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1.
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
2.
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
3.
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
4.
Microb Ecol ; 75(3): 811-818, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29018917

RESUMO

The red macroalga Asparagopsis taxiformis has been shown to significantly decrease methane production by rumen microbial communities. This has been attributed to the bioaccumulation of halogenated methane analogues produced as algal secondary metabolites. The objective of this study was to evaluate the impact of A. taxiformis supplementation on the relative abundance of methanogens and microbial community structure during in vitro batch fermentation. Addition of A. taxiformis (2% organic matter) or the halogenated methane analogue bromoform (5 µM) reduced methane production by over 99% compared to a basal substrate-only control. Quantitative PCR confirmed that the decrease in methane production was correlated with a decrease in the relative abundance of methanogens. High-throughput 16S ribosomal RNA gene amplicon sequencing showed that both treatments reduced the abundance of the three main orders of methanogens present in ruminants (Methanobacteriales, Methanomassiliicoccales and Methanomicrobiales). Shifts in bacterial community structure due to the addition of A. taxiformis and 5 µM bromoform were similar and concomitant with increases in hydrogen concentration in the headspace of the fermenters. With high potency and broad-spectrum activity against rumen methanogens, A. taxiformis represents a promising natural strategy for reducing enteric methane emissions from ruminant livestock.


Assuntos
Metano/análogos & derivados , Microbiota/efeitos dos fármacos , Rodófitas/metabolismo , Rúmen/microbiologia , Alga Marinha/metabolismo , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , DNA Bacteriano/genética , Fermentação , Halogenação , Hidrogênio/metabolismo , Técnicas In Vitro , Gado/microbiologia , Metano/metabolismo , Methanobacteriales/efeitos dos fármacos , Methanobacteriales/metabolismo , Methanomicrobiales/efeitos dos fármacos , Methanomicrobiales/metabolismo , Microbiota/genética , RNA Ribossômico 16S/genética , Trialometanos/farmacologia
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
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
12.
Neuromodulation ; 19(8): 864-871, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27284964

RESUMO

BACKGROUND AND AIMS: High-frequency gastric electrical stimulation (GES) has emerged as a therapy for gastroparesis, but the mechanism(s) of action remain unclear. There is a need to refine stimulation protocols for clinical benefit, but a lack of accurate techniques for assessing mechanisms in clinical trials, such as slow wave modulation, has hindered progress. We thereby aimed to assess acute slow wave responses to GES in gastroparesis patients using high-resolution (HR) (multi-electrode) mapping, across a range of stimulation doses achievable by the Enterra stimulation device (Medtronic Inc., MN, USA). MATERIALS AND METHODS: Patients with medically refractory gastroparesis (n = 8) undergoing device implantation underwent intraoperative HR mapping (256 electrodes). Baseline recordings were followed by four protocols of increasing stimulation intensity, with washout periods. Slow wave patterns, frequency, velocity, amplitude, and dysrhythmia rates were quantified by investigators blinded to stimulation settings. RESULTS: There was no difference in slow wave pattern, frequency, velocity, or amplitude between baseline, washout, and stimulation periods (all p > 0.5). Dysrhythmias included ectopic pacemakers, conduction blocks, retrograde propagation, and colliding wavefronts, and dysrhythmia rates were unchanged with stimulation off vs. on (31% vs. 36% duration dysrhythmic; p > 0.5). Symptom scores and gastric emptying were improved at 5.8 month follow-up (p < 0.05). CONCLUSIONS: High-frequency GES protocols achievable from a current commercial device did not acutely modulate slow wave activity or dysrhythmias. This study advances clinical methods for identifying and assessing therapeutic GES parameters, and can be applied in future studies on higher-energy protocols and devices.


Assuntos
Terapia por Estimulação Elétrica/métodos , Gastroparesia/terapia , Adulto , Biofísica , Eletrodos Implantados , Feminino , Esvaziamento Gástrico/fisiologia , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Resultado do Tratamento
13.
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
14.
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
15.
Mycologia ; 105(4): 1043-58, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23709478

RESUMO

The first collection of a macrofungal agaric species, with morphological features similar to already described Anamika species, has been found in association with animal bones in north Queensland, Australia. This species also shares features with several, commonly occurring and previously described Australian Hebeloma species. An integrated morphological and molecular study has resulted in the conclusion that all Anamika species belong in Hebeloma. As a result, already described species of Anamika are recombined as H. indicum (K.A. Thomas, Peintner, M.M. Moser and Manim.) B.J. Rees & Orlovich, H. angustilamellatum (Zhu L. Yang and Z.W. Ge) B.J. Rees & Orlovich and H. lactariolens (Clémençon and Hongo) B.J. Rees & Orlovich. A. phylogenetic tree based on ribosomal ITS sequences examines the relationship of these species with other Hebeloma species from both hemispheres. Four new species, Hebeloma youngii B.J. Rees, H. nothofagetorum B.J. Rees, H. subvictoriense B.J. Rees, H. lacteocoffeatum B.J. Rees, and one form, H. aminophilum f. hygrosarx B.J. Rees, are described as new from Australia.


Assuntos
Hebeloma/classificação , Austrália , Hebeloma/genética , Hebeloma/ultraestrutura , Microscopia Eletrônica de Varredura , Filogenia
16.
J Med Imaging Radiat Oncol ; 67(4): 421-427, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36478391

RESUMO

INTRODUCTION: Lower limb ischaemia secondary to occlusion of a lower limb artery is a limb-threatening condition that can be effectively treated by catheter-directed thrombolysis (CDT). The purpose of this study was to examine treatment outcomes of CDT both at the time of treatment and ongoing patency up to 12 months following treatment. The secondary aim of the study was to investigate the influence of age of occlusion and treatment duration on success and complication rates. METHOD: A retrospective observational study was performed at a single institution over a 10-year period from 2010 to 2019. Data for patient demographics, vessel occlusion factors and treatment information were obtained and analysed. Patency data were investigated using Kaplan-Meier analyses. RESULTS: A total of 218 limbs in 159 patients were treated during the study period. The aetiology of vessel occlusion was in situ thrombosis or occluded bypass graft in 74.5%. Technical success was achieved in 55.5% with CDT alone and 84.4% by using CDT in combination with adjunctive endovascular procedures (angioplasty or stenting). The overall probability of patency was 0.65 at 3 months and 0.44 at 12 months. The overall rate of major amputation within 30 days of thrombolysis was 8.2%. Thirty-day mortality was 6.3% and was secondary to intracranial haemorrhage in three patients. CONCLUSION: Technical success of CDT was found to be significantly higher when combined with adjunctive endovascular procedures at the time of CDT. Despite an initial moderate technical success, the probability of patency at 12 months was only 44%. The likelihood of bleeding complications and technical and long-term success remain key considerations when selecting patients for CDT.


Assuntos
Arteriopatias Oclusivas , Procedimentos Endovasculares , Doenças Vasculares Periféricas , Humanos , Estudos Retrospectivos , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/métodos , Grau de Desobstrução Vascular , Resultado do Tratamento , Isquemia/terapia , Isquemia/tratamento farmacológico , Catéteres/efeitos adversos , Fatores de Risco
17.
J Bacteriol ; 194(6): 1631-2, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22374960

RESUMO

Clostridium sporogenes PA 3679 is widely used as a nontoxigenic surrogate for proteolytic strains of Clostridium botulinum in the derivation and validation of thermal processes in food. Here we report the draft assembly and annotation of the C. sporogenes PA 3679 genome. Preliminary analysis demonstrates a high degree of relatedness between C. sporogenes PA 3679 and sequenced strains of proteolytic C. botulinum.


Assuntos
Clostridium/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Genoma Bacteriano , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência
18.
Arch Microbiol ; 194(6): 513-23, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22245906

RESUMO

Microbial diversity within formation water and oil from two compartments in Bokor oil reservoir from a Malaysian petroleum oil field was examined. A total of 1,056 16S rRNA gene clones were screened from each location by amplified ribosomal DNA restriction analysis. All samples were dominated by clones affiliated with Marinobacter, some novel Deferribacteraceae genera and various clones allied to the Methanococci. In addition, either Marinobacterium- or Pseudomonas-like operational taxonomic units were detected from either compartment. A systematic comparison with the existing pertinent studies was undertaken by analysing the microbial amplicons detected and the PCR primers used. The analyses demonstrated that bacterial communities were site specific, while Archaea co-occurred more frequently. Amplicons related to Marinobacter, Marinobacterium and Pseudomonas were detected in a number of the studies examined, suggesting they may be ubiquitous members in oil reservoirs. Further analysis of primers used in those studies suggested that most primer pairs had fairly broad but low matches across the bacterial and archaeal domains, while a minority had selective matches to certain taxa or low matches to all the microbial taxa tested. Thus, it indicated that primers may play an important role in determining which taxa would be detected.


Assuntos
Archaea/classificação , Biodiversidade , Marinobacter/classificação , Campos de Petróleo e Gás/microbiologia , Pseudomonas/classificação , Archaea/genética , Biologia Computacional , Primers do DNA , DNA Arqueal/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Malásia , Marinobacter/genética , Filogenia , Reação em Cadeia da Polimerase , Pseudomonas/genética , RNA Ribossômico 16S/genética
19.
Forensic Sci Med Pathol ; 8(4): 380-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22615068

RESUMO

To evaluate police and autopsy reports in sudden unexplained deaths in 0-40 year olds. A structured, blind review of police and autopsy reports send to a cardiac genetic service from before (February 2006-December 2007) and after (January-December 2009) new best practice guidelines were introduced in Australia and New Zealand was performed. The reviews focused on reporting on: (1) presentation and clinical history, (2) cardiac autopsy, (3) histological tests and toxicology, and (4) detailed examination of coronary arteries. 110 reports were evaluated against the guidelines. 100 % reported location, 95 % activity at time of death, and 84 % some clinical history. Less than 25 % reported on family history, presence/absence of illicit drugs or alcohol, recorded a possible arrhythmic trigger, or history of fits/faints or collapses. Over 95 % listed heart weight, valvular examinations, pulmonary and some myocardial histology. Less than 50 % commented on septal, LV (left ventricle) and RV (right ventricle) wall thickness. Less than 50 % mentioned site of histology samples, or gave specific description of LV or RV histology or conduction system. Toxicology was not mentioned in a third. Histology of coronary arteries was described in only 18 %. Post guidelines reporting increased in some areas, e.g. in 1-40 year olds: antecedent symptoms (22-61 %), number and location of histology samples (0-47 %), and histology of coronary arteries (6-50 %). Most police and autopsy reports fall short of best practice guidelines. They have improved somewhat after the new guidelines were introduced, but need to be more consistent and particularly need to include significant negative findings.


Assuntos
Autopsia/normas , Morte Súbita/patologia , Documentação/normas , Fidelidade a Diretrizes/estatística & dados numéricos , Polícia , Guias de Prática Clínica como Assunto , Adolescente , Adulto , Criança , Pré-Escolar , Vasos Coronários/patologia , DNA/isolamento & purificação , Diagnóstico por Imagem/estatística & dados numéricos , Documentação/estatística & dados numéricos , Patologia Legal/normas , Átrios do Coração/patologia , Sistema de Condução Cardíaco/patologia , Septos Cardíacos/patologia , Ventrículos do Coração/patologia , Humanos , Lactente , Recém-Nascido , Pulmão/patologia , Anamnese , Valva Mitral/patologia , Miocárdio/patologia , Nova Zelândia , Manejo de Espécimes/estatística & dados numéricos , Adulto Jovem
20.
Microb Genom ; 8(8)2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35997693

RESUMO

One of the most abundant and ubiquitous taxa observed in eastern Australian coal seams is an uncultured Desulfuromonas species and part of the Coal Seam Microbiome dataset assigned as 'CSMB_57'. Despite this abundance and ubiquity, knowledge about this taxon is limited. The present study aimed to generate an enrichment culture of Desulfuromonas sp. 'CSMB_57' using culturing strategies that exploit its sulphur-reducing capabilities by utilizing a polysulfide solution in a liquid medium. Using dilution to extinction methods, a highly enriched culture was successfully generated. The full-length 16S rRNA sequence revealed that all closely related taxa were observed in subsurface environments suggesting that D. sp. 'CSMB_57' may be a subsurface specialist. Subsequently, the DNA from the enrichment culture was sequenced and the genome of D. sp. 'CSMB_57' was assembled. Genomic annotation revealed a high number of CRISPR arrays for viral defence, a large array of ABC transporters for amino acid and peptide uptake, as well as genes likely associated with syntrophy such as genes associated with type-IVa pilus, often used for direct interspecies electron transfer, and multiple hydrogenases capable of producing hydrogen. From the various genomic observations, a conceptual ecological model was developed that explores its possible syntrophic roles with hydrogenotrophic methanogens and acetogenic bacteria within coal-seam environments.


Assuntos
Carvão Mineral , Desulfuromonas , Austrália , Bactérias , Carvão Mineral/microbiologia , Desulfuromonas/genética , Genômica , RNA Ribossômico 16S/genética
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