Genomic insights into an andean multiresistant soil actinobacterium of biotechnological interest

Abstract

Central-Andean Ecosystems (between 2000 and 6000 m above sea level (masl) are typical arid-to-semiarid environments suffering from the highest total solar and ultraviolet-B radiation on the planet but displaying numerous salt flats and shallow lakes. Andean microbial ecosystems isolated from these environments are of exceptional biodiversity enduring multiple severe conditions. Furthermore, the polyextremophilic nature of the microbes in such ecosystems indicates the potential for biotechnological applications. Within this context, the study undertaken used genome mining, physiological and microscopical characterization to reveal the multiresistant profile of Nesterenkonia sp. Act20, an actinobacterium isolated from the soil surrounding Lake Socompa, Salta, Argentina (3570 masl). Ultravioet-B, desiccation, and copper assays revealed the strain’s exceptional resistance to all these conditions. Act20’s genome presented coding sequences involving resistance to antibiotics, low temperatures, ultraviolet radiation, arsenic, nutrient-limiting conditions, osmotic stress, low atmospheric-oxygen pressure, heavy-metal stress, and toxic fluoride and chlorite. Act20 can also synthesize proteins and natural products such as an insecticide, bacterial cellulose, ectoine, bacterial hemoglobin, and even antibiotics like colicin V and aurachin C. We also found numerous enzymes for animal- and vegetal-biomass degradation and applications in other industrial processes. The resilience of Act20 and its biotechnologic potential were thoroughly demonstrated in this work. Supplementary Information The online version contains supplementary material available at 10.1007/s11274-021-03129-9

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

“…The maximum accumulation of photoproducts was found in cultures of the strain DSM 15474 exposed to the UV treatment (1228 bpm). In accordance with its higher UV-resistance profile ( Portero et al, 2019 ; Alonso-Reyes et al, 2021 ), the strain Act20 accumulated 45% less DNA photoproducts (671 bpm) than the strain DSM 15474 (1228 bpm) under UV-exposure. Similar patterns were also detected under DR and FR treatments, in which the strain Act20 accumulated ca.…”

“…The sequenced genome of Nesterenkonia sp. Act20 has been deposited at DDBJ/ENA/GenBank under the accession JADPQH000000000 ( Alonso-Reyes et al, 2021 ). The functional analysis of the identified proteins was performed using tools from the “KEGG” (Kyoto Encyclopedia of Genes and Genomes) and String databases ( Szklarczyk et al, 2017 ) and exhaustive text mining.…”

“…There is extensive research on these poly-extremophiles focusing on the influence of UV irradiation on the molecular profiles and adaptive strategies of model microorganisms isolated from shallow lakes and soil across different sites in the Argentinean and Chilean Central Andes ( Albarracín et al, 2011 , 2015 , 2016 ). Genomics and ultrastructural and physiological assays identified a number of UV-resistance mechanisms of bacterial and archaeal strains ( Zenoff et al, 2006a , b ; Albarracín et al, 2012 , 2014 , 2016 ; Flores et al, 2009 ; Kurth et al, 2015 ; Rasuk et al, 2017 ; Toneatti et al, 2017 ; Portero et al, 2019 ; Alonso-Reyes et al, 2020 , 2021 ).…”

“…Andean microbes’ high UV-resistance profile points to the existence of a network of physiological and molecular mechanisms triggered by ultraviolet light exposure. We called this the “UV-resistome” ( Kurth et al, 2015 ; Portero et al, 2019 ; Alonso-Reyes et al, 2021 ) and it includes some or all of the following subsystems: (i) UV sensing and effective response regulators, (ii) UV-avoidance and shielding strategies, (iii) damage tolerance and oxidative stress response, (iv) energy management and metabolic resetting, and (v) DNA damage repair. Genes involved in the described UV-resistome were recently described in metagenomes ( Kurth et al, 2017 ; Alonso-Reyes et al, 2020 ; Lamprecht-Grandío et al, 2020 ) as well as in many genomes from strains isolated from High-Altitude Andean Lakes (HAAL) including Acinetobacter sp.…”

“…S17 ( Portero et al, 2019 ) and Nesterenkonia sp. Act20 ( Alonso-Reyes et al, 2021 ). Among all these strains, we selected Nesterenkonia sp.…”