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1.
New Microbes New Infect ; 39: 100829, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33473321

RESUMEN

An immunocompetent patient without a history of recent travel or animal exposure developed persistent abdominal bloating and cramps without diarrhoea or fever. Negative additional investigations excluded gastritis, infectious colitis, inflammatory bowel disease and neoplasia, but routine stool culture detected a Campylobacter-like organism. The isolate was obtained with use of a polycarbonate filter technique, emphasizing the importance of culture to support and validate the occurrence of emerging and new bacterial enteric pathogens. The ensuing extensive laboratory examinations proved challenging in identifying this potential pathogen. Phylogenetic marker analysis based on the 16S ribosomal RNA and rpoB gene sequences revealed that the isolate was most closely related to Arcobacter lanthieri and Arcobacter faecis. Subsequent analysis of a draft whole genome sequence assigned the isolate to A. lanthieri. We report the presence of five virulence genes, cadF, ciaB, mviN, hecA and iroE, indicating a possible pathogenic nature of this organism. This case demonstrated the importance of the use of agnostic methods for the detection of emerging pathogens in cases of enteric disease with a wide array of gastrointestinal symptoms.

2.
Artículo en Inglés | MEDLINE | ID: mdl-29914964

RESUMEN

We tested the in vitro susceptibility of ceftazidime-avibactam and ceftolozane-tazobactam and 13 other antibiotics against 91 Burkholderia cepacia complex (BCC) strains isolated from cystic fibrosis patients since 2012. The highest susceptibility (82%) was found for trimethoprim-sulfamethoxazole. Eighty-one and 63% of all BCC strains were susceptible to ceftazidime-avibactam and ceftolozane-tazobactam, respectively. For temocillin, ceftazidime, piperacillin-tazobactam, and meropenem, at least 50% of the strains were susceptible. B. stabilis seems to be more resistant than other BCC species.


Asunto(s)
Compuestos de Azabiciclo/farmacología , Complejo Burkholderia cepacia/efectos de los fármacos , Ceftazidima/farmacología , Cefalosporinas/farmacología , Fibrosis Quística/microbiología , Tazobactam/farmacocinética , Antibacterianos/farmacología , Complejo Burkholderia cepacia/aislamiento & purificación , Combinación de Medicamentos , Humanos , Pruebas de Sensibilidad Microbiana , Sulfametoxazol/farmacología , Tazobactam/farmacología , Trimetoprim/farmacología
3.
Appl Environ Microbiol ; 84(7)2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29352086

RESUMEN

Few data have been published on the occurrence and functional role of acetic acid bacteria (AAB) in lambic beer production processes, mainly due to their difficult recovery and possibly unknown role. Therefore, a novel aseptic sampling method, spanning both the spatial and temporal distributions of the AAB and their substrates and metabolites, was combined with a highly selective medium and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as a high-throughput dereplication method followed by comparative gene sequencing for their isolation and identification, respectively. The AAB (Acetobacter species more than Gluconobacter species) proliferated during two phases of the lambic beer production process, represented by Acetobacter orientalis during a few days in the beginning of the fermentation and Acetobacter pasteurianus from 7 weeks until 24 months of maturation. Competitive exclusion tests combined with comparative genomic analysis of all genomes of strains of both species available disclosed possible reasons for this successive dominance. The spatial analysis revealed that significantly higher concentrations of acetic acid (from ethanol) and acetoin (from lactic acid) were produced at the tops of the casks, due to higher AAB counts and a higher metabolic activity of the AAB species at the air/liquid interface during the first 6 months of lambic beer production. In contrast, no differences in AAB species diversity occurred throughout the casks.IMPORTANCE Lambic beer is an acidic beer that is the result of a spontaneous fermentation and maturation process. Acidic beers are currently attracting attention worldwide. Part of the acidity of these beers is caused by acetic acid bacteria (AAB). However, due to their difficult recovery, they were never investigated extensively regarding their occurrence, species diversity, and functional role in lambic beer production. In the present study, a framework was developed for their isolation and identification using a novel aseptic sampling method in combination with matrix-assisted laser desorption ionization-time of flight mass spectrometry as a high-throughput dereplication technique followed by accurate molecular identification. The sampling method applied enabled us to take spatial differences into account regarding both enumerations and metabolite production. In this way, it was shown that more AAB were present and more acetic acid was produced at the air/liquid interface during a major part of the lambic beer production process. Also, two different AAB species were encountered, namely, Acetobacter orientalis at the beginning and Acetobacter pasteurianus in a later stage of the production process. This developed framework could also be applied for other fermentation processes.


Asunto(s)
Ácido Acético/metabolismo , Acetobacter/metabolismo , Cerveza/microbiología , Gluconobacter/metabolismo , Fermentación , Microbiota
4.
Eur J Clin Microbiol Infect Dis ; 36(11): 2263-2271, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28840370

RESUMEN

Burkholderia sp. infections are extremely complex in cystic fibrosis (CF) patients, especially considering the lack of knowledge regarding its behavior, its relationship with prognosis, as well as its transmissibility and multidrug resistance features. This study evaluated the frequency of chronic infection by Burkholderia, using microbiological and clinical data. Ninety-eight patients with CF attended from July 2011 to April 2014 in a Brazilian reference hospital were included. Antimicrobial activity, molecular epidemiology, Shwachman score, body mass index, exacerbations, and lung function were analyzed. Nine patients had chronic colonization, and all of them showed preserved pulmonary function levels, body mass index, and Shwachman score. Meropenem was the most effective antibiotic; however, divergent results were shown by other studies. Cross-contamination may have occurred in only two unrelated patients of different ages, who were colonized by B. vietnamiensis, which does not occur frequently. Twelve new sequence types (STs) were identified and three STs have presented intercontinental distribution. None of the patients presented known epidemic strains. In conclusion, a relatively low number of patients with chronic colonization and suspected cross-infection were identified. Different from other studies that have found CF patients chronically colonized with Burkholderia sp. having a greater deterioration of lung function, more frequent antibiotic therapy, and increased mortality, in the current study, the patients showed good clinical outcomes and favorable options for antibiotics therapy. This study also updated the epidemiological database, which facilitates the multicentric collaborative analysis and assists in the control of global infection by these pathogens.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones por Burkholderia/tratamiento farmacológico , Infecciones por Burkholderia/epidemiología , Complejo Burkholderia cepacia/aislamiento & purificación , Fibrosis Quística/microbiología , Adolescente , Adulto , Brasil/epidemiología , Infecciones por Burkholderia/complicaciones , Infecciones por Burkholderia/patología , Complejo Burkholderia cepacia/clasificación , Complejo Burkholderia cepacia/genética , Ceftazidima/uso terapéutico , Niño , Preescolar , Infección Hospitalaria , Fibrosis Quística/complicaciones , Electroforesis en Gel de Campo Pulsado , Femenino , Hospitales , Humanos , Lactante , Pulmón/patología , Masculino , Meropenem , Pruebas de Sensibilidad Microbiana , Tipificación Molecular , Pruebas de Función Respiratoria , Tienamicinas/uso terapéutico , Resultado del Tratamiento , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Adulto Joven
5.
Syst Appl Microbiol ; 40(1): 42-50, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27816261

RESUMEN

Nine strains of a novel Fusobacterium sp. were isolated from the stomach of 6-8 months old and adult pigs. The isolates were obligately anaerobic, although they endured 2h exposure to air. Phylogenetic analysis based on 16S rRNA and gyrase B genes demonstrated that the isolates showed high sequence similarity with Fusobacterium mortiferum, Fusobacterium ulcerans, Fusobacterium varium, Fusobacterium russii and Fusobacterium necrogenes, but formed a distinct lineage in the genus Fusobacterium. Comparative analysis of the genome of the type strain of this novel Fusobacterium sp. confirmed that it is different from other recognized Fusobacterium spp. DNA-DNA hybridization, fingerprinting and genomic %GC determination further supported the conclusion that the isolates belong to a new, distinct species. The isolates were also distinguishable from these and other Fusobacterium spp. by phenotypical characterization. The strains produced indole and exhibited proline arylamidase and glutamic acid decarboxylase activity. They did not hydrolyse esculin, did not exhibit pyroglutamic acid arylamidase, valine arylamidase, α-galactosidase, ß-galactosidase, ß-galactosidase-6-phosphate or α-glucosidase activity nor produced acid from cellobiose, glucose, lactose, mannitol, mannose, maltose, raffinose, saccharose, salicin or trehalose. The major fatty acids were C16:0 and C18:1ω9c. The name Fusobacterium gastrosuis sp. nov. is proposed for the novel isolates with the type strain CDW1(T) (=DSM 101753(T)=LMG 29236(T)). We also demonstrated that Clostridium rectum and mortiferum Fusobacterium represent the same species, with nomenclatural priority for the latter.


Asunto(s)
Infecciones por Fusobacterium/veterinaria , Fusobacterium/clasificación , Fusobacterium/aislamiento & purificación , Estómago/microbiología , Anaerobiosis , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis por Conglomerados , Citosol/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Fusobacterium/genética , Infecciones por Fusobacterium/microbiología , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Porcinos
6.
Int J Tuberc Lung Dis ; 20(9): 1257-62, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27510255

RESUMEN

SETTING: Over 150 potentially pathogenic non-tuberculous mycobacteria (NTM) species have been described, posing an onerous challenge for clinical laboratory diagnosis. OBJECTIVE: To evaluate different approaches for the identification of 40 clinically relevant NTM isolates whose species were not reliably identified using our routine diagnostic workflow comprising phenotypic tests and hsp65 polymerase chain reaction restriction analysis. DESIGN: We used 1) sequencing analysis of four conserved gene targets: 16S rRNA, rpoB, hsp65 and sodA; 2) two commercial reverse hybridisation assays; and 3) protein analysis using matrix-assisted laser desorption/ionisation time of flight mass spectrometry (MALDI-TOF MS). RESULTS: Combined, but not individual, sequence analysis allowed reliable species identification for 30/40 (75%) isolates, including species previously unknown to be circulating in Argentina. Commercial kits outperformed our routine identification in only 5/35 isolates, and misclassified many more. MALDI-TOF MS accurately identified species in 22/36 (61%) isolates and did not misidentify any. CONCLUSIONS: Commercial kits did not resolve the problem of species of NTM isolates that elude identification. Combined DNA sequence analysis was the approach of choice. MALDI-TOF MS shows promise as a powerful, rapid and accessible tool for the rapid identification of clinically relevant NTM in the diagnostic laboratory, and its accuracy can be maximised by building up a customised NTM spectrum database.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Micobacterias no Tuberculosas/genética , Micobacterias no Tuberculosas/aislamiento & purificación , Argentina , Proteínas Bacterianas/genética , Técnicas Bacteriológicas , Chaperonina 60/genética , ADN Bacteriano/genética , Genes Bacterianos , Humanos , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Superóxido Dismutasa/genética
7.
Infect Immun ; 84(8): 2307-2316, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27245408

RESUMEN

A urease-negative, fusiform, novel bacterium named Helicobacter saguini was isolated from the intestines and feces of cotton-top tamarins (CTTs) with chronic colitis. Helicobacter sp. was detected in 69% of feces or intestinal samples from 116 CTTs. The draft genome sequence, obtained by Illumina MiSeq sequencing, for H. saguini isolate MIT 97-6194-5, consisting of ∼2.9 Mb with a G+C content of 35% and 2,704 genes, was annotated using the NCBI Prokaryotic Genomes Automatic Annotation Pipeline. H. saguini contains homologous genes of known virulence factors found in other enterohepatic helicobacter species (EHS) and H. pylori These include flagellin, γ-glutamyl transpeptidase (ggt), collagenase, the secreted serine protease htrA, and components of a type VI secretion system, but the genome does not harbor genes for cytolethal distending toxin (cdt). H. saguini MIT 97-6194-5 induced significant levels of interleukin-8 (IL-8) in HT-29 cell culture supernatants by 4 h, which increased through 24 h. mRNAs for the proinflammatory cytokines IL-1ß, tumor necrosis factor alpha (TNF-α), IL-10, and IL-6 and the chemokine CXCL1 were upregulated in cocultured HT-29 cells at 4 h compared to levels in control cells. At 3 months postinfection, all H. saguini-monoassociated gnotobiotic C57BL/129 IL-10(-/-) mice were colonized and had seroconverted to H. saguini antigen with a significant Th1-associated increase in IgG2c (P < 0.0001). H. saguini induced a significant typhlocolitis, associated epithelial defects, mucosa-associated lymphoid tissue (MALT) hyperplasia, and dysplasia. Inflammatory cytokines IL-22, IL-17a, IL-1ß, gamma interferon (IFN-γ), and TNF-α, as well as inducible nitric oxide synthase (iNOS) were significantly upregulated in the cecal tissues of infected mice. The expression of the DNA damage response molecule γ-H2AX was significantly higher in the ceca of H. saguini-infected gnotobiotic mice than in the controls. This model using a nonhuman primate Helicobacter sp. can be used to study the pathogenic potential of EHS isolated from primates with naturally occurring inflammatory bowel disease (IBD) and colon cancer.


Asunto(s)
Colitis Ulcerosa/veterinaria , Colitis/microbiología , Colitis/patología , Helicobacter/fisiología , Enfermedades de los Monos/microbiología , Animales , Anticuerpos Antibacterianos/inmunología , Línea Celular , Colitis/genética , Colitis/inmunología , Citocinas/genética , Modelos Animales de Enfermedad , Heces/microbiología , Expresión Génica , Genoma Bacteriano , Helicobacter/clasificación , Helicobacter/aislamiento & purificación , Histonas/metabolismo , Humanos , Mediadores de Inflamación/metabolismo , Interleucina-10/deficiencia , Ratones , Ratones Noqueados , Filogenia , ARN Ribosómico 16S/genética
8.
Benef Microbes ; 7(4): 585-95, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27291404

RESUMEN

The isolation of potentially probiotic strains and the subsequent study of their properties are very important steps to gain insight in the health benefits ascribed to sugary and milk kefir. The aim of the present study was to characterise fifteen Lactobacillus strains isolated from these beverages by determining some surface properties and their ability to antagonise enterocyte cell damage after Salmonella infection in vitro. Lactobacillus surface properties were determined by hydrophobicity, autoaggregation, and coaggregation assays with Salmonella. In addition, lactobacilli adhesion to Caco-2/TC-7 cells and the effect on Salmonella invasion were evaluated. Finally, the disassembly of F-actin cytoskeleton on intestinal epithelial cells was assayed in vitro when Salmonella infection was performed in the presence of selected Lactobacillus strains. Ten out of the 15 strains showed a high adhesion capacity to Caco-2/TC-7 cells. Most of the strains were hydrophilic and non-autoaggregating. Strains isolated from sugary kefir were non-coaggregating with Salmonella, while strains Lactobacillus paracasei CIDCA 83120, 83121, 83123, 83124, 8339, 83102 isolated from milk kefir were able to coaggregate after 1 h. L. paracasei CIDCA 8339 and Lactobacillus kefiri CIDCA 83102 were able to diminish Salmonella invasion to the enterocytes. An antagonistic effect on cytoskeleton disruption elicited by the pathogen was also demonstrated. Our results suggest that both strains isolated from milk kefir could be considered as appropriate probiotic candidates.


Asunto(s)
Enterocitos/microbiología , Kéfir/microbiología , Lactobacillus , Leche/microbiología , Probióticos/uso terapéutico , Infecciones por Salmonella/terapia , Animales , Adhesión Bacteriana , Células CACO-2 , Línea Celular , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Lactobacillus/aislamiento & purificación , Lactobacillus/fisiología
9.
Eur J Clin Microbiol Infect Dis ; 34(7): 1403-13, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25820290

RESUMEN

Drug susceptibility testing (DST) of rapidly growing mycobacteria (RGM) are recommended for guiding the antimicrobial therapy. We have evaluated the use of resazurin in Mueller-Hinton medium (MHR) for MIC determination of RGM and compared the results with those obtained with the reference standard broth microdilution in Mueller-Hinton (MH) and with the resazurin microtiter assay (REMA) in 7H9 broth. The MIC of eight drugs: amikacin (AMI), cefoxitin (FOX), ciprofloxacin (CIP), clarithromycin (CLA), doxycycline (DOX), linezolid (LZD), moxifloxacin (MXF) and trimethoprim-sulfamethoxazole (TMP-SMX) were evaluated against 76 RGM (18 species) using three methods (MH, MHR, and REMA) in a 96-well plate format incubated at 37 °C over 3-5 days. Results obtained in the MH plates were interpreted by the appearance of turbidity at the bottom of the well before adding the resazurin. MHR and 7H9-REMA plates were read by visual observation for a change in color from blue to pink. The majority of results were obtained at day 5 for MH and 1 day after for MHR and 7H9-REMA. However, the preliminary experiment on time to positivity results using the reference strain showed that the resazurin can be added to the MH at day 2 to produce the results at day 3, but future studies with large sets of strains are required to confirm this suggestion. A high level of agreement (kappa 1.000-0.884) was obtained between the MH and the MHR. Comparison of results obtained with 7H9-REMA, on the other hand, revealed several discrepancies and a lower level of agreement (kappa 1.000-0.111). The majority of the strains were resistant to DOX and TMP-SMX, and the most active antimicrobials for RGM were AMI and FOX. In the present study, MHR represented an excellent alternative for MIC determination of RGM. The results could be read reliably, more easily, and more quickly than with the classical MH method.


Asunto(s)
Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Mycobacterium/efectos de los fármacos , Humanos , Mycobacterium/crecimiento & desarrollo , Mycobacterium/aislamiento & purificación , Infecciones por Mycobacterium/microbiología , Micobacterias no Tuberculosas/efectos de los fármacos , Micobacterias no Tuberculosas/crecimiento & desarrollo , Micobacterias no Tuberculosas/aislamiento & purificación , Factores de Tiempo
10.
Clin Microbiol Infect ; 19(9): 832-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23173820

RESUMEN

The Burkholderia cepacia complex is a group of Gram-negative bacteria known as respiratory pathogens in cystic fibrosis patients, but also increasingly reported as a cause of healthcare associated infections. We describe an outbreak of B. cepacia bloodstream infections in a referral hospital in Phnom Penh, Cambodia. Over a 1.5-month period, blood cultures from eight adult patients grew B. cepacia. Bloodstream infection occurred after a median of 2.5 days of hospitalisation. Three patients died: 7, 10 and 17 days after blood cultures were sampled. As part of the outbreak investigation, patient files were reviewed and environmental sampling was performed. All patients had peripheral venous catheters that were flushed with Ringer lactate drawn from a 1 L bag, used as multiple-dose vial at the ward. Cultures of unopened Ringer lactate and disinfectants remained sterile but an in-use bag of Ringer lactate solution and the dispensing pin grew B. cepacia. The isolates from patients and flushing solution were identified as B. cepacia by recA gene sequence analysis, and random amplified polymorphic DNA typing confirmed clonal relatedness. The onset of the outbreak had coincided with the introduction of a dispensing pin with a screw fit that did not allow proper disinfection. Re-enforcement of aseptic procedures with sterile syringe and needle has ended the outbreak. Growth of B. cepacia should alert the possibility of healthcare associated infection also in tropical resource-limited settings. The use of multiple-dose vials should be avoided and newly introduced procedures should be assessed for infection control risks.


Asunto(s)
Bacteriemia/epidemiología , Infecciones por Burkholderia/epidemiología , Burkholderia cepacia/aislamiento & purificación , Infecciones Relacionadas con Catéteres/epidemiología , Infección Hospitalaria/epidemiología , Contaminación de Medicamentos , Soluciones Isotónicas , Adulto , Anciano , Bacteriemia/microbiología , Técnicas de Tipificación Bacteriana , Infecciones por Burkholderia/microbiología , Infecciones por Burkholderia/prevención & control , Burkholderia cepacia/genética , Cambodia/epidemiología , Infecciones Relacionadas con Catéteres/microbiología , Infección Hospitalaria/prevención & control , Brotes de Enfermedades , Femenino , Humanos , Control de Infecciones/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Técnica del ADN Polimorfo Amplificado Aleatorio , Lactato de Ringer , Dispositivos de Acceso Vascular
11.
Lett Appl Microbiol ; 55(4): 265-73, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22774847

RESUMEN

AIMS: To evaluate the potential use of MALDI-TOF MS for fast and reliable classification and identification of lactic acid bacteria (LAB) from traditional fermented foods. METHODS AND RESULTS: A total of 119 strains of LAB from fermented meat (nem chua) were analysed with both (GTG)(5)-PCR fingerprinting and MALDI-TOF MS. Cluster analysis of the profiles revealed five species represented by a single isolate both in (GTG)(5)-PCR and in MALDI-TOF MS; five species grouped alike for (GTG)(5)-PCR and for MALDI-TOF MS; however, differences in minimal similarity between the delineated (GTG)(5)-PCR and MALDI-TOF MS clusters could be observed; three species showed more heterogeneity in their MALDI-TOF MS profiles compared to their (GTG)(5)-PCR profiles; two species, each represented by a single MALDI-TOF cluster, were subdivided in the corresponding (GTG)(5)-PCR dendrogram. As proof of the identification potential of MALDI-TOF MS, LAB diversity from one fermented mustard sample was analysed using MALDI-TOF MS. PheS gene sequencing was used for validation. CONCLUSIONS: MALDI-TOF MS is a powerful, fast, reliable and cost-effective technique for the identification of LAB associated with the production of fermented foods. SIGNIFICANCE AND IMPACT OF THE STUDY: Food LAB can be identified using MALDI-TOF MS, and its application could possibly be extended to other food matrices and/or other food-derived micro-organisms.


Asunto(s)
Fermentación , Microbiología de Alimentos/métodos , Lactobacillaceae/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Análisis por Conglomerados , Ácido Láctico , Lactobacillaceae/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Vietnam
12.
Int J Syst Evol Microbiol ; 62(Pt 2): 299-306, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21421932

RESUMEN

Three gram-negative, microaerophilic bacteria, strains ASB1(T), ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1(T), ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter bizzozeronii, 'Candidatus Helicobacter heilmannii', Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1(T), ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1(T), ASB2 and ASB3 showed approximately 91 % similarity to those of 'Candidatus Helicobacter heilmannii'. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1(T), ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to 'Candidatus Helicobacter heilmannii', which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1(T) (=DSM 24751 (T) =LMG 26292(T)) [corrected].


Asunto(s)
Enfermedades de los Gatos/microbiología , Mucosa Gástrica/microbiología , Infecciones por Helicobacter/veterinaria , Helicobacter heilmannii/clasificación , Helicobacter heilmannii/aislamiento & purificación , Animales , Proteínas Bacterianas/química , Técnicas de Tipificación Bacteriana , Gatos , Chaperonina 60/genética , Chaperonina 60/metabolismo , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Perros , Electroforesis/métodos , Genes de ARNr , Infecciones por Helicobacter/microbiología , Helicobacter heilmannii/genética , Helicobacter heilmannii/metabolismo , Humanos , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie , Ureasa/genética
13.
Folia Microbiol (Praha) ; 56(1): 80-3, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21390569

RESUMEN

A group of lactobacilli isolated from the cervix of 31 healthy women was characterized by (GTG)(5)-polymerase chain reaction (PCR) fingerprinting in order to evaluate this method for identification of vaginal lactobacilli. Obtained fingerprints were compared with profiles available in an in-house database of the CCM bacteria collection covering type and reference strains of multiple lactic acid bacteria including lactobacilli. Selected strains representing individual clusters were further identified by pheS gene sequencing. In total, six lactobacillus species were found among lactobacilli isolated from the cervix of healthy women. The (GTG)(5)-PCR method identified Lactobacillus gasseri (11 strains), Lactobacillus fermentum (one), and some of the Lactobacillus jensenii strains (eight out of 11), but failed to identify the remaining strains, including the Lactobacillus crispatus (18), Lactobacillus mucosae (one), and Lactobacillus vaginalis (one) species. L. jensenii strains were distributed over two fingerprint clusters. The majority of samples was dominated by one (GTG)(5)-PCR type. The rep-PCR fingerprinting using the (GTG)(5) primer allowed straightforward identification of many, but not all, isolates. This method has been shown to be a useful tool for fast screening and grouping of vaginal lactobacilli, but its combination with another identification method is needed to obtain reliable identification results. In addition, Lactobacillus acidophilus was not shown to be the most common inhabitant of the female genital tract as generally assumed.


Asunto(s)
Cuello del Útero/microbiología , Dermatoglifia del ADN/métodos , Cartilla de ADN/genética , Lactobacillus/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Adolescente , Adulto , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Femenino , Humanos , Lactobacillus/clasificación , Lactobacillus/genética , Filogenia , Adulto Joven
14.
Clin Microbiol Infect ; 17(7): 1001-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20673261

RESUMEN

Biochemical identification of Campylobacter and related organisms is not always specific, and may lead to diagnostic errors. The API Campy, the Vitek 2 system and matrix-assisted desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) are commercially available methods that are routinely used for the identification of these microorganisms. In the present study, we used 224 clinical isolates and ten reference strains previously identified by multiple PCR assays, whole cell protein profiling and either DNA-DNA hybridization or sequencing analysis to compare the reliability of these three methods for the identification of Campylobacter and related pathogens. The API Campy accurately identified 94.4% of Campylobacter jejuni ssp. jejuni and 73.8% of Campylobacter coli, but failed to correctly identify 52.3% of other Epsilobacteria. The Vitek 2 Neisseria-Haemophilus card correctly identified most C. jejuni ssp.jejuni (89.6%) and C. coli (87.7%) strains, which account for the majority of campylobacterioses reported in humans, but it failed in the identification of all of the other species. Despite a good identification rate for both C. jejuni ssp. jejuni and C. coli, both methods showed poor sensitivity in the identification of related organisms, and additional tests were frequently needed. In contrast to API Campy and Vitek, MALDI-TOF MS correctly identified 100% of C. coli and C. jejuni strains tested. With an overall sensitivity of 98.3% and a short response time, this technology appears to be a reliable and promising method for the routine identification of Campylobacter and other Epsilobacteria.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Epsilonproteobacteria/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/diagnóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Humanos , Sensibilidad y Especificidad
16.
Int J Syst Evol Microbiol ; 60(Pt 9): 2016-2022, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19801389

RESUMEN

The protein profiles, genomic amplified fragment length polymorphism patterns and 16S rRNA and cpn60 gene sequences of a diverse collection of 26 Bacteroides ureolyticus strains, along with published data on their DNA base, respiratory quinone and cellular fatty acid compositions, were used to reassess the taxonomy of this bacterial species. The results demonstrate that this organism is most appropriately allocated in the genus Campylobacter. The presence of much higher amounts of 18 : 1omega7c in its cellular fatty acid profile and its ability to digest gelatin and casein are the characteristics that differentiate it from present species of the genus Campylobacter. Therefore we propose to reclassify this species incertae sedis into the genus Campylobacter as Campylobacter ureolyticus with strain LMG 6451(T) (=CCUG 7319(T) =NCTC 10941(T)) as the type strain.


Asunto(s)
Bacteroides/clasificación , Campylobacter/clasificación , Bacteroides/genética , Bacteroides/aislamiento & purificación , Bacteroides/metabolismo , Campylobacter/genética , Campylobacter/aislamiento & purificación , Campylobacter/metabolismo , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética
17.
Indian J Med Microbiol ; 27(2): 128-33, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19384035

RESUMEN

BACKGROUND: The Burkholderia cepacia complex (BCC) and Stenotrophomonas maltophilia are closely related groups of non-fermenting gram-negative bacilli (NFGNBs) having a similar spectrum of infections ranging from superficial to deep-seated and disseminated infections. Identification of these lysine decarboxylase-positive NFGNBs lags behind in most Indian laboratories. A simplified identification scheme was devised for these two pathogens that allowed us to isolate them with an increasing frequency at our tertiary care institute. MATERIALS AND METHODS: A simple five-tube conventional biochemical identification of these bacteria has been standardized. In the beginning, some of the isolates were confirmed from the International B. cepacia Working group, Belgium. Molecular identification and typing using recA polymerase chain reaction-restriction fragment length polymorphism was also standardized for BCC. For short-term preservation of BCC, an innovative method of preserving the bacteria in Robertson's cooked medium tubes kept in a domestic refrigerator was developed. RESULTS: Thirty-nine isolates of BCC isolates were obtained from various specimens (30 from blood cultures) and 22 S. maltophilia (13 blood cultures and 9 respiratory isolates) were isolated during the year 2007 alone. CONCLUSIONS: BCC and S. maltophilia can be identified with relative ease using a small battery of biochemical reactions. Use of simplified methods will allow greater recognition of their pathogenic potential and correct antimicrobials should be advised in other clinical laboratories and hospitals.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Complejo Burkholderia cepacia/aislamiento & purificación , Carboxiliasas/metabolismo , Infecciones por Bacterias Gramnegativas/diagnóstico , Stenotrophomonas maltophilia/aislamiento & purificación , Técnicas de Tipificación Bacteriana/normas , Complejo Burkholderia cepacia/metabolismo , Dermatoglifia del ADN/métodos , Dermatoglifia del ADN/normas , ADN Bacteriano/genética , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , India , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Polimorfismo de Longitud del Fragmento de Restricción , Preservación Biológica/métodos , Rec A Recombinasas/genética , Stenotrophomonas maltophilia/metabolismo
18.
J Appl Microbiol ; 106(4): 1081-92, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19187144

RESUMEN

AIMS: To investigate the circulation of predominant sourdough lactic acid bacteria (LAB) species in the production environment of two Belgian artisan sourdough bakeries. METHODS AND RESULTS: Isolates were collected from sourdoughs, flour, hands of the baker and air in the bakery setting and taxonomically characterized using repetitive element sequence-based PCR fingerprinting, pheS and/or 16S rRNA gene sequencing and amplified fragment length polymorphism (AFLP) analysis. In parallel, PCR-DGGE (denaturing gradient gel electrophoresis) analysis of V3-16S rDNA amplicons was applied to visualize the predominant bacterial population in the sourdoughs and the corresponding bakery environment (flour, hands of the baker, air and bakery equipment). Both approaches revealed that sourdoughs produced at D01 and D10 were mainly dominated by Lactobacillus spicheri and L. plantarum and by L. sanfranciscensis, respectively, and that these LAB species also circulated in the corresponding bakery environment. Furthermore, AFLP fingerprinting demonstrated that sourdough and bakery environment isolates of these species were genetically indistinguishable. For more sensitive source-tracking, SYBR Green-based real-time PCR assays were developed using species-specific primers targeting the pheS gene of L. plantarum and L. sanfranciscensis, detected in air samples from D01 and D10, respectively. CONCLUSIONS: The results obtained in this study indicate that specific strains of LAB persist in artisan doughs over years and circulate in the bakery environment. Furthermore, the importance of air as a potential carrier of LAB in artisan bakery environments was demonstrated. SIGNIFICANCE AND IMPACT OF THE STUDY: PheS-based real-time PCR can be used to detect, quantify and/or monitor specific LAB species (e.g. starter cultures) in sourdough and bakery environment samples.


Asunto(s)
Pan/microbiología , Fermentación , Industria de Alimentos , Lactobacillus/clasificación , Aire/análisis , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Bélgica , Dermatoglifia del ADN/métodos , ADN Bacteriano/genética , Electroforesis en Gel de Poliacrilamida/métodos , Harina/microbiología , Variación Genética , Mano/microbiología , Humanos , Lactobacillus/genética , Lactobacillus/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
19.
Nepal Med Coll J ; 11(4): 222-4, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20635597

RESUMEN

Burkholderia cepacia complex (BCC) is being increasingly recognized as an important pathogen of humans. During the year 2007-8, 39 putative BCC isolates were obtained from 21 cases and subjected to recA PCR RFLP. Twenty-four isolates were confirmed as Burkholderia cenocepacia IIIA (nineteen isolates, recA PCR RFLP type G and five isolates, recA PCR RFLP type I), six were confirmed as B. cepacia (recA PCR RFLP type E). BCC were isolated from inpatients of different wards of Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh with increased isolation from children admitted to different wards of Advanced Pediatric Centre (11/21 cases). BCC isolates are often resistant to most commonly used antibiotics and an early use of effective antimicrobial therapy can decrease morbidity and mortality.


Asunto(s)
Complejo Burkholderia cepacia/aislamiento & purificación , Sepsis/microbiología , Antibacterianos/uso terapéutico , Infecciones por Burkholderia , Complejo Burkholderia cepacia/genética , ADN Bacteriano/genética , Farmacorresistencia Bacteriana , Femenino , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
20.
J Appl Microbiol ; 106(2): 486-95, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19054226

RESUMEN

AIMS: To identify lactic acid bacteria (LAB) present in Moroccan dairy products to establish and preserve their microbial species diversity. METHODS AND RESULTS: Thirty-seven samples were collected from different farms. A total of 146 LAB were isolated and subjected to (GTG)(5)-PCR analysis. Comparison of the profiles with data available at the Moroccan Coordinated Collections of Micro-organisms allowed identification of 85 isolates. The remaining 61 were subjected to SDS-PAGE analysis of whole cell proteins. Comparison of the profiles with data available at the Belgian Coordinated Collections of Micro-organisms allowed identification of 43 isolates. Several of the remaining 18 isolates exhibited identical protein electrophoretic fingerprints. Therefore, eight representatives of them were subjected to partial pheS gene sequencing which allowed identification of all remaining isolates. In raw milk, six genera were found while in 'lben', three were found. This is the first report of Leuconostoc kimchii in dairy products. CONCLUSIONS: LAB diversity was established using a stepwise polyphasic identification approach. It used the expertise of both research bodies involved in this study and proved to be cost-effective for the identification of all isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: To establish LAB diversity in Moroccan dairy products which could be a source of strains with specific properties.


Asunto(s)
Microbiología de Alimentos , Lactobacillaceae/aislamiento & purificación , Leche/microbiología , Animales , Técnicas de Tipificación Bacteriana , Productos Lácteos Cultivados/microbiología , Dermatoglifia del ADN , ADN Bacteriano/genética , Electroforesis en Gel de Poliacrilamida , Lactobacillaceae/clasificación , Lactobacillaceae/genética , Leuconostoc/clasificación , Leuconostoc/genética , Leuconostoc/aislamiento & purificación , Marruecos
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