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1.
Nucleic Acids Res ; 52(14): e63, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38909293

RESUMO

The microbiome is a complex community of microorganisms, encompassing prokaryotic (bacterial and archaeal), eukaryotic, and viral entities. This microbial ensemble plays a pivotal role in influencing the health and productivity of diverse ecosystems while shaping the web of life. However, many software suites developed to study microbiomes analyze only the prokaryotic community and provide limited to no support for viruses and microeukaryotes. Previously, we introduced the Viral Eukaryotic Bacterial Archaeal (VEBA) open-source software suite to address this critical gap in microbiome research by extending genome-resolved analysis beyond prokaryotes to encompass the understudied realms of eukaryotes and viruses. Here we present VEBA 2.0 with key updates including a comprehensive clustered microeukaryotic protein database, rapid genome/protein-level clustering, bioprospecting, non-coding/organelle gene modeling, genome-resolved taxonomic/pathway profiling, long-read support, and containerization. We demonstrate VEBA's versatile application through the analysis of diverse case studies including marine water, Siberian permafrost, and white-tailed deer lung tissues with the latter showcasing how to identify integrated viruses. VEBA represents a crucial advancement in microbiome research, offering a powerful and accessible software suite that bridges the gap between genomics and biotechnological solutions.


Assuntos
Software , Animais , Microbiota/genética , Biologia Computacional/métodos , Bactérias/genética , Bactérias/classificação , Vírus/genética , Vírus/classificação , Vírus/isolamento & purificação , Archaea/genética , Archaea/virologia , Genômica/métodos , Eucariotos/genética , Multiômica
2.
Sex Transm Infect ; 100(4): 242-250, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38754986

RESUMO

BACKGROUND: Partner notification (PN) is key to the control of sexually transmitted infections (STIs) and human immunodeficiency virus (HIV). Digital interventions have been used to facilitate PN. A scoping review was conducted to describe the interventions used, user preferences and acceptability of digital PN interventions from patient and partner perspectives. METHODS: A systematic literature search was conducted of eight databases for articles published in English, available online with digital PN outcome data. Articles were assessed using the Mixed Methods Appraisal Tool. Quantitative and qualitative data were synthesised and analysed using thematic analysis. RESULTS: Twenty-six articles met the eligibility criteria. Articles were heterogeneous in quality and design, with the majority using quantitative methods. Nine articles focused solely on bacterial STIs (five on syphilis; four on chlamydia), one on HIV, two on syphilis and HIV, and 14 included multiple STIs, of which 13 included HIV. There has been a shift over time from digital PN interventions solely focusing on notifying partners, to interventions including elements of partner management, such as facilitation of partner testing and treatment, or sharing of STI test results (between index patients and tested sex partners). Main outcomes measured were number of partners notified (13 articles), partner testing/consultation (eight articles) and treatment (five articles). Relationship type and STI type appeared to affect digital PN preferences for index patients with digital methods preferred for casual rather than established partner types. Generally, partners preferred face-to-face PN. CONCLUSION: Digital PN to date mainly focuses on notifying partners rather than comprehensive partner management. Despite an overall preference for face-to-face PN with partners, digital PN could play a useful role in improving outcomes for certain partner types and infections. Further research needs to understand the impact of digital PN interventions on specific PN outcomes, their effectiveness for different infections and include health economic evaluations.


Assuntos
Busca de Comunicante , Infecções por HIV , Parceiros Sexuais , Infecções Sexualmente Transmissíveis , Humanos , Busca de Comunicante/métodos , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções por HIV/prevenção & controle , Feminino , Masculino , Sífilis/prevenção & controle
3.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34799449

RESUMO

It is well established that mantle plumes are the main conduits for upwelling geochemically enriched material from Earth's deep interior. The fashion and extent to which lateral flow processes at shallow depths may disperse enriched mantle material far (>1,000 km) from vertical plume conduits, however, remain poorly constrained. Here, we report He and C isotope data from 65 hydrothermal fluids from the southern Central America Margin (CAM) which reveal strikingly high 3He/4He (up to 8.9RA) in low-temperature (≤50 °C) geothermal springs of central Panama that are not associated with active volcanism. Following radiogenic correction, these data imply a mantle source 3He/4He >10.3RA (and potentially up to 26RA, similar to Galápagos hotspot lavas) markedly greater than the upper mantle range (8 ± 1RA). Lava geochemistry (Pb isotopes, Nb/U, and Ce/Pb) and geophysical constraints show that high 3He/4He values in central Panama are likely derived from the infiltration of a Galápagos plume-like mantle through a slab window that opened ∼8 Mya. Two potential transport mechanisms can explain the connection between the Galápagos plume and the slab window: 1) sublithospheric transport of Galápagos plume material channeled by lithosphere thinning along the Panama Fracture Zone or 2) active upwelling of Galápagos plume material blown by a "mantle wind" toward the CAM. We present a model of global mantle flow that supports the second mechanism, whereby most of the eastward transport of Galápagos plume material occurs in the shallow asthenosphere. These findings underscore the potential for lateral mantle flow to transport mantle geochemical heterogeneities thousands of kilometers away from plume conduits.

4.
Sex Transm Infect ; 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701146

RESUMO

BACKGROUND: There has been considerable expansion in online postal self-sampling (OPSS) STI services in many parts of the UK, driven by increasing demand on sexual health services and developments in diagnostics and digital health provision. This shift in service delivery has occurred against a backdrop of reduced funding and service fragmentation and the impact is unknown. We explored characteristics of people accessing and using OPSS services for STIs in the UK, the acceptability of these services and their impact on sexual health inequalities. METHODS: A scoping review was conducted of studies published in English-language based on pre-agreed inclusion/exclusion criteria, between 01 January 2010 and 07 July 2021. Nine databases were searched, and 23 studies that met the eligibility criteria were included. Studies were appraised using the Mixed Methods Appraisal Tool. RESULTS: Study designs were heterogeneous, including quantitative, qualitative and mixed-methods analyses. The majority were either evaluating a single-site/self-sampling provider, exploratory or observational and of variable quality. Few studies collected comprehensive user demographic data. Individuals accessing OPSS tended to be asymptomatic, of white ethnicity, women, over 20 years and from less deprived areas. OPSS tended to increase overall STI testing demand and access, although return rates for blood samples were low, as was test positivity. There were varied results on whether services reduced time to treatment. OPSS services were acceptable to the majority of users. Qualitative studies showed the importance of trust, confidentiality, discretion, reliability, convenience and improved patient choice. CONCLUSION: OPSS services appear highly acceptable to users. However, uptake appears to be socially patterned and some groups who bear a disproportionate burden of poor sexual health in the UK are under-represented among users. Current provision of online self-sampling could widen health inequalities, particularly where other options for testing are limited. Work is needed to fully evaluate the impact and cost-effectiveness of OPSS services.

5.
Prenat Diagn ; 42(1): 49-59, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34648206

RESUMO

OBJECTIVE: Advances in artificial intelligence (AI) have demonstrated potential to improve medical diagnosis. We piloted the end-to-end automation of the mid-trimester screening ultrasound scan using AI-enabled tools. METHODS: A prospective method comparison study was conducted. Participants had both standard and AI-assisted US scans performed. The AI tools automated image acquisition, biometric measurement, and report production. A feedback survey captured the sonographers' perceptions of scanning. RESULTS: Twenty-three subjects were studied. The average time saving per scan was 7.62 min (34.7%) with the AI-assisted method (p < 0.0001). There was no difference in reporting time. There were no clinically significant differences in biometric measurements between the two methods. The AI tools saved a satisfactory view in 93% of the cases (four core views only), and 73% for the full 13 views, compared to 98% for both using the manual scan. Survey responses suggest that the AI tools helped sonographers to concentrate on image interpretation by removing disruptive tasks. CONCLUSION: Separating freehand scanning from image capture and measurement resulted in a faster scan and altered workflow. Removing repetitive tasks may allow more attention to be directed identifying fetal malformation. Further work is required to improve the image plane detection algorithm for use in real time.


Assuntos
Inteligência Artificial/normas , Anormalidades Congênitas/diagnóstico , Ultrassonografia Pré-Natal/instrumentação , Adulto , Inteligência Artificial/tendências , Anormalidades Congênitas/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Gravidez , Estudos Prospectivos , Reprodutibilidade dos Testes , Ultrassonografia Pré-Natal/métodos , Ultrassonografia Pré-Natal/normas
6.
Appl Environ Microbiol ; 87(19): e0097221, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34288700

RESUMO

Permafrost microbes may be metabolically active in microscopic layers of liquid brines, even in ancient soil. Metagenomics can help discern whether permafrost microbes show adaptations to this environment. Thirty-three metagenome-assembled genomes (MAGs) were obtained from six depths (3.5 m to 20 m) of freshly cored permafrost from the Siberian Kolyma-Indigirka Lowland region. These soils have been continuously frozen for ∼20,000 to 1,000,000 years. Eight of these MAGs were ≥80% complete with <10% contamination and were taxonomically identified as Aminicenantes, Atribacteria, Chloroflexi, and Actinobacteria within bacteria and Thermoprofundales within archaea. MAGs from these taxa have been obtained previously from nonpermafrost environments and have been suggested to show adaptations to long-term energy starvation, but they have never been explored in ancient permafrost. The permafrost MAGs had greater proportions in the Clusters of Orthologous Groups (COGs) categories of energy production and conversion and carbohydrate transport and metabolism than did their nonpermafrost counterparts. They also contained genes for trehalose synthesis, thymine metabolism, mevalonate biosynthesis, and cellulose degradation, which were less prevalent in nonpermafrost genomes. Many of these genes are involved in membrane stabilization and osmotic stress responses, consistent with adaptation to the anoxic, high-ionic-strength, cold environments of permafrost brine films. Our results suggest that this ancient permafrost contains DNA of high enough quality to assemble MAGs from microorganisms with adaptations to survive long-term freezing in this extreme environment. IMPORTANCE Permafrost around the world is thawing rapidly. Many scientists from a variety of disciplines have shown the importance of understanding what will happen to our ecosystem, commerce, and climate when permafrost thaws. The fate of permafrost microorganisms is connected to these predicted rapid environmental changes. Studying ancient permafrost with culture-independent techniques can give a glimpse into how these microorganisms function under these extreme low-temperature and low-energy conditions. This will facilitate understanding how they will change with the environment. This study presents genomic data from this unique environment ∼20,000 to 1,000,000 years of age.


Assuntos
Metagenoma , Pergelissolo/microbiologia , Adaptação Fisiológica , Sibéria
7.
Appl Environ Microbiol ; 86(19)2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32709727

RESUMO

Global marine sediments harbor a large and highly diverse microbial biosphere, but the mechanism by which this biosphere is established during sediment burial is largely unknown. During burial in marine sediments, concentrations of easily metabolized organic compounds and total microbial cell abundance decrease. However, it is unknown whether some microbial clades increase with depth. We show total population increases in 38 microbial families over 3 cm of sediment depth in the upper 7.5 cm of White Oak River (WOR) estuary sediments. Clades that increased with depth were more often associated with one or more of the following: anaerobes, uncultured, or common in deep marine sediments relative to those that decreased. Maximum doubling times (in situ steady-state growth rates could be faster to balance cell decay) were estimated as 2 to 25 years by combining sedimentation rate with either quantitative PCR (qPCR) or the product of the fraction read abundance of 16S rRNA genes and total cell counts (FRAxC). Doubling times were within an order of magnitude of each other in two adjacent cores, as well as in two laboratory enrichments of Cape Lookout Bight (CLB), NC, sediments (average difference of 28% ± 19%). qPCR and FRAxC in sediment cores and laboratory enrichments produced similar doubling times for key deep subsurface uncultured clades Bathyarchaeota (8.7 ± 1.9 years) and Thermoprofundales/MBG-D (4.1 ± 0.7 years). We conclude that common deep subsurface microbial clades experience a narrow zone of growth in shallow sediments, offering an opportunity for selection of long-term subsistence traits after resuspension events.IMPORTANCE Many studies show that the uncultured microbes that dominate global marine sediments do not actually increase in population size as they are buried in marine sediments; rather, they exist in a sort of prolonged torpor for thousands of years. This is because, although studies have shown biomass turnover in these clades, no evidence has ever been found that deeper sediments have larger populations for specific clades than shallower layers. We discovered that they actually do increase population sizes during burial, but only in the upper few centimeters. This suggests that marine sediments may be a vast repository of mostly nongrowing microbes with a thin and relatively rapid area of cell abundance increase in the upper 10 cm, offering a chance for subsurface organisms to undergo natural selection.


Assuntos
Archaea/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Sedimentos Geológicos/microbiologia , Microbiota , Rios/microbiologia , Anaerobiose , North Carolina , RNA Arqueal/análise , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Análise de Sequência de RNA
8.
Appl Environ Microbiol ; 85(15)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31152014

RESUMO

The prevalence of microbial life in permafrost up to several million years (Ma) old has been well documented. However, the long-term survivability, evolution, and metabolic activity of the entombed microbes over this time span remain underexplored. We integrated aspartic acid (Asp) racemization assays with metagenomic sequencing to characterize the microbial activity, phylogenetic diversity, and metabolic functions of indigenous microbial communities across a ∼0.01- to 1.1-Ma chronosequence of continuously frozen permafrost from northeastern Siberia. Although Asp in the older bulk sediments (0.8 to 1.1 Ma) underwent severe racemization relative to that in the youngest sediment (∼0.01 Ma), the much lower d-Asp/l-Asp ratio (0.05 to 0.14) in the separated cells from all samples suggested that indigenous microbial communities were viable and metabolically active in ancient permafrost up to 1.1 Ma. The microbial community in the youngest sediment was the most diverse and was dominated by the phyla Actinobacteria and Proteobacteria In contrast, microbial diversity decreased dramatically in the older sediments, and anaerobic, spore-forming bacteria within Firmicutes became overwhelmingly dominant. In addition to the enrichment of sporulation-related genes, functional genes involved in anaerobic metabolic pathways such as fermentation, sulfate reduction, and methanogenesis were more abundant in the older sediments. Taken together, the predominance of spore-forming bacteria and associated anaerobic metabolism in the older sediments suggest that a subset of the original indigenous microbial community entrapped in the permafrost survived burial over geological time.IMPORTANCE Understanding the long-term survivability and associated metabolic traits of microorganisms in ancient permafrost frozen millions of years ago provides a unique window into the burial and preservation processes experienced in general by subsurface microorganisms in sedimentary deposits because of permafrost's hydrological isolation and exceptional DNA preservation. We employed aspartic acid racemization modeling and metagenomics to determine which microbial communities were metabolically active in the 1.1-Ma permafrost from northeastern Siberia. The simultaneous sequencing of extracellular and intracellular genomic DNA provided insight into the metabolic potential distinguishing extinct from extant microorganisms under frozen conditions over this time interval. This in-depth metagenomic sequencing advances our understanding of the microbial diversity and metabolic functions of extant microbiomes from early Pleistocene permafrost. Therefore, these findings extend our knowledge of the survivability of microbes in permafrost from 33,000 years to 1.1 Ma.


Assuntos
Bactérias Anaeróbias/metabolismo , Sedimentos Geológicos/microbiologia , Microbiota , Pergelissolo/microbiologia , Filogenia , Sibéria
9.
Appl Environ Microbiol ; 85(4)2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30504213

RESUMO

Globally, marine sediments are a vast repository of organic matter, which is degraded through various microbial pathways, including polymer hydrolysis and monomer fermentation. The sources, abundances, and quality (i.e., labile or recalcitrant) of the organic matter and the composition of the microbial assemblages vary between sediments. Here, we examine new and previously published sediment metagenomes from the Baltic Sea and the nearby Kattegat region to determine connections between geochemistry and the community potential to degrade organic carbon. Diverse organic matter hydrolysis encoding genes were present in sediments between 0.25 and 67 meters below seafloor and were in higher relative abundances in those sediments that contained more organic matter. New analysis of previously published metatranscriptomes demonstrated that many of these genes were transcribed in two organic-rich Holocene sediments. Some of the variation in deduced pathways in the metagenomes correlated with carbon content and depositional conditions. Fermentation-related genes were found in all samples and encoded multiple fermentation pathways. Notably, genes involved in alcohol metabolism were amongst the most abundant of these genes, indicating that this is an important but underappreciated aspect of sediment carbon cycling. This study is a step towards a more complete understanding of microbial food webs and the impacts of depositional facies on present sedimentary microbial communities.IMPORTANCE Sediments sequester organic matter over geologic time scales and impact global climate regulation. Microbial communities in marine sediments drive organic matter degradation, but the factors controlling their assemblages and activities, which in turn impact their role in organic matter degradation, are not well understood. Hence, determining the role of microbial communities in carbon cycling in various sediment types is necessary for predicting future sediment carbon cycling. We examined microbial communities in Baltic Sea sediments, which were deposited across various climatic and geographical regimes to determine the relationship between microbial potential for breakdown of organic matter and abiotic factors, including geochemistry and sediment lithology. The findings from this study will contribute to our understanding of carbon cycling in the deep biosphere and how microbial communities live in deeply buried environments.


Assuntos
Ciclo do Carbono , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Microbiota/fisiologia , Água do Mar/química , Água do Mar/microbiologia , Biodegradação Ambiental , Metabolismo dos Carboidratos , Carbono/metabolismo , Ecologia , Ácidos Graxos Voláteis/análise , Fermentação , Cadeia Alimentar , Processos Heterotróficos , Redes e Vias Metabólicas/genética , Metagenoma , Microbiota/genética , Análise Multivariada , Fases de Leitura Aberta/genética
10.
Nature ; 496(7444): 215-8, 2013 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-23535597

RESUMO

Half of the microbial cells in the Earth's oceans are found in sediments. Many of these cells are members of the Archaea, single-celled prokaryotes in a domain of life separate from Bacteria and Eukaryota. However, most of these archaea lack cultured representatives, leaving their physiologies and placement on the tree of life uncertain. Here we show that the uncultured miscellaneous crenarchaeotal group (MCG) and marine benthic group-D (MBG-D) are among the most numerous archaea in the marine sub-sea floor. Single-cell genomic sequencing of one cell of MCG and three cells of MBG-D indicated that they form new branches basal to the archaeal phyla Thaumarchaeota and Aigarchaeota, for MCG, and the order Thermoplasmatales, for MBG-D. All four cells encoded extracellular protein-degrading enzymes such as gingipain and clostripain that are known to be effective in environments chemically similar to marine sediments. Furthermore, we found these two types of peptidase to be abundant and active in marine sediments, indicating that uncultured archaea may have a previously undiscovered role in protein remineralization in anoxic marine sediments.


Assuntos
Archaea/metabolismo , Sedimentos Geológicos/microbiologia , Peptídeo Hidrolases/metabolismo , Adesinas Bacterianas/metabolismo , Archaea/classificação , Archaea/enzimologia , Archaea/genética , Cisteína Endopeptidases/metabolismo , Sedimentos Geológicos/química , Cisteína Endopeptidases Gingipaínas , Biologia Marinha , Dados de Sequência Molecular , Filogenia , Proteólise , RNA Ribossômico 16S/genética , Análise de Célula Única
12.
Appl Environ Microbiol ; 84(1)2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29054869

RESUMO

The difficulty involved in quantifying biogeochemically significant microbes in marine sediments limits our ability to assess interspecific interactions, population turnover times, and niches of uncultured taxa. We incubated surface sediments from Cape Lookout Bight, North Carolina, USA, anoxically at 21°C for 122 days. Sulfate decreased until day 68, after which methane increased, with hydrogen concentrations consistent with the predicted values of an electron donor exerting thermodynamic control. We measured turnover times using two relative quantification methods, quantitative PCR (qPCR) and the product of 16S gene read abundance and total cell abundance (FRAxC, which stands for "fraction of read abundance times cells"), to estimate the population turnover rates of uncultured clades. Most 16S rRNA reads were from deeply branching uncultured groups, and ∼98% of 16S rRNA genes did not abruptly shift in relative abundance when sulfate reduction gave way to methanogenesis. Uncultured Methanomicrobiales and Methanosarcinales increased at the onset of methanogenesis with population turnover times estimated from qPCR at 9.7 ± 3.9 and 12.6 ± 4.1 days, respectively. These were consistent with FRAxC turnover times of 9.4 ± 5.8 and 9.2 ± 3.5 days, respectively. Uncultured Syntrophaceae, which are possibly fermentative syntrophs of methanogens, and uncultured Kazan-3A-21 archaea also increased at the onset of methanogenesis, with FRAxC turnover times of 14.7 ± 6.9 and 10.6 ± 3.6 days. Kazan-3A-21 may therefore either perform methanogenesis or form a fermentative syntrophy with methanogens. Three genera of sulfate-reducing bacteria, Desulfovibrio, Desulfobacter, and Desulfobacterium, increased in the first 19 days before declining rapidly during sulfate reduction. We conclude that population turnover times on the order of days can be measured robustly in organic-rich marine sediment, and the transition from sulfate-reducing to methanogenic conditions stimulates growth only in a few clades directly involved in methanogenesis, rather than in the whole microbial community.IMPORTANCE Many microbes cannot be isolated in pure culture to determine their preferential growth conditions and predict their response to changing environmental conditions. We created a microcosm of marine sediments that allowed us to simulate a diagenetic profile using a temporal analog for depth. This allowed for the observation of the microbial community population dynamics caused by the natural shift from sulfate reduction to methanogenesis. Our research provides evidence for the population dynamics of uncultured microbes as well as the application of a novel method of turnover rate analysis for individual taxa within a mixed incubation, FRAxC, which stands for "fraction of read abundance times cells," which was verified by quantitative PCR. This allows for the calculation of population turnover times for microbes in a natural setting and the identification of uncultured clades involved in geochemical processes.


Assuntos
Archaea/fisiologia , Sedimentos Geológicos/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Água do Mar/microbiologia , Fenômenos Fisiológicos Bacterianos , North Carolina , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
13.
FASEB J ; 29(9): 4071-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26062601

RESUMO

Marine sediments host a large population of diverse, heterotrophic, uncultured microorganisms with unknown physiologies that control carbon flow through organic matter decomposition. Recently, single-cell genomics uncovered new key players in these processes, such as the miscellaneous crenarchaeotal group. These widespread archaea encode putative intra- and extracellular proteases for the degradation of detrital proteins present in sediments. Here, we show that one of these enzymes is a self-compartmentalizing tetrameric aminopeptidase with a preference for cysteine and hydrophobic residues at the N terminus of the hydrolyzed peptide. The ability to perform detailed characterizations of enzymes from native subsurface microorganisms, without requiring that those organisms first be grown in pure culture, holds great promise for understanding key carbon transformations in the environment as well as identifying new enzymes for biomedical and biotechnological applications.


Assuntos
Aminopeptidases/química , Organismos Aquáticos/enzimologia , Archaea/enzimologia , Proteínas Arqueais/química , Aminopeptidases/genética , Organismos Aquáticos/genética , Archaea/genética , Proteínas Arqueais/genética
14.
Environ Microbiol ; 17(10): 3540-56, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24889097

RESUMO

Bacteria of the class Dehalococcoidia (DEH) (phylum Chloroflexi) are widely distributed in the marine subsurface and are especially prevalent in deep marine sediments. Nevertheless, little is known about the specific distributions of DEH subgroups at different sites and depths. This study therefore specifically examined the distributions of DEH through depths of various marine sediment cores by quantitative PCR and pyrosequencing using newly designed DEH 16S rRNA gene targeting primers. Quantification of DEH showed populations may establish in shallow sediments (i.e. upper centimetres), although as low relative proportions of total Bacteria, yet often became more prevalent in deeper sediments. Pyrosequencing revealed pronounced diversity co-exists within single biogeochemical zones, and that clear and sometimes abrupt shifts in relative proportions of DEH subgroups occur with depth. These shifts indicate varying metabolic properties exist among DEH subgroups. The distributional changes in DEH subgroups with depth may be related to a combination of biogeochemical factors including the availability of electron acceptors such as sulfate, the composition of organic matter and depositional regimes. Collectively, the results suggest DEH exhibit wider metabolic and genomic diversity than previously recognized, and this contributes to their widespread occurrence in the marine subsurface.


Assuntos
Organismos Aquáticos/classificação , Chloroflexi/classificação , Chloroflexi/genética , Primers do DNA/genética , Sedimentos Geológicos/microbiologia , Organismos Aquáticos/genética , Sequência de Bases , Biodiversidade , Chloroflexi/isolamento & purificação , DNA Bacteriano/genética , Genômica , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
16.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38613515

RESUMO

Angus-crossbred steers (n = 400; 369.7 ±â€…7.6 kg) were used to determine the influence of trace mineral (TM) source and chromium propionate (Cr Prop) supplementation on performance, carcass characteristics, and ruminal and plasma variables in finishing steers. Steers were blocked by body weight (BW) and randomly assigned within block to treatments in a 2 × 2 factorial arrangement, with factors being: 1) TM source (STM or HTM) and 2) Cr supplementation (0 or 0.25 mg Cr/kg DM, -Cr or + Cr, respectively). Treatments consisted of the addition of: 1) sulfate TM (STM; 90, 40, and 18 mg/kg DM of Zn, Mn, and Cu, respectively), 2) STM and 0.25 mg Cr/kg DM from Cr Prop, 3) hydroxychloride TM (HTM; 90, 40, and 18 mg/kg DM of Zn, Mn, and Cu, respectively), and 4) HTM and 0.25 mg Cr/kg DM from Cr Prop. Each treatment consisted of 10 replicate pens with 10 steers per pen. Body weights were obtained on consecutive days at the initiation and termination of the 154-d study. Steers were fed a steam-flaked corn-based finishing diet. Ractopamine hydrochloride was fed for the last 31 d of the study. Ruminal fluid and blood samples were obtained from one steer per pen on days 28 and 84 for ruminal volatile fatty acids (VFA) and plasma TM and glucose analysis. Steers were slaughtered at the end of the study and individual carcass data were collected. No Cr × TM source interactions (P = 0.48) were detected. Steers supplemented with HTM had greater (P = 0.04) hot carcass weight (HCW), dressing percentage (DP), longissimus muscle (LM) area, and USDA yield grade (YG), and tended (P = 0.12) to have greater average daily gain (ADG) than those receiving STM. Average daily gain, gain:feed, dressing percentage, and longissimus muscle area were greater (P = 0.04) for + Cr steers compared to-Cr steers. Hot carcass weight tended (P = 0.06) to be greater for + Cr steers. Ruminal acetate concentrations at 28 d were lesser (P = 0.01) for HTM vs. STM steers, and greater (P = 0.04) for + Cr steers compared to-Cr steers. Plasma concentrations of Zn, Cu, and Mn were not affected by TM source or Cr supplementation. Steers supplemented with Cr had greater (P = 0.05) plasma glucose concentrations than-Cr steers at 28 but not at 84 d. Results of this study indicate replacing STM with HTM improved carcass characteristics in finishing steers, and Cr Prop supplementation improved steer performance and carcass characteristics.


Trace minerals (TM) are supplemented to finishing cattle diets to prevent TM deficiencies. Sources of TM differ in their bioavailability and effect on rumen fermentation. Chromium is a TM required in low concentrations to enhance insulin activity. We tested the effect of TM source (hydroxychloride; HTM vs. sulfate; STM) and supplemental Cr propionate (Cr Prop) on performance and carcass characteristics of finishing steers. Providing 0.25 mg of supplemental Cr/kg DM, from Cr Prop, improved gain, feed efficiency, and carcass characteristics in steers. Steers supplemented with HTM tended to gain faster and had improved carcass characteristics of economic importance compared to those supplemented with STM.


Assuntos
Ração Animal , Dieta , Suplementos Nutricionais , Propionatos , Oligoelementos , Animais , Bovinos/fisiologia , Bovinos/crescimento & desenvolvimento , Masculino , Suplementos Nutricionais/análise , Ração Animal/análise , Dieta/veterinária , Oligoelementos/farmacologia , Oligoelementos/administração & dosagem , Propionatos/farmacologia , Propionatos/administração & dosagem , Rúmen/efeitos dos fármacos , Rúmen/metabolismo , Composição Corporal/efeitos dos fármacos , Cromo/farmacologia , Cromo/administração & dosagem , Fenômenos Fisiológicos da Nutrição Animal , Distribuição Aleatória , Carne/análise
17.
bioRxiv ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38559265

RESUMO

The microbiome is a complex community of microorganisms, encompassing prokaryotic (bacterial and archaeal), eukaryotic, and viral entities. This microbial ensemble plays a pivotal role in influencing the health and productivity of diverse ecosystems while shaping the web of life. However, many software suites developed to study microbiomes analyze only the prokaryotic community and provide limited to no support for viruses and microeukaryotes. Previously, we introduced the Viral Eukaryotic Bacterial Archaeal (VEBA) open-source software suite to address this critical gap in microbiome research by extending genome-resolved analysis beyond prokaryotes to encompass the understudied realms of eukaryotes and viruses. Here we present VEBA 2.0 with key updates including a comprehensive clustered microeukaryotic protein database, rapid genome/protein-level clustering, bioprospecting, non-coding/organelle gene modeling, genome-resolved taxonomic/pathway profiling, long-read support, and containerization. We demonstrate VEBA's versatile application through the analysis of diverse case studies including marine water, Siberian permafrost, and white-tailed deer lung tissues with the latter showcasing how to identify integrated viruses. VEBA represents a crucial advancement in microbiome research, offering a powerful and accessible platform that bridges the gap between genomics and biotechnological solutions.

18.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38625060

RESUMO

High-elevation arid regions harbor microbial communities reliant on metabolic niches and flexibility to survive under biologically stressful conditions, including nutrient limitation that necessitates the utilization of atmospheric trace gases as electron donors. Geothermal springs present "oases" of microbial activity, diversity, and abundance by delivering water and substrates, including reduced gases. However, it is unknown whether these springs exhibit a gradient of effects, increasing their impact on trace gas-oxidizers in the surrounding soils. We assessed whether proximity to Polloquere, a high-altitude geothermal spring in an Andean salt flat, alters the diversity and metabolic structure of nearby soil bacterial populations compared to the surrounding cold desert. Recovered DNA and metagenomic analyses indicate that the spring represents an oasis for microbes in this challenging environment, supporting greater biomass with more diverse metabolic functions in proximal soils that declines sharply with radial distance from the spring. Despite the sharp decrease in biomass, potential rates of atmospheric hydrogen (H2) and carbon monoxide (CO) uptake increase away from the spring. Kinetic estimates suggest this activity is due to high-affinity trace gas consumption, likely as a survival strategy for energy/carbon acquisition. These results demonstrate that Polloquere regulates a gradient of diverse microbial communities and metabolisms, culminating in increased activity of trace gas-oxidizers as the influence of the spring yields to that of the regional salt flat environment. This suggests the spring holds local importance within the context of the broader salt flat and potentially represents a model ecosystem for other geothermal systems in high-altitude desert environments.


Assuntos
Bactérias , Clima Desértico , Fontes Termais , Oxirredução , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/isolamento & purificação , Fontes Termais/microbiologia , Monóxido de Carbono/metabolismo , Hidrogênio/metabolismo , Microbiota , Altitude , Solo/química
19.
Syst Appl Microbiol ; 47(6): 126544, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39303414

RESUMO

Arctic soil microbial communities may shift with increasing temperatures and water availability from climate change. We examined temperature and volumetric liquid water content (VWC) in the upper 80 cm of permafrost-affected soil over 2 years (2018-2019) at the Bayelva monitoring station, Ny Ålesund, Svalbard. We show VWC increases with depth, whereas in situ temperature is more stable vertically, ranging from -5°C to 5 °C seasonally. Prokaryotic metagenome-assembled genomes (MAGs) were obtained at 2-4 cm vertical resolution collected while frozen in April 2018 and at 10 cm vertical resolution collected while thawed in September 2019. The most abundant MAGs were Acidobacteriota, Actinomycetota, and Chloroflexota. Actinomycetota and Chloroflexota increase with depth, while Acidobacteriota classes Thermoanaerobaculia Gp7-AA8, Blastocatellia UBA7656, and Vicinamibacteria Vicinamibacterales are found above 6 cm, below 6 cm, and below 20 cm, respectively. All MAGs have diverse carbon-degrading genes, and Actinomycetota and Chloroflexota have autotrophic genes. Genes encoding ß -glucosidase, N-acetyl-ß-D-glucosaminidase, and xylosidase increase with depth, indicating a greater potential for organic matter degradation with higher VWC. Acidobacteriota dominate the top 6 cm with their classes segregating by depth, whereas Actinomycetota and Chloroflexota dominate below ∼6 cm. This suggests that Acidobacteriota classes adapt to lower VWC at the surface, while Actinomycetota and Chloroflexota persist below 6 cm with higher VWC. This indicates that VWC may be as important as temperature in microbial climate change responses in Arctic mineral soils. Here we describe MAG-based Seqcode type species in the Acidobacteriota, Onstottus arcticum, Onstottus frigus, and Gilichinskyi gelida and in the Actinobacteriota, Mayfieldus profundus.

20.
Appl Environ Microbiol ; 79(24): 7790-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24096423

RESUMO

There is no universally accepted method to quantify bacteria and archaea in seawater and marine sediments, and different methods have produced conflicting results with the same samples. To identify best practices, we compiled data from 65 studies, plus our own measurements, in which bacteria and archaea were quantified with fluorescent in situ hybridization (FISH), catalyzed reporter deposition FISH (CARD-FISH), polyribonucleotide FISH, or quantitative PCR (qPCR). To estimate efficiency, we defined "yield" to be the sum of bacteria and archaea counted by these techniques divided by the total number of cells. In seawater, the yield was high (median, 71%) and was similar for FISH, CARD-FISH, and polyribonucleotide FISH. In sediments, only measurements by CARD-FISH in which archaeal cells were permeabilized with proteinase K showed high yields (median, 84%). Therefore, the majority of cells in both environments appear to be alive, since they contain intact ribosomes. In sediments, the sum of bacterial and archaeal 16S rRNA gene qPCR counts was not closely related to cell counts, even after accounting for variations in copy numbers per genome. However, qPCR measurements were precise relative to other qPCR measurements made on the same samples. qPCR is therefore a reliable relative quantification method. Inconsistent results for the relative abundance of bacteria versus archaea in deep subsurface sediments were resolved by the removal of CARD-FISH measurements in which lysozyme was used to permeabilize archaeal cells and qPCR measurements which used ARCH516 as an archaeal primer or TaqMan probe. Data from best-practice methods showed that archaea and bacteria decreased as the depth in seawater and marine sediments increased, although archaea decreased more slowly.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Sedimentos Geológicos/microbiologia , Técnicas Microbiológicas/métodos
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