| phylogenetic analysis of the spirochetes. | the 16s rrna sequences were determined for species of spirochaeta, treponema, borrelia, leptospira, leptonema, and serpula, using a modified sanger method of direct rna sequencing. analysis of aligned 16s rrna sequences indicated that the spirochetes form a coherent taxon composed of six major clusters or groups. the first group, termed the treponemes, was divided into two subgroups. the first treponeme subgroup consisted of treponema pallidum, treponema phagedenis, treponema denticola, a thermo ... | 1991 | 1917844 |
| involvement of periplasmic fibrils in motility of spirochetes. | nonmotile (mot-) strains of spirochaeta aurantia and spirochaeta halophila were isolated with a procedure involving mutagenesis of motile wild-type cells. electron microscopy showed that a mot- mutant strain of s. halophia possessed incomplete periplasmic fibrils, inasmuch as most or all of the filamentous portion of the periplasmic fibrils was absent. some of the cells of this mot-, fibril-defective mutant strain lacked the filamentous portion of the periplasmic fibrils and formed proximal hook ... | 1980 | 7354002 |
| bacterial primary colonization and early succession on surfaces in marine waters as determined by amplified rrna gene restriction analysis and sequence analysis of 16s rrna genes. | the nearly universal colonization of surfaces in marine waters by bacteria and the formation of biofilms and biofouling communities have important implications for ecological function and industrial processes. however, the dynamics of surface attachment and colonization in situ, particularly during the early stages of biofilm establishment, are not well understood. experimental surfaces that differed in their degrees of hydrophilicity or hydrophobicity were incubated in a salt marsh estuary tida ... | 2000 | 10653705 |
| molecular evidence for novel planctomycete diversity in a municipal wastewater treatment plant. | we examined anoxic and aerobic basins and an anaerobic digestor of a municipal wastewater treatment plant for the presence of novel planctomycete-like diversity. three 16s rrna gene libraries were constructed by using a 16s rrna-targeted universal reverse primer and a forward pcr primer specific for planctomyces: phylogenetic analysis of 234 16s rrna gene sequences defined 110 operational taxonomic units. the majority of these sequences clustered with the four known genera, pirellula (32%), plan ... | 2003 | 14660385 |
| sulfate-reducing bacteria in tubes constructed by the marine infaunal polychaete diopatra cuprea. | marine infaunal burrows and tubes greatly enhance solute transport between sediments and the overlying water column and are sites of elevated microbial activity. biotic and abiotic controls of the compositions and activities of burrow and tube microbial communities are poorly understood. the microbial communities in tubes of the marine infaunal polychaete diopatria cuprea collected from two different sediment habitats were examined. the bacterial communities in the tubes from a sandy sediment di ... | 2004 | 15574900 |
| community composition of a hypersaline endoevaporitic microbial mat. | a hypersaline, endoevaporitic microbial community in eilat, israel, was studied by microscopy and by pcr amplification of genes for 16s rrna from different layers. in terms of biomass, the oxygenic layers of the community were dominated by cyanobacteria of the halothece, spirulina, and phormidium types, but cell counts (based on 4',6'-diamidino-2-phenylindole staining) and molecular surveys (clone libraries of pcr-amplified genes for 16s rrna) showed that oxygenic phototrophs were outnumbered by ... | 2005 | 16269778 |
| rapid and accurate diagnosis of human intestinal spirochetosis by fluorescence in situ hybridization. | human intestinal spirochetosis (his) is associated with overgrowth of the large intestine by spirochetes of the genus brachyspira. the microbiological diagnosis of his is hampered by the fastidious nature and slow growth of brachyspira spp. in clinical practice, his is diagnosed histopathologically, and a significant portion of cases may be missed. fluorescence in situ hybridization (fish) is a molecular method that allows the visualization and identification of single bacteria within tissue sec ... | 2009 | 19279178 |
| the selective value of bacterial shape. | why do bacteria have shape? is morphology valuable or just a trivial secondary characteristic? why should bacteria have one shape instead of another? three broad considerations suggest that bacterial shapes are not accidental but are biologically important: cells adopt uniform morphologies from among a wide variety of possibilities, some cells modify their shape as conditions demand, and morphology can be tracked through evolutionary lineages. all of these imply that shape is a selectable featur ... | 2006 | 16959965 |
| complete genome sequence of the termite hindgut bacterium spirochaeta coccoides type strain (spn1(t)), reclassification in the genus sphaerochaeta as sphaerochaeta coccoides comb. nov. and emendations of the family spirochaetaceae and the genus sphaerochaeta. | spirochaeta coccoides dröge et al. 2006 is a member of the genus spirochaeta ehrenberg 1835, one of the oldest named genera within the bacteria. s. coccoides is an obligately anaerobic, gram-negative, non-motile, spherical bacterium that was isolated from the hindgut contents of the termite neotermes castaneus. the species is of interest because it may play an important role in the digestion of breakdown products from cellulose and hemicellulose in the termite gut. here we provide a taxonomic re ... | 2012 | 22768363 |
| helicobacter pylori strains vary cell shape and flagellum number to maintain robust motility in viscous environments. | the helical shape of the human stomach pathogen helicobacter pylori has been suggested to provide mechanical advantage for penetrating the viscous stomach mucus layer. using single-cell tracking and quantitative morphology analysis, we document marked variation in cell body helical parameters and flagellum number among h. pylori strains leading to distinct and broad speed distributions in broth and viscous gastric mucin media. these distributions reflect both temporal variation in swimming speed ... | 2016 | 26365708 |
| helicobacter pylori strains vary cell shape and flagellum number to maintain robust motility in viscous environments. | the helical shape of the human stomach pathogen helicobacter pylori has been suggested to provide mechanical advantage for penetrating the viscous stomach mucus layer. using single-cell tracking and quantitative morphology analysis, we document marked variation in cell body helical parameters and flagellum number among h. pylori strains leading to distinct and broad speed distributions in broth and viscous gastric mucin media. these distributions reflect both temporal variation in swimming speed ... | 2016 | 26365708 |
| intra- and interspecific comparisons of bacterial diversity and community structure support coevolution of gut microbiota and termite host. | we investigated the bacterial gut microbiota from 32 colonies of wood-feeding termites, comprising four microcerotermes species (termitidae) and four reticulitermes species (rhinotermitidae), using terminal restriction fragment length polymorphism analysis and clonal analysis of 16s rrna. the obtained molecular community profiles were compared statistically between individuals, colonies, locations, and species of termites. both analyses revealed that the bacterial community structure was remarka ... | 2005 | 16269686 |
| biology of moderately halophilic aerobic bacteria. | the moderately halophilic heterotrophic aerobic bacteria form a diverse group of microorganisms. the property of halophilism is widespread within the bacterial domain. bacterial halophiles are abundant in environments such as salt lakes, saline soils, and salted food products. most species keep their intracellular ionic concentrations at low levels while synthesizing or accumulating organic solutes to provide osmotic equilibrium of the cytoplasm with the surrounding medium. complex mechanisms of ... | 1998 | 9618450 |
| the tektin family of microtubule-stabilizing proteins. | tektins are insoluble alpha-helical proteins essential for the construction of cilia and flagella and are found throughout the eukaryotes apart from higher plants. being almost universal but still fairly free to mutate, their coding sequences have proved useful for estimating the evolutionary relationships between closely related species. their protein molecular structure, typically consisting of four coiled-coil rod segments connected by linkers, resembles that of intermediate filament (if) pro ... | 2008 | 18671835 |
| microbiomes of muricea californica and m. fruticosa: comparative analyses of two co-occurring eastern pacific octocorals. | octocorals are sources of novel but understudied microbial diversity. conversely, scleractinian or reef-building coral microbiomes have been heavily examined in light of the threats of climate change. muricea californica and muricea fruticosa are two co-occurring species of gorgonian octocoral abundantly found in the kelp forests of southern california, and thus provide an excellent basis to determine if octocoral microbiomes are host specific. using illumina miseq amplicon sequencing and replic ... | 2016 | 27445997 |