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1.
World J Microbiol Biotechnol ; 36(2): 29, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32016527

RESUMEN

Short-chain halogenated aliphatic hydrocarbons (e.g. perchloroethene, trichloroethene) are among the most toxic environmental pollutants. Perchloroethene and trichloroethene can be dechlorinated to non-toxic ethene through reductive dechlorination by Dehalococcoides sp. Bioaugmentation, applying cultures containing organohalide-respiring microorganisms, is a possible technique to remediate sites contaminated with chlorinated ethenes. Application of site specific inocula is an efficient alternative solution. Our aim was to develop site specific dechlorinating microbial inocula by enriching microbial consortia from groundwater contaminated with trichloroethene using microcosm experiments containing clay mineral as solid phase. Our main goal was to develop fast and reliable method to produce large amount (100 L) of bioactive agent with anaerobic fermentation technology. Polyphasic approach has been applied to monitor the effectiveness of dechlorination during the transfer process from bench-scale (500 mL) to industrial-scale (100 L). Gas chromatography measurement and T-RFLP (Terminal Restriction Fragment Length Polymorphism) revealed that the serial subculture of the enrichments shortened the time-course of the complete dechlorination of trichloroethene to ethene and altered the composition of bacterial communities. Complete dechlorination was observed in enrichments with significant abundance of Dehalococcoides sp. cultivated at 8 °C. Consortia incubated in fermenters at 18 °C accelerated the conversion of TCE to ethene by 7-14 days. Members of the enrichments belong to the phyla Bacteroidetes, Chloroflexi, Proteobacteria and Firmicutes. According to the operational taxonomic units, main differences between the composition of the enrichment incubated at 8 °C and 18 °C occurred with relative abundance of acetogenic and fermentative species. In addition to the temperature, the site-specific origin of the microbial communities and the solid phase applied during the fermentation technique contributed to the development of a unique microbial composition.


Asunto(s)
Anaerobiosis/fisiología , Bacterias/metabolismo , Biodegradación Ambiental , Arcilla/química , Microbiota/fisiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Bacteroidetes/genética , Bacteroidetes/metabolismo , Chloroflexi/genética , Chloroflexi/metabolismo , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Fermentación , Firmicutes/genética , Firmicutes/metabolismo , Geobacter/genética , Geobacter/metabolismo , Agua Subterránea/microbiología , Consorcios Microbianos , Polimorfismo de Longitud del Fragmento de Restricción , Proteobacteria/genética , Proteobacteria/metabolismo , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/aislamiento & purificación , Tricloroetileno/química , Microbiología del Agua , Contaminantes Químicos del Agua/metabolismo
2.
Zool Res ; 41(1): 20-31, 2020 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-31930784

RESUMEN

There is a growing appreciation for the specific health benefits conferred by commensal microbiota on their hosts. Clinical microbiota analysis and animal studies in germ-free or antibiotic-treated mice have been crucial for improving our understanding of the role of the microbiome on the host mucosal surface; however, studies on the mechanisms involved in microbiome-host interactions remain limited to small animal models. Here, we demonstrated that rhesus monkeys under short-term broad-spectrum antibiotic treatment could be used as a model to study the gut mucosal host-microbiome niche and immune balance with steady health status. Results showed that the diversity and community structure of the gut commensal bacteria in rhesus monkeys were both disrupted after antibiotic treatment. Furthermore, the 16S rDNA amplicon sequencing results indicated that Escherichia-Shigella were predominant in stool samples 9 d of treatment, and the abundances of bacterial functional genes and predicted KEGG pathways were significantly changed. In addition to inducing aberrant morphology of small intestinal villi, the depletion of gut commensal bacteria led to increased proportions of CD3 + T, CD4 + T, and CD16 + NK cells in peripheral blood mononuclear cells (PBMCs), but decreased numbers of Treg and CD20 + B cells. The transcriptome of PBMCs from antibiotic-treated monkeys showed that the immune balance was affected by modulation of the expression of many functional genes, including IL-13, VCAM1, and LGR4.


Asunto(s)
Disbiosis/inmunología , Microbioma Gastrointestinal , Intestinos/anatomía & histología , Macaca mulatta/microbiología , Animales , Antibacterianos/farmacología , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/genética , ADN Bacteriano/genética , Heces/microbiología , Intestinos/microbiología , Masculino
3.
Microbes Environ ; 35(1)2020.
Artículo en Inglés | MEDLINE | ID: mdl-31932537

RESUMEN

Vigna is a genus of legumes cultivated in specific areas of tropical countries. Species in this genus are important crops worldwide. Vigna species are of great agronomic interest in Venezuela because Vigna beans are an excellent alternative to other legumes. However, this type of crop has some cultivation issues due to sensitivity to acidic soils, high temperatures, and salinity stress, which are common in Venezuela. Vigna species establish symbioses mainly with Bradyrhizobium and Ensifer, and Vigna-rhizobia interactions have been examined in Asia, Africa, and America. However, the identities of the rhizobia associated with V. radiata and V. unguiculata in Venezuela remain unknown. In the present study, we isolated Venezuelan symbiotic rhizobia associated with Vigna species from soils with contrasting agroecosystems or from fields in Venezuela. Several types of soils were used for bacterial isolation and nodules were sampled from environments characterized by abiotic stressors, such as high temperatures, high concentrations of NaCl, and acidic or alkaline pH. Venezuelan Vigna-rhizobia were mainly fast-growing. Sequencing of several housekeeping genes showed that in contrast to other continents, Venezuelan Vigna species were nodulated by rhizobia genus including Burkholderia, containing bacteria from several new phylogenetic lineages within the genus Bradyrhizobium. Some Rhizobium and Bradyrhizobium isolates were tolerant of high salinity and Al toxicity. The stress tolerance of strains was dependent on the type of rhizobia, soil origin, and cultivation history. An isolate classified as R. phaseoli showed the highest plant biomass, nitrogen fixation, and excellent abiotic stress response, suggesting a novel promising inoculant for Vigna cultivation in Venezuela.


Asunto(s)
Filogenia , Proteobacteria/clasificación , Proteobacteria/fisiología , Microbiología del Suelo , Simbiosis , Vigna/microbiología , ADN Bacteriano/genética , Genes Bacterianos/genética , Fijación del Nitrógeno/genética , Proteobacteria/genética , Proteobacteria/aislamiento & purificación , ARN Ribosómico 16S/genética , Nódulos de las Raíces de las Plantas/microbiología , Análisis de Secuencia de ADN , Suelo/química , Estrés Fisiológico , Venezuela , Vigna/crecimiento & desarrollo
4.
Forensic Sci Int ; 306: 110077, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31821940

RESUMEN

Forensic samples are commonly influenced by various environmental factors, including ultraviolet (UV) irradiation; thus, forensic applications of DNA repair (e.g., PreCR™, Restorase®) have been investigated, focusing on short tandem repeat typing. However, current DNA-based examinations are used for both human and body fluid identification. This study thus aims to clarify the efficacy of a DNA repair approach for Streptococcus salivarius DNA-based identification of saliva from UV-damaged samples. Artificial UV-damaged genomic DNA of S. salivarius, drop saliva stains, and buccal swabs were used to evaluate the effects of DNA repair on S. salivarius DNA detection by using PreCR™ repair reagent. To evaluate forensic applications, we prepared mock forensic samples by exposing them to environmental conditions. Melting curve analysis following real-time PCR was applied for qualitatively detecting S. salivarius DNA with a specific melting peak of 80.5°C±0.4°C (n=10, mean ± 3SD). Single PCR was used for quantitative and qualitative analyses, whereas dual PCR was used for S. salivarius DNA qualitative detection. DNA repair experiments using artificial UV-damaged samples revealed a significant increase of only the quantitative value of genomic DNA samples by DNA repair. Moreover, significant quantitative DNA repair effects were not observed in all mock forensic samples, indicating the limitations of DNA repair for actual cell-derived DNA samples. Whereas, differences of qualitative results (with or without detection) were generated for mock forensic samples; thus, we consider the DNA repair strategy as an additional approach for S. salivarius DNA-based identification of saliva from environmentally damaged evidence.


Asunto(s)
Reparación del ADN , Saliva/microbiología , Streptococcus salivarius/genética , Rayos Ultravioleta/efectos adversos , Daño del ADN , ADN Bacteriano/genética , Humanos , Indicadores y Reactivos , Repeticiones de Microsatélite , Reacción en Cadena en Tiempo Real de la Polimerasa
5.
Arch Microbiol ; 202(1): 191-196, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31595323

RESUMEN

A novel Gram-negative, aerobic, rod-shaped bacterium, RS19T, was isolated from rose rhizosphere soil. The strain was psychrophilic and showed good growth over a temperature range of 1-37 â„ƒ. Colonies on TSB agar were circular, smooth, mucoid, convex with clear edges and yellow. Phylogenetic analysis based on 16S rRNA gene sequences characterized RS19T in the genus Dyadobacter and showed that strain RS19T was most closely related to Dyadobacter psychrophilus CGMCC 1.8951T (97.4%) and Dyadobacter alkalitolerans CGMCC 1.8973T (97.1%). The average nucleotide identity values to the closest related species type strains were less than 84.0%. The DNA G + C content was 43.1 mol%, and the predominant respiratory menaquinone was MK-7. The major fatty acids were summed features 3 (C16:1ω7c and/or C16:1ω6c), iso-C15:0, C16:1ω5c and iso-C17:0 3-OH. Based on genotypic, phenotypic and chemotaxonomic data, strain RS19T is different from closely related species of the genus Dyadobacter. RS19T represents a novel species within the genus Dyadobacter, for which the name Dyadobacter luteus sp. nov. is proposed. The type strain is RS19T (= CGMCC 1.13719T = ACCC 60381T = JCM 32940T).


Asunto(s)
Cytophagaceae/clasificación , Filogenia , Rizosfera , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , Cytophagaceae/química , Cytophagaceae/genética , ADN Bacteriano/genética , Ácidos Grasos/análisis , ARN Ribosómico 16S/genética , Rosa/microbiología , Análisis de Secuencia de ADN , Especificidad de la Especie , Vitamina K 2/análisis
6.
Arch Microbiol ; 202(1): 127-134, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31515591

RESUMEN

A novel bacterial strain, designated ZR32T, was isolated from briquette warehouse soil in Ulsan (Korea). The strain was aerobic, showing pink-colored colonies on R2A agar. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain ZR32T was closely related to Mucilaginibacter soli R9-65T (97.0%), Mucilaginibacter gynuensis YC7003T (96.9%), and Mucilaginibacter lutimaris BR-3T (96.8%). The values of DNA-DNA relatedness related two highest strains M. soli R9-65T and M. gynuensis YC7003T were 31.2 ± 6.9% and 19.7 ± 0.3%, respectively. Its genome size was 3.9 Mb, comprising 3402 predicted genes. The DNA G+C content of strain ZR32T was 43.0 mol%. The major cellular fatty acids (> 5% of total) were summed feature 3 (C16:1ω6c and/or C16:1ω7c), C16:0, C16:1ω5c, iso-C15:0, iso-C17:0 3-OH, and C17:1ω9c. The major respiratory quinine was menaquinone-7 (MK-7). The major polar lipids were phosphatidylethanolamine, two unidentified phospholipids, one unidentified sphingolipid, and one unidentified polar lipid. Strain ZR32T showed distinctive characteristics such as the temperature and pH for growth ranges, being positive for ß-glucosidase, salicin production, negative for N-acetyl-glucosamine assimilation, being resistant to carbenicillin and piperacillin to related species. On the basis of phenotypic, chemotaxonomic, and phylogenetic data, strain ZR32T represents a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter hurinus sp. nov. is proposed. The type strain is ZR32T (= KCTC 62193 = CCTCC AB 2017285).


Asunto(s)
Bacteroidetes/clasificación , Filogenia , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Bacteroidetes/química , Bacteroidetes/genética , Composición de Base , ADN Bacteriano/genética , Lípidos/análisis , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Especificidad de la Especie
7.
Arch Microbiol ; 202(1): 143-151, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31535159

RESUMEN

A gram-stain-negative, aerobic, non-spore-forming, rod-shaped, non-motile bacterium strain R4HLG17T was isolated from Tamarix ramosissima roots growing in Kumtag desert. The strain grew at salinities of 0-16% (w/v) NaCl (optimum 5-6%), pH 5-9 (optimum 7) and at 16-45 °C. Based on 16S rRNA gene sequence similarity, strain R4HLG17T belonged to the family Halomonadaceae and was most closely related to Halomonas lutea DSM 23508T(95.1%), followed by Halotalea alkalilenta AW-7T(94.8%), Salinicola acroporae S4-41T(94.8%), Salinicola halophilus CG4.1T(94.6%), and Larsenimonas salina M1-18T(94.4%). Multilocus sequence analysis (MLSA) based on the partial sequences of 16S rRNA, atpA, gyrB, rpoD, and secA genes indicated that the strain R4HLG17T formed an independent and monophyletic branch related to other genera of Halomonadaceae, supporting its placement as a new genus in this family. The draft genome of strain R4HLG17T was 3.6 Mb with a total G + C content of 55.1%. The average nucleotide identity to Halomonas lutea DSM 23508T was 83.5%. Q-9 was detected as the major respiratory quinone and summed feature 8 (C18:1ω7c/C18:1ω6c), summed feature 3 (C16:1ω7c/C16:1ω6c), and C16:0 as predominant cellular fatty acids. On the basis of chemotaxonomic, phylogenetic, and phenotypic evidence, strain R4HLG17T is concluded to represent a novel species of a new genus within Halomonadaceae, for which the name Phytohalomonas tamaricis gen. nov., sp. nov., is proposed. The type strain is R4HLG17T (=ACCC 19929T=KCTC 52415T).


Asunto(s)
Halomonadaceae/clasificación , Raíces de Plantas/microbiología , Tamaricaceae/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Clima Desértico , Ácidos Grasos/análisis , Halomonadaceae/química , Halomonadaceae/genética , Tipificación de Secuencias Multilocus , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie
8.
Arch Microbiol ; 202(1): 55-61, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31463600

RESUMEN

A novel actinomycete, strain PA1-10T, isolated from the leaf of Phyllanthus amarus collected from Bangkok, Thailand, was characterized taxonomically using a polyphasic approach. This strain contained the characteristics consistent with those of members of the genus Nonomuraea. It formed short rugose spore chain on aerial mycelium. The diamino acid in cell wall peptidoglycan was meso-diaminopimelic acid. Galactose, glucose, madurose, mannose, and ribose were found in whole-cell hydrolysates. Predominant menaquinones were MK-9 (H2), MK-9 (H4), and MK-9 (H6). Major cellular fatty acids were iso-C16:0 and C17:0 10-methyl. Phospholipid profiles were composed of phosphatidylinositol mannoside (PIM), lyso-phosphatidylethanolamine (lyso-PE), phosphatidylethanolamine (PE), methylphosphatidylethanolamine (PME), diphosphatidylglycerol (DPG), and phosphatidylglycerol (PG). The G + C content of DNA was 71.2 mol%. Strain PA1-10T showed the highest 16S rRNA gene sequence similarity with Nonomuraea candida JCM 15928T (98.35%) and shared the same node with Nonomuraea maritima JCM 18321T in the phylogenetic tree analysis. Based on the phenotypic characteristics, DNA-DNA relatedness, and average nucleotide identity (ANI), the strain is considered to represent a novel species of the genus Nonomuraea, for which the name Nonomuraea phyllanthi is proposed. The type strain is PA1-10T (= JCM 33073T = NBRC 112774T = TISTR 2497T).


Asunto(s)
Actinomycetales/clasificación , Phyllanthus/microbiología , Filogenia , Hojas de la Planta/microbiología , Actinomycetales/química , Actinomycetales/genética , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Tailandia
9.
Food Microbiol ; 85: 103280, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31500706

RESUMEN

Listeria monocytogenes causes severe diseases in humans, including febrile gastroenteritis and systemic infections that has a high mortality despite antibiotic treatment. This pathogen may cause massive outbreaks associated to the consumption of contaminated food products, which highlight its importance in public health. In the last decade, L. monocytogenes has emerged as a foodborne pathogen of major importance in Chile. A previous work showed that in Chile during 2008 and 2009, L. monocytogenes serotypes 1/2a, 1/2b and 4b were the most frequently identified in food and clinical strains. Here we report the molecular characterization of L. monocytogenes strains isolated from 2008 to 2017 in the country. Our results indicate that serotypes 1/2a, 1/2b and 4b continue to be the most commonly found in food products. In addition, we identify persistent and widespread PFGE subtypes. This study reports ten years of epidemiological surveillance ofL. monocytogenes in Chile.


Asunto(s)
Monitoreo Epidemiológico , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos/epidemiología , Listeria monocytogenes/genética , Listeriosis/epidemiología , Chile/epidemiología , Recuento de Colonia Microbiana , ADN Bacteriano/genética , Brotes de Enfermedades , Enfermedades Transmitidas por los Alimentos/microbiología , Gastroenteritis/epidemiología , Gastroenteritis/microbiología , Variación Genética , Humanos , Listeria monocytogenes/patogenicidad , Productos de la Carne/microbiología , Epidemiología Molecular , Salud Pública , Serogrupo , Serotipificación , Factores de Virulencia/genética
10.
Food Microbiol ; 85: 103302, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31500708

RESUMEN

This study dealt with the influence of the temperature on the bacterial dynamics of two spontaneously fermented wheat sourdoughs, propagated at 21 ±â€¯1 °C (SD1) and 30 ±â€¯1 °C (SD2), during nine backslopping steps (BS1 to BS9). Proteobacteria was the only phylum found in flour. Escherichia hermannii was predominant, followed by Kosakonia cowanii, besides species belonging to the genera Pantoea and Pseudomonas. After one step of propagation, Clostridium and Bacillus cereus group became predominant. Lactobacillus curvatus was found at low relative abundance. For the second backslopping step, Clostridium was flanked by L. curvatus and Lactobacillus farciminis. From BS4 (6th day) onward, lactic acid bacteria (LAB) became predominant. L. farciminis overcame L. curvatus and remained dominant until the end of propagations for both sourdoughs. At 21 °C, Bacillus, Clostridium, Pseudomonas, and Enterobacteriaceae were gradually inhibited. At the end of propagation, SD1 harbored only LAB. Otherwise, the temperature of 30 °C favored the persistence of atypical bacteria in SD2, as Pseudomonas and Enterobacteriaceae. Therefore, the temperature of 21 °C was more suitable for sourdough propagation in Brazil. This study enhanced the knowledge of temperature's influence on microbial assembly and contributed to the elucidation of sourdough microbial communities in Brazil.


Asunto(s)
Pan/microbiología , Fermentación , Metagenoma , Proteobacteria/clasificación , Brasil , Recuento de Colonia Microbiana , ADN Bacteriano/genética , Harina/microbiología , Variación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Microbiota , Proteobacteria/crecimiento & desarrollo , ARN Ribosómico 16S/genética , Temperatura Ambiental
11.
Pol J Microbiol ; 68(4): 429-438, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31880887

RESUMEN

Penaeus monodon is highly susceptible to vibriosis disease. Aims of the study were to identify the pathogen causing vibriosis in P. monodon through molecular techniques and develop a biocontrol method of the disease by application of herbal extracts. Shrimp samples were collected aseptically from the infected farm and the bacteria were isolated from the infected region of those samples. Based on phenotypic identification, several isolates were identified as Vibrio sp. 16S rRNA gene sequences of the selected isolates exhibited 100% homology with V. alginolyticus strain ATCC 17749. An in vivo infection challenge test was performed by immersion method with V. alginolyticus where these isolates caused high mortality in juvenile shrimp with prominent symptoms of hepatopancreatic necrosis. Antibiogram profile of the isolates was determined against eleven commercial antibiotic discs whereas the isolates were found resistant to multiple antibiotics. A total of twenty-one herbal extracts were screened where Emblica officinalis, Allium sativum, and Syzygium aromaticum strongly inhibited the growth of V. alginolyticus in in vitro conditions. In in vivo conditions, the ethyl acetate extracts of E. officinalis and A. sativum successfully controlled the vibriosis disease in shrimp at a dose of 10 mg/g feed. This is the first report on molecular identification and biocontrol of V. alginolyticus in shrimp in Bangladesh.Penaeus monodon is highly susceptible to vibriosis disease. Aims of the study were to identify the pathogen causing vibriosis in P. monodon through molecular techniques and develop a biocontrol method of the disease by application of herbal extracts. Shrimp samples were collected aseptically from the infected farm and the bacteria were isolated from the infected region of those samples. Based on phenotypic identification, several isolates were identified as Vibrio sp. 16S rRNA gene sequences of the selected isolates exhibited 100% homology with V. alginolyticus strain ATCC 17749. An in vivo infection challenge test was performed by immersion method with V. alginolyticus where these isolates caused high mortality in juvenile shrimp with prominent symptoms of hepatopancreatic necrosis. Antibiogram profile of the isolates was determined against eleven commercial antibiotic discs whereas the isolates were found resistant to multiple antibiotics. A total of twenty-one herbal extracts were screened where Emblica officinalis, Allium sativum, and Syzygium aromaticum strongly inhibited the growth of V. alginolyticus in in vitro conditions. In in vivo conditions, the ethyl acetate extracts of E. officinalis and A. sativum successfully controlled the vibriosis disease in shrimp at a dose of 10 mg/g feed. This is the first report on molecular identification and biocontrol of V. alginolyticus in shrimp in Bangladesh.


Asunto(s)
Conservantes de Alimentos/farmacología , Penaeidae/microbiología , Extractos Vegetales/farmacología , Plantas Medicinales/química , Mariscos/microbiología , Vibrio alginolyticus/efectos de los fármacos , Vibrio alginolyticus/genética , Animales , Antibacterianos/farmacología , ADN Bacteriano/genética , Conservación de Alimentos , Pruebas de Sensibilidad Microbiana , Penaeidae/crecimiento & desarrollo , ARN Ribosómico 16S/genética , Vibrio alginolyticus/crecimiento & desarrollo , Vibrio alginolyticus/aislamiento & purificación
12.
Pol J Microbiol ; 68(4): 465-476, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31880891

RESUMEN

The associated microbiota plays an essential role in the life process of jellyfish. The endobiotic bacterial communities from four common jellyfish Phyllorhiza punctata, Cyanea capillata, Chrysaora melanaster, and Aurelia coerulea were comparatively analyzed by 16S rDNA sequencing in this study. Several 1049 OTUs were harvested from a total of 130 183 reads. Tenericutes (68.4%) and Firmicutes (82.1%) are the most abundant phyla in P. punctata and C. melanaster, whereas C. capillata and A. coerulea share the same top phylum Proteobacteria (76.9% vs. 78.3%). The classified OTUs and bacterial abundance greatly decrease from the phylum to genus level. The top 20 matched genera only account for 9.03% of the total community in P. punctata, 48.9% in C. capillata, 83.05% in C. melanaster, and 58.1% in A. coerulea, respectively. The heatmap of the top 50 genera shows that the relative abundances in A. coerulea and C. capillata are far richer than that in P. punctata and C. melanaster. Moreover, a total of 41 predictive functional categories at KEGG level 2 were identified. Our study indicates the independent diversity of the bacterial communities in the four common Scyphomedusae, which might involve in the metabolism and environmental information processing of the hosts.The associated microbiota plays an essential role in the life process of jellyfish. The endobiotic bacterial communities from four common jellyfish Phyllorhiza punctata, Cyanea capillata, Chrysaora melanaster, and Aurelia coerulea were comparatively analyzed by 16S rDNA sequencing in this study. Several 1049 OTUs were harvested from a total of 130 183 reads. Tenericutes (68.4%) and Firmicutes (82.1%) are the most abundant phyla in P. punctata and C. melanaster, whereas C. capillata and A. coerulea share the same top phylum Proteobacteria (76.9% vs. 78.3%). The classified OTUs and bacterial abundance greatly decrease from the phylum to genus level. The top 20 matched genera only account for 9.03% of the total community in P. punctata, 48.9% in C. capillata, 83.05% in C. melanaster, and 58.1% in A. coerulea, respectively. The heatmap of the top 50 genera shows that the relative abundances in A. coerulea and C. capillata are far richer than that in P. punctata and C. melanaster. Moreover, a total of 41 predictive functional categories at KEGG level 2 were identified. Our study indicates the independent diversity of the bacterial communities in the four common Scyphomedusae, which might involve in the metabolism and environmental information processing of the hosts.


Asunto(s)
Bacterias/aislamiento & purificación , Biodiversidad , Escifozoos/microbiología , Animales , Bacterias/clasificación , Bacterias/genética , ADN Bacteriano/genética , Microbiota , Filogenia , ARN Ribosómico 16S/genética , Escifozoos/clasificación
13.
Pol J Microbiol ; 68(4): 559-563, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31880899

RESUMEN

We demonstrate here for the first time the use of an IncP-1ß plasmid, R751, as a gene capture vehicle for recombineering/conjugation strategies to clone large segments of bacterial genomes (20 - 100 + Kb). We designed R751 derivatives containing alternative markers for greater flexibility when using the R751 vehicle across different bacteria. These markers are removable if desired as part of the cloning procedure (with no extra steps needed). We demonstrated utility via cloning of 38 and 22 kb genomic segments from Salmonella enterica serovar Typhimurium and Escherichia coli, respectively. The plasmids expand the options available for use in recombineering/conjugation-based cloning applications.We demonstrate here for the first time the use of an IncP-1ß plasmid, R751, as a gene capture vehicle for recombineering/conjugation strategies to clone large segments of bacterial genomes (20 ­ 100 + Kb). We designed R751 derivatives containing alternative markers for greater flexibility when using the R751 vehicle across different bacteria. These markers are removable if desired as part of the cloning procedure (with no extra steps needed). We demonstrated utility via cloning of 38 and 22 kb genomic segments from Salmonella enterica serovar Typhimurium and Escherichia coli, respectively. The plasmids expand the options available for use in recombineering/conjugation-based cloning applications.


Asunto(s)
Clonación Molecular , Conjugación Genética , Escherichia coli/genética , Plásmidos/genética , Salmonella typhimurium/genética , ADN Bacteriano/genética , Recombinación Genética
14.
BMC Infect Dis ; 19(1): 1009, 2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31779587

RESUMEN

BACKGROUND: Although Streptococcus agalactiae is the leading causative agent of neonatal sepsis and meningitis, recently it is increasingly isolated from non-pregnant adults. The relation between its presence in the genitourinary tract and manifested clinical symptoms of STD patients remains an open question. In this study, a complex epidemiological investigation of GBS isolates from a venerology clinic was performed. METHODS: Ninety-six GBS isolates were serotyped and their genetic relatedness determined by PFGE. MLST was also performed for a subset of 20 isolates. The antibiotic susceptibility was tested with agar dilution. Surface proteins and the ST-17 hypervirulent clone was detected by PCR. RESULTS: The serotype prevalence was the following: V (29.2%), III (27.1%), Ia (22.9%), IV (10.4%), II (5.2%) and Ib (4.2%). A strong association was demonstrated between surface protein genes and serotypes. All isolates were fully susceptible to penicillin, but erythromycin and clindamycin resistance was high (41.7 and 35.4%, respectively), and 8 phenotypically macrolide sensitive isolates carried the ermB gene. 21.9% of all strains belonged to the hypervirulent ST17 clone, most being of serotype III and all were rib +. We found a few serotype IV isolates belonging to several STs and one serotype V/ST110 strain, containing a 44-bp deletion in the atr allele. CONCLUSIONS: The presence of silent ermB genes is of worry, as their expression upon macrolide exposure could lead to unforeseen therapeutic failure, while clindamycin is used for intrapartum antibiotic prophylaxis, in case of penicillin allergy. The other alarming result is the high prevalence of ST17 among these strains from STD patients, who could be sources of further infections. This is the first report from Hungary providing both serotyping and genotyping data of GBS isolates. These results could be helpful for vaccine production as the major vaccine candidates are capsular antigens or surface proteins.


Asunto(s)
Infecciones Estreptocócicas/diagnóstico , Streptococcus agalactiae/genética , Adulto , Antibacterianos/farmacología , Proteínas Bacterianas/genética , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Farmacorresistencia Bacteriana/efectos de los fármacos , Femenino , Humanos , Hungría/epidemiología , Macrólidos/farmacología , Pruebas de Sensibilidad Microbiana , Fenotipo , Prevalencia , Serogrupo , Infecciones Estreptocócicas/epidemiología , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/aislamiento & purificación , Streptococcus agalactiae/patogenicidad , Virulencia/genética
15.
J Microbiol ; 57(12): 1079-1085, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31758394

RESUMEN

A yellow pigmented, Gram-stain-negative, strictly aerobic, rod-shaped, motile by means of gliding, catalase and oxidase positive bacterium, designated strain DS2-AT, was isolated from soil. Growth was observed at 4-32°C (optimum, 28°C), pH 6-9 (optimum, 7.0), and with 0-0.25% (w/v) NaCl (optimum, 0%). Phylogenetic analysis of 16S rRNA gene sequence revealed that strain DS2-AT belonged to the genus Flavobacterium and was most closely related to Flavobacterium aquatile LMG 4008T (96.4%), Flavobacterium terrae DSM 18829T (95.6%), Flavobacterium vireti THG-SM1T (95.5%), Flavobacterium inkyongense IMCC27201T (95.4%), Flavobacterium brevivitae TTM-43T (95.2%), and Flavobacterium cucumis DSM 18830T (95.2%). Strain DS2-AT produces flexirubin-type pigments. The major fatty acids were iso-C15:0, iso-C17:0 3-OH, and iso-C15:0 3-OH. The major respiratory quinone was identified as menaquinone-6. The major polar lipid was found to be phosphatidylethanolamine. The average nucleotide identity values between strain DS2-AT and selected taxa, F. aquatile LMG 4008T, F. terrae DSM 18829T, and F. cucumis DSM 18830T, were 72, 72.7, and 71.6%, respectively. The draft genome of strain DS2-AT has a number of 14 contigs, scaffold N50 of 476,310 bp and a total size of 3,563,867 bp. Additionally, strain DS2-AT contains 3,127 of gene, 41 of tRNA, 6 of rRNA, and 3 of ncRNA. The DNA G + C content of stain DS2-AT was 40.7 mol%. Based on phylogenetic and phenotypic analyses, strain DS2-AT is considered as a novel species of the genus Flavobacterium, for which the name Flavobacterium humi sp. nov., (type strain DS2-AT = KACC 19715T = JCM 32786T) has been proposed.


Asunto(s)
Flavobacterium/clasificación , Flavobacterium/aislamiento & purificación , Flavobacterium/metabolismo , Filogenia , Pigmentos Biológicos/metabolismo , Polienos/metabolismo , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/análisis , Flavobacterium/genética , Hibridación de Ácido Nucleico , Fosfatidiletanolaminas/análisis , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Suelo , Vitamina K 2/análogos & derivados , Vitamina K 2/análisis
17.
J Microbiol ; 57(12): 1073-1078, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31680219

RESUMEN

A strictly anaerobic bacterium, designated as strain KGMB-03357T, was isolated from the faeces of a healthy Korean selected by Bundang Seoul National University based on health status. Cells of strain KGMB03357T are Gram-stain-positive, non-motile, non-spore-forming, and observed as straight or curved rods. The isolate grew at 10-45°C (optimum temperature of 40°C) and a pH range of 5.1-10.5 (optimum pH of 6.8). Analysis of phylogenetic trees based on the 16S rRNA gene sequences revealed that strain KGMB03357T forms a lineage within the genus Anaerotignum, and is most closely related to Anaerotignum lactatifermentans G17T (= KCTC 15066T, 96.1%), Anaerotignum propionicum DSM 1682T (= KCTC 5582T, 94.9%), Anaerotignum neopropionicum DSM 03847T (= KCTC 15564T, 94.9%), and Anaerotignum aminivorans SH021T (= KCTC 15705T, 94.8%). The ANI values between strain KGMB 03357T and members of the genus Anaerotignum were 73.3-71.0%, which are below the ANI criterion for interspecies identity. The DNA G + C content based on the whole-genome sequence is 47.3 mol%. The major cellular fatty acids of strain KGMB03357T are C16:0, C18:0, C18∶1 cis 9, and anteiso-C15∶0. Strain KGMB03357T contains meso-diaminopimelic acid as the diagnostic amino acid in the cell wall peptidoglycan. Based on the phenotypic, phylogenetic, and genomic properties, strain KGMB 03357T represents a novel species of the genus Anaerotignum, for which the name Anaerotignum faecicola sp. nov. is proposed. The type strain is KGMB03357T (= KCTC 15736T = DSM 107953T).


Asunto(s)
Clostridiales/clasificación , Clostridiales/aislamiento & purificación , Heces/microbiología , Microbiota , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , Clostridiales/genética , Clostridiales/fisiología , ADN Bacteriano/genética , Ácido Diaminopimélico/análisis , Ácidos Grasos/análisis , Humanos , Concentración de Iones de Hidrógeno , Peptidoglicano/análisis , ARN Ribosómico 16S/genética , Seúl , Análisis de Secuencia de ADN , Temperatura Ambiental
18.
J Microbiol ; 57(12): 1105-1114, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31686391

RESUMEN

In order to adapt to different environments, Vibrio parahaemolyticus employed a complicated quorum sensing system to orchestrate gene expression and diverse colony morphology patterns. In this study, the function of the putative quorum sensing signal synthase gene cqsA (VPA0711 in V. Parahaemolyticus strain RIMD2210633 genome) was investigated. The cloning and expression of V. parahaemolyticus cqsA in Escherichia coli system induced the production of a new quorum sensing signal that was found in its culture supernatant. The signal was purified by high performance liquid chromatography methods and determined to be 3-hydroxyundecan- 4-one by indirect and direct mass spectra assays. The deletion of cqsA in RIMD2210633 changed V. parahaemolyticus colony morphology from the classical 'fried-egg' shape (thick and opaque in the center, while thin and translucent in the edge) of the wild-type colony to a 'pancake' shape (no significant difference between the centre and the edge) of the cqsA deleted colony. This morphological change could be restored by complementary experiment with cqsA gene or the signal extract. In addition, the expression of opaR, a well-known quorum sensing regulatory gene, could be up-regulated by cqsA deletion. Our results suggested that V. parahaemolyticus used cqsA to produce 3-hydroxyundecan-4-one signal and thereby regulated colony morphology and other quorum sensing-associated behaviors.


Asunto(s)
Proteínas Bacterianas/metabolismo , Percepción de Quorum , Transducción de Señal , Vibrio parahaemolyticus/metabolismo , Proteínas Bacterianas/genética , Clonación Molecular , ADN Bacteriano/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos/genética , Fenotipo , Factores de Transcripción/metabolismo , Vibrio/genética , Vibrio/crecimiento & desarrollo , Vibrio/metabolismo , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/crecimiento & desarrollo
19.
Int J Syst Evol Microbiol ; 69(12): 3702-3709, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31671048

RESUMEN

Strain YZ-8T, isolated from soil sampled at Fildes Peninsula, Antarctica, was found to be a Gram-stain-negative, yellow-pigmented, oxidase- and catalase-positive, non-motile, non-spore-forming, rod-shaped and aerobic bacterium. Strain YZ-8T grewoptimally at pH 7.0 and 20 °C. Tolerance to NaCl was up to 0.3 % (w/v) with optimum growth in the absence of NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YZ-8T belonged to the family Sphingomonas. Strain YZ-8T showed the highest sequence similarities to Sphingomonas molluscorum KMM 3882T (94.4 %), Sphingomonas oligophenolica JCM 12082T (94.4 %), Sphingomonas gotjawalisoli SN6-9T (94.3 %) and Sphingomonas aquatica W1-2-1T (94.3 %). The predominant respiratory isoprenoid quinone and polyamine components were identified as ubiquinone Q-10 and sym-homospermidine, respectively. In addition, carotenoid were also found. The polar lipid profile of the strain YZ-8T was found to contain one phosphatidylethanolamine, an unidentified phospholipid, one diphosphatidylglycerol, one phosphatidylglycerol, two sphingophosphonolipids, one phosphatidylcholine and two unidentified alkali-stable lipids. The G+C content of the genomic DNA was determined to be 58.8 mol%. The main fatty acids were summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c; 35.4 %), summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c; 32.6 %) and C14 : 0 2-OH (7.7 %). On the basis of the evidence presented in this study, a novel species of the genus Sphingomonas, Sphingomonaspaeninsulae sp. nov., is proposed, with the type strain YZ-8T (=CCTCC AB 2017137T=LMG 31027T).


Asunto(s)
Filogenia , Microbiología del Suelo , Sphingomonas/clasificación , Regiones Antárticas , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Espermidina/análogos & derivados , Espermidina/química , Sphingomonas/aislamiento & purificación , Ubiquinona/análogos & derivados , Ubiquinona/química
20.
Int J Syst Evol Microbiol ; 69(12): 3910-3916, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31693472

RESUMEN

A Gram-stain-negative, aerobic, motile, rod-shaped bacterium, designated strain LAM9072T, was isolated from a sample of a sulfonylurea herbicide-degrading consortium enriched with saline soil. The optimal temperature and pH for the growth of strain LAM9072T were 35 °C and 7.0, respectively. Strain LAM9072T could grow in the presence of NaCl up to 9 % (w/v). Comparative analysis of the 16S rRNA gene sequences revealed that strain LAM9072T was closely related to members of the family Vibrionaceae, with the highest similarities to Photobacterium halotolerans MACL01T (97.7 %) and Photobacterium galatheae S2753T (97.7 %). Strain LAM9072T formed a distinct phylogenetic subclade within the genus Photobacterium in the 16S rRNA gene phylogenetic trees. The results of multi-locus sequence analysis revealed a distinct lineage with P. halotolerans MACL01T as its closest relative. The genomic G+C content was 50.2 mol%. The DNA-DNA hybridization values between strain LAM9072T and P. halotolerans LMG 22194T and P. galatheae LMG 28894T were 41.6 and 22.2 %, respectively. The average nucleotide identity values were 90.9 and 78.8 %, respectively, by comparing the draft genome sequences of strain LAM9072T and P. halotolerans LMG 22194T and P. galatheae LMG 28894T. The major fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). Ubiquinone 8 was detected as the predominant respiratory quinone. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, aminophospholipid and four unidentified lipids. Based on its phenotypic characteristics and the results of genotypic analyses, we propose that strain LAM9072T represents a novel species, for which the name Photobacteriumsalinisoli sp. nov. is proposed. The type strain is LAM9072T (=ACCC 19961T=JCM 30852T).


Asunto(s)
Herbicidas/metabolismo , Photobacterium/clasificación , Filogenia , Microbiología del Suelo , Compuestos de Sulfonilurea/metabolismo , Técnicas de Tipificación Bacteriana , Composición de Base , Biodegradación Ambiental , China , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , Photobacterium/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
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