Studies on the hormonal relationships of algae in pure culture

Summary The effect of potential precursors of Indole-3-acetic acid (IAA) on the growth (increase in dry weight) of Anacystis nidulans, Chlorogloea fritschii, Phormidium foveolarum, Nostoc muscorum and Tolypothrix tenuis have been investigated under as sterile conditions as possible.Tryptamine showed a marked stimulation of growth indicating its possible conversion to IAA. Tryptophan at a hormonal concentration promoted growth in only 1 species, Chlorogloea fritschii. Indole stimulated the growth of Chlorogloea fritschii, Nostoc muscorum and Tolypothrix tenuis. Anthranilic acid promoted the growth of Nostoc muscorum, it failed to stimulate the growth of Chlorogloea fritschii. Anthranilonitrile promoted the growth of Nostoc muscorum and Chlorogloea fritschii. -Alanine promoted the growth of Nostoc muscorum, Tolypothrix tenuis and Chlorogloea fritschii at hormonal concentrations.     

Studies on the hormonal relationships of algae in pure culture

Summary Indole-3-acetic acid (IAA) stimulated the growth (increase in dry weight) of the blue-green algae Anacystis nidulans, Chlorogloea fritschii, Phormidium foveolarum, Nostoc muscorum, Anabaena cylindrica, and Tolypothrix tenuis and the green algae Chlorella pyrenoidosa, Ankistrodesmus falcatus and Scenedesmus obliquus growing under as sterile conditions as possible. The optimum concentration varied from species to species; in the blue-green algae it ranged from 10^-5 to 10^-9 M and in the green algae it was 10^-3 M. These results are discussed in the light of present studies in this field.     

Photochromic Pigments from Blue-Green Algae: Phycochromes a, b, and c

Aqueous extracts of blue-green algae were fractionated by electrofocusing. In all algae investigated, fractions with iso-electric points at or near 4.6 showed photochromic behaviour analogous to that of phytochrome, although they were sensitive to light of shorter wavelength. Three main types of photochromic pigments were found: Phycochrome a (in Tolypothrix distorta, Phormidium luridum, Nostoc muscorum 1453/12, and Anacystis nidulans) has one form absorbing maximally at about 590 nm (formed under red light) and one absorbing maximally at about 630 nm (formed under green light). Phycochrome b (in Tolypothrix distorta) has one form absorbing maximally near 510 nm and one form absorbing maximally at 570 nm (formed in yellow-green and blue-green light, respectively). Phycochrome c (in Nostoc muscorum A and probably in Tolypothrix tenuis) has one form absorbing maximally at 650 nm (formed under green light) and one absorbing very weakly in the green region (formed under red light). The conversion of Phormidium phycochrome a from its red-absorbing form to its green-absorbing form causes the same spectral change as if an f-chromophore of phycocyanin were transformed into an s-chromophore. The quantum yield for this conversion is estimated to be 0.1, while the quantum yield for the reversion is estimated to be 0.4 on the assumption that the absorption coefficients are those of f- and s-chromophores. Phycochrome c is less light-sensitive than phycochromes a and b.     

A retained viability index (RVI10) for evaluation of a cyanobacterial powder fertilizer

The preparation of a dry and powder fertilizer based on five nitrogen-fixing cyanobacterial strains is described. Tolypothrix tenuis and Nostoc muscorum resisted the drying and milling processes and showed a suitable recovering capacity in liquid media of different pH and salinity. Although a decrease in the cellular viability was observed with the storage time, the biomass of Nostoc muscorum retained viability for 16 months. The results were evaluated in terms of the retained viability index (RVI₁₀) specifically designed for the fertilizer material.     

Photoproduction of H2 and NADPH2 by polyurethane-immobilized cyanobacteria

Summary Cyanobacterial cells were grown in polyurethane foams (polyester or polyvinyl types). Chlorogloea fritschii, Nostoc muscorum and Mastigocladus laminosus remained immobilized in the foams and were used for continuous photoproduction of H₂ from ascorbate with methyl viologen (MV) and hydrogenase or Pt catalysts, for periods in excess of 9 days. Foam-immobilized N. muscorum continuously photoreduced exogenous NADP for at least 24 h in the presence of Fd-NADP reductase with ascorbate as electron donor.     

Glycollate oxidation by thylakoids of the cyanobacteria Anabaena cylindrica,Nostoc muscorum and Chlorogloea fritschii

The intracellular distribution of glycollate dehydrogenase EC 1.2.1.17 has been investigated in extracts of the cyanobacteria (blue-green algae) Anabaena cylindrica, Nostoc muscorum and Chlorogloea fritschii. Most of the enzyme activity was associated with a chlorophyll-containing cell-free pellet, which also exhibited Photosystem I and II activities. Sucrose density gradient centrifugation of this washed pellet resulted in the formation of a green band within which maximal chlorophyll concentration and enzymic glycollate oxidation coincided. Antiserum raised to this fraction obtained from A. cylindrica inhibited glycollate dehydrogenase and Photosystem II activity. The data indicate that most of the cyanobacterial glycollate dehydrogenase is associated with the thylakoids and thus provide evidence for the dual role of these membranes in photosynthetic and respiratory processes.Abbreviations DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea - DCPIP 2,6-dichlorophenolindophenol - DPC diphenylcarbazide     

Role of algalization in rice growth,yield and incidence of infestation with the stem borerChilo agamemnon Bles. and the leaf minerHydrellia prosternalis Deeming in the Nile Delta

Blue-green algae as a soil-based inoculum was applied to short-duration Indica rice in combination with 72 kg N/ha and compared with just N fertilization applied as 144 kg N/ha. Fertilizer N was applied in two equal doses 25 days after transplanting and at mid-tillering stage. The algal inoculum, which containedAnabaena cylindrica, Anabaena oryzae, Nostoc muscorum andTolypothrix tenuis, was applied at 100 kg/ha fresh material (90% moisture) 5 days after transplanting. Five different combinations of microelements were sprayed as a foliar application simultaneously with fertilizer N. Plant performance was enhanced by inoculation with algae and microelements compared with complete N fertilization only. Natural infestation with the stem borer,Chilo agamemnon, and leaf miner,Hydrellia prosternalis, decreased significantly during growth and up to harvesting with application of algae, Endosulfan, and increased with application of microelements.     

Rice performance and natural infection with blast (Pyricularia oryzae Cav.) under different algalization techniques and rates of fertilizer nitrogen

Japonica rice, Giza 171, was inoculated with either a dry or fresh soil-based inoculum of cyanobacteria containingAnabaena cylindrica, Anabaena oryzae, Nostoc muscorum andTolypothrix tenuis together with fertilization with urea at 0, 36, 72, or 108 kg N/ha. Fresh inoculum enhanced plant growth, yield and N content in comparison with the dry one. The efficiency of nitrogen utilization from the urea at all N concentrations was improved by using the fresh inoculum. Natural infection with leaf and neck blast caused byPyricularia oryzae Cav. increased with increasing N fertilization. Algalization with the fresh inoculum decreased leaf blast while neck blast was slightly higher in the algalized sub-plots but without considerable yield damage.     

Effects of Radiations on Blue-green Algae: II. Effects in Growth

The unicellular blue-green alga Anacystis nidulans was repeatedlytreated with X-rays and radiophosphate (32P) during successivesubcultures. The strains so obtained were characterized by comparisonwith the untreated control strain, with respect to their resistanceto ultraviolet light, X-rays, streptomycin, and isoniazid. The³²P-treated strain was found to be relatively more resistantto streptomycin than the untreated strain and the X-rayed strainwas found to be relatively rnore sensitive to isoniazid thanthe control. In old cultures, cells of the X-rayed strain weresignificantly smaller than those of the untreated strain. The effects of X-rays on cell- and heterocyst dimensions ofthe nitrogen-fixing alga Chlorogloea fritschii Mitra were studied.In the irradiated material the cell diameter and heterocystbreadth were greater, rather than smaller, than in unirradiatedmaterial.     

Contributions of algalization to rice growth,yield, N attributes and incidence of infestation with the blast fungusPyricularia oryzae under different fungicidal treatments

Inoculation of the Japonica rice, Giza 171, with blue-green algae along with 36 kg N/ha or complete N fertilization by 108 kg N/ha were tested along with blast-controlling fungicides: Kitazin-17, Fuji-one and Beam. The algal inoculum, which containedAnabaena cylindrica, Anabaena oryzae, Nostoc muscorum and Tolypothrix tenuis, was applled as 100 kg soil-based inoculum (90% moisture)/ha 5 days after transplanting. Plant growth, yield, N content and fertilizer-N-use efficiency were increased and the incidence and severity of leaf and neck intection withPyricularia oryzae were decreased by treatment with the fungicides applied with the algae along with 36 kg N/ha inslead of 108 kg N/ha without algae.

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Résumé On a testé l'inoculation du riz Japonica, Giza 171 avec l'algue bleu-verte, simultanément avec la fertillisation azotée soit à 36 kg N/ha solt complète à 108 kg N/ha et simultanément avec les fongicides Kitazin-17, Fuji-1 et Beam. L'inoculum d'algues, qui contenaltAnabaena cylindrica, Anabaena oryzae, Nostoc muscorum etTolypothrix tenuis, étalt appliqué à raison de 100 kg humides à 90% d'inoculum à base de sol par ha, 5 jours aprés la transplantation. La croissance des plantes, leur rendement, leur contenu azoté ainsi que l'efficience de la fertillisation azotée ont augmenté tandis que l'incidence et la sévérité de l'infection des feullies et du col parPyricularia oryzae ont décru par le traitement aux fongicides appliqué simultanément avec les algues et 36 kg N/ha par rapport au traitement à 108 kg N/ha sans algues.

     

Effects of some inorganic elements on nitrogen-fixation in blue-green algae and some ecological aspects of pollution.

Nitrogen-fixation by two species of Nostoc, one of them a lichen phycobiont, was generally stimulated by low concentrations of arsenic, cadmium, nickel, lead, palladium, and zinc. Higher concentrations (0.025 to 0.125 ppm) of arsenic, nickel, and palladium were also stimulatory; however, higher concentrations of cadmium, lead, and zinc tended to inhibit fixation. With the exception of palladium and zinc at low concentrations these six tested elements tended to inhibit nitrogen-fixation in Chlorogloea fritschii and Westiellopsis sp.     

The Accumulation and Degradation Dynamics of Cyanophycin in Cyanobacterial Cells Grown in Symbiotic Associations with Plant Tissues and Cells

Five different artificial associations of cyanobacterial cells with the cells or tissues of nightshade and rauwolfia were studied. The associations grown on nitrogen-containing media produced heterocysts. Cyanobacterial cells in the associations retained their ability to take up combined nitrogen from the medium, to store it in the form of cyanophycin granules, and to use them in the process of symbiotic growth. The synthesis and degradation of cyanophycin granules in cyanobacterial cells were more active in the associations than in monocultures. In the symbiotic associations of Chlorogloeopsis fritschii ATCC 27193 with Solanum laciniatum cells and of Nostoc muscorum CALU 304 with the Rauwolfia serpentina callus, heterocysts were produced with a 3- to 30-fold higher cyanophycin content than in pure cyanobacterial cultures. In contrast, in the association of N. muscorum CALU 304 with the Solanum dulcamara callus, heterocysts were produced with a lower cyanophycin content than in the N. muscorum CALU 304 pure culture. The degradation of cyanophycin granules in N. muscorum CALU 304 cells grown in associations with plant tissues or cells was subjected to mathematical analysis. The activation of cyanophycin degradation and heterocyst differentiation in the associations N. muscorum CALU 304–R. serpentinaand C.fritschii–S. laciniatum was accompanied by an enhanced synthesis of the nitrogen-containing alkaloids in plant cells. The data obtained suggest that an integrated system of nitrogen homeostasis can be formed in symbiotic associations. Depending on the growth stage of an association, its plant member can either stimulate the accumulation of combined nitrogen in vegetative cyanobacterial cells in the form of cyanophycin granules, activate their degradation, or initiate the formation of heterocysts independently of the cyanobacterial combined nitrogen deprivation sensing-signaling pathway.     

Bioactivity of intra and extracellular substances from cyanobacteria and lactic acid bacteria on “wood blue stain” fungi

Cyanobacteria (photoautotrophic prokariota) have potential for the control of pathogenic bacteria and fungi. The effect of intra and extracellular products from cyanobacterial strains on the growth of fungi isolated from “wood blue stain,” was tested. Extracellular products were obtained by concentration and sterilization of the culture medium where cyanobacteria were grown. Cyanobacterial substances promoted or inhibited fungal growth according to the fungal and cyanobacterial strains tested. Extracellular products from Nostoc muscorum 79a and the methanolic extract from Microchaete tenera 84b biomass inhibited growth of Sphaeropsis sapinea 2157 (64.7 and 775.6%, respectively). Extracellular products of Nostoc piscinale 59 and biomass methanolic extract from N. muscorum 79a produced the highest growth promotion of Trichoderma boningii 452 (105.0%) and T. viride 993 (136.7%). Extracellular products of the heterotrophic lactic acid bacterium Streptococcus termophilus were also tested and strongly inhibited (64–92%) all the fungal strains. The tested fungi have different sensitivity to the bioactive substances present in the biomass and/or the culture medium of the studied cyanobacteria and lactic acid bacterium. N. muscorum 79a, M. tenera 84b, and S. termophilus have potential to control the wood blue stain fungi by a friendly environmental alternative.     

Studies on the hormonal relationships of algae in pure culture

Summary The metabolism of L-tryptophan (methylene-C¹⁴) by Chlorogloea fritschii has been studied in sterile conditions. This organism can produce Indole-3-Acetic acid (IAA) from tryptophan. Tryptamine has been shown to be one of the intermediate compound in the conversion of tryptophan to IAA. The formation of Indole-3-pyruvic acid could not be demonstrated.     

Untersuchungen zum chemischen Aufbau der Zellwände von Anacystis nidulans und Chlorogloea fritschii

Zusammenfassung Die Zellwände der einzelligen Cyanophyceen Anacystis nidulans und Chlorogloea fritschii wurden nach Homogenisation durch fraktionierte Zentrifugation isoliert und ihre Reinheit elektronenmikroskopisch kontrolliert.Durch chemische Untersuchung der isolierten Wände konnte eine Beteiligung von Cellulose und Pectin ausgeschlossen werden.Dagegen enthalten die Zellwände die Mucopolymerbausteine N-Acetylglucosamin, N-Acetylmuraminsäure, Glutaminsäure, Diaminopimelinsäure und Alanin, bei Anacystis in den Molverhältnissen 1,34:1,07:1,52:1,0:2,4.Dieser Befund und die Tatsache, daß die isolierten Zellwände von Anacystis durch Lysozym aufgelöst werden können, spricht für das Vorhandensein einer Stützschicht in der Zellwand, die die gleiche Zusammensetzung hat wie bei gramnegativen Bakterien. Außerdem wurde Galaktosamin nachgewiesen, das bei Anacystis etwa in gleicher molarer Konzentration vorkommt wie N-Acetylglucosamin. Der Nachweis von zehn Aminosäuren läßt vermuten, daß Proteine in die Zellwand eingebaut sind. Die Lipidsubstanzen der Zellwand wurden durch Extraktion und Chromatographie nachgewiesen aber nicht näher analysiert.

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Summary Cell walls of the blue green algae Anacystis nidulans and Chlorogloea fritschii have been isolated by fractionated centrifugation after homogenization in a Mickel-disintegrator by shaking with glass beads. The purity of cell walls was controlled in the electron microscope.The freeze-dried cell wall-material was hydrolyzed 14 h in 4 n HCl for chromatography of amino acids and amino sugars, or 3 h in n/1 HCl for sugar-chromatography. Neutral sugars and uronic acids are not detected. But the mucopolymer components N-acetylglucosamine, N-acetylmuramic acid, glutamic acid, diaminopimelic acid, and alanine in a molar ratio of 1.34:1.47:1.52:1.0:2.4, and eight unspecific amino acids in molar ratios from 0.1–0.4, and further galactosamine (molar ratio 1.2) are present. Isolated cell walls are lysed by lysozyme. But whole cells are transformed in spheroplasts only by completing the lysozyme-medium with ethylene diamine tetra-acetic acid. These facts suggest that walls of Chlorogloea and Anacystis are equipped with a rigid layer of mucopolymer like bacteria. The mucopolymer is responsible for rigidity and shape of cell walls. Besides mucopolymer proteins, lipids, and other unidentified substances compose the cell wall of these species of cyanophyta.

     

Glutathione reductase activity in heterocysts and vegetative cells of the cyanobacterium Nostoc muscorum

Glutathione reductase activity was detected and characterized in heterocysts and vegetative cells of the cyanobacterium Nostoc muscorum. The activity of the enzyme varied between 50 and 150 nmol reduced glutathione· min^-1·mg protein^-1, and the apparent K_m for NADPH was 0.125 and 0.200 mM for heterocysts and vegetative cells, respectively. The enzyme was found to be sensitive to Zn⁺² ions, however, preincubation with oxidized glutathione rendered its resistance to Zn⁺² inhibition. Nostoc muscorum filaments were found to contain 0.6–0.7mM glutathione, and it is suggested that glutathione reductase can regenerate reduced glutathione in both cell types. The combined activity of glutathione reductase and isocitrate dehydrogenase in heterocysts was as high as 18 nmol reduced glutathione·min^-1·mg protein^-1. A relatively high superoxide dismutase activity was found in the two cell types; 34.2 and 64.3 enzyme units·min^-1·mg protein^-1 in heterocysts and vegetative cells, respectively.We suggest that glutathione reductase plays a role in the protection mechanism which removes oxygen radicals in the N₂-fixing cyanobacterium Nostoc muscorum.Abbreviations DTNB 5-5-dithiobis-(2-nitrobenzoic acid) - EDTA ethylenediaminetetra-acetic acid - GR glutathione reductase (EC1.6.4.2) - GSH reduced glutathione - GSSG oxidized glutathione - OPT O-phtaldialdehyde - SOD superoxide dismutase (EC 1.15.1.1)     

Structural aspects of the adaptation of Nostoc muscorum to salt

The physiological and biochemical changes during the adaptation of Nostoc muscorum to salt are accompanied by specific structural changes. Cells of Nostoc muscorum exposed to saline medium vary in size and envelope organization. There are also drastic changes in the intracellular organization of the thylakoidal assembly. The heterocysts exhibit a preferential tolerance to NaCl rather than mannitol. These findings suggest that Nostoc muscorum is equipped with a specific physiological capacity for NaCl tolerance.     

Effect of sewage wastewater treated byNostoc muscorum andAnabaena subcylindrica on the growth ofZea mays andPhaseolus vulgaris

Zea mays (Sakha 321 ) andPhaseolus vulagris (Giza 6) were irrigated with sewage wastewater treated withNostoc muscorum andAnabaena subcylindrica. The results showed that irrigation of plants by untreated or treated wastewater caused stimulation in the measured growth parameters of both plants. In addition pigmentation as well as protein and carbohydrate contents were stimulated. This stimulation was attributed to the presence of high levels of essential nutrients such as nitrogen, phosphorus, and organic matters in wastewater. On the other side, there was a slight inhibitory effect of wastewater on some measured growth parameters of the plants. This effect may be due to the presence of some heavy metals in wastewater.     

EFFECT OF LYSOZYME (MURAMIDASE) ON MARINE AND FRESHWATER BLUE-GREEN ALGAE1

Marine blue-green algae, Lyngbya Lagerheimii, Microcoleus chthonoplastes, Plectonema terebrans, Agmenellum quadruplicatum, and freshwater blue-green algae, Anacystis nidulans, Anabaena variabilis, Nostoc muscorura, and Oscillatoria sp. treated with lysozyme (muramidase) formed spheroplasts but not protoplasts. The time needed for spheroplast induction varied with the species. Approximate internal osmotic pressures of the blue-green algae were determined. Marine algae generally had a higher osmotic pressure than freshwater algae.