Publications by authors named "Rijpstra W"
The composition of the core lipids and intact polar lipids (IPLs) of five Rubrobacter species was examined. Methylated (ω-4) fatty acids (FAs) characterized the core lipids of Rubrobacter radiotolerans, R. xylanophilus and R.
View Article and Find Full Text PDFIn acid drainage environments, biosulfidogenesis by sulfate-reducing bacteria (SRB) attenuates the extreme conditions by enabling the precipitation of metals as their sulfides, and the neutralization of acidity through proton consumption. So far, only a handful of moderately acidophilic SRB species have been described, most of which are merely acidotolerant. Here, a novel species within a novel genus of moderately acidophilic SRB is described, gen.
View Article and Find Full Text PDFThe genus comprises sulfur-oxidizing bacteria thriving in soda lakes at high pH and salinity. Depending on the geographical location and the season, these lakes can strongly vary in temperature. To obtain a comprehensive understanding of the molecular and physiological adaptations to low temperature, we compared the responses of two strains to low (10°C) and high (30°C) temperatures.
View Article and Find Full Text PDFPlanctomycetes of the family Gemmataceae are characterized by large genome sizes and cosmopolitan distribution in freshwater and terrestrial environments but their ecological functions remain poorly understood. In this study, we characterized a novel representative of this family, strain PL17, which was isolated from a littoral tundra wetland and was capable of growth on xylan and cellulose. Cells of this isolate were represented by pink-pigmented spheres that multiplied by budding and occurred singly or in short chains and aggregates.
View Article and Find Full Text PDFgen. nov., sp. nov., an aerobic methanotroph isolated from an oil sands tailings pond.
Int J Syst Evol Microbiol
April 2020
An aerobic methane oxidizing bacterium, designated XLMV4, was isolated from the oxic surface layer of an oil sands tailings pond in Alberta, Canada. Strain XLMV4 is capable of growth on methane and methanol as energy sources. NHCl and sodium nitrate are nitrogen sources.
View Article and Find Full Text PDFLacipirellula parvula gen. nov., sp. nov., representing a lineage of planctomycetes widespread in low-oxygen habitats, description of the family Lacipirellulaceae fam. nov. and proposal of the orders Pirellulales ord. nov., Gemmatales ord. nov. and Isosphaerales ord. nov.
Syst Appl Microbiol
January 2020
Pirellula-like planctomycetes are ubiquitous aquatic bacteria, which are often detected in anoxic or micro-oxic habitats. By contrast, the taxonomically described representatives of these bacteria, with very few exceptions, are strict aerobes. Here, we report the isolation and characterization of the facultatively anaerobic planctomycete, strain PX69, which was isolated from a boreal lake.
View Article and Find Full Text PDFThe family accommodates aerobic, chemoorganotrophic planctomycetes, which inhabit various freshwater ecosystems, wetlands and soils. Here, we describe a novel member of this family, strain PX52, which was isolated from a boreal eutrophic lake in Northern Russia. This isolate formed pink-pigmented colonies and was represented by spherical cells that occurred singly, in pairs or aggregates and multiplied by budding.
View Article and Find Full Text PDF" Nitrosotenuis uzonensis" is the only cultured moderately thermophilic member of the thaumarchaeotal order (NP) that contains many mesophilic marine strains. We examined its membrane lipid composition at different growth temperatures (37°C, 46°C, and 50°C). Its lipids were all membrane-spanning glycerol dialkyl glycerol tetraethers (GDGTs), with 0 to 4 cyclopentane moieties.
View Article and Find Full Text PDFThree strains of aerobic psychrotolerant methanotrophic bacteria , isolated from geographically remote low-temperature environments in Northern Russia, were grown at three different growth temperatures, 20, 10 and 4°C and were found to be capable of oxidizing methane at all temperatures. The three strains adapted their membranes to decreasing growth temperature by increasing the percent of unsaturated fatty acid (FAs), both for the bulk and intact polar lipid (IPL)-bound FAs. Furthermore, the ratio of βOH-C to -C increased as growth temperature decreased.
View Article and Find Full Text PDFWe analyzed the polar membrane lipids of 13 strains of halo(alkali)philic euryarchaea from hypersaline lakes. Nine belong to the class , representing two functional groups: aerobic polysaccharide utilizers and sulfur-respiring anaerobes. The other four strains represent halo(alkali)philic methanogens from the class and a recently discovered class .
View Article and Find Full Text PDFAn isolate of strictly aerobic, pale-pink pigmented bacteria, strain AF10, was obtained from an organic soil layer in forested tundra, Nadym region, West Siberia. Cells of strain AF10 were Gram-negative, non-motile rods that produced an amorphous extracellular polysaccharide-like substance and formed large cell aggregates in old cultures. These bacteria were chemoorganotrophic, mildly acidophilic and psychrotolerant, and grew between pH 3.
View Article and Find Full Text PDFMethanogenic enrichments from hypersaline lakes at moderate thermophilic conditions have resulted in the cultivation of an unknown deep lineage of euryarchaeota related to the class Halobacteria. Eleven soda lake isolates and three salt lake enrichment cultures were methyl-reducing methanogens that utilize C1 methylated compounds as electron acceptors and H2 or formate as electron donors, but they were unable to grow on either substrates alone or to form methane from acetate. They are extreme halophiles, growing optimally at 4 M total Na and the first representatives of methanogens employing the 'salt-in' osmoprotective mechanism.
View Article and Find Full Text PDFsp. nov., a member of the family from lichen-dominated forested tundra.
Int J Syst Evol Microbiol
April 2018
An isolate of aerobic, Gram-stain-negative, rod-shaped, non-motile and light-pink pigmented bacteria, designated SBC68, was obtained from slightly decomposed thalli of the lichen sp. collected from the forested tundra of north-western Siberia. Cells of this isolate occurred singly, in pairs or in rosettes.
View Article and Find Full Text PDFA novel member of the phylum was isolated from an oilsands tailings pond in Alberta, Canada. Cells of isolate NVT are Gram-negative, strictly aerobic, non-pigmented, non-motile cocci to diplococci 0.5-1.
View Article and Find Full Text PDFTwo strains of aerobic, budding, pink-pigmented bacteria, P12T and P515, were isolated from a lichen-dominated peatland and a forested tundra soil of north-western Siberia, respectively. Cells of these isolates were represented by non-motile spheres that occurred singly or were arranged in short chains and aggregates. While growing on solid media, cells of strains P12T and P515 attached to the surface by means of holdfast-like appendages.
View Article and Find Full Text PDFHopanoids are pentacyclic triterpenoid lipids synthesized by different bacterial groups. Methylated hopanoids were believed to be exclusively synthesized by cyanobacteria and aerobic methanotrophs until the genes encoding for the methylation at the C-2 and C-3 position (P and R) were found to be widespread in the bacterial domain, invalidating their use as specific biomarkers. These genes have been detected in the genome of the ".
View Article and Find Full Text PDFAn aerobic, mildly acidophilic actinobacterium was isolated from the Ochre Beds bog in Kootenay National Park, Canada. Cells of isolate OB1T were Gram-stain-positive, non-motile, pink- to purple-pigmented filaments. The pH range for growth was pH 3.
View Article and Find Full Text PDFAn aerobic, budding, dark pink to red-pigmented bacterium was isolated from an acidic boreal Sphagnum peat bog and designated strain SP5T. Cells of this strain were non-motile spheres that were uniformly covered with crateriform pits and fimbria, and tended to form aggregates during growth in liquid media. Strain SP5T was capable of growth between pH 4.
View Article and Find Full Text PDFA wide diversity of ammonia-oxidizing archaea (AOA) within the phylum Thaumarchaeota exists and plays a key role in the N cycle in a variety of habitats. In this study, we isolated and characterized an ammonia-oxidizing archaeon, strain MY3, from a coal tar-contaminated sediment. Phylogenetically, strain MY3 falls in clade 'Nitrosocosmicus' of the thaumarchaeotal group I.
View Article and Find Full Text PDFAmmonia-oxidizing archaea (AOA), that is, members of the Thaumarchaeota phylum, occur ubiquitously in the environment and are of major significance for global nitrogen cycling. However, controls on cell growth and organic carbon assimilation by AOA are poorly understood. We isolated an ammonia-oxidizing archaeon (designated strain DDS1) from seawater and used this organism to study the physiology of ammonia oxidation.
View Article and Find Full Text PDFRationale: Intact polar lipids (IPLs) are the building blocks of cell membranes, and amino acid containing IPLs have been observed to be involved in response to changing environmental conditions in various species of bacteria. High-performance liquid chromatography/mass spectrometry (HPLC/MS) has become the primary method for analysis of IPLs. Many glycerol-free amino acid containing membrane lipids (AA-IPLs), which are structurally different than abundant aminophospholipids, have not been characterized using HPLC/MS.
View Article and Find Full Text PDFTwo isolates of aerobic methanotrophic bacteria, strains Sph1T and Sph2, were obtained from cold methane seeps in a floodplain of the river Mukhrinskaya, Irtysh basin, West Siberia. Another morphologically and phenotypically similar methanotroph, strain OZ2, was isolated from a sediment of a subarctic freshwater lake, Archangelsk region, northern Russia. Cells of these three strains were Gram-stain-negative, light-pink-pigmented, non-motile, encapsulated, large cocci that contained an intracytoplasmic membrane system typical of type I methanotrophs.
View Article and Find Full Text PDFAnaerobic enrichments with acetate as electron donor and carbon source, and elemental sulfur as electron acceptor at 4 M NaCl using anaerobic sediments and brines from several hypersaline lakes in Kulunda Steppe (Altai, Russia) resulted in isolation in pure culture of four strains of obligately anaerobic haloarchae growing exclusively by sulfur respiration. Such metabolism has not yet been demonstrated in any known species of Halobacteria, and in the whole archaeal kingdom, acetate oxidation with sulfur as acceptor was not previously demonstrated. The four isolates had nearly identical 16S rRNA gene sequences and formed a novel genus-level branch within the family Halobacteriaceae.
View Article and Find Full Text PDFTwo isolates of aerobic, budding, pink-pigmented bacteria, designated strains PX4 and PT1, were isolated from a boreal peat bog and a forested tundra wetland. Cells of these strains were non-motile spheres that occurred singly or in short chains. Novel isolates were capable of growth at pH values between 3.
View Article and Find Full Text PDFUnlabelled: Geothermal and hypersaline environments are rich in virus-like particles, among which spindle-shaped morphotypes dominate. Currently, viruses with spindle- or lemon-shaped virions are exclusive to Archaea and belong to two distinct viral families. The larger of the two families, the Fuselloviridae, comprises tail-less, spindle-shaped viruses, which infect hosts from phylogenetically distant archaeal lineages.
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