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1.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474041

RESUMO

Dickeya solani, belonging to the Soft Rot Pectobacteriaceae, are aggressive necrotrophs, exhibiting both a wide geographic distribution and a wide host range that includes many angiosperm orders, both dicot and monocot plants, cultivated under all climatic conditions. Little is known about the infection strategies D. solani employs to infect hosts other than potato (Solanum tuberosum L.). Our earlier study identified D. solani Tn5 mutants induced exclusively by the presence of the weed host S. dulcamara. The current study assessed the identity and virulence contribution of the selected genes mutated by the Tn5 insertions and induced by the presence of S. dulcamara. These genes encode proteins with functions linked to polyketide antibiotics and polysaccharide synthesis, membrane transport, stress response, and sugar and amino acid metabolism. Eight of these genes, encoding UvrY (GacA), tRNA guanosine transglycosylase Tgt, LPS-related WbeA, capsular biosynthesis protein VpsM, DltB alanine export protein, glycosyltransferase, putative transcription regulator YheO/PAS domain-containing protein, and a hypothetical protein, were required for virulence on S. dulcamara plants. The implications of D. solani interaction with a weed host, S. dulcamara, are discussed.


Assuntos
Solanum tuberosum , Solanum , Solanum/genética , Dickeya/genética , Solanum tuberosum/genética , Enterobacteriaceae/genética , Loci Gênicos , Doenças das Plantas
2.
BMJ Paediatr Open ; 7(1)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37192777

RESUMO

BACKGROUND: Hospital-acquired strains (HASs) and multiresistant strains in neonatal intensive care unit often harbour virulence and resistance mechanisms, carrying the risk of invasive infections. We describe colonisation with Enterobacteriaceae in neonates receiving early directed versus routine family-integrated care (FIC) within the first month of life. METHODS: A prospective cohort study included neonates with a gestational age below 34 weeks. During the first period, neonates were admitted to an open bay unit with transfer to the single-family room if available; feeding with the mother's own breast milk (MOBM) was introduced within 24 hours, and skin-to-skin contact (SSC) within 5 days of life (the routine care group). During the second period, following a wash-in of 2 months, care in a single-family room within 48 hours, the introduction of MOBM within two and SSC in 48 hours were applied (the intervention group). Enterobacteriaceae isolated from neonatal stool, breast milk and parental skin swabs were genotyped, Simpson's Index of Diversity (SID) calculated, and extended-spectrum beta-lactamases (ESBL) detected. RESULTS: In 64 neonate-parents' groups, 176 Enterobacteriaceae, 87 in routine care and 89 in the intervention group were isolated; 26 vs 18 were HAS and one vs three ESBL positive, respectively. In the intervention group compared with the routine care group, SSC and MOBM feeding was started significantly earlier (p<0.001); during the first week of life, time spent in SSC was longer (median hours per day 4.8 (4-5.1) vs 1.9 (1.4-2.6), p<0.001) and the proportion of MOBM in enteral feeds was higher (median (IQR) 97.8% (95.1-100) vs 95.1% (87.2-97.4), p=0.011). Compared with the routine care group, the intervention group had higher SID and a reduction of HAS by 33.1% (95% CI 24.4% to 42.4%) in time series analysis. CONCLUSIONS: Early implementation of FIC measures may hold the potential to increase diversity and reduce colonisation with HAS Enterobacteriaceae.


Assuntos
Prestação Integrada de Cuidados de Saúde , Infecções por Enterobacteriaceae , Recém-Nascido , Feminino , Humanos , Lactente , Enterobacteriaceae/genética , Unidades de Terapia Intensiva Neonatal , Estudos Prospectivos , Infecções por Enterobacteriaceae/terapia
3.
Microb Cell Fact ; 22(1): 101, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198660

RESUMO

The nanoparticles (NPs) formed by Enterococcus thailandicus, Pseudomonas putida, Marinobacter hydrocarbonoclasticus, and P. geniculate were tested against soft rot/blackleg genera. The effects of NPs recorded on bacterial DNA, proteins, and carbohydrates concentration of Pectobacterium carotovorum subsp. carotovorum, Enterobacter cloacae (soft rot), and Dickeya solani (soft rot/blackleg). Treated cells showed degradation in isolated DNA, decreased proteins and carbohydrates concentration compared with untreated cells. Using Scanning Electron Microscope (SEM), the treated cells showed collapsed and small pits in the cell wall. Using Transmission Electron Microscope (TEM), internal changes showed penetration of NPs inside the tested bacterial cells, the appearance of periplasmic space, formation of vacuoles, and condensation of cytoplasm. Disease severity ex vivo of potato tuber infected with tested genera demonstrated that NPs treatment didn't show any rotted tissue compared with untreated. The ability to uptake and accumulate FeNPs from the soil in potato (Solanum tuberosum) seedlings; Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) was used. It recorded an increase in iron content of treated potato (Solanum tuberosum) seedlings with NPs, compared with untreated. FeNPs can be used to control soft rot/blackleg diseases, instead of copper pesticides. It could be a new, approach for disease management and increase the plant's nutritional value.


Assuntos
Pectobacterium , Solanum tuberosum , Egito , Doenças das Plantas/microbiologia , Pectobacterium/genética , Enterobacteriaceae/genética , Solanum tuberosum/microbiologia , Metais
4.
Cell Rep ; 42(2): 112102, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36774548

RESUMO

Nutritional symbionts influence host reproduction, but the underlying molecular mechanisms are largely unclear. We previously found that the bacteriocyte symbiont Hamiltonella impacts the sex ratio of the whitefly Bemisia tabaci. Hamiltonella synthesizes folate by cooperation with the whitefly. Folate deficiency by Hamiltonella elimination or whitefly gene silencing distorted whitefly sex ratio, and folate supplementation restored the sex ratio. Hamiltonella deficiency or gene silencing altered histone H3 lysine 9 trimethylation (H3K9me3) level, which was restored by folate supplementation. Genome-wide chromatin immunoprecipitation-seq analysis of H3K9me3 indicated mitochondrial dysfunction in symbiont-deficient whiteflies. Hamiltonella deficiency compromised mitochondrial quality of whitefly ovaries. Repressing ovary mitochondrial function led to distorted whitefly sex ratio. These findings indicate that the symbiont-derived folate regulates host histone methylation modifications, which thereby impacts ovary mitochondrial function, and finally determines host sex ratio. Our study suggests that a nutritional symbiont can regulate animal reproduction in a way that differs from reproductive manipulators.


Assuntos
Hemípteros , Animais , Feminino , Hemípteros/genética , Razão de Masculinidade , Simbiose/genética , Enterobacteriaceae/genética , Ácido Fólico
5.
Phytopathology ; 113(3): 390-399, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36399025

RESUMO

Nitrate metabolism plays an important role in bacterial physiology. During the interaction of plant-pathogenic bacteria with their hosts, bacteria face variable conditions with respect to nitrate availability. Perception mechanisms through the chemosensory pathway drive the entry and control the colonization of the plant host in phytopathogenic bacteria. In this work, the identification and characterization of the nitrate- and nitrite-sensing (NIT) domain-containing chemoreceptor of Dickeya dadantii 3937 (Dd3937) allowed us to unveil the key role of nitrate sensing not only for the entry into the plant apoplast through wounds but also for infection success. We determined the specificity of this chemoreceptor to bind nitrate and nitrite, with a slight ligand preference for nitrate. Gene expression analysis showed that nitrate perception controls not only the expression of nitrate reductase genes involved in respiratory and assimilatory metabolic processes but also the expression of gyrA, hrpN, and bgxA, three well-known virulence determinants in Dd3937.


Assuntos
Nitratos , Solanum tuberosum , Virulência/genética , Nitratos/metabolismo , Solanum tuberosum/microbiologia , Nitritos/metabolismo , Doenças das Plantas/microbiologia , Enterobacteriaceae/genética , Enterobacteriaceae/metabolismo , Plantas , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
6.
PLoS One ; 17(8): e0273481, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36037153

RESUMO

Dickeya solani is a soft rot bacterium with high virulence. In potato, D. solani, like the other potato-infecting soft rot bacteria, causes rotting and wilting of the stems and rotting of tubers in the field and in storage. Latent, asymptomatic infections of potato tubers are common in harvested tubers, and if the storage conditions are not optimal, the latent infection turns into active rotting. We characterized potato gene expression in artificially inoculated tubers in nonsymptomatic, early infections 1 and 24 hours post-inoculation (hpi) and compared the results to the response in symptomatic tuber tissue 1 week (168 hpi) later with RNA-Seq. In the beginning of the infection, potato tubers expressed genes involved in the detection of the bacterium through pathogen-associated molecular patterns (PAMPs), which induced genes involved in PAMPs-triggered immunity, resistance, production of pathogenesis-related proteins, ROS, secondary metabolites and salicylic acid (SA) and jasmonic acid (JA) biosynthesis and signaling genes. In the symptomatic tuber tissue one week later, the PAMPs-triggered gene expression was downregulated, whereas primary metabolism was affected, most likely leading to free sugars fueling plant defense but possibly also aiding the growth of the pathogen. In the symptomatic tubers, pectic enzymes and cell wall-based defenses were activated. Measurement of hormone production revealed increased SA concentration and almost no JA in the asymptomatic tubers at the beginning of the infection and high level of JA and reduced SA in the symptomatic tubers one week later. These findings suggest that potato tubers rely on different defense strategies in the different phases of D. solani infection even when the infection takes place in fully susceptible plants incubated in conditions leading to rotting. These results support the idea that D. solani is a biotroph rather than a true necrotroph.


Assuntos
Solanum tuberosum , Dickeya , Enterobacteriaceae/genética , Expressão Gênica , Moléculas com Motivos Associados a Patógenos , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas , Ácido Salicílico , Solanum tuberosum/microbiologia
7.
Sci Rep ; 12(1): 10725, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750797

RESUMO

Resistance to bacteriophage infections protects bacteria in phage-replete environments, enabling them to survive and multiply in the presence of their viral predators. However, such resistance may confer costs for strains, reducing their ecological fitness as expressed as competitiveness for resources or virulence or both. There is limited knowledge about such costs paid by phage-resistant plant pathogenic bacteria in their natural habitats. This study analyzed the costs of phage resistance paid by the phytopathogenic pectinolytic bacterium Dickeya solani both in vitro and in potato (Solanum tuberosum L.) plants. Thirteen Tn5 mutants of D. solani IPO 2222 were identified that exhibited resistance to infection by lytic bacteriophage vB_Dsol_D5 (ΦD5). The genes disrupted in these mutants encoded proteins involved in the synthesis of bacterial envelope components (viz. LPS, EPS and capsule). Although phage resistance did not affect most of the phenotypes of ΦD5-resistant D. solani such as growth rate, production of effectors, swimming and swarming motility, use of various carbon and nitrogen sources and biofilm formation evaluated in vitro, all phage resistant mutants were significantly compromised in their ability to survive on leaf surfaces as well as to grow within and cause disease symptoms in potato plants.


Assuntos
Bacteriófagos , Solanum tuberosum , Bacteriófagos/genética , Dickeya , Enterobacteriaceae/genética , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia
8.
Front Cell Infect Microbiol ; 12: 839257, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444955

RESUMO

Objectives: This is a comparative cohort study aiming to evaluate the mortality risk factors for patients with nosocomial meningitis (NM) induced by multidrug-resistant Enterobacteriaceae (MDRE) in China. The clinical features and therapies of patients and the resistance mechanisms of MDRE pathogens were also assessed. Methods: MDRE-NM patients from two neurosurgical centers in China from 2014 to 2019 were included in this study. Clinical features were extracted from the medical record databases of the two centers. The molecular mechanisms underlying the microbiological resistance mechanisms of each MDRE pathogen were determined, Kaplan-Meier survival analysis was conducted, and multivariable analyses were performed using a Cox proportional hazard model. Results: Ninety MDRE-NM patients were included in this study. Klebsiella pneumoniae accounted for the highest proportion of causative pathogens (46/90, 51.1%), and 40 causative pathogens (44.4%) were meropenem-resistant. blaKPC (27/40, 67.5%) was the predominant carbapenem resistance gene. Multivariate Cox analysis showed that external ventricular drainage (EVD) [hazard ratio (HR) = 2.524, 95% confidence interval (CI) = 1.101-5.787, p = 0.029] and a Glasgow Coma Scale (GCS) score ≤;8 (HR = 4.033, 95% CI = 1.526-10.645, p = 0.005) were mortality risk factors for patients with MDRE-NM. A total of 90.0%, 94.4%, and 97.8% of MDRE-NM patients received antibiotic prophylaxis (AP), antibiotic empirical therapy (AET), and antibiotic definitive therapy (ADT), respectively. Conclusions: NM caused by MDRE is an important sign of the failure of neurosurgery. MDRE possesses multiple drug resistance genotypes, and EVD and a GCS score ≤;8 are independent mortality risk factors for patients with MDRE-NM, which deserve the attention of microbiologists and neurosurgical clinicians.


Assuntos
Infecção Hospitalar , Doença pelo Vírus Ebola , Meningite , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , China/epidemiologia , Estudos de Coortes , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/genética , Humanos , Estudos Longitudinais , Testes de Sensibilidade Microbiana
9.
mBio ; 13(1): e0369121, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35073753

RESUMO

Diverse insects host specific microbial symbionts that play important roles for their growth, survival, and reproduction. They often develop specialized symbiotic organs for harboring the microbial partners. While such intimate associations tend to be stably maintained over evolutionary time, the microbial symbionts may have been lost or replaced occasionally. How symbiont acquisitions, replacements, and losses are linked to the development of the host's symbiotic organs is an important but poorly understood aspect of microbial symbioses. Cassidine leaf beetles are associated with a specific gammaproteobacterial lineage, Stammera, whose reduced genome is streamlined for producing pectin-degrading enzymes to assist the host's digestion of food plants. We investigated the symbiotic system of 24 Japanese cassidine species and found that (i) most species harbored Stammera within paired symbiotic organs located at the foregut-midgut junction, (ii) the host phylogeny was largely congruent with the symbiont phylogeny, indicating stable host-symbiont association over evolutionary time, (iii) meanwhile, the symbiont was not detected in three distinct host lineages, uncovering recurrent losses of the ancient microbial mutualist, (iv) the symbiotic organs were vestigial but present in the symbiont-free lineages, indicating evolutionary persistence of the symbiotic organs even in the absence of the symbiont, and (v) the number of the symbiotic organs was polymorphic among the cassidine species, either two or four, unveiling a dynamic evolution of the host organs for symbiosis. These findings are discussed as to what molecular mechanisms and evolutionary trajectories underpin the recurrent symbiont losses and the morphogenesis of the symbiotic organs in the herbivorous insect group. IMPORTANCE Insects represent the biodiversity of the terrestrial ecosystem, and their prosperity is attributable to their association with symbiotic microorganisms. By sequestering microbial functionality into their bodies, organs, tissues, or cells, diverse insects have successfully exploited otherwise inaccessible ecological niches and resources, including herbivory enabled by utilization of indigestible plant cell wall components. In leaf beetles of the subfamily Cassininae, an ancient symbiont lineage, Stammera, whose genome is extremely reduced and specialized for encoding pectin-degrading enzymes, is hosted in gut-associated symbiotic organs and contributes to the host's food plant digestion. Here, we demonstrate that multiple symbiont losses and recurrent structural switching of the symbiotic organs have occurred in the evolutionary course of cassidine leaf beetles, which sheds light on the evolutionary and developmental dynamics of the insect's symbiotic organs and provides a model system to investigate how microbial symbionts affect the host's development and morphogenesis and vice versa.


Assuntos
Besouros , Tartarugas , Animais , Besouros/microbiologia , Simbiose/genética , Ecossistema , Insetos/microbiologia , Filogenia , Enterobacteriaceae/genética , Pectinas
10.
J Matern Fetal Neonatal Med ; 35(7): 1405-1407, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32290751

RESUMO

BACKGROUND: Urinary tract infections (UTIs) are common in women, and during pregnancy can cause significant morbidity. Growing and greatly varying antimicrobial resistance (AMR) of Enterobacteriaceae, responsible for most UTIs, necessitates regular local AMR surveillance. In obstetric population, where beta-lactams are the mainstay for treatment of severe UTIs, particular focus should be placed on beta-lactam resistance. This study aimed to evaluate AMR rates and frequency of extended spectrum beta-lactamase (ESBL) and carbapenemase genes in uropathogenic Enterobacteriaceae among reproductive-age women in St. Petersburg, Russia. MATERIALS/METHODS: Urine samples were collected from consecutive reproductive-age women, who attended the D.O. Ott Research Institute of Obstetrics, Gynecology and Reproductology from October 2017 to November 2019, and cultured according to routine procedures. Susceptibility to antibiotics and ESBL production was determined using the disc diffusion method according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. All urine samples and Enterobacteriaceae isolates were tested for ESBL and carbapenemase genes using real-time PCR. RESULTS: Enterobacteriaceae were detected in 91 (56 pregnant and 35 non-pregnant) of 119 (76%) included women. The vast majority of Enterobacteriaceae strains were susceptible to nitrofurantoin, fosfomycin and meropenem (99-100%). The frequency of strains susceptible to penicillins and cephalosporins ranged from 59% to 82%; 78% of strains were susceptible to ciprofloxacin. ESBL production was phenotypically detected in 15 (16%) Enterobacteriaceae strains, with CTX-M genes revealed in all cases. In all corresponding urine samples, CTX-M genes were also detected. The remaining 104 urine samples were negative for CTX-M genes. In none of the isolates and urine samples, carbapenemase genes were present. CONCLUSIONS: The frequency of ESBL producing Enterobacteriaceae was relatively high (16%), with CTX-M genes detected in all cases in both urine and urine cultures. Rapid PCR detection of CTX-M genes directly in urine samples from women with pyelonephritis can be valuable for timely informing treatment choices.


Assuntos
Infecções por Enterobacteriaceae , Pielonefrite , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/tratamento farmacológico , Feminino , Humanos , Testes de Sensibilidade Microbiana , Gravidez , Pielonefrite/tratamento farmacológico , Federação Russa , beta-Lactamases/genética
12.
Mol Plant Microbe Interact ; 34(9): 1088-1092, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33861631

RESUMO

Dickeya solani is an emerging plant-pathogenic bacterium causing disease symptoms in a variety of agriculturally relevant crop species worldwide. To date, a number of D. solani genomes have been sequenced and characterized; the great majority of these genomes have, however, come from D. solani strains isolated from potato (Solanum tuberosum L.) and not from other plant hosts. Herewith, we present the first complete, high-quality genome of D. solani IPO 2019 (LMG 25990), isolated from the ornamental plant Hyacinthus orientalis. The genome of D. solani IPO 2019 consists of one chromosome of 4,919,542 bp, with a GC content of 56.2% and no plasmids. The genome contains 4,502 annotated features, 22 ribosomal RNA genes, 73 transfer RNA genes, and one CRISPR. We believe that the information on this high-quality, complete, closed genome of D. solani strain isolated from a host plant different from potato (i.e. hyacinth) will provide resources for comparative genomic studies and for analyses targeting adaptation and ecological fitness mechanisms present in Dickeya solani species.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Hyacinthus , Solanum tuberosum , Dickeya , Enterobacteriaceae/genética , Doenças das Plantas
13.
Commun Biol ; 4(1): 331, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712689

RESUMO

Multidrug-resistant (MDR) bacteria pose a grave concern to global health, which is perpetuated by a lack of new treatments and countermeasure platforms to combat outbreaks or antibiotic resistance. To address this, we have developed a Facile Accelerated Specific Therapeutic (FAST) platform that can develop effective peptide nucleic acid (PNA) therapies against MDR bacteria within a week. Our FAST platform uses a bioinformatics toolbox to design sequence-specific PNAs targeting non-traditional pathways/genes of bacteria, then performs in-situ synthesis, validation, and efficacy testing of selected PNAs. As a proof of concept, these PNAs were tested against five MDR clinical isolates: carbapenem-resistant Escherichia coli, extended-spectrum beta-lactamase Klebsiella pneumoniae, New Delhi Metallo-beta-lactamase-1 carrying Klebsiella pneumoniae, and MDR Salmonella enterica. PNAs showed significant growth inhibition for 82% of treatments, with nearly 18% of treatments leading to greater than 97% decrease. Further, these PNAs are capable of potentiating antibiotic activity in the clinical isolates despite presence of cognate resistance genes. Finally, the FAST platform offers a novel delivery approach to overcome limited transport of PNAs into mammalian cells by repurposing the bacterial Type III secretion system in conjunction with a kill switch that is effective at eliminating 99.6% of an intracellular Salmonella infection in human epithelial cells.


Assuntos
Antibacterianos/farmacologia , Biologia Computacional , Desenho de Fármacos , Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , Ácidos Nucleicos Peptídicos/farmacologia , Células 3T3 , Animais , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/genética , Enterobacteriaceae/crescimento & desenvolvimento , Infecções por Enterobacteriaceae/microbiologia , Células HeLa , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Estudo de Prova de Conceito , Células RAW 264.7
14.
FEMS Microbiol Ecol ; 97(3)2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33202005

RESUMO

This study evaluated the occurrence of extended-spectrum ß-lactamases (ESBL) and associated resistance genes, integrons, and plasmid types, as well as the genetic relatedness of enterobacterial isolates in the wastewater treatment plant (WWTP) of La Charguia, Tunis City (Tunisia). A total of 100 water samples were collected at different points of the sewage treatment process during 2017-2019. Antimicrobial susceptibility was conducted by the disc-diffusion method. blaCTX-M, blaTEM and blaSHV genes as well as those encoding non-ß-lactam resistance, the plasmid types, occurrence of class1 integrons and phylogenetic groups of Escherichia coli isolates were determined by PCR/sequencing. Genomic relatedness was determined by multi-locus sequence typing (MLST) for selected isolates. In total, 57 ESBL-producer isolates were recovered (47 E. coli, eight Klebsiella pneumoniae, 1 of the Citrobacter freundii complex and 1 of the Enterobacter cloacae complex). The CTX-M-15 enzyme was the most frequently detected ESBL, followed by CTX-M-27, CTX-M-55 and SHV-12. One E. coli isolate harboured the mcr-1 gene. The following phylogroups/sequence types (STs) were identified among ESBL-producing E. coli isolates: B2/ST131 (subclade-C1), A/ST3221, A/ST8900, D/ST69, D/ST2142, D/ST38, B1/ST2460 and B1/ST6448. High numbers of isolates harboured the class 1 integrons with various gene cassette arrays as well as IncP-1 and IncFIB plasmids. Our findings confirm the importance of WWTPs as hotspot collectors of ESBL-producing Enterobacteriaceae with a high likelihood of spread to human and natural environments.


Assuntos
Proteínas de Escherichia coli , Purificação da Água , Antibacterianos/farmacologia , Colistina , Enterobacteriaceae/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Plasmídeos/genética , Tunísia , beta-Lactamases/genética
15.
Infect Genet Evol ; 81: 104263, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32105865

RESUMO

Colistin is a last-resort antibiotic for the treatment of infections caused by multidrug and carbapenem-resistant Gram-negative bacteria. Colistin resistance has been emerging and multiple outbreaks have been reported in Europe and elsewhere. It has been most frequently reported in carbapenem-resistant K. pneumoniae. In this study, 24 multidrug and colistin-resistant clinical isolates (14 K. pneumoniae, one E. aerogenes, one E. cloacae, and eight A. baumannii) were collected from four hospitals in Croatia from 2013 to 2018, in order to analyse the molecular epidemiology and mechanisms of antibiotic resistance. ß-lactamase and carbapenemase genes were detected by PCR. Genotyping was done on selected isolates by rep-PCR. Whole genome sequencing (WGS) was performed to discover possible molecular mechanisms for the observed colistin resistance. All isolates, except two K. pneumoniae isolates, were extensively drug resistant. Ten out of 16 (63%) K. pneumoniae isolates possessed blaOXA-48, which is the most common carbapenem resistance gene in Croatia and in other parts of Europe. All A. baumannii isolates possessed the OXA-23-like carbapenem hydrolysing oxacillinase and five turned out to be pandrug-resistant. Colistin resistance was most likely chromosomally mediated. After sequence analysis, none of the isolates were found to possess any of the mcr gene variants. Several previously reported mutations were found in PmrB, PhoP, PhoQ, and MgrB, which are associated with colistin resistance. In the global phylogenetic analysis, DNA mutations causing mutations in the MgrB protein were present mostly in lineages comprising colistin resistant isolates, and the second most prevalent mutation (K3X) was also encountered in our isolates. In addition, based on genotyping by rep-PCR, the spread of colistin resistance is most likely to be clonal. Most importantly, the presence of colistin resistance together with carbapenemase genes in extensively drug resistant isolates poses real threats in the use of carbapenems and colistin to fight infections.


Assuntos
Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/genética , Proteínas de Bactérias/genética , Colistina/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Enterobacteriaceae/genética , Enterobacteriaceae/genética , beta-Lactamases/genética , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/uso terapêutico , Proteínas de Bactérias/efeitos dos fármacos , Croácia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Filogenia , Sequenciamento Completo do Genoma/métodos , beta-Lactamases/efeitos dos fármacos
16.
Artigo em Inglês | MEDLINE | ID: mdl-32094137

RESUMO

Plazomicin was active against 97.0% of 8,783 Enterobacterales isolates collected in the United States (2016 and 2017), and only 6 isolates carried 16S rRNA methyltransferases conferring resistance to virtually all aminoglycosides. Plazomicin (89.2% to 95.9% susceptible) displayed greater activity than amikacin (72.5% to 78.6%), gentamicin (30.4% to 45.9%), and tobramycin (7.8% to 22.4%) against carbapenem-resistant and extensively drug-resistant isolates. The discrepancies among the susceptibility rates for these agents was greater when applying breakpoints generated using the same stringent contemporary methods applied to determine plazomicin breakpoints.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Sisomicina/análogos & derivados , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Hospitais , Humanos , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Sisomicina/farmacologia , Estados Unidos
17.
J Ethnopharmacol ; 247: 112299, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31606537

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hua-Feng-Dan (HFD) is a traditional Chinese medicine used for neurological disorders. HFD contains cinnabar (HgS) and realgar (As4S4). The ethnopharmacological basis of cinnabar and realgar in HFD is not known. AIM OF THE STUDY: To address the role of cinnabar and realgar in HFD-produced neuroprotection against neurodegenerative diseases and disturbance of gut microbiota. MATERIALS AND METHODS: Lipopolysaccharide (LPS) plus rotenone (ROT)-elicited rat dopaminergic (DA) neuronal damage loss was performed as a Parkinson's disease animal model. Rats were given a single injection of LPS. Four months later, rats were challenged with the threshold dose of ROT. The clinical dose of HFD was administered via feed, starting from ROT administration for 46 days. Behavioral dysfunction was detected by rotarod and Y-maze tests. DA neuron loss and microglial activation were assessed via immunohistochemical staining and western bolt analysis. The colon content was collected to extract bacterial DNA followed by real-time PCR analysis with 16S rRNA primers. RESULTS: LPS plus ROT induced neurotoxicity, as evidenced by DA neuron loss in substantia nigra, impaired behavioral functions and increased microglial activation. HFD-original (containing 10% cinnabar and 10% realgar) rescued loss of DA neurons, improved behavioral dysfunction and attenuated microglial activation. Compared with HFD-original, HFD-reduced (3% cinnabar and 3% realgar) was also effective, but to be a less extent, while HFD-removed (without cinnabar and realgar) was ineffective. In analysis of gut microbiome, the increased Verrucomicrobiaceae and Lactobacteriaceae, and the decreased Enterobacteeriaceae by LPS plus ROT were ameliorated by HFD-original, and to be the less extent by HFD-reduced. CONCLUSION: Cinnabar and realgar are active ingredients in HFD to exert beneficial effects in a neurodegenerative model and gut microbiota.


Assuntos
Arsenicais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Compostos de Mercúrio/farmacologia , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/tratamento farmacológico , Sulfetos/farmacologia , Animais , Arsenicais/química , Arsenicais/uso terapêutico , DNA Bacteriano/isolamento & purificação , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Etnofarmacologia , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/imunologia , Humanos , Mediadores da Inflamação/metabolismo , Lactobacillaceae/efeitos dos fármacos , Lactobacillaceae/genética , Lactobacillaceae/isolamento & purificação , Lipopolissacarídeos/toxicidade , Masculino , Compostos de Mercúrio/química , Compostos de Mercúrio/uso terapêutico , Microglia/efeitos dos fármacos , Microglia/imunologia , Microglia/patologia , Degeneração Neural , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/imunologia , Síndromes Neurotóxicas/patologia , RNA Ribossômico 16S/genética , Ratos , Rotenona/toxicidade , Sulfetos/química , Sulfetos/uso terapêutico , Verrucomicrobia/efeitos dos fármacos , Verrucomicrobia/genética , Verrucomicrobia/isolamento & purificação
18.
Plant Dis ; 103(11): 2893-2902, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31436473

RESUMO

Uniqprimer, a software pipeline developed in Python, was deployed as a user-friendly internet tool in Rice Galaxy for comparative genome analyses to design primer sets for PCRassays capable of detecting target bacterial taxa. The pipeline was trialed with Dickeya dianthicola, a destructive broad-host-range bacterial pathogen found in most potato-growing regions. Dickeya is a highly variable genus, and some primers available to detect this genus and species exhibit common diagnostic failures. Upon uploading a selection of target and nontarget genomes, six primer sets were rapidly identified with Uniqprimer, of which two were specific and sensitive when tested with D. dianthicola. The remaining four amplified a minority of the nontarget strains tested. The two promising candidate primer sets were trialed with DNA isolated from 116 field samples from across the United States that were previously submitted for testing. D. dianthicola was detected in 41 samples, demonstrating the applicability of our detection primers and suggesting widespread occurrence of D. dianthicola in North America.


Assuntos
Agricultura , Técnicas Bacteriológicas , Primers do DNA , Enterobacteriaceae , Solanum tuberosum , Agricultura/métodos , Técnicas Bacteriológicas/métodos , Primers do DNA/genética , Enterobacteriaceae/genética , América do Norte , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia
19.
J Clin Microbiol ; 57(9)2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31243084

RESUMO

Given increasing antimicrobial resistance, we aimed to determine antibiotic susceptibility and presence of resistance genes in uropathogens in primary care, factors associated with resistance to commonly prescribed antibiotics, and effect of treatment on early symptom resolution. We conducted a prospective study of primary care patients with urinary tract infection (UTI) symptoms and culture-confirmed UTI in Singapore from 2015 to 2016. Cohort characteristics and antimicrobial susceptibility of cultured isolates were analyzed. Among Enterobacteriaceae isolates, early symptom resolution (within 3 days) according to antibiotic prescribed and isolate susceptibility and factors associated with antibiotic resistance were evaluated. Of 695 symptomatic patients, 299 were urine culture positive; of these 299 patients, 259 (87%) were female. Escherichia coli was the most common uropathogen (76%). Enterobacteriaceae isolates (n = 283) were highly susceptible to amoxicillin-clavulanate (86%), nitrofurantoin (87%), and fosfomycin (98%), but >20% were resistant to ciprofloxacin and co-trimoxazole. Isolates resistant to appropriate indicator antibiotics were further tested to determine proportions positive for blaCTX-M (14/26, 54%), plasmid-mediated ampC (12/24, 50%), qnr (7/69, 10%), and fos (1/6, 17%) resistance genes. A total of 67% of patients given antibiotics with susceptible isolates reported early resolution versus 45% given antibiotics with nonsusceptible isolates (P = 0.001) and 27% not treated (P = 0.018). On multivariable analysis, Indian ethnicity and diabetes mellitus were associated with amoxicillin-clavulanate resistance. Genitourinary abnormalities, UTI in the past 12 months, and hospitalization in the past 6 months were associated with ciprofloxacin and co-trimoxazole resistance. Patients given active empirical antibiotics were most likely to report early symptom resolution, but correlation with in vitro susceptibility was imperfect. Factors associated with resistance may guide the decision to obtain initial urine culture.


Assuntos
Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Genes Bacterianos , Infecções Urinárias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Atenção Primária à Saúde , Estudos Prospectivos , Singapura , Resultado do Tratamento , Infecções Urinárias/microbiologia , Adulto Jovem
20.
Eur J Clin Microbiol Infect Dis ; 38(4): 755-765, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30680569

RESUMO

Kidney transplant recipients are at risk for infections due to carbapenem-resistant Enterobacteriaceae (CRE). Polymyxin-resistant CRE (PR-CRE) infections are especially difficult to treat. The aim of this study was to characterize PR-CRE infections among kidney transplant recipients and identify risk factors for treatment failure. This retrospective cohort study involved all kidney transplant recipients with PR-CRE infection between 2013 and 2017 at our center. Minimal inhibitory concentrations for polymyxin B were determined by broth microdilution. Carbapenem-resistant genes (blaKPC, blaNDM, and blaOXA-48), aminoglycoside-resistance genes, and polymyxin-resistant gene mcr-1 were identified by polymerase chain reaction. All but one of the 47PR-CRE infections identified were due to Klebsiella pneumoniae. The most common type of infection (in 54.3%) was urinary tract infection (UTI). Monotherapy was used in 10 cases. Combined treatment regimens included double-carbapenem therapy in 19 cases, oral fosfomycin in 19, and amikacin in 13. Treatment failure occurred in 21 cases (45.7%). Clinical success was achieved 78.9% of patients who used aminoglycosides versus 37.0% of those who not used this drug (p = 0.007). Multivariate analysis showed diabetes mellitus to be a risk factor for treatment failure; amikacin use and UTI were found to be protective. Nine strains were RmtB producers. Although aminoglycosides constitute an important therapeutic option for PR-CRE infection, the emergence of aminoglycoside resistance could have a major impact on the management of CRE infection.


Assuntos
Aminoglicosídeos/uso terapêutico , Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Polimixinas/farmacologia , Adulto , Idoso , Amicacina/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Quimioterapia Combinada , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/mortalidade , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Feminino , Fosfomicina/uso terapêutico , Humanos , Transplante de Rim , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Transplantados , Falha de Tratamento , Resultado do Tratamento
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