Arsenic‐tolerant microbial consortia from sediments of Copahue geothermal system with potential applications in bioremediation

Abstract

Although arsenic (As) is recognized as a toxic element for living species, some microorganisms have the ability to tolerate and transform it; recent studies have proposed to take advantage of such capacity to develop sustainable bioremediation strategies. In this study, we evaluated the adaptation to increasing concentrations of As(III) and As(V) of three metabolically different microbial cultures (heterotrophic, autotrophic–acidophilic, and anaerobic) obtained from a sample with low‐soluble As content from the Copahue geothermal system. At the end of the adaptation process, the heterotrophic culture was able to grow at 20 mM and 450 mM of As(III) and As(V), respectively; the autotrophic–acidophilic culture showed tolerance to 15 mM of As(III) and 150 mM of As(V), whereas the anaerobic culture only developed in As(V) at concentrations up to 50 mM. The most tolerant consortia were characterized by their growth performance, complexity, and the presence of genes related to As metabolism and resistance. Regarding the consortia complexity, the predominant genera identified were: Paenibacillus in both heterotrophic consortia, Acidithiobacillus in the autotrophic–acidophilic consortium tolerant to As(III), Acidiphilium in the autotrophic–acidophilic consortium tolerant to As(V), and Thiomonas and Clostridium in the anaerobic consortium. This study is the first report of As tolerance microorganisms obtained from Copahue and reasserts the versatility and flexibility of the community of this natural extreme environment; also, it opens the door to the study of possible uses of these consortia in the design of biotechnological processes where the As concentration may fluctuate.

Complete genome sequence of plant growth‐promoting and heavy metal‐tolerant Enterobacter tabaci 4M9 (CCB‐MBL 5004)

“…So, the presence of the arsC gene in 4M9 may be an indication of its ability to reduce or transform AsV to AsIII. While arsenic is a recognized toxic element in living organisms, it can be tolerated and transformed by some microorganisms [36].…”

Meta-Analysis of Microbial Communities in Hot Springs: Recurrent Taxa and Complex Shaping Factors beyond pH and Temperature

“…In this study, we surveyed the microbial community of three hot springs from two volcanic areas in Neuquén, Argentina. The Caviahue-Copahue region has been extensively studied by this research group [ 28 , 29 , 30 , 31 , 48 , 49 ] and many others [ 50 , 51 , 52 , 53 , 54 ]; on the other hand, Domuyo has been scarcely visited and there is only one report related to hydrolytic enzymes in thermophilic bacteria isolated from this site [ 34 ]. The hot springs sampled were chosen due to their differential conditions of pH and temperature: AL and B9 were acidic ponds, but with different temperatures (71 °C and 57 °C, respectively), while LT was a circumneutral pond with high temperatures (75 °C).…”

A Deeper Look into the Biodiversity of the Extremely Acidic Copahue volcano-Río Agrio System in Neuquén, Argentina

“…Such differences could be explained considering the higher pH, lower Eh, and the iron concentration at this site. Despite the low abundance of the most common acidophiles in this community, species related to Acidithiobacillus, Acidiphilium, and Leptospirillum have been cultured from samples collected from Salto del Agrio [33,43].…”