Diversity of extremophilic bacteria in the sediment of high-altitude lakes located in the mountain desert of Ojos del Salado volcano, Dry-Andes

Abstract

Ojos del Salado, the highest volcano on Earth is surrounded by a special mountain desert with extreme aridity, great daily temperature range, intense solar radiation, and permafrost from 5000 meters above sea level. Several saline lakes and permafrost derived high-altitude lakes can be found in this area, often surrounded by fumaroles and hot springs. The aim of this study was to gain information about the bacterial communities inhabiting the sediment of high-altitude lakes of the Ojos del Salado region located between 3770 and 6500 m. Altogether 11 sediment samples from 4 different altitudes were examined with 16S rRNA gene based denaturing gradient gel electrophoresis and clone libraries. Members of 17 phyla or candidate divisions were detected with the dominance of Proteobacteria, Acidobacteria, Actinobacteria and Bacteroidetes. The bacterial community composition was determined mainly by the altitude of the sampling sites; nevertheless, the extreme aridity and the active volcanism had a strong influence on it. Most of the sequences showed the highest relation to bacterial species or uncultured clones from similar extreme environments.

Microbial community composition in alpine lake sediments from the Hengduan Mountains

“…In this study, Proteobacteria was the dominant phylum in all sediment samples. Many previous studies have shown that the predominance of Proteobacteria in various lake sediment (Aszalós et al, 2016;Dai et al, 2015;Yang et al, 2016). A variety of microorganisms from Proteobacteria participate in various biogeochemical processes in aquatic ecosystems .…”

Shallow ground temperature measurements on the highest volcano on Earth, Mt. Ojos del Salado, Arid Andes, Chile

“…on Mt. Ojos del Salado, although evidence regarding the real volume of ground ice in the region is not available.…”

High altitude, hyper-arid soils of the Central-Andes harbor mega-diverse communities of actinobacteria

“…One such initiative, the multidisciplinary High-Lakes Project, has as a primary objective the assessment of increased environmental stress on the biological disturbance of high altitude lakes during the periods of rapid climate change as an analogy to early Mars (Cabrol et al 2009 ). Other studies have started to chart the diversity and novelty of particular microbial groups (archaea and bacteria, Dorador et al 2010 , 2013 ; Aszalós et al 2016 ; diatoms, Blanco et al 2013 ), to explore polyextremophily (Albarracin et al 2015 ) and diurnal community dynamics in response to solar radiation (Molina et al 2016 ) in these elevated wetland habitats.…”