| isolation and some properties of nad+ reductase of the green photosynthetic bacterium prosthecochloris aestuarii. | nad+ reductase of the green photosynthetic bacterium prosthecochloris aestuarii was isolated and purified by ammonium sulfate fractionation, deae-cellulose column chromatography, and sephadex g-200 gel filtration. this enzyme is an fad-containing flavoprotein and has absorption maxima at 485 (shoulder0 452, 411, and 385 nm (the 411 nm band is due to cytochrome). the molecular weight of the enzyme as determined by gel filtration using sephadex g-200 is 119,000. the enzyme catalyzes the reduction ... | 1976 | 5430 |
| on the ecology of marine chromatiaceae and chlorobiaceae (author's transl). | number and genera (types) of phototrophic red and green sulfur bacteria have been determined in the upper layer of eleven marine sediment samples from the euphotic zone in the mediterranean sea. origin and nature of the sediment samples are given as well as their ph, total nitrogen and sulfide content. the results show that the sediments studied did not provide good growth conditions for chromatiaceae (chromatium, thiocystis, thiocapsa) and chlorobiaceae (prosthecochloris). the total number of t ... | 1976 | 9896 |
| axial ligation and heme environment in cytochrome c-555 from prosthecochloris aestuarii. investigation by absorption and solvent perturbation difference spectroscopy. | the near-ir absorption spectrum indicated that methionine is the sixth axial heme iron ligand in prosthecochloris aestuarii cytochrome c-555. the heme environment has been investigated by the technique of solvent perturbation difference spectroscopy. the heme octapeptide from cytochrome c plus added imidazole was used as a model compound for the fully exposed chromophore. the heme was found to be minimally exposed to solvent. a comparison was made with cytochrome c, as to the possible causes of ... | 1978 | 204338 |
| the redox properties and heme environment of cytochrome c-551.5 from desulfuromonas acetoxidans. | the environment of the three heme groups in cytochrome c-551.5 from desulfuromonas acetoxidans was investigated by the technique of solvent perturbation difference spectroscopy. the hemeoctapeptide from cytochrome c plus added imidazole was used as a model compound for the fully exposed chromophore. the average heme exposure in both the ferric and ferrous cytochromes c-551.5 was found to be considerably greater than that previously observed for the monoheme mitochondrial cytochrome c and prosthe ... | 1979 | 231458 |
| structure of a bacteriochlorophyll a-protein from the green photosynthetic bacterium prosthecochloris aestuarii. | | 1979 | 490647 |
| photochemically active pigment-protein complexes from the green photosynthetic bacterium prosthecochloris aestuarii. | photochemically active pigment-protein complexes were prepared from a bacteriochlorophyll a containing membrane preparation of the green photosynthetic bacterium prosthecochloris aestuarii. the preparations contained about 75 and 35 bacteriochlorophyll a molecules per reaction center and had molecular weights of 6 . 10(5) and 3.5 . 10(5), respectively. some of the other properties of these preparations are described. | 1979 | 508734 |
| derivative absorption spectroscopy from 5--300 k of prosthecochloris aestuarii. | absorption spectra of the bacteriochlorophyll a-protein from prosthecochloris aesturaii were measured at temperatures from 2.9 to 300 k. fourth and eight derivatives of the spectra were calculated from the digital data. from an analysis of 34 scans taken from 750 to 850 nm at 5 k, and 130 scans taken from 822 to 838 nm, we find evidence for nine peaks, six of which are probably 0--0 excitonic and three probably higher vibronic features. the major peaks are resolved in the derivative spectra to 3 ... | 1978 | 687607 |
| [new brown chlorobacteria prosthecochloris phaeoasteroidea nov. sp]. | two strains of new photosynthetic bacteria were isolated from salt meromictic lakes mogilnoye and faro. the bacteria are abligate phototrophic anaerobic cultures which utilize h2s as an electron donor by oxidizing it to elementary sulphur and sulphates. sulphur is liberated outside the cell. the cultures contain bacteriochlorophyll e and carotenoids of the isorenierathene type. photosynthetic structures are represented by chlorobium-vesicles. according to these properties, the cultures belong to ... | 1976 | 979684 |
| a morphological study of anaerobic bacteria from the hypolimnia of two michigan lakes. | dense populations of anaerobic bacteria were found sequentially layered below the thermocline in two eutrophic lakes in southwest michigan. phase and electron microscopy of whole cells and thin sections were used to reveal the in situ morphology of the dominant members of the community. the predominant chlorophyll-containing bacteria were identified on the basis of their morphology to be members of the genera pelodictyon, prosthecochloris, clathrochloris, chlorochromatium, pelochromatium, thiope ... | 1975 | 1090350 |
| the structure of anaerobic bacterial communities in the hypolimnia of several michigan lakes. | the structure of bacterial communities, the distribution of sulfide and oxygen, bacteriochlorophyll concentrations, and the temperature profile were determined for the anaerobic hypolimnia of two lakes in southern michigan. information from these studies, plus qualitative observations of two other lakes and two ponds over a 4-year period were used to correlate the spatial distribution of the populations, cell size, arrangement of photosynthetic vesicles or lamellae, presence of gas vacuoles or ... | 1975 | 1090351 |
| 5s rrna sequences of representatives of the genera chlorobium, prosthecochloris, thermomicrobium, cytophaga, flavobacterium, flexibacter and saprospira and a discussion of the evolution of eubacteria in general. | 5s rrna sequences were determined for the green sulphur bacteria chlorobium limicola, chlorobium phaeobacteroides and prosthecochloris aestuarii, for thermomicrobium roseum, which is a relative of the green non-sulphur bacteria, and for cytophaga aquatilis, cytophaga heparina, cytophaga johnsonae, flavobacterium breve, flexibacter sp. and saprospira grandis, organisms allotted to the phylum 'bacteroides-cytophaga-flavobacterium' and relatives as determined by 16s rrna analyses. by using a cluste ... | 1990 | 1693658 |
| structure and x-ray amino acid sequence of a bacteriochlorophyll a protein from prosthecochloris aestuarii refined at 1.9 a resolution. | the structure of the water-soluble bacteriochlorophyll a protein (bchl protein) from the green photosynthetic bacterium prosthecochloris aestuarii has been refined at 1.9 a resolution to a crystallographic residual of 18.9%. the refinement was carried out without knowledge of the amino acid sequence and has led to an "x-ray sequence". the structure consists of seven bchl molecules enclosed within a protein "bag" and the refinement supports the general conformation of the molecule described previ ... | 1986 | 3735428 |
| 13c nmr evidence for bacteriochlorophyll c formation by the c5 pathway in green sulfur bacterium, prosthecochloris. | the 13c nmr spectra of the pheophorbide of bacteriochlorophyll c, formed in the presence of l-[1-13c]glutamate and [2-13c]glycine and [13c]bicarbonate in prosthecochloris aestaurii, were analysed. the isotope in the glutamate was specifically incorporated into the eight carbon atoms in the tetrapyrrole macrocycle derived from the c-5 of 5-aminolevulinic acid, while no specific enrichment of these eight carbon atoms was observed in the spectrum of the pigment formed in the presence of [2-13c]glyc ... | 1986 | 3743570 |
| incidence of prosthecate bacteria in a polluted stream. | water samples were collected aseptically several times throughout the year at nine stations on the red cedar river, a stream flowing through farmland and receiving effluent from several municipalities in central michigan. total prosthecate bacteria were enumerated by both direct and viable counting techniques. by direct techniques, these bacteria accounted for 0.62 to 1.1% of the total microflora during the study. the predominant type of appendaged bacteria was the caulobacters (caulobacter, ast ... | 1971 | 4943266 |
| a new phototrophic green sulphur bacterium. prosthecochloris aestuarii nov. gen. nov. spec. | | 1970 | 5453898 |
| fluorescence emission spectra of cells and subcellular preparations of a green photosynthetic bacterium. effects of dithionite on the intensity of the emission bands. | fluorescence emission spectra were measured of intact cells and subcellular preparations of the green photosynthetic bacterium prosthecochloris aestuarii in the presence and in the absence of dithionite. a 3--5-fold increase in bacteriochlorophyll a fluorescence at 816 nm occurred upon addition of dithionite in a membrane vesicle preparation (complex i), in a photochemically active pigment-protein complex and in a bacteriochlorophyll a protein complex free from reaction centers. the pigment-prot ... | 1980 | 7236635 |
| seven-fold exciton splitting of the 810-nm band in bacteriochlorophyll a-proteins from green photosynthetic bacteria. | we report comparative absorbance and fourth derivative absorbance spectra of two different bacteriochlorophyll a-proteins at 5 k in each of two different cryogenic solvent mixtures. in previous studies at 5 k each protein was observed in only one of these mixtures (not the same one). for the protein from prosthecochloris aestuarii strain 2k, whose structure is known, the solvent effect is relatively small; for the protein from chlorobium limicola f. sp. thiosulfatophilum strain 6230 (tassajara), ... | 1980 | 7388015 |
| orientation of pigments and pigment-protein complexes in the green photosynthetic bacterium prosthecochloris aestuarii. | the orientation of pigments and pigment-protein complexes of the green photosynthetic bacterium prosthecochloris aestuarii was studied by measurement of linear dichroism spectra at 295 and 100 k. orientation of intact cells and membrane vesicles (complex i) was obtained by drying on a glass plate. the photochemically active pigment-protein complexes (photosystem-protein complex and reaction center pigment-protein complex) and the antenna bacteriochlorophyll a protein were oriented by pressing a ... | 1980 | 7426646 |
| a permanent hole burning study of the fmo antenna complex of the green sulfur bacterium prosthecochloris aestuarii. | a permanent hole burning study on the fenna-matthews-olson, or fmo, antenna complex of the green sulfur bacterium prosthecochloris aestuarii was carried out at 6 k. excitation resulted not only in relatively sharp features resonant with the burn wavelength but also in broad absorbance changes in the wavelength region of 800-820 nm. the shape of the latter changes was almost independent of the wavelength of excitation. evidence is given that they are induced by a different mechanism than that whi ... | 1998 | 9548735 |
| excited states and trapping in reaction center complexes of the green sulfur bacterium prosthecochloris aestuarii. | the excited states of bacteriochlorophyll (bchl) a were studied by pump-probe transient absorption spectroscopy in reaction center core (rcc), fenna-matthews-olson (fmo) and fmo-rcc complexes of the green sulfur bacterium prosthecochloris aestuarii. excitation at 790 or 835 nm resulted in rapid equilibration of the energy between the bchl a molecules of the rcc complex: within 1 ps, most of the excitations had relaxed to the lowest energy level (835 nm), as a result of strong interactions betwee ... | 1998 | 9692969 |
| chlorobium ferrooxidans sp. nov., a phototrophic green sulfur bacterium that oxidizes ferrous iron in coculture with a "geospirillum" sp. strain. | a green phototrophic bacterium was enriched with ferrous iron as sole electron donor and was isolated in defined coculture with a spirilloid chemoheterotrophic bacterium. the coculture oxidized ferrous iron to ferric iron with stoichiometric formation of cell mass from carbon dioxide. sulfide, thiosulfate, or elemental sulfur was not used as electron donor in the light. hydrogen or acetate in the presence of ferrous iron increased the cell yield of the phototrophic partner, and hydrogen could al ... | 1999 | 10415173 |
| dynamics of anoxygenic photosynthesis in an experimental green sulphur bacteria biofilm. | the dynamics of sulphide oxidation in an experimental biofilm of the green sulphur bacterium, prosthecochloris aestuarii, were studied using a newly developed light-dark cycling procedure. the biofilm was grown for 6 weeks in a benthic gradient chamber, in which gradients of light, sulphide and oxygen were imposed experimentally. the h2s concentrations and ph were measured with microsensors as a function of depth in the biofilm and of time after a change in illumination status. the sulphide oxid ... | 1999 | 11207748 |
| effect of light quality on sulfide photo-oxidation and growth in an artificial biofilm of the green sulfur bacterium prosthecochloris aestuarii. | we have succeeded in culturing an axenic biofilm of the green sulfur bacterium prosthecochloris aestuarii strain ce 2404 in an artificial sandy sediment under visible light (400-700 nm). this simulates the conditions of deep submerged sediments. a five-week incubation period, using a 16-hour light / 8-hour dark regime, was applied in the benthic gradient chamber (bgc). the biofilm was located below the oxygen penetration depth of 1.2 mm, namely between 1.5 and 2.5 mm and the biomass peak was at ... | 2002 | 16228511 |
| anaerobic oxidation of dissolved hydrogen sulfide in continuous culture of the phototrophic bacterium prosthecochloris aestuarii. | the anaerobic oxidation of dissolved h2s to elemental sulfur was studied at 23 degrees c and ph 6.5+/-0.3 in continuous culture of the phototrophic green sulfur bacterium prosthecochloris aestuarii. the number of cells formed in the cultures was proportional to the amount of h2s oxidized, and the growth yield was independent of light intensity. the specific growth rate was significantly dependent on the dissolved h2s concentration and light intensity. the kinetic data were analyzed with a rate e ... | 2000 | 16232737 |
| the structure of the fmo protein from chlorobium tepidum at 2.2 a resolution. | the bacteriochlorophyll protein, or fmo protein, from chlorobium tepidum, which serves as a light-harvesting complex and directs light energy from the chlorosomes attached to the cell membrane to the reaction center has been crystallized in a new space group. the crystals belong to the cubic space group p4(3)32 and the structure has been refined to a resolution 2.2 a with a r factor of 19.7%. the electron density maps show that the structure is composed of two beta sheets that surround seven bac ... | 2003 | 16245093 |
| diversity of anoxygenic phototrophic sulfur bacteria in the microbial mats of the ebro delta: a combined morphological and molecular approach. | the diversity of purple and green sulfur bacteria in the multilayered sediments of the ebro delta was investigated. specific oligonucleotide primers for these groups were used for the selective amplification of 16s rrna gene sequences. subsequently, amplification products were separated by denaturing gradient gel electrophoresis and sequenced, which yielded a total of 32 sequences. six of the sequences were related to different cultivated members of the green sulfur bacteria assemblage, whereas ... | 2005 | 16329919 |
| bacteriochlorophyll electronic transition moment directions in bacteriochlorophyll a-protein. | the low-temperature 800-nm band absorption and circular dichroism spectra of the bacteriochlorophyll (bchl) a-protein from prosthecochloris aestuarii strain 2k are analyzed theoretically. these spectra show considerable structure that is attributed primarily to resonance (exciton) interactions among the lowest singlet transitions of the bchl a molecules contained in each protein. we calculate these spectra from the known arrangement of the bchl molecules in the protein. with the conventional ass ... | 1978 | 16592579 |
| communities of green sulfur bacteria in marine and saline habitats analyzed by gene sequences of 16s rrna and fenna-matthews-olson protein. | communities of green sulfur bacteria were studied in selected marine and saline habitats on the basis of gene sequences of 16s rrna and the fenna- matthews-olson (fmo) protein. the availability of group-specific primers for both 16s rdna and the fmoa gene, which is unique to green sulfur bacteria, has, for the first time, made it possible to analyze environmental communities of these bacteria by culture-independent methods using two independent genetic markers. sequence results obtained with fmo ... | 2006 | 17236159 |
| [seasonal changes in the structure of the anoxygenic photosynthetic bacterial community in lake shunet, khakassia]. | seasonal studies of the anoxygenic phototrophic bacterial community of the water column of the saline eutrophic meromictic lake shunet (khakassia) were performed in 2002 (june) and 2003 (february-march and august). from the redox zone down, the lake water was of dark green color. green sulfur bacteria predominated in every season. the maximum number of green sulfur bacteria was 10(7) cells/ml in summer and 10(6) cells/ml in winter. a multi-syringe stratification sampler was applied for the study ... | 2007 | 17633417 |
| genome organization of treponema zioleckii. | genome analysis of treponema zioleckii proved that, in this bacterium, besides chromosomal dna, a relatively small extrachromosomal dna element is present. this element was shown to be a double-stranded circular plasmid dna of approximately 7 kbp; it was designated as pkt. the plasmid was characterized by molecular and bioinformatic analysis. no pkt homologous dna sequences were detected in other rumen treponema strains. the overall g+c content of the pkt plasmid is approximately 56 %, which is ... | 2008 | 18661302 |
| chirality-based signatures of local protein environments in two-dimensional optical spectroscopy of two species photosynthetic complexes of green sulfur bacteria: simulation study. | two-dimensional electronic chirality-induced signals of excitons in the photosynthetic fenna-matthews-olson complex from two species of green sulfur bacteria (chlorobium tepidum and prosthecochloris aestuarii) are compared. the spectra are predicted to provide sensitive probes of local protein environment of the constituent bacteriochlorophyll a chromophores and reflect electronic structure variations (site energies and couplings) of the two complexes. pulse polarization configurations are desig ... | 2008 | 18676650 |
| diversity of beta-propeller phytase genes in the intestinal contents of grass carp provides insight into the release of major phosphorus from phytate in nature. | phytate is the most abundant organic phosphorus compound in nature, and microbial mineralization of phytate by phytase is a key process for phosphorus recycling in the biosphere. in the present study, beta-propeller phytase (bpp) gene fragments were readily amplified from the intestinal contents of grass carp (ctenopharyngodon idellus) directly or from phytate-degrading isolates from the same source, confirming the widespread occurrence of bpp in aquatic communities. the amounts of sequences col ... | 2009 | 19151187 |
| calculation of pigment transition energies in the fmo protein: from simplicity to complexity and back. | the fenna-matthews-olson (fmo) protein of green sulfur bacteria represents an important model protein for the study of elementary pigment-protein couplings. we have previously used a simple approach [adolphs and renger (2006) biophys j 91:2778-2797] to study the shift in local transition energies (site energies) of the fmo protein of prosthecochloris aestuarii by charged amino acid residues, assuming a standard protonation pattern of the titratable groups. recently, we have found strong evidence ... | 2008 | 17917787 |
| the structural basis for the difference in absorbance spectra for the fmo antenna protein from various green sulfur bacteria. | the absorbance spectrum of the fenna-matthews-olson protein--a component of the antenna system of green sulfur bacteria--is always one of two types, depending on the species of the source organism. the fmo from prosthecochloris aestuarii 2k has a spectrum of type 1 while that from chlorobaculum tepidum is of type 2. the previously reported crystal structures for these two proteins did not disclose any rationale that would explain their spectral differences. we have collected a 1.3 a x-ray diffra ... | 2009 | 19437128 |
| phylogeny and taxonomy of chlorobiaceae. | based on phylogenetic relationships found according to gene sequences of the 16s rrna and the fmo (fenna-matthews-olson protein) genes, and supported by the g + c content of the dna and sequence signatures, the strains and species of green sulfur bacteria have been grouped into a phylogenetic system. since properties used previously for classification such as cell morphology, photosynthetic pigments and substrate utilization do not conform with their phylogeny, a reassignment of strains to speci ... | 2010 | 20094791 |
| how proteins trigger excitation energy transfer in the fmo complex of green sulfur bacteria. | a simple electrostatic method for the calculation of optical transition energies of pigments in protein environments is presented and applied to the fenna-matthews-olson (fmo) complex of prosthecochloris aestuarii and chlorobium tepidum. the method, for the first time, allows us to reach agreement between experimental optical spectra and calculations based on transition energies of pigments that are calculated in large part independently, rather than fitted to the spectra. in this way it becomes ... | 2006 | 16861264 |
| unique communities of anoxygenic phototrophic bacteria in saline lakes of salar de atacama (chile): evidence for a new phylogenetic lineage of phototrophic gammaproteobacteria from puflm gene analyses. | phototrophic bacteria are important primary producers of salt lakes in the salar de atacama and at times form visible mass developments within and on top of the lake sediments. the communities of phototrophic bacteria from two of these lakes were characterized by molecular genetic approaches using key genes for the biosynthesis of the photosynthetic apparatus in phototrophic purple bacteria (puflm) and in green sulfur bacteria (fmoa). terminal restriction fragment length polymorphism of the pufl ... | 2010 | 20868378 |
| mechanisms and evolution of oxidative sulfur metabolism in green sulfur bacteria. | green sulfur bacteria (gsb) constitute a closely related group of photoautotrophic and thiotrophic bacteria with limited phenotypic variation. they typically oxidize sulfide and thiosulfate to sulfate with sulfur globules as an intermediate. based on genome sequence information from 15 strains, the distribution and phylogeny of enzymes involved in their oxidative sulfur metabolism was investigated. at least one homolog of sulfide:quinone oxidoreductase (sqr) is present in all strains. in all sul ... | 2011 | 21833341 |
| [seasonal changes in the structure of the anoxygenic phototrophic bacterial community in lake mogilnoe, a relict lake on kil'din island in the barents sea]. | an anaerobic phototrophic bacterial community in lake mogilnoe, a relict lake on kil'din island in the barents sea, was studied in june 1999 and september 2001. irrespective of the season, the upper layer of the anaerobic zone of this lake had a specific species composition of sulfur phototrophic bacteria, which were dominated by the brown-colored green sulfur bacterium chlorobium phaeovibrioides. the maximum number of phototrophic sulfur bacteria was observed in june 1999 at a depth of 9 m, whi ... | 2005 | 16315987 |
| green sulfur bacteria from hypersaline chiprana lake (monegros, spain): habitat description and phylogenetic relationship of isolated strains. | the 'salada de chiprana' (chiprana lake) is a hypersaline (30-73 per thousand), permanent and shallow lake of endorheic origin in a semi-arid region of the ebro depression (aragon, spain). magnesium sulfate and sodium chloride represent the main salts of this athalassohaline environment. anoxic conditions occurred periodically in the bottom layers of the lake during the study period. when stratified, high sulfide concentrations (up to 7 mm) were measured in the hypolimnion. physical and chemical ... | 2002 | 16228510 |
| the quantitative relationship between structure and polarized spectroscopy in the fmo complex of prosthecochloris aestuarii: refining experiments and simulations. | new absorption, linear dichroism (ld) and circular dichroism (cd) measurements at low temperatures on the fenna-matthews-olson complex from prosthecochloris aestuarii are presented. furthermore, the anisotropy of fluorescence excitation spectra is measured and used to determine absolute ld spectra, i.e. corrected for the degree of orientation of the sample. in contrast to previous studies, this allows comparison of not only the shape but also the amplitude of the measured spectra with that calcu ... | 2002 | 16228505 |
| kinetics of absorbance and anisotropy upon excited state relaxation in the reaction center core complex of a green sulfur bacterium. | properties of the excited states in reaction center core (rcc) complexes of the green sulfur bacterium prosthecochloris aestuarii were studied by means of femtosecond time-resolved isotropic and anisotropic absorption difference spectroscopy at 275 k. selective excitation of the different transitions of the complex resulted in the rapid establishment of a thermal equilibrium. at about 1 ps after excitation, the energy was located at the lowest energy transition, bchl a 835. time constants varyin ... | 2000 | 16228492 |
| composition and optical properties of reaction centre core complexes from the green sulfur bacteria prosthecochloris aestuarii and chlorobium tepidum. | photosynthetically active reaction centre core (rcc) complexes were isolated from two species of green sulfur bacteria, prosthecochloris (ptc.) aestuarii strain 2k and chlorobium (chl.) tepidum, using the same isolation procedure. both complexes contained the main reaction centre protein psca and the iron-sulfur protein pscb, but were devoid of fenna-matthews-olson (fmo) protein. the chl. tepidum rcc preparation contained in addition pscc (cytochrome c). in order to allow accurate determination ... | 2000 | 16228441 |
| the impact of different intensities of green light on the bacteriochlorophyll homologue composition of the chlorobiaceae prosthecochloris aestuarii and chlorobium phaeobacteroides. | members of the chlorobiaceae and chloroflexaceae are unique among the phototrophic micro-organisms in having a remarkably rich chlorophyll pigment diversity. the physiological regulation of this diversity and its ecological implications are still enigmatic. the bacteriochlorophyll composition of the chlorobiaceae prosthecochloris aestuarii strain ce 2404 and chlorobium phaeobacteroides strain udg 6030 was therefore studied by both hplc with photodiode array (pda) detection and liquid chromatogra ... | 2004 | 15289552 |
| phylogenetic taxonomy of the family chlorobiaceae on the basis of 16s rrna and fmo (fenna-matthews-olson protein) gene sequences. | a new taxonomy of the green sulfur bacteria is proposed, based on phylogenetic relationships determined using the sequences of the independent 16s rrna and fmo (fenna-matthews-olson protein) genes, and supported by the dna g + c content and sequence signatures. comparison of the traditional classification system for these bacteria with their phylogenetic relationship yielded a confusing picture, because properties used for classification (such as cell morphology, photosynthetic pigments and subs ... | 2003 | 12892110 |
| experimental study of interactions between purple and green sulfur bacteria in sandy sediments exposed to illumination deprived of near-infrared wavelengths. | sedimentary biofilms of the green sulfur bacterium prosthecochloris aestuarii strain ce 2404, the purple sulfur bacterium thiocapsa roseopersicina strain 5811, and a mixed culture of both were cultured in fine sand (100- to 300-microm grain size) within counter gradients of oxygen and sulfide. the artificial sediments were exposed to illumination deprived of near-infrared light (nir) by filtering out the wavelengths longer than 700 nm to simulate the critical light conditions in submerged aquati ... | 2002 | 12039757 |
| light responses in the green sulfur bacterium prosthecochloris aestuarii: changes in prosthecae length, ultrastructure, and antenna pigment composition. | the morphology (mainly prosthecae length), ultrastructure, and antenna pigment composition of the green sulfur bacterium prosthecochloris aestuarii changed when grown under different light intensities. at light intensities of 0.5 and 5 micromol quanta m(-2) s(-1), the cells had a star-like morphology. prosthecae, the characteristic appendages of the genus prosthecochloris, were 232 nm and 194 nm long, respectively. in contrast, when grown at 100 micromol quanta m(-2) s(-1), these appendages were ... | 2001 | 11685372 |
| electron transfer in reaction center core complexes from the green sulfur bacteria prosthecochloris aestuarii and chlorobium tepidum. | electron transfer in reaction center core (rcc) complexes from the green sulfur bacteria prosthecochloris aestuarii and chlorobium tepidum was studied by measuring flash-induced absorbance changes. the first preparation contained approximately three iron-sulfur centers, indicating that the three putative electron acceptors f(x), f(a), and f(b) were present; the chl. tepidum complex contained on the average only one. in the rcc complex of ptc. aestuarii at 277 k essentially all of the oxidized pr ... | 2000 | 10852720 |
| dynamics of energy conversion in reaction center core complexes of the green sulfur bacterium prosthecochloris aestuarii at low temperature. | excited-state and electron-transfer dynamics at cryogenic temperature in reaction center core (rcc) complexes of the photosynthetic green sulfur bacterium prosthecochloris aestuarii were studied by means of time-resolved absorption spectroscopy, using selective excitaton of bacteriochlorophyll (bchl) a and of chlorophyll (chl) a 670. the results indicate that the bchls a of the rcc complex form an excitonically coupled system. relaxation of the excitation energy within the ensemble of bchl a mol ... | 1999 | 10529194 |
| a microsensor study of the interaction between purple sulfur and green sulfur bacteria in experimental benthic gradients. | > abstract the interaction between the purple sulfur bacterium thiocapsa roseopersicina and the green sulfur bacterium prosthecochloris aestuarii was studied in a gradient chamber under a 16-hours light-8-hours dark regime. the effects of interaction were inferred by comparing the final outcome of a mixed culture experiment with those of the respective axenic cultures using the same inoculation densities and experimental conditions. densities of bacteria were deduced from radiance microprofiles, ... | 1999 | 10227875 |
| on the influence of pigment-protein interactions on the energy transfer processes in photosynthetic membrane structures. | low-temperature heterogeneous absorption and circular dichroism spectra of the prosthecochloris aestuarii fmo complex were calculated within the framework of the mini-exciton theory including both the inhomogeneous distribution of exciton line frequencies and static random disorder of the pure electronic transitions of bchl molecules. the frequencies of the qy pure electronic transitions of bchl molecules immobilized by the fmo complex polypeptides were found by minimization of a functional whic ... | 1998 | 10024966 |
| the triplet state of the fmo complex of the green sulfur bacterium prosthecochloris aestuarii studied with single-crystal epr. | triplet-electron paramagnetic resonance (epr) spectra were obtained of single crystals of the fmo complex of the green sulfur bacterium prostecochloris aestuarii. the experiments support the results presented in a previous paper (louwe et al., j. phys. chem. 101 (1997) 11280), which showed that the experimental optical spectra of this pigment-protein complex are best reproduced by assuming that one bacteriochlorophyll (bchl 3) is energetically isolated and that this bchl is the triplet-carrying ... | 1998 | 9757080 |
| crystal structure of the bacteriochlorophyll a protein from chlorobium tepidum. | the bacteriochlorophyll (bchl) a protein from chlorobium tepidum, which participates in energy transfer in green photosynthetic bacteria, has been crystallized using the sitting drop method of vapor diffusion. x-ray diffraction data collected from these crystals indicate that the crystals belong to the cubic space group p4132 with cell dimensions of a=b=c=169.5 a. a native x-ray diffraction data set has been collected to a resolution of 2.2 a. the initial solution was determined by using the mol ... | 1997 | 9268671 |
| ultrafast absorption difference spectra of the fenna-matthews-olson protein at 19 k: experiment and simulations. | we describe simulations of absorption difference spectra in strongly coupled photosynthetic antennas. in the presence of large resonance couplings, distinctive features arise from excited-state absorption transitions between one- and two-exciton levels. we first outline the theory for the heterodimer and for the general n-pigment system, and we demonstrate the transition between the strong and weak coupling regimes. the theory is applied to fenna-matthews-olson (fmo) bacteriochlorophyll a protei ... | 1997 | 8994590 |
| the primary charge separation, cytochrome oxidation and triplet formation in preparations from the green photosynthetic bacterium prosthecochloris aestuarii. | flash-induced absorbance changes were measured in intact cells and subcellular preparations of the green photosynthetic bacterium prosthecochloris aestuarii. in complex i, a membrane vesicle preparation, photooxidation of the primary electron donor, p-840, and of cytochrome c-553 was observed. flash excitation of the photosystem pigment complex caused in addition the generation of a bacteriochlorophyll a triplet. triplet formation was the only reaction observed after flash excitation in the reac ... | 1981 | 6260159 |
| the complete amino acid sequence of a bacteriochlorophyll a-protein from prosthecochloris aestuarii. | the amino acid sequence of a bacteriochlorophyll a-protein from the green photosynthetic bacterium prosthecochloris aestuarii strain 2k has been determined. use was made of a tentative sequence deduced from a 2.8-a electron density map of the protein to help locate sequenced peptides. the polypeptide chain consists of 366 amino acids. the identities of 5 amino acids that ligand to the magnesium atoms of 5 of the 7 bacteriochlorophyll molecules present in each subunit of the trimeric complex have ... | 1986 | 3949780 |
| structure of a bacteriochlorophyll a-protein from prosthecochloris aestuarii. | | 1976 | 1053056 |
| light-induced oxidation-reduction reactions of cytochromes in the green sulfur photosynthetic bacterium prosthecochloris aesturarii. | the light-induced oxidation-reduction reactions of cytochromes in intact cells, starved cells, and chlorobium vesicle fractions of the green sulfur photosynthetic bacterium prosthecochloris aesturarii were studied under anaerobic conditions. on the basis of both kinetic and spectral properties, at least three cytochrome species were found to be involved in the light-induced oxidation-reduction reactions of intact cells. these cytochromes were designated according to the positions of alpha-band m ... | 1976 | 1010847 |
| linear dichroism of electric field oriented bacteriochlorophyll alpha-protein from green photosynthetic bacteria. | bacteriochlorophyll alpha-protein from prosthecochloris aestuarii strain 2k was oriented in a pulsed electric field. the room temperature linear dichroism spectrum of the oriented protein in the qy region of the bacteriochlorophyll alpha absorption exhibits a single asymmetrical peak at 813 nm with a shoulder extending to the blue. the approximately equal 12 nm fullwidth of the linear dichroism peak is only about half that of the 300 k absorption spectrum. the linear dichroism at 813 nm was not ... | 1978 | 687613 |
| prosthecochloris indica sp. nov., a novel green sulfur bacterium from a marine aquaculture pond, kakinada, india. | a green sulfur bacterium, strain jags6t was isolated from a marine aquaculture pond located near kakinada on the east coast of india. cells of strain jags6t were gram-negative, non-motile, coccoid, 1-1.2 microm in diameter, with prosthecae. phylogenetic analysis on the basis of 16s rrna gene sequences showed that strain jags6t clusters with members of the genus prosthecochloris and the sequence similarity with the nearest relative, prosthecochloris vibrioformis, is 96.7%. cultures of strain jags ... | 2009 | 19436133 |
| comparative genomics of green sulfur bacteria. | eleven completely sequenced chlorobi genomes were compared in oligonucleotide usage, gene contents, and synteny. the green sulfur bacteria (gsb) are equipped with a core genome that sustains their anoxygenic phototrophic lifestyle by photosynthesis, sulfur oxidation, and co(2) fixation. whole-genome gene family and single gene sequence comparisons yielded similar phylogenetic trees of the sequenced chromosomes indicating a concerted vertical evolution of large gene sets. chromosomal synteny of g ... | 2010 | 20099081 |
| isolation and properties of photochemically active reaction center complexes from the green sulfur bacterium prosthecochloris aestuarii. | a new and rapid procedure was developed for the isolation of the reaction center core (rcc)-complex from the green sulfur bacterium prosthecochloris aestuarii. reaction center preparations containing the fenna matthews olson (fmo) protein were also obtained. the procedure involved incubation of broken cells with the detergents triton x-100 and sb12, sucrose gradient centrifugation and hydroxyapatite chromatography. three different pigment protein complexes were obtained: one containing (about) t ... | 1997 | 9369489 |