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1.
bioRxiv ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39091768

RESUMO

On the flanks of >6000 m Andean volcanoes that tower over the Atacama Desert, leaf-eared mice (Phyllotis vaccarum) live at extreme elevations that surpass known vegetation limits. What the mice eat in these barren, hyperarid environments has been the subject of much speculation. According to the arthropod fallout hypothesis, sustenance is provided by windblown insects that accumulate in snowdrifts ('aolian deposits'). It is also possible that mice feed on saxicolous lichen or forms of cryptic vegetation that have yet to be discovered at such high elevations. We tested hypotheses about the diet of mice living at extreme elevations on Atacama volcanoes by combining metagenomic and DNA metabarcoding analyses of gut contents with stable-isotope analyses of mouse tissues. Genomic analyses of contents of the gastrointestinal tract of a live-captured mouse from the 6739 m summit of Volcán Llullaillaco revealed evidence for an opportunistic but purely herbivorous diet, including lichens. Although we found no evidence of animal DNA in gut contents of the summit mouse, stable isotope data indicate that mice native to elevations at or near vegetation limits (~5100 m) include a larger fraction of animal prey in their diet than mice from lower elevations. Some plant species detected in the gut contents of the summit mouse are known to exist at lower elevations at the base of the volcano and in the surrounding Altiplano, suggesting that such plants may occur at higher elevations beneath the snowpack or in other cryptic microhabitats.

2.
Am Nat ; 203(6): 726-735, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781524

RESUMO

AbstractIn the world's highest mountain ranges, uncertainty about the upper elevational range limits of alpine animals represents a critical knowledge gap regarding the environmental limits of life and presents a problem for detecting range shifts in response to climate change. Here we report results of mountaineering mammal surveys in the Central Andes, which led to the discovery of multiple species of mice living at extreme elevations that far surpass previously assumed range limits for mammals. We livetrapped small mammals from ecologically diverse sites spanning >6,700 m of vertical relief, from the desert coast of northern Chile to the summits of the highest volcanoes in the Andes. We used molecular sequence data and whole-genome sequence data to confirm the identities of species that represent new elevational records and to test hypotheses regarding species limits. These discoveries contribute to a new appreciation of the environmental limits of vertebrate life.


Assuntos
Altitude , Animais , Camundongos/genética , Camundongos/fisiologia , Chile , Filogenia , Distribuição Animal
3.
Proc Natl Acad Sci U S A ; 120(42): e2303964120, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37812707

RESUMO

We present stable hydrogen-isotope analyses of volcanic glass ([Formula: see text]Dg) and radiometric ages (U-Pb zircon, U-Th calcite, AMS14C) from deformed sedimentary deposits in the vicinity of the intermontane Pocitos Basin in the central Puna of the Andean Plateau at about 24.5°S. Our results demonstrate 2-km surface uplift since the middle to late Miocene and protracted shortening that persists until the present day, while other sectors of the Puna show evidence for tectonically neutral and/or extensional settings. These findings are at odds with previous studies suggesting near-modern elevations (4 km) of the Puna Plateau since the late Eocene and formation of the intermontane Miocene Arizaro-Pocitos Basin associated with gravitational foundering of a dense lithosphere. Geophysical and geochemical data support the removal of continental lithosphere beneath the Puna, but the timing and mechanisms by which this removal occurs have remained controversial. We hypothesize that intermontane basin formation in the central Puna is the result of crustal shortening since about 20 Ma, followed by rapid surface uplift, likely related to lithospheric delamination.

4.
J Mammal ; 104(5): 1144-1151, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37800100

RESUMO

We report an elevational record for the Andean sigmodontine Puna Mouse Punomys, which is also the first record of the genus in Chile. The record is based on a mummified specimen that we discovered at an elevation of 5,461 m (17,917 feet) in the caldera of Volcán Acamarachi, Región de Antofagasta, Chile. Results of a morphological assessment suggest that the specimen can be provisionally referred to the species P. lemminus. This new record also extends the known geographic distribution of the genus by 700 km to the south and brings the known Chilean mammal richness to a total of 170 living species and 88 genera. This finding highlights the need for increased survey efforts in more remote, high-elevation regions and demonstrates that there is still much to be learned about the mammal fauna of the Andean Altiplano.


Se reporta un registro altitudinal para el roedor sigmodontino Punomys, el cual corresponde a su vez al primer hallazgo del género para Chile. Este se basa en un espécimen momificado encontrado a una elevación de 5,461 m en la caldera del Volcán Acamarachi, Región de Antofagasta, Chile. Los caracteres morfológicos sugieren que el espécimen puede ser referido provisionalmente a la especie P. lemminus. Este nuevo registro amplía la distribución geográfica conocida del género en 700 km al sur, y eleva la riqueza de mamíferos vivientes chilenos a un nuevo total de 170 especies y 88 géneros. Este hallazgo resalta la necesidad de aumentar los esfuerzos de prospección en las regiones más remotas y de mayor altitud y demuestra que aún queda mucho por aprender sobre el ensamble de los mamíferos del Altiplano andino.

5.
Front Plant Sci ; 14: 1048609, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37180385

RESUMO

Although wetlands contain a disproportionately high amount of earth's total soil carbon, many regions are still poorly mapped and with unquantified carbon stocks. The tropical Andes contain a high concentration of wetlands consisting mostly of wet meadows and peatlands, yet their total organic carbon stocks are poorly quantified, as well as the carbon fraction that wet meadows store compared to peatlands. Therefore, our goal was to quantify how soil carbon stocks vary between wet meadows and peatlands for a previously mapped Andean region, Huascarán National Park, Peru. Our secondary goal was to test a rapid peat sampling protocol to facilitate field sampling in remote areas. We sampled soil to calculate carbon stocks of four wetland types: cushion peat, graminoid peat, cushion wet meadow, and graminoid wet meadow. Soil sampling was conducted by using a stratified randomized sampling scheme. Wet meadows were sampled to the mineral boundary using a gouge auger, and we used a combination of full peat cores and a rapid peat sampling procedure to estimate peat carbon stocks. In the lab, soils were processed for bulk density and carbon content, and total carbon stock of each core was calculated. We sampled 63 wet meadows and 42 peatlands. On a per hectare basis, carbon stocks varied strongly between peatlands (avg. 1092 MgC ha-1) and wet meadows (avg. 30 MgC ha-1). Overall, wetlands in Huascarán National Park contain 24.4 Tg of carbon with peatlands storing 97% of the total wetland carbon and wet meadows accounting for 3% of the wetland carbon in the park. In addition, our results show that rapid peat sampling can be an effective method for sampling carbon stocks in peatlands. These data are important for countries developing land use and climate change policies as well as providing a rapid assessment method for wetland carbon stock monitoring programs.

6.
PeerJ ; 11: e14651, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36650841

RESUMO

The biogeographic region of Argentinean Puna mainly extends at elevations higher than 3,000 m within the Andean Plateau and hosts diverse ecological communities highly adapted to extreme aridity and low temperatures. Soils of Puna are typically poorly evolved and geomorphology is shaped by drainage networks, resulting in highly vegetated endorheic basins and hypersaline basins known as salar or salt flats. Local communities rely on soil fertility for agricultural practices and on pastures for livestock rearing. From this perspective, investigating the scarcely explored microbiological diversity of these soils as indicators of ecosystems functioning might help to predict the fragility of these harsh environments. In this study we collected soil samples from 28 points, following a nested design within three different macro-habitats, i.e., Puna grassland, hypersaline salar and family-run crop fields. Total fungi and arbuscular mycorrhizal fungi (AMF) occurrence were analyzed using eDNA sequencing. In addition, the significance of soil salinity and organic matter content as significant predictors of AMF occurrence, was assessed through Generalized Linear Mixed Modeling. We also investigated whether intensive grazing by cattle and lama in Puna grasslands may reduce the presence of AMF in these highly disturbed soils, driving or not major ecological changes, but no consistent results were found, suggesting that more specific experiments and further investigations may address the question more specifically. Finally, to predict the suitability for AMF in the different macro-habitats, Species Distribution Modeling (SDM) was performed within an environmental coherent area comprising both the phytogeographic regions of Puna and Altoandino. We modeled AMF distribution with a maximum entropy approach, including bioclimatic and edaphic predictors and obtaining maps of environmental suitability for AMF within the predicted areas. To assess the impact of farming on AMF occurrence, we set a new series of models excluding the cultivated Chaupi Rodeo samples. Overall, SDM predicted a lower suitability for AMF in hypersaline salar areas, while grassland habitats and a wider temperature seasonality range appear to be factors significantly related to AMF enrichment, suggesting a main role of seasonal dynamics in shaping AMF communities. The highest abundance of AMF was observed in Vicia faba crop fields, while potato fields yielded a very low AMF occurrence. The models excluding the cultivated Chaupi Rodeo samples highlighted that if these cultivated areas had theoretically remained unmanaged habitats of Puna and Altoandino, then large-scale soil features and local bioclimatic constraints would likely support a lower suitability for AMF. Using SDM we evidenced the influence of bioclimatic, edaphic and anthropic predictors in shaping AMF occurrence and highlighted the relevance of considering human activities to accurately predict AMF distribution.


Assuntos
Micorrizas , Humanos , Animais , Bovinos , Micorrizas/genética , Solo , Ecossistema , Entropia , Agricultura/métodos
7.
Pastoralism ; 12(1): 46, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467430

RESUMO

Vicuñas (Vicugna vicugna) were at risk of extinction due to indiscriminate hunting for their fibre in the mid-twentieth century. The conservation of the species included numerous international and regional legal mechanisms, as well as the will and care of local communities. The vicuña was saved, and now it is classified as "Least concern" by the IUCN Red List of Threatened Species. Sustainable harvest of vicuña fibre is achieved by way of the chaku, capture and live-shearing (an ancient practice, now informed by modern knowledge of biology). Although most communities and cooperatives sell raw fibre, prices are falling. The making of artisanal vicuña garments has been identified as an activity that potentially leads to sustainable development in the Andean Altiplano. This paper analyses a key aspect to achieve this goal, a detailed description of the production (including economic and time costs) involved in weaving a shawl. The manual work has been recognized, with an hourly rate and costs calculated. The first action before starting any intervention was a ceremony, in which the family women infused the fibre with the smoke of a local plant, k'oa (Parastrephia spp.). The rituals and traditions are an important part of livelihoods in the Andes. The steps to creating the finished garment were fibre acquisition, dehairing and cleaning the fibre, spinning, twisting, loom weaving, finishing and fringing. The techniques for spinning and weaving are an essential part of the indigenous cultural heritage; no intervention or suggestion was made in that regard. The final cost of the garment was approximately 3,300 US dollars and half of this cost was the dehairing and cleaning of the fibre.

8.
Neotrop Entomol ; 51(6): 840-859, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36378478

RESUMO

A comparative analysis of high-Andean Pierina was carried out, including a total of 25 species. Based on morphological evidence, with an emphasis on venation and genitalia and molecular data, using three genetic markers, we confirm the recent subjective synonymy of the generic names Tatochila Butler, 1870, Piercolias, Staudinger, 1894, Hypsochila Ureta, 1955, Infraphulia Field, 1958, Pierphulia Field, 1958, and Theochila Field, 1958 with Phulia Herrich-Schäffer, 1867. Two new species are described, namely Phulia stoddardi Pyrcz & Cerdeña n. sp., from the Andes of Central Peru, which occurs at an unusually high altitude of close to 5000 m a.s.l. in dry puna habitat, and Phulia phantasma Lamas, Willmott & Boyer n. sp., from dry montane forests in northern Peru and southern Ecuador. An overview of high-elevation butterflies is presented, with some discussion on adaptations to this environment.


Assuntos
Borboletas , Animais , Ecossistema , Equador , Florestas , Peru
9.
Biology (Basel) ; 11(6)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35741352

RESUMO

The Altiplano-Puna region is a high-altitude plateau in South America characterized by extreme conditions, including the highest UV incidence on Earth. The Laguna Negra is a hypersaline lake located in the Catamarca Province, northwestern Argentina, where stromatolites and other microbialites are found, and where life is mostly restricted to microbial mats. In this study, a particular microbial mat that covers the shore of the lake was explored, to unravel its layer-by-layer vertical structure in response to the environmental stressors therein. Microbial community composition was assessed by high-throughput 16S rRNA gene sequencing and pigment content analyses, complemented with microscopy tools to characterize its spatial arrangement within the mat. The top layer of the mat has a remarkable UV-tolerance feature, characterized by the presence of Deinococcus-Thermus and deinoxanthin, which might reflect a shielding strategy to cope with high UV radiation. Chloroflexi and Deltaproteobacteria were abundant in the second and third underlying layers, respectively. The bottom layer harbors copious Halanaerobiaeota. Subspherical aggregates composed of calcite, extracellular polymeric substances, abundant diatoms, and other microorganisms were observed all along the mat as the main structural component. This detailed study provides insights into the strategies of microbial communities to thrive under high UV radiation and hypersalinity in high-altitude lakes in the Altiplano-Puna region.

10.
Parasitol Res ; 121(6): 1587-1595, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35396964

RESUMO

Free-ranging vicuñas (Vicugna vicugna) are handled in some areas of the Andean high plateau region following an ancestral practice known as chaku, which consists in their transient capture and shearing of their fiber for commercialization. In this study, 807 vicuñas captured during 12 chaku events that took place in 2019 in the province of Jujuy, Argentina, were examined for typical mange skin lesions. Twenty-eight of the examined vicuñas presented alopecia with erythema, exudation, hyperkeratosis, and/or bleeding scarred lesions, mostly in the chest, rear and front legs, and inguinal zone. Most of the cases (82%) appeared in Laguna Cucho at 4900 masl, where 23% of the animals presented these skin reactions. Microscopic evaluation of skin scrapings revealed the presence of a great number of 0.1- to 0.4-mm-long mites of different life cycle stages, morphologically compatible with the species Sarcoptes scabiei. This etiological agent was confirmed by PCR amplification and sequencing of a cox-1 species-specific segment. Histopathological examination of skin biopsies showed extensive infiltration of the dermis with lymphocytes, neutrophils and eosinophils, hyperplasia at different stages, epidermis degeneration, and hyperkeratosis. This is the first characterization of sarcoptic mange in free-ranging vicuñas by clinical examination, mite morphology, histopathological studies, and molecular confirmation in the region. Mange hampers the welfare of vicuñas and the economy of the local communities that organize chaku events since infested vicuñas cannot be sheared. Its long-term effects are unknown but it might affect the fitness and survival of this iconic South American camelid.


Assuntos
Camelídeos Americanos , Escabiose , Animais , Argentina/epidemiologia , Sarcoptes scabiei/genética , Escabiose/diagnóstico , Escabiose/epidemiologia , Escabiose/veterinária , Pele
11.
Front Microbiol ; 13: 791714, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369494

RESUMO

In the Central Andean region in South America, high-altitude ecosystems (3500-6000 masl) are distributed across Argentina, Chile, Bolivia, and Peru, in which poly-extremophilic microbes thrive under extreme environmental conditions. In particular, in the Puna region, total solar irradiation and UV incidence are the highest on Earth, thus, restraining the physiology of individual microorganisms and the composition of microbial communities. UV-resistance of microbial strains thriving in High-Altitude Andean Lakes was demonstrated and their mechanisms were partially characterized by genomic analysis, biochemical and physiological assays. Then, the existence of a network of physiological and molecular mechanisms triggered by ultraviolet light exposure was hypothesized and called "UV-resistome". 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 the genome of Nesterenkonia sp. Act20, an actinobacterium which showed survival to high UV-B doses as well as efficient photorepairing capability. The aim of this work was to use a proteomic approach together with photoproduct measurements to help dissecting the molecular events involved in the adaptive response of a model High-Altitude Andean Lakes (HAAL) extremophilic actinobacterium, Nesterenkonia sp. Act20, under artificial UV-B radiation. Our results demonstrate that UV-B exposure induced over-abundance of a well-defined set of proteins while recovery treatments restored the proteomic profiles present before the UV-challenge. The proteins involved in this complex molecular network were categorized within the UV-resistome subsystems: damage tolerance and oxidative stress response, energy management and metabolic resetting, and DNA damage repair.

12.
Biota Neotrop. (Online, Ed. ingl.) ; 22(2): e20211307, Mar 31, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1374522

RESUMO

Abstract: Among the ecoregions that comprise the high-Andean zone of the Tropical Andes, the Puna and the Yungas stand out for covering a large part of the Peruvian Eastern Andes. Located in the ecotone of these two ecoregions, the Pampa Hermosa National Sanctuary (PHNS) houses one of the priority areas for conservation in Peru. However, the biodiversity of the high-Andean zone of the sanctuary and its surroundings remains poorly studied. Thus, through camera traps and transects, we sought to inventory for the first time the medium and large mammals from the high-Andean region of the PHNS and its buffer zone. We recorded 11 native and three domestic species of medium and large mammals. The richness of native mammals sampled reached 91.7% of the estimated richness (S est.= 11.99 ± 1.85). Among the native species Odocoileus virginianus had the highest relative frequency (56%). We recorded three endemic mammals from the Tropical Andes, Cuniculus taczanowskii, Tremarctos ornatus, and Pudu mephistopheles. The observed richness was higher than most surveys of medium and large mammals carried out in the Puna-forest ecotone in Peru, where the reported richness ranged from 4 to 13 species. In addition, our records of Leopardus pardalis and Eira barbara are the highest for all distribution of these two carnivores. Our results showed that more than 90% of the species recorded were found in it, demonstrating that the entire high-Andean region of the PHNS and its surroundings has an important value for the local mammal community.


Resumo: Dentre as ecorregiões que compreendem a zona alto-andina dos Andes Tropicais, a Puna e as Yungas se destacam por abranger grande parte dos Andes Orientais peruanos. Localizado no ecótono entre estas duas ecorregiões, o Santuário Nacional Pampa Hermosa (SNPH) abriga uma das áreas prioritárias para conservação no Peru. No entanto, a biodiversidade da zona alto-andina do santuário e seu entorno permanece pouco estudada. Dessa forma, através de armadilhas fotográficas e transectos, buscamos inventariar pela primeira vez os mamíferos de médio e grande porte da região alto-andina do SNPH e de sua zona de amortecimento. Nós registramos 11 espécies nativas e três espécies domésticas de mamíferos de médio e grande porte. A riqueza observada dos mamíferos nativos atingiu 91,7% da riqueza estimada (S est.= 11,99 ± 1,85). Dentre as espécies nativas, Odocoileus virginianus foi a que apresentou a maior frequência relativa (56%). Registramos três mamíferos endêmicoss dos Andes Tropicais, Cuniculus taczanowskii, Tremarctos ornatus, e Pudu mephistopheles. A riqueza observada foi superior que a maioria dos levantamentos de mamíferos de médio e grande porte feitos em ecótono Puna-bosque no Peru, onde a riqueza reportada variou de 4 a 13 espécies. Além disso, os registros de Leopardus pardalis e Eira barbara são os mais elevados para toda distribuição destes dois carnívoros. Nossos resultados demonstraram que mais de 90% das espécies registradas foram encontradas nela, demonstrando que toda região alto-andina do SNPH e seu entorno tem um importante valor para a fauna de mamíferos local.

13.
PhytoKeys ; 197: 149-164, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36760673

RESUMO

In an earlier molecular phylogenetic study, a sample of what was originally identified as Cryptanthahispida (Boraginaceae) from Chile, grouped with species of the genus Johnstonella. This sample was subsequently shown not to be C.hispida, but an undescribed species, endemic to the dry Puna of Chile. This new species is described here as Johnstonellapunensis, along with a key to all South American species of the genus. Johnstonellapunensis resembles other members of that genus in having an ovate fruit shape, ovate nutlets and a long style that extends beyond the nutlets. It is unusual in the genus in having a non-tuberculate, dimpled to rugulose nutlet surface sculpturing. Its closest relative within the genus is likely the South American J.diplotricha.


ResumenEn un estudio filogenético molecular anterior, una muestra que originalmente se identificó como Cryptanthahispida (Boraginaceae) de Chile se agrupaba con especies del género Johnstonella. Posteriormente se demostró que esta muestra no era C.hispida sino una especie no descrita, endémica de la Puna seca de Chile. Esta nueva especie se describe aquí como Johnstonellapunensis, junto con una clave para todas las especies sudamericanas del género. Johnstonellapunensis se parece a otros miembros del género por tener un fruto de forma ovadа, clusas ovadas y un estilo largo que sobrepasa las clusas. Es inusual en el género que la clusa tenga una superficie no tuberculada, sino que rugulosa formando hoyuelos. Su pariente más cercano dentro del género es probablemente la especie sudamericana J.diplotricha.

14.
World J Microbiol Biotechnol ; 37(10): 166, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34463818

RESUMO

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.


Assuntos
Actinobacteria/genética , Actinobacteria/isolamento & purificação , Solo/química , Actinobacteria/química , Actinobacteria/classificação , Argentina , Biotecnologia , Ecossistema , Genoma Bacteriano , Genômica , Pressão Osmótica , Microbiologia do Solo
15.
J Fish Biol ; 97(5): 1590-1594, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32888214

RESUMO

This is the first record of the genus Jenynsia in the High Andean Plateau (HAP). It has been found at elevations between 3400 and 3900 m in three endorreheic systems: Salar Antofalla, Antofagasta de la Sierra and El Peñón, northwestern Argentina, South America. This finding increases the number of known HAP fish genera to five. Furthermore, in contrast to the old Andean species-rich genus Orestias, the presence of Jenynsia obscura populations in young high-altitude, non-marine saline wetlands reported here supports a recent dispersal into the HAP.


Assuntos
Distribuição Animal , Ciprinodontiformes/classificação , Ciprinodontiformes/fisiologia , Altitude , Animais , Argentina , Áreas Alagadas
16.
Front Microbiol ; 11: 1343, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655530

RESUMO

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 O2 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.

17.
J Ethnopharmacol ; 251: 112553, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-31923539

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: B. boliviensis and B. tola are used in traditional medicine in the Argentine Puna to treat skin and soft tissue infections and inflammatory processes in humans and animals. AIM OF THE STUDY: To assess the potential of phytotherapeutic preparations of Baccharis species as antifungal agents against clinically relevant fungi and to determine the chemical composition of the extracts. MATERIAL AND METHODS: Phytotherapeutic preparations of B. boliviensis and B. tola collected in Argentine Puna were evaluated as an antifungal agent against clinically relevant fungi (yeast, non-dermatophytes, and dermatophytes) isolated of patients from a local Hospital, and reference strains, using macrodilution and microdilution assays. The bioactivity was supported by UHPLC-OT-MS metabolome fingerprinting. RESULTS: The results revealed that the plant preparations were active against most of evaluated fungal strains; B. boliviensis was more active than B. tola. Dermatophyte fungi strains were the most sensitive isolates. The phytotherapeutic preparation showed Minimal Inhibitory Concentration (MIC) values between 25 and 400 µg GAE/mL and Minimum Fungicidal Concentration (MFC) values between 50 and 400 µg GAE/mL. Regarding the phytochemical analysis, total phenolic and total flavonoid contents of hydroalcoholic preparation of B. boliviensis were greater than those of the B. tola extract. Both Baccharis species showed similar chromatographic patterns, fifty-two compounds were identified based on UHPLC-OT-MS including several terpenoids, flavonoids and phenolic acids that have been identified in this two endemic South American Baccharis species for the first time. Several identified compounds present antifungal properties, the presence of these compounds support the bioactivity of the Baccharis extracts. CONCLUSIONS: In this work the traditional use of both Baccharis species as an antimicrobial against commercial products resistant fungal strains was validate, principally against dermatophytes fungi such as T. rubrum, T. mentagrophytes, M. canis, and M. gypseum. These results indicate that the hydroalcoholic preparations could be used for the treatment of fungal infectious.


Assuntos
Antifúngicos/farmacologia , Baccharis , Fungos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antifúngicos/química , Argentina , Flavonoides/análise , Flavonoides/farmacologia , Testes de Sensibilidade Microbiana , Fenóis/análise , Fenóis/farmacologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química
18.
J Food Sci ; 84(12): 3352-3363, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31782531

RESUMO

Parastrephia lucida (Compositae), Tessaria absinthioides (Compositae), and Ephedra multiflora (Ephedraceae), three plant species from the Argentinean Puna (3600 m.a.s.l.) were selected for their anti-inflammatory and antioxidant properties to prepare mixtures to evaluate their use as nutraceuticals. Seven binary and ternary herbal mixtures made of ethanol 20% extracts of the selected plant species were prepared (Mixtures A to G), and they were analyzed for their effect on proinflammatory enzymes and their antioxidant activity in two cellular systems and in cell free systems. Toxicity tests were also carried out, and they were analyzed by high-performance liquid chromatography with a diode-array detector (HPLC-DAD) to quantify chemical markers. Mix A (equal parts of the three selected plant species) showed an important inhibitory capacity of different proinflammatory enzymes. Its potency on COX-2 was also higher than that of ibuprofen. Mix A and Mix G (P. lucida and T. absinthioides 1:1) showed a high antioxidant capacity in cellular and in cell-free systems. Toxicity assays further demonstrated their safety. This work shows the potential use of herbal mixtures made of medicinal plant species from the Argentinean Puna as nutraceutical or dietary supplements with antioxidant and anti-inflammatory activities. PRACTICAL APPLICATION: P. lucida, T. absinthioides, and E. multiflora are three plant species that are commonly used by Argentinean Puna inhabitants with medicinal purposes. Their proven safety, their antioxidant activity as well as their capacity to inhibit different proinflammatory enzymes make them attractive candidates to be used in combination as part of a dietary supplement aimed to prevent or palliate gastrointestinal and systemic inflammatory diseases. The use of native plant species as an alternative to more common and commercial plant species would have a positive impact on local communities' economies.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Asteraceae/química , Ephedra/química , Extratos Vegetais/farmacologia , Anti-Inflamatórios/análise , Antioxidantes/análise , Argentina , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais/análise , Humanos , Extratos Vegetais/análise , Plantas Medicinais/química
19.
Zootaxa ; 4656(2): zootaxa.4656.2.10, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31716831

RESUMO

Two new species of butterflies of the genus Argyrophorus Blanchard (Nymphalidae, Satyrinae)-A. idealis n. sp. and A. rubrostriata n. sp.-are described from the Cordillera Negra in north-central Peru. Both, as indicated by colour patterns, male and female genitalia, are related to Argyrophorus lamna (Thieme) which occurs further east and southwards. The new species occur in open puna grassland at approximately 4000 m. One of them is exceptional because both fore and hindwings are uniform shining silvery, in this respect similar only to the Chilean A. argenteus Blanchard.


Assuntos
Borboletas , Animais , Chile , Ásia Oriental , Feminino , Masculino , Peru
20.
Environ Monit Assess ; 191(10): 635, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31522254

RESUMO

This study aimed to analyze the spatial and temporal variation of the vegetation in the northern Argentine Puna, utilizing both field sampling and remote-sensing tools. The study was performed within the Pozuelos Biosphere Reserve (Jujuy province, Argentina), which aims to generate socio-economic development compatible with biodiversity conservation. Our study was designed to analyze the dynamics of the Puna vegetation at local scale and assess and monitor the seasonal (dry and wet seasons), interannual, and spatial variation of the vegetation cover, biomass, dominant species, and vegetation indices. Ten vegetation units (with differences in composition, cover, and high and low stratum biomass) were identified at our study site. The diversity of these vegetation units correlated with geomorphology and soil type. In the dry season, the vegetation unit with greatest vegetation cover and biomass was the Festuca chrysophylla grassland, whereas in the wet season, the units with greatest cover and biomass were vegas (peatlands) and short grasslands. The Festuca chrysophylla grasslands and short grasslands were located in areas with clay soils, except peatlands, associated with valleys and coarse-texture soils. The vegetation indices used (NDVI, SAVI, and MSAVI2) were able to differentiate functional types of vegetation and showed a good statistical fit with cover values. Our results suggest that the integrated utilization of remote-sensing tools and field surveys improves the assessment of the Puna vegetation and would allow a periodic monitoring at production unit scale taking into account its spatial and temporal variation.


Assuntos
Monitoramento Ambiental/métodos , Pradaria , Plantas/classificação , Argentina , Biodiversidade , Biomassa , Parques Recreativos , Tecnologia de Sensoriamento Remoto , Estações do Ano , Solo/química
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