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1.
Ecotoxicol Environ Saf ; 187: 109854, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678700

RESUMO

Thallium (Tl) is a toxic element, but little is known about microbial communities' response to TI mobilization and sequestration. Here, we characterize the microbial communities and their feedbacks to Tl-pollution in riverbank soils to understand the distribution of microbial metal tolerance. These soils have been affected by pollution sourced from a Tl-rich mineralized area in Lanmuchang, Guizhou, China. In all studied soil samples, Proteobacteria, Acidobacteria, and Actinobacteria were revealed relatively in higher abundance at the phylum level. The results indicated that a number of microbial communities including Gemmatimonadetes, and Actinobacteria were correlated with total Tl, suggesting potential roles of these microbes to Tl tolerance. The patterns of phylogenetic beta-diversity in studied samples showed a high diversity of the microbial community in soils with high Tl concentrations. Sequence analysis of microbial community indicated that most of the environmental parameters in soils were associated with the major phylogenetic groups such as Gemmobacteria, Bryobacteria, Proteobacteria, Actinobacteria, Firmicutes, and Rhodobacteria. Some species of microbes, Nocardioides (genus), Actinomycetales (Order), Ralstonia (phyla) and Sphingomonas (genus) might are tolerant of Tl. These results provide direction to the microbial communities in the presence of elevated Tl concentration in Lanmuchang and shed light on bioremediation of Tl polluted locations.


Assuntos
Actinobacteria/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Proteobactérias/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/toxicidade , Tálio/toxicidade , Actinobacteria/isolamento & purificação , Biodegradação Ambiental , China , Resistência a Medicamentos , Tolerância a Medicamentos , Microbiota/genética , Filogenia , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/metabolismo , Solo/química , Poluentes do Solo/análise , Tálio/análise
2.
Chemosphere ; 238: 124700, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524602

RESUMO

An eight-year field trial was conducted to investigate the effects of four different N fertilization treatments of urea (CO(NH2)2, the control), ammonium sulfate ((NH4)2SO4), ammonium chloride (NH4Cl), and ammonium hydrogen phosphate [(NH4)2HPO4]) on cadmium (Cd) phytotoxicity in rice and soil microbial communities in a Cd-contaminated paddy of southern China. The results demonstrate that the different N treatments exerted different effects: the application of (NH4)2HPO4 and (NH4)2SO4 significantly increased rice grain yield and decreased soil-extractable Cd content when compared with those of the control, while NH4Cl had a converse effect. Expression of genes related to Cd uptake (IRT and NRAPM genes) and transport (HMA genes) by roots may be responsible for Cd phytotoxicity in rice grown in the different N fertilization treatments. Our results further demonstrate that N fertilization had stronger effects on soil bacterial communities than fungal communities. The bacterial and fungal keystone species were identified by phylogenetic molecular ecological network (pMEN) analysis and mainly fell into the categories of Gammaproteobacteria, Acidobacteria and Actinobacteria for the bacterial species and Ascomycota for the fungal species; all of these keystone species were highly enriched in the (NH4)2HPO4 treatment. Soil pH and soil available-Cd content emerged as the major determinants of microbial network connectors. These results could provide effective fertilizing strategies for alleviating Cd phytotoxicity in rice and enhance the understanding of its underlying microbial mechanisms.


Assuntos
Ascomicetos/isolamento & purificação , Bactérias/isolamento & purificação , Cádmio/análise , Cádmio/toxicidade , Oryza/química , Poluentes do Solo/toxicidade , Acidobacteria/isolamento & purificação , Actinobacteria/isolamento & purificação , Cloreto de Amônio/química , Sulfato de Amônio/química , Ascomicetos/metabolismo , Bactérias/metabolismo , China , Grão Comestível/química , Poluição Ambiental/análise , Fertilizantes/análise , Gammaproteobacteria/isolamento & purificação , Microbiota , Oryza/microbiologia , Fosfatos/química , Filogenia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise , Ureia/química
3.
Ann Agric Environ Med ; 26(4): 644-655, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31885240

RESUMO

CASE DESCRIPTION: Five workers (2 males and 3 females) employed in a furniture factory located in eastern Poland developed hypersensitivity pneumonitis (HP) after the pine wood used for furniture production was replaced by birch wood. All of them reported onset of respiratory and general symptoms (cough, shortness of breath, general malaise) after inhalation exposure to birch dust, showed crackles at auscultation, ground-glass attenuations in HRCT examination, and lymphocytosis in the BAL examination. The diagnosis of acute HP was set in 4 persons and the diagnosis of subacute HP in one. IDENTIFICATION OF SPECIFIC ALLERGEN: Samples of birch wood associated with evoking disease symptoms were subjected to microbiological analysis with the conventional and molecular methods. Two bacterial isolates were found to occur in large quantities (of the order 108 CFU/g) in examined samples: Gram-negative bacterium of the species Pantoea agglomerans and a non-filamentous Gram-positive actinobacterium of the species Microbacterium barkeri. In the test for inhibition of leukocyte migration, 4 out of 5 examined patients showed a positive reaction in the presence of P. agglomerans and 2 in the presence of M. barkeri. Only one person showed the presence of precipitins to P. agglomerans and none to M. barkeri. In the inhalation challenge, which is the most relevant allergological test in the HP diagnostics, all patients reacted positively to P. agglomerans and only one to M. barkeri. The results indicate that P. agglomerans developing in birch wood was the main agent causing HP in the workers exposed to the inhalation of dust from this wood, while the etiologic role of M. barkeri is probably secondary. CONCLUSION: The results demonstrate that apart from fungi and filamentous actinobacteria, regarded until recently as causative agents of HP in woodworkers, Gram-negative bacteria and non-filamentous actinobacteria may also elicit disease symptoms in the workers processing wood infected with large amounts of these microorganisms. The results obtained also seem to indicate that cellular-mediated reactions are more significant for causing disease symptoms compared to those that are precipitin-mediated.


Assuntos
Actinobacteria/isolamento & purificação , Poluentes Ocupacionais do Ar/efeitos adversos , Alveolite Alérgica Extrínseca/microbiologia , Betula/microbiologia , Poeira/análise , Exposição por Inalação/efeitos adversos , Pantoea/isolamento & purificação , Actinobacteria/genética , Actinobacteria/fisiologia , Doença Aguda , Adulto , Poluentes Ocupacionais do Ar/análise , Alveolite Alérgica Extrínseca/etiologia , Feminino , Humanos , Exposição por Inalação/análise , Masculino , Pessoa de Meia-Idade , Pantoea/genética , Pantoea/fisiologia , Polônia , Madeira/microbiologia
4.
Int. microbiol ; 22(4): 403-409, dic. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-185058

RESUMO

A biofilm is a community of microorganisms attached to a surface and embedded in a matrix of extracellular polymeric substances. Biofilms confer resistance towards conventional antibiotic treatments; thus, there is an urgent need for newer and more effective antimicrobial agents that can act against these biofilms. Due to this situation, various studies have been done to investigate the anti-biofilm effects of natural products including bioactive compounds extracted from microorganisms such as Actinobacteria. This review provides an insight into the anti-biofilm potential of Actinobacteria against various pathogenic bacteria, which hopefully provides useful information, guidance, and improvements for future antimicrobial studies. Nevertheless, further research on the anti-biofilm mechanisms and compound modifications to produce more potent anti-biofilm effects are required


No disponible


Assuntos
Actinobacteria/isolamento & purificação , Streptomyces/fisiologia , Biofilmes/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Actinobacteria/genética , Actinobacteria/efeitos dos fármacos
5.
Pan Afr Med J ; 33: 329, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31692847

RESUMO

Introduction: This study was carried out to isolate and screen actinomycetes from soil of two salterns in Taza-Morocco, for the production of antimicrobial compounds against a set of target bacteria. Also, it aims to highlight some practices in order to isolates actinomycetes and screen for their ability to produce antibacterial compounds. Methods: Soil samples were analyzed for physical and chemical parameters including pH, electrical conductivity, and salinity. The actinomycetes were isolated on Casein Starch Agar (CSA) medium and purified on International Streptomyces Project 2 (ISP-2) medium. Antimicrobial activity of actinomycete isolates was evaluated by measuring the inhibition zone. These activities were tested against Dickeya solani IP2222, Pectobacterium brasiliensis 13471a, Escherichia coli K12, Proteus mirabilis, Pseudomonas aeruginosa CECT118, Listeria innocua CECT4030, Staphylococcus aureus CECT976, Bacillus subtilis DSM 347 and Candida alibicans, using three different culture media (CSA, Bennett and Mueller Hinton) and at two temperatures of incubation (30°C and 37°C). Results: Physical and chemical analysis of soil samples showed that both sites are alkaline. Also, with regards to salinity, the second site showed to contain high salt concentration compared the first site. The abundance of bacteria isolated on CSA medium from both sites showed correlation with the physical-chemical properties of the sampling soils. Incubation temperature of 30°C resulted in a high number of actinomycetes (18/22) isolates with antimicrobial effect relative to the temperature of 37°C (4/22). Some actinomycetes isolates show antimicrobial effect on only one culture medium, which shows a special nutritional requirement to express their antimicrobial effect. On the other hand, some isolates, they express their antimicrobial effect on the three media at the same time. Additionally, some isolates of actinomycetes inhibit the growth of several microorganisms at once. While others inhibit the growth of only one microorganism tested which reflects a possible specificity of antimicrobial substances. Conclusion: Growth conditions including, media composition, temperature of incubation and the spectrum of test strain tailors the behavior of the antimicrobial screening.


Assuntos
Actinobacteria/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Meios de Cultura , Testes de Sensibilidade Microbiana , Marrocos , Temperatura Ambiente
6.
Int J Syst Evol Microbiol ; 69(12): 3710-3715, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31665101

RESUMO

A pale-yellow bacterial strain, designated S14-144T, was isolated from tundra soil sampled near the Antarctic Peninsula, South Shetland Islands (62° 22' 34″ S, 59° 42' 34″ W). The cells were strictly aerobic, Gram-stain-positive, non-motile and coccoid-shaped. Growth occurred at 4-28 °C, at pH 5.0-9.0 and in the presence of 0-5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain S14-144T formed a lineage within the genus Nakamurella and shared the highest 16S rRNA gene sequence similarity with Nakamurella deserti 12Sc4-1T (96.5 %) and Nakamurella silvestrisS20-107T (96.4 %). The average nucleotide identity value between the genomes of strain 14-144T and the type strain of the species, N. deserti, was 72.0 % . The DNA G+C content of strain S14-144T was 61.6 mol% . The major cellular fatty acids of strain S14-144T were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and C16 : 0. The strain contained MK-8(H4) as the predominant respiratory quinone, phosphatidylethanolamine and diphosphatidylglycerol as the major polar lipids, rhamnose, ribose and glucose as the major whole-cell sugars, and meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. On the basis of the phylogenetic, phenotypic and chemotaxonomic analysis, strain S14-144T is considered to represent a novel species of the genus Nakamurella, for which the name Nakamurella antarctica sp. nov. is proposed. The type strain is S14-144T (=CCTCC AB 2015345T=KCTC 39796T).


Assuntos
Actinobacteria/classificação , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Ilhas , Peptidoglicano/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tundra
7.
World J Microbiol Biotechnol ; 35(10): 153, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31576426

RESUMO

Karst caves, considering to be the "arks" of biodiversity, often contain high levels of endemism. In the present study, the actinobacterial community in Shuanghe Cave, the longest cave in Asia, was analyzed for the first-time using culture-dependent and -independent (16S rRNA amplicon sequencing) approaches. The amplicon sequencing analysis revealed a broad taxonomic diversity in Shuanghe Cave, including 19 phyla (predominantly Actinobacteria) and 264 different genera. While the culture-dependent method got the unrepresentative but supplemental result, a total of 239 actinomycetes were isolated and were identified to seven genera based on culture features and 16S rRNA tests. Among the three habitats (soil, rock soil, and bat guano), the dominant phyla did not differ significantly, while the dominant genus community varied among different habitats, and the richness in soil and rock soil samples was higher than that in bat guano. Furthermore, 16 isolate strains showed antimicrobial activity, especially, the strain S142 (Streptomyces badius) and S761 (Actinoplanes friuliensis) exhibited the most promising activity against various pathogens. Overall, this work showed the abundant bacterial diversity and the antimicrobial potential of the isolates from the Shuanghe Cave.


Assuntos
Actinobacteria/isolamento & purificação , Cavernas/microbiologia , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/crescimento & desenvolvimento , Animais , Ásia , Biodiversidade , Quirópteros/microbiologia , DNA Bacteriano/genética , Ecossistema , Sedimentos Geológicos/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do Solo
8.
Nat Biotechnol ; 37(11): 1314-1321, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31570900

RESUMO

Most microorganisms from all taxonomic levels are uncultured. Single-cell genomes and metagenomes continue to increase the known diversity of Bacteria and Archaea; however, while 'omics can be used to infer physiological or ecological roles for species in a community, most of these hypothetical roles remain unvalidated. Here, we report an approach to capture specific microorganisms from complex communities into pure cultures using genome-informed antibody engineering. We apply our reverse genomics approach to isolate and sequence single cells and to cultivate three different species-level lineages of human oral Saccharibacteria (TM7). Using our pure cultures, we show that all three Saccharibacteria species are epibionts of diverse Actinobacteria. We also isolate and cultivate human oral SR1 bacteria, which are members of a lineage of previously uncultured bacteria. Reverse-genomics-enabled cultivation of microorganisms can be applied to any species from any environment and has the potential to unlock the isolation, cultivation and characterization of species from as-yet-uncultured branches of the microbial tree of life.


Assuntos
Actinobacteria/metabolismo , Anticorpos/metabolismo , Proteínas de Membrana/imunologia , Boca/microbiologia , Análise de Célula Única/métodos , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Genômica , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Modelos Moleculares , Filogenia , Conformação Proteica , Genética Reversa , Análise de Sequência de DNA
9.
Int J Syst Evol Microbiol ; 69(12): 3946-3954, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31535962

RESUMO

Three actinobacterial strains, 27D-LEPIT, 1B-Mac and 36A-HELLB, were isolated from small standing and running freshwater habitats located in Salzburg, Austria. Phylogenetic reconstructions based on 16S rRNA gene sequences and genome based on concatenated amino acid sequences of 119 single-copy genes referred the three strains within the family Microbacteriaceae to the genus Rhodoluna. The strains showed 100 % 16S rRNA gene sequence similarities to the previously described Candidatus Rhodoluna limnophila. Cells were very small, approximately 0.5×0.3 µm, and showed a red pigmentation in liquid nutrient broth-soyotone-yeast extract medium as well as on agar plates. The strains assimilated a broad variety of substrates; however, the patterns differed a great deal between the three investigated strains. For strain 27D-LEPIT, the major fatty acids were iso-C14 : 0 and anteiso-C15 : 0; the identified polar lipids were phosphatidylglycerol and diphosphatidylglycerol; the major respiratory quinone was MK-11; and analysis of the peptidoglycan structure indicated the presence of type B2ß (typeB10). The genomic DNA of the three strains was very small (1.4 Mbp) and had a DNA G+C content of 54 mol%. The investigated traits suggested that strains 36A-HELLB (=DSM 107805=JCM 32927), 1B-Mac (=DSM 107802=JCM 32925) and 27D-LEPIT (=JCM 32926T =DSM 107804T) represent a new species for which the name Rhodolunalimnophila sp. nov. is proposed, with strain 27D-LEPIT as the type strain.


Assuntos
Actinobacteria/classificação , Água Doce/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Áustria , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Tamanho do Genoma , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
10.
Int J Syst Evol Microbiol ; 69(11): 3629-3635, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31511125

RESUMO

Two Gram-stain-positive, irregular rod-shaped (0.2-0.5×1.3-2.5 um) strains, HY056T and HY057, were isolated from the faeces of Equus kiang (the largest of the wild asses) collected at different regions from the Qinghai-Tibetan Plateau of PR China. Phylogenetic analyses indicated that strains HY056T and HY057 belong to the genus Nocardioides by sharing a similarity ranging from 96.3 to 97.0 % in the 16S rRNA gene sequence and forming a distinct cluster with Nocardioides daphniae JCM 16608T, Nocardioides houyundeii 78T, Nocardioides solisilvae Ka25T and Nocardioides gilvus XZ17T. The digital DNA-DNA hybridization value of strain HY056T was 96.9 % with strain HY057, but less than 30.0 % with the above four closest relatives. MK-8(H4) was the predominant (91.6 %) respiratory quinone. The cell wall contained ll-2,6-diaminopimelic acid as the diamino acid of the peptidoglycan. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phospholipid. The predominant fatty acids (>10.0 %) were C18 : 1ω9c and iso-C16:0. The DNA G+C contents of strains HY056T and HY057 were 68.9 and 69.1 mol%, respectively. ß-Glucosidase expression was positive, and acid was produced from d-fructose. Strain HY056T (=CGMCC 4.7563T=JCM 33399T) is assigned as the type strain of a novel species within the genus Nocardioides, for which the name Nocardioidesyefusunii sp. nov is proposed.


Assuntos
Actinobacteria/classificação , Equidae/microbiologia , Fezes/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 69(12): 3792-3799, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31532356

RESUMO

A novel actinobacterium, designated strain CFH 30434T, was isolated from a soil sample collected from a karst cave in Luoyang, Henan Province, PR China. The taxonomic position of the strain was investigated by using a polyphasic approach. Cells of the strain were aerobic, Gram-stain-positive, non-motile and coccoid or short rods. The strain was found to be oxidase-positive and weakly catalase-positive. Strain CFH 30434T grew optimally at 28 °C, pH 7.0-9.0 and in the presence of up to 0-1.5 % NaCl (w/v). The whole-cell sugars were glucose, mannose and rhamnose. The major isoprenoid quinone was MK-9(H8) and the major fatty acids (>10 % of the total fatty acids compositions) were anteiso-C15 : 0, iso-C15:0 and iso-C14 : 0. The polar lipids detected were diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified phosphoglycolipid, an unidentified phospholipid and an unidentified glycolipid. The genomic DNA G+C content was determined to be 72.3 mol%. The results of phylogenetic analysis of 16S rRNA gene sequences indicated that CFH 30434T clustered within the family Promicromonosporaceae, and closely with the type strains of Xylanimicrobium pachnodae DSM 12657T, Myceligenerans crystallogenes DSM 17134T and Promicromonospora xylanilytica CCTCC AA 208046T (97.3 %, 96.2 and 95.9 % sequence similarities, respectively). Phylogenetic analysis showed that strain CFH 30434T formed a separate evolutionary branch, and was parallel to other related genera of Promicromonosporaceae. Its phylogenetic distinctiveness and distinguishing phenotypic characteristics supported that strain CFH 30434T represents a novel genus of the family Promicromonosporaceae, for which the name Antribacter gilvus gen. nov., sp. nov. is proposed. The type strain is CFH 30434T (=CGMCC 1.13856T=KCTC 49093T).


Assuntos
Actinobacteria/classificação , Cavernas/microbiologia , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Actinomycetales/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
Int J Syst Evol Microbiol ; 69(11): 3519-3523, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31483241

RESUMO

A Gram-stain-positive, rod-shaped and motile bacterium with lateral flagellum, designated T3246-1T, was isolated from an ice core, which was drilled from Hariqin Glacier on the Tibetan Plateau, PR China. It grew optimally at 20 °C, pH 7-8 and in the presence of 3 % (w/v) NaCl. The major fatty acid of strain T3246-1T was anteiso-C15 : 0. Major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol. MK-8 was the dominant isoprenoid quinone. The whole-cell sugars were rhamnose, xylose and mannose. The major cell-wall peptidoglycan was lysine. The genomic DNA G+C content of the strain was 71.4 mol%. Results of phylogenetic analysis based on 16S rRNA gene sequences showed that strain T3246-1T formed a lineage within the genus Haloactinobacterium and was closely related to Haloactinobacterium album YIM 93306T with 95.99 % similarity. The average nucleotide identity value between strain T3246-1T and Haloactinobacterium album YIM 93306T was 76.65 %. Based on phenotypic and chemotaxonomic characteristics, strain T3246-1T was considered to represent a novel species of the genus Haloactinobacterium, for which the name Haloactinobacterium glacieicola sp. nov. is proposed. The type strain is T3246-1T (=CGMCC 1.13535T=JCM 32923T).


Assuntos
Actinobacteria/classificação , Camada de Gelo/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
Int. microbiol ; 22(3): 377-390, sept. 2019. mapas, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184845

RESUMO

Easter Island is an isolated volcanic island in the Pacific Ocean. Despite the extended knowledge about its origin, flora, and fauna, little is known about the bacterial diversity inhabiting this territory. Due to its isolation, Easter Island can be considered as a suitable place to evaluate microbial diversity in a geographically isolated context, what could shed light on actinobacterial occurrence, distribution, and potential novelty. In the present study, we performed a comprehensive analysis of marine Actinobacteria diversity of Easter Island by studying a large number of coastal sampling sites, which were inoculated into a broad spectrum of different culture media, where most important variations in composition included carbon and nitrogen substrates, in addition to salinity. The isolates were characterized on the basis of 16S ribosomal RNA gene sequencing and phylogenetic analysis. High actinobacterial diversity was recovered with a total of 163 pure cultures of Actinobacteria representing 72 phylotypes and 20 genera, which were unevenly distributed in different locations of the island and sample sources. The phylogenetic evaluation indicated a high degree of novelty showing that 45% of the isolates might represent new taxa. The most abundant genera in the different samples were Micromonospora, Streptomyces, Salinispora, and Dietzia. Two aspects appear of primary importance in regard to the high degree of novelty and diversity of Actinobacteria found. First, the application of various culture media significantly increased the number of species and genera obtained. Second, the geographical isolation is considered to be of importance regarding the actinobacterial novelty found


No disponible


Assuntos
Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Biodiversidade , Microbiologia Ambiental , Actinobacteria/genética , Técnicas Bacteriológicas , Chile , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Filogenia , Polinésia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
Int J Syst Evol Microbiol ; 69(10): 3041-3048, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31395120

RESUMO

A novel irregularly shaped and slightly curved rod bacterial strain, GLDI4/2T, showing activity of fructose 6-phosphate phosphoketolase was isolated from a faecal sample of an adult gelada baboon (Theropithecus gelada). Phylogenetic analyses based on 16S rRNA genes as well as multilocus sequences (representing fusA, gyrB and xfp genes) and the core genome revealed that GLDI4/2T exhibited phylogenetic relatedness to Alloscardovia omnicolens DSM 21503T and to Alloscardovia macacae DSM 24762T. Comparative analysis of 16S rRNA gene sequences confirmed the phylogenetic results showing the highest gene sequence identity with strain A. omnicolens DSM 21503T (96.0 %). Activities of α- and ß-gluco(galacto)sidases were detected in strain GLDI4/2T, which is characteristic for almost all members of the family Bifidobacteriaceae. Compared to other Alloscardovia species its DNA G+C content (43.8 mol%) was very low. Phylogenetic studies and the evaluation of phenotypic characteristics, including the results of biochemical, physiological and chemotaxonomic analyses, confirmed the novel species status for strain GLDI4/2T, for which the name Alloscardoviatheropitheci sp. nov. is proposed. The type strain is GLDI4/2T (=DSM 106019T=JCM 32430T).


Assuntos
Actinobacteria/classificação , Filogenia , Theropithecus/microbiologia , Actinobacteria/isolamento & purificação , Aldeído Liases , Animais , Animais de Zoológico/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Itália , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Int J Syst Evol Microbiol ; 69(10): 2966-2971, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418670

RESUMO

A novel actinobacterium, designated LHW52908T, was isolated from a marine sponge, Leucettachagosensis, collected in the South China Sea. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain LHW52908T was member of the family Geodermatophilaceae, with highest similarities to Geodermatophilus obscurus DSM 43160T (97.7 %), Geodermatophilus siccatus CF6T (97.6 %) and Geodermatophiluschilensis B12T (97.5 %). Multilocus sequence analysis confirmed that the strain should be a member of genus Geodermatophilus. Chemotaxonomic characteristics confirmed the genus-level affiliation of strain LHW52908T. Based on phylogenetic data, average nucleotide identity and digital DNA-DNA hybridization results, strain LHW52908T could be distinguished from its closest neighbours, representing a novel species of the genus Geodermatophilus, for which the name Geodermatophilusmarinus sp. nov. is proposed, with the type strain LHW52908T (=DSM 106570T=CCTCC AA 2018014T).


Assuntos
Actinobacteria/classificação , Filogenia , Poríferos/microbiologia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Oceanos e Mares , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Int J Syst Evol Microbiol ; 69(11): 3500-3507, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31418680

RESUMO

A novel actinobacterium, designated strain NEAU-THZ27T, was isolated from soil collected from the Cornel peak in Jiaozuo, Henan Province, PR China and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the strain coincided with those of members of the genusKribbella. The results of 16S rRNA gene sequence analysis showed that strain NEAU-THZ27T belongs to the genus Kribbella and was most closely related to Kribbella podocarpi YPL1T (98.96 %), Kribbella karoonensis Q41T (98.89 %), Kribbella aluminosa HKI 0478T (98.86%) and Kribbella hippodromi S1.4T (98.85 %), similarities to other type strains of species of the genus Kribbella were found to be less than 98.7 %. Phylogenetic analyses using the 16S rRNA gene sequence and multilocus sequence analysis using the concatenated gene sequences of the gyrB, rpoB, recA, relA and atpD genes all showed that the strain formed a separate branch in the genus Kribbella. The cell wall contained ll-diaminopimelic acid as the major diamino acid and the whole-cell hydrolysates were ribose and glucose. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. The predominant menaquinone was MK-9(H4). Major fatty acids were iso-C16 : 0, iso-C14 : 0 and anteiso-C15 : 0, these chemotaxonomic data supported the affiliation of strain NEAU-THZ27T to the genus Kribbella. The DNA G+C content was 68.0 mol%. Furthermore, the strain could be clearly distinguished by concatenated gene genetic distances, the combination of DNA-DNA hybridization results and some phenotypic characteristics. Therefore, it is proposed that strain NEAU-THZ27T represents a novel species of the genus Kribbella, for which the name Kribbella jiaozuonensis sp. nov. is proposed. The type strain is NEAU-THZ27T (=CGMCC 4.7504T=DSM 105535T).


Assuntos
Actinobacteria/classificação , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Genes Bacterianos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Int J Syst Evol Microbiol ; 69(11): 3603-3608, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31433288

RESUMO

A novel actinomycete, designated strain GLM-1T, was isolated from arbuscular mycorrhizal fungal spores from Funneliformis mosseae RYA08, collected from Aquilaria crassna Pierre ex Lec. rhizosphere soil in Klaeng, Rayong Province, Thailand. Morphological characteristics of this strain included long chains of rod-like cells and squarish elements. The cell-wall composition of this novel isolate contained meso-diaminopimelic acid. The whole-cell diagnostic sugars were arabinose and galactose. The predominant menaquinone was MK-9(H4). The major fatty acids were iso-C16 : 0 and iso-C15 : 0. Only phosphatidylethanolamine was detected as a polar lipid. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain GLM-1T was closely related to Amycolatopsis rhabdoformis SB026T (99.11 %) with a low DNA-DNA hybridization value of 22.6-34.7 %. Genome sequencing revealed a genome size of 10 Mbp. There were obvious distinctions in the average nucleotide identity values between stain GLM-1T and its closely related strains at around 86-93 % (ANIb) and 89-94 % (ANIm). The digital DNA-DNA hybridization values between strain GLM-1T and type strains of phylogenetically related species were 34-55 %. The G+C content of the genomic DNA was 71.8 mol%. Based on these data, strain GLM-1T is considered to represent a novel species of the genus Amycolatopsis, for which the name Amycolatopsiseburnea sp. nov. is proposed. The type strain is GLM-1T (=TBRC 9315T=NBRC 113658T).


Assuntos
Actinobacteria/classificação , Micorrizas , Filogenia , Microbiologia do Solo , Esporos Fúngicos , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Rizosfera , Análise de Sequência de DNA , Tailândia , Vitamina K 2/análogos & derivados , Vitamina K 2/química
18.
PLoS Negl Trop Dis ; 13(8): e0007056, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31465459

RESUMO

Mycetoma is a devastating neglected tropical disease, caused by various fungal and bacterial pathogens. Correct diagnosis to the species level is mandatory for proper treatment. In endemic areas, various diagnostic tests and techniques are in use to achieve that, and that includes grain culture, surgical biopsy histopathological examination, fine needle aspiration cytological (FNAC) examination and in certain centres molecular diagnosis such as PCR. In this retrospective study, the sensitivity, specificity and diagnostic accuracy of grain culture, surgical biopsy histopathological examination and FNAC to identify the mycetoma causative organisms were determined. The histopathological examination appeared to have better sensitivity and specificity. The histological examination results were correct in 714 (97.5%) out of 750 patients infected with Madurella mycetomatis, in 133 (93.6%) out of 142 patients infected with Streptomyces somaliensis, in 53 (74.6%) out of 71 patients infected with Actinomadura madurae and in 12 (75%) out of 16 patients infected with Actinomadura pelletierii. FNAC results were correct in 604 (80.5%) out of 750 patients with Madurella mycetomatis eumycetoma, in 50 (37.5%) out of 133 Streptomyces somaliensis patients, 43 (60.5%) out of 71 Actinomadura madurae patients and 11 (68.7%) out of 16 Actinomadura pelletierii. The mean time required to obtain the FNAC result was one day, and for the histopathological examinations results it was 3.5 days, and for grain it was a mean of 16 days. In conclusion, histopathological examination and FNAC are more practical techniques for rapid species identification than grain culture in many endemic regions.


Assuntos
Testes Diagnósticos de Rotina/métodos , Micetoma/diagnóstico , Micetoma/microbiologia , Micetoma/patologia , Patologia Molecular/métodos , Actinobacteria/isolamento & purificação , Adolescente , Adulto , Idoso , Biópsia , Criança , Pré-Escolar , Feminino , Humanos , Madurella/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Micetoma/cirurgia , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Sensibilidade e Especificidade , Streptomyces/isolamento & purificação , Adulto Jovem
19.
Rev Soc Bras Med Trop ; 52: e20190081, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31340368

RESUMO

Eggerthella lenta is a gram-positive anaerobic bacillus that has been associated with life-threatening infections. Bacteremia is always clinically significant and is mostly but not always associated with gastrointestinal disease. We present a unique case of abrupt deterioration and rapid development of septic shock secondary to periurethral abscess caused by E. lenta infection. This case highlights the atypical clinical presentation, risk factors, uncommon source of infection, challenges in therapy, and outcome of this infrequent infection. There is still a gap in the understanding of E. lenta pathogenicity, and more literature is needed to establish clear management recommendations.


Assuntos
Abscesso/diagnóstico por imagem , Actinobacteria/isolamento & purificação , Bacteriemia/microbiologia , Doenças Uretrais/diagnóstico por imagem , Abscesso/tratamento farmacológico , Abscesso/microbiologia , Actinobacteria/classificação , Antibacterianos/uso terapêutico , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infecção Pélvica/diagnóstico , Infecção Pélvica/microbiologia , Fatores de Risco , Tomografia Computadorizada por Raios X , Doenças Uretrais/tratamento farmacológico
20.
Int J Syst Evol Microbiol ; 69(10): 3068-3073, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31310199

RESUMO

The taxonomic position of 'Actinomadura roseorufa' LMG 30035T, a semduramicin-producing mutant of strain ATCC 53666P, which was isolated from a soil sample collected in Yamae Village, Kamamoto, Japan, was clarified in the present study using a polyphasic approach. This Gram-positive, aerobic actinomycete formed a well-developed, extensively branched, non-fragmenting substrate and aerial mycelia which differentiated into single, smooth-appearing spores. Based on analysis of nearly complete 16S rRNA gene sequence, strain LMG 30035T was found to be closely related to the type strains of Actinomadura fibrosa ATCC 49459T (98.88 %) and Actinomadura formosensis JCM 7474T (98.82 %) (pairwise similarity values in parentheses). Digital DNA-DNA hybridisation experiments revealed unambiguously that strain LMG 30035T represents a novel Actinomadura species (OrthoANIu values less than 83.1 %; dDDH values less than 27.2 % with type strains of validly named Actinomadura species). Analysis of the cell wall revealed the presence of meso-diaminopimelic acid in the peptidoglycan. The whole-cell sugars were glucose, madurose, galactose, ribose and rhamnose. The major polar lipids included phosphatidylinositol and diphosphatidylglycerol. The predominant menaquinones were MK-9(H6), MK-9(H8), MK-9(H4) and MK-9(H2). The major fatty acids were C16 : 00, 10-methyl C18 : 0, C18 : 1 ω9c and C18 : 00. The DNA G+C content of its genome was 72.5 mol%. In summary, these characteristics distinguish strain LMG 30035T from validly named species of the genus Actinomadura, and therefore, we propose to classify this strain formally as the novel species Actinomadura roseirufa sp. nov. with LMG 30035T (=CECT 9808T,=ATCC 53664T) as the type strain.


Assuntos
Actinobacteria/classificação , Nigericina/análogos & derivados , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Ionóforos , Japão , Nigericina/metabolismo , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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