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1.
Appl Environ Microbiol ; 90(9): e0059924, 2024 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-39133000

RESUMEN

Leptothrix ochracea creates distinctive iron-mineralized mats that carpet streams and wetlands. Easily recognized by its iron-mineralized sheaths, L. ochracea was one of the first microorganisms described in the 1800s. Yet it has never been isolated and does not have a complete genome sequence available, so key questions about its physiology remain unresolved. It is debated whether iron oxidation can be used for energy or growth and if L. ochracea is an autotroph, heterotroph, or mixotroph. To address these issues, we sampled L. ochracea-rich mats from three of its typical environments (a stream, wetlands, and a drainage channel) and reconstructed nine high-quality genomes of L. ochracea from metagenomes. These genomes contain iron oxidase genes cyc2 and mtoA, showing that L. ochracea has the potential to conserve energy from iron oxidation. Sox genes confer potential to oxidize sulfur for energy. There are genes for both carbon fixation (RuBisCO) and utilization of sugars and organic acids (acetate, lactate, and formate). In silico stoichiometric metabolic models further demonstrated the potential for growth using sugars and organic acids. Metatranscriptomes showed a high expression of genes for iron oxidation; aerobic respiration; and utilization of lactate, acetate, and sugars, as well as RuBisCO, supporting mixotrophic growth in the environment. In summary, our results suggest that L. ochracea has substantial metabolic flexibility. It is adapted to iron-rich, organic carbon-containing wetland niches, where it can thrive as a mixotrophic iron oxidizer by utilizing both iron oxidation and organics for energy generation and both inorganic and organic carbon for cell and sheath production. IMPORTANCE: Winogradsky's observations of L. ochracea led him to propose autotrophic iron oxidation as a new microbial metabolism, following his work on autotrophic sulfur-oxidizers. While much culture-based research has ensued, isolation proved elusive, so most work on L. ochracea has been based in the environment and in microcosms. Meanwhile, the autotrophic Gallionella became the model for freshwater microbial iron oxidation, while heterotrophic and mixotrophic iron oxidation is not well-studied. Ecological studies have shown that Leptothrix overtakes Gallionella when dissolved organic carbon content increases, demonstrating distinct niches. This study presents the first near-complete genomes of L. ochracea, which share some features with autotrophic iron oxidizers, while also incorporating heterotrophic metabolisms. These genome, metabolic modeling, and transcriptome results give us a detailed metabolic picture of how the organism may combine lithoautotrophy with organoheterotrophy to promote Fe oxidation and C cycling and drive many biogeochemical processes resulting from microbial growth and iron oxyhydroxide formation in wetlands.


Asunto(s)
Carbono , Genoma Bacteriano , Leptothrix , Carbono/metabolismo , Leptothrix/metabolismo , Leptothrix/genética , Leptothrix/crecimiento & desarrollo , Humedales , Compuestos Ferrosos/metabolismo , Oxidación-Reducción , Hierro/metabolismo , Ciclo del Carbono , Procesos Autotróficos , Metagenoma
2.
Appl Environ Microbiol ; 90(2): e0204123, 2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38193671

RESUMEN

Zetaproteobacteria have been reported in different marine and terrestrial environments all over the globe. They play an essential role in marine iron-rich microbial mats, as one of their autotrophic primary producers, oxidizing Fe(II) and producing Fe-oxyhydroxides with different morphologies. Here, we study and compare the Zetaproteobacterial communities of iron-rich microbial mats from six different sites of the Lucky Strike Hydrothermal Field through the use of the Zetaproteobacterial operational taxonomic unit (ZetaOTU) classification. We report for the first time the Zetaproteobacterial core microbiome of these iron-rich microbial mats, which is composed of four ZetaOTUs that are cosmopolitan and essential for the development of the mats. The study of the presence and abundance of different ZetaOTUs among sites reveals two clusters, which are related to the lithology and permeability of the substratum on which they develop. The Zetaproteobacterial communities of cluster 1 are characteristic of poorly permeable substrata, with little evidence of diffuse venting, while those of cluster 2 develop on hydrothermal slabs or deposits that allow the percolation and outflow of diffuse hydrothermal fluids. In addition, two NewZetaOTUs 1 and 2 were identified, which could be characteristic of anthropic iron and unsedimented basalt, respectively. We also report significant correlations between the abundance of certain ZetaOTUs and that of iron oxide morphologies, indicating that their formation could be taxonomically and/or environmentally driven. We identified a new morphology of Fe(III)-oxyhydroxides that we named "corals." Overall, our work contributes to the knowledge of the biogeography of this bacterial class by providing additional data from the Atlantic Ocean, a lesser-studied ocean in terms of Zetaproteobacterial diversity.IMPORTANCEUp until now, Zetaproteobacterial diversity studies have revealed possible links between Zetaproteobacteria taxa, habitats, and niches. Here, we report for the first time the Zetaproteobacterial core microbiome of iron-rich mats from the Lucky Strike Hydrothermal Field (LSHF), as well as two new Zetaproteobacterial operational taxonomic units (NewZetaOTUs) that could be substratum specific. We highlight that the substratum on which iron-rich microbial mats develop, especially because of its permeability to diffuse hydrothermal venting, has an influence on their Zetaproteobacterial communities. Moreover, our work adds to the knowledge of the biogeography of this bacterial class by providing additional data from the hydrothermal vent sites along the Mid-Atlantic Ridge. In addition to the already described iron oxide morphologies, we identify in our iron-rich mats a new morphology that we named corals. Finally, we argue for significant correlations between the relative abundance of certain ZetaOTUs and that of iron oxide morphologies, contributing to the understanding of the drivers of iron oxide production in iron-oxidizing bacteria.


Asunto(s)
Respiraderos Hidrotermales , Microbiota , Compuestos Férricos , Hierro/análisis , Azores , Bacterias/genética , Proteobacteria , Respiraderos Hidrotermales/microbiología
3.
Microb Ecol ; 87(1): 80, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829422

RESUMEN

The Gypsum Karst of Sorbas, Almeria, southeast Spain, includes a few caves whose entrances are open and allow the entry and roosting of numerous bats. Caves are characterized by their diversity of gypsum speleothems, such as stalactites, coralloids, gypsum crusts, etc. Colored biofilms can be observed on the walls of most caves, among which the Covadura and C3 caves were studied. The objective was to determine the influence that bat mycobiomes may have on the fungal communities of biofilms. The results indicate that the fungi retrieved from white and yellow biofilms in Covadura Cave (Ascomycota, Mortierellomycota, Basidiomycota) showed a wide diversity, depending on their location, and were highly influenced by the bat population, the guano and the arthropods that thrive in the guano, while C3 Cave was more strongly influenced by soil- and arthropod-related fungi (Ascomycota, Mortierellomycota), due to the absence of roosting bats.


Asunto(s)
Artrópodos , Biopelículas , Sulfato de Calcio , Cuevas , Quirópteros , Hongos , Cuevas/microbiología , Quirópteros/microbiología , Quirópteros/fisiología , Animales , Hongos/clasificación , Hongos/fisiología , Hongos/genética , Hongos/aislamiento & purificación , Artrópodos/microbiología , España , Biodiversidad , Micobioma , Microbiología del Suelo
4.
Environ Sci Technol ; 58(26): 11400-11410, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38889135

RESUMEN

Phosphorus (P) limitation often constrains biological processes in Arctic tundra ecosystems. Although adsorption to soil minerals may limit P bioavailability and export from soils into aquatic systems, the contribution of mineral phases to P retention in Arctic tundra is poorly understood. Our objective was to use X-ray absorption spectroscopy to characterize P speciation and associations with soil minerals along hillslope toposequences and in undisturbed and disturbed low-lying wet sedge tundra on the North Slope, AK. Biogenic mats comprised of short-range ordered iron (Fe) oxyhydroxides were prevalent in undisturbed wet sedge meadows. Upland soils and pond sediments impacted by gravel mining or thermokarst lacked biogenic Fe mats and were comparatively iron poor. Phosphorus was primarily contained in organic compounds in hillslope soils but associated with Fe(III) oxyhydroxides in undisturbed wet sedge meadows and calcium (Ca) in disturbed pond sediments. We infer that phosphate mobilized through organic decomposition binds to Fe(III) oxyhydroxides in wet sedge, but these associations are disrupted by physical disturbance that removes Fe mats. Increasing disturbances of the Arctic tundra may continue to alter the mineralogical composition of soils at terrestrial-aquatic interfaces and binding mechanisms that could inhibit or promote transport of bioavailable P from soils to aquatic ecosystems.


Asunto(s)
Hierro , Fósforo , Tundra , Fósforo/química , Regiones Árticas , Hierro/química , Ecosistema , Espectroscopía de Absorción de Rayos X , Suelo/química , Sedimentos Geológicos/química
5.
J Phycol ; 60(2): 254-272, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38467467

RESUMEN

Benthic cyanobacterial mats are increasing in abundance worldwide with the potential to degrade ecosystem structure and function. Understanding mat community dynamics is thus critical for predicting mat growth and proliferation and for mitigating any associated negative effects. Carbon, nitrogen, and sulfur cycling are the predominant forms of nutrient cycling discussed within the literature, while metabolic cooperation and viral interactions are understudied. Although many forms of nutrient cycling in mats have been assessed, the links between niche dynamics, microbial interactions, and nutrient cycling are not well described. Here, we present an updated review on how nutrient cycling and microbial community interactions in mats are structured by resource partitioning via spatial and temporal heterogeneity and succession. We assess community interactions and nutrient cycling at both intramat and metacommunity scales. Additionally, we present ideas and recommendations for research in this area, highlighting top-down control, boundary layers, and metabolic cooperation as important future directions.


Asunto(s)
Cianobacterias , Ecosistema , Cianobacterias/metabolismo , Azufre/metabolismo , Carbono/metabolismo
6.
J Nanobiotechnology ; 22(1): 211, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678271

RESUMEN

The development of innovative wound dressing materials is crucial for effective wound care. It's an active area of research driven by a better understanding of chronic wound pathogenesis. Addressing wound care properly is a clinical challenge, but there is a growing demand for advancements in this field. The synergy of medicinal plants and nanotechnology offers a promising approach to expedite the healing process for both acute and chronic wounds by facilitating the appropriate progression through various healing phases. Metal nanoparticles play an increasingly pivotal role in promoting efficient wound healing and preventing secondary bacterial infections. Their small size and high surface area facilitate enhanced biological interaction and penetration at the wound site. Specifically designed for topical drug delivery, these nanoparticles enable the sustained release of therapeutic molecules, such as growth factors and antibiotics. This targeted approach ensures optimal cell-to-cell interactions, proliferation, and vascularization, fostering effective and controlled wound healing. Nanoscale scaffolds have significant attention due to their attractive properties, including delivery capacity, high porosity and high surface area. They mimic the Extracellular matrix (ECM) and hence biocompatible. In response to the alarming rise of antibiotic-resistant, biohybrid nanofibrous wound dressings are gradually replacing conventional antibiotic delivery systems. This emerging class of wound dressings comprises biopolymeric nanofibers with inherent antibacterial properties, nature-derived compounds, and biofunctional agents. Nanotechnology, diminutive nanomaterials, nanoscaffolds, nanofibers, and biomaterials are harnessed for targeted drug delivery aimed at wound healing. This review article discusses the effects of nanofibrous scaffolds loaded with nanoparticles on wound healing, including biological (in vivo and in vitro) and mechanical outcomes.


Asunto(s)
Antibacterianos , Vendajes , Nanofibras , Polímeros , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Nanofibras/química , Humanos , Animales , Antibacterianos/farmacología , Antibacterianos/química , Polímeros/química , Sistemas de Liberación de Medicamentos/métodos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Nanopartículas del Metal/química
7.
Int J Phytoremediation ; 26(2): 228-240, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37431240

RESUMEN

Two extremophilic cyanobacterial-bacterial consortiums naturally grow in extreme habitats of high temperature and hypersaline were used to remediate hexavalent chromium and molybdenum ions. Extremophilic cyanobacterial-bacterial biomasses were collected from Zeiton and Aghormi Lakes in the Western Desert, Egypt, and were applied as novel and promising natural adsorbents for hexavalent chromium and molybdenum. Some physical characterizations of biosorbent surfaces were described using scanning electron microscope, energy-dispersive X-ray spectroscopy, Fourier transformation infrared spectroscopy, and surface area measure. The maximum removal efficiencies of both biosorbents were 15.62-22.72 mg/g for Cr(VI) and 42.15-46.29 mg/g for Mo(VI) at optimum conditions of pH 5, adsorbent biomass of 2.5-3.0 g/L, and 150 min contact time. Langmuir and Freundlich adsorption models were better fit for Cr(VI), whereas Langmuir model was better fit than the Freundlich model for Mo(VI) biosorption. The kinetic results revealed that the adsorption reaction obeyed the pseudo-second-order model confirming a chemisorption interaction between microbial films and the adsorbed metals. Zeiton biomass exhibited a relatively higher affinity for removing Cr(VI) than Aghormi biomass but a lower affinity for Mo(VI) removal. The results showed that these extremophiles are novel and promising candidates for toxic metal remediation.


Even though many researchers worked on the field of metal bioremediation, most use single organism or extracted biogenic materials for heavy metals removal. The novelty of this study is the application of a consortium of cyanobacteria and bacteria from extreme habitats (hyper-salinity, high temperature, harsh weather conditions, high intensity of light and UV light) in the field of environmental safety. This specialized microbial film composed of a diverse group of adapted organisms that co-operate between each other making them more effective bio-remediating agent. This study examined the effectiveness of these consortia as metals bioremediator and cover the gap of research results from the scarce application of novel, cheap and eco-friendly extremophiles in toxic metals removal.


Asunto(s)
Cianobacterias , Extremófilos , Contaminantes Químicos del Agua , Molibdeno , Cinética , Biodegradación Ambiental , Cromo/química , Adsorción , Iones , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/análisis
8.
Int J Mol Sci ; 25(3)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38338946

RESUMEN

Poly(vinyl alcohol) is one of the most attractive polymers with a wide range of uses because of its water solubility, biocompatibility, low toxicity, good mechanical properties, and relatively low cost. This review article focuses on recent advances in poly(vinyl alcohol) electrospinning and summarizes parameters of the process (voltage, distance, flow rate, and collector), solution (molecular weight and concentration), and ambient (humidity and temperature) in order to comprehend the influence on the structural, mechanical, and chemical properties of poly(vinyl alcohol)-based electrospun matrices. The importance of poly(vinyl alcohol) electrospinning in biomedical applications is emphasized by exploring a literature review on biomedical applications including wound dressings, drug delivery, tissue engineering, and biosensors. The study also highlights a new promising area of particles formation through the electrospraying of poly(vinyl alcohol). The limitations and advantages of working with different poly(vinyl alcohol) matrices are reviewed, and some recommendations for the future are made to advance this field of study.


Asunto(s)
Nanofibras , Nanofibras/química , Alcohol Polivinílico/química , Polímeros , Ingeniería de Tejidos , Solubilidad
9.
Environ Monit Assess ; 196(4): 408, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38561517

RESUMEN

Cyanobacteria inhabiting lotic environments have been poorly studied and characterized in Mexico, despite their potential risks from cyanotoxin production. This article aims to fill this knowledge gap by assessing the importance of benthic cyanobacteria as potential cyanotoxin producers in central Mexican rivers through: (i) the taxonomic identification of cyanobacteria found in these rivers, (ii) the environmental characterization of their habitats, and (iii) testing for the presence of toxin producing genes in the encountered taxa. Additionally, we introduce and discuss the use of the term "CyanoHAMs" for lotic water environments. Populations of cyanobacteria were collected from ten mountain rivers and identified using molecular techniques. Subsequently, these taxa were evaluated for genes producing anatoxins and microcystins via PCR. Through RDA analyses, the collected cyanobacteria were grouped into one of three categories based on their environmental preferences for the following: (1) waters with high ionic concentrations, (2) cold-temperate waters, or (3) waters with high nutrient enrichment. Populations from six locations were identified to genus level: Ancylothrix sp., Cyanoplacoma sp., and Oxynema sp. The latter was found to contain the gene that produces anatoxins and microcystins in siliceous rivers, while Oxynema tested positive for the gene that produces microcystins in calcareous rivers. Our results suggest that eutrophic environments are not necessarily required for toxin-producing cyanobacteria. Our records of Compactonostoc, Oxynema, and Ancylothrix represent the first for Mexico. Four taxa were identified to species level: Wilmottia aff. murrayi, Nostoc tlalocii, Nostoc montejanii, and Dichothrix aff. willei, with only the first testing positive using PCR for anatoxin and microcystin-producing genes in siliceous rivers. Due to the differences between benthic growths with respect to planktonic ones, we propose the adoption of the term Cyanobacterial Harmful Algal Mats (CyanoHAMs) as a more precise descriptor for future studies.


Asunto(s)
Toxinas Bacterianas , Cianobacterias , Tropanos , Microcistinas/análisis , Floraciones de Algas Nocivas , México , Toxinas Bacterianas/genética , Toxinas Bacterianas/análisis , Monitoreo del Ambiente , Cianobacterias/genética , Toxinas de Cianobacterias , Ríos/microbiología
10.
BMC Microbiol ; 23(1): 68, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36918804

RESUMEN

At particular stages during their life cycles, fungi use multiple strategies to form specialized structures to survive unfavorable environmental conditions. These strategies encompass sporulation, as well as cell-wall melanization, multicellular tissue formation or even dimorphism. The resulting structures are not only used to disperse to other environments, but also to survive long periods of time awaiting favorable growth conditions. As a result, these specialized fungal structures are part of the microbial seed bank, which is known to influence the microbial community composition and contribute to the maintenance of diversity. Despite the importance of the microbial seed bank in the environment, methods to study the diversity of fungal structures with improved resistance only target spores dispersing in the air, omitting the high diversity of these structures in terms of morphology and environmental distribution. In this study, we applied a separation method based on cell lysis to enrich lysis-resistant fungal structures (for instance, spores, sclerotia, melanized yeast) to obtain a proxy of the composition of the fungal seed bank. This approach was first evaluated in-vitro in selected species. The results obtained showed that DNA from fungal spores and from yeast was only obtained after the application of the enrichment method, while mycelium was always lysed. After validation, we compared the diversity of the total and lysis-resistant fractions in the polyextreme environment of the Salar de Huasco, a high-altitude athalassohaline wetland in the Chilean Altiplano. Environmental samples were collected from the salt flat and from microbial mats in small surrounding ponds. Both the lake sediments and microbial mats were dominated by Ascomycota and Basidiomycota, however, the diversity and composition of each environment differed at lower taxonomic ranks. Members of the phylum Chytridiomycota were enriched in the lysis-resistant fraction, while members of the phylum Rozellomycota were never detected in this fraction. Moreover, we show that the community composition of the lysis-resistant fraction reflects the diversity of life cycles and survival strategies developed by fungi in the environment. To the best of our knowledge this is the first time that the fungal diversity is explored in the Salar de Huasco. In addition, the method presented here provides a simple and culture independent approach to assess the diversity of fungal lysis-resistant cells in the environment.


Asunto(s)
ADN de Hongos , Hongos , Sedimentos Geológicos , Micobioma , Esporas Fúngicas , Ascomicetos/genética , Ascomicetos/fisiología , Basidiomycota/genética , Basidiomycota/fisiología , Chile , Hongos/genética , Hongos/fisiología , Sedimentos Geológicos/microbiología , Lagos/microbiología , Microbiota/fisiología , Micelio/genética , Micelio/aislamiento & purificación , Micelio/fisiología , Micobioma/fisiología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiología , Esporas Fúngicas/genética , Esporas Fúngicas/aislamiento & purificación , Esporas Fúngicas/fisiología , Humedales , ADN de Hongos/genética , ADN de Hongos/aislamiento & purificación , ADN de Hongos/fisiología
11.
Microb Ecol ; 86(3): 1632-1645, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36750476

RESUMEN

While microbial communities in limestone caves across the world are relatively understood, knowledge of the microbial composition in lava tubes is lagging behind. These caves are found in volcanic regions worldwide and are typically lined with multicolored microbial mats on their walls and ceilings. The Mount Etna (Sicily, S-Italy) represents one of the most active volcanos in the world. Due to its outstanding biodiversity and geological features, it was declared Natural Heritage of Humanity by the UNESCO in 2013. Despite the presence of more than 200 basaltic lava tubes, the microbial diversity of these hypogean systems has never been investigated so far. Here, we investigated bacterial communities in four lava tubes of Mount Etna volcano. Field emission scanning electron microscopy (FESEM) was carried out for the morphological characterization and detection of microbial features. We documented an abundant presence of microbial cells with different morphotypes including rod-shaped, filamentous, and coccoidal cells with surface appendages, resembling actinobacteria reported in other lava tubes across the world. Based on 16S rRNA gene analysis, the colored microbial mats collected were mostly composed of bacteria belonging to the phyla Actinomycetota, Pseudomonadota, Acidobacteriota, Chloroflexota, and Cyanobacteria. At the genus level, the analysis revealed a dominance of the genus Crossiella, which is actively involved in biomineralization processes, followed by Pseudomonas, Bacillus, Chujaibacter, and Sphingomonas. The presence of these taxa is associated with the carbon, nitrogen, and ammonia cycles, and some are possibly related to the anthropic disturbance of these caves. This study provides the first insight into the microbial diversity of the Etna volcano lava tubes, and expands on previous research on microbiology of volcanic caves across the world.


Asunto(s)
Cuevas , Microbiota , Cuevas/microbiología , ARN Ribosómico 16S/genética , Bacterias/genética , Biodiversidad , Filogenia
12.
Environ Sci Technol ; 57(14): 5646-5654, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-36988557

RESUMEN

Formamide has been classified as a Class 1B reproductive toxicant to children by the European Union (EU) Chemicals Agency. Foam mats are a potential source of formamide and ammonia. Online dopant-assisted atmospheric pressure photoionization time-of-flight mass spectrometry (DA-APPI-TOFMS) coupled with a Teflon environmental chamber was developed to assess the exposure risk of formamide and ammonia from foam mats to children. High levels of formamide (average 3363.72 mg/m3) and ammonia (average 1586.78 mg/m3) emissions were measured from 21 foam mats with three different raw material types: ethylene-vinyl acetate (EVA: n = 7), polyethylene (PE: n = 7), and cross-linked polyethylene (XPE: n = 7). The 28 day emission testing for the selected PE mat showed that the emissions of formamide were 2 orders of magnitude higher than the EU emission limit of 20 µg/m3, and formamide may be a permanent indoor contaminant for foam mat products during their life cycle. The exposure assessment of children aged 0.5-6 years showed that the exposure dose was approximately hundreds of mg/kg-day, and the age group of 0.5-2 years was subject to much higher dermal exposures than others. Thus, this study provided key relevant information for further studies on assessing children's exposure to indoor air pollution from foam mats.


Asunto(s)
Contaminación del Aire Interior , Amoníaco , Humanos , Niño , Lactante , Preescolar , Amoníaco/análisis , Contaminación del Aire Interior/análisis , Formamidas/análisis , Polietilenos/análisis
13.
J Phycol ; 59(3): 619-634, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37073408

RESUMEN

Cyanobacteria are diverse prokaryotic, photosynthetic organisms present in nearly every known ecosystem. Recent investigations around the world have recovered vast amounts of novel biodiversity in seldom sampled habitats. One phylogenetically significant character, the secondary folding structures of the 16S-23S ITS rDNA region, has allowed an unprecedented capacity to erect new species. However, two questions arise: Is this feature as informative as is proposed, and how do we best employ these features? Submerged sinkholes with oxygen-poor, sulfur-rich ground water in Lake Huron (USA) contain microbial mats dominated by both oxygenic and anoxygenic cyanobacteria. We sought to document some of this unique cyanobacterial diversity. Using culture-based investigations, we recovered 45 strains, of which 23 were analyzed employing 16S-23S rDNA sequences, ITS folding patterns, ecology, and morphology. With scant morphological discontinuities and nebulous 16S rDNA gene sequence divergence, ITS folding patterns were effective at articulating cryptic biodiversity. However, we would have missed these features had we not folded all the available motifs from the strains, including those with highly similar 16S rDNA gene sequences. If we had relied solely on morphological or 16S rDNA gene data, then we might well have missed the diversity of Anagnostidinema. Thus, in order to avoid conformation basis, which is potentially common when employing ITS structures, we advocate clustering strains based on ITS rDNA region patterns independently and comparing them back to 16S rDNA gene phylogenies. Using a total evidence approach, we erected a new taxon according to the International Code of Nomenclature for Algae, Fungi, and Plants: Anagnostidinema visiae.


Asunto(s)
Cianobacterias , Ecosistema , Cianobacterias/genética , Filogenia , Biodiversidad , ADN Ribosómico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
14.
Chem Biodivers ; : e202300829, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37721179

RESUMEN

Microbial mats are microbial communities capable of recycling the essential elements of life and considered to be the oldest evidence of microbial communities on Earth. Due to their uniqueness and limited sampling material, analyzing their metabolomic profile in different seasons or conditions is challenging. In this study, microbial mats from a small pond in the Cuatro Cienegas Basin in Coahuila, Mexico, were collected in wet and dry seasons. In addition to these samples, mesocosm experiments from the wet samples were set. These mats are elastic and rise after heavy rainfall by forming gas domes structures known as "Archean domes", by the outgassing of methanogenic bacteria, archaea, and sulfur bacteria. Extracts from all mats and mesocosms were subjected to untargeted mass spectrometry-based metabolomics and molecular networking analysis. Interestingly, each mat showed high chemical diversity that may be explained by the temporal dynamic processes in which they were sampled.

15.
J Appl Res Intellect Disabil ; 36(1): 39-49, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36124783

RESUMEN

BACKGROUND: Views on social care related quality of life (SCRQol) are typically gathered directly from individuals or from proxy informants. Easy-read options are available, although such methods may not be accessible to those with greater communication challenges. METHODS: Fifteen people with intellectual disabilities were interviewed about their SCRQoL using Talking Mats® (TM). A descriptive approach was taken to exploring what people had to say. RESULTS: Participants reported high levels of satisfaction with living conditions and personal care routines. They were mostly satisfied with the level of choice and control they had and with their carers. CONCLUSIONS: People with intellectual disabilities who have greater communication challenges can make meaningful contributions to the assessment of the care they receive. Talking Mats is one tool which can be used to support people with intellectual disabilities to give their views.


Asunto(s)
Discapacidad Intelectual , Adulto , Humanos , Calidad de Vida , Apoyo Social , Cuidadores , Apoderado
16.
Environ Monit Assess ; 195(12): 1475, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37966584

RESUMEN

The Neptune's cup sponge is an iconic species found in marine soft sediment habitats in the Indo-West Pacific, with a history of overharvesting and extreme population declines. Access to SCUBA diving surveys has allowed for its rediscovery at Singapore, its type locality; however, with fewer than ten living individuals documented in the twenty-first century, the species is believed to be in need of conservation. Here, we share the results from surveys across the Gulf of Thailand, allowing for a documentation of 29 additional individuals, with information on their ecology and distribution. Of the 29 individuals, extensive damage or mortality caused by marine debris is recorded for six individuals, and one further individual is believed to be lost due to an unknown cause. Documented threats from the Gulf of Thailand differ from those in Singapore; however, low population sizes and poor connectivity remain a significant concern for the survival of the species.


Asunto(s)
Gastrópodos , Poríferos , Humanos , Animales , Tailandia , Neptuno , Monitoreo del Ambiente , Ecología
17.
Small ; 18(13): e2107156, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35146894

RESUMEN

Solar desalination has been recognized as an emerging strategy for solving the pressing global freshwater crisis. However, salt crystallization at the photothermal interface frequently causes evaporator failure. In addition, arbitrary discharge of concentrated brine produced during desalination results in potential ecological impacts as well as wastage of valuable minerals. In the present work, a suspended-type evaporator (STEs) constructed using Janus fibrous mats is reported. The fibrous structure wicks brine to the evaporation layer and the salt gets confined in the evaporation layer until crystallization for zero liquid discharge due to the suspended design. Enhanced evaporation is observed because STEs have an additional low-resistance vapor escape path directly from the evaporation layer to the atmosphere compared to traditional floating Janus evaporators. Moreover, owing to the drastically different wettability on both sides, the evaporator allows salt crystallization only on the hydrophilic bottom layer, thus eliminating salt accumulation at the hydrophobic photothermal interface. With this unique structural design, the proposed evaporator not only maintains a high evaporation rate of 1.94 kg m-2 h-1 , but also demonstrates zero liquid discharged salt resistance and ideal recovery of the mineral in brine.


Asunto(s)
Purificación del Agua , Interacciones Hidrofóbicas e Hidrofílicas , Cloruro de Sodio , Luz Solar
18.
Microb Ecol ; 83(1): 1-17, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33730193

RESUMEN

The wetlands and salt flats of the Central Andes region are unique extreme environments as they are located in high-altitude saline deserts, largely influenced by volcanic activity. Environmental factors, such as ultraviolet (UV) radiation, arsenic content, high salinity, low dissolved oxygen content, extreme daily temperature fluctuation, and oligotrophic conditions, resemble the early Earth and potentially extraterrestrial conditions. The discovery of modern microbialites and microbial mats in the Central Andes during the past decade has increased the interest in this area as an early Earth analog. In this work, we review the current state of knowledge of Central Andes region environments found within lakes, small ponds or puquios, and salt flats of Argentina, Chile, and Bolivia, many of them harboring a diverse range of microbial communities that we have termed Andean Microbial Ecosystems (AMEs). We have integrated the data recovered from all the known AMEs and compared their biogeochemistry and microbial diversity to achieve a better understanding of them and, consequently, facilitate their protection.


Asunto(s)
Microbiota , Humedales , Sedimentos Geológicos/química , Lagos/química , Salinidad
19.
Mol Breed ; 42(7): 40, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37313507

RESUMEN

Grain hardness (HI) is a key trait for wheat milling and end-use quality. Puroindoline genes (PINs) are the major genes responsible for grain hardness, but other QTLs also contribute to the trait. Therefore, it is essential to identify loci associated with the HI and allelic variations of PINs in wheat. In the present study, 287 accessions from Shanxi province representing 70 years of wheat breeding were grown in one rainfed and two irrigated conditions to study grain hardness. Genome-wide association analysis (GWAS) was performed using the 15 K array, and the variability of PIN alleles was investigated. Among the accessions, hard wheat was most common. The broad-sense heritability (H2) among the three environments was 99.5%, suggesting HI was mainly affected by heredity. GWAS identified nine significant marker-trait associations (MTAs), including that PINs, which explained 7.03% to 17.70% of phenotypic variation. Four MTAs on chromosome 2A, 2B, 5A, and 7A were novel loci. As for diversity of PINs, a total of 11 PINs haplotypes were detected, composed of 12 allelic variations of the PIN gene. The most frequent haplotypes were Pina-D1a/Pinb-D1b (43.9%) and Pina-Dla/Pinb-D1p (18.8%), and both the frequency of Pina-D1a/Pinb-D1b and the HI value increased with breeding years were related to local dietary habits probably. A novel double deletion allele of the PINs haplotype was found in Donghei1206. These results will be useful not only in understanding of the genetics of the HI but also in breeding for improved grain texture. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01303-x.

20.
Mol Phylogenet Evol ; 160: 107010, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33186689

RESUMEN

Benthic cyanobacterial mats are an integral component of aquatic communities in tropical marine waters. These mats can develop into massive nuisances at risk of expansion due to climate change. The extent of diversity occurring within these mats, still remains largely unexplored, especially in Florida. To reveal this diversity, coastal environments of South Florida were sampled and subsequently processed for isolation and systematic identification. Three new genera are proposed based on the molecular phylogeny, morphology, and ecology. These new genera are characterized by discoid cells and homocytous, unbranched filaments without sheaths. Individual genus morphological differences include either rounded bent, rounded, or conical rounded apical cells. A unique molecular fingerprint including a base pair insert within the 16S rRNA gene sequence and genetic similarities facilitates the delimitation of a novel family Vermifilaceae. Using the polyphasic approach, our research presents three new genera and four new species of marine cyanobacteria inhabiting coastal ecosystems of South Florida.


Asunto(s)
Organismos Acuáticos , Cianobacterias/clasificación , Cianobacterias/genética , Ecosistema , Filogenia , Organismos Acuáticos/clasificación , Organismos Acuáticos/genética , ADN Bacteriano/genética , Florida , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
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