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1.
Braz J Microbiol ; 55(2): 1811-1816, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38739216

RESUMEN

As the prevalence of drug-resistant Candida isolates continues to rise, the imperative for identifying novel compounds to enhance the arsenal of antifungal drugs becomes increasingly critical. Consequently, exploring new treatment strategies, including synthesizing molecular hybrids and applying combination therapy, is essential. For this reason, this study evaluated the efficacy of ten molecular hybrids of aza-bicyclic 2-isoxazoline-acylhydrazone belonging to two series 90 and 91 as possible anti-Candida agents. In addition, we also investigated the interaction between the hybrids and fluconazole, a commonly used antifungal drug. We evaluated the antifungal effect of aza-bicyclic 2-isoxazoline-acylhydrazone hybrid compounds against six Candida spp. strains that target planktonic cells. However, none of these new molecules were inhibitory active at the tested concentrations (2 to 1,024 µg/mL). Moreover, we analyzed the interaction between the ten new hybrid molecules and fluconazole using the checkerboard assay, employing two different methodologies for reading the plate. For this, one isolate fluconazole-resistant was selected. We observed that only one combination, 6-(4-tert-butylbenzoil)-4,5,6,6a-tetrahydro-3a-H-pirrole[3,2-d]isoxazole-3-carboxylic(furan-2-metilidene)-hydrazide (91e) and fluconazole, exhibited a synergistic interaction (FICI range 0.0781 to 0.4739). The combination successfully inhibited the growth of C. albicans CA2 fluconazole-resistant, and no interaction was observed in an isolate susceptible to fluconazole. Additionally, these results emphasize the continued need for research into new compounds and the importance of using combined approaches to increase their activity.


Asunto(s)
Antifúngicos , Candida albicans , Farmacorresistencia Fúngica , Sinergismo Farmacológico , Fluconazol , Hidrazonas , Isoxazoles , Pruebas de Sensibilidad Microbiana , Antifúngicos/farmacología , Antifúngicos/química , Fluconazol/farmacología , Candida albicans/efectos de los fármacos , Hidrazonas/farmacología , Hidrazonas/química , Isoxazoles/farmacología , Isoxazoles/química , Humanos
2.
Environ Pollut ; 347: 123725, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38467369

RESUMEN

Methylmercury (MeHg) is one of the most worrisome pollutants in marine systems. MeHg detoxification is mediated by merB and merA genes, responsible for the demethylation of MeHg and the reduction of inorganic mercury, respectively. Little is known about the biological capacity to detoxify this compound in marine environments, and even less the bacterial transcriptional changes during MeHg detoxification. This study provides the genomic and transcriptomic characterization of the deep ocean bacteria Alteromonas mediterranea ISS312 with capacity for MeHg degradation. Its genome sequence revealed four mer operons containing three merA gene and two merB gene copies, that could be horizontally transferred among distant related genomes by mobile genetic elements. The transcriptomic profiling in the presence of 5 µM MeHg showed that merA and merB genes are within the most expressed genes, although not all mer genes were equally transcribed. Besides, we aimed to identify functional orthologous genes that displayed expression profiles highly similar or identical to those genes within the mer operons, which could indicate they are under the same regulatory controls. We found contrasting expression profiles for each mer operon that were positively correlated with a wide array of functions mostly related to amino acid metabolism, but also to flagellar assembly or two component systems. Also, this study highlights that all merAB genes of the four operons were globally distributed across oceans layers with higher transcriptional activity in the mesopelagic deeper waters. Our study provides new insights about the transcriptional patterns related to the capacity of marine bacteria to detoxify MeHg, with important implications for the understanding of this process in marine ecosystems.


Asunto(s)
Alteromonas , Mercurio , Compuestos de Metilmercurio , Compuestos de Metilmercurio/metabolismo , Ecosistema , Mercurio/metabolismo , Bacterias/metabolismo , Perfilación de la Expresión Génica , Genómica
3.
Sci Data ; 11(1): 154, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302528

RESUMEN

The Ocean microbiome has a crucial role in Earth's biogeochemical cycles. During the last decade, global cruises such as Tara Oceans and the Malaspina Expedition have expanded our understanding of the diversity and genetic repertoire of marine microbes. Nevertheless, there are still knowledge gaps regarding their diversity patterns throughout depth gradients ranging from the surface to the deep ocean. Here we present a dataset of 76 microbial metagenomes (MProfile) of the picoplankton size fraction (0.2-3.0 µm) collected in 11 vertical profiles covering contrasting ocean regions sampled during the Malaspina Expedition circumnavigation (7 depths, from surface to 4,000 m deep). The MProfile dataset produced 1.66 Tbp of raw DNA sequences from which we derived: 17.4 million genes clustered at 95% sequence similarity (M-GeneDB-VP), 2,672 metagenome-assembled genomes (MAGs) of Archaea and Bacteria (Malaspina-VP-MAGs), and over 100,000 viral genomic sequences. This dataset will be a valuable resource for exploring the functional and taxonomic connectivity between the photic and bathypelagic tropical and sub-tropical ocean, while increasing our general knowledge of the Ocean microbiome.


Asunto(s)
Metagenoma , Plancton , Archaea/genética , Bacterias/genética , Océanos y Mares , Plancton/genética
4.
Chemosphere ; 349: 140743, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37984648

RESUMEN

In an attempt to assess the diversity of viruses and their potential to modulate the metabolism of functional microorganisms in anaerobic digesters, we collected digestate from three mesophilic anaerobic digesters in full-scale wastewater treatment plants treating real municipal wastewater. The reads were analyzed using bioinformatics algorithms to elucidate viral diversity, identify their potential role in modulating the metabolism of functional microorganisms, and provide essential genomic information for the potential use of virus-mediated treatment in controlling the anaerobic digester microbiome. We found that Siphoviridae was the dominant family in mesophilic anaerobic digesters, followed by Myoviridae and Podoviridae. Lysogeny was prevalent in mesophilic anaerobic digesters as the majority of metagenome-assembled genomes contained at least one viral genome within them. One virus within the genome of an acetoclastic methanogen (Methanothrix soehngenii) was observed with a gene (fwdE) acquired via lateral transfer from hydrogenotrophic methanogens. The virus-mediated acquisition of fwdE gene enables possibility of mixotrophic methanogenesis in Methanothrix soehngenii. This evidence highlighted that lysogeny provides fitness advantage to methanogens in anaerobic digesters by adding flexibility to changing substrates. Similarly, we found auxiliary metabolic genes, such as cellulase and alpha glucosidase, of bacterial origin responsible for sludge hydrolysis in viruses. Additionally, we discovered novel viral genomes and provided genomic information on viruses infecting acidogenic, acetogenic, and pathogenic bacteria that can potentially be used for virus-mediated treatment to deal with the souring problem in anaerobic digesters and remove pathogens from biosolids before land application. Collectively, our study provides a genome-level understanding of virome in conjunction with the microbiome in anaerobic digesters that can be used to optimize the anaerobic digestion process for efficient biogas generation.


Asunto(s)
Reactores Biológicos , Metano , Anaerobiosis , Reactores Biológicos/microbiología , Metano/metabolismo , Bacterias/metabolismo , Aguas del Alcantarillado
5.
Microbiome ; 11(1): 118, 2023 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-37237317

RESUMEN

BACKGROUND: Viruses play important roles in the ocean's biogeochemical cycles. Yet, deep ocean viruses are one of the most under-explored fractions of the global biosphere. Little is known about the environmental factors that control the composition and functioning of their communities or how they interact with their free-living or particle-attached microbial hosts. RESULTS: We analysed 58 viral communities associated with size-fractionated free-living (0.2-0.8 µm) and particle-attached (0.8-20 µm) cellular metagenomes from bathypelagic (2150-4018 m deep) microbiomes obtained during the Malaspina expedition. These metagenomes yielded 6631 viral sequences, 91% of which were novel, and 67 represented high-quality genomes. Taxonomic classification assigned 53% of the viral sequences to families of tailed viruses from the order Caudovirales. Computational host prediction associated 886 viral sequences to dominant members of the deep ocean microbiome, such as Alphaproteobacteria (284), Gammaproteobacteria (241), SAR324 (23), Marinisomatota (39), and Chloroflexota (61). Free-living and particle-attached viral communities had markedly distinct taxonomic composition, host prevalence, and auxiliary metabolic gene content, which led to the discovery of novel viral-encoded metabolic genes involved in the folate and nucleotide metabolisms. Water mass age emerged as an important factor driving viral community composition. We postulated this was due to changes in quality and concentration of dissolved organic matter acting on the host communities, leading to an increase of viral auxiliary metabolic genes associated with energy metabolism among older water masses. CONCLUSIONS: These results shed light on the mechanisms by which environmental gradients of deep ocean ecosystems structure the composition and functioning of free-living and particle-attached viral communities. Video Abstract.


Asunto(s)
Microbiota , Virus , Agua de Mar/microbiología , Agua , Genes Virales , Virus/genética , Microbiota/genética , Océanos y Mares
6.
PLoS Biol ; 21(4): e3002083, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37083735

RESUMEN

The extraordinary diversity of viruses infecting bacteria and archaea is now primarily studied through metagenomics. While metagenomes enable high-throughput exploration of the viral sequence space, metagenome-derived sequences lack key information compared to isolated viruses, in particular host association. Different computational approaches are available to predict the host(s) of uncultivated viruses based on their genome sequences, but thus far individual approaches are limited either in precision or in recall, i.e., for a number of viruses they yield erroneous predictions or no prediction at all. Here, we describe iPHoP, a two-step framework that integrates multiple methods to reliably predict host taxonomy at the genus rank for a broad range of viruses infecting bacteria and archaea, while retaining a low false discovery rate. Based on a large dataset of metagenome-derived virus genomes from the IMG/VR database, we illustrate how iPHoP can provide extensive host prediction and guide further characterization of uncultivated viruses.


Asunto(s)
Archaea , Virus , Archaea/genética , Metagenoma/genética , Virus/genética , Bacterias/genética , Metagenómica/métodos , Aprendizaje Automático , Genoma Viral/genética
7.
Microb Ecol ; 86(3): 2202-2209, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37017718

RESUMEN

The microbiome is fundamental for understanding bacterial activities in sediments. However, only a limited number of studies have addressed the microbial diversity of Amazonian sediments. Here, we studied the microbiome of sediments from a 13,000-year BP core retrieved in a floodplain lake in Amazonia using metagenomics and biogeochemistry. Our aim was to evaluate the possible environmental influence over a river to a lake transition using a core sample. To this end, we sampled a core in the Airo Lake, a floodplain lake in the Negro River basin. The Negro River is the largest tributary of the Amazon River. The obtained core was divided into three strata: (i) surface, almost complete separation of the Airo Lake from the Negro River when the environment becomes more lentic with greater deposition of organic matter (black-colored sediment); (ii) transitional environment (reddish brown); and (iii) deep, environment with a tendency for greater past influence of the Negro River (brown color). The deepest sample possibly had the greatest influence of the Negro River as it represented the bottom of this river in the past, while the surface sample is the current Airo Lake bottom. In total, six metagenomes were obtained from the three different depth strata (total number of reads: 10.560.701; sequence length: 538 ± 24, mean ± standard deviation). The older (deeper) sediment strata contained a higher abundance of Burkholderia, Chitinophaga, Mucilaginibacter, and Geobacter, which represented ~ 25% of the metagenomic sequences. On the other hand, the more recent sediment strata had mainly Thermococcus, Termophilum, Sulfolobus, Archaeoglobus, and Methanosarcina (in total 11% of the metagenomic sequences). The sequence data were binned into metagenome-assembled genomes (MAGs). The majority of the obtained MAGs (n = 16) corresponded to unknown taxa, suggesting they may belong to new species. The older strata sediment microbiome was enriched with sulfur cycle genes, TCA cycle, YgfZ, and ATP-dependent proteolysis in bacteria. Meanwhile, serine-glyoxylate cycle, stress response genes, bacterial cell division, cell division-ribosomal stress protein cluster, and oxidative stress increased in the younger strata. Metal resistance and antimicrobial resistance genes were found across the entire core, including genes coding for fluoroquinolones, polymyxin, vancomycin, and multidrug resistance transporters. These findings depict the possible microbial diversity during the depositional past events and provided clues of the past microbial metabolism throughout time.


Asunto(s)
Microbiota , Microbiota/genética , Bacterias , Metagenoma , Ríos/microbiología , Lagos/microbiología , Sedimentos Geológicos/microbiología
8.
Sci Total Environ ; 862: 160822, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36526191

RESUMEN

Aquifers have significant social, economic, and ecological importance. They supply 30 % of the freshwater for human consumption worldwide, including agricultural and industrial use. Despite aquifers' importance, the relationships between aquifer categories and their inhabiting microbial communities are still unknown. Characterizing variations within microbial communities' function and taxonomy structure at different aquifers could give a panoramic view of patterns that may enable the detection and prediction of environmental impact caused by multiple sources. Using publicly available shotgun metagenomic datasets, we examined whether soil properties, land use, and climate variables would have a more significant influence on the taxonomy and functional structure of the microbial communities than the ecological landscapes of the aquifer (i.e., Karst, Porous, Saline, Geyser, and Porous Contaminated). We found that these categories are stronger predictors of microbial communities' structure than geographical localization. In addition, our results show that microbial richness and dominance patterns are the opposite of those found in multicellular life, where extreme habitats harbour richer functional and taxonomic microbial communities. We found that low-abundant and recently described candidate taxa, such as the chemolithoautotrophic genus Candidatus Altiarcheum and the Candidate phylum Parcubacteria, are the main contributors to aquifer microbial communities' dissimilarities. Genes related to gram-negative bacteria proteins, cell wall structures, and phage activity were the primary contributors to aquifer microbial communities' dissimilarities among the aquifers' ecological landscapes. The results reported in the present study highlight the utility of using ecological landscapes for investigating aquifer microbial communities. In addition, we suggest that functions played by recently described and low abundant bacterial groups need further investigation once they might affect water quality, geochemical cycles, and the effects of anthropogenic disturbances such as pollution and climatic events on aquifers.


Asunto(s)
Agua Subterránea , Microbiota , Humanos , Agua Subterránea/química , Bacterias/metabolismo , Calidad del Agua , Bacterias Gramnegativas
9.
Curr Top Med Chem ; 22(4): 247-258, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-34986770

RESUMEN

BACKGROUND: In a study recently published by our research group, the isoxazoline-acylhydrazone derivatives R-99 and R-123 presented promising antinociceptive activity. However, the mechanism of action of this compound is still unknown. OBJECTIVE: This study aimed to assess the mechanisms involved in the antinociceptive activity of these compounds in chemical models of pain. METHODS: Animals were orally pretreated and evaluated in the acetic acid-, formalin-, capsaicin-, carrageenan- and Complete Freund's Adjuvant (CFA)-induced pain models in mice. The effects of the compounds after pretreatment with naloxone, prazosin, yohimbine, atropine, L-arginine, or glibenclamide were studied, using the acetic acid-induced writhing test to verify the possible involvement of opioid, α1-adrenergic, α2-adrenergic or cholinergic receptors, and nitric oxide or potassium channels pathways, respectively. RESULTS: R-99 and R-123 compounds showed significant antinociceptive activity on pain models induced by acetic acid, formalin, and capsaicin. Both compounds decreased the mechanical hyperalgesia induced by carrageenan or CFA in mice. The antinociceptive effects of R-99 and R-123 on the acetic acid-induced writhing test were significantly attenuated by pretreatment with naloxone, yohimbine or atropine. R-99 also showed an attenuated response after pretreatment with atropine and glibenclamide. However, on the pretreatment with prazosin, there was no change in the animals' response to both compounds. CONCLUSION: R-99 and R-123 showed antinociceptive effects related to mechanisms that involve, at least in part, interaction with the opioid and adrenergic systems and TRPV1 pathways. The compound R-99 also interacts with the cholinergic pathways and potassium channels.


Asunto(s)
Analgésicos , Nocicepción , Analgésicos/farmacología , Analgésicos/uso terapéutico , Analgésicos Opioides/efectos adversos , Animales , Ratones , Dolor/tratamiento farmacológico , Extractos Vegetales/química
10.
Microbiol Spectr ; 10(1): e0231821, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-34985337

RESUMEN

Lignocellulose degradation by microbial consortia is multifactorial; hence, it must be analyzed from a holistic perspective. In this study, the temporal transcriptional activity of consortium PM-06, a nixtamalized maize pericarp (NMP) degrader, was determined and related to structural and physicochemical data to give insights into the mechanism used to degrade this substrate. Transcripts were described in terms of metabolic profile, carbohydrate-active enzyme (CAZyme) annotation, and taxonomic affiliation. The PM-06 gene expression pattern was closely related to the differential rates of degradation. The environmental and physiological conditions preceding high-degradation periods were crucial for CAZyme expression. The onset of degradation preceded the period with the highest degradation rate in the whole process, and in this time, several CAZymes were upregulated. Functional analysis of expressed CAZymes indicated that PM-06 overcomes NMP recalcitrance through modular enzymes operating at the proximity of the insoluble substrate. Increments in the diversity of expressed modular CAZymes occurred in the last stages of degradation where the substrate is more recalcitrant and environmental conditions are stressing. Taxonomic affiliation of CAZyme transcripts indicated that Paenibacillus macerans was fundamental for degradation. This microorganism established synergistic relationships with Bacillus thuringiensis for the degradation of cellulose and hemicellulose and with Microbacterium, Leifsonia, and Nocardia for the saccharification of oligosaccharides. IMPORTANCE Nixtamalized maize pericarp is an abundant residue of the tortilla industry. Consortium PM-06 efficiently degraded this substrate in 192 h. In this work, the temporal transcriptional profile of PM-06 was determined. Findings indicated that differential degradation rates are important sample selection criteria since they were closely related to the expression of carbohydrate-active enzymes (CAZymes). The initial times of degradation were crucial for the consumption of nixtamalized pericarp. A transcriptional profile at the onset of degradation is reported for the first time. Diverse CAZyme genes were rapidly transcribed after inoculation to produce different enzymes that participated in the stage with the highest degradation rate in the whole process. This study provides information about the regulation of gene expression and mechanisms used by PM-06 to overcome recalcitrance. These findings are useful in the design of processes and enzyme cocktails for the degradation of this abundant substrate.


Asunto(s)
Bacterias/genética , Bacterias/metabolismo , Consorcios Microbianos , Zea mays/microbiología , Bacterias/clasificación , Bacterias/aislamiento & purificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Celulosa/metabolismo , Perfilación de la Expresión Génica , Lignina/metabolismo , Polisacáridos/metabolismo , Transcriptoma , Zea mays/metabolismo
11.
Nat Commun ; 12(1): 6965, 2021 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-34845206

RESUMEN

The host range of bacteriophages defines their impact on bacterial communities and genome diversity. Here, we characterize 94 novel staphylococcal phages from wastewater and establish their host range on a diversified panel of 117 staphylococci from 29 species. Using this high-resolution phage-bacteria interaction matrix, we unveil a multi-species host range as a dominant trait of the isolated staphylococcal phages. Phage genome sequencing shows this pattern to prevail irrespective of taxonomy. Network analysis between phage-infected bacteria reveals that hosts from multiple species, ecosystems, and drug-resistance phenotypes share numerous phages. Lastly, we show that phages throughout this network can package foreign genetic material enclosing an antibiotic resistance marker at various frequencies. Our findings indicate a weak host specialism of the tested phages, and therefore their potential to promote horizontal gene transfer in this environment.


Asunto(s)
Genoma Viral , Especificidad del Huésped , Fagos de Staphylococcus/genética , Staphylococcus/genética , Aguas Residuales , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Ecosistema , Transferencia de Gen Horizontal , Consorcios Microbianos/genética , Pruebas de Sensibilidad Microbiana , Filogenia , Staphylococcus/clasificación , Staphylococcus/efectos de los fármacos , Staphylococcus/virología , Fagos de Staphylococcus/clasificación , Fagos de Staphylococcus/aislamiento & purificación , Aguas Residuales/microbiología , Aguas Residuales/virología , Microbiología del Agua
12.
Front Microbiol ; 12: 701414, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34650523

RESUMEN

Viruses play vital biogeochemical and ecological roles by (a) expressing auxiliary metabolic genes during infection, (b) enhancing the lateral transfer of host genes, and (c) inducing host mortality. Even in harsh and extreme environments, viruses are major players in carbon and nutrient recycling from organic matter. However, there is much that we do not yet understand about viruses and the processes mediated by them in the extreme environments such as hypersaline habitats. The Great Salt Lake (GSL) in Utah, United States is a hypersaline ecosystem where the biogeochemical role of viruses is poorly understood. This study elucidates the diversity of viruses and describes virus-host interactions in GSL sediments along a salinity gradient. The GSL sediment virosphere consisted of Haloviruses (32.07 ± 19.33%) and members of families Siphoviridae (39.12 ± 19.8%), Myoviridae (13.7 ± 6.6%), and Podoviridae (5.43 ± 0.64%). Our results demonstrate that salinity alongside the concentration of organic carbon and inorganic nutrients (nitrogen and phosphorus) governs the viral, bacteria, and archaeal diversity in this habitat. Computational host predictions for the GSL viruses revealed a wide host range with a dominance of viruses that infect Proteobacteria, Actinobacteria, and Firmicutes. Identification of auxiliary metabolic genes for photosynthesis (psbA), carbon fixation (rbcL, cbbL), formaldehyde assimilation (SHMT), and nitric oxide reduction (NorQ) shed light on the roles played by GSL viruses in biogeochemical cycles of global relevance.

13.
Patterns (N Y) ; 2(7): 100274, 2021 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-34286299

RESUMEN

Culture-independent approaches have recently shed light on the genomic diversity of viruses of prokaryotes. One fundamental question when trying to understand their ecological roles is: which host do they infect? To tackle this issue we developed a machine-learning approach named Random Forest Assignment of Hosts (RaFAH), that uses scores to 43,644 protein clusters to assign hosts to complete or fragmented genomes of viruses of Archaea and Bacteria. RaFAH displayed performance comparable with that of other methods for virus-host prediction in three different benchmarks encompassing viruses from RefSeq, single amplified genomes, and metagenomes. RaFAH was applied to assembled metagenomic datasets of uncultured viruses from eight different biomes of medical, biotechnological, and environmental relevance. Our analyses led to the identification of 537 sequences of archaeal viruses representing unknown lineages, whose genomes encode novel auxiliary metabolic genes, shedding light on how these viruses interfere with the host molecular machinery. RaFAH is available at https://sourceforge.net/projects/rafah/.

14.
BMC Microbiol ; 21(1): 220, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34294041

RESUMEN

BACKGROUND: The high incidence of bacterial genes that confer resistance to last-resort antibiotics, such as colistin, caused by mobilized colistin resistance (mcr) genes, poses an unprecedented threat to human health. Understanding the spread, evolution, and distribution of such genes among human populations will help in the development of strategies to diminish their occurrence. To tackle this problem, we investigated the distribution and prevalence of potential mcr genes in the human gut microbiome using a set of bioinformatics tools to screen the Unified Human Gastrointestinal Genome (UHGG) collection for the presence, synteny and phylogeny of putative mcr genes, and co-located antibiotic resistance genes. RESULTS: A total of 2079 antibiotic resistance genes (ARGs) were classified as mcr genes in 2046 metagenome assembled genomes (MAGs), distributed across 1596 individuals from 41 countries, of which 215 were identified in plasmidial contigs. The genera that presented the largest number of mcr-like genes were Suterella and Parasuterella. Other potential pathogens carrying mcr genes belonged to the genus Vibrio, Escherichia and Campylobacter. Finally, we identified a total of 22,746 ARGs belonging to 21 different classes in the same 2046 MAGs, suggesting multi-resistance potential in the corresponding bacterial strains, increasing the concern of ARGs impact in the clinical settings. CONCLUSION: This study uncovers the diversity of mcr-like genes in the human gut microbiome. We demonstrated the cosmopolitan distribution of these genes in individuals worldwide and the co-presence of other antibiotic resistance genes, including Extended-spectrum Beta-Lactamases (ESBL). Also, we described mcr-like genes fused to a PAP2-like domain in S. wadsworthensis. These novel sequences increase our knowledge about the diversity and evolution of mcr-like genes. Future research should focus on activity, genetic mobility and a potential colistin resistance in the corresponding strains to experimentally validate those findings.


Asunto(s)
Colistina/farmacología , Farmacorresistencia Bacteriana/genética , Genes Bacterianos/genética , Microbiota/efectos de los fármacos , Microbiota/genética , Biología Computacional , Transferencia de Gen Horizontal , Variación Genética , Humanos
15.
Appl Environ Microbiol ; 87(18): e0064621, 2021 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-34232732

RESUMEN

Flow from high-magnitude springs fed by the Floridan aquifer system contributes hundreds of liters of water per second to rivers, creating unique lotic systems. Despite their importance as freshwater sources and their contributions to the state's major rivers, little is known about the composition and spatiotemporal variability of prokaryotic and viral communities of these spring systems or their influence on downstream river sites. At four time points throughout a year, we determined the abundance and diversity of prokaryotic and viral communities at three sites within the first-magnitude Manatee Springs system (the spring head where water emerges from the aquifer, a mixed region where the spring run ends, and a downstream site in the Suwannee River). The abundance of prokaryotes and virus-like particles increased 100-fold from the spring head to the river and few members from the head communities persisted in the river at low abundance, suggesting the springs play a minor role in seeding downstream communities. Prokaryotic and viral communities within Manatee Springs clustered by site, with seasonal variability likely driven by flow. As water flowed through the system, microbial community composition was affected by changes in physiochemical parameters and community coalescence. Evidence of species sorting and mass effects could be seen in the assemblages. Greater temporal fluctuations were observed in prokaryotic and viral community composition with increasing distance from the spring outflow, reflecting the relative stability of the groundwater environment, and comparisons to springs from prior work reaffirmed that distinct first-magnitude springs support unique communities. IMPORTANCE Prokaryotic and viral communities are central to food webs and biogeochemical processes in aquatic environments, where they help maintain ecosystem health. The Floridan aquifer system (FAS), which is the primary drinking water source for millions of people in the southeastern United States, contributes large amounts of freshwater to major river systems in Florida through its springs. However, there is a paucity of information regarding the spatiotemporal dynamics of microbial communities in these essential flowing freshwater systems. This work explored the prokaryotic and viral communities in a first-magnitude spring system fed by the FAS that discharges millions of liters of water per day into the Suwannee River. This study examined microbial community composition through space and time as well as the environmental parameters and metacommunity assembly mechanisms that shape these communities, providing a foundational understanding for monitoring future changes.


Asunto(s)
Manantiales Naturales/microbiología , Células Procariotas , Virus , Florida , Agua Dulce/microbiología , Genoma Viral , ARN Ribosómico 16S , Virus/genética , Microbiología del Agua
16.
Rev. bras. cir. plást ; 36(3): 366-372, jul.-set. 2021.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1365554

RESUMEN

RESUMO Introdução: A mamoplastia é uma das cirurgias mais realizadas pelos cirurgiões plásticos. Como todo procedimento, não é isenta de riscos ou complicações. Objetivos: Discutir questões controversas e intercorrências em cirurgia mamária e principais tratamentos. Métodos: Participaram da discussão quatro membros titulares da SBCP com ampla experiência em cirurgia plástica mamária, além do regente do capítulo de mamoplastias. Foram avaliados fatores que apresentavam maior controvérsia em mamoplastias: utilização de antibióticos; infiltração pré-operatória; associação da mamoplastia com implantes mamários; grandes ptoses mamárias; mamoplastia masculinizadora; retalhos para ascensão do complexo areolopapilar (CAP); utilização de drenos; curativos em mamoplastias e enxerto de gordura. Resultados: A literatura e discussão entre especialistas gerou as observações: há evidencias robustas da efetividade no uso de antibióticos perioperatório de mamoplastias redutoras, mas não há evidências de benefícios em se manter o uso por mais de 24 horas; a infiltração pré- operatória com soluções vasoconstritoras não reduz a incidência de hematoma; em mamoplastia associada a implantes não houve consenso sobre a melhor técnica, plano ou textura do implante; não houve consenso sobre a melhor técnica na ascensão do CAP em grandes ptoses, se enxertos ou retalhos; a mamoplastia masculinizadora não apresenta complicações diversas das encontradas na literatura; não existe protocolo específico para conduta quando há sofrimento do CAP; curativos podem ser removidos no primeiro dia de pós-operatório ou mantidos por mais tempo, e deve haver parcimônia no enxerto de gordura. Conclusão: O presente estudo concluiu que a mamoplastia é uma cirurgia segura, porém são necessários estudos continuados que possibilitem minimizar complicações.


ABSTRACT Introduction: Mammoplasty is one of the most performed surgeries by plastic surgeons. Like every procedure, it is not free of risks or complications. Objectives: Discuss controversial issues and complications in breast surgery and main treatments. Methods: Four full members of the SBCP with extensive experience in breast plastic surgery participated in the discussion, in addition to the regent of the mammoplasty chapter. Factors that presented the greatest controversy in mammoplasties were evaluated: use of antibiotics; preoperative infiltration; association of mammoplasty with breast implants; large mammary ptoses; masculinizing mammoplasty; flaps for the elevation of the nipple-areola complex (NAC); use of drains; dressings in mammoplasties and fat grafting. Results: The literature and discussion among specialists generated the observations: there is robust evidence of the effectiveness in the use of perioperative antibiotics of reducing mammoplasties, but there is no evidence of benefits in maintaining use for more than 24 hours; preoperative infiltration with vasoconstrictor solutions does not reduce the incidence of hematoma; in mammoplasty associated with implants there was no consensus on the best technique, plane or texture of the implant; there was no consensus on the best technique in the elevation of NAC in large ptoses, whether grafts or flaps; masculinizing mammoplasty does not present complications different from those found in the literature; there is no specific protocol for conduct when there is suffering from the NAC; dressings can be removed on the first postoperative day or kept longer, and there should be parsimony in the fat graft. Conclusion: The present study concluded that mammoplasty is safe surgery, but continued studies are needed to minimize complications.

17.
Microorganisms ; 9(6)2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34064105

RESUMEN

Roseobacters are globally abundant bacteria with critical roles in carbon and sulfur biogeochemical cycling. Here, we identified 173 new putative prophages in 79 genomes of Rhodobacteraceae. These prophages represented 1.3 ± 0.15% of the bacterial genomes and had no to low homology with reference and metagenome-assembled viral genomes from aquatic and terrestrial ecosystems. Among the newly identified putative prophages, 35% encoded auxiliary metabolic genes (AMGs), mostly involved in secondary metabolism, amino acid metabolism, and cofactor and vitamin production. The analysis of integration sites and gene homology showed that 22 of the putative prophages were actually gene transfer agents (GTAs) similar to a GTA of Rhodobacter capsulatus. Twenty-three percent of the predicted prophages were observed in the TARA Oceans viromes generated from free viral particles, suggesting that they represent active prophages capable of induction. The distribution of these prophages was significantly associated with latitude and temperature. The prophages most abundant at high latitudes encoded acpP, an auxiliary metabolic gene involved in lipid synthesis and membrane fluidity at low temperatures. Our results show that prophages and gene transfer agents are significant sources of genomic diversity in roseobacter, with potential roles in the ecology of this globally distributed bacterial group.

18.
Environ Microbiol Rep ; 13(3): 348-354, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34018688

RESUMEN

Viruses are now recognized as important players in microbial dynamics and biogeochemical cycles in the oceans. Yet, compared with aquatic ecosystems, virus discovery in terrestrial ecosystems has been challenging partly due to the inherent complexity of soils. To expand our understanding of soil viruses and their putative contributions to soil microbial processes, we analysed metagenomes of community-level virus-enriched suspensions by tangential flow filtration obtained from two French agricultural soils. We found viral sequences representing a total of 239 viral operational taxonomic units that corresponded to 29.5% of the mapping reads in the metagenomic datasets. The analysis of their genomic sequences revealed novel virocell metabolic potential with implications to virus-host interactions, carbon cycling, plant-beneficial functions in the rhizosphere, horizontal gene transfer and other relevant microbial strategies applied to survive in soils.


Asunto(s)
Metagenoma , Virus , Ecosistema , Rizosfera , Suelo , Virus/genética
19.
Front Microbiol ; 12: 637430, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33815323

RESUMEN

BACKGROUND: SARS-CoV-2 is an RNA virus causing COVID-19. The clinical characteristics and epidemiology of COVID-19 have been extensively investigated, however, only one study so far focused on the patient's nasopharynx microbiota. In this study we investigated the nasopharynx microbial community of patients that developed different severity levels of COVID-19. We performed 16S ribosomal DNA sequencing from nasopharyngeal swab samples obtained from SARS-CoV-2 positive (56) and negative (18) patients in the province of Alicante (Spain) in their first visit to the hospital. Positive SARS-CoV-2 patients were observed and later categorized in mild (symptomatic without hospitalization), moderate (hospitalization), and severe (admission to ICU). We compared the microbiota diversity and OTU composition among severity groups and built bacterial co-abundance networks for each group. RESULTS: Statistical analysis indicated differences in the nasopharyngeal microbiome of COVID19 patients. 62 OTUs were found exclusively in SARS-CoV-2 positive patients, mostly classified as members of the phylum Bacteroidota (18) and Firmicutes (25). OTUs classified as Prevotella were found to be significantly more abundant in patients that developed more severe COVID-19. Furthermore, co-abundance analysis indicated a loss of network complexity among samples from patients that later developed more severe symptoms. CONCLUSION: Our study shows that the nasopharyngeal microbiome of COVID-19 patients showed differences in the composition of specific OTUs and complexity of co-abundance networks. Taxa with differential abundances among groups could serve as biomarkers for COVID-19 severity. Nevertheless, further studies with larger sample sizes should be conducted to validate these results.

20.
FEMS Microbiol Ecol ; 96(12)2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33289802

RESUMEN

The increasing demand for products for human consumption is leading to the fast-growing expansion of numerous food sectors such as marine aquaculture (mariculture). However, excessive input of nutrients and pollutants modifies marine ecosystems. Here, we applied a metagenomic approach to investigate these perturbations in samples from marine farms of gilthead seabream cultures. Results revealed dysbiosis and functional imbalance within the net cage with a unique structure, with little interference with samples from the fish microbiota or those collected far away from the coast. Remarkably, below the cage the prokaryotic community was highly similar to the marine microbiome of photic offshore samples. We recovered 48 novel metagenome-assembled genomes. Metagenomic recruitment revealed a significant change in the microbial community which was dominated by several Proteobacteria orders (Sphingomonadales, Pseudomonadales, Caudobacterales and Rhizobiales). Genomic potential for bioremediation processes, including nitrate removal through aerobic denitrification, and degradation of aromatic compounds and other toxic products were enriched in these microbes. The detrimental side effects were the increased number of antimicrobial resistance genes and the presence of potentially emergent pathogens. Knowledge of this metabolic diversity and the microbes involved in ecological balance recovery can be used to reduce the environmental impact of these practices.


Asunto(s)
Disbiosis , Microbiota , Animales , Acuicultura , Bacterias/genética , Humanos , Metagenoma , Metagenómica
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