Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
1.
Infect Genet Evol ; 121: 105598, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38653335

RESUMO

Klebsiella pneumoniae is an opportunistic pathogen that can colonize the gastrointestinal tract (GIT) of humans. The mechanisms underlying the successful translocation of this pathogen to cause extra-intestinal infections remain unknown, although virulence and antimicrobial resistance traits likely play significant roles in the establishment of infections. We investigated K. pneumoniae strains isolated from GIT colonization (strains Kp_FZcol-1, Kp_FZcol-2 and Kp_FZcro-1) and from a fatal bloodstream infection (strain Kp_HM-1) in a leukemia patient. All strains belonged to ST307, carried a transferable IncF plasmid containing the blaCTX-M-15 gene (pKPN3-307 TypeA-like plasmid) and showed a multidrug-resistance phenotype. Phylogenetic analysis demonstrated that Kp_HM-1 was more closely related to Kp_FZcro-1 than to the other colonizing strains. The Kp_FZcol-2 genome showed 81 % coverage with the Kp_HM-1 246,730 bp plasmid (pKp_HM-1), lacking most of its putative virulence genes. Searching public genomes with similar coverage, we observed the occurrence of this deletion in K. pneumoniae ST307 strains recovered from human colonization and infection in different countries. Our findings suggest that strains lacking the putative virulence genes found in the pKPN3-307 TypeA plasmid are still able to colonize and infect humans, highlighting the need to further investigate the role of these genes for the adaptation of K. pneumoniae ST307 in distinct human body sites.


Assuntos
Trato Gastrointestinal , Infecções por Klebsiella , Klebsiella pneumoniae , Leucemia , Filogenia , beta-Lactamases , Humanos , Masculino , Antibacterianos/farmacologia , Bacteriemia/microbiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Trato Gastrointestinal/microbiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidade , Klebsiella pneumoniae/efeitos dos fármacos , Leucemia/microbiologia , Leucemia/complicações , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Virulência/genética , Fatores de Virulência/genética , Pessoa de Meia-Idade
2.
Clin Infect Dis ; 77(Suppl 1): S29-S37, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37406041

RESUMO

BACKGROUND: Carbapenemase production is a global public health threat. Antimicrobial resistance (AMR) data analysis is critical to public health policy. Here we analyzed carbapenemase detection trends using the AMR Brazilian Surveillance Network. METHODS: Carbapenemase detection data from Brazilian hospitals included in the public laboratory information system dataset were evaluated. The detection rate (DR) was defined as carbapenemase detected by gene tested per isolate per year. The temporal trends were estimated using the Prais-Winsten regression model. The impact of COVID-19 on carbapenemase genes in Brazil was determined for the period 2015-2022. Detection pre- (October 2017 to March 2020) and post-pandemic onset (April 2020 to September 2022) was compared using the χ2 test. Analyses were performed with Stata 17.0 (StataCorp, College Station, TX). RESULTS: 83 282 blaKPC and 86 038 blaNDM were tested for all microorganisms. Enterobacterales DR for blaKPC and blaNDM was 68.6% (41 301/60 205) and 14.4% (8377/58 172), respectively. P. aeruginosa DR for blaNDM was 2.5% (313/12 528). An annual percent increase for blaNDM of 41.1% was observed, and a decrease for blaKPC of -4.0% in Enterobacterales, and an annual increase for blaNDM of 71.6% and for blaKPC of 22.2% in P. aeruginosa. From 2020 to 2022, overall increases of 65.2% for Enterobacterales, 77.7% for ABC, and 61.3% for P. aeruginosa were observed in the total isolates. CONCLUSIONS: This study shows the strengths of the AMR Brazilian Surveillance Network with robust data related to carbapenemases in Brazil and the impact of COVID-19 with a change in carbapenemase profiles with blaNDM rising over the years.


Assuntos
Acinetobacter baumannii , COVID-19 , Humanos , Pseudomonas aeruginosa/genética , Carbapenêmicos/farmacologia , Acinetobacter baumannii/genética , Brasil/epidemiologia , Pandemias , COVID-19/epidemiologia , Proteínas de Bactérias/genética , beta-Lactamases/genética , Plasmídeos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
3.
Braz J Microbiol ; 54(1): 135-141, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36327041

RESUMO

Carbapenems are considered last-resort antibiotics for the treatment of infections caused by multidrug-resistant Gram-negative bacteria. Although the main mechanism of carbapenem-resistance in Pseudomonas aeruginosa is the loss of OprD porin, carbapenemases continue to be a problem worldwide. The aim of this study was to evaluate the performance of phenotypic tests (Carba NP, Blue Carba, and mCIM/eCIM) for detection of carbapenemase-producing Pseudomonas spp. in Brazil. One hundred twenty-seven Pseudomonas spp. clinical isolates from different Brazilian states were submitted to phenotypic and molecular carbapenemase detection. A total of 90 carbapenemase-producing P. aeruginosa and 5 Pseudomonas putida (35, blaVIM-2; 17, blaSPM-1; 2, blaIMP-10; 1, blaVIM-24; 1, blaNDM-1; 39, blaKPC-2). The phenotypic Carba NP, Blue Carba, and mCIM/eCIM showed sensitivity of 94.7%, 93.6%, and 93.6%, and specificity of 90.6%, 100%, and 96.8%, respectively. However, only the Carba NP presented the highest sensitivity and showed the ability in differentiating the carbapenemases between class A and class B using EDTA. Blue Carba failed to detect most of the class B carbapenemases, having the worst performance using EDTA. Our results show changes in the epidemiology of the spread of carbapenemases and the importance of their detection by phenotypic and genotypic tests. Such, it is essential to use analytical tools that faithfully detect bacterial resistance in vitro in a simple, sensitive, rapid, and cost-effective way. Much effort must be done to improve the current tests and for the development of new ones.


Assuntos
Pseudomonas , beta-Lactamases , Ácido Edético/farmacologia , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/farmacologia , Antibacterianos/farmacologia , Sensibilidade e Especificidade
4.
Front Pharmacol ; 13: 948339, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204235

RESUMO

Antibacterial drugs are a widely used drug class due to the frequency of infectious diseases globally. Risks knowledge should ground these medicines' selection. Data mining in large databases is essential to identify early safety signals and to support pharmacovigilance systems. We conducted a cross-sectional study to assess adverse drug events related to antibiotics reporting between December 2018 and December 2021 in the Brazilian database (Vigimed/VigiFlow). We used the Reporting Odds Ratio (ROR) disproportionality analysis method to identify disproportionate reporting signals (SDR), referring to statistical combinations between drugs and adverse events. Vancomycin was the most reported antibiotic (n = 1,733), followed by ceftriaxone (n = 1,277) and piperacillin and tazobactam (n = 1,024). We detected 294 safety signals related to antibacterials. We identified azithromycin leading in the number of safety signals (n = 49), followed by polymyxin B (n = 25). Of these, 95 were not provided for in the drug label and had little or no reports in the medical literature. Three serious events are associated with ceftazidime and avibactam, a new drug in the Brazilian market. We also found suicide attempts as a sign associated with amoxicillin/clavulanate. Gait disturbance, a worrying event, especially in the elderly, was associated with azithromycin. Our findings may help guide further pharmacoepidemiologic studies and monitoring safety signals in pharmacovigilance.

5.
Mem Inst Oswaldo Cruz ; 117: e220111, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36259790

RESUMO

BACKGROUND: Healthcare-associated infections due to multidrug-resistant (MDR) bacteria such as Pseudomonas aeruginosa are significant public health issues worldwide. A system biology approach can help understand bacterial behaviour and provide novel ways to identify potential therapeutic targets and develop new drugs. Gene regulatory networks (GRN) are examples of in silico representation of interaction between regulatory genes and their targets. OBJECTIVES: In this work, we update the MDR P. aeruginosa CCBH4851 GRN reconstruction and analyse and discuss its structural properties. METHODS: We based this study on the gene orthology inference methodology using the reciprocal best hit method. The P. aeruginosa CCBH4851 genome and GRN, published in 2019, and the P. aeruginosa PAO1 GRN, published in 2020, were used for this update reconstruction process. FINDINGS: Our result is a GRN with a greater number of regulatory genes, target genes, and interactions compared to the previous networks, and its structural properties are consistent with the complexity of biological networks and the biological features of P. aeruginosa. MAIN CONCLUSIONS: Here, we present the largest and most complete version of P. aeruginosa GRN published to this date, to the best of our knowledge.


Assuntos
Infecção Hospitalar , Infecções por Pseudomonas , Humanos , Pseudomonas aeruginosa/genética , Redes Reguladoras de Genes/genética , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Pseudomonas/genética , Antibacterianos
6.
J Glob Antimicrob Resist ; 31: 38-44, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35948241

RESUMO

OBJECTIVES: In contrast to other qnr families, qnrVC has been reported mainly in Vibrio spp. and inserted in class 1 integrons. This study aimed to identify the variants of qnrVC genes detected in Klebsiella pneumoniae carbapenemase-2-producing Enterobacter and Klebsiella strains isolated from Brazilian coastal waters and the genetic contexts associated with their occurrence. METHODS: qnrVC variants were identified by Sanger sequencing. Stains were typified by pulsed-field gel electrophoresis. Antimicrobial susceptibility testing, conjugation assays, and whole genome sequencing (WGS) were applied to identify the strains' antimicrobial resistance profile, qnrVC and blaKPC-2 co-transference, and qnrVC genetic context. RESULTS: qnrVC1 was identified in 15 Enterobacter and 3 Klebsiella, and qnrVC4 in 2 Enterobacter strains. Pulsed-field gel electrophoresis revealed 12 clonal profiles of Enterobacter and one of Klebsiella. Strains were resistant to aminoglycosides, beta-lactams, fosfomycin, quinolones, and sulfamethoxazole-trimethoprim. Co-transference of qnrVC and blaKPC-2 were obtained from five representative Enterobacter strains, which showed resistance to ampicillin and amoxicillin-clavulanate, and reduced susceptibility to extended-spectrum cephalosporins, meropenem, and ciprofloxacin. WGS analysis from representative strains revealed one K. quasipneumoniae subsp. similipneumoniae, one E. soli, four E. kobei, and seven isolates belonging to Enterobacter Taxon 3. Long-read WGS showed qnrVC and blaKPC-2 were carried by the same replicon on Klebsiella and Enterobacter strains, and the qnrVC association with not previously described genetic environments composed of insertion sequences and truncated genes. These contexts occurred in small- and high-molecular-weight plasmids belonging to IncFII, IncP6, pKPC-CAV1321, and IncU groups. CONCLUSION: Our results suggest that the dissemination of qnrVC among Enterobacterales in Brazilian coastal waters is associated with several genetic recombination events.


Assuntos
Enterobacter , Klebsiella , Antibacterianos/farmacologia , Enterobacter/genética , Klebsiella/genética , Klebsiella pneumoniae/genética
7.
Front Microbiol ; 13: 893474, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711759

RESUMO

Due to recent developments in NGS technologies, genome sequencing is generating large volumes of new data containing a wealth of biological information. Understanding sequenced genomes in a biologically meaningful way and delineating their functional and metabolic landscapes is a first-level challenge. Considering the global antimicrobial resistance (AMR) problem, investments to expand surveillance and improve existing genome analysis technologies are pressing. In addition, the speed at which new genomic data is generated surpasses our capacity to analyze it with available bioinformatics methods, thus creating a need to develop new, user-friendly and comprehensive analytical tools. To this end, we propose a new web application, CABGen, developed with open-source software. CABGen allows storing, organizing, analyzing, and interpreting bioinformatics data in a friendly, scalable, easy-to-use environment and can process data from bacterial isolates of different species and origins. CABGen has three modules: Upload Sequences, Analyze Sequences, and Verify Results. Functionalities include coverage estimation, species identification, de novo genome assembly, and assembly quality, genome annotation, MLST mapping, searches for genes related to AMR, virulence, and plasmids, and detection of point mutations in specific AMR genes. Visualization tools are also available, greatly facilitating the handling of biological data. The reports include those results that are clinically relevant. To illustrate the use of CABGen, whole-genome shotgun data from 181 bacterial isolates of different species collected in 5 Brazilian regions between 2018 and 2020 were uploaded and submitted to the platform's modules.

8.
Infect Genet Evol ; 102: 105302, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35568335

RESUMO

The high rates of carbapenem resistance among Brazilian Pseudomonas aeruginosa isolates are mainly associated with the clone ST277 producing the carbapenemase SPM-1. Here, the complete genetic composition of a IncP plasmid harboring blaKPC-2 in isolates of this endemic clone carrying chromosomal blaSPM-1 was described using whole genome sequencing. These results confirm the association of these two carbapenemases in ST277 and also describe the genetic composition of a novel blaKPC-2-plasmid. Considering the fact that this association occurs in a high-risk clone, monitoring the dissemination of this plasmid should be a public health concern.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Brasil/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/genética , beta-Lactamases/genética
9.
Microb Drug Resist ; 28(1): 1-6, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34264760

RESUMO

This study was conducted to determine the molecular epidemiology of blaKPC-encoding Klebsiella pneumoniae recovered from three public hospitals in Brazil. Molecular investigation of blaOXA-48, blaKPC, blaNDM, blaCTX-M, blaSHV, blaTEM, blaIMP, and blaVIM resistance genes was performed in 99 K. pneumoniae isolates from inpatients of intensive care units. Antimicrobial susceptibility was determined with a Vitek-2 System, except for polymyxin B, which was evaluated by the microbroth dilution test. Clonal relatedness was established by pulsed-field gel electrophoresis and multilocus sequence typing. Screening resistance genes showed that K. pneumoniae isolates carried the blaKPC (88.9%), blaSHV (73.5%), blaTEM (72.2%), and blaCTX-M (43.9%) genes. The most frequent sequence types (STs) were ST273, ST11, ST 1298, ST13, ST2687, and ST37. We report new STs in K. pneumoniae that have not been detected previously in Brazil. K. pneumoniae belonging to the same clone is present in different hospitals in the same region, showing the spread of multidrug-resistant K. pneumoniae.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Brasil , Genes Bacterianos , Hospitais Públicos , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , beta-Lactamases/genética
10.
Mem. Inst. Oswaldo Cruz ; 117: e220111, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1405995

RESUMO

BACKGROUND Healthcare-associated infections due to multidrug-resistant (MDR) bacteria such as Pseudomonas aeruginosa are significant public health issues worldwide. A system biology approach can help understand bacterial behaviour and provide novel ways to identify potential therapeutic targets and develop new drugs. Gene regulatory networks (GRN) are examples of in silico representation of interaction between regulatory genes and their targets. OBJECTIVES In this work, we update the MDR P. aeruginosa CCBH4851 GRN reconstruction and analyse and discuss its structural properties. METHODS We based this study on the gene orthology inference methodology using the reciprocal best hit method. The P. aeruginosa CCBH4851 genome and GRN, published in 2019, and the P. aeruginosa PAO1 GRN, published in 2020, were used for this update reconstruction process. FINDINGS Our result is a GRN with a greater number of regulatory genes, target genes, and interactions compared to the previous networks, and its structural properties are consistent with the complexity of biological networks and the biological features of P. aeruginosa. MAIN CONCLUSIONS Here, we present the largest and most complete version of P. aeruginosa GRN published to this date, to the best of our knowledge.

11.
Front Mol Biosci ; 8: 728129, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616771

RESUMO

Pseudomonas aeruginosa is an opportunistic human pathogen that has been a constant global health problem due to its ability to cause infection at different body sites and its resistance to a broad spectrum of clinically available antibiotics. The World Health Organization classified multidrug-resistant Pseudomonas aeruginosa among the top-ranked organisms that require urgent research and development of effective therapeutic options. Several approaches have been taken to achieve these goals, but they all depend on discovering potential drug targets. The large amount of data obtained from sequencing technologies has been used to create computational models of organisms, which provide a powerful tool for better understanding their biological behavior. In the present work, we applied a method to integrate transcriptome data with genome-scale metabolic networks of Pseudomonas aeruginosa. We submitted both metabolic and integrated models to dynamic simulations and compared their performance with published in vitro growth curves. In addition, we used these models to identify potential therapeutic targets and compared the results to analyze the assumption that computational models enriched with biological measurements can provide more selective and (or) specific predictions. Our results demonstrate that dynamic simulations from integrated models result in more accurate growth curves and flux distribution more coherent with biological observations. Moreover, identifying drug targets from integrated models is more selective as the predicted genes were a subset of those found in the metabolic models. Our analysis resulted in the identification of 26 non-host homologous targets. Among them, we highlighted five top-ranked genes based on lesser conservation with the human microbiome. Overall, some of the genes identified in this work have already been proposed by different approaches and (or) are already investigated as targets to antimicrobial compounds, reinforcing the benefit of using integrated models as a starting point to selecting biologically relevant therapeutic targets.

12.
Front Med (Lausanne) ; 8: 635206, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791325

RESUMO

Multidrug-resistant microorganisms are a well-known global problem, and gram-negative bacilli are top-ranking. When these pathogens are associated with bloodstream infections (BSI), outcomes become even worse. Here we applied whole-genome sequencing to access information about clonal distribution, resistance mechanism diversity and other molecular aspects of gram-negative bacilli (GNB) isolated from bloodstream infections in Brazil. It was possible to highlight international high-risk clones circulating in the Brazilian territory, such as CC258 for Klebsiella pneumoniae, ST79 for Acinetobacter baumannii and ST233 for Pseudomonas aeruginosa. Important associations can be made such as a negative correlation between CRISPR-Cas and K. pneumoniae CC258, while the genes bla TEM, bla KPC and bla CTX-M are highly associated with this clone. Specific relationships between A. baumannii clones and bla OXA-51 variants were also observed. All P. aeruginosa ST233 isolates showed the genes bla VIM and bla OXA486. In addition, some trends could be identified, where a new P. aeruginosa MDR clone (ST3079), a novel A. baumannii clonal profile circulating in Brazil (ST848), and important resistance associations in the form of bla VIM-2 and bla IMP-56 being found together in one ST233 strain, stand out. Such findings may help to develop approaches to deal with BSI and even other nosocomial infections caused by these important GNB.

13.
Microbes Infect ; 23(4-5): 104801, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33582283

RESUMO

Acinetobacter baumannii is an important nosocomial pathogen. BamA is a protein that belongs to a complex responsible for organizing the proteins on the bacterial outer membrane. In this work, we aimed to evaluate murine immune responses to BamA recombinant protein (rAbBamA) from A. baumannii in an animal model of infection, and to assess cross-reactivity of this target for the development of anti-A. baumannii vaccines or diagnostics. Immunization of mice with rAbBamA elicited high antibody titers and antibody recognition of native A. baumannii BamA. Immunofluorescence also detected binding to the bacterial surface. After challenge, immunized mice demonstrated a 40% survival increase and better bacterial clearance in kidneys. Immunoblot of anti-rAbBamA against other medically relevant bacteria showed binding to proteins of approximately 35 kDa in Klebsiella pneumoniae and Escherichia coli lysates, primarily identified as OmpA and OmpC, respectively. Altogether, our data show that anti-rAbBamA antibodies provide a protective response against A. baumannii infection in mice. However, the response elicited by immunization with rAbBamA is not completely specific to A. baumannii. Although a broad-spectrum vaccine that protects against various pathogens is an appealing strategy, antibody reactivity against the human microbiota is undesired. In fact, immunization with rAbBamA produced noticeable effects on the gut microbiota. However, the changes elicited were small and non-specific, given that no significant changes in the abundance of Proteobacteria were observed. Overall, rAbBamA is a promising target, but specificity must be considered in the development of immunological tools against A. baumannii.


Assuntos
Infecções por Acinetobacter/prevenção & controle , Acinetobacter baumannii/metabolismo , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/imunologia , Acinetobacter baumannii/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Proteínas da Membrana Bacteriana Externa/química , Clonagem Molecular , DNA Bacteriano/química , Fezes/química , Feminino , Microbioma Gastrointestinal , Regulação Bacteriana da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Ribossômico 16S/química , Proteínas Recombinantes/imunologia
14.
Curr Microbiol ; 78(2): 696-704, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33404752

RESUMO

Pseudomonas aeruginosa is associated with chronic and progressive lung disease and is closely related to increased morbidity and mortality in cystic fibrosis (CF) patients. Hypermutable (HPM) P. aeruginosa isolates have been described in these patients and are usually associated with antibiotic resistance. This study aimed to investigate the occurrence of carbapenem resistance and hypermutable phenotype in 179 P. aeruginosa isolates from 8 chronically CF patients assisted at two reference centers in Rio de Janeiro, Brazil. Using disk diffusion test, non-susceptible (NS) rates higher than 40% were observed for imipenem, amikacin, and gentamicin. A total of 79 isolates (44.1%), 71 (39.6%), and 8 (4.4%) were classified as carbapenem-resistant (CR resistance to at least one carbapenem), multidrug-resistant (MDR), and extensively drug-resistant (XDR), respectively. Minimal inhibitory concentration was determined for 79 CR P. aeruginosa and showed the following variations: 4 and 128 µg/mL to imipenem, 4 and 64 µg/mL to meropenem, and 4 and ≥ 32 µg/mL to doripenem. We have found only four (2.23%) HPM isolates from 4 patients. Analyzing the genetic relationship among the HPM isolates, 3 pulsed-field gel electrophoresis/pulsotypes (D, M, and J) were observed. Only M pulsotype was recovered from two patients in different years. Polymerase chain reaction screening for blaGES, blaIMP, blaKPC, blaNDM, blaOXA-48, blaSPM, and blaVIM genes was performed for all CR isolates and none of them were positive. Our results demonstrate a high occurrence of CR and MDR P. aeruginosa of CF patients follow-up in both centers studied, while the presence of HPM is still unusual.


Assuntos
Fibrose Cística , Infecções por Pseudomonas , Antibacterianos/farmacologia , Brasil , Carbapenêmicos/farmacologia , Fibrose Cística/complicações , Humanos , Pulmão , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/genética , beta-Lactamases
15.
Microb Drug Resist ; 27(5): 721-725, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33001761

RESUMO

Emergence of colistin-resistant bacteria harboring mobile colistin resistance genes (mcr genes) pose a threat for food-producing animals and humans. In this article, we aim to highlight the emergence of Escherichia fergusonii as an important new reservoir to mcr-1-harboring plasmid in poultry production. Three strains closely related were isolated from cloacal swabs. Their genome contains four plasmids, including a 182,869 bp IncHI2 plasmid harboring the colistin resistance gene mcr-1. These results will contribute to our understanding of plasmid-mediated mcr-1 gene presence and transmission in E. fergusonii.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia/efeitos dos fármacos , Escherichia/genética , Genes Bacterianos/genética , Proteínas de Bactérias , Brasil , Plasmídeos
17.
Sci Rep ; 10(1): 13192, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32764694

RESUMO

Pseudomonas aeruginosa is one of the most common pathogens related to healthcare-associated infections. The Brazilian isolate, named CCBH4851, is a multidrug-resistant clone belonging to the sequence type 277. The antimicrobial resistance mechanisms of the CCBH4851 strain are associated with the presence of the bla[Formula: see text] gene, encoding a metallo-beta-lactamase, in combination with other exogenously acquired genes. Whole-genome sequencing studies focusing on emerging pathogens are essential to identify key features of their physiology that may lead to the identification of new targets for therapy. Using both Illumina and PacBio sequencing data, we obtained a single contig representing the CCBH4851 genome with annotated features that were consistent with data reported for the species. However, comparative analysis with other Pseudomonas aeruginosa strains revealed genomic differences regarding virulence factors and regulatory proteins. In addition, we performed phenotypic assays that revealed CCBH4851 is impaired in bacterial motilities and biofilm formation. On the other hand, CCBH4851 genome contained acquired genomic islands that carry transcriptional factors, virulence and antimicrobial resistance-related genes. Presence of single nucleotide polymorphisms in the core genome, mainly those located in resistance-associated genes, suggests that these mutations may also influence the multidrug-resistant behavior of CCBH4851. Overall, characterization of Pseudomonas aeruginosa CCBH4851 complete genome revealed the presence of features that strongly relates to the virulence and antibiotic resistance profile of this important infectious agent.


Assuntos
Genômica , Fenótipo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , beta-Lactamases/biossíntese , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Genoma Bacteriano/genética , Ilhas Genômicas/genética , Polimorfismo de Nucleotídeo Único , Pseudomonas aeruginosa/efeitos dos fármacos
18.
BMC Genomics ; 21(1): 255, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32293244

RESUMO

BACKGROUND: The Brazilian endemic clone Pseudomonas aeruginosa ST277 carries important antibiotic resistance determinants, highlighting the gene coding for SPM-1 carbapenemase. However, the resistance and persistence of this clone is apparently restricted to the Brazilian territory. To understand the differences between Brazilian strains from those isolated in other countries, we performed a phylogenetic analysis of 47 P. aeruginosa ST277 genomes as well as analyzed the virulence and resistance gene profiles. Furthermore, we evaluated the distribution of genomic islands and assessed in detail the characteristics of the CRISPR-Cas immunity system in these isolates. RESULTS: The Brazilian genomes presented a typical set of resistance and virulence determinants, genomic islands and a high frequency of the CRISPR-Cas system type I-C. Even though the ST277 genomes are closely related, the phylogenetic analysis showed that the Brazilian strains share a great number of exclusively SNPs when compared to other ST277 genomes. We also observed a standard CRISPR spacers content for P. aeruginosa ST277, confirming a strong link between sequence type and spacer acquisition. Most CRISPR spacer targets were phage sequences. CONCLUSIONS: Based on our findings, P. aeruginosa ST277 strains circulating in Brazil characteristically acquired In163 and PAGI-25, which can distinguish them from strains that do not accumulate resistance mechanisms and can be found on the Asian, European and North American continents. The distinctive genetic elements accumulated in Brazilian samples can contribute to the resistance, pathogenicity and transmission success that characterize the ST277 in this country.


Assuntos
Proteínas de Bactérias/genética , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Brasil/epidemiologia , Sistemas CRISPR-Cas , Células Clonais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Resistência Microbiana a Medicamentos/genética , Genoma Bacteriano , Ilhas Genômicas , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único , Pseudomonas aeruginosa/patogenicidade
19.
Microb Drug Resist ; 26(6): 652-660, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31851584

RESUMO

KPC-producing Klebsiella pneumoniae (KPC-Kp) has become an important public health issue. The previous intestinal colonization by KPC-Kp has been an important risk factor associated with the progression to infections. The objective of this study was to assess the genetic characterization of KPC-Kp isolates recovered from human rectal swabs in Brazil. We selected 102 KPC-Kp isolates collected during 2009-2013 in 11 states. Antimicrobial susceptibility was determined by disk diffusion, E-test, and broth microdilution. The resistance and virulence genes were investigated by PCR. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The isolates were mostly resistant to ß-lactams, sulfonamides, chloramphenicol, quinolones, and aminoglycosides but susceptible to fosfomycin/trometamol, polymyxin B, and tigecycline. The blaKPC-2 was mostly associated with Tn4401b. Besides that, the isolates carried blaCTX-M, blaSHV, blaTEM, and aac(6')-Ib in high frequency and aac(3')IIa and qnr genes in moderate frequency. The PFGE revealed 26 pulsotypes and MLST performed in representative strains revealed 23 sequence types, 45% belonging to clonal complex 258 (CC258). Isolates of CC258 were found in all states. Seventy percent of the 102 KPC-Kp isolates belonged to CC258-associated pulsotypes. We describe the dissemination of KPC-2-Kp associated with Tn4401b belonging to CC258 colonizing patients in Brazil, which is also prevalent in infected patients, suggesting a clear colonization-infection correlation.


Assuntos
Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Farmacorresistência Bacteriana Múltipla/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Brasil/epidemiologia , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Genes Bacterianos , Humanos , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem Molecular , Tipagem de Sequências Multilocus
20.
Braz J Microbiol ; 51(3): 1125-1127, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31858443

RESUMO

Stenotrophomonas maltophilia is one of the Gram-negative bacilli most frequently found in the airways of cystic fibrosis patients. This opportunistic pathogen is intrinsically multidrug-resistant, and therefore, its treatment presents a challenge. The genetic characterization of S. maltophilia is largely unknown, especially from those strains that colonize/infect the airways of cystic fibrosis patients. This work reports the draft genome sequences of three S. maltophilia isolates recovered from the sputum of a cystic fibrosis pediatric patient in Southeast Brazil. Several resistance- and virulence-related genes were detected. Furthermore, one intact phage and one incomplete prophage region were also identified in all strains. Multilocus sequence typing showed that all strains belonged to a new sequence type (ST264). Interestingly, all S. maltophilia strains were genetically identical, showing persistence for at least 16 months. To our knowledge, this is the first report of S. maltophilia draft genome sequences obtained from a cystic fibrosis pediatric patient in Brazil.


Assuntos
Fibrose Cística/microbiologia , Genoma Bacteriano , Infecções por Bactérias Gram-Negativas/microbiologia , Stenotrophomonas maltophilia/genética , Antibacterianos/farmacologia , Sequência de Bases , Brasil , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Stenotrophomonas maltophilia/efeitos dos fármacos , Stenotrophomonas maltophilia/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...