Publications

[glucides of phormidium tenue].		1953	13067276
[cytology of cyanophycea. i. research on the substructure of phormidium uncinatum gom].		1956	13327991
[cytology of cyanophycea. ii. centroplasm and granular inclusions of phormidium uncinatum].		1956	13327992
artificial cultivation of a red-pigmented marine blue-green alga, phormidium persicinum.		1958	13525639
chemical analysis of a mucopolymer component in cell walls of the blue-green alga phormidium uncinatum.		1962	13894623
algal virus: isolation.	freshwater blue-green algae of the genera lyngbya, plectonema, and phormidium are susceptible to a virus recently isolated from a waste-stabilization pond. electron micrographs of a partially purified preparation show that the viral particle has an icosahedral structure about 66 mmicro in diameter.	1963	13976026
[amino acid composition of the blue-green algae phormidium uncinatum (ag) gom].		1965	5865402
[on the antagonism of atabrine and flavine nucleotides in the behavior of movement and reaction to light of phormidium uncinatum].		1966	5992184
preparation of metabolically active protoplasts and particle preparations from the blue-green alga, phormidium luridum.	a method is described for the preparation of metabolically active protoplasts from the blue-green alga, phormidium luridum. the isolated protoplasts are stable and are capable of endogenous respiration and photoassimilation of carbon dioxide at rates not appreciably different from the untreated filaments. the protoplasts can be ruptured by dilution of the stabilizing osmoticum and, therefore, they provide a convenient starting point for the production of cell-free preparations within a biochemic ...	1967	16656675
chromophores of allophycocyanin and r-phycocyanin.	the biliprotein allophycocyanin was purified from phormidium luridum, anabaena variabilis and plectonema boryanum. r-phycocyanin was purified from rhodymenia palmata. the chromophores were cleaved from the denatured protein by methanol hydrolysis. they were purified and crystallized as the dimethyl esters. chromatographic and absorption-spectral (visible-ultraviolet and infrared) comparisons with reference material have established phycocyanobilin as the chromophore of allophycocyanin. phycocyan ...	1967	16742564
photosynthetic reactions by lysed protoplasts and particle preparations from the blue-green alga, phormidium luridum.	reactions of photosynthetic electron transport and photophosphorylation were studied in preparations from the blue-green alga, phormidium luridum. osmotic lysis of protoplasts proved to be a superior technique for the production of cell-free preparations with high enzymatic activity. such lysed protoplasts sustain high rates of photophosphorylation coupled to the photo-reduction of nadp(+) or ferricyanide. p/2e(-) ratios close to unity were routinely observed. the same preparations, and also tho ...	1967	16656676
[effect of redox systems on the motility and the phototactic reactions of phormidium uncinatum].		1968	5709367
sterols: isolation from a blue-green alga.	a crystalline mixture of sterols was isolated from the filamentous blue-green alga phormidium luridum. the mixture consisted of unsaturated 24-ethylcholesterols possessing delta(7)-, delta(5,7)-, and delta(5)-bonds together with their delta(22)-derivatives and a small amount of cholesterol. the major component was 24-ethyl-delta(7)-cholestenol. squalene and phytol were also evident.	1968	5677529
respiration in blue-green algae.	the low rate of endogenous respiration exhibited by the blue-green algae anacystis nidulans and phormidium luridum was not increased by the addition of respiratory substrates. however, endogenous respiration was inhibited by low concentrations of cyanide and by high carbon monoxide tensions. in addition, the uncouplers dinitrophenol and carbonyl cyanide p-trifluoromethoxyphenylhydrazone both stimulated the respiratory rate. the transition of cells from the aerobic steady state to anaerobiosis wa ...	1969	4390093
sensitivity and resistance of a blue-green alga phormidium mucicola to streptomycin and penicillin.		1970	4990326
3-(3,4-dichlorophenyl)-1, 1-dimethylurea-insensitive oxygen production in a cell-free preparation from phormidium luridum that shows redox potential dependent coupling to one-electron oxidants.		1971	4995803
nitrogen metabolism of nostoc muscorum & phormidiu phormidium fragile.		1971	5004444
protein aggregation in c-phycocyanin. studies at very low concentrations with the photoelectric scanner of the ultracentrifuge.	solutions of c-phycocyanin of very low concentrations were examined by sedimentation-velocity studies in the spinco model e ultracentrifuge equipped with a photoelectric scanning system and a monochromator. at sufficiently low concentrations complete disaggregation from the hexamer to the monomer was observed. the equilibrium constant of monomer to hexamer was estimated to be approx. 10(30). for studies of aggregation over the complete range of concentration, c-phycocyanins from phormidium lurid ...	1971	5123877
c-phycocyanin from phormidium luridum. isolation of subunits.		1972	4627355
light effect on the internal osmotic pressure of the blue-green algae plectonema boryanum and phormidium luridum.		1972	4629378
participation of two photosystems in the photo-phobotaxis of phormidium uncinatum.		1974	4209298
requirement of low oxidation-reduction potential for photosynthesis in a blue-green alga (phormidium sp.).	photosynthesis in a phormidium species which forms dense conical-shaped structures in thermal springs is strongly inhibited by aeration but is stimulated by sulfide and other agents (cysteine, thioglycolate, sulfite) which lower the oxidation-reduction potential. the compact structures which this alga forms in nature may restrict oxygen penetration from the enviroment so that the anaerobic or microaerophilic conditions necessary ofr photosynthesis can develop. the alga may be defective in a re ...	1975	808187
allophycocyanin from the filamentous cyanophyte, phormidium luridum.	allophycocyanin from the filamentous cyanophyte, phormidium luridum, was purified by ammonium sulfate fractionation and ion exchange chromatography on brushite columns. the specific absorption coefficient (e 0.1% 1cm) of purified allophycocyanin was 6.1 in distilled water and 7.3 in 0.05 m potassium phosphate buffer (ph 7). absorption maxima of allophycocyanin occurred at 650, 618 (shoulder), 350, and 275 nm. circular dichroic spectra displayed positive ellipticity bands at 655 and 625 nm, and a ...	1975	809053
the effect of inhibitors on the electron flow triggering photo-phobic reactions in cyanophyceae.	1. since photo-phobic reactions in the blue green alga phormidium uncinatum seem to be triggered by changes of electron flow rates into or out of an electron pool situated in the electron transport chain between photo-system ii and i, the effect of inhibitors affecting the electron transport chain has been studied. 2. dose response curves of the phobic reaction have been measured by varying the trap energy in double beam light trap experiments with constant pairs of monochromatic light. from the ...	1975	808185
metabolism of delta-aminolevulinic acid in red and blue-green algae.	delta-aminolevulinic acid was incorporated in vivo into c-phycocyanin and b-phycoerythrin in two species of the rhodophyta (cyanidium caldarium, porphyridium cruentum) and three species of the cyanophyta (anacystis nidulans, plectonema boryanum, phormidium luridum). amino acid analysis of phycocyanin-(14)c from c. caldarium cells which had been incubated with delta-aminolevulinate-4-(14)c showed that 84% of the radioactivity incorporated was present in the phycocyanobilin chromophore and less th ...	1975	16659103
increase effected by calcium ion in the rate of oxygen evolution from preparations of phormidium luridum.	the presence of ca2+ causes a twentyfold or greater increase in the rate of oxygen evolution by cell-free preparations of phormidium luridum. the requirement for ca2+ is specific; other divalent cations are much less effective or are inhibitory. the rate of the hill reaction is maximal at 30 mm cacl2 in both detergent-free and brij 35 preparations. the 3-(3,4-dichlorophenyl)-1,1-dimethylurea-insensitive component of oxygen-evolving activity in each preparation also shows the requirement for adde ...	1976	1259961
further evidence for the electron pool hypothesis. the effect of kcn and dspd on the photophobic reaction in the filamentous blue-green alga phormidium uncinatum.	in continuation of experiments with photo-system ii inhibitors [3-(3,4-dichlorophenyl)-1,1-dimethylurea and 2,5-dibromo-3-methyl-6-isopropylbenzo-quinone] the effect of photosystem i inhibitors was studied. 1. neither the plastocyanin inhibitor, potassium cyanide, nor the ferredoxin antagonist, disalicyliden propandiamin, markedly affected those phobic reactions which are mediated by the electron transport via photosystem ii into the electron pool. 2. on the other hand those phobic reactions, wh ...	1976	828026
photosynthetic activities of membrane preparations of the blue-green alga phormidium luridum.	techniques have been developed for the isolation of whole spheroplaste and membrane preparations from the blue-green alga phormidium luridum which are active in photosystem-ii-sensitized and photosystem-i-sensitized electron-transport reactions and in photophosphorylation. attention is called to the necessity of supplying magnesium and phosphate throughout the preparative and assay procedures for obtaining active membranes. selective washing of a proper membrane preparation is shown to remove a ...	1976	823011
isolation and characterization of lipopolysaccharides from cell walls of blue-green algae of the genus phormidium.	lipopolysaccharide (lps) fractions were isolated from three species of blue-green algae of the genus phormidium, namely, p. africanum, p. laminosum, and p. uncinatum, by using a phenol-water procedure followed by exhaustive extraction with ammonium oxalate. the materials obtained were shown to be closely related biochemically. nearly 60% of the lps consisted of the polysaccharides galactose, glucose, mannose, xylose, arabinose, and rhamnose and an unidentified, fast-moving sugar residue. in addi ...	1977	404280
the photochemical and fluorescence properties of whole cells, spheroplasts and spheroplast particles from the blue-green alga phormidium luridum.	the photochemical activities and fluorescence properties of cells, spheroplasts and spheroplast particles from the blue-green alga phormidium luridum were compared. the photochemical activities were measured in a whole range of wavelengths and expressed as quantum yield spectra (quantum yield vs. wavelength). the following reactions were measured. photosynthesis (o2 evolution) in whole cells; hill reaction (o2 evolution) with fe(cn)63- and nadp as electron acceptors (photosystem ii and photosyst ...	1977	402150
antialgal substances for iodine-disinfected swimming pools.	forty substances were tested for antialgal activity against chlorella pyrenoidosa (wis. 2005) and phormidium inundatum (wis. 1093). c. pyrenoidosa exhibited greater resistance to adverse effects of test compounds than did p. inundatum. although several structurally unrelated compounds were inhibitory to both alga species, even at an initial concentration of 1.0 mg/liter, methylthio-s-triazines, ametryne, prometryne, and terbutryne, at 0.1 mg/liter, restricted growth to less than 25% of control ( ...	1977	596878
influence of electric fields on photophobic reactions in blue-green algae.	the effect of external electric fields on photo-accumulations of phormidium uncinatum in light traps has been studied. 1. in direct current fields the phobic reaction of trichoms leaving the light field is not impaired if a voltage of 2.5 v is not exceeded. with voltages between 3 and 7 v the trichoms are motile, but phobic reactions are cancelled, provided the organisms are oriented more or less parallel to the electric field lines. higher voltages cause the algae to die within minutes. 2. only ...	1977	410383
purification and primary structure of cytochrome f from the cyanobacterium, plectonema boryanum.	the amino acid sequence of the soluble c-type cytochrome, cytochrome f, from the cyanobacterium plectonema boryanum (also called phormidium luridum or schizothrix calcicola) has been determined. the proposed sequence consists of one polypeptide chain of 85 residues and has three asn-gly linkages. partly due to the presence of these asn-gly bonds, which readily undergo rearrangement, proteolytic digestion on the small amount of protein available was unsatisfactory. the structure was determined pa ...	1977	199428
preparation of active fractions enriched in photosystem i and photosystem ii from the thermophilic blue-green alga phormidium laminosum.		1978	105942
a high-potential redox component located within cyanobacterial photosystem ii.	the calcium-dependent oxygen evolution activity of preparations of phormidium luridum shows a marked selectivity in favor of ferricyanide over benzoquinone as hill oxidant. in addition, the rate of oxygen evolution increases with increasing solution redox potential over the range +350 to +550 mv vs. the standard hydrogen electrode. these properties pertain to both 3-(3,4-dichlorophenyl)-1,1-dimethylurea-sensitive and -insensitive fractions of the total oxygen evolution activity. neither changes ...	1978	102342
calcium and photosynthetic oxygen evolution in cyanobacteria.	calcium activation of oxygen evolution from french-press preparations of phormidium luridum is largely reversible upon removal of added ca(2+). activation occurs via a first-order binding with a dissociation constant of 2.8 mm. an 8-fold increase in oxygen evolution rate observed upon ca(2+) addition is accounted for by a 4-fold increase in the number of active photosynthetic units, and a doubling of turnover rate. while both ca(2+) and mg(2+) stimulate turnover, unit activation is ca(2+) specif ...	1978	102341
on the linkages between chromophore and protein in biliproteins, vii. amino acid sequence in the chromophore regions of c-phycoerythrin from pseudanabaena w 1173 and phormidium persicinum.	bilipeptides from all chromophore regions were prepared by trypsin digestion of c-phycoerythrin from pseudanabaena w 1173 and phormidium persicinum. analytical separation and quantitative determination of bilipeptides was achieved by isoelectric focusing, preparative isolation by gel chromatography and ion-exchange chromatography. amino acid analysis revealed cysteine as the only amino acid common to all chromopeptides. amino acid sequences were determined by edman degradation and the dansyl-edm ...	1978	417013
the epr spectrum of iron--sulphur centre b in photosystem 1 of phormidium laminosum.		1979	228979
[immunostimulating activity of the lipopolysaccharides of blue-green algae].	the whole cells of blue-gree algae and lipopolysaccharides isolated from these cells were shown to stimulate the production of macro-(mainly) and microglobulin antibodies in rabbits. the macro- and microphage indices in rabbits increased significantly after the injection of lps isolated from blue-green algae 24--48 hours before infecting the animals with a virulent y. pseudotuberculosis strain. besides, the inhibiting action of this strain on the migration of phagocytes to the site of infection ...	1979	117655
energy transfer among the chromophores in phycocyanins measured by picosecond kinetics.	energy-transfer processes in the algal light-harvesting proteins, the phycocyanins, have been studied by means of picosecond absorption spectroscopy. after excitation at 530 nm, the absorption at several wavelengths in the range 480--669 nm decayed with a short time constant (picosecond) and a long time constant (greater than 1 ns). for c-phycocyanin, energy transfer from the beta to the alpha subunits is interpreted as being a likely candidate for the short time constant; the long time constant ...	1979	115492
phycobilisomes from blue-green and red algae: isolation criteria and dissociation characteristics.	a general procedure for the isolation of functionally intact phycobilisomes was devised, based on modifications of previously used procedures. it has been successful with numerous species of red and blue-green algae (anabaena variabilis, anacystis nidulans, agmenellum quadruplicatum, fremyella diplosiphon, glaucosphaera vacuolata, griffithsia pacifica, nemalion multifidum, nostoc sp., phormidium persicinum, porphyridium cruentum, p. sordidum, p. aerugineum, rhodosorus marinus). isolation was car ...	1979	16660778
laboratory comparison of the effectiveness of several algicides on isolated swimming pool algae.	the most frequently encountered species of algae found in swimming pools in the phoenix metropolitan area were used to evaluate the laboratory effectiveness of five commercially available pool chemicals used for algal control. the pool algae used were the xanthophyte pleurochloris pyrenoidosa, the chlorophyte oocystis sp., and the cyanophytes phormidium minnesotense and plectonema sp. pad algae kill (a chlorine derivative) was effective in the control of all test organisms. algaedyn, a silver-co ...	1980	16345508
light-induced changes in allophycocyanin.	several lines of evidence indicate that allophycocyanin is the previously unidentified "phycochrome" observed in extracts of blue-green algae.fractions containing phycoerythrin, phycocyanin, and allophycocyanin and exhibiting light-induced absorbance changes were prepared from extracts of nostoc muscorum and fremyella diplosiphon by isoelectric focusing. illumination of such fractions with red light (650 nanometers) causes a reduction in absorbance at 620 nm ( approximately 1 to 2%) and an incre ...	1980	16661143
photosynthetic electron transport in a cell-free preparation from the thermophilic blue-green alga phormidium laminosum.	1. a cell-free preparation of membrane fragments was prepared from the thermophilic blue-green alga phormidium laminosum by lysozyme treatment of the cells followed by osmotic shock to lyse the spheroplasts. the membrane fragments showed high rates of photosynthetic electron transport and o2 evolution (180-250 mumol of o2/h per mg of chlorophyll a with 2,6-dimethyl-1,4-benzoquinone as electron acceptor). o2-evolution activity was stable provided that cations (e.g. 10mm-mg2+ or 100mm-na+) or glyc ...	1980	6772163
linear dichroism of microalgae, developing thylakoids and isolated pigment-protein complexes in stretched poly(vinyl alcohol) films at 77 k.	a variety of unicellular algae, thylakoids from higher plants in different stages of maturity and isolated pigment-protein complexes were oriented in stretched polyvinyl alcohol films. low temperature linear dichroism (ld) spectra of chlorella pyrenoidosa and higher plant thylakoids in the films were very similar to those obtained after orientation of similar samples using magnetic or electric fields. positive ld bands corresponding to chl a (670) and (682) and negative bands due to chl a (658) ...	1980	6774749
epr characteristics of oxygen-evolving photosytem ii particles from phormidium laminosum.	the epr characteristics of oxygen evolving particles prepared from phormidium laminosum are described. these particles are enriched in photosystem ii allowing epr investigation of signals which were previously small or masked by those from photosystem i in other preparations. epr signals from a signal ii species and high potential cytochrome beta-559 appear as they are photooxidised at cryogenic temperatures by photosystem ii. the signal ii species is a donor close to the photosystem ii reaction ...	1981	6263334
kinetics of reduction of the primary donor of photosystem ii. influence of ph in various preparations.	the kinetics of reduction of p-680, oxidized by a flash, have been measured with chloroplasts treated with tris, hydroxylamine or cholate, with ps-ii particles from phormidium (tris-treated) and with subchloroplast particles prepared with digitonin or triton. in all cases the electron transfer from d1 to p-680+ has similar rates, influenced similarly by ph and d1 has a one-electron capacity.	1981	6786346
gliding motility in aphanothece halophytica: analysis of wall proteins in mot mutants.	the unicellular cyanobacterium aphanothece halophytica (pcc 7418) is motile, and spontaneous nonmotile (mot) mutants accumulate when the organism is subcultured. analysis of mot mutants suggests that a glycoprotein in the cell wall is involved in the motility mechanism. proteins from the wall fraction of the wild type and five mot clones were analyzed by gradient sodium dodecyl sulfate-acrylamide gel electrophoresis. four clones were similar to the wild type, and one clone, mot-3, was missing a ...	1981	6793555
properties of oxygen-evolving photosystem-ii particles from phormidium laminosum, a thermophilic blue--green alga.	1. o2-evolving photosystem-ii particles from the thermophilic blue--green alga phormidium laminosum contained 1 mol of mn/13--17 mol of chlorophyll a compared with 1 mol of mn/65--75 mol of chlorophyll a in unfractionated membranes. 2. at least two-thirds of the mn in the photosystem-ii particles was removed by mild heating and by treatment with tris or edta, with concomitant loss of o2 evolution. however, irreversible inactivation was also caused by washing in buffers without mgcl2, and this in ...	1981	6796068
investigations on the presence of cyanophages in fresh and sea waters of romania.	investigations on the presence of cyanophages in the fresh and sea waters of romania resulted in the isolation of 31 strains. the host range of the cyanophage isolates showed some particularities as compared with classical cyanophages types. the electron optic study of the cyanophage strains grown in phormidium sp. revealed the presence of three types of virus particles, differing as regards their tail length, with a morphology similar to that of t-odd coliphages.	1981	6787794
sequence of morphological alterations in blue-green algae in the course of cyanophage infection.	electron microscopic studies were performed on the sequence of morphological alterations induced by the cyanophage pp-1 in the blue-green algae phormidium sp. and plectonema boryanum. the following phases of virus infection were made evident: virus adsorption onto the host cell; the presence of virus "ghosts", suggesting the penetration of viral dna into the cell and its multiplication in the nucleoplasm; invagination of thylakoids and formation of the "virogenic stroma"; virus maturation within ...	1981	6787795
[analysis of the cable structure of blue-green algae].	peculiarities of electrical responses under local illumination of filamentous cyanobacteria (blue-green algae). phormidium uncinatum were studied by means of extracellular electrodes. recording of electrical responses at different distances from the exposure place and comparison of these data with the results obtained on physical model of ph. uncinatum end expected response parameters computed made it possible to estimate the parameters of the cable which can serve as the object model: rc=440 c/ ...	1982	6812650
electrical nature of the taxis signal in cyanobacteria.	electrical events after a light-dark stimulus were studied in the multicellular organism phormidium uncinatum. normally, such a stimulus causes the gliding trichome to reverse direction. by directing a large light spot on the end of a batch of trichomes and then switching it off, we achieved synchronization of the trichomes, since the "head" is much more sensitive than the "tail." the abrupt disappearance of a uniform light produced a depolarization wave which initiated at the head, as registere ...	1982	6801020
[propagation of electrical potential changes in filamentous cyanobacteria].	possible energy transmission along conjugating membranes was investigated. it was found by extracellular electrodes that under local illumination of blue-green algae phormidium uncinatum the electrical current propagated along trichomes. the form and sign of the responses show that e. m. f. appears in the illumination region, which generates on the cellular membrane the potential difference with a negative charge inside the cell. the initiated transmembrane potential difference propagates along ...	1982	6803847
lateral transport of energy along the coupling membranes of cyanobacteria.	the light-induced electric potential changes brought about local illumination of trichomes of cyanobacteria phormidium uncinatum have been studied by means of extracellular electrodes. responses of several electrodes located at various distances from the illuminated area of the trichome were monitored simultaneously. they turned out to be similar in shape: a rapid increase to the maximum value was followed by a slow decay toward a nonzero residual level. the results offer strong evidence in favo ...	1982	6813322
formation of hybrid phycobilisomes by association of phycobiliproteins from nostoc and fremyella.	formation of phycobilisomes has been accomplished in vitro from isolated phycobiliprotein fractions obtained from the same blue-green alga (intrageneric) and from different blue-green algae (intergeneric). phycobilisomes, which are supra-molecular complexes of phycobiliproteins, serve as major light-harvesting antennae for photosynthesis in blue-green and red algae. intrageneric association into energetically functional phycobilisomes, previously reported to occur with nostoc sp. allophycocyanin ...	1982	16593223
direct spectrophotometric measurement of photosystem i and photosystem ii activities of photosynthetic membrane preparations from cyanophora paradoxa, phormidium laminosum, and spinach.	vesicles prepared with the french press from membranes of cyanelles of cyanophora paradoxa retain o(2) evolution activity with rates up to 500 micromoles 2,6-dichlorophenolindophenol reduced per hour per milligram chlorophyll. this activity is immediately lost when the vesicles are transferred from the sucrose-phosphate-citrate preparation buffer into dilute phosphate buffer. similar preparations from phormidium laminosum, a thermophilic cyanobacterium retain activity under such conditions. phot ...	1982	16662512
[stimulation of the natural self-purification of soil].	connected with the elaboration of the sanitary norm of cadmium in soil were performed examinations to appoint the self-purification index. this index is the highest permissible concentration of a noxious chemical substance in soil not yet injuring irreversible the process of natural self-purification. as criterions of the self-purification were selected normal and potential respiration, quantity of bacteria, actinomyceta, fungi, proteolytic, nitrifying, and cellulolytic micro-organisms, inhibiti ...	1983	6422669
characterization of photosystem ii electron acceptors in phormidium laminosum.	chlorophyll a fluorescence has been used to monitor the redox state of the primary electron acceptor of photosystem ii (ps ii) in the blue-green alga phormidium laminosum during equilibrium titrations. the shape of induction curves measured in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (dcmu) have been analyzed. the induction curves were very similar in unfractionated thylakoid membranes and ps ii particles. in both, the fast (alpha) phase was sigmoidal, and was followed by a slow ...	1983	6412632
partial characterization of six chlorophyll a-protein complexes isolated from a blue-green alga by a nondetergent method.	the chlorophyll a-protein complexes of a blue-green alga, phormidium luridum, are resolved in the absence of detergent, by the combination of a sepharose 4b column and sucrose density gradient centrifugation, into six chlorophyll a-containing zones. these six complexes are termed here as f15, f25, f35, f40, f60, and f65, according to their appearance in the sucrose density gradient after centrifugation. the absorption spectra of these six isolated complexes are reported, as well as the fluoresce ...	1983	6402982
utilization of energy stored in the form of na+ and k+ ion gradients by bacterial cells.	the hypothesis that na+ and k+ gradients have an energy storing function [v. p. skulachev (1978) febs lett. 87, 171-176] has been tested in experiments with escherichia coli, the marine bacterium vibrio harveyi, an extremely halophilic halobacterium halobium and a fresh-water cyanobacterium phormidium uncinatum from lake baikal living at an extremely low salt concentration. the capability of these microorganisms to maintain delta microh was compared using motility as a delta microh-supported fun ...	1983	6307692
accumulation of arsenic in blue-green alga, phormidium sp.	the behavior of a blue-green alga, phormidium sp., against inorganic arsenic dissolved in media was studied. the phormidium sp. was shown to have capabilities of endurance against a high concentration stress of arsenic and of accumulation of arsenic. studies on excretion of arsenic by the alga showed that there were two excretion modes, each of which had a characteristic rate constant and it could be attributed to two types of binding situations between arsenic and the tissues of the alga. the a ...	1984	6149084
hydrophobicity as an adhesion mechanism of benthic cyanobacteria.	the capacity of benthic cyanobacteria to adhere to solid substrates was examined in terms of their cell surface properties. by using a biphasic water-hydrocarbon test system, it was demonstrated that benthic cyanobacteria from divergent habitats were all hydrophobic, whereas all the planktonic cyanobacteria tested were hydrophilic. divalent cations were found more efficient than monovalent cations in effecting the expression of hydrophobicity. mechanical shearing of the cell surface, as well as ...	1984	16346453
a low potential iron-sulfur cluster bound to membranes in blue-green algae.	a new low temperature epr signal at g = 1.92 was found in photoreduced membrane fractions prepared from blue-green algae, nostoc muscorum, tolypothrix tenuis, phormidium persicinum, and anabaena variabilis. the signal also appeared when the sample was chemically reduced in the dark. judging from the spectrum, the signal was probably due to the reduced form of a membrane-bound iron-sulfur cluster, tentatively designated as cluster d. the midpoint potential of cluster d was determined to be -0.27 ...	1985	2987203
freeze-fracture analysis of thylakoid membranes and photosystem i and ii enriched fractions from phormidium laminosum.	thylakoid membranes of the thermophilic cyanobacterium phormidium laminosum have been fractionated into photosystem ii and photosystem i particles. these fractions have been characterized by their partial electron transport activities, and biochemical and spectral properties. exoplasmic fracture face and protoplasmic fracture face particles in the unfractionated thylakoid membranes were shown to correspond in size to particles in freeze-fractured photosystem ii and photosystem i fractions, respe ...	1986	3088002
bacterial enhancement of vinyl fouling by algae.	the role of bacteria in the development of algae on low-density vinyl was investigated. unidentified bacterial contaminants in unialgal stock cultures of phormidium faveolarum and pleurochloris pyrenoidosa enhanced, by 1 to 2 orders of magnitude, colonization of vinyl by these algae, as determined by epifluorescence microscopy counts and chlorophyll a in extracts of colonized vinyl. colonization by bacteria always preceded that by algae. scanning electron microscopy of the colonized phormidium-b ...	1986	16347243
crystallization of the photosystem i reaction centre.	the reaction centre of the photosynthetic membrane complex photosystem i (psi) from the thermophilic cyanobacterium phormidium laminosum was found to crystallize under a range of conditions. the crystallization method, which can occur in the presence of larger detergent molecules than those used previously for the crystallization of membrane proteins, is presented in this report. several crystal forms have been observed, and some of these show birefringence and linear dichroism. optical measurem ...	1987	16453774
characterization of macromolecular flocculants produced by phormidium sp. strain j-1 and by anabaenopsis circularis pcc 6720.	several benthic cyanobacteria were found to produce significant amounts of extracellular flocculants. the macromolecular flocculants produced by phormidium sp. strain j-1 and anabaenopsis circularis pcc 6720 were characterized. the phormidium flocculant is a sulfated heteropolysaccharide to which fatty acids and protein are bound. the polysaccharide backbone is composed of uronic acids, rhamnose, mannose, and galactose. the a. circularis flocculant is also an acidic polysaccharide containing ket ...	1987	16347442
picosecond time-resolved fluorescence from detergent-free photosystem i particles.	picosecond time-resolved fluorescence measurements have been taken on a detergent-free p700-enriched complex at room temperature isolated from the blue-green alga phormidium luridum with a chlorophyll a to reaction center ratio of 100. emission at greater than 665 nm is characterized by two exponential-decay components. a fast component, which dominates the initial decay with an average lifetime of 16 ps and 87% amplitude, is attributed to excitations in the core antenna chlorophyll-proteins, wh ...	1987	19431711
influence of cypermethrin and fenvalerate on a green alga and three cyanobacteria isolated from soil.	the effects of two pyrethroid insecticides, cypermethrin and fenvalerate, on a green alga (scenedesmus bijugatus) and three species of cyanobacteria (synechococcus elongatus, nostoc linckia, and phormidium tenue), all isolated from a black cotton soil, were studied using either cell number or chlorophyll a as toxicity criterion. all the four species were either unaffected or stimulated at 5 micrograms ml-1. of the two insecticides, cypermethrin, at 10 to 50 micrograms ml-1, inhibited s. bijugatu ...	1987	3121278
generation and isolation of cyanobacterial inside-out thylakoid vesicles.	a method has been designed to prepare inside-out thylakoid vesicles from a cyanobacterial species (phormidium laminosum). everted thylakoid vesicles could be generated by yeda press treatment after induced membrane pairing. membrane pairing was induced either by addition of high concentrations of mg2+ ions or by lowering the ph of the fragmentation media. the inside-out vesicles were isolated by aqueous polymer two-phase partition. the membrane orientation was determined by proton translocation ...	1988	3138947
coupling membranes as energy-transmitting cables. ii. cyanobacterial trichomes.	power transmission along trichomes of filamentous cyanobacteria phormidium uncinatum has been studied with the use of ethylrhodamine fluorescence as a probe for the transmembrane electric potential difference (delta psi). it is found that agents preventing the light-induced delta psi formation (photosynthetic redox chain inhibitor dibromothymoquinone) or dissipating delta psi (uncoupler tetrachlorotrifluoromethylbenzimidazole) strongly decrease the fluorescence of the ethyl-rhodamine-stained tri ...	1988	3138245
induction, isolation, and some properties of the nadph-dependent glutamate dehydrogenase from the nonheterocystous cyanobacterium phormidium laminosum.	the level of the nadph-dependent glutamate dehydrogenase activity (ec 1.4.1.4) from nitrate-grown cells of the thermophilic non-n2-fixing cyanobacterium phormidium laminosum oh-1-p.cl1 could be significantly enhanced by the presence of ammonium or nitrite, as well as by l-methionine-dl-sulfoximine and other sources of organic nitrogen (l-glu, l-gln, and methylamine). the enzyme was purified more than 4,400-fold by ultracentrifugation, ion-exchange chromatography, and affinity chromatography, and ...	1988	3139639
glutamine synthetase from a cyanobacterium, phormidium lapideum: purification, characterization, and comparison with other cyanobacterial enzymes.	glutamine synthetase has been purified to homogeneity from cell extracts of a non-n2-fixing filamentous cyanobacterium, phormidium lapideum. the subunit molecular weight of the enzyme was determined as about 59,000 by sodium dodecyl sulfate gel electrophoresis. electron micrographs of the phormidium enzyme revealed a two-layered structure of regular hexagons (12 subunits per molecule), which markedly resembles the three-dimensional polypeptide backbone structure of the salmonella typhimurium glu ...	1988	2907514
investigation of the structure of trimeric and monomeric photosystem i reaction centre complexes.	electron microscopy of monomeric and trimeric forms of the reaction centre of photosystem i from the thermophilic cyanobacterium phormidium laminosum has allowed the construction of a three-dimensional model describing the shape of the complex. the trimeric form of the photosystem i reaction centre complex was found to have a very regular shape corresponding to a rounded equilateral triangle with edges 18 nm long and a thickness of 6 nm. a distinctive chiral arrangement of the three reaction cen ...	1988	16453855
signal perception and amplification in photoresponses of cyanobacteria.	in addition to a number of other external stimuli, the gliding cyanobacterium, phormidium uncinatum, uses light as a clue to control movement in order to find and stay in a microhabitat with optimal conditions for growth and survival of the population. of the three photoresponses developed in cyanobacteria, phototaxis, photokinesis and photophobic responses, the latter are the most prominent for this task. step-down phobic responses are mediated by the photosynthetic pigments and are linked to t ...	1988	17010912
purification and properties of glutamine synthetase from the non-n2-fixing cyanobacterium phormidium laminosum.	soluble glutamine synthetase activity (l-glutamate:ammonia ligase, adp forming, ec 6.3.1.2) was purified to electrophoretic homogeneity from the filamentous non-n2-fixing cyanobacterium phormidium laminosum (oh-1-p.cl1) by using conventional purification procedures in the absence of stabilizing ligands. the pure enzyme showed a specific activity of 152 mumol of gamma-glutamylhydroxamate formed.min-1 (transferase activity), which corresponded to 4.4 mumol of pi released.min-1 (biosynthetic activi ...	1989	2563365
gene sequence for the 9 kda component of photosystem ii from the cyanobacterium phormidium laminosum indicates similarities between cyanobacterial and other leader sequences.	a 9 kda polypeptide which is loosely attached to the inner surface of the thylakoid membrane and is important for the oxygen-evolving activity of photosystem ii in the thermophilic cyanobacterium phormidium laminosum has been purified, a partial amino acid sequence obtained and its gene cloned and sequenced. the derived amino acid sequence indicates that the 9 kda polypeptide is initially synthesised with an n-terminal leader sequence of 44 amino acids to direct it across the thylakoid membrane. ...	1989	2501648
ordered arrays of the photosystem i reaction centre after reconstitution: projections and surface reliefs of the complex at 2 nm resolution.	we present an electron microscopical analysis of the photosystem i reaction centre, the membrane complex involved in the second light-driven step of photosynthetic electron transfer in plants and cyanobacteria. to this end, ordered two-dimensional arrays were reconstituted from detergent solubilized photosystem i reaction centres and phospholipids, and studied by electron microscopy and digital image processing. small (p1) and large (p3) hexagonal lattices obtained with reaction centres of the t ...	1990	2120036
dismutation of hydroxylamine to ammonia and nitrite by a novel, membrane-bound enzyme from the cyanobacterium phormidium uncinatum.	extracts from ammonium-grown phototrophic cultures of phormidium uncinatum exhibited a catalytic and stoichiometric formation of nitrite and ammonia from hydrogen peroxide and hydroxylamine. this reaction was due to a novel enzyme (referred to as hydroxylamine dismutase), which was bound to the heavier thylakoid membranes. the enzyme was solubilized from the membranes by detergent treatment and further purified by ion-exchange chromatography. on the basis of inhibitor studies, the involvement of ...	1990	2121280
the reaction specificities of the pea and a cyanobacterial thylakoid processing peptidase are similar but not identical.	the thylakoid processing peptidase from the cyanobacterium phormidium laminosum has been extracted from thylakoid membranes by solubilization with triton x-100. its reaction specificity has been compared with the analogous pea peptidase by processing in vitro of radiolabelled wheat and p. laminosum thylakoid lumenal precursor polypeptides. the cyanobacterial polypeptide is processed to the mature size through an intermediate by the p. laminosum peptidase, but to a polypeptide that has a slightly ...	1990	2121534
composition of the ferredoxin-nitrite reductase from the cyanobacterium phormidium laminosum.		1990	2125945
distribution of phototrophic microbes in the flat laminated microbial mat at laguna figueroa, baja california, mexico.	the microbial mat community in the saltmarsh/evaporate flat interface at laguna figueroa involved in the deposition of laminated sediments was investigated. pigment analysis, light microscopy and transmission electron microscopy were used to determine the relative abundance and distribution of phototrophic species. the community is vertically stratified into four distinct phototrophic populations. the layering could be distinguished by pigment and species composition. the two layers closest to t ...	1990	2108737
purification and some properties of the nitrite reductase from the cyanobacterium phormidium laminosum.	assimilatory ferredoxin-nitrite reductase (ec 1.7.7.1, ammonia: ferredoxin oxidoreductase) has been purified 5300-fold with a specific activity of 625 units/mg protein from the filamentous non-heterocystous cyanobacterium phormidium laminosum. the enzyme was soluble and consisted of a single polypeptidic chain of 54 kda. it catalyzed the reduction of nitrite to ammonia using ferredoxin or flavodoxin as electron donor. methyl and benzyl viologens were also effective as electron donors but neither ...	1990	2119228
power transmission along biological membranes.	hypothesis on long-distance power transmission along extended energy-transducing membranes (skulachev, 1969, 1971, 1980), has been experimentally proven in four different systems, namely, (i) trichomes of filamentous cyanobacterium phormidium uncinatum; (ii) filamentous mitochondria and mitochondrial network in fibroblasts; (iii) clusters of roundish heart muscle mitochondria interconnected with mitochondrial junctions; (iv) mixed animal cell cultures interconnected with gap junctions. in all ca ...	1990	2111408
an autolytic substance in a freshwater cyanobacterium phormidium tenue.	an autolytic substance in an axenic cyanobacterium, phormidium tenue, was identified as a mixture of fatty acids, by use of cultured cells in the laboratory. among them, linoleic acid and linolenic acid were potent growth inhibitors.	1990	2112049
studies on a toxin produced by the cyanobacterium phormidium persicinum.		1991	1794548
interactive image analysis system to determine the motility and velocity of cyanobacterial filaments.	an interactive image analysis system has been developed to analyse and quantify the percentage of motile filaments and the individual linear velocities of organisms. the technique is based on the "difference" image between two digitized images taken from a time-lapse video recording 80 s apart which is overlaid on the first image. the bright lines in the difference image represent the paths along which the filaments have moved and are measured using a crosshair cursor controlled by the mouse. ev ...	1991	1908871
carotenoid composition in the cyanobacterium phormidium laminosum. effect of nitrogen starvation.	when pigments of the non-n2-fixing cyanobacterium phormidium laminosum were carefully extracted and analyzed in a completely o2-free atmosphere, by either high performance liquid chromatography (hplc) or thin layer chromatography (tlc), the presence of only two carotenoids (namely, beta-carotene and nostoxanthin) was detected. however, exposure of pigments to an air atmosphere during their manipulation led to the rapid appearance in the organic extracts of at least three additional carotenoids ( ...	1991	1903716
studies on glycolipids. iii. glyceroglycolipids from an axenically cultured cyanobacterium, phormidium tenue.	seven new monogalactosyl diacylglycerols (1-7) and six new digalactosyl diacylglycerols (11-16) were isolated from an axenically cultured cyanobacterium, p. tenue. their structures were elucidated on the basis of physicochemical evidence and the results of enzymatic hydrolysis using a lipase (from rhizopus arrhizus). comparison of antialgal activity for p. tenue between monogalactosyl diacylglycerols (1-8) and digalactosyl diacylglycerols (11-19) revealed that the former showed more potent activ ...	1991	1804541
modulation of fibroblast motility by a cytosolic extract of cyanobacteria.	proliferation and migratory behavior of l929 murine fibroblasts were shown to be modified in the presence of a cytosolic extract of phormidium sp. (cyanobacteria). the addition of phormidium extract to the growth medium (dulbecco's modified eagle's medium) supplemented with 0.5% newborn calf serum increased cell proliferation. the effect was shown to be cell line specific. a quantitative analysis performed according to de laat, tertoolen, and bluemink (1981, eur. j. cell biol., 23, 273-279), sho ...	1991	1910290
accumulation of trehalose and sucrose in cyanobacteria exposed to matric water stress.	the drought-resistant cyanobacteria phormidium autumnale, strain lpp(4), and a chroococcidiopsis sp. accumulated trehalose, sucrose, and both trehalose and sucrose, respectively, in response to matric water stress. accumulated sugar concentrations reached values of up to 6.2 mug of trehalose per mug of chlorophyll in p. autumnale, 6.9 mug of sucrose per mug of chlorophyll in lpp(4), and 4.1 mug of sucrose and 3.2 mug of trehalose per mug of chlorophyll in the chroococcidiopsis sp. the same sugar ...	1991	16348431
occurrence of a photosystem ii polypeptide in non-photosynthetic membranes of cyanobacteria.	cytoplasmic and thylakoid membranes have been purified from the cyanobacteria anacystis nidulans r2 and phormidium laminosum by sucrose density gradient centrifugation. probing of western blots of proteins from these purified membrane fractions with antibodies directed against the 33 kda polypeptide of photosystem ii from pea indicates that this protein is present in both the thylakoid and cytoplasmic membranes, rather than just the thylakoid membranes. this has been confirmed by immunogold labe ...	1992	1630319
isolation and identification of the restriction endonuclease ptai from phormidium tadzschicicum, an isoschizomer of bspmii.		1992	1480496
stoichiometric association of extrinsic cytochrome c550 and 12 kda protein with a highly purified oxygen-evolving photosystem ii core complex from synechococcus vulcanus.	a highly purified, native photosystem ii (ps ii) core complex was isolated from thylakoids of synechococcus vulcanus, a thermophilic cyanobacterium by lauryldimethylamine n-oxide (ldao) and dodecyl beta-d-maltoside solubilization. this native ps ii core complex contained, in addition to the proteins that have been well characterized in the core complex previously purified by ldao and triton x-100, two more extrinsic proteins with apparent molecular weights of 17 and 12 kda. these two proteins we ...	1992	1314738
generation of lysoglyceroglycolipids in the cyanobacterium, phormidium tenue.	two kinds of lysoglycolipids, monogalactosyl 1-monoacylglycerol and digalactosyl 1-monoacylglycerol were generated in the cyanobacterium, phormidium tenue, when it was stored at -20 degrees for more than 1 month. by comparison of the compositions of fatty acid residues between monogalactosyl 1-monoacylglycerol and monogalactosyl diacylglycerol, digalactosyl 1-monoacylglycerol and digalactosyl diacylglycerol, respectively, the 1-monoacylgalactolipids were presumed to be formed by regioselective d ...	1992	1368418
assembly of 2-d membrane protein crystals: dynamics, crystal order, and fidelity of structure analysis by electron microscopy.	membrane protein reconstitution into two-dimensional (2-d) ordered arrays is described. the assembly of 2-d crystals may be modeled as a two-step process: the membrane protein is first integrated in the lipid bilayer and then crystallized by removal of excess detergent or lipid and/or by precipitating agents. lipid-detergent, protein-detergent, and lipid-protein interactions are critical during the first step, while lipid-protein and protein-protein interactions dominate events in the second ste ...	1992	1296757
pami and pamii restriction endonucleases from phormidium ambiguum.		1992	1741304
auto-growth inhibitory substance from the fresh-water cyanobacterium phormidium tenue.	an extract of the cyanobacterium p. tenue showed a significant inhibitory effect on its own growth. bioassay-directed fractionation has led to the identification of the auto-growth inhibitory substance as a mixture of fatty acids. unsaturated fatty acids such as linoleic and linolenic acids appear to be predominantly responsible for the auto-growth inhibitory effect.	1993	8281581
characterization of a small cryptic plasmid, ppf1, from phormidium foveolarum and vector construction.	the 1509 bp cryptic plasmid, ppf1, from phormidium foveolarum, a strain of filamentous cyanobacteria of the lpp group, was completely sequenced. the ppf1 nucleotide sequence had 97.8% overall similarity with that of a small plasmid from plectonema boryanum. the structural organization of ppf1 and vector construction are discussed.	1993	7764277