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1.
J Med Entomol ; 59(2): 752-757, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-34971369

RESUMO

Lyme disease, caused by Borrelia burgdorferi sensu stricto and most commonly transmitted by Ixodes scapularis Say (Ixodida: Ixodidae), is the most common tick-borne disease in Maryland. Because B. burgdorferi s.s. is maintained in enzootic cycles among wild mice (Peromyscus spp) and Ixodes spp ticks, differing patterns of parasitism of ticks on mice could impact the infection prevalence with B. burgdorferi. We determined the infection prevalence of Peromyscus spp as well as questing and partially engorged nymphal ticks collected at six sites on private land in five counties in Maryland from May to August 2020. Questing nymph infection prevalence (NIP) was 14%. We trapped 1258 mice and collected 554 ticks and 413 ear tissue samples. The prevalence of infested Peromyscus spp varied based on host age and sex, with older and male mice more likely to be infested. We detected a significant difference amongst the proportion of attached Ixodes and the location of trapping. Similarly, the prevalence of B. burgdorferi infected Peromyscus spp mice varied between locations (average mouse infection prevalence was 40%), with the highest prevalence in locations where Ixodes were the most commonly found ticks. The B. burgdorferi infection prevalence in partially engorged I. scapularis nymphs retrieved from Peromyscus spp was ~36% which lends further support to the host infection prevalence. Local differences in distribution of infected vectors and reservoirs are important factors to consider when planning interventions to reduce Lyme disease risk.


Assuntos
Borrelia burgdorferi , Ixodes , Doença de Lyme , Doenças dos Roedores , Spirochaetaceae , Animais , Doença de Lyme/epidemiologia , Masculino , Maryland/epidemiologia , Ninfa , Peromyscus , Prevalência , Doenças dos Roedores/epidemiologia
2.
Sci Rep ; 11(1): 1421, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446825

RESUMO

Gut microbiota composition can modulate neuroendocrine function, inflammation, and cellular and immunological responses against different pathogens, including viruses. Zika virus (ZIKV) can infect adult immunocompetent individuals and trigger brain damage and antiviral responses. However, it is not known whether ZIKV infection could impact the gut microbiome from adult immunocompetent mice. Here, we investigated modifications induced by ZIKV infection in the gut microbiome of immunocompetent C57BL/6J mice. Adult C57BL/6J mice were infected with ZIKV and the gut microbiota composition was analyzed by next-generation sequencing of the V4 hypervariable region present in the bacterial 16S rDNA gene. Our data showed that ZIKV infection triggered a significant decrease in the bacteria belonging to Actinobacteria and Firmicutes phyla, and increased Deferribacteres and Spirochaetes phyla components compared to uninfected mice. Interestingly, ZIKV infection triggered a significant increase in the abundance of bacteria from the Spirochaetaceae family in the gut microbiota. Lastly, we demonstrated that modulation of microbiota induced by ZIKV infection may lead to intestinal epithelium damage and intense leukocyte recruitment to the intestinal mucosa. Taken together, our data demonstrate that ZIKV infection can impact the gut microbiota composition and colon tissue homeostasis in adult immunocompetent mice.


Assuntos
Firmicutes , Microbioma Gastrointestinal , Mucosa Intestinal , Spirochaetaceae , Infecção por Zika virus , Zika virus/metabolismo , Animais , Firmicutes/classificação , Firmicutes/crescimento & desenvolvimento , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/virologia , Camundongos , Spirochaetaceae/classificação , Spirochaetaceae/crescimento & desenvolvimento , Infecção por Zika virus/metabolismo , Infecção por Zika virus/microbiologia
3.
Int J Syst Evol Microbiol ; 70(12): 6373-6380, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33125316

RESUMO

A novel obligately anaerobic spirochete strain K2T was isolated from bottom marine sediments at Crater Bay of Yankicha Island (Kuril Islands, Russia). Strain K2T had helical shape and Gram-negatively stained. The optimal growth conditions were as follows: the optimum temperature was 28-30 °C with range 5-34 °C; optimal pH at 7.0-7.5 with range of 6.8-8.5; NaCl optimum at 3-3.5 % (w/v) and range of 1-7 % (w/v). Strain K2T was catalase- and oxidase-negative. Glucose fermentation products were acetate, lactate, ethanol, CO2, H2. The major fatty acids were C14 : 0, iso-C13 : 0, iso-C15:0, C14 : 0 DMA, iso-C15 : 0 DMA. The G+C content of genomic DNA was 43.2 mol%. Phylogenetic analyses of 16S rRNA genes showed that strain K2T belonged to the genus Oceanispirochaeta of the family Spirochaetaceae. The 16S rRNA gene sequence similarity of strain K2T and O. litoralis DSM 2029T and O. sediminicola DSM 104770T was 96 and 94 %, respectively. Based on the results of our study, we propose the name Oceanispirochaeta crateris sp. nov.; type strain K2T (=DSM 16308T=VKM B-3266T). Also, the taxonomic status of Spirochaeta perfilevii was revised: 16S rRNA genes sequence showed less than 89 % similarity to nearest phylogenetic neighbours. Therefore, we proposed to separate this species into a novel genus Thiospirochaeta - T. perfilievii gen. nov., comb. nov.


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA , Spirochaeta/classificação , Spirochaetaceae/isolamento & purificação
4.
Int J Syst Evol Microbiol ; 70(8): 4748-4759, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32697184

RESUMO

Anaerobic, fermentative, halotolerant bacteria, strains 4-11T and 585, were isolated from production water of two low-temperature petroleum reservoirs (Russia) and were characterized by using a polyphasic approach. Cells of the strains were spherical, non-motile and 0.30-2.5 µm in diameter. Strain 4-11T grew optimally at 35 °C, pH 6.0 and 1.0-2.0% (w/v) NaCl. Both strains grew chemoorganotrophically with mono-, di- and trisaccharides. The major cellular fatty acids of both strains were C14:0, C16:0, C16:1 ω9 and C18:0 3-OH. Major polar lipids were glycolipids and phospholipids. The 16S rRNA gene sequences of the strains 4-11T and 585 had 99.9% similarity and were most closely related to the sequence of Sphaerochaeta associata GLS2T (96.9, and 97.0% similarity, respectively). The G+C content of the genomic DNA of strains 4-11T and 585 were 46.8 and 46.9%, respectively. The average nucleotide identity and digital DNA-DNA hybridization values between the genomes of strain 4-11T and S. associata GLS2T were 73.0 and 16.9%, respectively. Results of phylogenomic metrics analysis of the genomes and 120 core proteins of strains 4-11T and 585 and their physiological and biochemical characteristics confirmed that the strains represented a novel species of the genus Sphaerochaeta, for which the name Sphaerochaeta halotolerans sp. nov. is proposed, with the type strain 4-11T (=VKM B-3269T=KCTC 15833T). Based on the results of phylogenetic analysis, Sphaerochaeta coccoides was reclassified as member of a new genus Parasphaerochaeta gen. nov., Parasphaerochaeta coccoides comb. nov. The genera Sphaerochaeta and Parasphaerochaeta form a separate clade, for which a novel family, Sphaerochaetaceae fam. nov., is proposed.


Assuntos
Campos de Petróleo e Gás/microbiologia , Filogenia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA , Spirochaetaceae/isolamento & purificação
5.
Int J Syst Evol Microbiol ; 70(8): 4739-4747, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32730198

RESUMO

A novel, obligately anaerobic bacterium (strain SURF-ANA1T) was isolated from deep continental subsurface fluids at a depth of 1500 m below surface in the former Homestake Gold Mine (now Sanford Underground Research Facility, in Lead, South Dakota, USA). Cells of strain SURF-ANA1T were Gram-negative, helical, non-spore-forming and were 0.25-0.55×5.0-75.0 µm with a wavelength of 0.5-0.62 µm. Strain SURF-ANA1T grew at 15-50 °C (optimally at 40 °C), at pH 4.8-9.0 (pH 7.2) and in 1.0-40.0 g l-1 NaCl (10 g l-1 NaCl). The strain grew chemoheterotrophically with hydrogen or mono-, di- and polysaccharides as electron donors. The major cellular fatty acids in order of decreasing abundance (comprising >5% of total) were 10-methyl C16:0, iso-C15:0, C18:2 and C18:0 dimethyl acetal (DMA) and C20:0 methylene-nonadecanoic acid. Phylogenetic analysis based on the 16S rRNA gene sequence of strain SURF-ANA1T indicated a closest relationship with the recently characterized Rectinema cohabitans (99%). Despite high sequence identity, because of its distinct physiology, morphology and fatty acid profile, strain SURF-ANA1T is considered to represent a novel species within the genus Rectinema, for which the name Rectinema subterraneum sp. nov. is proposed. To our knowledge, this is the first report of an isolate within the phylum Spirochaetes from the deep (>100 m) terrestrial subsurface. The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene and genomic sequences of strain SURF-ANA1T are KU359248 and GCF 009768935.1, respectively. The type strain of Rectinema subterraneum is SURF-ANA1T (=ATCC TSD-67=JCM 32656).


Assuntos
Água Subterrânea/microbiologia , Filogenia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , South Dakota , Spirochaetaceae/isolamento & purificação
6.
Clin Chim Acta ; 507: 117-124, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32272157

RESUMO

Leptospira interrogans, Borrelia burgdorferi, and Treponema pallidum are important pathogenic spirochetes. The incidence of human diseases caused by pathogenic spirochetes, e.g., leptospirosis, Lyme disease, and syphilis, has been recently increased, posing a threat to public health. Mechanisms of spirochete pathogenicity are not yet fully understood, and no safe and effective vaccine to prevent and control the infection by pathogenic spirochetes is currently available. In this article, we review the progress of research into the pathogenic spirochete vaccine, mainly in terms of vaccine types. The development of relevant vaccines against pathogenic spirochetes has generally proceeded via several stages, such as the whole-cell inactivated vaccine, live attenuated vaccine, and gene-engineered vaccine, and will likely enter a new stage with the application of gene editing technology. In this review, we mainly summarized the types of pathogenic spirochete vaccines and conducted a preliminary analysis on the protective effect of immunity, and proposed a further prospect for the development of pathogenic spirochete vaccines.


Assuntos
Vacinas Bacterianas , Spirochaetaceae/imunologia , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Engenharia Genética , Vacinas Atenuadas/imunologia
7.
ACS Synth Biol ; 8(9): 2174-2185, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31461261

RESUMO

Consortium-based approaches are a promising avenue toward efficient bioprocessing. However, many complex microbial interactions dictate community dynamics and stability that must be replicated in synthetic systems. The rumen and/or hindguts of large mammalian herbivores harbor complex communities of biomass-degrading fungi and bacteria, as well as archaea and protozoa that work collectively to degrade lignocellulose, yet the microbial interactions responsible for stability, resilience, and activity of the community remain largely uncharacterized. In this work, we demonstrate a "top-down" enrichment-based methodology for selecting a minimal but effective lignocellulose-degrading community that produces methane-rich fermentation gas (biogas). The resulting enrichment consortium produced 0.75-1.9-fold more fermentation gas at 1.4-2.1 times the rate compared to a monoculture of fungi from the enrichment. Metagenomic sequencing of the top-down enriched consortium revealed genomes encoding for functional compartmentalization of the community, spread across an anaerobic fungus (Piromyces), a bacterium (Sphaerochaeta), and two methanogenic archaea (Methanosphaera and Methanocorpusculum). Guided by the composition of the top-down enrichment, several synthetic cocultures were formed from the "bottom-up" using previously isolated fungi, Neocallimastix californiae and Anaeromyces robustus paired with the methanogen Methanobacterium bryantii. While cross-feeding occurred in synthetic co-cultures, removal of fungal metabolites by methanogens did not increase the rate of gas production or the rate of substrate deconstruction by the synthetic community relative to fungal monocultures. Metabolomic characterization verified that syntrophy was established within synthetic co-cultures, which generated methane at similar concentrations compared to the enriched consortium but lacked the temporal stability (resilience) seen in the native system. Taken together, deciphering the membership and metabolic potential of an enriched gut consortium enables the design of methanogenic synthetic co-cultures. However, differences in the growth rate and stability of enriched versus synthetic consortia underscore the difficulties in mimicking naturally occurring syntrophy in synthetic systems.


Assuntos
Biomassa , Methanobacteriaceae/metabolismo , Piromyces/metabolismo , Spirochaetaceae/metabolismo , Anaerobiose , Biocombustíveis , Lignina/metabolismo , Metano/metabolismo , Methanobacteriaceae/crescimento & desenvolvimento , Consórcios Microbianos , Piromyces/crescimento & desenvolvimento , Spirochaetaceae/crescimento & desenvolvimento
8.
Med Vet Entomol ; 33(3): 427-430, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30730054

RESUMO

Ixodes ricinus, comprising the predominant tick species in Europe, can transmit important human pathogens, including Borreliella spp., the causal agent of Lyme borreliosis. One hundred and seventy five roe deer hunted in two areas (plateau and mountain) of Galicia (northwest Spain) were examined for the presence of ticks; all roe deer were infested by I. ricinus. Nymphs (n = 1000), males (n = 1449) and females (n = 1000) of I. ricinus were analysed in pools of up to 10 ticks to detect both Borreliella and Borrelia DNA. The average number of I. ricinus per roe deer was similar in both areas, regardless of the life stage; although the percentage of Borreliella and Borrelia positive pools was higher in ticks collected from roe deer hunted in the plateau area, no significant differences were detected. Sequence analysis at the flagellin gene allowed the identification of four Borreliella species (Borreliella afzelii, Borreliella garinii, Borreliella lusitaniae and Borreliella valaisiana) and Borrelia miyamotoi in adult males; only B. valaisiana and B. miyamotoi were detected in nymphs and all females were negative. All Borreliella and Borrelia species found in roe deer were previously identified in questing I. ricinus collected in the same study area, although the prevalence was lower in the present study. The analysis of male I. ricinus ticks collected from roe deer gives a good estimation of Borreliella diversity in questing ticks.


Assuntos
Cervos/parasitologia , Ixodes/microbiologia , Spirochaetaceae/isolamento & purificação , Animais , Borrelia/isolamento & purificação , Feminino , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Ixodes/crescimento & desenvolvimento , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Espanha
9.
Int J Syst Evol Microbiol ; 68(12): 3747-3753, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30307390

RESUMO

A novel anaerobic fermentative bacterium, strain SEBR 4209T, was isolated from a water sample of a Congolese oil field. Strain SEBR 4209T is phylogenetically related to the genus Pleomorphochaeta, in the family Spirochaetaceae. Its closest relatives are Pleomorphochaeta caudata SEBR 4223T (94.5 % 16S rRNA gene sequence similarity) and Pleomorphochaeta multiformis MO-SPC2T (94.3 % similarity). Like the other members of this genus, cells have a pleomorphic morphology, in particular an annular shape and long stalks. Optimal growth was observed at 37 °C, at pH between 6.8 and 7.0, and with 40 g l-1 NaCl. This strain was only able to grow by fermentation of carbohydrates. The fermentation products from glucose utilization were acetate, ethanol, CO2 and H2. Predominant fatty acids were C14 : 0, C14 : 0 DMA, C16 : 0 and C16 : 1ω7c. The major polar lipids were phosphoglycolipids, phospholipids and glycolipids. The G+C content of the DNA was 29.6 mol%. Based on phenotypic characteristics and phylogenetic traits, strain SEBR 4209T is considered to represent a novel species of the genus Pleomorphochaeta, for which the name Pleomorphochaetanaphthae sp. nov. is proposed. The type strain is SEBR 4209T (=DSM 104684T=JCM 31871T).


Assuntos
Campos de Petróleo e Gás/microbiologia , Filogenia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Congo , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Spirochaetaceae/genética , Spirochaetaceae/isolamento & purificação
10.
Artigo em Inglês | MEDLINE | ID: mdl-29670860

RESUMO

Relapsing fever still remains a neglected disease and little is known on its reservoir, tick vector and physiopathology in the vertebrate host. The disease occurs in temperate as well as tropical countries. Relapsing fever borreliae are spirochaetes, members of the Borreliaceae family which also contain Lyme disease spirochaetes. They are mainly transmitted by Ornithodoros soft ticks, but some species are vectored by ixodid ticks. Traditionally a Borrelia species is associated with a specific vector in a particular geographical area. However, new species are regularly described, and taxonomical uncertainties deserve further investigations to better understand Borrelia vector/host adaptation. The medical importance of Borrelia miyamotoi, transmitted by Ixodes spp., has recently spawned new interest in this bacterial group. In this review, recent data on tick-host-pathogen interactions for tick-borne relapsing fevers is presented, with special focus on B. miyamotoi.


Assuntos
Doenças Negligenciadas/microbiologia , Febre Recorrente/microbiologia , Spirochaetaceae/fisiologia , Doenças Transmitidas por Carrapatos/microbiologia , Animais , Humanos , Ixodes/microbiologia , Ixodes/fisiologia , Spirochaetaceae/genética , Doenças Transmitidas por Carrapatos/transmissão
11.
Int J Syst Evol Microbiol ; 67(9): 3403-3409, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28875893

RESUMO

An obligately anaerobic spirochaete (strain SY2T) was isolated from coastal marine sediments of Tongyeong-Si, South Korea. Strain SY2T was helical-shaped and Gram-stain-negative. Strain SY2T was able to grow at 10-40 °C (optima, 25-30 °C), pH 6.3-8.8 (optima, pH 7.0-8.0) and with 1-7 % (optimum, 2-3 %) NaCl concentration. Strain SY2T was negative for catalase and oxidase activity. The major end-products of glucose fermentation were acetate, ethanol, hydrogen and carbon dioxide. C14 : 0, C16 : 0, iso-C15 : 0, iso-C14 : 0 3-OH, iso-C15 : 1 H/C13 : 0 3-OH and iso-C17 : 1ω9c were predominant fatty acids (>5 %) with minor amounts (<5 %) of C18 : 0, iso-C13 : 0, iso-C17 : 0, iso-C17 : 1/anteiso-C17 : 1 B and C16 : 1ω6c/C16 : 1ω7c. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were major polar lipids. The genomic DNA G+C content was 53.5 mol%. 16S rRNA gene sequence comparisons indicated that strain SY2T represents a member of the family Spirochaetaceae in the phylum Spirochaetes. Strain SY2T has a sequence similarity of 95.1 % with Spirochaeta litoralis R1T and <90.1 % with other members of the genus Spirochaeta. Distinct morphological, physiological and genotypic differences from the previously described taxa support the classification of strain SY2T as a representative of a novel genus and species in the family Spirochaetaceae, for which the name Oceanispirochaeta sediminicola gen. nov., sp. nov. is proposed. The type strain is SY2T (=KEMB 3001-381T=DSM 104770T=KCTC 15593T). Reclassification of Spirochaeta litoralis as Oceanispirochaeta litoralis comb. nov. is also proposed based on polyphasic taxonomic analyses.


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfatidiletanolaminas/química , Fosfatidilgliceróis/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Spirochaetaceae/genética , Spirochaetaceae/isolamento & purificação
12.
Int J Syst Evol Microbiol ; 67(10): 3929-3936, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28895523

RESUMO

Metagenome analysis of coastal marine habitats of Gujarat, India indicated the presence of twelve novel putative lineages of spirochaetes. Out of which a strain designated JC444T representing a novel putative lineage seven was isolated and characterized based on a polyphasic taxonomic approach. Strain JC444T was helical, Gram-stain-negative, obligate anaerobe, catalase and oxidase negative. Strain JC444T was able to grow at 15-45 °C (optimum at 30-35 °C), pH 6.5-8.6 (optimum at 7.5-8.0) and 0.6-5 % (optimum at 1.5-2.0 %) of NaCl concentration. The major end products of glucose fermentation were acetate, formate, hydrogen and carbon dioxide. C14 : 0, iso-C15 : 0, C16 : 0, C18 : 0, iso-C15 : 1H/C13 : 03OH (summed feature 1), iso-C13 : 0, anteiso-C15 : 0 and iso-C17 : 0 were present as fatty acids. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified lipids (L1-4) were the polar lipids. G+C mol% of strain JC444T was 53.6 %. 16S rRNA gene sequence comparisons indicated that strain JC444T represents a member of the family Spirochaetaceae in the order Spirochaetales. Strain JC444T has a sequence similarity of 97.1 % with 'Candidatus Marispirochaeta associata' JC231 and <90.1 % with other members of the family Spirochaetaceae. Distinct morphological, physiological and genotypic differences from the previously described taxa support the classification of strain JC444T as a representative of a new genus and species in the family Spirochaetaceae, for which the name Marispirochaeta aestuarii gen. nov., sp. nov. is proposed. Type strain is JC444T (=KCTC 15554T=DSM 103365T).


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Índia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Spirochaetaceae/genética , Spirochaetaceae/isolamento & purificação
13.
FEMS Microbiol Ecol ; 93(5)2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28175253

RESUMO

Bacteria associated with marine invertebrates are thought to have a range of important roles that benefit the host including production of compounds that may exclude pathogenic microorganisms and recycling of essential nutrients. This study characterised the microbiome of a gonochoric octocoral, Lobophytum pauciflorum, and investigated whether either sex or environmental stresses influenced the diversity of the associated microbiome through amplicon profiling of the bacterial 16S rRNA gene. Sequences affiliated to Spirochaetaceae and Endozoicimonaceae dominated the microbiome of L. pauciflorum, representing 43% and 21% of the community, respectively. Among the dominant class affiliations, no sex-specific differences were detected, though unassigned sequences were at a 2-fold higher relative abundance in samples from female individuals than from males. These potentially novel sequences contributed to observed differences between sexes as detected by a multivariate analysis at the OTU level. Exposing L. pauciflorum fragments to increased temperature (31°C), decreased pH (7.9) or both stressors simultaneously for 12 days did not significantly alter the microbial community, indicating that the soft coral microbiome is relatively resilient to short-term environmental stress.


Assuntos
Alphaproteobacteria/isolamento & purificação , Antozoários/microbiologia , Gammaproteobacteria/isolamento & purificação , Microbiota/genética , Spirochaetaceae/isolamento & purificação , Alphaproteobacteria/genética , Animais , Sequência de Bases , DNA Bacteriano/genética , Feminino , Gammaproteobacteria/genética , Temperatura Alta , Masculino , Tipagem Molecular/métodos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Spirochaetaceae/genética
14.
Int J Syst Evol Microbiol ; 67(2): 417-424, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27902274

RESUMO

A strictly anaerobic Gram-stain-negative bacterium, designated strain SEBR 4223T, was isolated from the production water of an offshore Congolese oil field. Cells were non-motile, pleomorphic and had spherical, annular or budding shapes, often exhibiting long stalks. Strain SEBR 4223T grew on a range of carbohydrates, optimally at 37 °C and pH 7, in a medium containing 40 g l-1 NaCl. Predominant fatty acids were C14 : 0, C14 : 0 DMA, C16 : 0 and C16 : 1ω7c and the major polar lipids were phosphoglycolipids, phospholipids, glycolipids and diphosphatidylglycerol. The G+C content of the DNA was 28.7 mol%. Phylogenetic analysis, based on the 16S rRNA gene sequence, showed that strain SEBR 4223T and Sphaerochaeta multiformis MO-SPC2T formed a cluster with similarity to other species of the genus Sphaerochaeta of of less than 86 %. On the basis of the phenotypic characteristics and taxonomic analyses, we propose a novel genus, Pleomorphochaeta gen. nov., to accommodate the novel species Pleomorphochaeta caudata sp. nov., with SEBR 4223T (=DSM 103077T=JCM 31 475T) as the type strain. We also propose the reclassification of Sphaerochaeta multiformis MO SPC2T as Pleomorphochaeta multiformis MO-SPC2T comb. nov., the type strain of this novel genus and emend description of the genus Sphaerochaeta.


Assuntos
Campos de Petróleo e Gás/microbiologia , Filogenia , Água do Mar/microbiologia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Congo , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Spirochaetaceae/genética , Spirochaetaceae/isolamento & purificação
15.
Pathog Dis ; 74(8)2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27852620

RESUMO

The c-di-GMP network of Borrelia burgdorferi, a causative agent of Lyme disease, consists of Rrp1, a diguanylate cyclase/response regulator; Hpk1, a histidine kinase; PdeA and PdeB, c-di-GMP phosphodiesterases; and PlzA, a PilZ domain c-di-GMP receptor. Borrelia hermsii, a causative agent of tick-borne relapsing fever, possesses a putative c-di-GMP regulatory network that is uncharacterized. While B. burgdorferi requires c-di-GMP to survive within ticks, the associated effector mechanisms are poorly defined. Using site-directed mutagenesis, size exclusion chromatography, isothermal titration calorimetry and fluorescence resonance energy transfer, we investigate the interaction of c-di-GMP with the Borrelia PilZ domain-containing Plz proteins: B. burgdorferi PlzA and B. hermsii PlzC. The Plz proteins were determined to be monomeric in their apo and holo forms and to bind c-di-GMP with high affinity with a 1:1 stoichiometry. C-di-GMP binding induced structural rearrangements in PlzA and PlzC. C-di-GMP binding proved to be dependent on positive charge at R145 of the PilZ domain motif, R145xxxR. Comparative sequence analyses led to the identification of Borrelia consensus sequences for the PilZ domain signature motifs. This study provides insight into c-di-GMP:Plz receptor interaction and identifies a possible switch mechanism that may regulate Plz protein effector functions.


Assuntos
Proteínas de Bactérias/metabolismo , GMP Cíclico/análogos & derivados , Doença de Lyme/microbiologia , Febre Recorrente/microbiologia , Spirochaetaceae/metabolismo , Substituição de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Borrelia burgdorferi/genética , Borrelia burgdorferi/metabolismo , GMP Cíclico/metabolismo , Humanos , Mutação , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Spirochaetaceae/genética
16.
Appl Microbiol Biotechnol ; 100(2): 927-37, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26428233

RESUMO

Although anaerobic digestion (AD) is a widely used option to manage waste activated sludge (WAS), there are some drawbacks related to its slow reaction rate and low energy productivity. This study examined an anaerobic WAS digester, augmented with an iron-reducing microbial consortium, relative to changes in microbial community structure and process performance at decreasing hydraulic retention times (HRTs) of 20 to 10 days. The enhanced methanation performance (approximately 40 % increase in methane yield) by the bioaugmentation was sustained until the HRT was decreased to 12.5 days, under Fe(3+)-rich conditions (ferric oxyhydroxide, 20 mM Fe). Enhanced iron-reducing activity was evidenced by the increased Fe(2+) to total Fe ratio maintained above 50 % during the stable operational phases. A further decrease in HRT to 10 days resulted in a significant performance deterioration, along with a drop in the Fe(2+) to total Fe ratio to <35 %, after four turnovers of operation. Prevailing existence of putative iron-reducing bacteria (IRBs) was identified by denaturing gradient gel electrophoresis (DGGE), with Spirochaetaceae- and Thauera-related organisms being dominant members, and clear dominance shifts among them with respect to decrease in HRT were observed. Lowering HRT led to evident shifts in bacterial community structure likely associated with washout of IRBs, leading to decreases in iron respiration activity and AD performance at a lower HRT. The bacterial community structure shifted dynamically over phases, and the community transitions correlated well with the changes in process performance. Overall, the combined biostimulation and bioaugmentation investigated in this study proved effective for enhanced methane recovery from anaerobic WAS digestion, which suggests an interesting potential for high-rate AD.


Assuntos
Bactérias/metabolismo , Reatores Biológicos , Ferro/metabolismo , Consórcios Microbianos/fisiologia , Esgotos/microbiologia , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Eletroforese em Gel de Gradiente Desnaturante , Spirochaetaceae/metabolismo , Eliminação de Resíduos Líquidos , Águas Residuárias/microbiologia
17.
Int J Syst Evol Microbiol ; 65(12): 4315-4322, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26341497

RESUMO

An anaerobic, saccharolytic bacterial strain designated GLS2T was isolated from aggregates of the psychrotolerant archaeon Methanosarcina mazei strain JL01 isolated from arctic permafrost. Bacterial cells were non-motile, spherical, ovoid and annular with diameter 0.2-4 µm. They were chemoorganoheterotrophs using a wide range of mono-, di- and trisaccharides as carbon and energy sources. The novel isolate required yeast extract and vitamins for growth. The bacteria exhibited resistance to a number of ß-lactam antibiotics, rifampicin, streptomycin and vancomycin. Optimum growth was observed between 30 and 34 °C, at pH 6.8-7.5 and with 1-2 g NaCl l- 1. Isolate GLS2T was a strict anaerobe but it tolerated oxygen exposure. On the basis of 16S rRNA gene sequence similarity, strain GLS2T was shown to belong to the genus Sphaerochaeta within the family Spirochaetaceae. Its closest relatives were Sphaerochaeta globosa BuddyT (99.3 % 16S rRNA gene sequence similarity) and Sphaerochaeta pleomorpha GrapesT (95.4 % similarity). The G+C content of DNA was 47.2 mol%. The level of DNA-DNA hybridization between strains GLS2T and BuddyT was 34.7 ± 8.8 %. Major polar lipids were phosphoglycolipids, phospholipids and glycolipids; major fatty acids were C14 : 0, C16 : 0, C16 : 0 3-OH, C16 : 0 dimethyl acetal (DMA), C16 : 1n8 and C16 : 1 DMA; respiratory quinones were not detected. The results of DNA-DNA hybridization, physiological and biochemical tests demonstrated genotypic and phenotypic differentiation of strain GLS2T from the four species of the genus Sphaerochaeta with validly published names that allowed its separation into a new lineage at the species level. Strain GLS2T therefore represents a novel species, for which the name Sphaerochaeta associata sp. nov. is proposed, with the type strain GLS2T ( = DSM 26261T = VKM B-2742T).


Assuntos
Methanosarcina , Pergelissolo/microbiologia , Filogenia , Spirochaetaceae/classificação , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Spirochaetaceae/genética , Spirochaetaceae/isolamento & purificação
18.
Int J Syst Evol Microbiol ; 64(Pt 12): 4147-4154, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25249566

RESUMO

An anaerobic, psychrophilic bacterium, strain MO-SPC2(T), was isolated from a methanogenic microbial community in a continuous-flow bioreactor that was established from subseafloor sediments collected from off the Shimokita Peninsula of Japan in the north-western Pacific Ocean. Cells were pleomorphic: spherical, annular, curved rod, helical and coccoid cell morphologies were observed. Motility only occurred in helical cells. Strain MO-SPC2(T) grew at 0-17 °C (optimally at 9 °C), at pH 6.0-8.0 (optimally at pH 6.8-7.2) and in 20-40 g NaCl l(-1) (optimally at 20-30 NaCl l(-1)). The strain grew chemo-organotrophically with mono-, di- and polysaccharides. The major end products of glucose fermentation were acetate, ethanol, hydrogen and carbon dioxide. The abundant polar lipids of strain MO-SPC2(T) were phosphatidylglycolipids, phospholipids and glycolipids. The major cellular fatty acids were C14 : 0, C16 : 0 and C16 : 1ω9. Isoprenoid quinones were not detected. The G+C content of the DNA was 32.3 mol%. 16S rRNA gene-based phylogenetic analysis showed that strain MO-SPC2(T) was affiliated with the genus Sphaerochaeta within the phylum Spirochaetes, and its closest relatives were Sphaerochaeta pleomorpha Grapes(T) (88.4 % sequence identity), Sphaerochaeta globosa Buddy(T) (86.7 %) and Sphaerochaeta coccoides SPN1(T) (85.4 %). Based on phenotypic characteristics and phylogenetic traits, strain MO-SPC2(T) is considered to represent a novel species of the genus Sphaerochaeta, for which the name Sphaerochaeta multiformis sp. nov. is proposed. The type strain is MO-SPC2(T) ( = JCM 17281(T) = DSM 23952(T)). An emended description of the genus Sphaerochaeta is also proposed.


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Spirochaetaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Japão , Dados de Sequência Molecular , Oceano Pacífico , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Spirochaetaceae/genética , Spirochaetaceae/isolamento & purificação
19.
Microbiol Res ; 169(5-6): 348-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24239193

RESUMO

Growth temperature range, resistance to selective antibiotics, activities of 23 enzymes, protein fingerprints and fatty acids composition of the spirochaetal strain BR91, isolated from the Culex pipiens mosquito, were tested. The spirochaetes were grown in BSK-H Complete liquid medium. The optimal in vitro growth temperature of the strain was 33 °C. Strain BR91 was sensitive to trimethoprim, nalidixic acid, 5-fluorouracil, and tolerated phosphomycin. The strain produced acid and alkaline phosphatase, esterase (C4), esterase-lipase (C8), leucine arylamidase, naphthol-AS-BI-phosphohydrolase and α-fucosidase. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) assay revealed several major proteins in the size range of 13-16 kDa, 22-30 kDa and 37-131 kDa. Fatty acid methyl ester (FAME) analysis showed that C14:0, C16:0, C18:1 ω9c and summed feature 5 (C18:2 ω6,9c and/or C18:0 anteiso) are major fatty acids. This study highlights certain phenotypic differences between strain BR91 and the Lyme disease spirochaete Borrelia burgdorferi, and supports the hypothesis that strain BR91 represents a unique taxonomical entity in a system of spirochaetal species.


Assuntos
Culex/microbiologia , Spirochaetaceae/classificação , Spirochaetaceae/isolamento & purificação , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/análise , Borrelia burgdorferi , Culicidae , Meios de Cultura/química , Enzimas/análise , Ácidos Graxos/análise , Testes de Sensibilidade Microbiana , Spirochaetaceae/química , Spirochaetaceae/fisiologia , Temperatura
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