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1.
Biol. Res ; 55: 12-12, 2022. ilus, tab
Article in English | LILACS | ID: biblio-1383915

ABSTRACT

BACKGROUND: The Atacama salt flat is located in northern Chile, at 2300 m above sea level, and has a high concentration of lithium, being one of the main extraction sites in the world. The effect of lithium on microorganism communities inhabiting environments with high concentrations of this metal has been scarcely studied. A few works have studied the microorganisms present in lithium-rich salt flats (Uyuni and Hombre Muerto in Bolivia and Argentina, respectively). Nanocrystals formation through biological mineralization has been described as an alternative for microorganisms living in metal-rich environments to cope with metal ions. However, bacterial lithium biomineralization of lithium nanostructures has not been published to date. In the present work, we studied lithium-rich soils of the Atacama salt flat and reported for the first time the biological synthesis of Li nanoparticles. RESULTS: Bacterial communities were evaluated and a high abundance of Cellulomonas, Arcticibacter, Mucilaginibacter, and Pseudomonas were determined. Three lithium resistant strains corresponding to Pseudomonas rodhesiae, Planomicrobium koreense, and Pseudomonas sp. were isolated (MIC > 700 mM). High levels of S2− were detected in the headspace of P. rodhesiae and Pseudomonas sp. cultures exposed to cysteine. Accordingly, biomineralization of lithium sulfide-containing nanomaterials was determined in P. rodhesiae exposed to lithium salts and cysteine. Transmission electron microscopy (TEM) analysis of ultrathin sections of P. rodhesiae cells biomineralizing lithium revealed the presence of nanometric materials. Lithium sulfide-containing nanomaterials were purified, and their size and shape determined by dynamic light scattering and TEM. Spherical nanoparticles with an average size < 40 nm and a hydro-dynamic size ~ 44.62 nm were determined. CONCLUSIONS: We characterized the bacterial communities inhabiting Li-rich extreme environments and reported for the first time the biomineralization of Li-containing nanomaterials by Li-resistant bacteria. The biosynthesis method described in this report could be used to recover lithium from waste batteries and thus provide a solution to the accumulation of batteries.


Subject(s)
Nanoparticles/chemistry , Lithium/pharmacology , Pseudomonas , Bacteria , Biomineralization
2.
Bol. latinoam. Caribe plantas med. aromát ; 19(3): 300-313, mayo 2020. ilus, tab
Article in English | LILACS | ID: biblio-1116300

ABSTRACT

Every 3 to 7 year angiosperms species of the flowering desert appear in the Atacama Region of Chile, as a result of the climatic phenomenon "El Niño". Our objective was to evaluate the universality of matK and rbcL barcode markers of these species, and validate their taxon through phylogenetic relationships. Argemone hunnemannii, Oenothera coquimbensis, Malesherbia humilis, Leucocoryne appendiculata, Loasa elongata, Nicotiana solanifolia, Stachys grandidentata, Aristolochia chilensis, Alstroemeria kingii and Adesmia eremophila, almost all classified as endemic to Chile, were collected in Pan de Azúcar and Llanos de Challe National Park (Atacama Region, Chile) at the end of October 2017. The phylogeny of these ten angiosperm species from the flowering desert was analyzed using rbcL and matK markers with the maximum likelihood and Bayesian inference methods. The results showed that 70% of the species can be distinguished with the matK or rbcL locus, however, 100% were distinguished using both loci. The phylogenetic results showed that the species formed clades with high reliability and high support with both the matK and rbcL genes, when comparing our results with sequences obtained from GenBank. The matK and rbcL genes are efficient markers for analyzing phylogenetic relationships and validating the taxonomy of flowering species.


Las especies de angiospermas del Desierto Florido de la Región de Atacama de Chile aparecen cada 3 a 7 años, influenciado por el fenómeno climático "El Niño". Nuestro objetivo fue evaluar la universalidad de los marcadores de código de barra matK y rbcL de estas especies, y validar su taxón por medio de relaciones filogenéticas. Las especies Argemone hunnemannii, Oenothera coquimbensis, Malesherbia humilis, Leucocoryne appendiculata, Loasa elongata, Nicotiana solanifolia, Stachys grandidentata, Aristolochia chilensis, Alstroemeria kingii y Adesmia eremophila son clasificadas la mayoría endémicas de Chile. Estas especies fueron colectadas en el Parque Nacional Pan de Azúcar y Llanos de Challe, Región de Atacama, Chile. La colecta se realizó a fines de octubre de 2017. Con los marcadores rbcL y matK se analizó la filogenia con los métodos máxima verosimilitud e inferencia bayesiana en diez especies de angiosperma del Desierto Florido. Los resultados mostraron que el 70% de las especies pueden ser distinguidas con un locus matK o rbcL, sin embargo, el 100% se distinguió usando ambos locus. Los resultados filogenéticos mostraron que las especies formaron clados con alta fiabilidad y alto soporte tanto con los genes matK y rbcL, al comparar con accesos de secuencias obtenidas de GenBank. Lo genes matK y rbcL son marcadores eficientes para analizar relaciones filogenéticas y validar el taxón de las especies de flor.


Subject(s)
Phylogeny , Plants/genetics , Desert , DNA Barcoding, Taxonomic/methods , Ribulose-Bisphosphate Carboxylase , Chile , Sequence Analysis, DNA
3.
Rev. bras. entomol ; 63(2): 104-107, Apr.-June 2019. tab, graf
Article in English | LILACS | ID: biblio-1045560

ABSTRACT

Abstract The sedge-feeding moth Bactra verutana Zeller, 1875 (Lepidoptera: Tortricidae: Olethreutinae: Bactrini), described from Dallas, Texas, USA, is widespread, recorded throughout much North America, Central and South America, including the Caribbean, and Africa. The species is recorded for the first time from Chile based on specimens collected in the coastal valleys of the Atacama Desert, where its larvae feed on Cyperus corymbosus Rottb. var. subnodosus (Nees & Meyen) Kük. (Cyperaceae). A single DNA barcode haplotype, which is widespread in USA, was found in two Chilean specimens sequenced.

4.
Rev. bras. entomol ; 62(3): 243-248, July-Sept. 2018. graf
Article in English | LILACS | ID: biblio-1045515

ABSTRACT

ABSTRACT Glena mielkei Vargas, 2010 (Lepidoptera: Geometridae: Ennominae: Boarmiini) is a Neotropical geometrid moth native to the Atacama Desert of northern Chile whose larvae are folivorous on the shrub Trixis cacalioides (Asteraecae). The last instar and pupa are described and illustrated, and DNA barcode sequences are provided for the first time for G. mielkei. Descriptions are made based on larvae collected in the type locality. Comparisons with the available descriptions of congeneric species suggest that the chaetotaxy of the SV group of the abdominal segment and the morphology of the cremaster could be useful tools to species identification based on last instar and pupa, respectively. A search in BOLD (Barcode of Life Data System) showed that the only DNA barcode haplotype found in the two specimens sequenced was closest to Physocleora Warren, 1897 than Glena Hulst, 1896. These results coincide with the morphological peculiarities of the genitalia highlighted in the original description of G. mielkei, suggesting that a definitive assessment of the generic status of this geometrid moth deserves further integrative studies.

5.
Mem. Inst. Oswaldo Cruz ; 111(3): 209-217, Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-777369

ABSTRACT

Fungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values≤ 125.0 µg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 µg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 µg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity.


Subject(s)
Animals , Antifungal Agents/pharmacology , Aspergillus/chemistry , Desert Climate , DNA, Fungal/isolation & purification , Paracoccidioides/drug effects , Chlorocebus aethiops , Chromatography, Reverse-Phase , Cell Survival/drug effects , Cytochalasins/analysis , Mass Spectrometry , Methylene Chloride , Microbial Sensitivity Tests , Phylogeny , Sequence Analysis, DNA , Solid Phase Extraction , Vero Cells/drug effects
6.
Rev. bras. entomol ; 58(1): 95-97, Jan.-Mar. 2014.
Article in English | LILACS | ID: lil-707156

ABSTRACT

First host plant records for Iridopsis hausmanni Vargas (Lepidoptera, Geometridae) in the coastal valleys of northern Chile. The trees Haplorhus peruviana Engl. and Schinus molle L. (Anacardiaceae) are mentioned as the first host plant records for the little known native moth Iridopsis hausmanni Vargas, 2007 (Lepidoptera, Geometridae, Ennominae) in the coastal valleys of the northern Chilean Atacama Desert. This is also the first record of Anacardiaceae as host plant for a Neotropical species of Iridopsis Warren, 1894.

7.
An. acad. bras. ciênc ; 83(1): 211-219, Mar. 2011. ilus
Article in English | LILACS | ID: lil-578292

ABSTRACT

Partial remains of a titanosaur sauropod collected in the Tolar Formation (Upper Cretaceous) at the Atacama Desert (Antofagasta Region), northern Chile, is described, and a new species, Atacamatitan chilensis gen. et sp. nov., is erected. The material consists mainly of dorsal and caudal vertebrae, part of a humerus and a femur. The presence of a titanosaur confirms the Cretaceous age for the outcrops of red sandstone of the Tolar Formation whose age was previously uncertain, ranging from the Upper Cretaceous to the Paleocene. The new specimen represents the most complete dinosaur reported for this region and one of the most complete titanosaur known from Chile and the pacific margin of South America so far.


Um esqueleto incompleto de um dinossauro titanossaurídeo de depósitos da Formação Tolar (Cretáceo Superior) do deserto do Atacama (região de Antofagasta), norte do Chile é descrito e uma nova espécie, Atacamatitan chilensis gen. et sp. nov., é proposta. O material consiste principalmente de vértebras dorsais e caudais e de partes do úmero e fêmur. A presença de umtitanossauro confirma a idade Cretácea para os afloramentos de arenito avermelhado da Formação Tolar, que eram anteriormente tidos como depositados entre o Cretáceo Superior e o Paleoceno. O exemplar representa o mais completo titanossauro até hoje encontrado na região e um dos mais completos reportados até o momento do Chile e da margem do Oceano Pacífico na América do Sul.


Subject(s)
Animals , Bone and Bones/anatomy & histology , Dinosaurs/anatomy & histology , Dinosaurs/classification , Fossils , Chile , Femur/anatomy & histology , Humerus/anatomy & histology , Spine/anatomy & histology
8.
Interciencia ; 34(5): 338-343, mayo 2009. tab
Article in English | LILACS | ID: lil-630735

ABSTRACT

The model that chronic arsenic (As) exposure causes many teratogenic consequences is tested. Ancient northern Chilean populations appear to be optimal to undertake such a study as these populations are believed to have been largely stationary and ingested significant As levels over time. The Camarones River water, along the Atacama Desert, has extreme As values, 100 times above the norm. We tested the hypothesis that ancient populations, starting with the Chinchorro culture, 5000 years B.C., were significantly affected by this heavy metal and massive arsenic contamination played a role in the origin of Chinchorro artificial mummification practices. We examined 199 skeletons, housed at the Museo Arqueológico San Miguel de Azapa, Universidad de Tarapacá, Arica, Chile, searching for seven teratogenic related pathological conditions: cleft palate, polydactyly, syndactyly, spina bifida, club foot, eye malformations, and hip joint dislocation. Of the seven pathological conditions under assessment, only spina bifida was clearly found in the surveyed sample. Thus, the As teratogenic hypothesis cannot be fully demonstrated. However, the presence of spina bifida in the three valleys suggests a genetic-environmental interplay within the populations. The endemic presence of As in both the Chinchorro mummies and their material culture do strongly support the As hypothesis as a valid explanation for why the Chinchorro first began to anthropogenically mummify their dead.


En este trabajo se evalúa el modelo que la exposición crónica al arsénico (As) juega un rol importante en el desarrollo de anomalías teratógenas. Las poblaciones ancestrales del norte de Chile son adecuadas para ello, ya que por varios milenios han estado expuestas a cantidades importantes del elemento y tienen continuidad biocultural. El agua del río de Camarones, en el Desierto de Atacama, contiene niveles de As muy elevados, 100 veces lo recomendado por normas internacionales, por lo cual se testeó la hipótesis que los primeros habitantes de esta zona, los Chinchorros, estaban afectados por este metal a partir del 5000 A.C. y que el mismo influyó en el origen de complejas prácticas de momificación. Fueron examinados 199 esqueletos del Museo Arqueológico San Miguel de Azapa, Universidad de Tarapacá, Arica, Chile, buscando evidencias de siete patologías supuestamente teratógenas y relacionadas al As: labio leporino, polidactilia, sindactilia, espina bífida, pie equino, deformaciones de los ojos y dislocación de la cadera. Los hallazgos revelan que el impacto del As varía regionalmente y que las poblaciones del valle de Camarones tuvieron mayores frecuencias de lesiones a la piel y espina bífida. Los datos no avalan la hipótesis teratógena, ya que solo se encontró espina bífida en las poblaciones estudiadas. Sin embargo, la presencia de espina bífida en los tres valles muestreados implica una compleja interacción genética y medioambiental. La presencia endémica del As en las momias y en su cultura material refuerza la hipótesis del As para explicar el surgimiento de la compleja momificación artificial en poblaciones Chinchorro.


Neste trabalho foi avaliado o modelo de que a exposição crônica ao arsênico ("As") desempenha um papel importante no desenvolvimento de anomalias teratógenas. As populações ancestrais do norte do Chile são adequadas para isso, já que por vários milênios têm estado expostas a quantidades importantes do elemento e têm continuidade biocultural. A água do rio de Camarones, no Deserto de Atacama, contêm níveis de "As" muito elevados, 100 vezes o recomendado por normas internacionais, pelo qual foi testada a hipótese de que os primeiros habitantes desta zona, os Chinchorros, tinham sido afetados por este metal a partir de 5000 A.C. e que o mesmo influiu na origem de complexas práticas de mumificação. Foram examinados 199 esqueletos do Museu Arqueológico San Miguel de Azapa, Universidade de Tarapacá, Arica, Chile, procurando por evidências de sete patologias supostamente teratógenas e relacionadas ao "As": lábio leporino, polidactilia, sindactilia, espinha bífida, pé equino, deformações dos olhos e deslocamento da cadeira. Os achados revelan que o impacto do "As" varia regionalmente e que as populações do vale de Camarones tiveram maiores frequências de lessões na pele e espinha bífida. Os dados não validam a hipótese teratógena, já que somente achou-se espinha bífida nas populações estudadas. No entanto, a presença de espinha bífida nos três vales amostrados implica uma complexa interação genética e meio-ambiental. A presença endêmica do "As" nas múmias e em sua cultura material reforça a hipótese do "As" para explicar o aparecimento da complexa mumificação artificial em populações Chinchorro.

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