Search results for "Desulfovibrio"

Carriage of Enterobacteria Producing Extended-Spectrum β-Lactamases and Composition of the Gut Microbiota in an Amerindian Community

2015

ABSTRACT Epidemiological and individual risk factors for colonization by enterobacteria producing extended-spectrum beta-lactamases (E-ESBL) have been studied extensively, but whether such colonization is associated with significant changes in the composition of the rest of the microbiota is still unknown. To address this issue, we assessed in an isolated Amerindian Guianese community whether intestinal carriage of E-ESBL was associated with specificities in gut microbiota using metagenomic and metatranscriptomic approaches. While the richness of taxa of the active microbiota of carriers was similar to that of noncarriers, the taxa were less homogeneous. In addition, species of four genera,…

Psychrotolerant Sulfate-reducing Bacteria from an Oxic Freshwater Sediment Description of Desulfovibrio cuneatus sp. nov. and Desulfovibrio litoralis…

1998

The most abundant culturable sulfate-reducing bacteria were isolated from the littoral sediment of the oligotrophic Lake Stechlin. The strains STL1 and STL4 were obtained from the oxic uppermost layer, while strain STL6 was isolated from the anoxic zone in 20 to 30 mm depth. The isolates showed a striking morphological feature in tapering off at one end of the cell. Physiological characteristics related them to the genus Desulfovibrio. They contained desulfoviridin. H2, formate, pyruvate, lactate, and fumarate were utilized with sulfate, sulfite, thiosulfate, or elemental sulfur as electron acceptors. All isolates were able to reduce oxygen and survived 120 h of aeration. However, aerobic g…

In vitro and in vivo sulfate reduction in the gut contents of the termite Mastotermes darwiniensis and the rose-chafer Pachnoda marginata.

2005

Sulfate-reducing bacteria (SRB) from termites have been assigned to the genus Desulfovibrio. Desulfovibrio intestinalis lives in the gut of the Australian termite Mastotermes darwiniensis. For the first time we were able to enrich and identify a sulfate-reducing bacterium from the gut of the rose-chafer Pachnoda marginata, which showed the highest 16S rDNA sequence identity (93%) to Desulfovibrio intestinalis and Desulfovibrio strain STL1. Compared to Mastotermes darwiniensis (1x10(7) cells of SRB per ml gut contents), sulfate-reducing bacteria occurred in higher numbers in the gut contents of Pachnoda marginata reaching cell titers of up to 2x10(8) cells per ml gut contents. In vitro sulfa…

Start-Up of Chitosan-Assisted Anaerobic Sludge Bed Reactors Treating Light Oxygenated Solvents under Intermittent Operation

2021

Quality of the granular sludge developed during the start-up of anaerobic up-flow sludge bed reactors is of crucial importance to ensure the process feasibility of treating industrial wastewater such as those containing solvents. In this study, the microbial granule formation from suspended-growth biomass was investigated in two chitosan-assisted reactors. These reactors operated mimicking industrial sites working with night closures treating a mixture of ethanol, ethyl acetate, and 1-ethoxy-2-propanol. Each reactor operated under different hydrodynamic regimes typical from UASB (R1: &lt

Isolation of Desulfovibrio intestinalis sp. nov. from the hindgut' of the lower termite Mastotermes darwiniensis.

1999

A Gram-negative, anaerobic sulfate-reducing bacterium was isolated from hindgut contents of the lower termite Mastotermes darwiniensis Froggatt (strain KMS2). Strain KMS2 is motile by a single polar flagellum. The isolate possesses desulfoviridin and catalase activity. The G+C content of its DNA is in the range of 54.5-55.5 mol% (strain KMS2). It respires hydrogen and different low molecular weight organic compounds in the presence of sulfate, thiosulfate, and sulfite, and also oxygen. The isolated strain ferments pyruvate. Fastest growth with a doubling time of 12.5 h was obtained at 37°C and not at 28°C, the temperature at which the termites were grown. The isolate showed a 16S rDNA seque…

Production of methyl mercury in the gut of the Australian termite Mastotermes darwiniensis

2008

Animals are often exposed to or can ingest heavy metals along with their food. Therefore, we tested whether the hindgut microbiota of Mastotermes darwiniensis possesses the capability to form methyl mercury. The termite M. darwiniensis (Isoptera) was fed with saw dust containing different concentrations of inorganic mercury. Methyl mercury was determined by purge-and-trap capillary gas chromatography-atom fluorescence spectrometry (CGC-AFS) using ethyl mercury chloride as the internal standard. Total mercury concentrations were determined in the termite tissue by inductive coupled plasma-isotope dilution mass spectrometry (ICP-IDMS) after microwave-assisted digestion. The obtained results s…

Diversity and Lignocellulolytic Activities of Cultured Microorganisms

2005

Comparison of the intestinal microbiome of italian patients with multiple sclerosis and their household relatives

2021

Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system, caused by a combination of genetic and environmental factors. In recent years, a role in MS pathogenesis was assigned to the gut microbiota. However, different signatures of gut dysbiosis have been shown to depend on environmental factors, like diet and lifestyle. In this study, we compared the gut microbiome in MS patients and their household healthy relatives sharing lifestyle and environmental factors. Faecal metagenomic DNA was extracted and the V3–V4 regions of the conserved bacterial 16S ribosomal RNA gene were amplified and sequenced. While overall bacterial communities were similar, specific …

BIOREMOVAL 0F SULPHATE LAYER FROM A 15TH CENTURY POLYCHROME MARBLE ARTIFACT

2015

This case study shows the application of viable bacterial cells for removing undesired deposits from the surface of a stone polychrome bas-relief, exhibited at the Interdisciplinary Gallery of Sicily Palazzo Abatellis (Palermo). Diagnostic studies carried out during the restoration were aimed at characterizing the technique of execution and understanding the degradation processes. The results of the XRF and FTIR investigations showed that on large areas of the artifact’s surface, stratified deposits with a significant presence of sulfates were present. For bioremoval of the deposits, viable bacterial cells belonging to the species Desulfovibrio vulgaris, were utilized in gelled solution for…

Sulphate-reducing bacteria in paper machine waters and in suction roll perforations

1978

To define some aspects of the biological corrosion sulphate-reducing bacteria were studied in paper machine waters and in plugged perforations of a suction roll. The desulphuricants were most active on passive fiber recipients. Most bacteria found in fiber plugs taken from the perforations of suction rolls belonged to the genus Desulfovibrio. Desulphuricants were found mainly at the outer ends of plugged perforations, where corrosion of the roll metal is most evident.