First Report on the Plasmidome From a High-Altitude Lake of the Andean Puna

Abstract

Mobile genetic elements, including plasmids, drive the evolution of prokaryotic genomes through the horizontal transfer of genes allowing genetic exchange between bacteria. Moreover, plasmids carry accessory genes, which encode functions that may offer an advantage to the host. Thus, it is expected that in a certain ecological niche, plasmids are enriched in accessory functions, which are important for their hosts to proliferate in that niche. Puquio de Campo Naranja is a high-altitude lake from the Andean Puna exposed to multiple extreme conditions, including high UV radiation, alkalinity, high concentrations of arsenic, heavy metals, dissolved salts, high thermal amplitude and low O 2 pressure. Microorganisms living in this lake need to develop efficient mechanisms and strategies to cope under these conditions. The aim of this study was to characterize the plasmidome of microbialites from Puquio de Campo Naranja, and identify potential hosts and encoded functions using a deep-sequencing approach. The potential ecological impact of the plasmidome, including plasmids from cultivable and non-cultivable microorganisms, is described for the first time in a lake representing an extreme environment of the Puna. This study showed that the recovered genetic information for the plasmidome was novel in comparison to the metagenome derived from the same environment. The study of the total plasmid population allowed the identification of genetic features typically encoded by plasmids, such as resistance and virulence factors. The resistance genes comprised resistances to heavy metals, antibiotics and stress factors. These results highlight the key role of plasmids for their hosts and impact of extrachromosomal elements to thrive in a certain ecological niche.

A Plasmid Network from the Gut Microbiome of Semi-isolated Human Groups Reveals Unique and Shared Metabolic and Virulence Traits

“…Interestingly, we observed a resistome in the plasmidomes of these human groups that have no or limited exposure to synthetic antibiotics, as well as reported in other isolated or semiisolated groups/locations 7,24,44 . Most of these AR genes are associated with β-lactam and tetracycline resistance, which are commonly seen in soil and water environments 45 .…”

Assessment of the plasmidome of an extremophilic microbial community from the Diamante Lake, Argentina

“…There are myriads of studies addressing bacterial and archaeal plasmids, which eventually revealed the typical functions ensuring plasmid replication, mobilization and maintenance, as well as other accessory characteristics 3 – 12 . Only quite recently, however, it was recognized that to characterize them as a whole is necessary to understand their ecological impact in microbial ecosystems 13 – 18 . In this regard, the total plasmid DNA present in an ecological niche was defined as the “plasmidome” 19 .…”

“…Indeed, plasmidome studies based on independent microbial culture methods substantiated the significance of extrachromosomal genetic elements with respect to different environments, such as the bovine rumen and wastewater treatment plants 13 – 15 . We have recently reported the study of the plasmidome of the Puquio de Campo Naranja, an extreme environment of the Puna Argentina 18 . However, despite the ecological relevance of plasmidomes such studies were only rarely performed, which is possibly due to the complexity of sample processing and the need of tailor-made bioinformatics tools for analysis.…”

“…In this study, we assessed the plasmidome of the red biofilm from Diamante Lake (Fig. 1 D), and compare it to the previously reported plasmidome of microbialites from Puquio de Campo Naranja 18 . In addition, we compared it to the plasmidome from a wastewater-treatment-plant containing effluents of the chemical/pharmaceutical industry (WWTP Visp, Switzerland) as it concerns an environment similarly loaded with high concentrations of metals 15 .…”

Proteomic Signatures of Microbial Adaptation to the Highest UV-Irradiation on Earth: Lessons from a Soil Actinobacterium

“…In the Central Andean region in South America, high-altitude ecosystems (3500-6000 m asl) are distributed across Argentina, Chile, Bolivia and Peru, in which poly-extremophilic microbes thrive under extreme environmental conditions (Albarracín et al, 2009;Albarracín, Gärtner, et al, 2016;Farías, 2020;Orellana et al, 2018;Vignale et al, 2021). Previous works proved the high tolerance profiles of these extremophiles to antibiotics, dryness, heavy-metal, arsenic, hypersalinity, and UV irradiation (Albarracín et al, 2009(Albarracín et al, , 2012Alonso-Reyes, Farias, et al, 2020;Belfiore et al, 2013;Dib et al, 2009;Flores et al, 2009;Kurth et al, 2015Kurth et al, , 2017Omar Federico Ordoñez et al, 2018;Orellana et al, 2018;Perez et al, 2020;Pérez et al, 2017a;Portero et al, 2019;Nicolas Rascovan et al, 2015;Rasuk et al, 2017;Saona et al, 2021;Zannier et al, 2019;. Moreover, various underlying mechanisms and cellular processes were identified that indicate how these indigenous microbes cope with these multiple stress conditions, thus presenting an interesting side-aspect of opening avenues of research for novel biotechnological applications.…”