physiological and morphological observations on thiovulum sp.cell suspensions of thiovulum sp., collected from enrichment cultures, were grown, maintained, and harvested for periods up to 7 months. in open-flow cultures run with aerated seawater, a continuous supply of hydrogen sulfide was provided by diffusion through a semipermeable membrane from either a live culture of desulfovibrio esturaii, neutralized sodium sulfide, or a n2-h2s gas mixture. attempts to grow thiovulum in pure culture failed despite variation in concentrations of dissolved oxygen an ...1978101531
rapid bacterial swimming measured in swarming cells of thiovulum majus.swarming cells of the sulfide-oxidizing bacterium thiovulum majus form bands and show bioconvective patterns of swimming when placed in vessels containing h2s/o2 interfaces. measurements of swimming velocities with video microscopic recordings under such conditions showed mean cell speeds as high as 615 microns s-1, unprecedented in bacteria.19892498293
campylobacter pylori, the spiral bacterium associated with human gastritis, is not a true campylobacter sp.comparison of partial 16s rrna sequences from representative campylobacter species indicates that the campylobacter species form a previously undescribed basic eubacterial group, which is related to the other major groups only by very deep branching. this analysis was extended to include the spiral bacterium associated with human gastritis, campylobacter pylori (formerly campylobacter pyloridis). the distance between c. pylori and the other campylobacter species is sufficient to exclude the pylo ...19873571163
microbiological observations in the anoxic basin golfo dulce, costa rica.our basic microbiological studies of the water column and the sediment of golfo dulce, costa rica, were focused on aerobic and denitrifying sulfur-oxidizing bacteria and anaerobic sulfate-reducing bacteria. we observed no increasing numbers of total bacterial counts within the water column. although no oxygen was present hydrogen sulfide was only detectable close to the sediment. the highest numbers of sulfate-reducing bacteria measured by most-probable-number counts were found in or close to th ...19969393644
true chemotaxis in oxygen gradients of the sulfur-oxidizing bacterium thiovulum majus.observations of free-swimming thiovulum majus cells show that these bacteria exhibit a phobic response as well as true chemotaxis in oxygen gradients. both phenomena of their chemotactic behavior are integrated into a single model of helical klinotaxis, which is demonstrated by computer simulations.200111425757
[cytoplasm constituents of a sulfur containing bacterium thiovulum majus hinze]. 195713500691
[electron microscopic study of a sulfurous bacterium, thiovulum majus hinze]. 195813512302
observations on the morphology of thiovulum majus hinze. 196113870493
complex pattern formation of marine gradient bacteria explained by a simple computer model.we report on the formation of conspicuous patterns by the sulfide-oxidizing bacterium thiovulum majus and a recently described vibrioid bacterium. these microaerophilic bacteria form mucus veils on top of sulfidic marine sediment exhibiting regular spaced bacterial patterns (honeycombs, interwoven bands, or inverse honeycombs). a simple qualitative computer model, based on chemotaxis towards oxygen and the ability of the bacteria to induce water advection when attached, can explain the formation ...200515869964
assessment of anaerobic wastewater treatment failure using terminal restriction fragment length polymorphism analysis.the suitability of genetic fingerprinting to study the microbiological basis of anaerobic bioreactor failure is investigated.200516313419
big bacteria.a small number of prokaryotic species have a unique physiology or ecology related to their development of unusually large size. the biomass of bacteria varies over more than 10 orders of magnitude, from the 0.2 microm wide nanobacteria to the largest cells of the colorless sulfur bacteria, thiomargarita namibiensis, with a diameter of 750 microm. all bacteria, including those that swim around in the environment, obtain their food molecules by molecular diffusion. only the fastest and largest swi ...200111544351
phylogenetic relationships of thiomicrospira species and their identification in deep-sea hydrothermal vent samples by denaturing gradient gel electrophoresis of 16s rdna fragments.denaturing gradient gel electrophoresis (dgge) of pcr-amplified 16s rdna fragments was used to explore the genetic diversity of hydrothermal vent microbial communities, specifically to determine the importance of sulfur-oxidizing bacteria therein. dgge analysis of two different hydrothermal vent samples revealed one pcr band for one sample and three pcr bands for the other sample, which probably correspond to the dominant bacterial populations in these communities. three of the four 16s rdna fra ...19957545384
phylogenetic diversity of the bacterial community from a microbial mat at an active, hydrothermal vent system, loihi seamount, hawaii.the phylogenetic diversity of small-subunit rrna genes associated with the domain bacteria was examined (by using previously defined operational taxonomic units [c. l. moyer, f.c. dobbs, and d. m. karl, appl. environ. microbiol. 60:871-879, 1994]; those for pele's vents bacteria are hereafter abbreviated pvb otus) with samples from a microbial mat at an active, deep-sea hydrothermal vent system. a cluster of phylogenetically related pvb otus (otus 2, 3, 6, and 8) was closely affiliated with thio ...19957538279
ecology of the bacteria of the sulphur cycle with special reference to anoxic-oxic interface environments.h2s is produced as a main end-product of anaerobic mineralization in anoxic, sulphate-rich environments by a diverse population of sulphate-reducing bacteria. the sulphate reducers can carry out an almost complete oxidation of detrital organic matter to co2. the h2s consequently becomes an important electron carrier from the anoxic to the oxic world. thiobacilli and other colourless sulphur bacteria have the potential to oxidize the h2s at the oxic-anoxic interface in sediments or stratified wat ...19826127739
evolutionary relationships among sulfur- and iron-oxidizing eubacteria.some 37 reverse transcriptase, partial 16s rrna sequences from sulfur- and/or iron-oxidizing eubacteria, including sequences from species of the genera thiobacillus, thiothrix, thiomicrospira, acidophilium, "leptospirillum," thiovulum, and chlorobium, have been determined. in addition, 16s sequences from a number of unnamed sulfur- and/or iron-oxidizing bacteria from hydrothermal vent sites, from invertebrate-bacterial endosymbioses, and from various mineral recovery operations also have been de ...19921729214
two-dimensional patterns in bacterial veils arise from self-generated, three-dimensional fluid flows.the behavior of collections of oceanic bacteria is controlled by metabolic (chemotaxis) and physical (fluid motion) processes. some sulfur-oxidizing bacteria, such as thiovulum majus, unite these two processes via a material interface produced by the bacteria and upon which the bacteria are transiently attached. this interface, termed a bacterial veil, is formed by exo-polymeric substances (eps) produced by the bacteria. by adhering to the veil while continuing to rotate their flagella, the bact ...201120376573
colorless sulfur bacteria, beggiatoa spp. and thiovulum spp., in o(2) and h(2)s microgradients.the interactions between colorless sulfur bacteria and the chemical microgradients at the oxygen-sulfide interface were studied in beggiatoa mats from marine sediments and in thiovulum veils developing above the sediments. the gradients of o(2), h(2)s, and ph were measured by microelectrodes at depth increments of 50 mum. an unstirred boundary layer in the water surrounding the mats and veils prevented microturbulent or convective mixing of o(2) and h(2)s. the two substrates reached the bacteria ...198316346268
survey of motile microaerophilic bacterial morphotypes in the oxygen gradient above a marine sulfidic sediment.enrichment cultures for free-swimming microaerophilic bacteria were prepared from marine sulfidic sediment samples (nivå bay, denmark). we observed nine different morphotypes; three of these morphotypes represented already-described species, i.e., thiovulum majus, "candidatus ovobacter propellens," and an as-yet-unnamed large vibrioid bacterium. in addition, we observed several morphotypes of spirilla and one vibrioid morphotype. a common feature of all investigated bacteria was that they aggreg ...200516000777
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