial genera/species to survive in the same area might be due to the selection of particular genetic traits allowing the survival of these microorganisms. On the other side, the finding that microbial communities inhabiting different sites exhibiting different emission profiles are similar might be explained on the basis of a possible sharing of metabolic abilities related to the gas composition.

Environmental Variables Including Heavy Metals Significantly Shape the Soil Bacterial Community Structure in the Tatun Volcano Group, Northern Taiwan

“…3 ). This was consistent with the findings of previous studies that examined bacterial communities at the phylum level, such as Proteobacteria, Actinobacteria , and Firmicutes ( Singh et al , 2014 ; Fagorzi et al , 2019 ). Several members of these phyla exist in various environments, confirming their capacity to adapt to a wide range of environments.…”

“…Another study provided insights into the spatial distribution of microbial communities at high elevations in a volcanic zone ( Solon et al , 2018 ). A geo-microbiological approach was recently applied to volcanic soils and pioneer plants ( Fagorzi et al , 2019 ).…”

A Proposed Geobiology-Driven Nomenclature for AstrobiologicalIn SituObservations and Sample Analyses

“…Extreme environments that yield high salinity, low a w , and radiation tolerance, among others ( Table 1 ), will have specialized gene expression that tolerates the aforementioned extreme properties. Typically, these ecosystems have a lower microbial diversity than nominal/nonextreme settings due to lower adaptability of microorganisms and tolerant gene expressions that would allow the ongoing maintenance of these biological processes (Summons et al , 2008 ; Msarah et al , 2018 ; Chaya et al , 2019 ; Fagorzi et al , 2019 ; Gugliandolo and Maugeri, 2019 ).…”

Revealing human impact on natural ecosystems through soil bacterial DNA sampled from an archaeological site

“…These changes in the chemical composition at least partially explain the progressive but marked decrease in bacterial diversity as we approached the Roman fort, resulting in the dominance of two taxa in the soils inside the fort. Over‐representation (>75%–85%) of one genus or species in an ecosystem is rare, even in extreme environments (Fagorzi et al, 2019; Frindte et al, 2019) and, to our knowledge, is only found in very specific ecological niches such as grape‐must fermentation, with the spontaneous dominance of the Saccharomyces genus (Guzzon et al, 2022). These unexpected results strongly suggest that the construction of the Roman fort and its human occupancy for four centuries have lastingly modified the soil of this dryland ecosystem, even after 1500 years of human absence.…”