Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Am Assoc Nurse Pract ; 36(2): 94-99, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37698516

RESUMO

ABSTRACT: Nurse practitioners (NPs) are well positioned to provide inclusive, person-centered care to patients who are transgender and gender diverse (TGD); however, few NPs have been trained on how to do so. This study demonstrates the longitudinal effect of an educational intervention that used readings, lecture, a patient panel, and a standardized patient encounter on NPs' and nurse practitioner students' cultural competency, knowledge, skills, and attitudes toward patients who are TGD. The study followed participants for 3 months and used the Sexual Orientation Counselor Competency Scale version 3 tool to measure changes across three data points. Significant improvements were demonstrated in cultural competency and clinical skills, with knowledge and attitude increases that did not reach significances. The findings from this study have implications for the inclusion of TGD content in graduate nursing curriculum and continuing education activities and provide educators with best practices to integrate this content into learning activities.


Assuntos
Profissionais de Enfermagem , Pessoas Transgênero , Humanos , Masculino , Feminino , Competência Cultural/educação , Currículo , Profissionais de Enfermagem/educação , Estudantes , Competência Clínica
2.
Artigo em Inglês | MEDLINE | ID: mdl-38076031

RESUMO

This study characterizes the effects of three commonly detected pharmaceuticals-diclofenac, erythromycin, and gemfibrozil-on aerobic granular sludge. Approximately 150 µg/L of each pharmaceutical was fed in the influent to a sequencing batch reactor for 80 days, and the performance of the test reactor was compared with that of a control reactor. Wastewater treatment efficacy in the test reactor dropped by approximately 30-40%, and ammonia oxidation was particularly inhibited. The relative abundance of active Rhodocyclaceae, Nitrosomonadaceae, and Nitrospiraceae families declined throughout exposure, likely explaining reductions in wastewater treatment performance. Pharmaceuticals were temporarily removed in the first 12 days of the test via both sorption and degradation; both removal processes declined sharply thereafter. This study demonstrates that aerobic granular sludge may successfully remove pharmaceuticals in the short term, but long-term tests are necessary to confirm if pharmaceutical removal is sustainable.

3.
Biofilm ; 5: 100127, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37252227

RESUMO

While life on Mars has not been found, Earth-based microorganisms may contaminate the Red Planet during rover expeditions and human exploration. Due to the survival advantages conferred by the biofilm morphology to microorganisms, such as resistance to UV and osmotic stress, biofilms are particularly concerning from a planetary protection perspective. Modeling and data from the NASA Phoenix mission indicate that temporary liquid water might exist on Mars in the form of high salinity brines. These brines could provide colonization opportunities for terrestrial microorganisms brought by spacecraft or humans. To begin testing for potential establishment of microbes, results are presented from a simplified laboratory model of a Martian saline seep inoculated with sediment from Hailstone Basin, a terrestrial saline seep in Montana (USA). The seep was modeled as a sand-packed drip flow reactor at room temperature fed media with either 1 M MgSO4 or 1 M NaCl. Biofilms were established within the first sampling point of each experiment. Endpoint 16S rRNA gene community analysis showed significant selection of halophilic microorganisms by the media. Additionally, we detected 16S rRNA gene sequences highly similar to microorganisms previously detected in two spacecraft assembly cleanrooms. These experimental models provide an important foundation for identifying microbes that could hitch-hike on spacecraft and may be able to colonize Martian saline seeps. Future model optimization will be vital to informing cleanroom sterilization procedures.

4.
Nurse Educ ; 48(6): 304-309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37104051

RESUMO

BACKGROUND: An increasing number of individuals who identify as transgender and gender diverse require informed and compassionate health care, yet there is a dearth of research about which educational strategies are best used to provide nurses and nurse practitioners the foundation upon which to provide appropriate health care. PURPOSE: This study evaluated a multimodal approach that included guided readings, a transgender patient panel, standardized patient simulation, and group discussion. METHODS: The Sexual Orientation Counselor Competency Scale was administered pre- and postintervention. RESULTS: Results demonstrated increases in knowledge, skills, and attitudes among the 16 participants. A high level of satisfaction was expressed for the overall program, but especially for the patient panel and standardized patient encounter. CONCLUSIONS: Nurse educators are encouraged to include information about health care of the transgender patient into curricula.


Assuntos
Profissionais de Enfermagem , Pessoas Transgênero , Humanos , Masculino , Feminino , Pesquisa em Educação em Enfermagem , Currículo , Profissionais de Enfermagem/educação , Estudantes , Atenção Primária à Saúde
5.
Sci Rep ; 12(1): 18707, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333441

RESUMO

Research focused on microbial populations of thermoalkaline springs has been driven in a large part by the lure of discovering functional enzymes with industrial applications in high-pH and high temperature environments. While several studies have focused on understanding the fundamental ecology of these springs, the small molecule profiles of thermoalkaline springs have largely been overlooked. To better understand how geochemistry, small molecule composition, and microbial communities are connected, we conducted a three-year study of the Five Sisters (FS) springs that included high-resolution geochemical measurements, 16S rRNA sequencing of the bacterial and archaeal community, and mass spectrometry-based metabolite and extracellular small molecule characterization. Integration of the four datasets facilitated a comprehensive analysis of the interwoven thermoalkaline spring system. Over the course of the study, the microbial population responded to changing environmental conditions, with archaeal populations decreasing in both relative abundance and diversity compared to bacterial populations. Decreases in the relative abundance of Archaea were associated with environmental changes that included decreased availability of specific nitrogen- and sulfur-containing extracellular small molecules and fluctuations in metabolic pathways associated with nitrogen cycling. This multi-factorial analysis demonstrates that the microbial community composition is more closely correlated with pools of extracellular small molecules than with the geochemistry of the thermal springs. This is a novel finding and suggests that a previously overlooked component of thermal springs may have a significant impact on microbial community composition.


Assuntos
Fontes Termais , Feminino , Humanos , Fontes Termais/microbiologia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Parques Recreativos , Filogenia , Archaea , Bactérias/genética , Nitrogênio/metabolismo
6.
Sci Rep ; 12(1): 12581, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869127

RESUMO

Plant survival during environmental stress greatly affects ecosystem carbon (C) cycling, and plant-microbe interactions are central to plant stress survival. The release of C-rich root exudates is a key mechanism plants use to manage their microbiome, attracting beneficial microbes and/or suppressing harmful microbes to help plants withstand environmental stress. However, a critical knowledge gap is how plants alter root exudate concentration and composition under varying stress levels. In a greenhouse study, we imposed three drought treatments (control, mild, severe) on blue grama (Bouteloua gracilis Kunth Lag. Ex Griffiths), and measured plant physiology and root exudate concentration and composition using GC-MS, NMR, and FTICR. With increasing drought severity, root exudate total C and organic C increased concurrently with declining predawn leaf water potential and photosynthesis. Root exudate composition mirrored the physiological gradient of drought severity treatments. Specific compounds that are known to alter plant drought responses and the rhizosphere microbiome mirrored the drought severity-induced root exudate compositional gradient. Despite reducing C uptake, these plants actively invested C to root exudates with increasing drought severity. Patterns of plant physiology and root exudate concentration and composition co-varied along a gradient of drought severity.


Assuntos
Secas , Microbiota , Exsudatos e Transudatos , Raízes de Plantas/fisiologia , Plantas , Poaceae , Rizosfera
8.
Phys Fluids (1994) ; 34(3): 031910, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35392485

RESUMO

The Food and Drug Administration recommends against washing raw chicken due to the risk of transferring dangerous food-borne pathogens through splashed drops of water. Many cooks continue to wash raw chicken despite this warning, however, and there is a lack of scientific research assessing the extent of microbial transmission in splashed droplets. Here, we use large agar plates to confirm that bacteria can be transferred from the surface of raw chicken through splashing. We also identify and create a phylogenetic tree of the bacteria present on the chicken and the bacteria transferred during splashing. While no food-borne pathogens were identified, we note that organisms in the same genera as pathogens were transferred from the chicken surface through these droplets. Additionally, we show that faucet height, flow type, and surface stiffness play a role in splash height and distance. Using high-speed imaging to explore splashing causes, we find that increasing faucet height leads to a flow instability that can increase splashing. Furthermore, splashing from soft materials such as chicken can create a divot in the surface, leading to splashing under flow conditions that would not splash on a curved, hard surface. Thus, we conclude that washing raw chicken does risk pathogen transfer and cross-contamination through droplet ejection, and that changing washing conditions can increase or decrease the risk of splashing.

9.
Appl Environ Microbiol ; 88(1): e0095821, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34669438

RESUMO

The microbial degradation of lignocellulose in natural ecosystems presents numerous biotechnological opportunities, including biofuel production from agricultural waste and feedstock biomass. To explore the degradation potential of specific thermophiles, we have identified and characterized extremophilic microorganisms isolated from hot springs environments that are capable of biodegrading lignin and cellulose substrates under thermoalkaline conditions, using a combination of culturing, genomics, and metabolomics techniques. Organisms that can use lignin and cellulose as a sole carbon source at 60 to 75°C were isolated from sediment slurry of thermoalkaline hot springs (71 to 81°C and pH 8 to 9) of Yellowstone National Park. Full-length 16S rRNA gene sequencing indicated that these isolates were closely related to Geobacillus thermoleovorans. Interestingly, most of these isolates demonstrated biofilm formation on lignin, a phenotype that is correlated with increased bioconversion. Assessment of metabolite level changes in two Geobacillus isolates from two representative springs were undertaken to characterize the metabolic responses associated with growth on glucose versus lignin carbon source as a function of pH and temperature. Overall, results from this study support that thermoalkaline springs harbor G. thermoleovorans microorganisms with lignocellulosic biomass degradation capabilities and potential downstream biotechnological applications. IMPORTANCE Since lignocellulosic biomass represents a major agro-industrial waste and renewable resource, its potential to replace nonrenewable petroleum-based products for energy production is considerable. Microbial ligninolytic and cellulolytic enzymes are of high interest in biorefineries for the valorization of lignocellulosic biomass, as they can withstand the extreme conditions (e.g., high temperature and high pH) required for processing. Of great interest is the ligninolytic potential of specific Geobacillus thermoleovorans isolates to function at a broad range of pH and temperatures, since lignin is the bottleneck in the bioprocessing of lignocellulose. In this study, results obtained from G. thermoleovorans isolates originating from YNP springs are significant because very few microorganisms from alkaline thermal environments have been discovered to have lignin- and cellulose-biodegrading capabilities, and this work opens new avenues for the biotechnological valorization of lignocellulosic biomass at an industrial scale.


Assuntos
Geobacillus , Lignina , Biomassa , Ecossistema , Geobacillus/genética , Parques Recreativos , RNA Ribossômico 16S/genética
10.
Mycologia ; 113(6): 1181-1198, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34686124

RESUMO

High temperatures and extended drought in temperate and tropical arid ecosystems promote the colonization of diverse microenvironments by dark septate fungi (DSF). These fungi contribute to soil nutrient cycling, soil stabilization, and plant survival, but the roles of individual DSF species, their distributions, and their community diversity are poorly understood. The objective of this study was to evaluate the distribution, seasonal variation, and potential roles of DSF on plant growth. We collected biocrust (lichen-, moss-, and cyanobacterium-dominated biocrusts) soils at different depths and rhizosphere soils from two grasses, Bromus tectorum and Pleuraphis jamesii, in an arid grassland near Moab, Utah, USA. Seasonal variation of DSF was evaluated using culture-based approaches and compared with fungal community profiles from next-generation sequencing (NGS). Culturing showed that DSF were 30% more abundant in biocrusts compared with the focal rhizospheres. The abundance of DSF varied seasonally in belowground samples (rhizosphere and below-biocrust), with a significant increase during the summer months. Pleosporales was the dominant order (35%) in both biocrust and rhizosphere soils out of 817 isolated fungi. Dominant DSF genera in culture included Alternaria, Preussia, Cladosporium, Phoma, and an unknown Pleosporales. Similar results were observed in biocrust and rhizosphere soils NGS. Further, seed germination experiments using dominant taxa were conducted to determine their potential roles on germination and seedling growth using maize as a model plant. Cladosporium and unknown Pleosporales isolates showed plant growth-promoting ability. The variation in abundance of DSF, their differential occurrence in different microenvironments, and their ability to grow in a xerotolerant medium reflect adaptations to summer environmental conditions and to changes in the abundance of organic matter, as well as a potential increase in plant investment in these fungi when heat and drought stresses are more severe.


Assuntos
Ascomicetos , Ecossistema , Fungos , Pradaria , Plantas , Poaceae/microbiologia , Estações do Ano , Solo , Microbiologia do Solo
11.
FEMS Microbiol Ecol ; 97(2)2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33501490

RESUMO

The described diversity within the domain Archaea has recently expanded due to advances in sequencing technologies, but many habitats that likely harbor novel lineages of archaea remain understudied. Knowledge of archaea within natural and engineered hydrothermal systems, such as hot springs and engineered subsurface habitats, has been steadily increasing, but the majority of the work has focused on archaea living in acidic or circumneutral environments. The environmental pressures exerted by the combination of high temperatures and high pH likely select for divergent communities and distinct metabolic pathways from those observed in acidic or circumneutral systems. In this review, we examine what is currently known about the archaea found in thermoalkaline environments, focusing on the detection of novel lineages and knowledge of the ecology, metabolic pathways and functions of these populations and communities. We also discuss the potential of emerging multi-omics approaches, including proteomics and metabolomics, to enhance our understanding of archaea within extreme thermoalkaline systems.


Assuntos
Archaea , Fontes Termais , Archaea/genética , Bactérias , Ecologia , Ecossistema , Filogenia
12.
Front Microbiol ; 11: 542220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240225

RESUMO

Discovering widespread microbial processes that drive unexpected variation in carbon cycling may improve modeling and management of soil carbon (Prescott, 2010; Wieder et al., 2015a, 2018). A first step is to identify community features linked to carbon cycle variation. We addressed this challenge using an epidemiological approach with 206 soil communities decomposing Ponderosa pine litter in 618 microcosms. Carbon flow from litter decomposition was measured over a 6-week incubation. Cumulative CO2 from microbial respiration varied two-fold among microcosms and dissolved organic carbon (DOC) from litter decomposition varied five-fold, demonstrating large functional variation despite constant environmental conditions where strong selection is expected. To investigate microbial features driving DOC concentration, two microbial community cohorts were delineated as "high" and "low" DOC. For each cohort, communities from the original soils and from the final microcosm communities after the 6-week incubation with litter were taxonomically profiled. A logistic model including total biomass, fungal richness, and bacterial richness measured in the original soils or in the final microcosm communities predicted the DOC cohort with 72 (P < 0.05) and 80 (P < 0.001) percent accuracy, respectively. The strongest predictors of the DOC cohort were biomass and either fungal richness (in the original soils) or bacterial richness (in the final microcosm communities). Successful forecasting of functional patterns after lengthy community succession in a new environment reveals strong historical contingencies. Forecasting future community function is a key advance beyond correlation of functional variance with end-state community features. The importance of taxon richness-the same feature linked to carbon fate in gut microbiome studies-underscores the need for increased understanding of biotic mechanisms that can shape richness in microbial communities independent of physicochemical conditions.

13.
Microbiol Res ; 239: 126530, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32622287

RESUMO

Soil fungi in desert ecosystems are adapted to harsh environmental conditions such as high soil surface temperatures and limited organic matter and water. Given limited carbon inputs from plant material, heterotrophic fungi likely use unconventional sources of carbon in these systems. A baiting method was used to culture keratinophilic fungi from biocrust and rhizosphere soils in an arid grassland in Utah, USA. Fungi were baited using llama and sheep wool, horsehair, and snakeskin on two media, and pure cultures were identified using ITS and LSU rRNA sequences. One hundred-eighteen fungal colonies were grown, representing a total of 32 Operational Taxonomic Units (OTUs) at 97 % similarity. Cultures were dominated by the phylum Ascomycota (88 %) followed by Mucoromycota (8.6 %) and Basidiomycota (3.4 %). The orders Pleosporales, Eurotiales, Hypocreales, and Sordariales were commonly isolated, with the dominant taxa Alternaria (27 %), Aspergillus (22 %), Fusarium (11 %), and Chaetomium (8%). Thirty percent of the fungi isolated have the capacity to degrade keratin in vitro using a keratin azure assay, with Penicillium showing the highest degradation followed by Geomyces, Alternaria, and Fusarium. Although keratin degraders can be infectious, dermatophytes associated with skin infections were not isolated in culture or detected in Illumina sequencing. Illumina sequencing was used to determine general patterns in seasonal variation and habitat preference of keratinophiles. Alternaria was the most abundant genus with >70 % of the sequences. The combination of Illumina data with culture-dependent approaches facilitated the characterization of a specialized community and confirmed the low abundance of dermatophytes in this arid site.


Assuntos
Ecossistema , Fungos/classificação , Queratinas/metabolismo , Micobioma , Microbiologia do Solo , Biodiversidade , Contagem de Colônia Microbiana , Clima Desértico , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Rizosfera , Estações do Ano
14.
Comput Inform Nurs ; 38(2): 71-79, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31804242

RESUMO

Patients frequently download mHealth apps, which can be used to support health promotion. It remains unclear, however, if family nurse practitioners are recommending apps to patients. This study identified family nurse practitioners' current practices of recommending apps to patients and described their use and intent to use mHealth apps for health promotion with their patients. Nearly 70% of the 303 participants surveyed recommended mHealth apps to their patients, with the most common types comprising patient portal, diet and nutrition, and fitness apps. However, the frequency with which apps were recommended was low. Participants reported that apps complement patient care, enable health promotion behaviors, are easy to use, and improve clarity of patient data. These factors facilitated their intent to recommend mHealth apps to patients. Healthcare organizational support influenced participants' intent to recommend apps, and access to trustworthy apps and electronic health records compatibility increased usage. Barriers to recommending involved patient-specific characteristics and provider concerns about reliability, privacy, and efficacy of apps. Family nurse practitioners must be supported in guiding patients to use reliable, safe, and HIPAA-compliant apps. To help engage patients, clinicians should be educated on methods to evaluate mHealth apps and how to incorporate them into patient care.


Assuntos
Enfermeiros de Saúde da Família , Promoção da Saúde , Aplicativos Móveis , Encaminhamento e Consulta , Telemedicina , Comportamentos Relacionados com a Saúde , Humanos , Internet , Inquéritos e Questionários , Estados Unidos
15.
New Phytol ; 224(1): 155-165, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31209891

RESUMO

Successive droughts have resulted in extensive tree mortality in the southwestern United States. Recovery of these areas is dependent on the survival and recruitment of young trees. For trees that rely on ectomycorrhizal fungi (EMF) for survival and growth, changes in soil fungal communities following tree mortality could negatively affect seedling establishment. We used tree-focused and stand-scale measurements to examine the impact of pinyon pine mortality on the performance of surviving juvenile trees and the potential for mutualism limitation of seedling establishment via altered EMF communities. Mature pinyon mortality did not affect the survival of juvenile pinyons, but increased their growth. At both tree and stand scales, high pinyon mortality had no effect on the abundance of EMF inocula, but led to altered EMF community composition including increased abundance of Geopora and reduced abundance of Tuber. Seedling biomass was strongly positively associated with Tuber abundance, suggesting that reductions in this genus with pinyon mortality could have negative consequences for establishing seedlings. These findings suggest that whereas mature pinyon mortality led to competitive release for established juvenile pinyons, changes in EMF community composition with mortality could limit successful seedling establishment and growth in high-mortality sites.


Assuntos
Micorrizas/fisiologia , Pinus/microbiologia , Árvores/microbiologia , Biomassa , Microclima , Caules de Planta/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Plântula/microbiologia
16.
Environ Microbiol ; 19(4): 1600-1611, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28120480

RESUMO

Nitrogen (N) deposition affects myriad aspects of terrestrial ecosystem structure and function, and microbial communities may be particularly sensitive to anthropogenic N inputs. However, our understanding of N deposition effects on microbial communities is far from complete, especially for drylands where data are comparatively rare. To address the need for an improved understanding of dryland biological responses to N deposition, we conducted a two-year fertilization experiment in a semiarid grassland on the Colorado Plateau in the southwestern United States. We evaluated effects of varied levels of N inputs on archaeal, bacterial, fungal and chlorophyte community composition within three microhabitats: biological soil crusts (biocrusts), soil below biocrusts, and the plant rhizosphere. Surprisingly, N addition did not affect the community composition or diversity of any of these microbial groups; however, microbial community composition varied significantly among sampling microhabitats. Further, while plant richness, diversity, and cover showed no response to N addition, there were strong linkages between plant properties and microbial community structure. Overall, these findings highlight the potential for some dryland communities to have limited biotic ability to retain augmented N inputs, possibly leading to large N losses to the atmosphere and to aquatic systems.


Assuntos
Pradaria , Nitrogênio/metabolismo , Microbiologia do Solo , Archaea , Biomassa , Colorado , Ecossistema , Fungos/metabolismo , Plantas/metabolismo , Rizosfera , Solo/química
17.
Microb Ecol ; 71(1): 57-67, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26280745

RESUMO

Dormancy is thought to promote biodiversity within microbial communities, but how assembly of the active community responds to changes in environmental conditions is unclear. To measure the active and dormant communities of bacteria and fungi colonizing decomposing litter in maple forests, we targeted ribosomal genes and transcripts across a natural environmental gradient. Within bacterial and fungal communities, the active and dormant communities were phylogenetically distinct, but patterns of phylogenetic clustering varied. For bacteria, active communities were significantly more clustered than dormant communities, while the reverse was found for fungi. The proportion of operational taxonomic units (OTUs) classified as active and the degree of phylogenetic clustering of the active bacterial communities declined with increasing pH and decreasing C/N. No significant correlations were found for the fungal community. The opposing pattern of phylogenetic clustering in dormant and active communities and the differential response of active communities to environmental gradients suggest that dormancy differentially structures bacterial and fungal communities.


Assuntos
Acer/microbiologia , Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Acer/crescimento & desenvolvimento , Bactérias/classificação , Bactérias/genética , Biodiversidade , Florestas , Fungos/classificação , Fungos/genética , Filogenia , Folhas de Planta/microbiologia
18.
FEMS Microbiol Ecol ; 92(2)2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26656064

RESUMO

The inclusion of phylogenetic metrics in community ecology has provided insights into important ecological processes, particularly when combined with high-throughput sequencing methods; however, these approaches have not been widely used in studies of fungal communities relative to other microbial groups. Two obstacles have been considered: (1) the internal transcribed spacer (ITS) region has limited utility for constructing phylogenies and (2) most PCR primers that target the large subunit (LSU) ribosomal unit generate amplicons that exceed current limits of high-throughput sequencing platforms. We designed and tested a PCR primer (LR22R) to target approximately 300-400 bp region of the D2 hypervariable region of the fungal LSU for use with the Illumina MiSeq platform. Both in silico and empirical analyses showed that the LR22R-LR3 pair captured a broad range of fungal taxonomic groups with a small fraction of non-fungal groups. Phylogenetic placement of publically available LSU D2 sequences showed broad agreement with taxonomic classification. Comparisons of the LSU D2 and the ITS2 ribosomal regions from environmental samples and known communities showed similar discriminatory abilities of the two primer sets. Together, these findings show that the LR22R-LR3 primer pair has utility for phylogenetic analyses of fungal communities using high-throughput sequencing methods.


Assuntos
Primers do DNA/genética , Fungos/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Fúngico/genética , RNA Ribossômico/genética , Subunidades Ribossômicas Maiores/genética , Sequência de Bases , Biota , Fungos/classificação , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de RNA
19.
Front Microbiol ; 6: 891, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26388845

RESUMO

Arid shrublands are stressful environments, typified by alkaline soils low in organic matter, with biologically-limiting extremes in water availability, temperature, and UV radiation. The widely-spaced plants and interspace biological soil crusts in these regions provide soil nutrients in a localized fashion, creating a mosaic pattern of plant- or crust-associated microhabitats with distinct nutrient composition. With sporadic and limited rainfall, nutrients are primarily retained in the shallow surface soil, patterning biological activity. We examined soil bacterial and fungal community responses to simulated nitrogen (N) deposition in an arid Larrea tridentata-Ambrosia dumosa field experiment in southern Nevada, USA, using high-throughput sequencing of ribosomal RNA genes. To examine potential interactions among the N application, microhabitat and soil depth, we sampled soils associated with shrub canopies and interspace biological crusts at two soil depths (0-0.5 or 0-10 cm) across the N-amendment gradient (0, 7, and 15 kg ha(-1) yr(-1)). We hypothesized that localized compositional differences in soil microbiota would constrain the impacts of N addition to a microhabitat distribution that would reflect highly localized geochemical conditions and microbial community composition. The richness and community composition of both bacterial and fungal communities differed significantly by microhabitat and with soil depth in each microhabitat. Only bacterial communities exhibited significant responses to the N addition. Community composition correlated with microhabitat and depth differences in soil geochemical features. Given the distinct roles of soil bacteria and fungi in major nutrient cycles, the resilience of fungi and sensitivity of bacteria to N amendments suggests that increased N input predicted for many arid ecosystems could shift nutrient cycling toward pathways driven primarily by fungal communities.

20.
Front Microbiol ; 6: 779, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26284056

RESUMO

The Amazon rainforest is well known for its rich plant and animal diversity, but its bacterial diversity is virtually unexplored. Due to ongoing and widespread deforestation followed by conversion to agriculture, there is an urgent need to quantify the soil biological diversity within this tropical ecosystem. Given the abundance of the phylum Verrucomicrobia in soils, we targeted this group to examine its response to forest-to-pasture conversion. Both taxonomic and phylogenetic diversities were higher for pasture in comparison to primary and secondary forests. The community composition of Verrucomicrobia in pasture soils was significantly different from those of forests, with a 11.6% increase in the number of sequences belonging to subphylum 3 and a proportional decrease in sequences belonging to the class Spartobacteria. Based on 99% operational taxonomic unit identity, 40% of the sequences have not been detected in previous studies, underscoring the limited knowledge regarding the diversity of microorganisms in tropical ecosystems. The abundance of Verrucomicrobia, measured with quantitative PCR, was strongly correlated with soil C content (r = 0.80, P = 0.0016), indicating their importance in metabolizing plant-derived carbon compounds in soils.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...