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1.
Ann Oncol ; 29(9): 1911-1917, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30060061

RESUMEN

Background: Deregulated Notch signaling due to mutation or overexpression of ligands and/or receptors is implicated in various human malignancies. γ-Secretase inhibitors inhibit Notch signaling by preventing cleavage of transmembrane domain of Notch protein. LY3039478 is a novel, potent Notch inhibitor decreases Notch signaling and its downstream biologic effects. In this first-in-human study, we report the safety, pharmacokinetic (PK) profile, pharmacodynamic effects, and antitumor activity of LY3039478 in patients with advanced or metastatic cancer. Methods: This phase I, open-label, multicenter, nonrandomized, and dose-escalation phase study determined and confirmed the recommended phase II dose of LY3039478 (oral dose: 2.5-100 mg, thrice weekly (TIW) on a 28-day cycle). The primary objectives are to determine (part A) and confirm (part B) a recommended phase II dose that may be safely administered to patients with advanced or metastatic cancer, and secondary objectives include evaluation of safety, tolerability, PK parameters, and preliminary antitumor activity of LY3039478. Results: A total of 110 patients were treated with LY3039478 monotherapy between 31 October 2012 and 15 July 2016. Dose-limiting toxicities were thrombocytopenia, colitis, and nausea. Most adverse events were gastrointestinal. The recommended phase II dose was 50 mg TIW, because of its better tolerability compared with 75 mg. The PKs of LY3039478 appeared dose proportional. Pharmacodynamic data indicate an ∼80% inhibition of plasma Aß, and >50% inhibition of Notch-regulated genes hairy and enhancer of split-1, cyclin D1, and Notch-regulated ankyrin repeat at 45-100-mg dose. Clinical activity (tumor necrosis, metabolic response, or tumor shrinkage) was observed in patients with breast cancer, leiomyosarcoma, and adenoid cystic carcinoma. Conclusion: Potent inhibition of Notch signaling by LY3039478 was well tolerated at doses associated with target engagement, and demonstrated evidence of clinical activity in heavily pretreated patients. Further investigation with LY3039478 as monotherapy and in combination with targeted agent or chemotherapy is ongoing. Clinicaltrials.gov ID: NCT01695005.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Antineoplásicos/administración & dosificación , Benzazepinas/administración & dosificación , Neoplasias/tratamiento farmacológico , Receptores Notch/antagonistas & inhibidores , Administración Oral , Adolescente , Adulto , Anciano , Secretasas de la Proteína Precursora del Amiloide/sangre , Antineoplásicos/efectos adversos , Benzazepinas/efectos adversos , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/sangre , Neoplasias/genética , Receptores Notch/genética , Receptores Notch/metabolismo , Criterios de Evaluación de Respuesta en Tumores Sólidos , Adulto Joven
2.
Can J Microbiol ; 63(7): 644-647, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28460189

RESUMEN

Neisseria meningitidis serogroups B and C have been responsible for the majority of invasive meningococcal disease in Australia, with serogroup B strains causing an increasing proportion of cases in recent years. Serogroup Y has typically caused sporadic disease in Australia. In 2002, a cluster of 4 cases was reported from a rural region in Queensland. Three of these cases were serogroup C, with 1 case diagnosed by molecular detection only, and the fourth case was identified as a serogroup Y infection. Genomic analysis, including antigen finetyping, multilocus sequence typing (MLST), and core genome MLST, demonstrated that the serogroup Y case, though spatially and temporally linked to a serogroup C disease cluster, was not the product of a capsule switch and that one of the serogroup C isolates had a deletion of the entire porA sequence.


Asunto(s)
Brotes de Enfermedades , Infecciones Meningocócicas/microbiología , Neisseria meningitidis/genética , Porinas/genética , Análisis por Conglomerados , Humanos , Infecciones Meningocócicas/epidemiología , Tipificación de Secuencias Multilocus , Neisseria meningitidis/inmunología , Neisseria meningitidis/aislamiento & purificación , Queensland , Análisis de Secuencia de ADN , Serogrupo
3.
Braz J Microbiol ; 41(3): 707-17, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24031547

RESUMEN

We studied the peptide-degrading anaerobic communities of methanogenic reactors from two mesophilic full-scale modified upflow anaerobic sludge blanket (UASB) reactors treating brewery wastewater in Colombia. Most probable number (MPN) counts varied between 7.1 x 10(8) and 6.6 × 10(9) bacteria/g volatile suspended solids VSS (Methanogenic Reactor 1) and 7.2 × 10(6) and 6.4 × 10(7) bacteria/g (VSS) (Methanogenic Reactor 2). Metabolites detected in the highest positive MPN dilutions in both reactors were mostly acetate, propionate, isovalerate and, in some cases, negligible concentrations of butyrate. Using the highest positive dilutions of MPN counts, 50 dominant strains were isolated from both reactors, and 12 strains were selected for sequencing their 16S rRNA gene based on their phenotypic characteristics. The small-subunit rRNA gene sequences indicated that these strains were affiliated to the families Propionibacteriaceae, Clostridiaceae and Syntrophomonadaceae in the low G + C gram-positive group and Desulfovibrio spp. in the class δ-Proteobacteria. The main metabolites detected in the highest positive dilutions of MPN and the presence of Syntrophomonadaceae indicate the effect of the syntrophic associations on the bioconversion of these substrates in methanogenic reactors. Additionally, the potential utilization of external electron acceptors for the complete degradation of amino acids by Clostridium strains confirms the relevance of these acceptors in the transformation of peptides and amino acids in these systems.

4.
Data Brief ; 19: 82-85, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29892620

RESUMEN

In recent past, the respiratory infection has emerged as a great challenge to the poultry farmers. Various pathogens including Avian pneumovirus (APV), Avian influenza virus (AIV), Infectious bronchitis virus (IBV) and Newcastle disease virus (NDV), Avibacterium paragallinarum, Ornithobacterium rhinotracheale (ORT), Mycoplasma synoviae (MS), Mycoplasma gallisepticum (MG) and Avian pathogenic Escherichia coli (APEC) are involved in the respiratory disease complex in birds [1], [2] (Bradbury, 1984; Roussan et al., 2008). Hence, respiratory disease complex is the most serious disease affecting to poultry and causes heavy economic losses in the poultry industry worldwide [3] (Murthy et al., 2008). In recent years, metagenomics is powerful analyzing tool for detection of pathogens directly from clinical samples without any prior knowledge of the organism in a given sample [4], [5] (Schuster, 2008; Pereira et al., 2010). High throughput Next-Generation-Sequencing technology was used for sequencing the isolated genomic DNA. These data provides an insight about taxonomic and functional status of microorganisms responsible for causing respiratory infection in broiler. The data of these metagenome are available in the BioSample Submission Portal as Bioproject PRJNA339659 and SRA accession number SRR5997823, SRR5992854, SRR6037376, SRR6024702, SRR6012248 and SRR6008913.

5.
Oncogene ; 18(27): 3954-62, 1999 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-10435618

RESUMEN

Ewing's sarcoma (EWS) cells accumulate elevated steady-state levels of poly (ADP-ribose) polymerase (PARP) mRNA and protein. To understand the molecular mechanisms underlying PARP upregulation, we cloned and analysed the 5'-flanking region of the PARP gene from EWS cells. Nucleotide sequence analysis demonstrated no variations in the PARP promoter region in EWS cells. The PARP promoter encompasses multiple binding motifs for the ETS transcription factor. We have also observed that there is a coordinated up-regulation of the expression of both PARP and ETS1, relative to cells of other human tumor types expressing lower levels of PARP. Transient co-expression of ETS1 in EWS cells resulted in a strong enhancement of PARP-promoter activity. The participation of ETS in the regulation of PARP gene expression was further demonstrated in EWS cells stably transfected with Ets1 antisense cDNA constructs. Antisense-mediated down-regulation of endogenous ETS1 resulted in the inhibition of PARP expression in EWS cells, and sensitized these cells to ionizing radiation. These data provide support for ETS regulation of PARP expression levels, and implicate ETS transcription factors in the radiation response of EWS cells.


Asunto(s)
Poli(ADP-Ribosa) Polimerasas/genética , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas/fisiología , Factores de Transcripción/fisiología , Secuencia de Bases , División Celular/genética , División Celular/efectos de la radiación , Radioisótopos de Cesio , Regulación de la Expresión Génica , Inhibidores de Crecimiento/fisiología , Humanos , Datos de Secuencia Molecular , Poli(ADP-Ribosa) Polimerasas/biosíntesis , Regiones Promotoras Genéticas/fisiología , Proteína Proto-Oncogénica c-ets-1 , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas c-ets , Sarcoma de Ewing/enzimología , Sarcoma de Ewing/genética , Sarcoma de Ewing/patología , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/biosíntesis , Activación Transcripcional , Transfección , Células Tumorales Cultivadas
6.
Oncogene ; 18(51): 7294-302, 1999 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-10602484

RESUMEN

Aberrant communication among growth factors and cytokines that regulate tissue homeostasis often results in malignancy. Among the many cell types that participate in this process, stromal fibroblasts communicate in a paracrine and juxtracrine manner with cells of epithelial, endothelial, and hematopoietic origin. For fibroblasts, platelet-derived growth factor (PDGF) is a major proliferative and differentiation agent. Interleukin-4 (IL-4), however, possesses only modulating functions in this cell type. Here, we investigated the consequences of deleting Stat6 on PDGF and IL-4 signaling, proliferation, and transcriptional activation by establishing and characterizing early passage fibroblasts from wild-type and Stat6 null mice. Both wild-type and Stat6-/- fibroblasts showed nearly identical PDGFR and IL-4R activation, gross substrate tyrosine phosphorylation, PI 3-kinase activation, as well as Stat1, 3 and 5 DNA binding activities. Unexpectedly, IL-4's enhancement of PDGF-induced [3H]thymidine incorporation was greatly diminished in Stat6-/-, but not wild-type fibroblasts. PDGF-induced [3H]thymidine uptake was largely unaffected. Strikingly, IL-4, but not PDGF induction of the proinflammatory gene products, IL-6 and MCP-1 was markedly reduced in Stat6-/- fibroblasts. Thus, Stat6 is an important and specific mediator of IL-4-enhanced PDGF-induced proliferation as well as IL-4's transcriptional activation of IL-6 and MCP-1.


Asunto(s)
Fibroblastos/patología , Fibroblastos/fisiología , Interleucina-4/farmacología , Factor de Crecimiento Derivado de Plaquetas/farmacología , Transducción de Señal/genética , Transactivadores/genética , Activación Transcripcional/genética , Animales , División Celular/efectos de los fármacos , División Celular/genética , Línea Celular Transformada , Eliminación de Gen , Ratones , Factor de Transcripción STAT6 , Transducción de Señal/efectos de los fármacos , Activación Transcripcional/efectos de los fármacos
7.
Vet World ; 8(11): 1370-4, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27047045

RESUMEN

AIM: Tropical theileriosis is fatal hemoprotozoal disease of dairy animals caused by Theileria annulata. The aim of the present study was to detect the T. annulata and comparison of results of molecular and microscopic techniques. MATERIALS AND METHODS: A total of 52 blood samples were collected from the cattle suspected for theileriosis across the Banaskantha district. All the samples were screened for theileriosis using Giemsa's staining technique and polymerase chain reaction (PCR). RESULTS: Total of 17 (32.69%) and 24 (46.15%) samples were found positive for theileriosis by microscopic examination and PCR test, respectively. It revealed that the study area is endemic for theileriosis, and the microscopic technique has 70.83% sensitivity and 100% specificity with respect to PCR technique. CONCLUSION: It may be concluded from the present study that the PCR is comparatively sensitive technique than microscopic examination and may be recommended to use in the field for screening of theileriosis in the study area, where a high prevalence of diseases have been reported due to intensive dairy farming.

8.
Gene ; 193(1): 31-7, 1997 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-9249064

RESUMEN

The mouse homolog of a novel human protein tyrosine kinase encoding gene, A6, was cloned and characterized. The human A6 cDNA is unique in that its gene product exhibited in vitro kinase activity but its predicted amino acid (aa) sequence revealed no consensus motifs commonly found within the kinase domain of protein kinase family members. Here, we isolated a mouse A6 cDNA clone from a murine myeloid progenitor 32D cell library using a 1.1 kb cDNA probe containing the entire human A6 open reading frame (ORF). Determination of the mouse A6 cDNA nucleotide (nt) sequence revealed an ORF of 1050 nt encoding a protein of 350 aa and a molecular mass of 40,201 Da. The mouse and human A6 gene products shared 93% identity. In vitro translation, as well as immunoprecipitation of 32D cell lysates confirmed expression of mouse A6 as a 40 kDa protein. Northern blot analysis of total RNA from mouse cell lines derived from diverse tissues including NIH 3T3 fibroblasts, L cell fibroblasts, C2C12 myoblasts, M1 myeloblasts, BALB/MK cells, 70Z/3 preB lymphocytes, and p388D1 monocytes demonstrated widespread A6 mRNA expression. A6 mRNA was also ubiquitously expressed at varying levels in all tissues examined. The identification of a potential actin/phosphoinositide binding domain and consensus phosphorylation sites, coupled with A6's expression in a variety of cell types suggest that the A6 gene product may play a role in basic cellular processes.


Asunto(s)
Ratones/genética , Proteínas Tirosina Quinasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/enzimología , Humanos , Proteínas de Microfilamentos , Datos de Secuencia Molecular , Biosíntesis de Proteínas , ARN Mensajero/análisis , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Transducción de Señal/genética , Distribución Tisular
9.
Res Microbiol ; 147(3): 159-65, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8761734

RESUMEN

During glucose and xylose fermentation, Thermoanaerobacter finnii was observed to produce lactate, acetate, H2 and CO2, with ethanol being the major end product. Thermoanaerobacter strain SEBR 5268, an isolate from an oil field, also produced a similar range of end products from glucose and xylose fermentation, with the exception that both ethanol and lactate were the major products of sugar metabolism. Both these strains were able to reduce thiosulphate to sulphide in the presence of these two substrates, with acetate being the dominant metabolite in that case. In addition, a faster growth rate and increased cell yield were obtained in the presence of thiosulphate, than in its absence. The higher concentrations of acetate produced in the presence of thiosulphate rather than without any electron acceptor indicated that more ATP was generated from substrate-level phosphorylation. These results have implications for our understanding of the breakdown of carbohydrates present in organic matter found in the natural ecological niches of Thermoanaerobacter species (sulphide-, elemental sulphur- or sulphate-rich thermal hot springs and oil fields).


Asunto(s)
Acetatos/metabolismo , Bacterias Anaerobias/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Glucosa/metabolismo , Bacilos Grampositivos Asporogénicos Irregulares/efectos de los fármacos , Tiosulfatos/farmacología , Xilosa/metabolismo , Bacterias Anaerobias/crecimiento & desarrollo , Bacterias Anaerobias/metabolismo , Bacilos Grampositivos Asporogénicos Irregulares/crecimiento & desarrollo , Bacilos Grampositivos Asporogénicos Irregulares/metabolismo , Técnicas In Vitro , Microbiología del Agua
10.
Metabolism ; 47(5): 603-7, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9591754

RESUMEN

Obese (Lep) gene expression and leptin secretion are regulated by changes in food intake. However, the mechanism by which leptin concentrations are altered by fasting and feeding is unclear. Since these changes occur in parallel with changes in plasma insulin, it is possible that the changes observed are mediated by insulin. To test this hypothesis, we studied the role of insulin in the regulation of Lep gene expression in epididymal fat and leptin secretion during feeding. As shown previously, fasted animals showed significant reductions in Lep mRNA, plasma leptin, and plasma insulin concentrations. Conversely, feeding increased plasma insulin, Lep mRNA, and plasma leptin. In streptozotocin (STZ)-treated animals, plasma insulin concentrations were low. This was associated with low Lep mRNA and plasma leptin concentrations. Changes in food intake, whether fasting or feeding, did not significantly alter plasma insulin levels in STZ-treated animals. Under these circumstances, Lep mRNA and plasma leptin concentrations also remained low. Our results demonstrate that the decrease in Lep mRNA and plasma leptin during fasting and the increase with feeding are dependent on changes in the plasma insulin concentration.


Asunto(s)
Alimentos , Insulina/sangre , Obesidad/sangre , Proteínas/genética , ARN Mensajero/metabolismo , Alimentación Animal , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Interpretación Estadística de Datos , Ingestión de Energía/efectos de los fármacos , Ingestión de Energía/fisiología , Expresión Génica/efectos de los fármacos , Leptina , Masculino , Obesidad/genética , Proteínas/efectos de los fármacos , Proteínas/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Estreptozocina/administración & dosificación , Estreptozocina/farmacología
11.
FEMS Microbiol Lett ; 113(1): 81-6, 1993 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-8243987

RESUMEN

The 16S rRNA gene of the thermophilic sulfate-reducing bacterium Desulfotomaculum thermobenzoicum was amplified by polymerase chain reaction using two eubacterial consensus oligodeoxynucleotide primers flanking the majority of the 16S rRNA gene, cloned, and sequenced. Phylogenetic analysis revealed that D. thermobenzoicum belongs to the Gram-positive (low G + C content) branch and is more related to the thermophilic sulfate-reducing bacterium, D. australicum than the moderate thermophile D. nigrificans, or the mesophiles D. orientis, and D. ruminis. This relationship is further strengthened by the presence of an unusual idiosyncrasy in helix 6 of the 16S rRNA gene of D. thermobenzoicum resembling that of D. australicum but not found in other desulfotomacula species and in any other bacteria sequenced to date.


Asunto(s)
Bacillaceae/genética , ADN Bacteriano/genética , Ligamiento Genético , Filogenia , ARN Ribosómico 16S/genética , Sulfatos , Bacillaceae/clasificación , Secuencia de Bases , Datos de Secuencia Molecular , Oxidación-Reducción , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Especificidad de la Especie
12.
FEMS Microbiol Lett ; 115(1): 33-8, 1994 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-8125244

RESUMEN

A new mesophilic, thermotolerant sulfate-reducing bacterium, was isolated from the flowing bore waters of a deep aquifer, the Great Artesian Basin, Australia. The strain, designated isolate AB16910a, is a curved rod and resembled members of the genus Desulfovibrio. However, the isolate can be differentiated from other members of the Desulfovibrio species because of the high G+C content of 69 +/- 0.25% the 16S rRNA sequence data and other physiological characteristics. The name Desulfovibrio longreachii is proposed for the new isolate.


Asunto(s)
ADN Ribosómico/genética , Desulfovibrio/clasificación , ARN Ribosómico 16S/genética , Microbiología del Agua , Australia , Técnicas de Tipificación Bacteriana , Composición de Base , Secuencia de Bases , ADN Bacteriano/genética , Desulfovibrio/genética , Desulfovibrio/aislamiento & purificación , Desulfovibrio/fisiología , Genes Bacterianos/genética , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN
13.
FEMS Microbiol Lett ; 66(1): 73-8, 1991 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-1936939

RESUMEN

Thirty four Thermus aquaticus strains have been isolated from the non-volcanically naturally heated waters of the Australian Artesian Basin which extends the known ecological habitat of this group of organisms. A simple and rapid method developed for isolation of plasmids indicated that considerable variation in numbers and molecular sizes existed within the 23 strains that were investigated. Dissimilar plasmid profiles were obtained from the strains that been isolated from the source waters and those that had been isolated from the runoff channels formed by these source waters.


Asunto(s)
Thermus/aislamiento & purificación , Microbiología del Agua , Australia , Ecología , Calor , Concentración de Iones de Hidrógeno , Plásmidos , Thermus/genética , Thermus/crecimiento & desarrollo
14.
FEMS Microbiol Lett ; 147(1): 51-6, 1997 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9037763

RESUMEN

A disc-shaped methanogenic bacterium designated strain SEBR 4847T (T = type strain) was isolated from a sample collected from an African offshore oil field. Strain SEBR 4847T was non-motile, had a G + C content of 50 mol% and produced methane from H2 + CO2, formate, and CO2 + propanol. Strain SEBR 4847T grew optimally at 37 degrees C; no growth was observed at 25 degrees C or 45 degrees C. It grew in the presence of up to 50 g/l NaCl; 10-30 g/l was required for optimal growth. The optimum pH for growth was 7.0. Doubling time was about 10 h under optimal conditions. Based on 16S rRNA sequence analysis, the isolate was identified as a new species of the genus Methanoplanus and designated Methanoplanus petrolearius sp. nov. The type strain is SEBR 4847T (= OCM 486).


Asunto(s)
Euryarchaeota/clasificación , Euryarchaeota/aislamiento & purificación , Microbiología del Suelo , Técnicas Bacteriológicas , Clasificación , Medios de Cultivo , Citosina , ADN Bacteriano/análisis , Euryarchaeota/citología , Guanina , Guinea , Datos de Secuencia Molecular , Aceites , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisis , Análisis de Secuencia de ARN
15.
FEMS Microbiol Lett ; 155(2): 185-91, 1997 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-9351200

RESUMEN

An obligately anaerobic spirochete designated strain SEBR 4228T (T = type strain) was isolated from an oil field of Congo, Central Africa. The strain grew optimally with a sodium chloride concentration of 5% (sodium chloride concentration) growth range 1.0-10%) at 37 degrees C (growth temperature range 20-40 degrees C) and pH of 7.0-7.2 (pH growth range pH 5.5-8.0). Strain SEBR 4228T grew on carbohydrates (glucose, fructose, ribose, D-xylose, galactose, mannitol and mannose), glycerol, fumarate, peptides and yeast extract. Yeast extract was required for growth and could not be replaced by vitamins. It reduced thiosulfate and sulfur, to H2S. Glucose was oxidised to lactate, acetate, CO2 and H2S in the presence of thiosulfate but in its absence lactate, ethanol, CO2 and H2 were produced. Fumarate was fermented to acetate and succinate. The G + C content of strain SEBR 4228T was 50%. Strain SEBR 4228T was spiral shaped measuring 5-30 by 0.3-0.5 micron and was motile with a corkscrew-like motion. Electron microscopy revealed the presence of periplasmic flagella in a 1-2-1 arrangement. Strain SEBR 4228T possessed features typical of the members of the genus Spirochaeta. 16S rRNA sequence analysis revealed that it was closely related to Spirochaeta bajacaliforniensis (similarity 98.6%). The lack of DNA homology with S. bajacaliforniensis (38%), together with other phenotypic differences, indicated that strain SEBR 4228T is a new species, which we have designated Spirochaeta smaragdinae. The type strain is SEBR 4228T (= DSM 11293).


Asunto(s)
Spirochaeta/clasificación , ADN Ribosómico/química , Petróleo , ARN Ribosómico 16S/genética , Spirochaeta/citología , Spirochaeta/fisiología
16.
FEMS Microbiol Lett ; 140(2-3): 271-6, 1996 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8764490

RESUMEN

A Gram-negative sporulating thermophilic anaerobe, designated AB11Ad, was isolated from the heated waters of the Great Artesian Basin of Australia. It grew on a variety of carbohydrates including glucose, starch, and dextran and produced a thermostable and thermoactive extracellular endo-dextranase. The enzyme was produced more actively under pH controlled continuous culture conditions than under batch conditions. Ammonium sulfate precipitated crude dextranase exhibited a temperature optimum of 70 degrees C and a pH optimum between 5 and 6. The half life was approximately 6.5 h at 75 degrees C and 2 h at 80 degrees C at pH 5.0 and in the absence of added dextran. 16S rRNA sequence analysis indicated that isolate AB11Ad was a member of the genus Thermoanaerobacter.


Asunto(s)
Bacterias Anaerobias/enzimología , Bacterias Anaerobias/aislamiento & purificación , Dextranasa/metabolismo , Bacilos Grampositivos Asporogénicos Irregulares/enzimología , Bacilos Grampositivos Asporogénicos Irregulares/aislamiento & purificación , Microbiología del Agua , Australia , Bacterias Anaerobias/genética , Metabolismo de los Hidratos de Carbono , Dextranasa/aislamiento & purificación , Estabilidad de Enzimas , Agua Dulce/microbiología , Genes Bacterianos , Bacilos Grampositivos Asporogénicos Irregulares/genética , Semivida , Calor , Datos de Secuencia Molecular , ARN Bacteriano/genética , ARN Ribosómico 16S/genética
17.
FEMS Microbiol Lett ; 134(1): 115-9, 1995 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-8593948

RESUMEN

The 16S rRNA gene (rDNA) sequence analysis of four halophilic anaerobes: Halobacteroides halobius, H. lacunaris. Haloanaerobacter (Hb.) chitinovorans and H. acetoethylicus confirmed that they were all members of the family Haloanaerobiaceae. H. lacunaris and H. halobius were found to be more closely related to each other and were distantly related to Sporohalobacter lortetti and the members of the genera Haloanaerobium and Halothermothrix. These data are in agreement with their assignment to the genus Halobacteroides. Further analysis indicated that Hb. chitinovorans was closely affiliated to members of the genus Halobacteroides, and therefore we propose to transfer it to the genus Halobacteroides as H. chitinovorans comb. nov. This transfer would invalidate the genus Haloanaerobacter, as Hb. chitinovorans is the only member of this genus. The 16S rDNA sequence analysis of H. acetoethylicum indicated that it was very closely related to members of the genus Haloanaerobium, viz. Haloanaerobium (Ha.) praevalens, Ha. salsugo, and Ha. alcaliphilum, and hence we propose to transfer it to the genus Haloanaerobium as Ha. acetoethylicus comb. nov.


Asunto(s)
Bacterias Anaerobias Gramnegativas/clasificación , Bacterias Anaerobias Gramnegativas/genética , Filogenia , ARN Ribosómico 16S/genética , Composición de Base , Secuencia de Bases , ADN Bacteriano/genética , Genes Bacterianos/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
18.
FEMS Microbiol Lett ; 150(1): 9-18, 1997 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-9163900

RESUMEN

Bacterial specific primers were used to amplify 23S rRNA genes from a representative strain from each of the 23 serogroups of the pathogenic Leptospira interrogans and 8 strains from 6 serogroups of the non-pathogenic Leptospira biflexa. Only regions of extreme variability, which had been identified on the basis of homology-based search of all the 23S rRNA sequences available in GenBank database, were sequenced from the amplified products. PCR primers that had the potential to distinguish L. interrogans from L. biflexa species were designed from the derived sequences and a sensitive PCR protocol developed. The PCR method enabled the differentiation of the 59 strains of the 23 serogroups of L. interrogans from the 8 strains of 6 serogroups of L. biflexa. Further investigation by 16S rDNA sequencing of two strains of L. interrogans, which gave unexpected PCR results, provided evidence that they had been misclassified and hence we propose to reassign them to L. biflexa.


Asunto(s)
ADN Bacteriano/genética , Leptospira interrogans/genética , Leptospira/genética , Reacción en Cadena de la Polimerasa/métodos , ARN Ribosómico 23S/genética , Secuencia de Bases , Cartilla de ADN , Leptospira/patogenicidad , Leptospira interrogans/patogenicidad , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Especificidad de la Especie
19.
FEMS Microbiol Lett ; 142(1): 85-90, 1996 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-8759793

RESUMEN

The PCR amplification of the genomic DNA of Leptonema illini strain 3055 using primers directed against conserved regions of the rRNA operon provided evidence that the 16S and 23S rRNA genes were linked via an intergenic spacer region. The sequencing of the intergenic spacer region indicated that it was 435 nucleotides in length and sequence similarity searches revealed that it bore no homology to any known sequences including tRNA available in databases. Further investigations using Southern blot hybridization revealed that there were two copies of these linked genes in the genome. However, similar PCR studies on a representative strain from each of the 23 serogroups of Leptospira interrogans, which are pathogenic, and eight strains from the 6 serogroups of Leptospira biflexa, which are non-pathogenic, revealed that the 16S and 23S rRNA genes were not linked.


Asunto(s)
ADN Bacteriano/genética , ADN Ribosómico/genética , Leptospira/genética , Leptospiraceae/genética , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Secuencia de Bases , Cartilla de ADN/genética , Ligamiento Genético , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , ARN Bacteriano/genética , Especificidad de la Especie
20.
FEMS Microbiol Lett ; 147(1): 81-8, 1997 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9037768

RESUMEN

A strictly anaerobic, moderately halophilic, Gram-negative, non-motile rod-shaped bacterium was isolated from an oil-well head sample of an offshore Congolese oil field. The strain, designated SEBR 4224T (T = type strain), grew optimally at 42 degrees C and pH 7.0 in a complex medium containing 10% NaCl with a generation time of 2.5 h. Strain SEBR 4224T grew on a range of carbohydrates including fructose, galactose, D-glucose, maltose, D-mannose, D-ribose, sucrose, and trehalose. Yeast extract and/or bio-Trypcase was required for growth on carbohydrates and could not be replaced with amino acids and/or vitamins. The end-products from glucose fermentation were acetate, H2, and CO2. Thiosulfate and elemental sulfur were used as electron acceptors. Thiosulfate improved carbohydrate utilization and biomass yields. The G + C content of the isolate was 34 mol%. Ribosomal 16S rRNA sequence analysis showed that strain SEBR 4224T is a new member of the genus Haloanaerobium. The lack of DNA homology with H. acetoethylicum, its closest relative, as determined by DNA-DNA hybridization supports the designation of strain SEBR 4224T as a new species, Haloanaerobium congolense sp. nov. The type strain is SEBR 4224T (= DSM 11287).


Asunto(s)
Bacterias Anaerobias Gramnegativas/clasificación , Sales (Química)/metabolismo , Microbiología del Suelo , Azufre/metabolismo , Tiosulfatos/metabolismo , Técnicas Bacteriológicas , Metabolismo de los Hidratos de Carbono , Pared Celular/ultraestructura , Clasificación , Congo , Citosina , ADN Bacteriano/análisis , Fermentación , Genotipo , Bacterias Anaerobias Gramnegativas/genética , Bacterias Anaerobias Gramnegativas/metabolismo , Guanina , Microscopía Electrónica , Datos de Secuencia Molecular , Aceites , Fenotipo , Filogenia , ARN Ribosómico 16S/análisis , Análisis de Secuencia de ADN
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