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1.
Gastroenterology ; 165(1): 104-120, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36933623

RESUMO

BACKGROUND & AIMS: Dysbiosis of gut microbiota is linked to the development of colorectal cancer (CRC). However, microbiota-based stratification of CRC tissue and how this relates to clinicomolecular characteristics and prognosis remains to be clarified. METHODS: Tumor and normal mucosa from 423 patients with stage I to IV CRC were profiled by bacterial 16S rRNA gene sequencing. Tumors were characterized for microsatellite instability (MSI), CpG island methylator phenotype (CIMP), APC, BRAF, KRAS, PIK3CA, FBXW7, SMAD4, and TP53 mutations, subsets for chromosome instability (CIN), mutation signatures, and consensus molecular subtypes (CMS). Microbial clusters were validated in an independent cohort of 293 stage II/III tumors. RESULTS: Tumors reproducibly stratified into 3 oncomicrobial community subtypes (OCSs) with distinguishing features: OCS1 (Fusobacterium/oral pathogens, proteolytic, 21%), right-sided, high-grade, MSI-high, CIMP-positive, CMS1, BRAF V600E, and FBXW7 mutated; OCS2 (Firmicutes/Bacteroidetes, saccharolytic, 44%), and OCS3 (Escherichia/Pseudescherichia/Shigella, fatty acid ß-oxidation, 35%) both left-sided and exhibiting CIN. OCS1 was associated with MSI-related mutation signatures (SBS15, SBS20, ID2, and ID7) and OCS2 and OCS3 with SBS18 related to damage by reactive oxygen species. Among stage II/III patients, OCS1 and OCS3 both had poorer overall survival compared with OCS2 for microsatellite stable tumors (multivariate hazard ratio [HR], 1.85; 95% confidence interval [CI], 1.15-2.99; P = .012; and HR, 1.52; 95% CI 1.01-2.29; P = .044, respectively) and left-sided tumors (multivariate HR, 2.66; 95% CI, 1.45-4.86; P = .002; and HR, 1.76; 95% CI, 1.03-3.02; P = .039, respectively). CONCLUSIONS: OCS classification stratified CRCs into 3 distinct subgroups with different clinicomolecular features and outcomes. Our findings provide a framework for a microbiota-based stratification of CRC to refine prognostication and to inform the development of microbiota-targeted interventions.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas B-raf , Humanos , Prognóstico , Proteína 7 com Repetições F-Box-WD/genética , Proteínas Proto-Oncogênicas B-raf/genética , RNA Ribossômico 16S , Metilação de DNA , Mutação , Instabilidade de Microssatélites , Instabilidade Cromossômica , Fenótipo , Neoplasias Colorretais/patologia , Ilhas de CpG
2.
Environ Microbiol ; 24(9): 4065-4078, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35437913

RESUMO

The production of methane as an end-product of organic matter degradation in the absence of other terminal electron acceptors is common, and has often been studied in environments such as animal guts, soils and wetlands due to its potency as a greenhouse gas. To date, however, the study of the biogeographic distribution of methanogens across coal seam environments has been minimal. Here, we show that coal seams are host to a diverse range of methanogens, which are distinctive to each geological basin. Based on comparisons to close relatives from other methanogenic environments, the dominant methanogenic pathway in these basins is hydrogenotrophic, with acetoclastic being a second major pathway in the Surat Basin. Finally, mcrA and 16S rRNA gene primer biases were predominantly seen to affect the detection of Methanocellales, Methanomicrobiales and Methanosarcinales taxa in this study. Subsurface coal methanogenic community distributions and pathways presented here provide insights into important metabolites and bacterial partners for in situ coal biodegradation.


Assuntos
Euryarchaeota , Gases de Efeito Estufa , Animais , Archaea/metabolismo , Carvão Mineral/microbiologia , Euryarchaeota/genética , Gases de Efeito Estufa/metabolismo , Metano/metabolismo , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Solo
3.
Microb Ecol ; 84(3): 780-793, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34686899

RESUMO

The global trend of transiting to more renewable energy sources requires transition fuels, such as coal seam gas, to supplement and secure energy needs. In order to optimise strategies and technologies for enhancing gas production, an understanding of the fundamental microbial processes and interactions would be advantageous. Models have recently begun mapping the microbial roles and interactions in coal seam environments, from direct coal degradation to methanogenesis. This study seeks to expand those models by observing community compositional shifts in the presence of differing organic matter by conducting 16S rRNA microbial surveys using formation water from the Surat and Sydney Basins grown on varying types of organic matter (black and brown coal, oil shale, humic acid, and lignin). A total of 135 microbes were observed to become enriched in the presence of added organic matter in comparison to carbon-free treatments. These surveys allowed detailed analysis of microbial compositions in order to extrapolate which taxa favour growth in the presence of differing organic matter. This study has experimentally demonstrated shifts in the microbial community composition due to differing carbon sources and, for the first time, generated a conceptual model to map putative degradation pathways regarding subsurface microbial consortia.


Assuntos
Carvão Mineral , Microbiota , RNA Ribossômico 16S/genética , Metano/metabolismo , Consórcios Microbianos/genética
4.
J Hand Surg Am ; 47(8): 752-761.e1, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34509312

RESUMO

PURPOSE: Carpal tunnel syndrome is a common condition, with well-defined diagnostic and treatment guidelines. Despite these guidelines, continued variation in care exists, with providers variably using diagnostic tests and nonsurgical treatment modalities prior to surgery. The purpose of this study was to evaluate the variation and cost associated with the diagnosis and nonsurgical treatment of patients prior to undergoing carpal tunnel release. METHODS: We queried the Truven MarketScan database to identify patients who underwent carpal tunnel release from 2010 to 2017. Patients were identified using common current procedural terminology codes and included if they were enrolled in the database for a minimum of 12 months prior to surgery to allow all preoperative data to be captured. All associated current procedural terminology codes during the 1-year preoperative period were refined to codes related to median neuropathy and categorized as office visits, diagnostic imaging (x-ray, ultrasound, and magnetic resonance imaging), electrodiagnostic testing, injections, occupational or physical therapy, durable medical equipment, and preoperative laboratory tests. RESULTS: In total, 378,381 patients were included in the study. A per-patient average cost of $858.74 was spent on preoperative workup and nonsurgical treatment. Electrodiagnostic testing represented 44.6% of the cost, and office visits represented 31.9%. Regarding nonsurgical treatment, 16.1% of the patients received an injection during the 1-year preoperative period, 26.8% received a medical brace, and 6.6% used physical therapy. When analyzed based on age group, the per-patient average cost for patients aged 70 years or older was significantly less than those younger than 70 years ($723.92 vs $878.76). CONCLUSIONS: Despite robust clinical practice guidelines and high volumes, significant variation in presurgical care exists. These data are useful to begin to critically analyze the causes of variation in the diagnosis and treatment of carpal tunnel syndrome and move toward a more effective, efficient, and informed treatment strategy. TYPE OF STUDY/LEVEL OF EVIDENCE: Economic/decision analysis II.


Assuntos
Síndrome do Túnel Carpal , Síndrome do Túnel Carpal/diagnóstico , Síndrome do Túnel Carpal/cirurgia , Bases de Dados Factuais , Descompressão Cirúrgica/métodos , Humanos , Modalidades de Fisioterapia , Estudos Retrospectivos
5.
Microb Ecol ; 80(1): 34-46, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31828390

RESUMO

Diverse microbial communities living in subsurface coal seams are responsible for important geochemical processes including the movement of carbon between the geosphere, biosphere and atmosphere. Microbial conversion of the organic matter in coal to methane involves a complex assemblage of bacteria and archaea working in syntrophic relationships. Despite the importance and value of this microbial process, very few of the microbial taxa have defined metabolic or ecological roles in these environments. Additionally, the genomic features mediating life in this chemically reduced, energy poor, deep subsurface environment are not well characterised. Here we describe the isolation and genomic and catabolic characterisation of three alphaproteobacterial Stappia indica species from three coal basins across Australia. S. indica genomes from coal seams were compared with those from closely related S. indica isolated from diverse surface waters, revealing a coal seam-specific suite of genes associated with life in the subsurface. These genes are linked to processes including viral defence, secondary metabolite production, polyamine metabolism, polypeptide uptake membrane transporters and putative energy neutral pressure-dependent CO2 fixation. This indicates that subsurface Stappia have diverse metabolisms for biomass recycling and pressure-dependent CO2 fixation and require a suite of defensive and competitive strategies relative to their surface-dwelling relatives.


Assuntos
Ciclo do Carbono , Água Doce/microbiologia , Genoma Bacteriano , Sedimentos Geológicos/microbiologia , Rhodobacteraceae/fisiologia , Biomassa , Carvão Mineral , Mineração , New South Wales , Queensland , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Especificidade da Espécie
6.
Microb Ecol ; 75(4): 970-984, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29128951

RESUMO

Elevated uranium dose (4 g kg-1) causes a shift in billabong sediment communities that result in the enrichment of five bacterial species. These taxa include Geobacter, Geothrix and Dyella species, as well as a novel-potentially predatory-Bacteroidetes species, and a new member of class Anaerolineae (Chloroflexi). Additionally, a population of methanogenic Methanocella species was also identified. Genomic reconstruction and metabolic examination of these taxa reveal a host of divergent life strategies and putative niche partitioning. Resistance-nodulation-division heavy metal efflux (RND-HME) transporters are implicated as potential uranium tolerance strategies among the bacterial taxa. Potential interactions, uranium tolerance and ecologically relevant catabolism are presented in a conceptual model of life in this environment.


Assuntos
Bactérias/genética , Genômica , Sedimentos Geológicos/microbiologia , Metagenoma , Urânio/metabolismo , Bactérias/classificação , Bactérias/enzimologia , Proteínas de Bactérias/genética , Metabolismo dos Carboidratos , DNA Bacteriano/genética , Tolerância a Medicamentos , Ecologia , Genes Bacterianos/genética , Geobacter/classificação , Geobacter/genética , Anotação de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
7.
Mycorrhiza ; 28(4): 379-389, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29700603

RESUMO

This study describes a novel ericoid mycorrhizal fungus (ErMF), Gamarada debralockiae Midgley and Tran-Dinh gen. nov. sp. nov. Additionally, catabolism was explored from a genomic perspective. The nuclear and mitochondrial genomes of G. debralockiae were sequenced. Morphological characteristics were assessed on various media. Catabolic genes of G. debralockiae were explored using SignalP and dbCAN. Phylogenetic comparisons were undertaken using Phylogeny.fr. The 58.5-Mbp draft genome of G. debralockiae contained 17,075 putative genes. The complete mitochondrial genome was 28,168 bp in length. In culture, G. debralockiae produces slow-growing non-sporulating colonies. Gamarada debralockiae has many putative secreted catabolic enzymes. Phylogeny indicated G. debralockiae was distinct from known ascomycetous ErMF: Pezoloma ericae, Meliniomyces spp., Oidiodendron spp., and Cairneyella variabilis. It is closely related to many undescribed plant root-associated fungi and its nearest described relative is Hyphodiscus brevicollaris. Gamarada debralockiae has been recovered from virtually all Australian ericoid mycorrhizal studies and biogeographic data suggests the taxon is widespread in Australia. Gamarada debralockiae has similar catabolic potential to C. variabilis and co-occurs with C. variabilis at Australian sites. Plants that host multiple ErMF may benefit from subtle differences in catabolism that improve access to nitrogen and phosphorus from within recalcitrant organic matter.


Assuntos
Ascomicetos/classificação , Ericaceae/microbiologia , Genoma Fúngico , Micorrizas/classificação , Ascomicetos/fisiologia , Sequência de Bases , DNA Intergênico/genética , Micorrizas/fisiologia , New South Wales , Filogenia
8.
Environ Microbiol ; 19(8): 3323-3341, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28631400

RESUMO

Located in the Northern Territory of Australia, Ranger uranium mine is directly adjacent to the UNESCO World Heritage listed Kakadu National Park, with rehabilitation targets needed to ensure the site can be incorporated into the park following the mine's closure in 2026. This study aimed to understand the impact of uranium concentration on microbial communities, in order to identify and describe potential breakpoints in microbial ecosystem services. This is the first study to report in situ deployment of uranium-spiked sediments along a concentration gradient (0-4000 mg U kg-1 ), with the study design maximising the advantages of both field surveys and laboratory manipulative studies. Changes to microbial communities were characterised through the use of amplicon and shotgun metagenomic next-generation sequencing. Significant changes to taxonomic and functional community assembly occurred at a concentration of 1500 mg U kg-1 sediment and above. At uranium concentrations of ≥ 1500 mg U kg-1 , genes associated with methanogenic consortia and processes increased in relative abundance, while numerous significant changes were also seen in the relative abundances of genes involved in nitrogen cycling. Such alterations in carbon and nitrogen cycling pathways suggest that taxonomic and functional changes to microbial communities may result in changes in ecosystem processes and resilience.


Assuntos
Bactérias/genética , Ciclo do Carbono/genética , Sedimentos Geológicos/química , Consórcios Microbianos/efeitos dos fármacos , Ciclo do Nitrogênio/genética , Transportadores de Cassetes de Ligação de ATP/genética , Austrália , Bactérias/classificação , Bactérias/metabolismo , Sequência de Bases , Carbono/metabolismo , Ecossistema , Sedimentos Geológicos/microbiologia , Metagenômica , Metano/metabolismo , Mineração , Nitrogênio/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Urânio/metabolismo , Urânio/farmacologia
9.
Mycorrhiza ; 27(6): 587-594, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28315064

RESUMO

The prominent ericoid mycorrhizal fungus, Pezoloma ericae, has not been found in Australia to date. In the present study, internal transcribed spacer (ITS) data from the Biomes of Australia Soil Environments (BASE) was searched for evidence of P. ericae and other known ericoid mycorrhizal and root-associated taxa. ITS sequences with high identity to P. ericae, Meliniomyces bicolor, Meliniomyces variabilis, Cairneyella sp. 2, Cadophora finlandica and Woollsia mycorrhizal fungus VI were identified and their distribution in Australia visualised. This is the first evidence that P. ericae, M. bicolor and M. variabilis very likely occur on the Australian continent and provides a set of locations from which to seek isolates for further characterisation. The presence of P. ericae in South America, South Africa, and now Australia suggests a broad and ancient Gondwanan distribution for this well-studied species.


Assuntos
Ecossistema , Ericaceae/microbiologia , Micorrizas/classificação , Raízes de Plantas/microbiologia , Microbiologia do Solo , Austrália , Filogeografia , Solo
10.
Appl Environ Microbiol ; 82(22): 6507-6517, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27590809

RESUMO

We report the isolation and characterization of three new cytochrome P450 monooxygenases: CYP101J2, CYP101J3, and CYP101J4. These P450s were derived from Sphingobium yanoikuyae B2, a strain that was isolated from activated sludge based on its ability to fully mineralize 1,8-cineole. Genome sequencing of this strain in combination with purification of native 1,8-cineole-binding proteins enabled identification of 1,8-cineole-binding P450s. The P450 enzymes were cloned, heterologously expressed (N-terminally His6 tagged) in Escherichia coli BL21(DE3), purified, and spectroscopically characterized. Recombinant whole-cell biotransformation in E. coli demonstrated that all three P450s hydroxylate 1,8-cineole using electron transport partners from E. coli to yield a product putatively identified as (1S)-2α-hydroxy-1,8-cineole or (1R)-6α-hydroxy-1,8-cineole. The new P450s belong to the CYP101 family and share 47% and 44% identity with other 1,8-cineole-hydroxylating members found in Novosphingobium aromaticivorans and Pseudomonas putida Compared to P450cin (CYP176A1), a 1,8-cineole-hydroxylating P450 from Citrobacter braakii, these enzymes share less than 30% amino acid sequence identity and hydroxylate 1,8-cineole in a different orientation. Expansion of the enzyme toolbox for modification of 1,8-cineole creates a starting point for use of hydroxylated derivatives in a range of industrial applications. IMPORTANCE: CYP101J2, CYP101J3, and CYP101J4 are cytochrome P450 monooxygenases from S. yanoikuyae B2 that hydroxylate the monoterpenoid 1,8-cineole. These enzymes not only play an important role in microbial degradation of this plant-based chemical but also provide an interesting route to synthesize oxygenated 1,8-cineole derivatives for applications as natural flavor and fragrance precursors or incorporation into polymers. The P450 cytochromes also provide an interesting basis from which to compare other enzymes with a similar function and expand the CYP101 family. This could eventually provide enough bacterial parental enzymes with similar amino acid sequences to enable in vitro evolution via DNA shuffling.


Assuntos
Cânfora 5-Mono-Oxigenase/isolamento & purificação , Cânfora 5-Mono-Oxigenase/metabolismo , Cicloexanóis/metabolismo , Monoterpenos/metabolismo , Esgotos/microbiologia , Sphingomonadaceae/enzimologia , Biotransformação , Cânfora 5-Mono-Oxigenase/classificação , Cânfora 5-Mono-Oxigenase/genética , Citrobacter/enzimologia , Citrobacter/genética , Transporte de Elétrons , Escherichia coli/genética , Eucaliptol , Genoma Bacteriano , Hidroxilação , Microbiologia Industrial , Ligação Proteica , Pseudomonas putida/enzimologia , Pseudomonas putida/genética , Proteínas Recombinantes/metabolismo , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Sphingomonadaceae/metabolismo
11.
Mycologia ; 108(1): 1-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26553774

RESUMO

Fungi are key organisms in many ecological processes and communities. Rapid and low cost surveys of the fungal members of a community can be undertaken by isolating and sequencing a taxonomically informative genomic region, such as the ITS (internal transcribed spacer), from DNA extracted from a metagenomic sample, and then classifying these sequences to determine which organisms are present. This paper announces the availability of the Warcup ITS training set and shows how it can be used with the Ribosomal Database Project (RDP) Bayesian Classifier to rapidly and accurately identify fungi using ITS sequences. The classifications can be down to species level and use conventional literature-based mycological nomenclature and taxonomic assignments.


Assuntos
Fungos/classificação , Teorema de Bayes , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Conjuntos de Dados como Assunto , Fungos/genética , Reprodutibilidade dos Testes , Análise de Sequência de DNA
12.
Mycorrhiza ; 26(4): 345-52, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26861481

RESUMO

This paper describes a novel species of ericoid mycorrhizal fungus from Australia, Cairneyella variabilis, Midgley and Tran-Dinh, gen. nov. sp. nov. The genome of C. variabilis was sequenced and a draft genome assembled. The draft genome of C. variabilis is 52.4 Mbp in length, and to our knowledge, this is the first study to present a genome of an ericoid mycorrhizal fungus from the southern hemisphere. Using the SignalP and dbCAN bioinformatic pipelines, a study of the catabolic potential of C. variabilis was undertaken and showed genes for an array of degradative enzymes, most of which appear to be secreted from the hyphae, to access a suite of different carbon sources. Isolates of C. variabilis have been previously shown to utilise cellulose, carboxymethyl cellulose (CMC), cellobiose, xylan, pectin, starch and tannic acid for growth, and in the current study, putative enzymes for these processes were revealed. These enzymes likely play key roles in nutrient cycling and other edaphic processes in heathland environments. ITS phylogenetic analyses showed C. variabilis to be distinct from the fungi of the "Hymenoscyphus ericae aggregate".


Assuntos
Ascomicetos/isolamento & purificação , Ericaceae/microbiologia , Genoma Fúngico , Micorrizas/isolamento & purificação , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/metabolismo , Austrália , Metabolismo dos Carboidratos , Genômica , Micorrizas/classificação , Micorrizas/genética , Micorrizas/metabolismo , Nitrogênio/metabolismo , Filogenia
13.
Bioinformatics ; 30(19): 2723-32, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24919879

RESUMO

MOTIVATION: Bioinformatics tools, such as assemblers and aligners, are expected to produce more accurate results when given better quality sequence data as their starting point. This expectation has led to the development of stand-alone tools whose sole purpose is to detect and remove sequencing errors. A good error-correcting tool would be a transparent component in a bioinformatics pipeline, simply taking sequence data in any of the standard formats and producing a higher quality version of the same data containing far fewer errors. It should not only be able to correct all of the types of errors found in real sequence data (substitutions, insertions, deletions and uncalled bases), but it has to be both fast enough and scalable enough to be usable on the large datasets being produced by current sequencing technologies, and work on data derived from both haploid and diploid organisms. RESULTS: This article presents Blue, an error-correction algorithm based on k-mer consensus and context. Blue can correct substitution, deletion and insertion errors, as well as uncalled bases. It accepts both FASTQ and FASTA formats, and corrects quality scores for corrected bases. Blue also maintains the pairing of reads, both within a file and between pairs of files, making it compatible with downstream tools that depend on read pairing. Blue is memory efficient, scalable and faster than other published tools, and usable on large sequencing datasets. On the tests undertaken, Blue also proved to be generally more accurate than other published algorithms, resulting in more accurately aligned reads and the assembly of longer contigs containing fewer errors. One significant feature of Blue is that its k-mer consensus table does not have to be derived from the set of reads being corrected. This decoupling makes it possible to correct one dataset, such as small set of 454 mate-pair reads, with the consensus derived from another dataset, such as Illumina reads derived from the same DNA sample. Such cross-correction can greatly improve the quality of small (and expensive) sets of long reads, leading to even better assemblies and higher quality finished genomes. AVAILABILITY AND IMPLEMENTATION: The code for Blue and its related tools are available from http://www.bioinformatics.csiro.au/Blue. These programs are written in C# and run natively under Windows and under Mono on Linux.


Assuntos
Algoritmos , Biologia Computacional/métodos , Análise de Sequência de DNA/métodos , Animais , DNA Bacteriano/análise , Bases de Dados Genéticas , Genoma , Genoma Bacteriano , Genoma Humano , Humanos , Ploidias , Reprodutibilidade dos Testes , Deleção de Sequência , Software
14.
Appl Microbiol Biotechnol ; 99(7): 3155-67, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25586584

RESUMO

Many Bacillus species can produce biosurfactant, although most of the studies on lipopeptide production by this genus have been focused on Bacillus subtilis. Surfactants are broadly used in pharmaceutical, food and petroleum industry, and biological surfactant shows some advantages over the chemical surfactants, such as less toxicity, production from renewable, cheaper feedstocks and development of novel recombinant hyperproducer strains. This study is aimed to unveil the biosurfactant metabolic pathway and chemical composition in Bacillus safensis strain CCMA-560. The whole genome of the CCMA-560 strain was previously sequenced, and with the aid of bioinformatics tools, its biosurfactant metabolic pathway was compared to other pathways of closely related species. Fourier transform infrared (FTIR) and high-resolution TOF mass spectrometry (MS) were used to characterize the biosurfactant molecule. B. safensis CCMA-560 metabolic pathway is similar to other Bacillus species; however, some differences in amino acid incorporation were observed, and chemical analyses corroborated the genetic results. The strain CCMA-560 harbours two genes flanked by srfAC and srfAD not present in other Bacillus spp., which can be involved in the production of the analogue gramicidin. FTIR and MS showed that B. safensis CCMA-560 produces a mixture of at least four lipopeptides with seven amino acids incorporated and a fatty acid chain with 14 carbons, which makes this molecule similar to the biosurfactant of Bacillus pumilus, namely, pumilacidin. This is the first report on the biosurfactant production by B. safensis, encompassing the investigation of the metabolic pathway and chemical characterization of the biosurfactant molecule.


Assuntos
Bacillus/genética , Bacillus/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Bacillus/isolamento & purificação , Espectrometria de Massas/métodos , Redes e Vias Metabólicas , Filogenia , RNA Ribossômico 16S , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Sci Total Environ ; 946: 174101, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38906296

RESUMO

Eukaryotic communities in groundwater may be particularly sensitive to disturbance because they are adapted to stable environmental conditions and often have narrow spatial distributions. Traditional methods for characterising these communities, focussing on groundwater-inhabiting macro- and meiofauna (stygofauna), are challenging because of limited taxonomic knowledge and expertise (particularly in less-explored regions), and the time and expense of morphological identification. The primary objective of this study was to evaluate the vulnerability of eukaryote communities in shallow groundwater to mine water discharge containing elevated concentrations of magnesium (Mg) and sulfate (SO4). The study was undertaken in a shallow sand bed aquifer within a wet-dry tropical setting. The aquifer, featuring a saline mine water gradient primarily composed of elevated Mg and SO4, was sampled from piezometers in the creek channel upstream and downstream of the mine water influence during the dry season when only subsurface water flow was present. Groundwater communities were characterised using both morphological assessments of stygofauna from net samples and environmental DNA (eDNA) targeting the 18S rDNA and COI mtDNA genes. eDNA data revealed significant shifts in community composition in response to mine waters, contrasting with findings from traditional morphological composition data. Changes in communities determined using eDNA data were notably associated with concentrations of SO42-, Mg2+ and Na+, and water levels in the piezometers. This underscores the importance of incorporating molecular approaches in impact assessments, as relying solely on traditional stygofauna sampling methods in similar environments may lead to inaccurate conclusions about the responses of the assemblage to studied impacts.

16.
Orthop Clin North Am ; 55(3): 355-362, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38782507

RESUMO

Fragility fractures as a result of osteoporosis, osteopenia, or vitamin D deficiency are some of the most common injuries encountered in orthopedics and require careful consideration when determining the appropriate management and treatment options. A thorough perioperative evaluation can identify causes of low bone mineral density allowing for initiation of appropriate therapy. Surgical treatment of these fractures can be difficult, and techniques should be employed to ensure stable fixation. It is important to understand the potential pitfalls associated with treatment of fragility fractures to prevent avoidable complications. Postoperative management is key to preventing future injuries in this unique patient population.


Assuntos
Doenças Ósseas Metabólicas , Osteoporose , Deficiência de Vitamina D , Humanos , Deficiência de Vitamina D/complicações , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/prevenção & controle , Osteoporose/complicações , Extremidade Superior/cirurgia , Extremidade Superior/lesões , Fraturas por Osteoporose/cirurgia , Fraturas por Osteoporose/prevenção & controle , Fraturas por Osteoporose/etiologia , Densidade Óssea
17.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230123, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38705177

RESUMO

Arthropods contribute importantly to ecosystem functioning but remain understudied. This undermines the validity of conservation decisions. Modern methods are now making arthropods easier to study, since arthropods can be mass-trapped, mass-identified, and semi-mass-quantified into 'many-row (observation), many-column (species)' datasets, with homogeneous error, high resolution, and copious environmental-covariate information. These 'novel community datasets' let us efficiently generate information on arthropod species distributions, conservation values, uncertainty, and the magnitude and direction of human impacts. We use a DNA-based method (barcode mapping) to produce an arthropod-community dataset from 121 Malaise-trap samples, and combine it with 29 remote-imagery layers using a deep neural net in a joint species distribution model. With this approach, we generate distribution maps for 76 arthropod species across a 225 km2 temperate-zone forested landscape. We combine the maps to visualize the fine-scale spatial distributions of species richness, community composition, and site irreplaceability. Old-growth forests show distinct community composition and higher species richness, and stream courses have the highest site-irreplaceability values. With this 'sideways biodiversity modelling' method, we demonstrate the feasibility of biodiversity mapping at sufficient spatial resolution to inform local management choices, while also being efficient enough to scale up to thousands of square kilometres. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Assuntos
Artrópodes , Biodiversidade , DNA Ambiental , Tecnologia de Sensoriamento Remoto , Artrópodes/classificação , Animais , DNA Ambiental/análise , Tecnologia de Sensoriamento Remoto/métodos , Florestas , Distribuição Animal , Código de Barras de DNA Taxonômico/métodos
18.
mBio ; 15(3): e0173523, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38345372

RESUMO

Biogenic methane in subsurface coal seam environments is produced by diverse consortia of microbes. Although this methane is useful for global energy security, it remains unclear which microbes can liberate carbon from the coal. Most of this carbon is relatively resistant to biodegradation, as it is contained within aromatic rings. Thus, to explore for coal-degrading taxa in the subsurface, this study reconstructed relevant metagenome-assembled genomes (MAGs) from coal seams by using a key genomic marker for the anaerobic degradation of monoaromatic compounds as a guide: the benzoyl-CoA reductase gene (bcrABCD). Three MAGs were identified with this genetic potential. The first represented a novel taxon from the Krumholzibacteriota phylum, which this study is the first to describe. This Krumholzibacteriota MAG contained a full set of genes for benzoyl-CoA dearomatization, in addition to other genes for anaerobic catabolism of monoaromatics. Analysis of Krumholzibacteriota MAGs from other environments revealed that this genetic potential may be common, and thus, Krumholzibacteriota may be important organisms for the liberation of recalcitrant carbon in a broad range of environments. Moreover, the assembly and characterization of two Syntrophorhabdus aromaticivorans MAGs from different continents and a Syntrophaceae sp. MAG implicate the Deltaproteobacteria class in coal seam monoaromatic degradation. Each of these taxa are potential rate-limiting organisms for subsurface coal-to-methane biodegradation. Their description here provides some understanding of their function within the coal seam microbiome and will help inform future efforts in coal bed methane stimulation, anoxic bioremediation of organic pollutants, and assessments of anoxic, subsurface carbon cycling and emissions.IMPORTANCESubsurface coal seams are highly anoxic, oligotrophic environments, where the main source of carbon is "locked away" within aromatic rings. Despite these challenges, many coal seams accumulate biogenic methane, implying that the coal seam microbiome is "unlocking" this carbon source in situ. For over two decades, researchers have endeavored to understand which organisms perform these processes. This study provides the first descriptions of organisms with this genetic potential from the coal seam environment. Here, we report metagenomic insights into carbon liberation from aromatic molecules and the degradation pathways involved and describe a Krumholzibacteriota, two Syntrophorhabdus aromaticivorans, and a Syntrophaceae MAG that contain this genetic potential. This is also the first time that the Krumholzibacteriota phylum has been implicated in anaerobic dearomatization of aromatic hydrocarbons. This potential is identified here in numerous MAGs from other terrestrial and marine subsurface habitats, implicating the Krumholzibacteriota in carbon-cycling processes across a broad range of environments.


Assuntos
Carvão Mineral , Deltaproteobacteria , Carvão Mineral/microbiologia , Carbono/metabolismo , Metano/metabolismo , Deltaproteobacteria/metabolismo
19.
Environ Pollut ; 349: 123954, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604307

RESUMO

Agricultural run-off in Australia's Mackay-Whitsunday region is a major source of nutrient and pesticide pollution to coastal and inshore ecosystems of the Great Barrier Reef. While the effects of run-off are well documented for the region's coral and seagrass habitats, the ecological impacts on estuaries, the direct recipients of run-off, are less known. This is particularly true for fish communities, which are shaped by the physico-chemical properties of coastal waterways that vary greatly in tropical regions. To address this knowledge gap, we used environmental DNA (eDNA) metabarcoding to examine fish assemblages at four locations (three estuaries and a harbour) subjected to varying levels of agricultural run-off during a wet and dry season. Pesticide and nutrient concentrations were markedly elevated during the sampled wet season with the influx of freshwater and agricultural run-off. Fish taxa richness significantly decreased in all three estuaries (F = 164.73, P = <0.001), along with pronounced changes in community composition (F = 46.68, P = 0.001) associated with environmental variables (largely salinity: 27.48% contribution to total variance). In contrast, the nearby Mackay Harbour exhibited a far more stable community structure, with no marked changes in fish assemblages observed between the sampled seasons. Among the four sampled locations, variation in fish community composition was more pronounced within the wet season (F = 2.5, P = 0.001). Notably, variation in the wet season was significantly correlated with agricultural contaminants (phosphorus: 6.25%, pesticides: 5.22%) alongside environmental variables (salinity: 5.61%, DOC: 5.57%). Historically contaminated and relatively unimpacted estuaries each demonstrated distinct fish communities, reflecting their associated catchment use. Our findings emphasise that while seasonal effects play a key role in shaping the community structure of fish in this region, agricultural contaminants are also important contributors in estuarine systems.


Assuntos
Agricultura , Recifes de Corais , DNA Ambiental , Monitoramento Ambiental , Peixes , Salinidade , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/análise , Austrália , Praguicidas , Estuários , Ecossistema
20.
Orthop Clin North Am ; 54(4): 463-470, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37718085

RESUMO

Distal radius fractures have a high incidence among both young and elderly patients, and in many instances require operative intervention. When operative intervention is employed, adequate pain management is essential to decrease postoperative complications, such as chronic pain and disability, while minimizing the risk of prolonged opioid use and dependence. Strategies to optimize pain management include regional anesthesia, preoperative dosing of medication, multimodal regimens, long-acting selective opioids at the time of surgery, corticosteroids, and non-pharmacologic therapies.


Assuntos
Dor Crônica , Fraturas do Punho , Idoso , Humanos , Manejo da Dor , Complicações Pós-Operatórias , Analgésicos Opioides/uso terapêutico
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