RESUMO
Burkholderia contaminans, a species of the Burkholderia cepacia complex-prevalent in certain Latin-American and European countries-can cause chronic pulmonary infection in persons with cystic fibrosis. Our aim was to gain insights into long-term lung infections with a focus on correlating how bacterial phenotypic traits in the chronic infection impact on patients' clinical outcome. Genotypic characteristics of 85 B. contaminans isolates recovered from 70 patients were investigated. For 16 of those patients, the clinical status and bacterial phenotypic characteristics, e.g. several virulence factors, phenotypic variants, and the antimicrobial susceptibility pattern, were evaluated. Two clones were found in the whole bacterial population: (i) the multiresistant ST 872 PCR-recA-RFLP-HaeIII-K-pattern clone, which carries a pathogenic island homologous to BcenGI11 of B. cenocepacia J2315, and (ii) the ST 102 PCR-recA-RFLP-HaeIII-AT-pattern clone. The emergence of certain bacterial phenotypes in the chronic infection such as the nonmucoid phenotype, small colony variants, brownish pigmented colonies, and hypermutators, proved to be, together with coinfection with Pseudomonas aeruginosa, the possible markers of more challenging infections and poor prognosis. The presence of cocolonizers and the bacterial phenotypes that are especially adapted to persist in long-term respiratory tract infections have a crucial role in patients' clinical outcomes.
Assuntos
Infecções por Burkholderia , Complexo Burkholderia cepacia , Fibrose Cística , Pneumonia , Humanos , Infecção Persistente , Fibrose Cística/complicações , Fibrose Cística/microbiologia , Pulmão/microbiologia , Fenótipo , Infecções por Burkholderia/microbiologiaRESUMO
INTRODUCTION: The Burkholderia cepacia complex (BCC) bacteria are opportunistic pathogens that cause nosocomial infections and are especially dangerous for cystic fibrosis (CF) patients. Burkholderia contaminans is an emerging BCC species isolated from CF patients that also occurs as a contaminant in pharmaceutical and personal care products, sometimes linking it with outbreaks. METHODOLOGY: A total of 55 B. contaminans isolates from CF and non-CF patients in Argentina were identified by recA sequencing and MALDI TOF MS. A standardized Pulsed Field Gel Electrophoresis (PFGE) protocol was set up in order to assess genetic diversity, outbreak investigations, and possible clone persistence. RESULTS: All isolates were identified as B. contaminans by both MALDI-TOF MS and recA sequence analysis. PFGE has enabled us to compare and determine the genetic relationship between B. contaminans isolates. Isolates were distributed in different PFGE clusters with evidence of the presence and persistence of a clone, over a period of 3 years, in the same hospital. This large hospital outbreak involved CF and non-CF patients. Moreover, PFGE results showed a good correlation between sporadic or outbreak-related isolates and the available epidemiological information. CONCLUSIONS: These findings highlight the importance of B. contaminans in Argentina and provide evidence for encouraging the surveillance of highly transmissible clones. The study also contributes to global knowledge about B. contaminans infections.
Assuntos
Infecções por Burkholderia , Complexo Burkholderia cepacia , Fibrose Cística , Argentina/epidemiologia , Burkholderia , Infecções por Burkholderia/epidemiologia , Infecções por Burkholderia/microbiologia , Complexo Burkholderia cepacia/genética , Fibrose Cística/complicações , HumanosRESUMO
Burkholderia cenocepacia complex is associated with high transmissibility, virulence, and poor prognosis in cystic fibrosis (CF) patients. However, extrapulmonary infections are rare. We investigated the genome of a B. cenocepacia IIIA isolated from a liver abscess in a Brazilian CF patient and compared it to strain J2315. The whole genome was sequenced, and contigs were annotated by Rapid Annotation using Subsystem Technology. The Pathosystems Resource Integration Center was used to map antimicrobial and virulence genes. The genomic island (GIs) analysis was performed using two prediction methods, and the presence of putative plasmids and insertion sequences (ISs) was investigated. The isolate was confirmed as B. cenocepacia IIIA to ST-28 (ET12 lineage). A total of 64 genes for antimicrobial resistance and 47 genes related to virulence were identified. Among the virulence factors, there was a predominance of factors related to the invasion mechanism, to the flagellar biosynthesis protein, and to the RNA polymerase sigma factor for flagellar operon (cdpA). Two IS families (IS3 and IS5) and only one plasmid were found. On average 56 GIs were predicted by at least one of the methods applied. Comparative analysis showed resistance mechanisms and virulence factors revealing invasive determinants used by B. cenocepacia IIIA (ET12) in the process of disease spread to other infection sites (extrapulmonary) of highly virulent strains in CF patients.
Assuntos
Infecções por Burkholderia/microbiologia , Burkholderia cenocepacia/genética , Fibrose Cística/microbiologia , Genoma Bacteriano/genética , Abscesso Hepático/microbiologia , Adolescente , Brasil , Infecções por Burkholderia/complicações , Burkholderia cenocepacia/classificação , Burkholderia cenocepacia/isolamento & purificação , Fibrose Cística/complicações , Elementos de DNA Transponíveis/genética , DNA Bacteriano/genética , Farmacorresistência Bacteriana/genética , Feminino , Genes Bacterianos/genética , Ilhas Genômicas/genética , Humanos , Abscesso Hepático/complicações , Plasmídeos/genética , Fatores de Virulência/genéticaRESUMO
BACKGROUND: Burkholderia sensu stricto is comprised mainly of opportunistic pathogens. This group is widely distributed in the environment but is especially important in clinical settings. In Mexico, few species have been correctly identified among patients, most often B. cepacia is described. METHODOLOGY/PRINCIPAL FINDINGS: In this study, approximately 90 strains identified as B. cepacia with the VITEK2 system were isolated from two medical centers in Mexico City and analyzed by MLSA, BOX-PCR and genome analysis. The initial identification of B. cepacia was confirmed for many strains, but B. contaminans, B. multivorans and B. vietnamiensis were also identified among clinical strains for the first time in hospitals in Mexico. Additionally, the presence of B. pseudomallei was confirmed, and a novel species within the B. cepacia complex was documented. Several strains misidentified as B. cepacia actually belong to the genera Pseudomonas, Stenotrophomonas and Providencia. CONCLUSIONS/SIGNIFICANCE: The presence of different Burkholderia species in Mexico was confirmed. Correct identification of Burkholderia species is important to provide accurate treatment for immunosuppressed patients.
Assuntos
Infecções por Burkholderia/epidemiologia , Burkholderia/classificação , Burkholderia/genética , Burkholderia/isolamento & purificação , Infecções por Burkholderia/microbiologia , DNA Bacteriano/análise , Genoma Bacteriano , Humanos , México , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genéticaRESUMO
Low molecular weight protein tyrosine phosphatases (LMW-PTP) are ubiquitous enzymes found across a spectrum of genera from prokaryotes to higher eukaryotes. LMW-PTP belong to the Cys-based PTP class II protein family. Here, we show that LMW-PTP can be categorized into two different groups, referred as class II subdivision I (class II.I) and subdivision II (class II.II). Using BPtpA from the opportunistic pathogen Burkholderia cenocepacia, as a representative member of the LMW-PTP class II.I, we demonstrated that four conserved residues (W47, H48, D80, and F81) are required for enzyme function. Guided by an in silico model of BPtpA, we show that the conserved residues at α3-helix (D80 and F81) contribute to protein stability, while the other conserved residues in the W-loop (W47 and H48) likely play a role in substrate recognition. Overall, our results provide new information on LMW-PTP protein family and establish B. cenocepacia as a suitable model to investigate how substrates are recognized and sorted by these proteins.
Assuntos
Proteínas de Bactérias/metabolismo , Burkholderia cenocepacia/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Infecções por Burkholderia/microbiologia , Burkholderia cenocepacia/química , Humanos , Modelos Moleculares , Fosforilação , Proteínas Tirosina Fosfatases/químicaRESUMO
INTRODUCTION: Cystic fibrosis patients develop pulmonary exacerbations (PEs) that require intravenous treatment. The objective of this study was to determine the risk factors associated with PEs and establish the percentage of patients who failed to recover their lung function. POPULATION AND METHODS: Observational, retrospective, cohort study. The medical records of cystic fibrosis patients seen at Hospital de Niños Ricardo Gutiérrez in 2013 were reviewed. Patients were divided into group 1, with PE (Fuchs criteria), and group 2, without PE. Age, sex, p.F508del mutation, percentage of baseline forced expiratory volume in the first second, baseline body mass index Z-score, chronic Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and Burkholderia cepacia complex colonization (Leeds criteria), percentage of cystic fibrosis-related diabetes, and recovery of baseline forced expiratory volume in the first second were recorded. RESULTS: A total of 117 patients were included. Group 1: 50, group 2: 67 patients. PEs were associated with a lower body mass index Z-score (RR: 1.45; p = 0.002), p.F508del mutation (RR: 3.23; p = 0.05), and chronic Burkholderia cepacia complex (RR: 3.69; p = 0.002), Pseudomonas aeruginosa (RR: 1.89; p = 0.01) and methicillinresistant Staphylococcus aureus colonization (RR: 2.32; p = 0.002). Twenty-four percent of patients failed to recover their lung function. CONCLUSIONS: The presence of the p.F508del mutation, a poor nutritional status, and chronic colonization were the risk factors for exacerbation. A fourth of patients failed to recover their lung function.
Introducción. Los pacientes con fibrosis quística presentan exacerbaciones respiratorias (ER) que requieren tratamiento endovenoso. El objetivo fue determinar los factores de riesgo asociados a ER y obtener porcentaje de pacientes que no recuperaban su función pulmonar previa. Población y métodos. Observacional, de cohorte, retrospectivo. Se revisaron las historias clínicas de los pacientes con fibrosis quística atendidos en el Hospital de Niños Ricardo Gutiérrez durante 2013. Se dividieron en: grupo 1, con ER (criterios de Fuchs), y grupo 2, sin ER. Se registró edad, género, mutación p.F508del, porcentaje del volumen espiratorio forzado en el primer segundo basal, puntaje Z de índice de masa corporal basal, colonización crónica (criterios de Leeds) por Pseudomonas aeruginosa, Staphylococcus aureus meticilino resistente y complejo Burkholderia cepacia, porcentaje de diabetes relacionada con fibrosis quística y recuperación del volumen espiratorio forzado en el primer segundo basal. Resultados. Se incluyeron 117 pacientes. Grupo 1: 50; y grupo 2: 67 pacientes. Se asociaron a las ER: el menor puntaje Z de IMC (RR: 1,45; p = 0,002), p.F508del (RR: 3,23; p = 0,05) y colonización crónica por el complejo Burkholderia cepacia (RR: 3,69; p = 0,002), Pseudomonas aeruginosa (RR: 1,89; p = 0,01) y Staphylococcus aureus meticilino resistente (RR: 2,32; p = 0,002). El 24 % no recuperó su función pulmonar. Conclusiones. p.F508del, el bajo estado nutricional y la colonización crónica fueron factores de riesgo para exacerbación. Una cuarta parte de los pacientes no recuperó su función pulmonar previa.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/complicações , Pneumopatias/etiologia , Estado Nutricional , Adolescente , Infecções por Burkholderia/epidemiologia , Infecções por Burkholderia/microbiologia , Criança , Pré-Escolar , Estudos de Coortes , Fibrose Cística/genética , Feminino , Volume Expiratório Forçado , Humanos , Lactente , Pneumopatias/epidemiologia , Masculino , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologiaRESUMO
La espectrometría de masas (EM) (matrix assisted laser desorption ionization-time of flight) MALDI-TOF demostró ser una herramienta robusta para la identificación de numerosos grupos taxonómicos. No obstante, presenta limitaciones. Una ventaja clave de la técnica es la flexibilidad para la incorporación de espectros proteicos de microorganismos ausentes en la base de datos comercial. Dada la prevalencia de Burkholderia contaminans en los pacientes fibroquísticos en Argentina, y a que en ellos es crucial el diagnóstico microbiológico rápido y confiable, la EM MALDI-TOF surge como una herramienta estratégica. El objetivo del trabajo fue desarrollar una base de datos adicional con espectros peptídicos de aislamientos de referencia de B. contaminans. La misma demostró ser exitosa para la identificación del 97% de los aislamientos analizados. Por lo cual la EM MALDI-TOF con la base de datos extendida resultó ser una herramienta útil para la identificación y diferenciación de otras especies relacionadas a B. contaminans.
MALDI-TOF (matrix assisted laser desorption ionization-time of flight) mass spectrometry (MS) proved to be a robust tool for the identification of numerous taxonomic groups. However, it has limitations. A key advantage of this technique is the flexibility for the incorporation of protein profiles of microorganisms not included in the commercial database. Due to the prevalence of Burkholderia contaminans in fibrocystic patients in Argentina and the fact that rapid and reliable microbiological diagnosis is crucial in them, MALDI-TOF MS emerges as a strategic tool. The aim of this work was to develop an additional database with peptide spectra of reference isolates of B. contaminans. This database demonstrated to be successful for the identification of 97% of the isolates analyzed. Therefore, MALDI-TOF MS with the extended database was a useful tool for the identification and differentiation of other related species to B. contaminans.
Assuntos
Humanos , Bases de Dados Factuais , Técnicas Bacteriológicas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Burkholderia/isolamento & purificação , Especificidade da Espécie , Proteínas de Bactérias/análise , Algoritmos , Reprodutibilidade dos Testes , Infecções por Burkholderia/complicações , Infecções por Burkholderia/microbiologia , Burkholderia/classificação , Burkholderia/química , Fibrose Cística/complicações , Fibrose Cística/microbiologiaRESUMO
Burkholderia contaminans is a member of the Burkholderia cepacia complex (Bcc), a pathogen with increasing prevalence among cystic fibrosis (CF) patients and the cause of numerous outbreaks due to the use of contaminated commercial products. The antibiotic resistance determinants, particularly ß-lactamases, have been poorly studied in this species. In this work, we explored the whole genome sequence (WGS) of a B. contaminans isolate (FFH 2055) and detected four putative ß-lactamase-encoding genes. In general, these genes have more than 93% identity with ß-lactamase genes found in other Bcc species. Two ß-lactamases, a class A (Pen-like, suggested name PenO) and a class D (OXA-like), were further analyzed and characterized. Amino acid sequence comparison showed that Pen-like has 82% and 67% identity with B. multivorans PenA and B. pseudomallei PenI, respectively, while OXA-like displayed strong homology with class D enzymes within the Bcc, but only 22-44% identity with available structures from the OXA family. PCR reactions designed to study the presence of these two genes revealed a heterogeneous distribution among clinical and industrial B. contaminans isolates. Lastly, blaPenO gene was cloned and expressed into E. coli to investigate the antibiotic resistance profile and confers an extended-spectrum ß-lactamase (ESBL) phenotype. These results provide insight into the presence of ß-lactamases in B. contaminans, suggesting they play a role in antibiotic resistance of these bacteria.
Assuntos
Proteínas de Bactérias/genética , Complexo Burkholderia cepacia/enzimologia , Complexo Burkholderia cepacia/genética , Genoma Bacteriano/genética , beta-Lactamases/genética , Sequência de Aminoácidos , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Infecções por Burkholderia/microbiologia , Complexo Burkholderia cepacia/efeitos dos fármacos , Fibrose Cística/microbiologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Homologia de Sequência de Aminoácidos , beta-Lactamases/química , beta-Lactamases/metabolismoRESUMO
The correct identification of different genera and bacterial species is essential, especially when these bacteria cause infections and appropriate therapies need to be chosen. Bacteria belonging to the Burkholderia cepacia complex are considered important opportunistic pathogens, causing different types of infections in immunocompromised, principally in patients with cystic fibrosis. Twenty-one isolates were obtained from different soil samples and identified by sequencing of 16S rRNA, 23S rRNA, recA gene, MLST and by VITEK 2 and MALDI-TOF MS systems. Then, statistical analyses were performed. VITEK 2 and MALDI-TOF MS systems showed different bacterial genera. Sequencing of the 16S rRNA, 23S rRNA gene and amplification of recA gene showed that all the isolates belong to the B. cepacia complex. Sequencing of the recA gene showed a predominance of B. cenocepacia. The PCR of the recA gene showed a high specificity when it is necessary to identify the bacteria belonging to the B. cepacia complex in comparison with 16S and 23S rRNA genes sequencing. MLST analyzes showed a diversity of STs, which have not yet been correlated to the species. Phenotypic identification was not suitable for the identification of these pathogens since in many cases different genera have been reported, including identification by using MALDI-TOF MS.
Assuntos
Técnicas de Tipagem Bacteriana/métodos , Complexo Burkholderia cepacia/classificação , Complexo Burkholderia cepacia/genética , Complexo Burkholderia cepacia/isolamento & purificação , Filogenia , Microbiologia do Solo , Proteínas de Bactérias/genética , Infecções por Burkholderia/microbiologia , Fibrose Cística/microbiologia , DNA Bacteriano/genética , Tipagem de Sequências Multilocus/métodos , Infecções Oportunistas/microbiologia , Fenótipo , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Recombinases Rec A/genética , Análise de Sequência de DNA , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodosRESUMO
MALDI-TOF (matrix assisted laser desorption ionization-time of flight) mass spectrometry (MS) proved to be a robust tool for the identification of numerous taxonomic groups. However, it has limitations. A key advantage of this technique is the flexibility for the incorporation of protein profiles of microorganisms not included in the commercial database. Due to the prevalence of Burkholderia contaminans in fibrocystic patients in Argentina and the fact that rapid and reliable microbiological diagnosis is crucial in them, MALDI-TOF MS emerges as a strategic tool. The aim of this work was to develop an additional database with peptide spectra of reference isolates of B. contaminans. This database demonstrated to be successful for the identification of 97% of the isolates analyzed. Therefore, MALDI-TOF MS with the extended database was a useful tool for the identification and differentiation of other related species to B. contaminans.