Genomic Variation and Arsenic Tolerance Emerged as Niche Specific Adaptations by Different Exiguobacterium Strains Isolated From the Extreme Salar de Huasco Environment in Chilean – Altiplano

Abstract

Castro-Severyn et al. Genomic Variation of Altiplanic Exiguobacterium activity related to arsenic response and/or tolerance. Therefore, Exiguobacterium strains from SH are adapted to physiologically overcome the contrasting environmental conditions, like the arsenic present in their habitat.

Living to the High Extreme: Unraveling the Composition, Structure, and Functional Insights of Bacterial Communities Thriving in the Arsenic-Rich Salar de Huasco Altiplanic Ecosystem

“…We have described this as a gradient from north to south ( Fig. 1 ) ( 8 ), which is consistent with the widely reported heterogeneity for this area and the potential impact of such an extreme condition over the resident organisms ( 29 ). Previous studies have detected variations in conductivity, organic matter, and dissolved oxygen, even in geographically close areas ( 5 , 6 , 30 – 32 ).…”

“…The SH is located between 68°47′, 68°54′ W and 20°15′, 20°20′ S in the Tarapacá region of northern Chile (Google Earth). (Bottom) Illustration of the SH landscape seen from the H0 site toward the southwest; the signs show some particular characteristics of each site (according to those reported by Castro-Severyn et al [ 8 ]).…”

“…The Salar de Huasco (SH), a high-altitude wetland located in the Chilean Altiplano (20°18′18′′S, 68°50′22′′W, Chile) at 3,800 masl (meters above sea level), is a Ramsar protected site, considered a hot spot for microbial life ( 1 , 2 ). This area is labeled as extreme due to the very particular confluence of physicochemical and environmental conditions, including negative water balance, high daily temperature variations, very arid conditions, high salinity, low atmospheric pressure, high solar radiation, and the presence of arsenic (As), among other stressors ( 3 – 8 ).…”

Comparative genomics of Exiguobacterium reveals what makes a cosmopolitan bacterium

“…The copyright holder for this this version posted November 20, 2020. ; https://doi.org/10.1101/2020. 11.19.390823 doi: bioRxiv preprint psychrophilic and thermophilic adaptations and multiple toxic compound resistances (22)(23)(24). However, comprehensive knowledge about these bacteria evolutionary adaptation to marine and non-marine habitats remains undiscovered.…”

“…Bacteria of the genus Exiguobacterium are Gram-positive facultative anaerobes which have been frequently isolated from various habitats including seawater, marine sediment, marine algae (15–17), soil (17), freshwater (18), plant rhizosphere (19), and some extreme environments such as salt lake (20), glacier and hot spring (21). Genomic analysis of these bacteria has provided some vital insights into their psychrophilic and thermophilic adaptations and multiple toxic compound resistances (22–24). However, comprehensive knowledge about these bacteria evolutionary adaptation to marine and non-marine habitats remains undiscovered.…”