Publications

isolation and functional reconstitution of a phosphate binding protein of the cyanobacterium anacystis nidulans induced during phosphate-limited growth.	adaptation of the blue-green algae anacystis nidulans to phosphate-deficient growth leads to the expression of two membrane proteins, which appear as major constituents after separation by gel electrophoresis. one of these proteins, referred to as high affinity phosphate binding protein, has been isolated and its function reconstituted in liposomes. partial sequencing showed no significant homologies to other proteins. the binding capacity of the proteoliposomes could be inhibited by arsenate bu ...	1994	8119882
phylogenetic spectrum of fungi that are pathogenic to humans.	recent phylogenetic studies based on ribosomal rna sequences have confirmed that the organisms traditionally treated as fungi include those that have evolved from several different lines (multiphyletic organisms), as has been suspected. even organisms causing disease in humans represent at least two evolutional lines. pythium insidiosum and prototheca species are both believed to have evolved from one line, while the rest of the pathogens have evolved from another line. p. insidiosum is more clo ...	1994	7948565
[blue-green algae as a cause of human disease].	blue-green algae can cause significant public health problems. there is an abundance of scientific literature on their effects, but much of it either reports laboratory studies of toxicological effects or discusses practical problems affecting water supply. there are many reports of poisonings of farm animals and wildlife, and a number of reports of adverse health effects in humans, but the effects of blue-green algae on human health do not seem to have attracted serious attention amongst practi ...	1994	8079249
probable role of blue-green algae in maintaining endemicity and seasonality of cholera in bangladesh: a hypothesis.		1994	7751564
rapid growth of lymnaea viridis, the intermediate host of fasciola hepatica, under laboratory conditions.	reported in this communication is a unusually rapid growth of lymnaea viridis, the intermediate host of fasciola hepatica, maintained in the laboratory for experimental purposes. when the snails were fed on blue-green algae at about 20 degrees c, they attained a shell length of 12 mm in 37 days from the date of hatching. the snails began laying eggs from 18 to 24 days following hatching.	1994	8171836
antimutagenic properties of fresh-water blue-green algae.	the antimutagenic properties of whole fresh-water blue-green algae aphanisomenon flos-aquae, marketed under the commercial name "alpha sun" were tested using the ames test. simultaneous addition of both algae and nitrovin (a mutagen) to the test medium did not reduce the mutagenic activity. on the other hand, addition of freeze-dried blue-green algae to the test medium 2-24 h before the application of mutagen reduced its mutagenic activity.	1994	7729766
elevated co2: impact on diurnal patterns of photosynthesis in natural microbial ecosystems.	algae, including blue-green algae (cyanobacteria), are the major source of fixed carbon in many aquatic ecosystems. previous work has shown that photosynthetic carbon fixation is often enhanced in the presence of additional carbon dioxide (co2). this study was undertaken to determine if this co2 fertilization effect extended to microbial mats, and, if so, at what times during the day might the addition of co2 affect carbon fixation. four microbial mats from diverse environments were selected, in ...	1994	11538022
effects of pulp mill chlorate on baltic sea algae.	the long-term effects of pulp mill chlorate on different algal species of the baltic sea were studied in land-based model ecosystems simulating the littoral zone. brown algae (phaeophyta) exhibited an extraordinarily high sensitivity to chlorate and pulp mill effluents containing chlorate. all brown algal species ceased growth or showed major signs of toxicity at all concentrations tested, down to microgram per litre levels. ec50 levels for growth of fucus vesiculosus were about 80-100 microg cl ...	1994	15091680
fluorescence polarization of triple-chromophore complexes with energy transfer.	the formula for the determination of a fluorescence polarization degree is derived for triple-chromophore complexes with energy transfer: p = (3b - 1 + 2a)/(3 + b + 4a). in this formula b = q(12) cos(2)(?(12)) + q(13) cos(2)(?(13)) + q(23) cos(2)(?(23)) and parameters a and q(ij) are dependent on the kinetic parameters of energy exchange and the chromophore spectroscopic parameters. the angle ?ij is the angle between the transition dipole moments of the i and j chromophores. the formula was test ...	1994	20941161
use of freshwater plants for phytotoxicity testing: a review.	phytotoxicity data for aquatic plants have served a relatively minor role in regulatory decisions concerning the environmental hazard of most potential contaminants. a variety of phytotoxicity tests have been conducted with freshwater green algae, duckweed, blue-green algae, diatoms and rooted macrophytes (whole plants and seeds). several test methods have been standardized for microalgae which are used primarily with chemicals, effluents, contaminated sediment elutriates and hazardous waste lea ...	1995	15091582
the first reported outbreak of diarrheal illness associated with cyclospora in the united states.	to investigate and characterize the epidemiology of a diarrheal outbreak associated with a potentially new pathogen, cyclospora species (previously referred to as cyanobacteria [blue-green algae]-like bodies).	1995	7639439
enzymatic analysis of liver samples from rainbow trout for diagnosis of blue-green algae-induced toxicosis.	microcystin and related toxic peptides produced by cyanobacteria (blue-green algae) are potent and selective inhibitors of protein phosphatases 1 and 2a. we adapted existing enzymatic techniques to analyze the liver of rainbow trout after oral administration of hepatotoxic cyanobacteria. liver tissue was removed 3 and 12 hours after treatment, and phosphatase activity was determined in liver extracts, using a specific phosphoprotein substrate. in all samples from fish exposed to toxic cyanobacte ...	1995	8533985
cyanobacterial (blue-green algae) poisoning of livestock in the western cape province of south africa.	three outbreaks of cyanobacterial (blue-green algae) poisoning involving cattle and sheep are described. in 2 of these acute mortality was followed by photodermatitis in some of the surviving animals. in all 3 outbreaks the hepatotoxicity of the water collected from the dams where the animals had been drinking was confirmed following the intraperitoneal administration to mice. nodularia spumigena was the dominant cyanobacterium in the first 2 outbreaks, and microcystis aeruginosa in the third. t ...	1995	8691420
[cyanobacteria, their toxins and health risks].	cyanobacteria (blue-green algae) commonly occur in fresh and brackish water where they produce blooms under certain environmental and climatic conditions. since some species produce neurotoxins, hepatotoxins, cytotoxins, and endotoxins, blooms can be hazardous for animal and human health. several cases of human cyanobacterial poisoning have been documented, but accurate assessment of the risk is difficult for lack of knowledge concerning exposure levels and the incidence of this kind of poisonin ...	1995	8830224
reversible effects of okadaic acid and microcystin-lr on the atp-dependent interaction between actin and myosin.	okadaic acid, a toxin from black sponge, and microcystin-lr, a toxin from blue-green algae, were found to stimulate and inhibit, respectively, the actin-activated atpase activity of skeletal muscle myosin. these effects were confirmed by monitoring the sliding movement of actin-filaments on myosin. this technique also enabled us to demonstrate the reversibility of these effects, a property that is essential for their use as a pharmacological tool for the analysis of the mechanochemical character ...	1995	7629015
[interaction of 2fe-2s-ferredoxins from plants and adrenal cortex with detergents].	the interactions of 2fe-2s ferredoxins from bovine adrenal cortex, blue-green algae and leaves of three plant species with some positively and negatively charged as well as with uncharged detergents, have been studied. these interactions generally resulted in the destruction of active centers of ferredoxins represented by the 2fe-2s cluster. the role of oxidants (oxygen and potassium ferricyanide) in cluster destruction by detergents has been established. the opposite sensitivity of plant and an ...	1995	7578561
biotransformation of benzo[a]pyrene and other polycyclic aromatic hydrocarbons and heterocyclic analogs by several green algae and other algal species under gold and white light.	this laboratory has shown that the metabolism of benzo[a]pyrene (bap), a carcinogenic polycyclic aromatic hydrocarbon (pah), by a freshwater green alga, selenastrum capricornutum, under gold light proceeds through a dioxygenase pathway with subsequent conjugation and excretion. this study was undertaken to determine: (1) the effects of different light sources on the enzymatic or photochemical processes involved in the biotransformation of bap over a dose range of 5-1200 mg/l; (2) the phototoxici ...	1995	7606812
isolation of individual amino acids from various microbiological sources using reversed-phase high-performance liquid chromatography.	a new method for the preparative isolation of individual amino acids on a milligram scale based on reversed-phase high-performance liquid chromatography (rp-hplc) after pre-column derivatization with carbobenzoxychloride (z-cl) has been developed. the chromatographic procedure was tested by the investigation of jack bean urease hydrolysate. the method has been applied to the preparative separation of z-amino acids (from 10 up to 16) obtained from protein hydrolysates of various sources (green mi ...	1995	7795801
colonization and bionomics of forcipomyia taiwana (diptera:ceratopogonidae) in the laboratory.	an improvement in colonizing the biting midge forcipomyia taiwana (shiraki) was achieved by a new technique that facilitated the rearing of the midges and induced them to mate in the laboratory. at temperature of 15, 20, 25, and 30 degrees c, the development duration of the egg, 4 larval instars, and pupa decreased as temperature increased. among 7 different diets, the blue green algae, anabaena sp.ch3, was the best food for rearing the midges. when the larvae were fed on the blue green algae at ...	1996	8667393
the substrate specificity of tocopherol cyclase.	the substrate specificity of the enzyme tocopherol cyclase from the blue-green algae anabaena variabilis (cyanobacteria) was investigated with 11 substrate analogues revealing the significance of three major recognition sites: (i) the oh group at c(1) of the hydroquinone, (ii) the (e) configuration of the double bond, and (iii) the length of the lipophilic side chain. experiments with two affinity matrices suggest that substrates approach the enzyme's active site with the hydrophobic tail.	1996	8831985
the notion of the cambrian pananimalia genome.	the toil by photosynthesizing cyanobacteria and blue-green algae of nearly three billion years appeared to have finally resulted in the sufficient accumulation of molecular oxygen. so, the stage was set for the emergence, at the ocean bottom, of diverse animals that were consumers of molecular oxygen. it now appears that this cambrian explosion, during which nearly all the extant animal phyla have emerged, was of an astonishingly short duration, lasting only 6-10 million years. inasmuch as only ...	1996	8710894
cyclic peptides and depsipeptides from cyanobacteria: a review.	an elaborate array of structurally-novel and biologically-active cyclic peptides and depsipeptides are found in blue-green algae (cyanobacteria). several of these compounds possess structures that are similar to those of natural products from marine invertebrates. most of these cyclic peptides and depsipeptides, such as the microcystins and the lyngbyatoxins, will probably only be useful as biochemical research tools. a few, however, have the potential for development into useful commercial prod ...	1996	8730577
characterization of anopheles darlingi (diptera: culicidae) larval habitats in belize, central america.	surveys for larvae of anopheles darlingi root were conducted in april, may, and august 1994 in riverine habitats of central belize (cayo and belize districts). an. darlingi was present during both the dry and wet seasons. larvae were encountered most frequently in patches of floating debris along river margins. the floating mats were often formed by bamboo hanging over the banks and dense submersed bamboo roots. larvae were found less frequently in lake margins, small lagoons, and ground pools w ...	1996	8742522
aplysiatoxin and debromoaplysiatoxin as the causative agents of a red alga gracilaria coronopifolia poisoning in hawaii.	the causative toxins of a red alga gracilaria coronopifolia poisonings in hawaii, which broke out in succession in september of 1994, were studied. two major toxins were isolated from both extracts of the two original algal samples which caused separate poisonings. by spectroscopic method, these toxins were shown to be completely identical with aplysiatoxin and debromoaplysiatoxin which have previously been obtained from the sea hare and also from blue green algae. the human symptoms and the amo ...	1996	8843576
biliary excretion of biochemically active cyanobacteria (blue-green algae) hepatotoxins in fish.	previous reports demonstrated that microcystin and related cyanobacteria polypeptides are rapidly cleared from plasma and accumulate in liver tissue. in the present study, we have used their ability to inhibit protein phosphatases to show that these cyanobacteria hepatotoxins are excreted into the bile of experimentally poisoned rainbow trout. at various times after oral administration of hepatotoxic microcystis aeruginosa, bile samples were analysed for microcystin content by methanol extractio ...	1996	8571383
structure-function relationships in the dual-function photosynthetic-respiratory electron-transport assembly of cyanobacteria (blue-green algae).		1996	8878835
separation of toxic peptides (microcystins) in capillary electrophoresis, with the aid of organic mobile phase modifiers.	a capillary electrophoretic (ce) method incorporating sodium dodecyl sulphate (sds)-organic modifier solvents in the ce buffer was developed for the detection of toxic cyclic heptapeptide toxins (microcystins) produced by blue-green algae (cyanobacteria). the applicability of these run buffers for the analysis of microcystins was evaluated and optimum conditions for separation were determined. the migration times, elution order and selectivity of the toxic peptides were influenced by modifying t ...	1996	8921598
anopheles albimanus (diptera: culicidae) and cyanobacteria: an example of larval habitat selection.	northern belize has extensive herbaceous wetlands. those dominated by sparse emergent macrophytes, rushes (eleocharis spp.) and sawgrass (cladium jamaicense crantz), often develop floating mats of cyanobacteria (blue-green algae). these mats provide suitable habitat for larvae of the malaria transmitting mosquito anopheles albimanus wiedemann. presence/absence of a. albimanus larvae and cyanobacterial mats was assessed in marshes located throughout northern belize. of the 21 marshes examined dur ...	1996	11540613
observations on the mechanisms of attachment of some marine fouling blue-green algae.	using scanning electron microscopy (sem), differential interference contrast microscopy (dicm) and cytochemical staining techniques, preliminary observations have been made on the mechanisms of attachment of some common, marine, benthic fouling blue-green algae ("cyanobacteria") isolated into culture from various toxic and non-toxic surfaces in langstone harbour, south coast of england. blue-green algae investigated included species of calothrix, dermocarpa, plectonema, phormidium and xenococcus ...	1996	22115109
the reason for as well as the consequence of the cambrian explosion in animal evolution.	the first 1 billion years of our 4.5-billion-year-old planet were extremely violent, characterized by constant meteorite bombardment. therefore, it is with a great surprise that we note that cellular life flourished 3.5 billion years ago. it appears that the cellular life came into being as soon as the earth's environment became hospitable. because the main ingredient of the archean sea was sodium bicarbonate, neither archeobacteria nor eubacteria but rather photosynthesizing organisms dominated ...	1997	9071008
measurement of coherent debye-waller factor in in vivo deuterated c-phycocyanin by inelastic neutron scattering.	quasielastic neutron scattering measurements of dry and 35% d2o hydrated amorphous protein powder of c-phycocyanin were made as a function of temperature ranging from 313k down to 100k. the protein is grown from blue-green algae cultured in d2o and is deuterated up to 99%. the scattering is thus dominated by coherent scattering. within the best energy resolution of the time-of-flight instrument, which is 28 muev fwhm, the scattering appears entirely elastic. for this reason we are able to extrac ...	1997	9083683
reclamation with cyanobacteria: toxic effect of mercury contaminated waste soil on biochemical variables.	during an attempt to decrease the toxicity of industrial waste (soil) from a chloralkali factory by blue-green algae, the effect of the waste soil mixed in varying proportions with garden soil, on biochemical variables was studied. the nucleic acid, protein and free amino acid content of the algae decreased significantly with increasing time and waste soil concentration. the algae accumulated a substantial amount of mercury from the medium depending on the duration of algal growth and waste soil ...	1997	9693887
anatoxin-a in irish freshwater and cyanobacteria, determined using a new fluorimetric liquid chromatographic method.	a new sensitive high-performance liquid chromatographic (hplc) method was used to determine anatoxin-a in freshwater, following blooms of cyanobacteria (blue-green algae). anatoxin-a was converted into a highly fluorescent derivative using 4-fluoro-7-nitro-2,1,3-benzoxadiazole and hplc analysis gave good linear calibrations even at low concentration ranges (1-10 micrograms/liter, r = 0.997). the detection limit for anatoxin-a was 0.02 ng/ml, and this new hplc method should prove useful for the r ...	1997	9241789
a multitype branching process model for blue-green algae.	in this article, a multitype branching process is proposed for the behavior of populations of linear clusters of cells. the main results concern the asymptotic cluster size distribution.	1997	9309931
health effects of exposure to cyanobacteria (blue-green algae) during recreational water-related activities.	the aim of this study was to investigate effects on health of exposure to cyanobacteria as a result of recreational water activities. participants, who were aged six years and over, were interviewed at water recreation sites in south australia, new south wales and victoria on selected sundays during january and february 1995. telephone follow-up was conducted two and seven days later to record any subsequent diarrhoea, vomiting, flu-like symptoms, skin rashes, mouth ulcers, fevers and eye or ear ...	1997	9470258
detection of an anatoxin-a(s)-like anticholinesterase in natural blooms and cultures of cyanobacteria/blue-green algae from danish lakes and in the stomach contents of poisoned birds.	ten natural bloom samples of cyanobacteria from the danish lakes knud sø (5), ravn sø (4), and salten langsø (1) collected during 1993-1995 were assayed for toxicity by mouse bioassay, for acetylcholinesterase inhibiting activity by a colorimetric method, and for microcystins by enzyme-linked immunosorbent assay. in the mouse bioassay, seven samples were neurotoxic, two were non-toxic and one gave a protracted toxic response. one of the non-toxic and the single protracted toxic sample both conta ...	1997	9241784
detection of toxin-producing cyanobacteria by use of paramagnetic beads for cell concentration and dna purification.	early detection of water blooms caused by potential toxin-producing cyanobacteria is important in environmental monitoring. we present a new nucleic acid-based method for detection of cyanobacteria in water that utilizes the same paramagnetic solid phase (beads) for both bacterial cell concentration and subsequent dna purification. in the cell concentration step, the beads were attracted to a magnet after cell adsorption (in an alcohol- and salt-containing solution), and the supernatant was remo ...	1998	9435059
further studies on anti-inflammatory activity of phycocyanin in some animal models of inflammation.	to examine the effects of c-phycocyanin, a pigment found in blue-green algae which acts as an antioxidant in vitro and in vivo, in different animal models of inflammation.	1998	9754867
antioxidant and anti-inflammatory properties of c-phycocyanin from blue-green algae.	phycocyanin is a pigment found in blue-green algae which contains open chain tetrapyrroles with possible scavenging properties. we have studied its antioxidant properties.	1998	9495584
blue-green algae toxicosis in cattle.	twenty-four of 175 heifers died after ingesting water from a stock pond containing blue-green algae (genus microcystis) in southern colorado. affected cattle were found dead or had signs of nervousness, and were recumbent, weak, anorectic, and hypersensitive to noise when first examined. all cattle died within 3 days after the onset of signs. at necropsy, the rumen contained blue-green algae, and the liver was larger than normal, friable, and dark red. the most important histologic lesion was he ...	1998	9838962
the solution nmr structure of a blue-green algae hepatotoxin, microcystin-rr--a comparison with the structure of microcystin-lr.	the microcystin-rr structures are compared with the structures of microcystin-lr in solution as well as in the crystal structure of the complex with protein phosphatase. the gross structures of the two peptides are similar, but with a more accentuated and compact saddle structure for microcystin-rr. the structural differences affect the hydrogen-bond pattern in the peptides and the location of the side chain of n-methyldehydroalanine, both of which are important for the ability of the peptide to ...	1998	9874194
microcystin toxicosis in cattle due to overgrowth of blue-green algae.	toxicosis due to microcystin-containing blue-green algae has been sporadically reported in a variety of animal species. most reports of intoxication involve algal blooms during periods of warm temperatures and abundant sunshine in the spring or early summer. a case of blue-green algae toxicosis with lesions attributable to toxins from microcystis aeruginosa is described in 4 cattle from southern georgia during november. the case was unusual in that characteristic hepatic necrosis was accompanied ...	1998	9467204
photocatalytic degradation of cyanobacterial microcystin toxins in water.	the microcystins are hepatotoxins produced by a number of cyanobacterial species (blue green algae) in fresh water systems. the increasing eutrophication of natural waters has led to an increase in the incidence of algal blooms and the consequent increased risk of microcystin contamination of water resources. the removal of microcystins lr, yr and ya from contaminated water was investigated using an experimental laboratory-scale photocatalytic 'falling film' reactor in which an oxygen purge, uv ...	1998	9839673
cryptophycin 1 cellular levels and effects in vitro using l1210 cells.	cryptophycin 1 is a natural product that was initially isolated from blue-green algae which has shown potent broad spectrum antitumor activity in preclinical in vitro and in vivo models. the drug strongly binds to tubulin and disrupts microtubule assembly for more than 24 hours after its removal. we evaluated cell survival, intracellular levels and inhibition of macromolecular synthesis in l1210 cells following exposure to cryptophycin 1 in vitro. cell survival was strongly inhibited following d ...	1998	10360599
fatal microcystin intoxication in haemodialysis unit in caruaru, brazil.	after a drought in february, 1996, all 126 patients in a haemodialysis unit in caruaru, north-east brazil, developed signs and symptoms of acute neurotoxicity and subacute hepatotoxicity following the use of water from a lake with massive growth of cyanobacteria (blue-green algae). 60 patients died.	1998	9800741
studies on oxidative damage induced by cyanobacteria extract in primary cultured rat hepatocytes.	contamination of water by cyanobacteria (blue-green algae) is a serious health problem around the world, largely due to the toxic effects of microcystins, a group of potent hepatotoxins. however, the mechanisms responsible for the cytotoxicity of microcystins have not been fully elucidated. in the present study, oxidative damage caused by lyophilized freshwater cyanobacteria extract was evaluated on primary cultured rat hepatocytes. a time- and dose-dependent increase of lactate dehydrogenase (l ...	1998	9630440
larvicidal properties of the cyanobacterium westiellopsis sp. (blue-green algae) against mosquito vectors.		1999	10492746
separation and identification of hydrocarbons and other volatile compounds from cultured blue-green alga nostoc sp. by gas chromatography-mass spectrometry using serially coupled capillary columns with consecutive nonpolar and semipolar stationary phases.	the complex hydrocarbons and volatile compounds produced by cultured blue-green alga nostoc sp. were separated by serially coupled capillary columns with consecutive nonpolar and semipolar stationary phases. more than 130 metabolites including, cyclohexane, cyclopentane, normal saturated hydrocarbons (c7-c30), fatty acids and benzene derivatives were identified by gc-ms. the most abundant family of hydrocarbons identified were derivatives of cyclohexane (41) and cyclopentane (11). most of these ...	1999	10596980
isolation and characterization of a mannan-binding lectin from the freshwater cyanobacterium (blue-green algae) microcystis viridis.	microcystis viridis nies-102 strain, a unicellular freshwater bloom-forming cyanobacterium, showed transient hemagglutinating activity in laboratory culture during stationary phase under nonaeration conditions. however, the hemagglutinating activity which was inhibited with yeast mannan could not be observed during culture with aeration. a mannan-binding lectin named mvl was isolated with the assay of the hemagglutinating activity against rabbit erythrocytes from the cyanobacterium by successive ...	1999	10600484
the insecticidal activity of cyanobacteria against four insects, two of medical importance and two agricultural pests with reference to the action on albino mice.	acute lethal toxicity of cyanobacteria (blue-green algae) was investigated against 3rd larval stages of musca domestica, and culex pipiens, and 4th larval stages of spodoptera littoralis and agrotis ipsilon. the ld50s were 1.94, 2.33, 7.59 and 9.10 microg for m. domestica, c. pipiens, s. littoralis and a. ipsilon respectively. the slope functions were 4,045 +/- 0.332 (m. domestica), 4.122 +/- 0.336 (c. pipiens), 4.15 +/- 0.35 (s. littoralis) and 3.72 +/- 0.34 (a. ipsilon). these ld50s markedly a ...	1999	12561932
using an enzyme linked immunosorbent assay (elisa) and a protein phosphatase inhibition assay (ppia) for the detection of microcystins and nodularins.	cyanotoxins produced by cyanobacteria (blue-green algae) include potent neurotoxins and hepatotoxins. the hepatotoxins include cyclic peptide microcystins and nodularins plus the alkaloid cylindrospermopsins. among the cyanotoxins the microcystins have proven to be the most widespread, and are most often implicated in animal and human poisonings. this paper presents a practical guide to two widely used methods for detecting and quantifying microcystins and nodularins in environmental samples-the ...	1999	11122533
identification of an atp-binding cassette transporter involved in bicarbonate uptake in the cyanobacterium synechococcus sp. strain pcc 7942.	exposure of cells of cyanobacteria (blue-green algae) grown under high-co(2) conditions to inorganic c-limitation induces transcription of particular genes and expression of high-affinity co(2) and hco(3)(-) transport systems. among the low-co(2)-inducible transcription units of synechococcus sp. strain pcc 7942 is the cmpabcd operon, encoding an atp-binding cassette transporter similar to the nitrate/nitrite transporter of the same cyanobacterium. a nitrogen-regulated promoter was used to selec ...	1999	10557362
catalase-peroxidases in cyanobacteria--similarities and differences to ascorbate peroxidases.	cyanobacteria (blue-green algae) are oxygenic phototrophic bacteria carrying out plant-type photosynthesis. the only hydrogen peroxide scavenging enzymes in at least two unicellular species have been demonstrated to be bifunctional cytosolic catalase-peroxidases (catpxs) having considerable homology at the active site with plant ascorbate peroxidases (apxs). in this paper we examined optical and kinetic properties of catpxs from the cyanobacteria anacystis nidulans and synechocystis pcc 6803 and ...	1999	10694066
genotoxicity of microcystic cyanobacteria extract of a water source in china.	the water pollution of toxic cyanobacteria (blue-green algae) is a worldwide problem and worsens with industrialization. microcystins are potent cyclic heptapeptidic hepatotoxins produced mainly by microcystis aeruginosa, and their hepatotoxicity has been well-documented. in contrast, information on the genotoxic effects of microcystins is relatively scarce. in our present study, the genotoxicity of microcystic cyanobacteria extract (mce) of a water source in china was studied using salmonella t ...	1999	10393275
selenium bioaccumulation by the water boatman trichocorixa reticulata (guerin-meneville).	the input of selenium from subsurface agricultural drainage into surface water systems can result in the accumulation of toxic concentrations of selenium in aquatic food chains. elevated selenium concentrations in aquatic systems is a significant environmental problem in many areas of the united states. a laboratory investigation was conducted to determine the dominant route of selenium bioaccumulation by the corixid trichocorixa reticulata, an important food chain organism. the roles of waterbo ...	1999	10047597
the toxicity of cyanobacterial toxins in the mouse: i microcystin-lr.	blooms of cyanobacteria or blue-green algae are known to have caused poisoning in fish, waterfowl, animals and man. one of the toxins responsible for this is the hepatotoxin microcystin-lr which has been found to occur in blooms present intermittently in sources used for domestic water supplies. three sets of experiments were undertaken to investigate the acute toxicity of microcystin-lr in mice and rats by the oral and intraperitoneal routes, the potential for effects on foetal development in t ...	1999	10215106
cyanobacterial (blue-green algae) contamination in drinking water and perinatal outcomes.	the aim of this ecological study was to examine the relationship between potential cyanobacterial exposure through drinking water during pregnancy and birth outcomes.	1999	10330729
the first evidence of paralytic shellfish toxins in the fresh water cyanobacterium cylindrospermopsis raciborskii, isolated from brazil.	the blooms of toxic cyanobacteria (blue-green algae) are causing problems in many countries. during a screening of toxic freshwater cyanobacteria in brazil, three strains isolated from the state of sao paulo were found toxic by the mouse bioassay. they all were identified as cylindrospermopsis raciborskii by a close morphological examination. extracts of cultured cells caused acute death to mice when injected intraperitoneally after developing neurotoxic symptoms which resembled to those caused ...	1999	10414862
viability of dried vegetative trichomes, formation of akinetes and heterocysts and akinete germination in some blue-green algae under water stress.	almost all dried vegetative trichomes ofanabaena iyengarii, westiellopsis prolifica andnostochopsis lobatus died within 1 h, while those ofoscillatoria acuminata retained viability to some extent for 1 d under similar storage conditions. the viability of dried vegetative trichomes ofo. acuminata decreased about equally on storage at 20 degrees c in the light or in the dark, but dropped rapidly at 12 and 0 degrees c in the dark. vegetative trichomes ofa. iyengarii, n. lobatus andw. prolifica were ...	1999	18461490
a new model of phycobilisome in spirulina platensis.	phycobilisomes (pbs) were isolated from blue-green alga spirulina platensis. scanning tunneling microscope was used to investigate the three-dimensional structure of pbs deposited on freshly cleaved highly oriented pyrolytic graphite (hopg) in ambient condition at room temperature. the results showed that the rods of pbs radiated from the core to different directions in the space other than arrayed in one plane, which was different from the typical hemi-discoidal model structure. the diameter of ...	1999	18726501
anti-hiv activity of extracts and compounds from algae and cyanobacteria.	the human immunodeficiency virus (hiv) is the retrovirus that causes the acquired immune deficiency disease syndrome (aids). this review discusses the anti-hiv activity of extracts and compounds isolated from freshwater and marine algae, and cyanobacteria (formerly called "blue-green algae"). compounds and extracts with anti-hiv activity are also active against other retroviruses such as herpes simplex virus (hsv), but the amount of antiviral activity varies with the compound and the virus. most ...	2000	10702339
effects of organic and inorganic fertilisers on mosquito populations in rice fields of southern india.	the effects of nitrogenous (inorganic) fertilisers, organic manures and blue-green algae (bga) biofertiliser on mosquito populations (diptera: culicidae) were studied in rice fields of madurai, tamil nadu, south india, with particular attention to culex vishnui theobald, cx. pseudovishnui colless and cx. tritaeniorhynchus giles, the vectors of japanese encephalitis (je). the application of urea, a nitrogenous fertiliser, in rice fields significantly increased the grain yield and the population d ...	2000	11129699
amelioration of fly-ash by selected nitrogen fixing blue green algae.		2000	10656898
desert bighorn sheep mortality due to presumptive type c botulism in california.	during a routine telemetry flight of the mojave desert (california, usa) in august 1995, mortality signals were detected from two of 12 radio-collared female desert bighorn sheep (ovis canadensis) in the vicinity of old dad peak in san bernardino county (california). a series of field investigations determined that at least 45 bighorn sheep had died near two artificial water catchments (guzzlers), including 13 bighorn sheep which had presumably drowned in a guzzler tank. samples from water conta ...	2000	10682765
cyanobacterial toxins: removal during drinking water treatment, and human risk assessment.	cyanobacteria (blue-green algae) produce toxins that may present a hazard for drinking water safety. these toxins (microcystins, nodularins, saxitoxins, anatoxin-a, anatoxin-a(s), cylindrospermopsin) are structurally diverse and their effects range from liver damage, including liver cancer, to neurotoxicity. the occurrence of cyanobacteria and their toxins in water bodies used for the production of drinking water poses a technical challenge for water utility managers. with respect to their remov ...	2000	10698727
microcystin-lr toxicodynamics, induced pathology, and immunohistochemical localization in livers of blue-green algae exposed rainbow trout (oncorhynchus mykiss).	with this retrospective study, we investigated the temporal pattern of toxin exposure and pathology, as well as the topical relationship between hepatotoxic injury and localization of microcystin-lr, a potent hepatotoxin, tumor promoter, and inhibitor of protein phosphatases-1 and -2a (pp), in livers of mc-gavaged rainbow trout (oncorhynchus mykiss) yearlings, using an immunohistochemical detection method and mc-specific antibodies. h&e stains of liver sections were used to determine pathologica ...	2000	10774818
use of recombinant aequorin to study calcium homeostasis and monitor calcium transients in response to heat and cold shock in cyanobacteria.	we investigated the possibility of ca(2+) signaling in cyanobacteria (blue-green algae) by measuring intracellular free ca(2+) levels ([ca(2+)](i)) in a recombinant strain of the nitrogen fixing cyanobacterium anabaena strain sp. pcc7120, which constitutively expresses the ca(2+)-binding photoprotein apoaequorin. the homeostasis of intracellular ca(2+) in response to increasing external ca(2+) has been studied in this strain. the resting level of free ca(2+) in anabaena was found to be between 1 ...	2000	10806234
assessing potential health risks from microcystin toxins in blue-green algae dietary supplements.	the presence of blue-green algae (bga) toxins in surface waters used for drinking water sources and recreation is receiving increasing attention around the world as a public health concern. however, potential risks from exposure to these toxins in contaminated health food products that contain bga have been largely ignored. bga products are commonly consumed in the united states, canada, and europe for their putative beneficial effects, including increased energy and elevated mood. many of these ...	2000	10811570
[the postradiation use of vitamin-containing complexes and a phycocyanin extract in a radiation lesion in rats].	wistar rats have been exposed to x-rays with a dose of 5 gy. significant decrease in dehydrogenase activity, energy-rich phosphate level and efficiency of antioxidant defence and significant increase in pyruvate amount were observed within 4 weeks. it was also found that the feeding of exposed rats with phycocyanin extract from blue-green algae spirulina platensis lead to correcting effect. the same result was observed after injections of tocopherol or complex of six water-soluble vitamins. the ...	2000	10907410
vegetative survival, akinete formation and germination in three blue-green algae and one green alga in relation to light intensity, temperature, heat shock and uv exposure.	the mere vegetative survival was not sufficient but suitable growth conditions were required for akinete formation to occur in the blue-green algae anabaena iyengarii, westiellopsis prolifica, nostochopsis lobatus and in the green alga pithophora oedogonia. in all algae, akinetes were neither formed nor germinated in darkness, and while dim light of 300 lx was sufficient for most of akinetes to germinate and also to maintain vegetative survival, it was not adequate for optimum akinete formation. ...	2000	11347271
structural organization of microcystin biosynthesis in microcystis aeruginosa pcc7806: an integrated peptide-polyketide synthetase system.	blooms of toxic cyanobacteria (blue-green algae) have become increasingly common in the surface waters of the world. of the known toxins produced by cyanobacteria, the microcystins are the most significant threat to human and animal health. these cyclic peptides are potent inhibitors of eukaryotic protein phosphatases type 1 and 2a. synthesized nonribosomally, the microcystins contain a number of unusual amino acid residues including the beta-amino polyketide moiety adda (3-amino-9-methoxy-2,6, ...	2000	11033079
the use of bioluminescent biotests for study of natural and laboratory aquatic ecosystems.	a set of bioluminescent tests was developed to monitor water quality in natural and laboratory ecosystems. it consisted of four bioluminescent systems: luminous bacteria, coupled enzyme system nadh:fmn-oxidoreductase-luciferase and triplet enzyme systems with alcohol dehydrogenase and trypsin. the set of biotests was applied for a small forest pond (siberia, russia), laboratory microecosystems polluted with benzoquinone and a batch culture of blue-green algae. thereby effects of natural water co ...	2001	11272913
crystal structure of a light-harvesting protein c-phycocyanin from spirulina platensis.	the crystal structure of c-phycocyanin, a light-harvesting phycobiliprotein from cyanobacteria (blue-green algae) spirulina platensis has been solved by molecular replacement technique. the crystals belong to space group p2(1) with cell parameters a = 107.20, b = 115.40, c = 183.04 a; beta = 90.2 degrees. the structure has been refined to a crystallographic r factor of 19.2% (r(free) = 23.9%) using the x-ray diffraction data extending up to 2.2 a resolution. the asymmetric unit of the crystal ce ...	2001	11352634
identification of anatoxins in blue-green algae food supplements using liquid chromatography-tandem mass spectrometry.	blue-green algae (cyanobacteria) in tablets and capsules, which are marketed as health food supplements, were investigated for the presence of neurotoxins related to anatoxin-a. these neurotoxins, which are nicotinic agonists, were investigated using isocratic micro-liquid chromatograph-tandem mass spectrometry (micro-lc-ms-ms). the investigated compounds were anatoxin-a and homoanatoxin-a, together with their degradation products, dihydroanatoxin-a, epoxyanatoxin-a, dihydrohomoanatoxin-a and ep ...	2001	11407751
algal growth inhibition effects and inducement modes by plant-producing phenols.	evaluated here are the inhibitory effects on blue-green algae (microcystis aeruginosa) produced by nine plant-producing phenols (caffeic, p-coumaric, ferulic, protocatechuic, sinapic, syringic, and vanillic acids, catechol, and hydroquinone), two plant-produced acids (quinic and shikimic acid), phenol, resorcinol, hydroxy hydroquinone, and phloroglucinol. algal assays confirmed growth inhibition of m. aeruginosa by polyphenols, i.e., caffeic/protocatechuic acid, catechol, hydroquinone, hydroxy h ...	2001	11329689
production and specificity of mono and polyclonal antibodies against microcystins conjugated through n-methyldehydroalanine.	microcystins (mcs) are a group of closely related toxic cyclic heptapeptides produced by common cyanobacteria (blue-green algae). their toxicity is associated with specific inhibition of intracellular protein phosphatases type-1 and type-2a (pp1 and pp2a, respectively). we have developed a battery of antibodies to microcystins using chemical modification (aminoethylation) of one of its core amino acids, n-methyl-dehydroalanine. the developed antibodies displayed different reactivities to closely ...	2001	11024487
ozonation of nom and algal toxins in four treated waters.	the occurrence of cyanobacteria (blue-green algae) blooms and the possibility of production of cyanotoxins (algal toxins) have become major concerns for drinking water providers worldwide. ozone has been shown to be effective for the destruction of some classes of toxins under specific conditions, although most researchers agree that the dose and contact time required will depend on water quality. the clarification of the relative effects of water quality parameters such as dissolved organic car ...	2001	11257877
gelation of edible blue-green algae protein isolate (spirulina platensis strain pacifica): thermal transitions, rheological properties, and molecular forces involved.	proteins isolated from blue-green algae spirulina platensis strain pacifica were characterized by visible absorption, differential scanning calorimetry (dsc), viscometry, and dynamic oscillatory rheological measurements. unique thermal unfolding, denaturation, aggregation, and gelation of the algal protein isolate are presented. dsc analysis showed that thermal transitions occur at about 67 and 109 degrees c at neutral ph. calcium chloride stabilized the quaternary structure against denaturation ...	2001	11262046
antioxidant activity of different fractions of spirulina platensis protean extract.	spirulina platensis, planktonic blue-green algae, is gaining increasing attention because of its nutritional and medicinal properties. this microalgae contains phycobiliproteins (phycocyanin and allophycocyanin). previous reports from our laboratory have shown that a protean extract of s. platensis is a potent free-radical scavenger (hydroxyl and peroxyl radicals) and inhibits microsomal lipid peroxidation. the aim of this study was to purify and characterize phycocyanin of s. platensis. besides ...	2001	11482785
determination of microcystins in blue-green algae, fish and water using liquid chromatography with ultraviolet detection after sample clean-up employing immunoaffinity chromatography.	anti-microcystin lr immunnoaffinity cartridges were evaluated for their ability to selectively remove microcystins from extracts of blue-green algae, fish and water samples for subsequent analysis by liquid chromatography with uv absorbance detection at 238 nm. blue-green algae and fish samples were extracted with 75% methanol in water. a portion of the extract was diluted and passed through an immunoaffinity cartridge. water samples were applied directly to the cartridge. the cartridge was rins ...	2001	11486855
the toxins of cyanobacteria.	cyanobacteria, formerly called "blue-green algae", are simple, primitive photosynthetic microorganism wide occurrence in fresh, brackish and salt waters. forty different genera of cyanobacteria are known and many of them are producers of potent toxins responsible for a wide array of human illnesses, aquatic mammal and bird morbidity and mortality, and extensive fish kills. these cyanotoxins act as neurotoxins or hepatotoxins and are structurally and functionally diverse, and many are derived fro ...	2001	11488138
metal levels in feathers of cormorants, flamingos and gulls from the coast of namibia in southern africa.	arsenic, cadmium, chromium, lead, manganese, mercury, selemium, and tin concentrations were measured in the feathers of cape cormorant (phalacrocorax capensis), hartlaub's gull (larus hartlaubii), kelp gull (larus dominicanus), and lesser flamingo (phoeniconaias minor) from the coast of namibia in southern africa. metal concentrations in feathers represent the concentrations in the blood supply at the time of feather formation. cape cormorants are piscivores; kelp gulls are primarily piscivores; ...	2001	11465667
[effect of blue-green alga (cyanobacteria) and their exometabolites on formation of resting forms and variability of yersinia pseudotuberculosis].	research, carried out with the use of bacteriological methods and polymerase chain reaction, revealed that the transformation of y. pseudotuberculosis, associated with blue-green algae anabaena variabilis, into resting (noncultivable) forms took shorter time than in soil extract containing no algae. the exometabolites of "old" cultures of these algae sharply accelerated the formation of resting y. pseudotuberculosis forms. the influence of the algae and the products of their metabolism was manif ...	2001	11550552
analysis of cyanobacterial toxins by physicochemical and biochemical methods.	cyanobacteria (blue-green algae) produce a wide range of low molecular weight metabolites that include potent neurotoxins, hepatotoxins, and cytotoxins. the accumulation of such toxins in freshwaters, and in brackish and marine waters presents hazards to human and animal health by a range of exposure routes. a review is presented of developments in the detection and analysis of cyanobacterial toxins, other than bioassays, including application of physicochemical, immunoassays, and enzyme-based m ...	2001	11601485
development of a fluorescence based high throughput assay for antagonists of the human chorionic gonadotropin receptor extracellular domain: analysis of peptide inhibitors.	a simple method for prompt fluorescent detection of inhibitors of human chorionic gonadotropin (hcg) binding to the extracellular domain of the human luteinizing hormone/chorionic gonadotropin (hlh/cg) receptor was developed for high throughput screening (hts). construction and analysis of a recombinant phage that displays the extracellular binding domain of the hlh/cg receptor on its surface and specifically binds hcg was previously described. to facilitate the identification of molecules that ...	2001	11689111
water-quality control, monitoring and wastewater treatment in lithuania 1950 to 1999.	the lithuanian water-management system developed on the basis of soviet regulations in 1950-1990. surface-water quality monitoring started in the 1950s, and the system was improved in the 1960s. today, 48 rivers are being monitored using up to 70 parameters. statutory monitoring of discharges started in 1962, wastewater standards were issued in 1957 and 1966, and then revised in 1996. wastewater-treatment plants were built first in rural areas, in factories since the 1950s, and later in towns. s ...	2001	11697266
partitioning of monomethylmercury between freshwater algae and water.	phytoplankton-water monomethylmercury (mehg) partition constants (kpi) have been determined in the laboratory for two green algae selenastrum capricornutum and cosmarium botrytis, the blue-green algae schizothrix calcicola, and the diatom thallasiosira spp., algal species that are commonly found in natural surface waters. two methods were used to determine kpi, the freundlich isotherm method and the flow-through/dialysis bag method. both methods yielded kpi values of about 10(6.6) for s. caprico ...	2001	11718342
critical role of reactive oxygen species formation in microcystin-induced cytoskeleton disruption in primary cultured hepatocytes.	cyanobacteria (blue-green algae)-contaminated water is a worldwide public health problem. microcystins are a group of liver-specific toxins generated by cyanobacteria. it is generally believed that the protein phosphorylation that leads to the disruption of intermediate filaments plays an important role in microcystin-induced hepatotoxicity. however, the mechanisms that contribute to the microcystin-induced alterations of microtubules and microfilaments are not fully understood. in the present s ...	2001	11732701
ultrasonic irradiation for blue-green algae bloom control.	a novel application of ultrasonic irradiation for rapid control of blue-green algae (bga) bloom was investigated. potassium iodide (ki) experiments demonstrated that frequency and input power are the major factors that affect the ultrasonic irradiation intensity. short exposure (3 s) to ultrasonic irradiation (120 w input power, 28 khz) effectively settled naturally growing bga suspension. electron microscopy reconfirmed that sedimentation was caused by the disruption and collapse of gas vacuole ...	2001	11329801
comparison of liquid chromatography/mass spectrometry, elisa, and phosphatase assay for the determination of microcystins in blue-green algae products.	more than 100 samples of blue-green algae products (consisting of aphanizomenon, spirulina, and unidentified blue-green algae) in the form of pills, capsules, and powders were collected from retail outlets from across canada. the samples were extracted with 75% methanol in water and centrifuged to remove solids. aliquots of the extracts along with spiked blank sample extracts were sent to each participating laboratory and independently analyzed for microcystins by enzyme-linked immunosorbent ass ...	2001	11501902
complex dynamics of adaptation in a nonaxenic microcystis culture. 2. computer simulation of dinotrophenol effects.	a hypothesis was modeled to account for complex 20-day dynamics in a culture of blue-green algae microcystis and heterotrophic bacteria exposed to 2,4-dinitrophenol (dnp). in trials with little or no added dnp, a limiting factor (light or co(2)) may cause algal density to fluctuate after 14 days of increase. such factors may be unimportant at levels of dnp that restrict photosynthesis. bacterial growth may be limited by organic substrate, and bacteria may be more resistant to dnp than blue-green ...	2001	11222033
the application of powdered activated carbon for mib and geosmin removal: predicting pac doses in four raw waters.	blooms of blue-green algae in reservoirs often produce the musty-earthy taste and odour algal metabolites 2-methylisoborneol (mib) and geosmin. mib and geosmin are not removed by conventional water treatment and their presence in the distribution system, even at low ng l-1 levels, can result in consumer complaints. powdered activated carbon (pac) can effectively remove mib and geosmin when the correct dose is applied. the homogeneous surface diffusion model (hsdm) was used to predict pac doses r ...	2001	11268853
congener-independent immunoassay for microcystins and nodularins.	cyanobacteria (blue-green algae) (e.g., microcystis and nodularia spp.) capable of producing toxic peptides are found in fresh and brackish water worldwide. these toxins include the microcystin (mc) heptapeptides (>60 congeners) and the nodularin pentapeptides (ca. 5 congeners). cyanobacterial cyclic peptide toxins are harmful to man, other mammals, birds, and fish. acute exposure to high concentrations of these toxins causes liver damage, while subchronic or chronic exposure may promote liver t ...	2001	11775161
effect of various foods on biomphalaria alexandrina and bulinus truncatus and their susceptibility to schistosome miracidia.	the tested foods are tropical fish food (tetramine), rat food, blue green algae, dried lettuce leaves and a mixture of all these foods. the results indicated that feeding of b. alexandrina on a mixture of foods increased their growth and survival rates and their susceptibility to s. mansoni. tetramine elevated the egg-laying capacity of snails compared to other tested foods. the hatchability of eggs of b. alexandrina fed on algae for a period of 16 weeks showed the highest rate followed by snail ...	2001	11775118
sources of the eutrophication problems associated with toxic algae: an overview.	blooms of cyanobacteria (toxic blue-green algae) can produce health and environmental hazards in water, including water used for drinking or recreational purposes. how, why, and when these blooms are produced, as well as how to deal with them, are questions whose answers are vital to the safeguarding of public health in regions where the algae occur. the blooms are linked to eutrophication of water, and this paper discusses the eutrophication problems, their nature, and their relevance to the pr ...	2001	11764678
spatial impact of the oder river plume on water quality along the south-western baltic coast.	the oder (odra) river is the most important nutrient source and pollutant for the south-western baltic sea. adjacent german-polish coastal waters, the oder (szczecin) lagoon and the oder (pomeranian) bight therefore suffer from severe eutrophication and water quality problems. at the same time, summer (bathing) tourism is the most important economical factor in this coastal zone, especially on the islands of usedom and wolin. on the basis of model simulations and remote sensing data we analysed ...	2001	11759158
harmful freshwater algal blooms, with an emphasis on cyanobacteria.	suspended algae, or phytoplankton, are the prime source of organic matter supporting food webs in freshwater ecosystems. phytoplankton productivity is reliant on adequate nutrient supplies; however, increasing rates of nutrient supply, much of it manmade, fuels accelerating primary production or eutrophication. an obvious and problematic symptom of eutrophication is rapid growth and accumulations of phytoplankton, leading to discoloration of affected waters. these events are termed blooms. bloom ...	2001	12805693
trophic relations in two lakes from the bulgarian black sea coast and possibilities for their restoration.	based on quantitative data on nutrients, light penetration, phytoplankton, zooplankton and zoobenthos obtained in the period 1992-1994 the relations between trophic levels were studied by means of statistical analysis. the two lakes are distinguished by relatively high transfer efficiency between phytoplankton and zooplankton, which depends on the size distribution among zooplankton and percentage of blue-green algae. the bottom up influence seems to prevail over the top-down influence, water su ...	2002	12420960
cyanopeptide analogues: new lead structures for the design and synthesis of new thrombin inhibitors.	this contribution deals with the structure-based design and syntheses of the new serine protease inhibitors ra-1001 and ra-1002, which are analogues of the blue-green algae derived cyanopeptide aeruginosin 98-b. both compounds inhibit thrombin with ki values of 5.6 microm and 8.7 microm, respectively.	2002	12611274
on the natural diet of daphnia laevis in the eutrophic pampulha reservoir (belo horizonte, minas gerais).	the aim of this study was to assess the major food items ingested by adult specimens of daphnia laevis within the eutrophic pampulha reservoir in belo horizonte, minas gerais, brazil. the gut content was analyzed after addition of sodium hypochlorite and also through the examination of dissected guts under scanning electron microscopy. the results showed that chlorophyceae was the main food item ingested, representing c. 80.5% of the total ingested food. moreover, eutetramorus fottii, coelastrum ...	2002	12530180