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1.
BMC Infect Dis ; 20(1): 672, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938418

RESUMO

BACKGROUND: Mycobacterium jacuzzii (M. jacuzzii) was first isolated in 2003 by insertion of breast implants in Tel Aviv, Israel. In this case report, we describe our experience in detection of M. jacuzzii using phenotypic and genotypic test of wrist synovial sample. CASE PRESENTATION: A 73-year-old woman complained of pain and swelling in the right wrist for 4 months. Her body temperature was 37-38 °C, and symptoms, such as pain, swelling, and some movement limitation, were reported. Clinical laboratory parameters showed an elevated C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), and white blood cells (WBC) count. The sequences of hsp65, rpoB, 16S rDNA, and sodA genes indicated very high homology to M. jacuzzii. CONCLUSION: We report a case of synovial infection caused by M. jacuzzii in a patient with severe wrist pain in Iran, who was treated with amikacin, levofloxacin, and ethambutol. The outcomes of treatment after 8 months were positive, and no recurrence of infection was reported in the patient.


Assuntos
Implantes de Mama/efeitos adversos , Infecções por Mycobacterium/diagnóstico , Mycobacterium/genética , Membrana Sinovial/microbiologia , Idoso , Amicacina/uso terapêutico , Antibacterianos/uso terapêutico , Sedimentação Sanguínea , Feminino , Humanos , Irã (Geográfico) , Contagem de Leucócitos , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/tratamento farmacológico , Infecções por Mycobacterium/microbiologia , Filogenia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/metabolismo , Punho/microbiologia
2.
PLoS One ; 15(8): e0236796, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780734

RESUMO

It is well-known that different plant species, and even plant varieties, promote different assemblages of the microbial communities associated with them. Here, we investigate how microbial communities (bacteria and fungi) undergo changes within the influence of woody plants (two olive cultivars, one tolerant and another susceptible to the soilborne fungal pathogen Verticillium dahliae, plus wild Holm oak) grown in the same soil but with different management (agricultural versus native). By the use of metabarcoding sequencing we determined that the native Holm oak trees rhizosphere bacterial communities were different from its bulk soil, with differences in some genera like Gp4, Gp6 and Solirubrobacter. Moreover, the agricultural management used in the olive orchard led to belowground microbiota differences with respect to the natural conditions both in bulk soils and rhizospheres. Indeed, Gemmatimonas and Fusarium were more abundant in olive orchard soils. However, agricultural management removed the differences in the microbial communities between the two olive cultivars, and these differences were minor respect to the olive bulk soil. According to our results, and at least under the agronomical conditions here examined, the composition and structure of the rhizospheric microbial communities do not seem to play a major role in olive tolerance to V. dahliae.


Assuntos
Microbiota/genética , Olea/microbiologia , Quercus/microbiologia , Microbiologia do Solo , DNA Fúngico/química , DNA Fúngico/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Raízes de Plantas/microbiologia , Análise de Componente Principal , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Rizosfera , Análise de Sequência de DNA , Verticillium/genética , Verticillium/patogenicidade
3.
Nucleic Acids Res ; 48(14): 7924-7943, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32652011

RESUMO

Biogenesis of mammalian mitochondrial ribosomes (mitoribosomes) involves several conserved small GTPases. Here, we report that the Obg family protein GTPBP5 or MTG2 is a mitochondrial protein whose absence in a TALEN-induced HEK293T knockout (KO) cell line leads to severely decreased levels of the 55S monosome and attenuated mitochondrial protein synthesis. We show that a fraction of GTPBP5 co-sediments with the large mitoribosome subunit (mtLSU), and crosslinks specifically with the 16S rRNA, and several mtLSU proteins and assembly factors. Notably, the latter group includes MTERF4, involved in monosome assembly, and MRM2, the methyltransferase that catalyzes the modification of the 16S mt-rRNA A-loop U1369 residue. The GTPBP5 interaction with MRM2 was also detected using the proximity-dependent biotinylation (BioID) assay. In GTPBP5-KO mitochondria, the mtLSU lacks bL36m, accumulates an excess of the assembly factors MTG1, GTPBP10, MALSU1 and MTERF4, and contains hypomethylated 16S rRNA. We propose that GTPBP5 primarily fuels proper mtLSU maturation by securing efficient methylation of two 16S rRNA residues, and ultimately serves to coordinate subunit joining through the release of late-stage mtLSU assembly factors. In this way, GTPBP5 provides an ultimate quality control checkpoint function during mtLSU assembly that minimizes premature subunit joining to ensure the assembly of the mature 55S monosome.


Assuntos
Proteínas Mitocondriais/metabolismo , Ribossomos Mitocondriais/enzimologia , Proteínas Monoméricas de Ligação ao GTP/metabolismo , RNA Ribossômico 16S/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/enzimologia , Linhagem Celular , GTP Fosfo-Hidrolases/metabolismo , Células HEK293 , Humanos , Metilação , Metiltransferases/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/fisiologia , Ribossomos Mitocondriais/metabolismo , Proteínas Monoméricas de Ligação ao GTP/fisiologia , Fosforilação Oxidativa , Biossíntese de Proteínas , RNA Ribossômico 16S/química , Subunidades Ribossômicas Maiores de Eucariotos/química , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo , Fatores de Transcrição/metabolismo
4.
PLoS One ; 15(7): e0218636, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32639969

RESUMO

Microbial colonization of bone is an important mechanism of postmortem skeletal degradation. However, the types and distributions of bone and tooth colonizing microbes are not well characterized. It is unknown if microbial communities vary in abundance or composition between bone element types, which could help explain differences in human DNA preservation. The goals of the present study were to (1) identify the types of microbes capable of colonizing different human bone types and (2) relate microbial abundances, diversity, and community composition to bone type and human DNA preservation. DNA extracts from 165 bone and tooth samples from three skeletonized individuals were assessed for bacterial loading and microbial community composition and structure. Random forest models were applied to predict operational taxonomic units (OTUs) associated with human DNA concentration. Dominant bacterial bone colonizers were from the phyla Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, and Planctomycetes. Eukaryotic bone colonizers were from Ascomycota, Apicomplexa, Annelida, Basidiomycota, and Ciliophora. Bacterial loading was not a significant predictor of human DNA concentration in two out of three individuals. Random forest models were minimally successful in identifying microbes related to human DNA concentration, which were complicated by high variability in community structure between individuals and body regions. This work expands on our understanding of the types of microbes capable of colonizing the postmortem human skeleton and potentially contributing to human skeletal DNA degradation.


Assuntos
Osso e Ossos/microbiologia , Microbiota , Antropologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Autopsia , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , DNA/química , DNA/metabolismo , Humanos , Masculino , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Dente/microbiologia
5.
PLoS One ; 15(7): e0235560, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614907

RESUMO

The present study investigated the effects of four woody forages (Moringa oleifera Lam (MOL), fermented MOL, Folium mori (FM) and fermented FM) on biodiversity and bioactivity of aerobic culturable gut bacteria of tilapia (Oreochromis niloticus) by a traditional culture-dependent method. A total of 133 aerobic culturable isolates were recovered and identified from the gut of tilapia, belonging to 35 species of 12 genera in three bacterial phyla (Firmicutes, Actinobacteria and Proteobacteria). Among them, 6 bacterial isolates of Bacillus baekryungensis, Bacillus marisflavi, Bacillus pumilus, Bacillus methylotrophicus, Proteus mirabilis and Pseudomonas taiwanensis were isolated from all the five experimental groups. The Bray-Curtis analysis showed that the bacterial communities among the five groups displayed obvious differences. In addition, this result of bioactivity showed that approximate 43% of the aerobic culturable gut bacteria of tilapia displayed a distinct anti-bacterial activity against at least one of four fish pathogens Streptococcus agalactiae, Streptococcus iniae, Micrococcus luteus and Vibrio parahemolyticus. Furthermore, Bacillus amyloliquefaciens and Streptomyces rutgersensis displayed strong activity against all four indicator bacteria. These results contribute to our understanding of the intestinal bacterial diversity of tilapia when fed with woody forages and how certain antimicrobial bacteria flourished under such diets. This can aid in the further exploitation of new diets and probiotic sources in aquaculture.


Assuntos
Bactérias/isolamento & purificação , Ciclídeos/microbiologia , Microbioma Gastrointestinal , Aerobiose , Animais , Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Bacillus/genética , Bacillus/isolamento & purificação , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Biodiversidade , Dieta/veterinária , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/microbiologia , Testes de Sensibilidade Microbiana , Filogenia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/metabolismo , Streptococcus/efeitos dos fármacos , Streptococcus/genética , Streptococcus/isolamento & purificação
6.
PLoS One ; 15(7): e0235537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614926

RESUMO

Recent studies describe the use of UAVs in collecting blow samples from large whales to analyze the microbial and viral community in exhaled air. Unfortunately, attempts to collect blow from small cetaceans have not been successful due to their swimming and diving behavior. In order to overcome these limitations, in this study we investigated the application of a specific sampling tool attached to a UAV to analyze the blow from small cetaceans and their respiratory microbiome. Preliminary trials to set up the sampling tool were conducted on a group of 6 bottlenose dolphins (Tursiops truncatus) under human care, housed at Acquario di Genova, with approximately 1 meter distance between the blowing animal and the tool to obtain suitable samples. The same sampling kit, suspended via a 2 meter rope assembled on a waterproof UAV, flying 3 meters above the animals, was used to sample the blows of 5 wild bottlenose dolphins in the Gulf of Ambracia (Greece) and a sperm whale (Physeter macrocephalus) in the southern Tyrrhenian Sea (Italy), to investigate whether this experimental assembly also works for large whale sampling. In order to distinguish between blow-associated microbes and seawater microbes, we pooled 5 seawater samples from the same area where blow samples' collection were carried out. The the respiratory microbiota was assessed by using the V3-V4 region of the 16S rRNA gene via Illumina Amplicon Sequencing. The pooled water samples contained more bacterial taxa than the blow samples of both wild animals and the sequenced dolphin maintained under human care. The composition of the bacterial community differed between the water samples and between the blow samples of wild cetaceans and that under human care, but these differences may have been mediated by different microbial communities between seawater and aquarium water. The sperm whale's respiratory microbiome was more similar to the results obtained from wild bottlenose dolphins. Although the number of samples used in this study was limited and sampling and analyses were impaired by several limitations, the results are rather encouraging, as shown by the evident microbial differences between seawater and blow samples, confirmed also by the meta-analysis carried out comparing our results with those obtained in previous studies. Collecting exhaled air from small cetaceans using drones is a challenging process, both logistically and technically. The success in obtaining samples from small cetacean blow in this study in comparison to previous studies is likely due to the distance the sampling kit is suspended from the drone, which reduced the likelihood that the turbulence of the drone propeller interfered with successfully sampling blow, suggested as a factor leading to poor success in previous studies.


Assuntos
Cetáceos/microbiologia , Microbiota , Sistema Respiratório/microbiologia , Aeronaves , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Golfinho Nariz-de-Garrafa/microbiologia , Análise por Conglomerados , Análise de Componente Principal , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Robótica , Baleias/microbiologia
7.
Food Chem ; 332: 127389, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32645674

RESUMO

Food allergens that cause anaphylactic reactions have become an important health problem worldwide. Among them, shrimp is a popular seafood in many cuisines. The best way to avoid allergic reactions is to mitigate the intake of food allergens. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed for the detection of shrimp DNA. Using LAMP primers, the identification of shrimp DNA by the LAMP assay was specific and rapid (within 30 min). It exhibited no cross-reaction with the DNA of other Crustacea, including crabs and lobster, and at least 0.01% shrimp DNA existed in the test sample. Additionally, the sensitivity of LAMP for detecting shrimp DNA was 100-fold greater than that of conventional PCR. LAMP for the detection of shrimp DNA was reproducible regardless of whether the genomic DNA was extracted from boiled, steamed or roasted shrimp samples. In summary, the LAMP assay established herein not only could be potentially used for diagnosing shrimp DNA but could also be applicable for identifying shrimp allergens in commercial food products in marketplaces.


Assuntos
Alérgenos/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Penaeidae/genética , Alimentos Marinhos/análise , Alérgenos/genética , Animais , Sequência de Bases , Braquiúros/genética , Primers do DNA/metabolismo , Nephropidae/genética , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Alinhamento de Sequência
8.
PLoS One ; 15(7): e0235661, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32702038

RESUMO

As urban areas expand around the world, there are growing efforts to restore and protect natural and agricultural systems for the multitude of ecosystem services they provide to urban communities. This study presents a researcher-farmer collaboration in a highly urbanized area of O'ahu focused on understanding the historical and current challenges and opportunities faced by a culturally and socially valued spring-dependent urban farm, Sumida Farm, which produces the majority of the state of Hawai'i's watercress. We conducted a long-term trend analysis (25 years) of factors identified by the farmers to be important historical drivers of crop yield, including groundwater pumping, pest outbreaks, temperature, Oceanic Niño Index, and precipitation. We combined this analysis with a year of intensive spring water sampling on the farm to evaluate nutrient and contaminant composition and flow to understand water-related stressors, as well as evaluate the potential of the farm to provide nutrient retention services. We found negative correlations between historical crop yields and increases in the Oceanic Niño Index, temperature thresholds, and pest outbreaks. Despite the surrounding urbanization, we found on-farm water quality to be very high, and microbial analyses revealed an abundance of denitrifiers (nirS gene) suggesting that the farm provides a nutrient retention service to downstream systems. Finally, we found that socio-cultural values including heritage value, aesthetic value, and educational value are increasingly important for the Sumida family and surrounding community. These socio-cultural benefits alongside highly valued local food production and nutrient retention services are essential for continued community and political support. Collectively, our study demonstrates that challenges facing urban agricultural systems shift through time, and that recognition of the beyond crop-yield benefits of these systems to urban communities is essential to their long-term survival.


Assuntos
Agricultura , Brassicaceae/crescimento & desenvolvimento , Bactérias/genética , Bactérias/isolamento & purificação , Produção Agrícola , Ecossistema , Fazendas , Hawaii , Ciclo do Nitrogênio , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Microbiologia do Solo , Urbanização , Qualidade da Água
9.
PLoS One ; 15(7): e0236595, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706816

RESUMO

Colorectal cancer (CRC) risk is influenced by host genetics, sex, and the gut microbiota. Using a genetically susceptible mouse model of CRC induced via inoculation with pathobiont Helicobacter spp. and demonstrating variable tumor incidence, we tested the ability of the Th17-enhancing commensal Candidatus Savagella, more commonly denoted as Segmented Filamentous Bacteria (SFB), to influence the incidence and severity of colitis-associated CRC in male and female mice. To document the composition of the gut microbiota during CRC development and identify taxa associated with disease, fecal samples were collected before and throughout disease development and characterized via 16S rRNA sequencing. While there were no significant SFB-dependent effects on disease incidence or severity, SFB was found to exert a sex-dependent protective effect in male mice. Furthermore, SFB stabilized the GM against Helicobacter-induced changes post-inoculation, resulting in a shift in disease association from Helicobacter spp. to Escherichia coli. These data support sex-dependent SFB-mediated effects on CRC risk, and highlight the complex community dynamics within the GM during exposure to inflammatory pathobionts.


Assuntos
Clostridiaceae/patogenicidade , Colite/patologia , Neoplasias Colorretais/patologia , Animais , Clostridiaceae/genética , Colite/complicações , Neoplasias Colorretais/etiologia , Modelos Animais de Doenças , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal , Helicobacter/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Estadiamento de Neoplasias , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Proteína Smad3/deficiência , Proteína Smad3/genética
10.
PLoS One ; 15(6): e0234127, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492060

RESUMO

Several studies have shown the ubiquitous presence of bacteria in hospital surfaces, staff, and patients. Frequently, these bacteria are related to HAI (healthcare-associated infections) and carry antimicrobial resistance (AMR). These HAI-related bacteria contribute to a major public health issue by increasing patient morbidity and mortality during or after hospital stay. Bacterial high-throughput amplicon gene sequencing along with identification of AMR genes, as well as whole genome sequencing (WGS), are biotechnological tools that allow multiple-sample screening for a diversity of bacteria. In this paper, we used these methods to perform a one-year cross sectional profiling of bacteria and AMR genes in adult and neonatal intensive care units (ICU and NICU) in a Brazilian public, tertiary hospital. Our results showed high abundances of HAI-related bacteria such as S. epidermidis, S. aureus, K. pneumoniae, A. baumannii complex, E. coli, E. faecalis, and P. aeruginosa in patients and hospital surfaces. Most abundant AMR genes detected throughout ICU and NICU were mecA, blaCTX-M-1 group, blaSHV-like, and blaKPC-like. We found that NICU environment and patients were more widely contaminated with pathogenic bacteria than ICU. Patient samples, despite the higher bacterial load, have lower bacterial diversity than environmental samples in both units. Finally, we also identified contamination hotspots in the hospital environment showing constant frequencies of bacterial and AMR contamination throughout the year. Whole genome sequencing (WGS), 16S rRNA oligotypes, and AMR identification allowed a high-resolution characterization of the hospital microbiome profile.


Assuntos
Bactérias/genética , Farmacorresistência Bacteriana/genética , Adulto , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Carga Bacteriana , Brasil , Infecção Hospitalar/microbiologia , Infecção Hospitalar/patologia , Estudos Transversais , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Recém-Nascido , Unidades de Terapia Intensiva , Unidades de Terapia Intensiva Neonatal , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Centros de Atenção Terciária , Sequenciamento Completo do Genoma
11.
Food Chem ; 329: 127179, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32505987

RESUMO

The prebiotic activities of hydrolyzed guar gum (GMOS, <1 kDa; GMPS, 1-10 kDa), manno-oligosaccharide (MOS, <1 kDa), and galacto-oligosaccharide (GOS, <1 kDa) were evaluated by in vitro fermentation. The tested carbohydrates showed selective prebiotic effects on bacterial growth, short-chain fatty acid (SCFA)-production, and substrate consumption. GOS and GMOS markedly promoted the growth of bifidobacteria and Clostridium butyricum, respectively, whereas MOS showed the strongest butyrogenic effect. Moreover, SCFA production in the hydrolyzed guar gum groups was closely related to the varied molecular weight (Mw) of the hydrolysate. During in vitro fermentation with human fecal inocula, GMOS gave the highest yields of lactate, propionate, and butyrate after 48 h fermentation. Combined application of MOS and C. butyricum increased the abundance of Clostridiaceae_1. Overall, our results indicate that galactosyl and mannosyl carbohydrates have individualized prebiotic effects which are associated with their chemical structures including their glycoside composition and Mw.


Assuntos
Oligossacarídeos/análise , Prebióticos/análise , Técnicas de Cultura Celular por Lotes , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/genética , Bifidobacterium/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Clostridium butyricum/efeitos dos fármacos , Clostridium butyricum/genética , Clostridium butyricum/crescimento & desenvolvimento , Ácidos Graxos Voláteis/química , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Galactanos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Mananas/metabolismo , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Gomas Vegetais/metabolismo , RNA Ribossômico 16S/química , RNA Ribossômico 16S/metabolismo
12.
Chemosphere ; 255: 126833, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32387724

RESUMO

Understanding the transformation pattern of nitrogen (N) pollutants and its pathways in the prechlorinated raw water distribution system (PRWDS) is vital for controlling the stablitiy and safety of raw water qulity. This study investigated the N transformation, N functional genes and their correlations to find the N transformation pathways along the PRWDS. Results suggested that simultaneous nitrification, anaerobic ammonium oxidation and denitrification (SNAD) contribute to the N transformationin the PRWDS. Along the pipeline, anammox 16S rRNA (9.18 × 107-8.41 × 108 copies/g), limited by prechlorination, was the most abundant N functional genes and anammox process was the main pathway of ammonia nitrogen (NH4+-N). The decreasing NH4+-N was connected with Planctomycetes, Nitrospira and abundance of nxrA attributing to the joint effort of anammox and declined nitrification. The concentration of nitrate (NO3--N) increasing at first and then decreasing, was correlated positively with Sphingomonas. because of the declined nitritication and increased denitrification. Besides, the NO3--N→NO2--N process was considered to be primary NO3--N transformation pathways. Increases in the concentration of dissolved organic nitrogen (DON) and nitrite (NO2--N) observed in the PRWDS had positive correlation with relative abundance of Pseudomonas. We believe that prechlorination shaped the particular bacterialcharacteristics in biofilms and influenced the N transformation pathways indirectly, resulting in the varying N transformation rules in PRWDSs. Moreover, systematic and extended research is particularly vital for determining the effects of changes in source water quality and environmental conditions on bacterial community structure and N conversion along PRWDSs.


Assuntos
Nitrogênio/análise , Poluentes da Água/análise , Abastecimento de Água/estatística & dados numéricos , Amônia/metabolismo , Bactérias/metabolismo , Biofilmes , Reatores Biológicos/microbiologia , Desnitrificação , Poluentes Ambientais/metabolismo , Nitratos/metabolismo , Nitrificação , Nitritos/análise , Oxirredução , RNA Ribossômico 16S/metabolismo
13.
Nat Commun ; 11(1): 2168, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358520

RESUMO

Gut microbiota composition influences the clinical benefit of immune checkpoints in patients with advanced cancer but mechanisms underlying this relationship remain unclear. Molecular mechanism whereby gut microbiota influences immune responses is mainly assigned to gut microbial metabolites. Short-chain fatty acids (SCFA) are produced in large amounts in the colon through bacterial fermentation of dietary fiber. We evaluate in mice and in patients treated with anti-CTLA-4 blocking mAbs whether SCFA levels is related to clinical outcome. High blood butyrate and propionate levels are associated with resistance to CTLA-4 blockade and higher proportion of Treg cells. In mice, butyrate restrains anti-CTLA-4-induced up-regulation of CD80/CD86 on dendritic cells and ICOS on T cells, accumulation of tumor-specific T cells and memory T cells. In patients, high blood butyrate levels moderate ipilimumab-induced accumulation of memory and ICOS + CD4 + T cells and IL-2 impregnation. Altogether, these results suggest that SCFA limits anti-CTLA-4 activity.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/metabolismo , Ácidos Graxos Voláteis/sangue , Neoplasias/sangue , Neoplasias/metabolismo , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Biomarcadores Tumorais/metabolismo , Butiratos/sangue , Células Dendríticas/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Humanos , Ipilimumab/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Propionatos/sangue , RNA Ribossômico 16S/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo
14.
PLoS One ; 15(4): e0231426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271848

RESUMO

Demand for agricultural crop continues to escalate in response to increasing population and damage of prime cropland for cultivation. Research interest is diverted to utilize soils with marginal plant production. Moisture stress has negative impact on crop growth and productivity. The plant growth promoting rhizobacteria (PGPR) and plant growth regulators (PGR) are vital for plant developmental process under moisture stress. The current study was carried out to investigate the effect of PGPR and PGRs (Salicylic acid and Putrescine) on the physiological activities of chickpea grown in sandy soil. The bacterial isolates were characterized based on biochemical characters including Gram-staining, P-solubilisation, antibacterial and antifungal activities and catalases and oxidases activities and were also screened for the production of indole-3-acetic acid (IAA), hydrogen cyanide (HCN) and ammonia (NH3). The bacterial strains were identified as Bacillus subtilis, Bacillus thuringiensis and Bacillus megaterium based on the results of 16S-rRNA gene sequencing. Chickpea seeds of two varieties (Punjab Noor-2009 and 93127) differing in sensitivity to drought were soaked for 3 h before sowing in fresh grown cultures of isolates. Both the PGRs were applied (150 mg/L), as foliar spray on 20 days old seedlings of chickpea. Moisture stress significantly reduced the physiological parameters but the inoculation of PGPR and PGR treatment effectively ameliorated the adverse effects of moisture stress. The result showed that chickpea plants treated with PGPR and PGR significantly enhanced the chlorophyll, protein and sugar contents. Shoot and root fresh (81%) and dry weights (77%) were also enhanced significantly in the treated plants. Leaf proline content, lipid peroxidation and antioxidant enzymes (CAT, APOX, POD and SOD) were increased in reaction to drought stress but decreased due to PGPR. The plant height (61%), grain weight (41%), number of nodules (78%) and pod (88%), plant yield (76%), pod weight (53%) and total biomass (54%) were higher in PGPR and PGR treated chickpea plants grown in sandy soil. It is concluded from the present study that the integrative use of PGPR and PGRs is a promising method and eco-friendly strategy for increasing drought tolerance in crop plants.


Assuntos
Agricultura , Bacillaceae/fisiologia , Cicer/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/farmacologia , Amônia/metabolismo , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Bacillus megaterium/genética , Bacillus megaterium/isolamento & purificação , Bacillus subtilis/genética , Bacillus subtilis/isolamento & purificação , Bacillus subtilis/fisiologia , Biomassa , Clorofila/análise , Cicer/efeitos dos fármacos , Cicer/metabolismo , Ácidos Indolacéticos/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Putrescina/metabolismo , Putrescina/farmacologia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/metabolismo , Chuva , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Microbiologia do Solo
15.
PLoS One ; 15(4): e0231942, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32339193

RESUMO

Salmonella enterica serovar Typhimurium is an animal welfare and public health concern due to its ability to parasite livestock and potentially contaminate pork products. To reduce Salmonella shedding and the risk of pork contamination, antibiotic therapy is used and can contribute to antimicrobial resistance. Here we hypothesized that immune system education by the microbiota can play a role in intestinal resilience to infection. We used amoxicillin (15mg/Kg) to modulate the intestinal microbiome of 10 piglets, paired with same age pigs that received a placebo (n = 10) from 0 to 14 days of age. Animals were euthanized at 4-weeks old. Each pig donated colon sections for ex vivo culture (n = 20 explants/pig). Explants were inoculated with S. Typhimurium, PBS or LPS (n = 6 explants/pig/group, plus technical controls). The gut bacteriome was characterized by sequencing of the 16S rRNA at 7, 21 days of age, and upon in vitro culture. Explants response to infection was profiled through high-throughput mRNA sequencing. In vivo antibiotic treatment led to ß-diversity differences between groups at all times (P<0.05), while α-diversity did not differ between amoxicillin and placebo groups on day 21 and at euthanasia (P<0.03 on day 7). Explant microbiomes were not different from in vivo. In vitro challenge with S. Typhimurium led to lower necrosis scores in explants from amoxicillin-treated pigs, when compared to explants placebo-treated pigs (P<0.05). This was coupled with the activation of immune-related pathways in explants from amoxicillin-treated pigs (IL-2 production, NO production, BCR activation), when compared to placebo-treated pigs. In addition, several DNA repair and intestinal wound healing pathways were also only activated in explants from amoxicillin-treated pigs. Taken together, these findings suggest that immune education by the amoxicillin-disturbed microbiota may have contributed to mitigate intestinal lesions following pathogen exposure.


Assuntos
Antibacterianos/farmacologia , Epigênese Genética/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Salmonella typhimurium/patogenicidade , Amoxicilina/farmacologia , Animais , Animais Recém-Nascidos , Bactérias/genética , Bactérias/isolamento & purificação , Colo/citologia , Colo/microbiologia , Colo/patologia , Regulação para Baixo/efeitos dos fármacos , Fezes/microbiologia , Análise de Componente Principal , RNA Ribossômico 16S/química , RNA Ribossômico 16S/metabolismo , Salmonelose Animal/imunologia , Suínos , Doenças dos Suínos/imunologia , Regulação para Cima/efeitos dos fármacos
16.
Nucleic Acids Res ; 48(10): 5616-5623, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32343306

RESUMO

Bacterial ribosomal RNAs (rRNAs) are transcribed as precursors and require processing by Ribonucleases (RNases) to generate mature and functional rRNAs. Although the initial steps of rRNA processing in Escherichia coli (E. coli) were described several decades ago, the enzymes responsible for the final steps of 5S and 23S rRNA 5'-end maturation have remained unknown. Here, I show that RNase AM, a recently identified 5' to 3' exonuclease, performs the last step of 5S rRNA 5'-end maturation. RNase AM was also found to generate the mature 5' end of 23S rRNA, subsequent to a newly identified prior processing step. Additionally, RNase AM was found to mature the 5' end of 16S rRNA, a reaction previously attributed to RNase G. These findings indicate a major role for RNase AM in cellular RNA metabolism and establish a biological role for the first 5' to 3' RNA exonuclease identified in E. coli.


Assuntos
Escherichia coli/enzimologia , Exorribonucleases/metabolismo , Processamento Pós-Transcricional do RNA , RNA Ribossômico 16S/metabolismo , RNA Ribossômico 23S/metabolismo , RNA Ribossômico 5S/metabolismo , Escherichia coli/genética
17.
Nat Commun ; 11(1): 1922, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321922

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease in which insulin-producing pancreatic ß-cells are destroyed. Intestinal helminths can cause asymptomatic chronic and immunosuppressive infections and suppress disease in rodent models of T1D. However, the underlying regulatory mechanisms for this protection are unclear. Here, we report that CD8+ regulatory T (Treg) cells prevent the onset of streptozotocin -induced diabetes by a rodent intestinal nematode. Trehalose derived from nematodes affects the intestinal microbiota and increases the abundance of Ruminococcus spp., resulting in the induction of CD8+ Treg cells. Furthermore, trehalose has therapeutic effects on both streptozotocin-induced diabetes and in the NOD mouse model of T1D. In addition, compared with healthy volunteers, patients with T1D have fewer CD8+ Treg cells, and the abundance of intestinal Ruminococcus positively correlates with the number of CD8+ Treg cells in humans.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Linfócitos T Reguladores/imunologia , Animais , Clostridiales , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Modelos Animais de Doenças , Faecalibacterium prausnitzii , Feminino , Microbioma Gastrointestinal , Humanos , Imunossupressores , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , RNA Ribossômico 16S/metabolismo , Ruminococcus , Trealose/farmacologia
18.
PLoS One ; 15(4): e0231222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32251446

RESUMO

IL-17A and IL-17F cytokines are important regulators of acute graft-versus-host-disease (GVHD). However, contrary effects of these cytokines in inflammatory diseases have been reported. To investigate the effects of donor-derived IL-17A and IL-17F on GVHD, we made use of single (Il17a-/- or Il17f-/-) and double deficient (Il17af-/-) allogeneic donor CD4+ T cells. We could demonstrate that transplantation of Il17af-/- CD4+ donor T cells led to aggravated GVHD. However, this phenotype was not observed after transplantation of single, Il17a-/- or Il17f-/-, deficient CD4+ T cells, suggesting redundant effects of IL-17A and IL-17F. Moreover, Il17af-/- cell recipients showed an increase of systemic IFNγ, indicating a heightened pro-inflammatory state, as well as infiltration of IFNγ-secreting CD4+ T cells in the recipients' intestinal tract. These recipients exhibited significant gut leakage, and markedly macrophage infiltration in the gastrointestinal epithelial layer. Moreover, we saw evidence of impaired recovery of gut epithelial cells in recipients of Il17af-/- CD4+ T cells. In this study, we show that IL-17A/F double deficiency of donor CD4+ T cells leads to accelerated GVHD and therefore highlight the importance of these cytokines. Together, IL-17 cytokines might serve as a brake to an intensified Th1 response, leading to the exacerbated gut damage in acute GVHD.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Interleucina-17/metabolismo , Intestinos/imunologia , Células Th1/citologia , Animais , Transplante de Medula Óssea , Linfócitos T CD4-Positivos/citologia , Células CACO-2 , Proliferação de Células , Microbioma Gastrointestinal , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Macrófagos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , RNA Ribossômico 16S/metabolismo
19.
Mol Biotechnol ; 62(6-7): 326-334, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32227298

RESUMO

The study of translation initiation in prokaryotes assumes that there should be a mechanism different from the canonical model, which postulates the formation of the pre-initiation complex through the interaction of the Shine-Dalgarno sequence (SD) at the 5'-end of mRNA and the anti-Shine-Dalgarno site at the 3'-end of 16S rRNA. In this paper we've studied the effect of TPS (Translation-initiation Promoting Site) on ß-glucuronidase expression in E. coli cells at different cultivation temperatures. The examined leader sequences were cloned into the pET23c plasmid upstream the ß-glucuronidase gene; protein expression was performed in E. coli BL21 (DE3) cells. ß-glucuronidase activity was measured in bacterial cell extracts via paranitrophenyl b-D-glucuronide assay. The quantity of expressed protein was measured by Western blotting with following densitometry. It was shown that TPS increases the level of protein expression at stressful conditions (10 °C and 44 °C) 5-8 times compared to control. The combination of TPS and SD sites in the 5'-leader sequence of the mRNA created an enhancer that increased the expression level 2-3.6 times compared to a single SD-sequence. Based on the obtained data and the computer modeling of interaction between 16S rRNA and TPS, we proposed an alternative variation of prokaryotic translation initiation.


Assuntos
Escherichia coli/metabolismo , Regiões 5' não Traduzidas/genética , Regiões 5' não Traduzidas/fisiologia , Escherichia coli/genética , Biossíntese de Proteínas , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
20.
BMC Infect Dis ; 20(1): 199, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143636

RESUMO

BACKGROUND: Campylobacter jejuni is a motile, gram-negative rod known for causing self-limiting enterocolitis while rarely causing extraintestinal infections. We report the first case of a patient with Campylobacter jejuni osteomyelitis in both femora. CASE PRESENTATION: A 54-year-old female presented with progressive pain in both upper extremities. Her past medical history mentioned a lymphoplasmacytic lymphoma (LPL) for which she had received dexamethasone, cyclophosphamide and fludarabine and was still receiving maintenance therapy with intravenous rituximab. Two months prior to presentation, she received oral fluoroquinolone for a recurrent enterocolitis with stool cultures positive for Campylobacter jejuni. Palpation of the left quadriceps femoris muscle was remarkably painful during physical examination. Laboratory testing showed elevated C-reactive protein and recent low gamma globulin levels. The presumptive diagnosis at this point was a transformation of LPL to a large B cell lymphoma. In order to determine the preferred site for biopsy, a fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography was done. However, blood cultures taken on admission showed growth of Campylobacter jejuni in both aerobic bottles, with a strain resistant to fluoroquinolones. Diagnosis of Campylobacter jejuni osteomyelitis was confirmed with 16S ribosomal RNA gene polymerase chain reaction performed on femoral bone obtained through biopsy. Treatment with intravenous imipenem/cilastatin followed by intravenous and oral doxycycline proved insufficient. Subsequently, the patient was treated successfully with intravenous meropenem for six weeks and concurrent intravenous immunoglobulin. CONCLUSION: We report the first case of Campylobacter jejuni osteomyelitis in both femora in a patient with acquired hypogammaglobulinemia. Diagnosis was confirmed by blood cultures and positive 16S ribosomal RNA gene polymerase chain reaction for Campylobacter spp. on bone biopsy. Treatment was successful with intravenous meropenem and immunoglobulin. Our report showcases an unusual manifestation in a patient with immunodeficiency and discusses failure of initial antibiotic therapy.


Assuntos
Infecções por Campylobacter/diagnóstico , Imunodeficiência de Variável Comum/diagnóstico , Osteomielite/diagnóstico , Antibacterianos/uso terapêutico , Proteína C-Reativa/análise , Infecções por Campylobacter/complicações , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Imunodeficiência de Variável Comum/complicações , Doxiciclina/uso terapêutico , Feminino , Fêmur/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Osteomielite/complicações , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
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