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1.
J Clin Microbiol ; 62(2): e0121123, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38284762

RESUMO

The reliability of Fourier-transform infrared (FT-IR) spectroscopy for Klebsiella pneumoniae typing and outbreak control has been previously assessed, but issues remain in standardization and reproducibility. We developed and validated a reproducible FT-IR with attenuated total reflectance (ATR) workflow for the identification of K. pneumoniae lineages. We used 293 isolates representing multidrug-resistant K. pneumoniae lineages causing outbreaks worldwide (2002-2021) to train a random forest classification (RF) model based on capsular (KL)-type discrimination. This model was validated with 280 contemporaneous isolates (2021-2022), using wzi sequencing and whole-genome sequencing as references. Repeatability and reproducibility were tested in different culture media and instruments throughout time. Our RF model allowed the classification of 33 capsular (KL)-types and up to 36 clinically relevant K. pneumoniae lineages based on the discrimination of specific KL- and O-type combinations. We obtained high rates of accuracy (89%), sensitivity (88%), and specificity (92%), including from cultures obtained directly from the clinical sample, allowing to obtain typing information the same day bacteria are identified. The workflow was reproducible in different instruments throughout time (>98% correct predictions). Direct colony application, spectral acquisition, and automated KL prediction through Clover MS Data analysis software allow a short time-to-result (5 min/isolate). We demonstrated that FT-IR ATR spectroscopy provides meaningful, reproducible, and accurate information at a very early stage (as soon as bacterial identification) to support infection control and public health surveillance. The high robustness together with automated and flexible workflows for data analysis provide opportunities to consolidate real-time applications at a global level. IMPORTANCE We created and validated an automated and simple workflow for the identification of clinically relevant Klebsiella pneumoniae lineages by FT-IR spectroscopy and machine-learning, a method that can be extremely useful to provide quick and reliable typing information to support real-time decisions of outbreak management and infection control. This method and workflow is of interest to support clinical microbiology diagnostics and to aid public health surveillance.


Assuntos
Bactérias , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Sequenciamento Completo do Genoma , Proteínas Mutadas de Ataxia Telangiectasia
2.
Int J Mol Sci ; 25(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39063130

RESUMO

Carbapenemase-producing Enterobacterales are increasingly being recognized in nosocomial infections. The performance of a flow cytometry-based rapid assay for their detection and differentiation was evaluated. This is a disruptive phenotypic technology, phenotypic and growth-independent, that searches for the lesions produced by drugs acting on cells after a short incubation time. Overall, 180 Gram-negative bacteria were studied, and results were compared with those obtained molecularly by PCR and phenotypically by 'KPC, MBL and OXA-48 Confirm Kit'. This phenotypic method was used as reference for comparison purposes. Susceptibility to carbapenems (imipenem, meropenem, and ertapenem) was determined by standard broth microdilution. Overall, 112 isolates (62.2%) were carbapenemase producers, 41 KPCs, 36 MßLs, and 31 OXA-48, and 4 strains were KPC + MßL co-producers. Sixty-eight isolates were carbapenemase-negative. The percentage of agreement, sensitivity, and specificity were calculated according to ISO 20776-2:2021. The FASTinov assay showed 97.7% agreement with the reference method for carbapenemase detection. Discrepant flow cytometry results were obtained in four isolates compared with both reference and PCR results. The sensitivity and specificity of this new technology were 95.3% and 98.5%, respectively, for KPCs, 97.6% and 99.3% for MßLs, and 96.9% and 98% for OXA-48 detection. In conclusion, we describe a rapid flow cytometry assay with high accuracy for carbapenemase detection and the differentiation of various carbapenemases, which should impact clinical microbiology laboratories and patient management.


Assuntos
Proteínas de Bactérias , Citometria de Fluxo , Testes de Sensibilidade Microbiana , beta-Lactamases , beta-Lactamases/metabolismo , Citometria de Fluxo/métodos , Proteínas de Bactérias/metabolismo , Humanos , Testes de Sensibilidade Microbiana/métodos , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Antibacterianos/farmacologia , Sensibilidade e Especificidade , Carbapenêmicos/farmacologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-36943338

RESUMO

A Gram-stain-negative strain, designated BR102T, isolated from a soil sample in Brazil was characterized by a polyphasic approach. Comparative 16S rRNA gene sequences indicated that strain BR102T belonged to the genus Citrobacter. The recN- and whole-genome-based phylogeny, and multilocus sequence analysis based on concatenated partial fusA, leuS, pyrG and rpoB sequences strongly supported a clade encompassing strain BR102T and a strain from public database that was distinct from currently recognized species of the genus Citrobacter. Average nucleotide identity and digital DNA-DNA hybridization values between strain BR102T and the closest relative Citrobacter freundii ATCC 8090T were 91.8 and 48.8 %, respectively. The ability to metabolize different compounds further discriminated strain BR102T from other closely related species of the genus Citrobacter. The novel variants bla CMY-179 and qnrB97, which encoded a CMY-2-like ß-lactamase and a QnrB-type protein, respectively, were identified in strain BR102T. BR102T was resistant to ampicillin, amoxicillin/clavulanate and cefoxitin. The DNA G+C content of strain BR102T is 51.3 mol%. Based on these results, strain BR102T represents a novel species of the genus Citrobacter, for which the name Citrobacter meridianamericanus sp. nov. is proposed. The type strain is BR102T (=MUM 22.55T=IMI 507229T).


Assuntos
Citrobacter , Genes Bacterianos , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , Ácidos Graxos/química , DNA Bacteriano/genética , Filogenia , Composição de Bases , Técnicas de Tipagem Bacteriana , Solo
4.
Environ Microbiol ; 24(10): 4702-4713, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35726894

RESUMO

The expansion of mcr-carrying bacteria is a well-recognized public health problem. Measures to contain mcr spread have mainly been focused on the food-animal production sector. Nevertheless, the spread of MCR producers at the environmental interface particularly driven by the increasing population of gulls in coastal cities has been less explored. Occurrence of mcr-carrying Escherichia coli in gull's colonies faeces on a Portuguese beach was screened over 7 months. Cultural, molecular and genomic approaches were used to characterize their diversity, mcr plasmids and adaptive features. Multidrug-resistant mcr-1-carrying E. coli were detected for 3 consecutive months. Over time, multiple strains were recovered, including zoonotic-related pathogenic E. coli clones (e.g. B2-ST131-H22, A-ST10 and B1-ST162). Diverse mcr-1 genetic environments were mainly associated with ST2/ST4-HI2 (ST10, ST131, ST162, ST354 and ST4204) but also IncI2 (ST12990) plasmids or in the chromosome (ST656). Whole-genome sequencing revealed enrichment of these strains on antibiotic resistance, virulence and metal tolerance genes. Our results underscore gulls as important spreaders of high-priority bacteria and genes that may affect the environment, food-animals and/or humans, potentially undermining One-Health strategies to reduce colistin resistance.


Assuntos
Charadriiformes , Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Antibacterianos/farmacologia , Células Clonais , Colistina , Farmacorresistência Bacteriana/genética , Escherichia coli , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Gado , Testes de Sensibilidade Microbiana , Plasmídeos/genética
5.
Environ Microbiol ; 23(12): 7563-7577, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34327794

RESUMO

Expansion of mcr-carrying Enterobacteriaceae (MCR-E) is a well-recognized problem affecting animals, humans and the environment. Ongoing global control actions involve colistin restrictions among food-animal production, but their impact on poultry-derived products is largely unknown, justifying comprehensive farm-to-fork studies. Occurrence of MCR-E among 53 chicken-meat batches supplied from 29 Portuguese farms shortly after colistin withdrawal was evaluated. Strains (FT-IR/MLST/WGS), mcr plasmids and their adaptive features were characterized by cultural, molecular and genomic approaches. We found high rates of chicken-meat batches (80%-100% - 4 months; 12% - the last month) with multiple MDR + mcr-1-carrying Escherichia coli (Ec-including ST117 and ST648-Cplx) and Klebsiella pneumoniae (Kp-ST147-O5:K35) clones, some of them persisting over time. The mcr-1 was located in the chromosome (Ec-ST297/16-farms) or dispersed IncX4 (Ec-ST602/ST6469/5-farms), IncHI2-ST2/ST4 (Ec-ST533/ST6469/5 farms and Kp-ST147/6-farms) or IncI2 (Ec-ST117/1-farm) plasmids. WGS revealed high load and diversity in virulence, antibiotic resistance and metal tolerance genes. This study supports colistin withdrawal potential efficacy in poultry production and highlights both poultry-production chain as a source of mcr-1 and the risk of foodborne transmission to poultry-meat consumers. Finally, in the antibiotic reduction/replacement context, other potential co-selective pressures (e.g., metals-Cu as feed additives) need to be further understood to guide concerted, effective and durable actions under 'One Health' perspective.


Assuntos
Colistina , Proteínas de Escherichia coli , Animais , Antibacterianos/farmacologia , Galinhas , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Proteínas de Escherichia coli/genética , Fazendas , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Plasmídeos/genética , Portugal , Aves Domésticas , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Microb Pathog ; 155: 104920, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33930418

RESUMO

The presence of specific virulence features conditions severe forms of urinary tract disease, but the frequency and distribution of these highly virulent extraintestinal pathogenic Escherichia coli strains in animals and humans is unclear. We used whole genome sequencing, comparative genomics, histological and clinical data to characterize the genetic basis for pathogenesis and origin of E. coli Ec_151217, a strain (B2, ST83, O83:H5:K5) that caused an extremely aggressive upper urinary tract infection (UTI) in a cat. We show that Ec_151217 and 52% of other highly related ST83 genomes (O6 and O83) identified from different animal species and human infections carry two copies of the hemolysin A operon, though this duplication is infrequent (~1%) among closed ExPEC genomes from multiple sources. Our data enlarges the list of E. coli genetic backgrounds carrying hlyA operon duplication which is potentially involved in severity of UTI, and demonstrates that it seems to occur infrequently amongst ExPEC. Its identification in E. coli lineages (diverse ST83 serotypes) of potential animal-human transmission is of concern and anticipates the need to screen larger collections.


Assuntos
Infecções por Escherichia coli , Escherichia coli Extraintestinal Patogênica , Infecções Urinárias , Animais , Gatos , Escherichia coli/genética , Infecções por Escherichia coli/veterinária , Escherichia coli Extraintestinal Patogênica/genética , Humanos , Filogenia
7.
Eur J Clin Microbiol Infect Dis ; 39(12): 2471-2475, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32643025

RESUMO

The spread of multidrug-resistant (MDR) Klebsiella pneumoniae in the nosocomial setting represents a big challenge to infection control teams. We have recently developed a simple spectroscopic-based method with excellent accuracy, turnaround time and cost-effectiveness (Rodrigues et al. mSystems 2020) for bacterial typing. Here, we applied our method in a real clinical context to support early identification of an outbreak involving KPC-3-producing K. pneumoniae ST147 isolates. Our results further support that attenuated total reflectance Fourier transform infrared (FT-IR) spectroscopy can provide enough information to support early and adequate infection control measures and therapeutic choices in the context of nosocomial outbreaks and hospital surveillance.


Assuntos
Proteínas de Bactérias/genética , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , beta-Lactamases/genética , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Técnicas de Tipagem Bacteriana , Carbapenêmicos/farmacologia , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/metabolismo , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Portugal/epidemiologia , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Eur J Clin Microbiol Infect Dis ; 38(3): 427-448, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30483997

RESUMO

The need to identify highly related bacterial strains is ancient in clinical, industrial, or environmental microbiology. Strategies based on different phenotypic and genotypic principles have been used since the early 1930s with variable outcomes and performances, accompanying the evolution of bacterial features' knowledge as well as technologies, instruments, and data analysis tools. Today, more than ever, the implementation of bacterial typing methods that combine a high reliability and accuracy with a rapid, low-cost, and user-friendly performance is highly desirable, especially for clinical microbiology. FT-IR developments for bacterial discrimination at the infra-species level settled on the identification of bacterial groups previously defined by phenotypic or genotypic typing methods. Therefore, this review provides a brief historical overview of main bacterial strain typing methods, and a comprehensive analysis of the fundamentals and applications of Fourier transform infrared spectroscopy, a phenotypic-based method with potential for routine strain typing. The different studies on FT-IR-based strain typing of diverse Gram-negative and Gram-positive bacterial species are discussed in light of genotypic, phenotypic, and biochemical aspects, in order to definitively give this methodology credit to be widely accepted by microbiologists. Importantly, the discriminatory biochemical fingerprints observed on FT-IR spectra have been consistently correlated with sugar-based coating structures that besides reflecting strain variation are also of high relevance for the specificity in pathogen-host interactions. Thus, FT-IR-based bacterial typing might not only be useful for quick and reliable strain typing but also to help understanding the diversity, evolution, and host adaptation factors of key bacterial pathogens or subpopulations.


Assuntos
Bactérias/classificação , Técnicas de Tipagem Bacteriana/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Bactérias/química , Bactérias/genética , Genótipo , Polissacarídeos Bacterianos/análise , Sorogrupo , Especificidade da Espécie
9.
Emerg Infect Dis ; 24(4): 762-766, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29553327

RESUMO

We describe a hospital-based outbreak caused by multidrug-resistant, Klebsiella pneumoniae carbapenemase 3-producing, mcr-1-positive K. pneumoniae sequence type 45 in Portugal. mcr-1 was located in an IncX4 plasmid. Our data highlight the urgent need for systematic surveillance of mcr-1 to support adequate therapeutic choices in the nosocomial setting.


Assuntos
Proteínas de Bactérias/genética , Hospitalização , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , beta-Lactamases/genética , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Feminino , História do Século XXI , Humanos , Infecções por Klebsiella/história , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Portugal/epidemiologia
10.
Bioorg Chem ; 79: 341-349, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29807207

RESUMO

The restricted number of antibiotics to treat infections caused by common multidrug resistant bacterial pathogens in the clinical setting demands a continuous search for new molecules with antibacterial properties. Bacterial iron deprivation represents a promising alternative, being iron chelators an attractive class for drug design in which particular compounds seem to have antibacterial effect. In this work, we report the synthesis and characterization of a new fluorescent 3-hydroxy-4-pyridinone (3,4-HPO) iron chelator functionalized with a carboxyrosamine fluorophore (MRB20). The antibacterial activity of MRB20 was assessed against representative strains from clinically relevant Gram-positive and Gram-negative bacterial species and further compared with the inhibitory effect of a set of structurally related iron chelators including Deferiprone (1,2-dimethyl-3-hydroxy-4-pyridinone). Compounds exhibiting a promising minimal inhibitory concentration (MIC < 10 mg/L) were further tested against a wider range of bacterial genera and species (Staphylococcus spp. Enterococcus spp. Listeria monocytogenes, Bacillus spp.), including multidrug resistant bacteria. With the exception of the novel compound (MRB20), all chelators inhibited the strains assayed at very high concentrations [minimum inhibitory concentrations (MIC) ranging from 70 mg/L to >180 mg/L]. MRB20 revealed a good antibacterial activity (6.7-13.2 mg/L) against Gram-positive strains from different genera and species, including clinically relevant species (Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecium, Enterococcus faecalis), which might be eventually compatible with a therapeutic application or as adjuvant.


Assuntos
Antibacterianos/farmacologia , Corantes Fluorescentes/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Quelantes de Ferro/farmacologia , Rodaminas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Compostos Heterocíclicos com 3 Anéis/síntese química , Compostos Heterocíclicos com 3 Anéis/química , Quelantes de Ferro/síntese química , Quelantes de Ferro/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Rodaminas/síntese química , Rodaminas/química , Relação Estrutura-Atividade
11.
Int J Syst Evol Microbiol ; 67(9): 3513-3517, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28857032

RESUMO

A Gram-stain-negative strain, A60T, isolated from a water well sample in Portugal, was characterized phenotypically, genotypically and phylogenetically. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain A60T belonged to the genus Citrobacter, and recN gene phylogeny revealed one strongly supported clade encompassing strain A60T and 13 other strains from public databases, distinct from currently recognized species of the genus Citrobacter. Furthermore, multilocus sequence analysis (MLSA) based on concatenated partial fusA, leuS, pyrG and rpoB sequences confirmed the classification obtained with the recN sequence. In silico genomic comparisons, including average nucleotide identity (ANI) and the genome-to-genome distance calculator (GGDC), showed 94.6 % and 58.4 % identity to the closest relative Citrobacter freundii ATCC 8090T, respectively. The ability to metabolize different compounds further discriminated strain A60T from other species of the genus Citrobacter. The G+C content of strain A60T is 52.0 %. The results obtained support the description of a novel species within the genus Citrobacter, for which the name Citrobacter portucalensis sp. nov. is proposed, with the type strain A60T (=DSM 104542T=CECT 9236T).


Assuntos
Citrobacter/classificação , Filogenia , Microbiologia da Água , Poços de Água , Técnicas de Tipagem Bacteriana , Composição de Bases , Citrobacter/genética , Citrobacter/isolamento & purificação , DNA Bacteriano/genética , Genes Bacterianos , Tipagem de Sequências Multilocus , Portugal , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Antimicrob Agents Chemother ; 59(10): 5951-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26169406

RESUMO

To gain insights into the diversification trajectories of qnrB genes, a phylogenetic and comparative genomics analysis of these genes and their surrounding genetic sequences was performed. For this purpose, Citrobacter sp. isolates (n = 21) and genome or plasmid sequences (n = 56) available in public databases harboring complete or truncated qnrB genes were analyzed. Citrobacter species identification was performed by phylogenetic analysis of different genotypic markers. The clonal relatedness among isolates, the location of qnrB genes, and the genetic surroundings of qnrB genes were investigated by pulsed-field gel electrophoresis (PFGE), S1-/I-CeuI-PFGE and hybridization, and PCR mapping and sequencing, respectively. Identification of Citrobacter isolates was achieved using leuS and recN gene sequences, and isolates characterized in this study were diverse and harbored chromosomal qnrB genes. Phylogenetic analysis of all known qnrB genes revealed seven main clusters and two branches, with most of them included in two clusters. Specific platforms (comprising pspF and sapA and varying in synteny and/or identity of other genes and intergenic regions) were associated with each one of these qnrB clusters, and the reliable identification of all Citrobacter isolates revealed that each platform evolved in different recognizable (Citrobacter freundii, C. braakii, C. werkmanii, and C. pasteurii) and putatively new species. A high identity was observed between some of the platforms identified in the chromosome of Citrobacter spp. and in different plasmids of Enterobacteriaceae. Our data corroborate Citrobacter as the origin of qnrB and further suggest divergent evolution of closely related qnrB genes/platforms in particular Citrobacter spp., which were delineated using particular genotypic markers.


Assuntos
Cromossomos Bacterianos/química , Citrobacter/genética , Farmacorresistência Bacteriana/genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Filogenia , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Sequência de Bases , Evolução Biológica , Mapeamento Cromossômico , Cromossomos Bacterianos/metabolismo , Citrobacter/classificação , Citrobacter/efeitos dos fármacos , Citrobacter/metabolismo , Eletroforese em Gel de Campo Pulsado , Infecções por Enterobacteriaceae/microbiologia , Fluoroquinolonas/farmacologia , Genótipo , Humanos , Dados de Sequência Molecular , Família Multigênica , Plasmídeos/química , Plasmídeos/metabolismo , Análise de Sequência de DNA
13.
Antimicrob Agents Chemother ; 59(5): 2904-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25691645

RESUMO

We describe the genetic background of bla(TEM-4) and the complete sequence of pRYC11::bla(TEM-4), a mosaic plasmid that is highly similar to pKpQIL-like variants, predominant among TEM-4 producers in a Spanish hospital (1990 to 2004), which belong to Klebsiella pneumoniae and Escherichia coli high-risk clones responsible for the current spread of different antibiotic resistance genes. Predominant populations of plasmids and host adapted clonal lineages seem to have greatly contributed to the spread of resistance to extended-spectrum cephalosporins.


Assuntos
Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Dados de Sequência Molecular
14.
J Antimicrob Chemother ; 70(4): 1016-20, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25630639

RESUMO

OBJECTIVES: The present study was designed to provide a snapshot on carbapenemase-producing Pseudomonas aeruginosa (n=11) and Acinetobacter baumannii (n=7) isolates in hospitalized patients (November 2011, January-March 2012) from two main hospitals in Bucharest, south Romania. METHODS: Clonality among isolates was established by PFGE, MLST and Fourier transform infrared spectroscopy. Carbapenemases were screened by the Blue-Carba test, PCR and sequencing. Transferability of blaOXA-23 was tested by conjugation and plasmid typing (number, size and identity) was assessed by S1-PFGE, replicon typing, hybridization and PCR mapping. RESULTS: All P. aeruginosa isolates carried chromosomally located blaVIM-2, associated with a common class 1 integron (aacA7-blaVIM-2) or an atypical configuration (aacA7-blaVIM-2-dfrB5-tniC). These isolates belonged to unusual lineages; mostly ST233 disseminated in one hospital unit, with ST364 and ST1074 also being detected. A. baumannii isolates carried blaOXA-23 in Tn2008, which was found truncating a TnaphA6 transposon located in a common 60 kb GR6 (aci6) pABKp1-like conjugative plasmid in highly related CC92 clones (ST437, ST764 and ST765), where CC stands for clonal complex. CONCLUSIONS: Our results show the spread of VIM-2-producing P. aeruginosa and OXA-23-producing A. baumannii clinical isolates in two hospitals from Bucharest and highlight a peculiar population structure in this Eastern European country. Also, we demonstrate the dissemination of a common and conjugative aci6 pABKp1-like plasmid scaffold in different A. baumannii clones and we report the first known identification of Tnaph6-carrying pACICU2-like plasmids in Europe.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/enzimologia , Proteínas de Bactérias/metabolismo , Infecção Hospitalar/microbiologia , Genótipo , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , beta-Lactamases/metabolismo , Acinetobacter baumannii/classificação , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Proteínas de Bactérias/genética , Conjugação Genética , Eletroforese em Gel de Campo Pulsado , Transferência Genética Horizontal , Hospitais , Humanos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Plasmídeos/análise , Plasmídeos/classificação , Reação em Cadeia da Polimerase , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Romênia , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Lactamases/genética
15.
Int J Med Microbiol ; 304(8): 1100-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25190354

RESUMO

The aim of this study was to characterize by a multi-level approach extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae isolates other than E. coli from Portuguese hospitals. Eighty-eight ESBL-producing clinical isolates (69 Klebsiella pneumoniae, 13 Enterobacter cloacae complex, 3 Klebsiella oxytoca, 1 Enterobacter asburiae, 1 Proteus mirabilis and 1 Serratia marcescens) recovered from hospitals located in the North (A) or Centre (B, C) regions during two time periods (2006-7 and 2010) were analyzed. Standard methods were used for bacterial identification, antibiotic susceptibility testing, ESBL characterization, clonal (PFGE, MLST) and plasmid (S1-PFGE, I-CeuI-PFGE, replicon typing, hybridization) analysis. Isolates produced mostly CTX-M-15 (47%) or SHV-12 (30%), and less frequently other SHV- (15%; SHV-2, -5, -28, -55, -106) or TEM- (9%; TEM-10, -24, -199)-types, with marked local and temporal variations. The increase of CTX-M-15 and diverse SHV ESBL-types observed in Hospital A was associated with the amplification of multidrug-resistant (MDR) K. pneumoniae epidemic clones (ST15, ST147, ST336). SHV-12 and TEM-type ESBLs were mostly identified in diverse isolates of different Enterobacteriaceae species in Hospitals B and C in 2006-7. Particular plasmid types were linked to blaCTX-M-15 (IncR or non-typeable plasmids), blaSHV-12 (IncR or IncHI2), blaSHV-28/-55/-106 (IncFIIK1 or IncFIIK5), blaTEM-10 (IncL/M) or blaTEM-24 (IncA/C), mostly in epidemic clones. In our country, the amplification of CTX-M-15 and diverse SHV-type ESBL among non-E. coli Enterobacteriaceae is linked to international MDR K. pneumoniae clones (ST15, ST147, ST336) and plasmid types (IncR, IncFIIK). Furthermore, we highlight the potential of IncFIIK plasmids (here firstly associated with blaSHV-2/-28/-55/-106) to disseminate as antibiotic resistance plasmids.


Assuntos
Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/classificação , Enterobacteriaceae/enzimologia , beta-Lactamases/metabolismo , DNA Bacteriano/química , DNA Bacteriano/genética , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Epidemias , Genótipo , Hospitais , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Tipagem Molecular , Plasmídeos/análise , Portugal/epidemiologia , Análise de Sequência de DNA
16.
Front Microbiol ; 15: 1365011, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38746750

RESUMO

The rise of antibiotic resistance in the food chain is influenced by the use of antimicrobial agents, such as antibiotics, metals, and biocides, throughout the entire farm-to-fork continuum. Besides, non-clinical reservoirs potentially contribute to the transmission of critical pathogens such as multidrug-resistant (MDR) Klebsiella pneumoniae. However, limited knowledge exists about the population structure and genomic diversity of K. pneumoniae circulating in conventional poultry production. We conducted a comprehensive characterization of K. pneumoniae across the whole chicken production chain (7 farms; 14 flocks + environment + meat, 56 samples; 2019-2022), exploring factors beyond antibiotics, like copper and quaternary ammonium compounds (QACs). Clonal diversity and adaptive features of K. pneumoniae were characterized through cultural, molecular (FT-IR), and whole-genome-sequencing (WGS) approaches. All except one flock were positive for K. pneumoniae with a significant increase (p < 0.05) from early (n = 1/14) to pre-slaughter (n = 11/14) stages, most (n = 6/7) persisting in chicken meat batches. Colistin-resistant K. pneumoniae rates were low (4%-n = 1/24 positive samples), while most samples carried MDR strains (67%-n = 16/24) and copper-tolerant isolates (63%-n = 15/24, with sil and pco gene clusters; MICCuSO4 ≥ 16 mM), particularly at pre-slaughter. Benzalkonium chloride consistently exhibited activity against K. pneumoniae (MIC/MBC range = 4-64 mg/L) from representative strains independently of the presence or absence of genes linked to QACs tolerance. A polyclonal K. pneumoniae population, discriminated by FT-IR and WGS, included various lineages dispersed throughout the chicken's lifecycle at the farm (ST29-KL124, ST11-KL106, ST15-KL19, ST1228-KL38), until the meat (ST1-KL19, ST11-KL111, ST6405-KL109, and ST6406-CG147-KL111), or over years (ST631-49 KL109, ST6651-KL107, ST6406-CG147-KL111). Notably, some lineages were identical to those from human clinical isolates. WGS also revealed F-type multireplicon plasmids carrying sil + pco (copper) co-located with qacEΔ1 ± qacF (QACs) and antibiotic resistance genes like those disseminated in humans. In conclusion, chicken farms and their derived meat are significant reservoirs for diverse K. pneumoniae clones enriched in antibiotic resistance and metal tolerance genes, some exhibiting genetic similarities with human clinical strains. Further research is imperative to unravel the factors influencing K. pneumoniae persistence and dissemination within poultry production, contributing to improved food safety risk management. This study underscores the significance of understanding the interplay between antimicrobial control strategies and non-clinical sources to effectively address the spread of antimicrobial resistance.

17.
PeerJ ; 12: e17673, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39131622

RESUMO

Whole genome sequencing (WGS) has become a vital tool in clinical microbiology, playing an important role in outbreak investigations, molecular surveillance, and identification of bacterial species, resistance mechanisms and virulence factors. However, the complexity of WGS data presents challenges in interpretation and reporting, requiring tailored strategies to enhance efficiency and impact. This study explores the diverse needs of key stakeholders in healthcare, including clinical management, laboratory work, public surveillance and epidemiology, infection prevention and control, and academic research, regarding WGS-based reporting of clinically relevant bacterial species. In order to determine preferences regarding WGS reports, human-centered design approach was employed, involving an online survey and a subsequent workshop with stakeholders. The survey gathered responses from 64 participants representing the above mentioned healthcare sectors across geographical regions. Key findings include the identification of barriers related to data accessibility, integration with patient records, and the complexity of interpreting WGS results. As the participants designed their ideal report using nine pre-defined sections of a typical WGS report, differences in needs regarding report structure and content across stakeholders became evident. The workshop discussions further highlighted the need to feature critical findings and quality metrics prominently in reports, as well as the demand for flexible report designs. Commonalities were observed across stakeholder-specific reporting templates, such as the uniform ranking of certain report sections, but preferences regarding the depth of content within these sections varied. Using these findings, we suggest stakeholder-specific structures which should be considered when designing customized reporting templates. In conclusion, this study underscores the importance of tailoring WGS-based reports of clinically relevant bacteria to meet the distinct needs of diverse healthcare stakeholders. The evolving landscape of digital reporting increases the opportunities with respect to WGS reporting and its utility in managing infectious diseases and public health surveillance.


Assuntos
Sequenciamento Completo do Genoma , Humanos , Genoma Bacteriano/genética , Inquéritos e Questionários
18.
J Antimicrob Chemother ; 68(10): 2245-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23719233

RESUMO

OBJECTIVES: The spread of ESBL-producing Enterobacteriaceae among food animals/products has raised concerns about their possible transmission through the food chain. We aimed to characterize piggeries (pigs, piggery environments) as reservoirs of TEM-52- and CTX-M-encoding plasmids and clones. METHODS: Forty-three samples from five Portuguese intensive production farms were studied (2006-07). Twenty-two ESBL-producing (13 TEM-52, 6 CTX-M-32, 3 CTX-M-1) Escherichia coli isolates from healthy pigs, feed and liquid manure were further characterized. Standard methods were used for clonal (PFGE, MLST) and plasmid (S1-PFGE, replicon typing, pMLST, RFLP) analysis. PCR and sequencing were used for analysis of blaCTX-M genetic context and plasmid-mediated quinolone resistance genes. RESULTS: TEM-52 (n = 13/22; 59%), CTX-M-32 (n = 6/22; 27%) and CTX-M-1 (n = 3/22; 14%) were identified in feed (36%), swine faeces (36%), swine hide (9%) and liquid manure (18%) at different farms. Diverse phylogenetic groups and clones were identified among TEM-52 (7 A, 3 B1, 2 B2, 1 D; 8 clones)-producing, CTX-M-1 (1 A, 1 B1, 1 D; 3 clones)-producing and CTX-M-32 (4 A, 2 B1; 4 clones)-producing isolates. However, the ST10 clonal complex was frequent among TEM-52 (n = 6) and CTX-M-32 (n = 3) producers. blaTEM-52 and blaCTX-M-1/-32 genes were identified within epidemic IncI1/ST3 and IncN/ST1 plasmid variants, respectively. CONCLUSIONS: We report for the first time a piggery reservoir for blaTEM-52. The spread of blaTEM-52 and blaCTX-M-1/-32 within and/or between different piggeries was mostly associated with epidemic plasmids and clones previously identified in humans and other animal hosts in different EU countries, highlighting possible distribution along the food chain.


Assuntos
Infecções por Escherichia coli/veterinária , Escherichia coli/genética , Transferência Genética Horizontal , Plasmídeos , beta-Lactamases/genética , Animais , Eletroforese em Gel de Campo Pulsado , Microbiologia Ambiental , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Genótipo , Tipagem de Sequências Multilocus , Polimorfismo de Fragmento de Restrição , Portugal , Suínos , Resistência beta-Lactâmica
19.
BMC Microbiol ; 13: 144, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23800205

RESUMO

BACKGROUND: Phylogenetic group D Escherichia coli clones (ST69, ST393, ST405) are increasingly reported as multidrug resistant strains causing extra-intestinal infections. We aim to characterize inter- and intraclonal diversity of a broad sample (isolates from different geographic locations and origins with variable antibiotic resistance profiles, 1980-2010) and their ability to adhere and form biofilm by both a modified quantitative biofilm producing assay and Field Emission Scanning Electron Microscopy (FESEM). RESULTS: High virulence scores were observed among ST69 (median 14/range 9-15) and ST393 (median 14/range 8-15) clones, particularly enriched in pap alleles, iha, kpsMTII-K5 and ompT, in contrast with ST405 (median 6/range 2-14) isolates, exhibiting frequently fyuA, malX and traT. All ST69 and ST393 and only two ST405 isolates were classified as ExPEC. Biofilm production was detected in two non-clinical ST69 and three ST393 isolates from different origins showing variable virulence profiles. Within each clonal group, and despite the high diversity of PFGE-types observed, isolates from different countries and recovered over large periods of time were clustered in a few groups sharing common virulence gene profiles among ST69 (n = 10 isolates) and ST393 (n = 9 isolates) (fimH-iha-iutA-kpsMTII-K5-(traT)-sat-(ompT)-papA-papEF-papGII-papC) or ST405 (n = 6 isolates) (fimH-traT-fyuA-malX). CONCLUSIONS: This study highlights the circulation of highly transmissible ST69, ST393 and ST405 variants among different settings. Biofilm production seems not to be directly correlated with their epidemiological success.


Assuntos
Biofilmes/crescimento & desenvolvimento , Escherichia coli/classificação , Escherichia coli/fisiologia , Variação Genética , Análise por Conglomerados , Eletroforese em Gel de Campo Pulsado , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Genótipo , Humanos , Microscopia Eletrônica de Varredura , Tipagem Molecular , Fatores de Virulência/genética
20.
J Glob Antimicrob Resist ; 34: 195-198, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37468064

RESUMO

OBJECTIVES: A higher diversity of species, clones and genes have been increasingly implicated in carbapenemases spread, though the mobile genetic elements responsible for their acquisition and dispersion at local and global levels are less explored, particularly in species other than Klebsiella pneumoniae or Escherichia coli. We aim to explain the emergence of NDM-1 and KPC-3 carbapenemases in a Kluyvera cryocrescens isolate, and to shed light on the heterogeneity of genetic platforms and acquisition routes of blaNDM-1 in diverse Enterobacterales species in Portugal. METHODS: A KPC-3 and NDM-1-producing K. cryocrescens colonizing a hospitalized patient in 2019 was characterized by whole-genome sequencing and antibiotic resistance profiling following standard methods. Conjugative transfer of carbapenemases genes was assessed by filter mating. Plasmids were reconstructed with in silico and in vitro approaches. blaNDM-1 genetic context was compared with that of diverse NDM-1-producing Enterobacterales species, previously described in Portugal. RESULTS: K. cryocrescens K629 showed a multidrug resistance profile. Resistance gene blaKPC-3 was harboured by a Tn4401d transposon within a worldwide-spread IncN-ST15 plasmid (pKLU-KPC3), whereas blaNDM-1 was located in a Tn3000 within a non-typeable mosaic plasmid (pKLU-NDM1). The heterogeneous blaNDM-1 genetic platforms and variable plasmid backbones identified in various Enterobacterales species suggested multiple introductions of blaNDM-1 in Portugal, mediated by variable insertion sequences. CONCLUSIONS: We report the convergence of KPC-3 and NDM-1 in K. cryocrescens and the variable dissemination modes of these carbapenemases in different Enterobacterales species, underlining the need to track down genetic platforms responsible for carbapenemases diffusion.


Assuntos
Escherichia coli , Heterogeneidade Genética , Humanos , Portugal , Escherichia coli/genética
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