| rhodocista centenaria vs rhodospirillum centenum: a reply to gest and favinger. | | 2001 | 11321119 |
| phylogenetic relationships of the helical-shaped bacteria in the alpha proteobacteria inferred from 16s rdna sequences. | 16s ribosomal rna gene sequences from seven strains of aquaspirillum peregrinum, aqu. itersonii, aqu. polymorphum, and oceanospirillum pusillum were compared with homologous sequences from other members of helical-shaped bacteria. the bootstrapped neighbor-joining tree, inferred from 887 aligned sites, placed the spirillum taxa assigned to aquaspirillum, oceanospirillum, azospirillum, magnetospirillum, rhodospirillum, and rhodocista of the proteobacteria in seven clusters of alpha proteobacteria ... | 1997 | 12501339 |
| [characterization and phylogenic analysis on a new isolate of genus rhodocista]. | a strain of purple non sulfur bacteria was isolated from waste water plant in beijing. it is phototaxic, and can converted the vibrioid cells into thick-wall cyst. internal synthetic membrane is present as lamellae. it has a low absorption maxima at 798 nm. and require thiamine and vitamin b12 as growth factors. it can use succinate as carbon and energy source, but glucose can not be used. it can not grow in 3% nacl and had q-9 as major quinone. the 16s rrna gene was amplified, cloned and sequen ... | 2000 | 12548872 |
| "paraffin wax-overlay of pour plate", a method for the isolation and enumeration of purple non-sulfur bacteria. | a modification of pour plate technique with an overlay of wax was used for isolation and enumeration of purple non-sulfur bacteria (pnsb) with equal efficiency as that of agar shake culture. the total count of pnsb ranged from 10(5)-10(8) cfu g dry soil(-1) and belonged to the genera of rhodobacter, rhodopseudomonas, rhodocista and rubrivivax. | 2004 | 15488284 |
| defluvicoccus vanus gen. nov., sp. nov., a novel gram-negative coccus/coccobacillus in the 'alphaproteobacteria' from activated sludge. | a novel gram-negative coccus/coccobacillus, strain ben 114(t), growing in tetrads, clusters or aggregates, was isolated from activated sludge by micromanipulation. 16s rrna gene sequence analysis revealed that it belonged to the 'alphaproteobacteria', with no close relatives among cultured bacterial isolates. on the basis of phylogenetic data, this organism is considered to belong to a new genus, defluvicoccus, represented by the species defluvicoccus vanus sp. nov., a name chosen because of the ... | 2005 | 16166717 |
| structural role of tyrosine 98 in photoactive yellow protein: effects on fluorescence, gateway, and photocycle recovery. | we have recently shown that the y98q mutant of pyp has a major effect on the photocycle kinetics ( approximately 40 times slower recovery). we have now determined the crystal structure of y98q at 2.2 a resolution to reveal the role of residue y98 in the pyp photocycle. although the overall structure is very similar to that of wt, we observed two major effects of the mutation. one obvious consequence is a conformational change of the beta4-beta5 loop, which includes a repositioning of residue m10 ... | 2007 | 17198379 |
| the photoactivated pyp domain of rhodospirillum centenum ppr accelerates the recovery of the bacteriophytochrome domain after white light illumination. | ppr from the purple phototrophic bacterium, rhodospirillum centenum (also known as rhodocista centenaria), is a hybrid of photoactive yellow protein (pyp), bacteriophytochrome (bph), and histidine kinase (hk) domains. the holo-ppr (containing both chromophores) exhibits characteristic absorption maxima at 435 nm due to the pyp domain and at 400, 642, and 701 nm due to the bph domain. illumination of the ppr with white light causes a bleach of both pyp and bph absorbance; weak blue light primaril ... | 2007 | 17590020 |
| physiological versatility of the genus rhodocista. | a new purple bacterium (strain t4), capable of heterotrophic aerobic and phototrophic anaerobic growth, was isolated from waste water of a noodle factory near hanoi, vietnam. a comparison of 16s rdna sequences revealed its association with the genus rhodocista. the isolate, tentatively named "rhodocista hanoiensis", forms cysts after growth on butyrate-containing plates at 42 degrees c. the vegetative cells form short (under aerobic conditions) or long curve-shaped rods. in contrast to other spe ... | 2007 | 17913074 |
| regulation of aerobic photosystem synthesis in the purple bacterium rhodospirillum centenum by crtj and aerr. | genes coding for putative crtj and aerr homologs were identified and characterized in the purple photosynthetic bacterium rhodospirillum centenum (also known as rhodocista centenaria), an organism that synthesizes photopigments even under highly aerated conditions. mutational analysis indicated that in rsp. centenum, gene crtj codes for a repressor for photosynthesis gene expression as in rhodobacter capsulatus, which exhibits a high level of oxygen repression of photosystem synthesis. in contra ... | 2008 | 18846293 |
| prokaryotic phototaxis. | microorganisms have various mechanisms at their disposal to react to (changes in) their ambient light climate (i.e., intensity, color, direction, and degree of polarization). of these, one of the best studied mechanisms is the process of phototaxis. this process can be described as a behavioral migration-response of an organism toward a change in illumination regime. in this chapter we discuss three of these migration responses, based on swimming, swarming, and twitching motility, respectively. ... | 2009 | 19763957 |
| phaeovibrio sulfidiphilus gen. nov., sp. nov., phototrophic alphaproteobacteria isolated from brackish water. | two strains (ja480(t) and ja481) of phototrophic alphaproteobacteria were isolated from sediment samples collected from brackish water near nagapattinam, india. they were gram-negative, vibrioid cells containing bacteriochlorophyll a and rhodopin as major photosynthetic pigments. most cells of both strains were non-flagellated; 1 % of cells showed two monopolar flagella. cells showed positive phototaxis. both strains showed chimeric intracellular photosynthetic membranes, where both lamellar sta ... | 2011 | 20495036 |
| the photosensor protein ppr of rhodocista centenaria is linked to the chemotaxis signalling pathway. | rhodocista centenaria is a phototrophic α-proteobacterium exhibiting a phototactic behaviour visible as colony movement on agar plates directed to red light. as many phototrophic purple bacteria r. centenaria possesses a soluble photoactive yellow protein (pyp). it exists as a long fusion protein, designated ppr, consisting of three domains, the pyp domain, a putative bilin binding domain (bbd) and a histidine kinase domain (pph). the ppr protein is involved in the regulation of polyketide synth ... | 2010 | 21062468 |
| characterization of a novel spirillum-like bacterium that degrades ferrioxamine-type siderophores. | a novel gram-negative spirillum-like bacterium (asp-1) was isolated from lake water by enrichment culture on desferrioxamine b as sole source of carbon and energy. asp-1 was able to degrade the siderophores desferrioxamine b and e. the property of siderophore degradation was inducible in the presence of desferrioxamine b. the ferric complexes, however, were not measurably degraded but served as an iron source. degradation of desferrioxamines in culture was followed by measuring the residual ferr ... | 1996 | 8574095 |
| elstera litoralis gen. nov., sp. nov. isolated from stone biofilms of lake constance after enrichment with diatom exudates. | an alphaproteobacterium, strain dia-1t, was isolated from algae-dominated biofilms on stones from the littoral zone of lake constance, germany. this bacterium was isolated after initial enrichment in spent medium obtained after growth of a diatom culture. numerous sugars and few organic acids and alcohols serve as growth substrate. the bacterium grows slowly, is strictly aerobic but microaerophilic, and does not grow in cultures shaken under air. 16s rrna gene sequence analysis indicated that st ... | 2011 | 21948090 |
| a rapid and simple pcr method for identifying isolates of the genus azospirillum within populations of rhizosphere bacteria. | aims: to develop a rapid and simple genus-specific polymerase chain reaction (pcr) method for detecting and identifying isolates of the genus azospirillum which is well-recognized as plant growth-promoting rhizobacterium. methods and results: nine pairs of pcr primers were designed based on the azospirillum 16s rrna, ipdc, nifa, and nifh genes to assess their genus specificity by testing against 12 azospirillum (from seven species) and 15 non-azospirillum reference strains, as compared with th ... | 2011 | 21790914 |
| thermochromatium tepidum photoactive yellow protein/bacteriophytochrome/diguanylate cyclase: characterization of the pyp domain. | the purple phototrophic bacterium, thermochromatium tepidum, contains a gene for a chimeric photoactive yellow protein/bacteriophytochrome/diguanylate cyclase (ppd). we produced the tc. tepidum pyp domain (tt pyp) in escherichia coli, and found that it has a wavelength maximum at 358 nm due to a leu46 substitution of the color-tuning glu46 found in the prototypic halorhodospira halophila pyp (hh pyp). however, the 358 nm dark-adapted state is in a ph-dependent equilibrium with a yellow species a ... | 2005 | 15779902 |
| rhodobacter capsulatus photoactive yellow protein: genetic context, spectral and kinetics characterization, and mutagenesis. | a gene for photoactive yellow protein (pyp) was previously cloned from rhodobacter capsulatus (rc), and we have now found it to be associated with genes for gas vesicle formation in the recently completed genome sequence. however, the pyp had not been characterized as a protein. we have now produced the recombinant rcpyp in escherichia coli as a glutathione-s-transferase (gst) fusion protein, along with the biosynthetic enzymes, resulting in the formation of holo-rcpyp following cleavage of the ... | 2004 | 14967022 |
| rhodocista pekingensis sp. nov., a cyst-forming phototrophic bacterium from a municipal wastewater treatment plant. | a novel bacterial species, rhodocista pekingensis sp. nov., was isolated from a municipal wastewater treatment plant and characterized by polyphasic taxonomy. cells of r. pekingensis were gram-negative, motile by a single polar flagellum, vibrioid to spiral, 0.6-0.8 microm in width and 0.8-1.5 microm in length. r-bodies were not observed. phototrophically grown cells contained lamellar photosynthetic membranes and bacteriochlorophyll a. cell growth was anaerobically phototrophic or aerobically c ... | 2003 | 12892135 |
| design and application of new 16s rrna-targeted oligonucleotide probes for the azospirillum-skermanella-rhodocista-cluster. | the genera azospirillum, skermanella and rhodocista form a phylogenetic subgroup within the alfa subclass of proteobacteria. based on comparative 16s rrna sequence analysis a nested set of new oligonucleotide probes was designed. it comprises probes for the whole genus cluster azospirillum-skermanella-rhodocista, for the azospirilli subcluster i including a. lipoferum, a. doebereinerae, a. largimobile, a. brasilense and a. halopraeferens, for the azospirilli subcluster ii including a. amazonense ... | 2001 | 11403403 |