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Sample records for alga cryptomonas paramecium

  1. Paramecium

    Energy Technology Data Exchange (ETDEWEB)

    Gortz, H.D.

    1988-01-01

    This book presents a survey of the current knowledge and research on Paramecium. Scientists find Paramecium a most useful object for the study of basic biological enigmas. To cover all aspects on the cell biology, cell physiology, genetics, developmental biology, ecology, endocytobiology, and molecular biology of Paramecium, specialists were asked to review their own fields. They have also included quite recent studies on the cytoskeleton, endo- and exocytosis, aging, sensory and membrane physiology, electrophysiology and motility.

  2. Characteristics of the digestive vacuole membrane of the alga-bearing ciliate Paramecium bursaria.

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    Kodama, Yuuki; Fujishima, Masahiro

    2012-07-01

    Cells of the ciliate Paramecium bursaria harbor symbiotic Chlorella spp. in their cytoplasm. To establish endosymbiosis with alga-free P. bursaria, symbiotic algae must leave the digestive vacuole (DV) to appear in the cytoplasm by budding of the DV membrane. This budding was induced not only by intact algae but also by boiled or fixed algae. However, this budding was not induced when food bacteria or India ink were ingested into the DVs. These results raise the possibility that P. bursaria can recognize sizes of the contents in the DVs. To elucidate this possibility, microbeads with various diameters were mixed with alga-free P. bursaria and traced their fate. Microbeads with 0.20μm diameter did not induce budding of the DVs. Microbeads with 0.80μm diameter produced DVs of 5-10μm diameter at 3min after mixing; then the DVs fragmented and became vacuoles of 2-5μm diameter until 3h after mixing. Each microbead with a diameter larger than 3.00μm induced budding similarly to symbiotic Chlorella. These observations reveal that induction of DV budding depends on the size of the contents in the DVs. Dynasore, a dynamin inhibitor, greatly inhibited DV budding, suggesting that dynamin might be involved in DV budding. Copyright © 2011 Elsevier GmbH. All rights reserved.

  3. Three Group-I introns in 18S rDNA of Endosymbiotic Algae of Paramecium bursaria from Japan

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    Hoshina, Ryo; Kamako, Shin-ichiro; Imamura, Nobutaka

    2004-08-01

    In the nuclear encoded small subunit ribosomal DNA (18S rDNA) of symbiotic alga of Paramecium bursaria (F36 collected in Japan) possesses three intron-like insertions (Hoshina et al., unpubl. data, 2003). The present study confirmed these exact lengths and insertion sites by reverse transcription-PCR. Two of them were inserted at Escherichia coli 16S rRNA genic position 943 and 1512 that are frequent intron insertion positions, but another insertion position (nearly 1370) was the first finding. Their secondary structures suggested they belong to Group-I intron; one belongs to subgroup IE, others belong to subgroup IC1. Similarity search indicated these introns are ancestral ones.

  4. The Evolutionary Relationships between Endosymbiotic Green Algae of Paramecium bursaria Syngens Originating from Different Geographical Locations.

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    Zagata, Patrycja; Greczek-Stachura, Magdalena; Tarcz, Sebastian; Rautian, Maria

    2016-01-01

    Paramecium bursaria (Ehrenberg 1831), a freshwater ciliate, typically harbors hundreds of green algal symbionts inside the cell. The aim of present study was the molecular identification of newly analyzed P. bursaria symbionts. The second aspect of the present survey was testing a hypothesis whether endosymbionts prefer the specified syngen of the host, and the specified geographical distribution. Ten strains of endosymbionts isolated from strains of P. bursaria originating from different geographical locations were studied. We analyzed for the first time, both the fragment of plastid genome containing 3'rpl36-5' infA genes and a fragment of a nuclear gene encoding large subunit ribosomal RNA (LSU rDNA). The analysis of the LSU rDNA sequences showed the existence of 3 haplotypes and the haplotype diversity of 0.733, and 8 haplotypes for the 3'rpl36-5' infA gene fragment and haplotype diversity of 0.956. The endosymbionts isolated from P. bursaria strains were identified as Chlorella vulgaris, Ch. variabilis and Micractinium conductrix. There was no correlation between the syngen of P. bursaria and the species of endosymbiont.

  5. Isolation and characterization of a virus (CvV-BW1 that infects symbiotic algae of Paramecium bursaria in Lake Biwa, Japan

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    Kasahara Masahiro

    2010-09-01

    Full Text Available Abstract Background We performed an environmental study of viruses infecting the symbiotic single-celled algae of Paramecium bursaria (Paramecium bursaria Chlorella virus, PBCV in Lake Biwa, the largest lake in Japan. The viruses detected were all Chlorella variabilis virus (CvV = NC64A virus. One of them, designated CvV-BW1, was subjected to further characterization. Results CvV-BW1 formed small plaques and had a linear DNA genome of 370 kb, as judged by pulsed-field gel electrophoresis. Restriction analysis indicated that CvV-BW1 DNA belongs to group H, one of the most resistant groups among CvV DNAs. Based on a phylogenetic tree constructed using the dnapol gene, CvV was classified into two clades, A and B. CvV-BW1 belonged to clade B, in contrast to all previously identified virus strains of group H that belonged to clade A. Conclusions We conclude that CvV-BW1 composes a distinct species within C. variabilis virus.

  6. Endosymbionts in paramecium.

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    Fujishima, Masahiro; Kodama, Yuuki

    2012-05-01

    Paramecium species are extremely valuable organisms to enable experiments for the reestablishment of endosymbiosis. This is investigated in two different systems, the first with Paramecium caudatum and the endonuclear symbiotic bacterium Holospora species. Although most endosymbiotic bacteria cannot grow outside the host cell as a result of their reduced genome size, Holospora species can maintain their infectivity for a limited time. We found that an 89-kDa periplasmic protein has an important function for Holospora's invasion into the target nucleus, and that Holospora alters the host gene expression; the host thereby acquires resistance against various stresses. The second system is the symbiosis between P. bursaria and symbiotic Chlorella. Alga-free P. bursaria and the algae retain the ability to grow without a partner. Consequently, endosymbiosis between the aposymbiotic host cells and the symbiotic algae can be reestablished easily by mixing them. We now found four checkpoints for the reestablishment of the endosymbiosis between P. bursaria and the algae. The findings in the two systems provide excellent opportunities for us to elucidate not only infection processes but also to assess the associations leading to eukaryotic cell evolution. This paper summarizes recent progresses on reestablishment of the primary and the secondary endosymbiosis in Paramecium. Copyright © 2011 Elsevier GmbH. All rights reserved.

  7. Strict stoichiometric homeostasis of Cryptomonas pyrenoidifera (Cryptophyceae in relation to N:P supply ratios

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    Eloísa Ramos Rodríguez

    2016-11-01

    Full Text Available A common freshwater cryptophyte, Cryptomonas pyrenoidifera, was cultivated in batch-cultures to analyze intraspecific variation in elemental stoichiometry along a broad gradient of pulsed phosphorus (P enrichment during the early acclimation period and to determine the immediate homeostatic capacity of the nitrogen-to-phosphorus (N:P ratio of this alga when nutrients are at saturating levels. Experimental results revealed that nitrogen (N and P cell quotas significantly increased with increasing P concentration. However, despite the wide range of N:P ratios in the medium, Cryptomonas N:P ratios were highly stable at higher P-level treatments, indicating a highly conservative behavior and suggesting strict elemental homeostasis when nutrients are at saturating levels. The strictly homeostatic N:P ratio appears to be attributable to their high potential for a fast luxury consumption of both N and P after a brief and intense episode of increased resource availability and to physiological limits on their nutrient storage capacity. Most importantly, the N:P biomass ratio at nutrient saturating levels converged around 11:1, which was the observed ratio of maximum internal cell quotas for N and P (i.e. Qmax,N:Qmax,P under the prevailing experimental conditions. This value is particularly informative for C. pyrenoidifera because it represents cell storage quotients and may be a taxon-specific evolutionary optimum, providing a reference point to infer the grade of nutrient-limitation. The experimental data give ranges of variation in C. pyrenoidifera elemental composition permitting, among others, proper parameterization of cryptophyte stoichiometry models.

  8. Algae

    Czech Academy of Sciences Publication Activity Database

    Raven, John A.; Giordano, Mario

    2014-01-01

    Roč. 24, č. 13 (2014), s. 590-595 ISSN 0960-9822 Institutional support: RVO:61388971 Keywords : algae * life cycle * evolution Subject RIV: EE - Microbiology, Virology Impact factor: 9.571, year: 2014

  9. Association of Paramecium bursaria Chlorella viruses with Paramecium bursaria cells: ultrastructural studies.

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    Yashchenko, Varvara V; Gavrilova, Olga V; Rautian, Maria S; Jakobsen, Kjetill S

    2012-05-01

    Paramecium bursaria Chlorella viruses were observed by applying transmission electron microscopy in the native symbiotic system Paramecium bursaria (Ciliophora, Oligohymenophorea) and the green algae Chlorella (Chlorellaceae, Trebouxiophyceae). Virus particles were abundant and localized in the ciliary pits of the cortex and in the buccal cavity of P. bursaria. This was shown for two types of the symbiotic systems associated with two types of Chlorella viruses - Pbi or NC64A. A novel quantitative stereological approach was applied to test whether virus particles were distributed randomly on the Paramecium surface or preferentially occupied certain zones. The ability of the virus to form an association with the ciliate was investigated experimentally; virus particles were mixed with P. bursaria or with symbiont-free species P. caudatum. Our results confirmed that in the freshwater ecosystems two types of P. bursaria -Chlorella symbiotic systems exist, those without Chlorella viruses and those associated with a large amount of the viruses. The fate of Chlorella virus particles at the Paramecium surface was determined based on obtained statistical data and taking into account ciliate feeding currents and cortical reorganization during cell division. A life cycle of the viruses in the complete symbiotic system is proposed. Copyright © 2011 Elsevier GmbH. All rights reserved.

  10. Morphological and Molecular Characterization of Paramecium (Viridoparamecium nov. subgen.) chlorelligerum Kahl, 1935 (Ciliophora)

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    KREUTZ, MARTIN; STOECK, THORSTEN; FOISSNER, WILHELM

    2013-01-01

    We redescribe Paramecium chlorelligerum, a forgotten species, which Kahl (1935) briefly but precisely described in the addendum to his ciliate monographs as a Paramecium with symbiotic green algae. The redescription is based on classical morphological methods and the analysis of the small subunit (SSU) rDNA. Morphologically, P. chlorelligerum differs from P. (Chloroparamecium) bursaria, the second green species in the genus, by having a special swimming shape, the length of the caudal cilia, the size of the micronucleus, the size of the symbiotic algae, the contractile vacuoles (with collecting vesicles vs. collecting canals), and the number of excretory pores /contractile vacuole (1 vs. 2--3). The molecular investigations show that P. chlorelligerum forms a distinct branch distant from the P. (Chloroparamecium) bursaria clade. Thus, we classify P. chlorelligerum in a new subgenus: Paramecium (Viridoparamecium) chlorelligerum. The symbiotic alga belongs to the little-known genus Meyerella, as yet recorded only from the plankton of a North American lake. PMID:22827482

  11. Is paramecium swimming autonomic?

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    Bandyopadhyay, Promode R.; Toplosky, Norman; Hansen, Joshua

    2010-11-01

    We seek to explore if the swimming of paramecium has an underlying autonomic mechanism. Such robotic elements may be useful in capturing the disturbance field in an environment in real time. Experimental evidence is emerging that motion control neurons of other animals may be present in paramecium as well. The limit cycle determined using analog simulation of the coupled nonlinear oscillators of olivo-cerebellar dynamics (ieee joe 33, 563-578, 2008) agrees with the tracks of the cilium of a biological paramecium. A 4-motor apparatus has been built that reproduces the kinematics of the cilium motion. The motion of the biological cilium has been analyzed and compared with the results of the finite element modeling of forces on a cilium. The modeling equates applied torque at the base of the cilium with drag, the cilium stiffness being phase dependent. A low friction pendulum apparatus with a multiplicity of electromagnetic actuators is being built for verifying the maps of the attractor basin computed using the olivo-cerebellar dynamics for different initial conditions. Sponsored by ONR 33.

  12. Morphological and molecular characterization of Paramecium (Viridoparamecium nov. subgen.) chlorelligerum Kahl (Ciliophora).

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    Kreutz, Martin; Stoeck, Thorsten; Foissner, Wilhelm

    2012-01-01

    We redescribe Paramecium chlorelligerum, a forgotten species, which Kahl (Tierwelt Dtl., 1935, 30:651) briefly but precisely described in the addendum to his ciliate monographs as a Paramecium with symbiotic green algae. The redescription is based on classical morphological methods and the analysis of the small subunit (SSU) rDNA. Morphologically, P. chlorelligerum differs from P. (C.) bursaria, the second green species in the genus, by having a special swimming shape, the length of the caudal cilia, the size of the micronucleus, the size of the symbiotic algae, the contractile vacuoles (with collecting vesicles vs. collecting canals), and the number of excretory pores/contractile vacuole (1 vs. 2-3). The molecular investigations show that P. chlorelligerum forms a distinct branch distant from the P. (Chloroparamecium) bursaria clade. Thus, we classify P. chlorelligerum in a new subgenus: Paramecium (Viridoparamecium) chlorelligerum. The symbiotic alga belongs to the little-known genus Meyerella, as yet recorded only from the plankton of a North American lake. © 2012 The Author(s) Journal of Eukaryotic Microbiology © 2012 International Society of Protistologists.

  13. Population Genomics of Paramecium Species.

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    Johri, Parul; Krenek, Sascha; Marinov, Georgi K; Doak, Thomas G; Berendonk, Thomas U; Lynch, Michael

    2017-05-01

    Population-genomic analyses are essential to understanding factors shaping genomic variation and lineage-specific sequence constraints. The dearth of such analyses for unicellular eukaryotes prompted us to assess genomic variation in Paramecium, one of the most well-studied ciliate genera. The Paramecium aurelia complex consists of ∼15 morphologically indistinguishable species that diverged subsequent to two rounds of whole-genome duplications (WGDs, as long as 320 MYA) and possess extremely streamlined genomes. We examine patterns of both nuclear and mitochondrial polymorphism, by sequencing whole genomes of 10-13 worldwide isolates of each of three species belonging to the P. aurelia complex: P. tetraurelia, P. biaurelia, P. sexaurelia, as well as two outgroup species that do not share the WGDs: P. caudatum and P. multimicronucleatum. An apparent absence of global geographic population structure suggests continuous or recent dispersal of Paramecium over long distances. Intergenic regions are highly constrained relative to coding sequences, especially in P. caudatum and P. multimicronucleatum that have shorter intergenic distances. Sequence diversity and divergence are reduced up to ∼100-150 bp both upstream and downstream of genes, suggesting strong constraints imposed by the presence of densely packed regulatory modules. In addition, comparison of sequence variation at non-synonymous and synonymous sites suggests similar recent selective pressures on paralogs within and orthologs across the deeply diverging species. This study presents the first genome-wide population-genomic analysis in ciliates and provides a valuable resource for future studies in evolutionary and functional genetics in Paramecium. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. L-glutamate Receptor In Paramecium

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    Bernal-Martínez, Juan; Ortega-Soto, Arturo

    2004-09-01

    Behavioral, electrophysiological and biochemical experiments were performed in order to establish the presence of a glutamate receptor in the ciliate Paramecium. It was found that an AMPA/KA receptor is functionally expressed in Paramecium and that this receptor is immunologically and fillogenetically related to the AMPA/KA receptor present in vertebrates.

  15. Forced symbiosis between Synechocystis spp. PCC 6803 and apo-symbiotic Paramecium bursaria as an experimental model for evolutionary emergence of primitive photosynthetic eukaryotes.

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    Ohkawa, Hiroshi; Hashimoto, Naoko; Furukawa, Shunsuke; Kadono, Takashi; Kawano, Tomonori

    2011-06-01

    Single-cell green paramecia (Paramecium bursaria) is a swimming vehicle that carries several hundred cells of endo-symbiotic green algae. Here, a novel model for endo-symbiosis, prepared by introducing and maintaining the cells of cyanobacterium (Synechocystis spp. PCC 6803) in the apo-symbiotic cells of P. bursaria is described.

  16. Analysis of amino acid and codon usage in Paramecium bursaria.

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    Dohra, Hideo; Fujishima, Masahiro; Suzuki, Haruo

    2015-10-07

    The ciliate Paramecium bursaria harbors the green-alga Chlorella symbionts. We reassembled the P. bursaria transcriptome to minimize falsely fused transcripts, and investigated amino acid and codon usage using the transcriptome data. Surface proteins preferentially use smaller amino acid residues like cysteine. Unusual synonymous codon and amino acid usage in highly expressed genes can reflect a balance between translational selection and other factors. A correlation of gene expression level with synonymous codon or amino acid usage is emphasized in genes down-regulated in symbiont-bearing cells compared to symbiont-free cells. Our results imply that the selection is associated with P. bursaria-Chlorella symbiosis. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  17. Rare Freshwater Ciliate Paramecium chlorelligerum Kahl, 1935 and Its Macronuclear Symbiotic Bacterium "Candidatus Holospora parva".

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    Olivia Lanzoni

    Full Text Available Ciliated protists often form symbioses with many diverse microorganisms. In particular, symbiotic associations between ciliates and green algae, as well as between ciliates and intracellular bacteria, are rather wide-spread in nature. In this study, we describe the complex symbiotic system between a very rare ciliate, Paramecium chlorelligerum, unicellular algae inhabiting its cytoplasm, and novel bacteria colonizing the host macronucleus. Paramecium chlorelligerum, previously found only twice in Germany, was retrieved from a novel location in vicinity of St. Petersburg in Russia. Species identification was based on both classical morphological methods and analysis of the small subunit rDNA. Numerous algae occupying the cytoplasm of this ciliate were identified with ultrastructural and molecular methods as representatives of the Meyerella genus, which before was not considered among symbiotic algae. In the same locality at least fifteen other species of "green" ciliates were found, thus it is indeed a biodiversity hot-spot for such protists. A novel species of bacterial symbionts living in the macronucleus of Paramecium chlorelligerum cells was morphologically and ultrastructurally investigated in detail with the description of its life cycle and infection capabilities. The new endosymbiont was molecularly characterized following the full-cycle rRNA approach. Furthermore, phylogenetic analysis confirmed that the novel bacterium is a member of Holospora genus branching basally but sharing all characteristics of the genus except inducing connecting piece formation during the infected host nucleus division. We propose the name "Candidatus Holospora parva" for this newly described species. The described complex system raises new questions on how these microorganisms evolve and interact in symbiosis.

  18. Rare Freshwater Ciliate Paramecium chlorelligerum Kahl, 1935 and Its Macronuclear Symbiotic Bacterium "Candidatus Holospora parva".

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    Lanzoni, Olivia; Fokin, Sergei I; Lebedeva, Natalia; Migunova, Alexandra; Petroni, Giulio; Potekhin, Alexey

    2016-01-01

    Ciliated protists often form symbioses with many diverse microorganisms. In particular, symbiotic associations between ciliates and green algae, as well as between ciliates and intracellular bacteria, are rather wide-spread in nature. In this study, we describe the complex symbiotic system between a very rare ciliate, Paramecium chlorelligerum, unicellular algae inhabiting its cytoplasm, and novel bacteria colonizing the host macronucleus. Paramecium chlorelligerum, previously found only twice in Germany, was retrieved from a novel location in vicinity of St. Petersburg in Russia. Species identification was based on both classical morphological methods and analysis of the small subunit rDNA. Numerous algae occupying the cytoplasm of this ciliate were identified with ultrastructural and molecular methods as representatives of the Meyerella genus, which before was not considered among symbiotic algae. In the same locality at least fifteen other species of "green" ciliates were found, thus it is indeed a biodiversity hot-spot for such protists. A novel species of bacterial symbionts living in the macronucleus of Paramecium chlorelligerum cells was morphologically and ultrastructurally investigated in detail with the description of its life cycle and infection capabilities. The new endosymbiont was molecularly characterized following the full-cycle rRNA approach. Furthermore, phylogenetic analysis confirmed that the novel bacterium is a member of Holospora genus branching basally but sharing all characteristics of the genus except inducing connecting piece formation during the infected host nucleus division. We propose the name "Candidatus Holospora parva" for this newly described species. The described complex system raises new questions on how these microorganisms evolve and interact in symbiosis.

  19. Swimming of Paramecium in confined channels

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    Jung, Sunghwan

    2012-02-01

    Many living organisms in nature have developed a few different swimming modes, presumably derived from hydrodynamic advantage. Paramecium is a ciliated protozoan covered by thousands of cilia with a few nanometers in diameter and tens of micro-meters in length and is able to exhibit both ballistic and meandering motions. First, we characterize ballistic swimming behaviors of ciliated microorganisms in glass capillaries of different diameters and explain the trajectories they trace out. We develop a theoretical model of an undulating sheet with a pressure gradient and discuss how it affects the swimming speed. Secondly, investigation into meandering swimmings within rectangular PDMS channels of dimension smaller than Paramecium length. We find that Paramecium executes a body-bend (an elastic buckling) using the cilia while it meanders. By considering an elastic beam model, we estimate and show the universal profile of forces it exerts on the walls. Finally, we discuss a few other locomotion of Paramecium in other extreme environments like gel.

  20. Synchronous induction of detachment and reattachment of symbiotic Chlorella spp. from the cell cortex of the host Paramecium bursaria.

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    Kodama, Yuuki; Fujishima, Masahiro

    2013-09-01

    Paramecium bursaria harbor several hundred symbiotic Chlorella spp. Each alga is enclosed in a perialgal vacuole membrane, which can attach to the host cell cortex. How the perialgal vacuole attaches beneath the host cell cortex remains unknown. High-speed centrifugation (> 1000×g) for 1min induces rapid detachment of the algae from the host cell cortex and concentrates the algae to the posterior half of the host cell. Simultaneously, most of the host acidosomes and lysosomes accumulate in the anterior half of the host cell. Both the detached algae and the dislocated acidic vesicles recover their original positions by host cyclosis within 10min after centrifugation. These recoveries were inhibited if the host cytoplasmic streaming was arrested by nocodazole. Endosymbiotic algae during the early reinfection process also show the capability of desorption after centrifugation. These results demonstrate that adhesion of the perialgal vacuole beneath the host cell cortex is repeatedly inducible, and that host cytoplasmic streaming facilitates recovery of the algal attachment. This study is the first report to illuminate the mechanism of the induction to desorb for symbiotic algae and acidic vesicles, and will contribute to the understanding of the mechanism of algal and organelle arrangements in Paramecium. Copyright © 2013 Elsevier GmbH. All rights reserved.

  1. Paramecium swimming in capillary tube

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    Jana, Saikat; Um, Soong Ho; Jung, Sunghwan

    2012-04-01

    Swimming organisms in their natural habitat need to navigate through a wide range of geometries and chemical environments. Interaction with boundaries in such situations is ubiquitous and can significantly modify the swimming characteristics of the organism when compared to ideal laboratory conditions. We study the different patterns of ciliary locomotion in glass capillaries of varying diameter and characterize the effect of the solid boundaries on the velocities of the organism. Experimental observations show that Paramecium executes helical trajectories that slowly transition to straight lines as the diameter of the capillary tubes decreases. We predict the swimming velocity in capillaries by modeling the system as a confined cylinder propagating longitudinal metachronal waves that create a finite pressure gradient. Comparing with experiments, we find that such pressure gradient considerations are necessary for modeling finite sized ciliary organisms in restrictive geometries.

  2. Programmed Rearrangement in Ciliates: Paramecium.

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    Betermier, Mireille; Duharcourt, Sandra

    2014-12-01

    Programmed genome rearrangements in the ciliate Paramecium provide a nice illustration of the impact of transposons on genome evolution and plasticity. During the sexual cycle, development of the somatic macronucleus involves elimination of ∼30% of the germline genome, including repeated DNA (e.g., transposons) and ∼45,000 single-copy internal eliminated sequences (IES). IES excision is a precise cut-and-close process, in which double-stranded DNA cleavage at IES ends depends on PiggyMac, a domesticated piggyBac transposase. Genome-wide analysis has revealed that at least a fraction of IESs originate from Tc/mariner transposons unrelated to piggyBac. Moreover, genomic sequences with no transposon origin, such as gene promoters, can be excised reproducibly as IESs, indicating that genome rearrangements contribute to the control of gene expression. How the system has evolved to allow elimination of DNA sequences with no recognizable conserved motif has been the subject of extensive research during the past two decades. Increasing evidence has accumulated for the participation of noncoding RNAs in epigenetic control of elimination for a subset of IESs, and in trans-generational inheritance of alternative rearrangement patterns. This chapter summarizes our current knowledge of the structure of the germline and somatic genomes for the model species Paramecium tetraurelia, and describes the DNA cleavage and repair factors that constitute the IES excision machinery. We present an overview of the role of specialized RNA interference machineries and their associated noncoding RNAs in the control of DNA elimination. Finally, we discuss how RNA-dependent modification and/or remodeling of chromatin may guide PiggyMac to its cognate cleavage sites.

  3. ACUTE TOXICITY OF METALS: NICKEL AND ZINC TO PARAMECIUM BURSARIA AND ITS ENDOSYMBIONTS

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    Patrycja Zagata

    2015-02-01

    Full Text Available Paramecium bursaria is an unicellular organism, widely distributed in the freshwater environment, where heavy metals are common contaminants. The ciliates, also including Paramecium bursaria, are a very abundant group in aquatic ecosystems, what makes them effective biological indicators of water pollutants. Paramecium bursaria is the only Paramecium which has evolved a mutualistic relationship with algae and it harbors these endosymbionts in its own cytoplasm. The algae are also very effective bioindicators of some pollutants because of their ability to biosorption and bioaccumulation of heavy metals. The aim of this study was to determine the acute toxicity of two metals’ compounds: nickel chloride (NiCl2 and zinc chloride (ZnCl2 to Paramecium bursaria and its endosymbionts. The ciliates were incubated in solutions with 5x10-8 to 5x10-2g/dm3 of NiCl2 and with 5x10-8 to 5x10-2g/dm3 of ZnCl2, at the temperature of 180C, in the light/dark conditions (12L/12D. Microscopic observations of cell divisions rate, cell shape changes as well as the swimming behavior, were conducted after 24, 48, 72 and 120 hours of incubation in the tested solutions and were compared to the control sample. Microscopic observations revealed the lethal doses for both compounds, for nickel chloride 5x10-5g/dm3 and for zinc chloride 5x10-3. These observations also revealed that in lesser concentrations than the lethal one, the slowdown and characteristic movements occur after metal addition. The PEA measurements of Fv/Fm parameter were carried out within 4 days, the first one after 24 hours of incubations. The results of this investigation has given us a view of a fluorescence efficiency by revealing that both compounds solutions can have the stimulating effect on Photosystem II, because the lowest fluorescence efficiency was measured in control samples.

  4. Orienting Paramecium with intense static magnetic fields

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    Valles, James M., Jr.; Guevorkian, Karine; Quindel, Carl

    2004-03-01

    Recent experiments on cell division suggest the application of intense static magnetic fields as a novel tool for the manipulation of biological systems [1]. The magnetic field appears to couple to the intrinsic anisotropies in the diamagnetic components of the cells. Here, we present measurements of the intrinsic average diamagnetic anisotropy of the whole single celled ciliate, Paramecium Caudatum. Magnetic fields, 2.5 T Paramecium Caudatum that were suspended in a density matched medium. The organisms align with their long axis parallel to the applied magnetic field. Their intrinsic diamagnetic anisotropy is 3x10-11 in cgs units. We will discuss the implications of these results for employing magnetic fields to probe the behavior of swimming Paramecium. [1] J. M. Valles, Jr. et al., Expt. Cell Res.274, 112-118 (2002).

  5. Homology-dependent Gene Silencing in Paramecium

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    Ruiz, Françoise; Vayssié, Laurence; Klotz, Catherine; Sperling, Linda; Madeddu, Luisa

    1998-01-01

    Microinjection at high copy number of plasmids containing only the coding region of a gene into the Paramecium somatic macronucleus led to a marked reduction in the expression of the corresponding endogenous gene(s). The silencing effect, which is stably maintained throughout vegetative growth, has been observed for all Paramecium genes examined so far: a single-copy gene (ND7), as well as members of multigene families (centrin genes and trichocyst matrix protein genes) in which all closely related paralogous genes appeared to be affected. This phenomenon may be related to posttranscriptional gene silencing in transgenic plants and quelling in Neurospora and allows the efficient creation of specific mutant phenotypes thus providing a potentially powerful tool to study gene function in Paramecium. For the two multigene families that encode proteins that coassemble to build up complex subcellular structures the analysis presented herein provides the first experimental evidence that the members of these gene families are not functionally redundant. PMID:9529389

  6. The mechanics of gravitaxis in Paramecium.

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    Roberts, A M

    2010-12-15

    An analysis of swimming patterns in the ciliate Paramecium shows that the ability to swim preferentially upwards (negative gravitaxis) is primarily the result of upwardly curving trajectories. The trajectory characteristics are consistent with those produced by mechanical orientation. Cell profile measurements from microscope images suggest that the characteristic front-rear body asymmetry accounts for the observed orientation rates. Gravikinesis may result from interactions between the propelling cilia and the sedimentary flow around the cell, and it seems unlikely that an internal physiological gravity receptor exists in Paramecium.

  7. Locomotion of Paramecium in patterned environments

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    Park, Eun-Jik; Eddins, Aja; Kim, Junil; Yang, Sung; Jana, Saikat; Jung, Sunghwan

    2011-10-01

    Ciliary organisms like Paramecium Multimicronucleatum locomote by synchronized beating of cilia that produce metachronal waves over their body. In their natural environments they navigate through a variety of environments especially surfaces with different topology. We study the effects of wavy surfaces patterned on the PDMS channels on the locomotive abilities of Paramecium by characterizing different quantities like velocity amplitude and wavelength of the trajectories traced. We compare this result with the swimming characteristics in straight channels and draw conclusions about the effects of various patterned surfaces.

  8. Paramecium swimming in a capillary tube

    Science.gov (United States)

    Jana, Saikat; Jung, Sunghwan

    2010-03-01

    Micro-organisms exhibit different strategies for swimming in complex environments. Many micro-swimmers such as paramecium congregate and tend to live near wall. We investigate how paramecium moves in a confined space as compared to its motion in an unbounded fluid. A new theoretical model based on Taylor's sheet is developed, to study such boundary effects. In experiments, paramecia are put inside capillary tubes and their swimming behavior is observed. The data obtained from experiments is used to test the validity of our theoretical model and understand how the cilia influence the locomotion of paramecia in confined geometries.

  9. Micro-particle transporting system using galvanotactically stimulated apo-symbiotic cells of Paramecium bursaria.

    Science.gov (United States)

    Furukawa, Shunsuke; Karaki, Chiaki; Kawano, Tomonori

    2009-01-01

    It is well known that Paramecium species including green paramecia (Paramecium bursaria) migrate towards the anode when exposed to an electric field in a medium. This type of a cellular movement is known as galvanotaxis. Our previous study revealed that an electric stimulus given to P bursaria is converted to a galvanotactic cellular movement by involvement of T-type calcium channel on the plasma membrane [Aonuma et al. (2007), Z. Naturforsch. 62c, 93-102]. This phenomenon has attracted the attention of bioengineers in the fields of biorobotics or micro-robotics in order to develop electrically controllable micromachineries. Here, we demonstrate the galvanotactic controls of the cellular migration of P bursaria in capillary tubes (diameter, 1-2 mm; length, 30-240 mm). Since the Paramecium cells take up particles of various sizes, we attempted to use the electrically stimulated cells of P bursaria as the vehicle for transportation of micro-particles in the capillary system. By using apo-symbiotic cells of P bursaria obtained after forced removal of symbiotic algae, the uptake of the particles could be maximized and visualized. Then, electrically controlled transportations of particle-filled apo-symbiotic P bursaria cells were manifested. The particles transported by electrically controlled cells (varying in size from nm to /m levels) included re-introduced green algae, fluorescence-labeled polystyrene beads, magnetic microspheres, emerald green fluorescent protein (EmGFP)-labeled cells of E. coli, Indian ink, and crystals of zeolite (hydrated aluminosilicate minerals with a micro-porous structure) and some metal oxides. Since the above demonstrations were successful, we concluded that P bursaria has a potential to be employed as one of the micro-biorobotic devices used in BioMEMS (biological micro-electro-mechanical systems).

  10. Paramecium: An Extensible Object-Based Kernel

    NARCIS (Netherlands)

    van Doorn, L.; Homburg, P.; Tanenbaum, A.S.

    1995-01-01

    In this paper we describe the design of an extensible kernel, called Paramecium. This kernel uses an object-based software architecture which together with instance naming, late binding and explicit overrides enables easy reconfiguration. Determining which components reside in the kernel protection

  11. The actin multigene family of Paramecium tetraurelia

    Directory of Open Access Journals (Sweden)

    Wagner Erika

    2007-03-01

    Full Text Available Abstract Background A Paramecium tetraurelia pilot genome project, the subsequent sequencing of a Megabase chromosome as well as the Paramecium genome project aimed at gaining insight into the genome of Paramecium. These cells display a most elaborate membrane trafficking system, with distinct, predictable pathways in which actin could participate. Previously we had localized actin in Paramecium; however, none of the efforts so far could proof the occurrence of actin in the cleavage furrow of a dividing cell, despite the fact that actin is unequivocally involved in cell division. This gave a first hint that Paramecium may possess actin isoforms with unusual characteristics. The genome project gave us the chance to search the whole Paramecium genome, and, thus, to identify and characterize probably all actin isoforms in Paramecium. Results The ciliated protozoan, P. tetraurelia, contains an actin multigene family with at least 30 members encoding actin, actin-related and actin-like proteins. They group into twelve subfamilies; a large subfamily with 10 genes, seven pairs and one trio with > 82% amino acid identity, as well as three single genes. The different subfamilies are very distinct from each other. In comparison to actins in other organisms, P. tetraurelia actins are highly divergent, with identities topping 80% and falling to 30%. We analyzed their structure on nucleotide level regarding the number and position of introns. On amino acid level, we scanned the sequences for the presence of actin consensus regions, for amino acids of the intermonomer interface in filaments, for residues contributing to ATP binding, and for known binding sites for myosin and actin-specific drugs. Several of those characteristics are lacking in several subfamilies. The divergence of P. tetraurelia actins and actin-related proteins between different P. tetraurelia subfamilies as well as with sequences of other organisms is well represented in a phylogenetic

  12. Rare Freshwater Ciliate Paramecium chlorelligerum Kahl, 1935 and Its Macronuclear Symbiotic Bacterium “Candidatus Holospora parva”

    Science.gov (United States)

    Lebedeva, Natalia; Migunova, Alexandra; Petroni, Giulio

    2016-01-01

    Ciliated protists often form symbioses with many diverse microorganisms. In particular, symbiotic associations between ciliates and green algae, as well as between ciliates and intracellular bacteria, are rather wide-spread in nature. In this study, we describe the complex symbiotic system between a very rare ciliate, Paramecium chlorelligerum, unicellular algae inhabiting its cytoplasm, and novel bacteria colonizing the host macronucleus. Paramecium chlorelligerum, previously found only twice in Germany, was retrieved from a novel location in vicinity of St. Petersburg in Russia. Species identification was based on both classical morphological methods and analysis of the small subunit rDNA. Numerous algae occupying the cytoplasm of this ciliate were identified with ultrastructural and molecular methods as representatives of the Meyerella genus, which before was not considered among symbiotic algae. In the same locality at least fifteen other species of “green” ciliates were found, thus it is indeed a biodiversity hot-spot for such protists. A novel species of bacterial symbionts living in the macronucleus of Paramecium chlorelligerum cells was morphologically and ultrastructurally investigated in detail with the description of its life cycle and infection capabilities. The new endosymbiont was molecularly characterized following the full-cycle rRNA approach. Furthermore, phylogenetic analysis confirmed that the novel bacterium is a member of Holospora genus branching basally but sharing all characteristics of the genus except inducing connecting piece formation during the infected host nucleus division. We propose the name “Candidatus Holospora parva” for this newly described species. The described complex system raises new questions on how these microorganisms evolve and interact in symbiosis. PMID:27992463

  13. Roll and Yaw of Paramecium swimming in a viscous fluid

    Science.gov (United States)

    Jung, Sunghwan; Jana, Saikat; Giarra, Matt; Vlachos, Pavlos

    2012-11-01

    Many free-swimming microorganisms like ciliates, flagellates, and invertebrates exhibit helical trajectories. In particular, the Paramecium spirally swims along its anterior direction by the beating of cilia. Due to the oblique beating stroke of cilia, the Paramecium rotates along its long axis as it swims forward. Simultaneously, this long axis turns toward the oral groove side. Combined roll and yaw motions of Paramecium result in swimming along a spiral course. Using Particle Image Velocimetry, we measure and quantify the flow field and fluid stress around Paramecium. We will discuss how the non-uniform stress distribution around the body induces this yaw motion.

  14. Effect of confinements: Bending in Paramecium

    Science.gov (United States)

    Eddins, Aja; Yang, Sung; Spoon, Corrie; Jung, Sunghwan

    2012-02-01

    Paramecium is a unicellular eukaryote which by coordinated beating of cilia, generates metachronal waves which causes it to execute a helical trajectory. We investigate the swimming parameters of the organism in rectangular PDMS channels and try to quantify its behavior. Surprisingly a swimming Paramecium in certain width of channels executes a bend of its flexible body (and changes its direction of swimming) by generating forces using the cilia. Considering a simple model of beam constrained between two walls, we predict the bent shapes of the organism and the forces it exerts on the walls. Finally we try to explain how bending (by sensing) can occur in channels by conducting experiments in thin film of fluid and drawing analogy to swimming behavior observed in different cases.

  15. soil algae

    African Journals Online (AJOL)

    Timothy Ademakinwa

    Also, the importance of algae in soil formation and soil fertility improvement cannot be over emphasized as the world is working ... farms further establishes the role of blue green algae in soil nutrients for plant growth. Key words- Soil Fertility, Soil ... with sunlight will promote the growth of soil algae and their contribution to ...

  16. Magnetic field influence on paramecium motility

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, M.F.; Rosen, A.D. (State Univ. of New York, Stony Brook (USA))

    1990-01-01

    The influence of a moderately intense static magnetic field on movement patterns of free swimming Paramecium was studied. When exposed to fields of 0.126 T, these ciliated protozoa exhibited significant reduction in velocity as well as a disorganization of movement pattern. It is suggested that these findings may be explained on the basis of alteration in function of ion specific channels within the cell membrane.

  17. Somersault of Paramecium in extremely confined environments

    Science.gov (United States)

    Jana, Saikat; Eddins, Aja; Spoon, Corrie; Jung, Sunghwan

    2015-08-01

    We investigate various swimming modes of Paramecium in geometric confinements and a non-swimming self-bending behavior like a somersault, which is quite different from the previously reported behaviors. We observe that Paramecia execute directional sinusoidal trajectories in thick fluid films, whereas Paramecia meander around a localized region and execute frequent turns due to collisions with adjacent walls in thin fluid films. When Paramecia are further constrained in rectangular channels narrower than the length of the cell body, a fraction of meandering Paramecia buckle their body by pushing on the channel walls. The bucking (self-bending) of the cell body allows the Paramecium to reorient its anterior end and explore a completely new direction in extremely confined spaces. Using force deflection method, we quantify the Young’s modulus of the cell and estimate the swimming and bending powers exerted by Paramecium. The analysis shows that Paramecia can utilize a fraction of its swimming power to execute the self-bending maneuver within the confined channel and no extra power may be required for this new kind of self-bending behavior. This investigation sheds light on how micro-organisms can use the flexibility of the body to actively navigate within confined spaces.

  18. Secondary structural analyses of ITS1 in Paramecium.

    Science.gov (United States)

    Hoshina, Ryo

    2010-01-01

    The nuclear ribosomal RNA gene operon is interrupted by internal transcribed spacer (ITS) 1 and ITS2. Although the secondary structure of ITS2 has been widely investigated, less is known about ITS1 and its structure. In this study, the secondary structure of ITS1 sequences for Paramecium and other ciliates was predicted. Each Paramecium ITS1 forms an open loop with three helices, A through C. Helix B was highly conserved among Paramecium, and similar helices were found in other ciliates. A phylogenetic analysis using the ITS1 sequences showed high-resolution, implying that ITS1 is a good tool for species-level analyses.

  19. The Study of Algae

    Science.gov (United States)

    Rushforth, Samuel R.

    1977-01-01

    Included in this introduction to the study of algae are drawings of commonly encountered freshwater algae, a summary of the importance of algae, descriptions of the seven major groups of algae, and techniques for collection and study of algae. (CS)

  20. Cell division and density of symbiotic Chlorella variabilis of the ciliate Paramecium bursaria is controlled by the host's nutritional conditions during early infection process.

    Science.gov (United States)

    Kodama, Yuuki; Fujishima, Masahiro

    2012-10-01

    The association of ciliate Paramecium bursaria with symbiotic Chlorella sp. is a mutualistic symbiosis. However, both the alga-free paramecia and symbiotic algae can still grow independently and can be reinfected experimentally by mixing them. Effects of the host's nutritional conditions against the symbiotic algal cell division and density were examined during early reinfection. Transmission electron microscopy revealed that algal cell division starts 24 h after mixing with alga-free P. bursaria, and that the algal mother cell wall is discarded from the perialgal vacuole membrane, which encloses symbiotic alga. Labelling of the mother cell wall with Calcofluor White Stain, a cell-wall-specific fluorochrome, was used to show whether alga had divided or not. Pulse labelling of alga-free P. bursaria cells with Calcofluor White Stain-stained algae with or without food bacteria for P. bursaria revealed that the fluorescence of Calcofluor White Stain in P. bursaria with bacteria disappeared within 3 days after mixing, significantly faster than without bacteria. Similar results were obtained both under constant light and dark conditions. This report is the first describing that the cell division and density of symbiotic algae of P. bursaria are controlled by the host's nutritional conditions during early infection. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  1. Methods for Studying Ciliary-Mediated Chemoresponse in Paramecium.

    Science.gov (United States)

    Valentine, Megan Smith; Van Houten, Judith L

    2016-01-01

    Paramecium is a useful model organism for the study of ciliary-mediated chemical sensing and response. Here we describe ways to take advantage of Paramecium to study chemoresponse.Unicellular organisms like the ciliated protozoan Paramecium sense and respond to chemicals in their environment (Van Houten, Ann Rev Physiol 54:639-663, 1992; Van Houten, Trends Neurosci 17:62-71, 1994). A thousand or more cilia that cover Paramecium cells serve as antennae for chemical signals, similar to ciliary function in a large variety of metazoan cell types that have primary or motile cilia (Berbari et al., Curr Biol 19(13):R526-R535, 2009; Singla V, Reiter J, Science 313:629-633, 2006). The Paramecium cilia also produce the motor output of the detection of chemical cues by controlling swimming behavior. Therefore, in Paramecium the cilia serve multiple roles of detection and response.We present this chapter in three sections to describe the methods for (1) assaying populations of cells for their behavioral responses to chemicals (attraction and repulsion), (2) characterization of the chemoreceptors and associated channels of the cilia using proteomics and binding assays, and (3) electrophysiological analysis of individual cells' responses to chemicals. These methods are applied to wild type cells, mutants, transformed cells that express tagged proteins, and cells depleted of gene products by RNA Interference (RNAi).

  2. Symbiotic Chlorella variabilis incubated under constant dark conditions for 24 hours loses the ability to avoid digestion by host lysosomal enzymes in digestive vacuoles of host ciliate Paramecium bursaria.

    Science.gov (United States)

    Kodama, Yuuki; Fujishima, Masahiro

    2014-12-01

    Endosymbiosis between symbiotic Chlorella and alga-free Paramecium bursaria cells can be induced by mixing them. To establish the endosymbiosis, algae must acquire temporary resistance to the host lysosomal enzymes in the digestive vacuoles (DVs). When symbiotic algae isolated from the alga-bearing paramecia are kept under a constant dark conditions for 24 h before mixing with the alga-free paramecia, almost all algae are digested in the host DVs. To examine the cause of algal acquisition to the host lysosomal enzymes, the isolated algae were kept under a constant light conditions with or without a photosynthesis inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea for 24 h, and were mixed with alga-free paramecia. Unexpectedly, most of the algae were not digested in the DVs irrespective of the presence of the inhibitor. Addition of 1 mM maltose, a main photosynthetic product of the symbiotic algae or of a supernatant of the isolated algae kept for 24 h under a constant light conditions, did not rescue the algal digestion in the DVs. These observations reveal that unknown factors induced by light are a prerequisite for algal resistance to the host lysosomal enzymes. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  3. Bioconvection and front formation of Paramecium tetraurelia

    Science.gov (United States)

    Kitsunezaki, So; Komori, Rie; Harumoto, Terue

    2007-10-01

    We have investigated the bioconvection of Paramecium tetraurelia in high-density suspensions made by centrifugal concentration. When a suspension is kept at rest in a Hele-Shaw cell, a crowded front of paramecia is formed in the vicinity of the bottom and it propagates gradually toward the water-air interface. Fluid convection occurs under this front, and it is driven persistently by the upward swimming of paramecia. The roll structures of the bioconvection become turbulent with an increase in the depth of the suspension; they also change rapidly as the density of paramecia increases. Our experimental results suggest that lack of oxygen in the suspension causes the active individual motions of paramecia to induce the formation of this front.

  4. Algae Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Algae are highly efficient at producing biomass, and they can be found all over the planet. Many use sunlight and nutrients to create biomass, which contain key components—including lipids, proteins, and carbohydrates— that can be converted and upgraded to a variety of biofuels and products. A functional algal biofuels production system requires resources such as suitable land and climate, sustainable management of water resources, a supplemental carbon dioxide (CO2) supply, and other nutrients (e.g., nitrogen and phosphorus). Algae can be an attractive feedstock for many locations in the United States because their diversity allows for highpotential biomass yields in a variety of climates and environments. Depending on the strain, algae can grow by using fresh, saline, or brackish water from surface water sources, groundwater, or seawater. Additionally, they can grow in water from second-use sources such as treated industrial wastewater; municipal, agricultural, or aquaculture wastewater; or produced water generated from oil and gas drilling operations.

  5. Simulation of Paramecium Chemotaxis Exposed to Calcium Gradients.

    Science.gov (United States)

    Sarvestani, Ali N; Shamloo, Amir; Ahmadian, Mohammad Taghi

    2016-06-01

    Paramecium or other ciliates have the potential to be utilized for minimally invasive surgery systems, making internal body organs accessible. Paramecium shows interesting responses to changes in the concentration of specific ions such as K(+), Mg(2+), and Ca(2+) in the ambient fluid. Some specific responses are observed as, changes in beat pattern of cilia and swimming toward or apart from the ion source. Therefore developing a model for chemotactic motility of small organisms is necessary in order to control the directional movements of these microorganisms before testing them. In this article, we have developed a numerical model, investigating the effects of Ca(2+) on swimming trajectory of Paramecium. Results for Ca(2+)-dependent chemotactic motility show that calcium gradients are efficient actuators for controlling the Paramecium swimming trajectory. After applying a very low Ca(2+) gradient, a directional chemotaxis of swimming Paramecium is observable in this model. As a result, chemotaxis is shown to be an efficient method for controlling the propulsion of these small organisms.

  6. Survey of Paramecium duboscqui using three markers and assessment of the molecular variability in the genus Paramecium.

    Science.gov (United States)

    Boscaro, Vittorio; Fokin, Sergei I; Verni, Franco; Petroni, Giulio

    2012-12-01

    The genus Paramecium (phylum Ciliophora) is one of the best-known among protozoa. Nevertheless, the knowledge on the diversity and distribution of species within this genus was remarkably scarce until recent times. In the last years a constantly growing amount of data has formed, especially on the distribution of species and the characterization of molecular markers. Much effort has been made on detecting clades inside each morphospecies, which could suggest the presence of sibling species complexes as in the famous case of Paramecium aurelia. In this work we present new data on Paramecium duboscqui, one of the morphospecies that have not yet been surveyed employing DNA sequences as markers. We obtained data from nine strains sampled around the world, using the three most commonly employed markers (18S rRNA gene, ITS1-5.8S-ITS2 and COI gene sequences). Moreover, we compared our results with those already available for other Paramecium species, and performed phylogenetic analyses for the entire genus. We also expanded the knowledge on the ITS2 secondary structure and its usefulness in studies on Paramecium. Our approach, that considers the data of all the species together, highlighted some characteristic patterns as well as some ambiguities that should be further investigated. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Cell proliferation of Paramecium tetraurelia on a slow rotating clinostat

    Science.gov (United States)

    Sawai, Satoe; Mogami, Yoshihiro; Baba, Shoji A.

    Paramecium is known to proliferate faster under microgravity conditions, and slower under hypergravity. Experiments using axenic culture medium have demonstrated that hypergravity affected directly on the proliferation of Paramecium itself. In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation, Paramecium tetraurelia was grown under clinorotation (2.5 rpm) and the time course of the proliferation was investigated in detail on the basis of the logistic analysis. On the basis of the mechanical properties of Paramecium, this slow rate of the rotation appears to be enough to simulate microgravity in terms of the randomization of the cell orientation with respect to gravity. P. tetraurelia was cultivated in a closed chamber in which cells were confined without air bubbles, reducing the shear forces and turbulences under clinorotation. The chamber is made of quartz and silicone rubber film; the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method, and the latter for gas exchange. Because of the small dimension for culture space, Paramecium does not accumulate at the top of the chamber in spite of its known negative gravitactic behavior. We measured the cell density at regular time intervals without breaking the configuration of the chamber, and analyzed the proliferation parameters by fitting the data to a logistic equation. As a result, P. tetraurelia showed reduced proliferation under slow clinorotation. The saturation of the cell density as well as the maximum proliferation rate decreased, although we found no significant changes on the half maximal time for proliferation. We also found that the mean swimming velocity decreased under slow clinorotation. These results were not consistent with those under microgravity and fast rotating clinostat. This may suggest that randomization of the cell orientation performed by slow rotating clinostat has

  8. Pb2+ Modulates Ca2+ Membrane Permeability In Paramecium

    Science.gov (United States)

    Bernal-Martínez, Juan; Ortega Soto, Arturo

    2004-09-01

    Intracellular recording experiments in current clamp configuration were done to evaluate whether Pb2+ modulates ionic membrane permeability in the fresh water Paramecium tetraurelia. It was found that Pb2+ triggers in a dose-dependent manner, a burst of spontaneous action potentials followed by a robust and sustained after hyper-polarization. In addition, Pb2+ increased the frequency of firing the spontaneous Ca2+-Action Potential and also, the duration of Ca2+-Action Potential, in a dose and reversibly-dependent manner. These results suggest that Pb2+ increases calcium membrane permeability of Paramecium and probably activates a calcium-dependent-potassium conductance in the ciliate.

  9. Calcium transport across the membrane of Paramecium caudatum (protozoa)

    International Nuclear Information System (INIS)

    Martinac, B.

    1980-06-01

    Calcium transport across the membrane of Paramecium caudatum was studied by measuring calcium uptake and release by means of flow-through-technique, which was developed especially for this purpose. The method allows continuous flow of the cells suspension with radioactive and inactive solution, respectively, combined with simultaneous electrical stimulation of the cells by means of extracellular electrodes. The results obtained were compared to and interpreted according to behavioral patterns of Paramecium, which were registered by the time exposure dark-field macrophotographic technique under the same experimental conditions. (orig.) [de

  10. Particle sorting by Paramecium cilia arrays.

    Science.gov (United States)

    Mayne, Richard; Whiting, James G H; Wheway, Gabrielle; Melhuish, Chris; Adamatzky, Andrew

    Motile cilia are cell-surface organelles whose purposes, in ciliated protists and certain ciliated metazoan epithelia, include generating fluid flow, sensing and substance uptake. Certain properties of cilia arrays, such as beating synchronisation and manipulation of external proximate particulate matter, are considered emergent, but remain incompletely characterised despite these phenomena having being the subject of extensive modelling. This study constitutes a laboratory experimental characterisation of one of the emergent properties of motile cilia: manipulation of adjacent particulates. The work demonstrates through automated videomicrographic particle tracking that interactions between microparticles and somatic cilia arrays of the ciliated model organism Paramecium caudatum constitute a form of rudimentary 'sorting'. Small particles are drawn into the organism's proximity by cilia-induced fluid currents at all times, whereas larger particles may be held immobile at a distance from the cell margin when the cell generates characteristic feeding currents in the surrounding media. These findings can contribute to the design and fabrication of biomimetic cilia, with potential applications to the study of ciliopathies. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Cell proliferation of Paramecium tetraurelia under simulated microgravity

    Science.gov (United States)

    Sawai, S.; Mogami, Y.; Baba, S. A.

    Paramecium is known to proliferate faster under microgravity in space and slower under hypergravity Experiments using axenic culture medium have demonstrated that the hypergravity affected directly on the proliferation of Paramecium itself Kato et al 2003 In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation Paramecium tetraurelia was grown under simulated microgravity performed by clinorotation and the time course of the proliferation was investigated in detail on the basis of the logistic analysis P tetraurelia was cultivated in a closed chamber in which cells were confined without air babbles reducing the shear stresses and turbulence under the rotation The chamber is made of quartz and silicone rubber film the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method and the latter for gas exchange Because the closed chamber has an inner dimension of 3 times 3 times 60 mm Paramecium does not accumulate at the top of the chamber despite its negative gravitactic behavior We measured the cell density at regular time intervals without breaking the configuration of the chamber and analyzed the proliferation parameters by fitting the data to a logistic equation Clinorotation had the effects of reducing the proliferation of P tetraurelia It reduced both the saturation cell density and the maximum proliferation rate although it had little effect on the

  12. Remembrance of things past retrieved from the Paramecium genome.

    Science.gov (United States)

    Sperling, Linda

    2011-01-01

    Paramecium and other ciliates are the only unicellular eukaryotes that separate germinal and somatic functions. A germline micronucleus transmits the genetic information to sexual progeny, while a somatic macronucleus expresses the genetic information during vegetative growth to determine the phenotype. At each sexual generation, a new macronucleus develops from the zygotic nucleus through programmed rearrangements of the germline genome. Paramecium tetraurelia somatic genome sequencing, reviewed here, has provided insight into the organization and evolution of the genome. A series of at least 3 whole genome duplications was detected in the Paramecium lineage and selective pressures that determine the fate of the gene duplicates analyzed. Variability in the somatic DNA was characterized and could be attributed to the genome rearrangement processes. Since, in Paramecium, alternative genome rearrangement patterns can be inherited across sexual generations by homology-dependent epigenetic mechanisms and can affect phenotype, I discuss the possibility that ciliate nuclear dimorphism buffers genetic variation hidden in the germline. Copyright © 2011 Institut Pasteur. Published by Elsevier SAS. All rights reserved.

  13. Biological effect of paramecium in diffused ultrasonic fields.

    Science.gov (United States)

    Yang, Shiuh-Kuang; Huang, Yi-Cheng

    2002-04-01

    Since the cell structure or biophysical reaction includes in the interaction between ultrasound and living matter. When multi-cell creature is exposed to ultrasound, this reaction will lead the biological effect becomes complex. Therefore, in this paper, a single cell creature is chosen to study the biological effects induced by ultrasound exposure. The paramecium, which possesses many features typical of higher-order animal cells, was considered an appropriate choice for this study. The ability shown by ultrasound in promoting and/or accelerating many reactions has been shown to be a useful field. The growth phase of paramecium by using the ultrasound irradiation is an important parameter in this study. In our experiment, the exponential and stationary phases were employed. Three important factors must be taken into account when an ultrasonic biological reaction is investigated: the medium system, the bubbles' field, and the acoustic field. The medium system involves the physical parameters of the medium field. The bubbles' field includes the reacting bubble size of the liquid and the resonance frequency of the reaction bubbles. The oscillation of the cells in response to the ultrasound radiation is simulated using Rayleigh-Plesset's bubble activation theory. The resonance frequency of the unicellular creature is then calculated. The acoustic field is about using the diffuse field theory of Sabine to create a uniform sound field for the radiation experiment. The resonance frequency of the paramecium vacuole is among 0.54-1.09 MHz. When the 0.25 and 0.5 MHz frequencies of ultrasound was irradiated in the stationary phase of the paramecium, the relative growth rate was about 20% lower than that of unexposed sample. Therefore, the phenomenon of inhibition and destruction appeared during irradiation. The exponential phase of the paramecium samples appear to be different when irradiated with 1 MHz ultrasound. As can be seen in the results, the maximum relative growth

  14. Surface interactions affect the toxicity of engineered metal oxide nanoparticles toward Paramecium.

    Science.gov (United States)

    Li, Kungang; Chen, Ying; Zhang, Wen; Pu, Zhichao; Jiang, Lin; Chen, Yongsheng

    2012-08-20

    To better understand the potential impacts of engineered metal oxide nanoparticles (NPs) in the ecosystem, we investigated the acute toxicity of seven different types of engineered metal oxide NPs against Paramecium multimicronucleatum, a ciliated protozoan, using the 48 h LC(50) (lethal concentration, 50%) test. Our results showed that the 48 h LC(50) values of these NPs to Paramecium ranged from 0.81 (Fe(2)O(3) NPs) to 9269 mg/L (Al(2)O(3) NPs); their toxicity to Paramecium increased as follows: Al(2)O(3) Paramecium; this implies that metal oxide NPs with strong association with the cell surface might induce more severe cytotoxicity in unicellular organisms.

  15. Assessing phagotrophy in the mixotrophic ciliate Paramecium bursaria using GFP-expressing yeast cells.

    Science.gov (United States)

    Miura, Takashi; Moriya, Hisao; Iwai, Sosuke

    2017-07-03

    We used cells of the yeast Saccharomyces cerevisiae expressing green fluorescent protein (GFP) as fluorescently labelled prey to assess the phagocytic activities of the mixotrophic ciliate Paramecium bursaria, which harbours symbiotic Chlorella-like algae. Because of different fluorescence spectra of GFP and algal chlorophyll, ingested GFP-expressing yeast cells can be distinguished from endosymbiotic algal cells and directly counted in individual P. bursaria cells using fluorescence microscopy. By using GFP-expressing yeast cells, we found that P. bursaria altered ingestion activities under different physiological conditions, such as different growth phases or the presence/absence of endosymbionts. Use of GFP-expressing yeast cells allowed us to estimate the digestion rates of live prey of the ciliate. In contrast to the ingestion activities, the digestion rate within food vacuoles was not affected by the presence of endosymbionts, consistent with previous findings that food and perialgal vacuoles are spatially and functionally separated in P. bursaria. Thus, GFP-expressing yeast may provide a valuable tool to assess both ingestion and digestion activities of ciliates that feed on eukaryotic organisms. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Induction of Maltose Release by Light in the Endosymbiont Chlorella variabilis of Paramecium bursaria.

    Science.gov (United States)

    Shibata, Aika; Takahashi, Fumio; Kasahara, Masahiro; Imamura, Nobutaka

    2016-11-01

    The endosymbiotic green algae of Paramecium bursaria are known to release a photosynthate to the host cells. The endosymbiont Chlorella variabilis F36-ZK isolated in Japan releases maltose under acidic conditions, and such release requires both light and low pH. However, whether photosynthate release is due to light sensing by photoreceptors or is merely a consequence of active photosynthesis is unclear. Herein, we studied the effect of light on maltose release from C. variabilis F36-ZK; we measured maltose release using a combination of 1-phenyl-3-methyl-5-pyrazolone derivative and 14 C-tracer methods. Blue (450nm) or red (around 600nm) light was most effective to stimulate maltose release. This suggests that the photosynthetic pathway probably participates in maltose release, because the effective wavelength corresponds to the absorption spectrum of chlorophyll. Furthermore, maltose release was slightly affected by addition of a photosynthetic inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, but was abolished by another inhibitor of photosynthesis, 2,5-dibromo-6-isopropyl-3-methyl-1,4-benzoquinone, suggesting that electron flow through photosystem I may be more involved in maltose release. Interestingly, starving F36-ZK cells cultured under prolonged dark conditions did not release maltose but retained their photosynthetic capacity. Our results thus show that maltose release is regulated by light and cellular conditions in endosymbiotic Chlorella. Copyright © 2016. Published by Elsevier GmbH.

  17. Detecting the gravitational sensitivity of Paramecium caudatum using magnetic forces

    Science.gov (United States)

    Guevorkian, Karine; Valles, James M., Jr.

    2006-03-01

    Under normal conditions, Paramecium cells regulate their swimming speed in response to the pN level mechanical force of gravity. This regulation, known as gravikinesis, is more pronounced when the external force is increased by methods such as centrifugation. Here we present a novel technique that simulates gravity fields using the interactions between strong inhomogeneous magnetic fields and cells. We are able to achieve variable gravities spanning from 10xg to -8xg; where g is earth's gravity. Our experiments show that the swimming speed regulation of Paramecium caudatum to magnetically simulated gravity is a true physiological response. In addition, they reveal a maximum propulsion force for paramecia. This advance establishes a general technique for applying continuously variable forces to cells or cell populations suitable for exploring their force transduction mechanisms.

  18. Species Identity of Commercial Stocks of Paramecium in the U.S.

    Science.gov (United States)

    Cole, Thomas A.; And Others

    1992-01-01

    Describes how paramecium can be identified through the use of DNA-binding fluorescent compounds. The authors used these techniques to test the paramecium stocks from 12 commercial sources. The details of the staining procedures and the results of the commercial tests are presented in this article. (PR)

  19. Research on Paramecium aurelia sensitivity factors to natural ionizing radiations

    International Nuclear Information System (INIS)

    Croute, F.; Soleilhavoup, J.P.; Gros, N.; Planel, H.

    1976-01-01

    Previous results have demonstrated that the proliferative activity of Paramecium aurelia is linked to the level of natural ionizing radiations since this activity is decreased under radiation protection (lead cell) and increased under chronic exposure to very low dose of 60 Co gamma rays. The results of this investigation indicate that cell sensitivity in spite of variations in natural irradiation levels can be isolated; they are called 'radioresistant' in opposition to 'radiosensitive' cells which present the other response. These characters are being retained for 9 months after the strains have been isolated. On the other hand, in the case of radiosensitive strains, it has been demonstrated that autogamy affected the cell response to background irradiation; no response at all occured on the very day when autogamy took place, but it reached a maximum level 8 days approximately after autogamy. Moreover, it has been proved that the catalase activity of Paramecium aurelia is higher than those already studied in other cell varieties. This great amount of catalase, which seems to vary with the age of cultures after autogamy, could act on Paramecium sensitivity to very low radiation doses [fr

  20. Transitions between three swimming gaits in Paramecium escape.

    Science.gov (United States)

    Hamel, Amandine; Fisch, Cathy; Combettes, Laurent; Dupuis-Williams, Pascale; Baroud, Charles N

    2011-05-03

    Paramecium and other protists are able to swim at velocities reaching several times their body size per second by beating their cilia in an organized fashion. The cilia beat in an asymmetric stroke, which breaks the time reversal symmetry of small scale flows. Here we show that Paramecium uses three different swimming gaits to escape from an aggression, applied in the form of a focused laser heating. For a weak aggression, normal swimming is sufficient and produces a steady swimming velocity. As the heating amplitude is increased, a higher acceleration and faster swimming are achieved through synchronized beating of the cilia, which begin by producing oscillating swimming velocities and later give way to the usual gait. Finally, escape from a life-threatening aggression is achieved by a "jumping" gait, which does not rely on the cilia but is achieved through the explosive release of a group of trichocysts in the direction of the hot spot. Measurements through high-speed video explain the role of trichocysts in defending against aggressions while showing unexpected transitions in the swimming of microorganisms. These measurements also demonstrate that Paramecium optimizes its escape pattern by taking advantage of its inertia.

  1. A two-locus molecular characterization of Paramecium calkinsi.

    Science.gov (United States)

    Przyboś, Ewa; Tarcz, Sebastian; Potekhin, Alexey; Rautian, Maria; Prajer, Małgorzata

    2012-03-01

    Paramecium calkinsi (Ciliophora, Protozoa) is a euryhaline species which was first identified in freshwater habitats, but subsequently several strains were also collected from brackish water. It is characterized by clockwise spiral swimming movement and the general morphology of the "bursaria type." The present paper is the first molecular characterization of P. calkinsi strains recently collected in distant regions in Russia using ITS1-5.8S- ITS2-5'LSU rDNA (1100bp) and COI (620bp) mtDNA sequenced gene fragments. For comparison, our molecular analysis includes P. bursaria, exhibiting a similar "bursaria morphotype" as well as species representing the "aurelia type," i.e., P. caudatum, P. multimicronucleatum, P. jenningsi, and P. schewiakoffi, and some species of the P. aurelia species complex (P. primaurelia, P. tetraurelia, P. sexaurelia, and P. tredecaurelia). We also use data from GenBank concerning other species in the genus Paramecium and Tetrahymena (which used as an outgroup). The division of the genus Paramecium into four subgenera (proposed by Fokin et al. 2004) is clearly presented by the trees. There is a clear separation between P. calkinsi strains collected from different regions (races). Consequently, given the molecular distances between them, it seems that these races may represent different syngens within the species. Copyright © 2011 Elsevier GmbH. All rights reserved.

  2. Ciliary heterogeneity within a single cell: the Paramecium model.

    Science.gov (United States)

    Aubusson-Fleury, Anne; Cohen, Jean; Lemullois, Michel

    2015-01-01

    Paramecium is a single cell able to divide in its morphologically differentiated stage that has many cilia anchored at its cell surface. Many thousands of cilia are thus assembled in a short period of time during division to duplicate the cell pattern while the cell continues swimming. Most, but not all, of these sensory cilia are motile and involved in two main functions: prey capture and cell locomotion. These cilia display heterogeneity, both in their length and their biochemical properties. Thanks to these properties, as well as to the availability of many postgenomic tools and the possibility to follow the regrowth of cilia after deciliation, Paramecium offers a nice opportunity to study the assembly of the cilia, as well as the genesis of their diversity within a single cell. In this paper, after a brief survey of Paramecium morphology and cilia properties, we describe the tools and the protocols currently used for immunofluorescence, transmission electron microscopy, and ultrastructural immunocytochemistry to analyze cilia, with special recommendations to overcome the problem raised by cilium diversity. Copyright © 2015. Published by Elsevier Inc.

  3. Effects of perfluorinated amphiphiles on backward swimming in Paramecium caudatum

    International Nuclear Information System (INIS)

    Matsubara, Eriko; Harada, Kouji; Inoue, Kayoko; Koizumi, Akio

    2006-01-01

    PFOS and PFOA are ubiquitous contaminants in the environment. We investigated the effects of fluorochemicals on calcium currents in Paramecium caudatum using its behavioral changes. Negatively charged amphiphiles prolonged backward swimming (BWS) of Paramecium. PFOS significantly prolonged BWS, while PFOA was less potent (EC 5 : 29.8 ± 4.1 and 424.1 ± 124.0 μM, respectively). The BWS prolongation was blocked by cadmium, indicating that the cellular calcium conductance had been modified. The positively charged amphiphile FOSAPrTMA shortened BWS (EC 5 : 19.1 ± 17.3). Nonionic amphiphiles did not affect BWS. The longer-chain perfluorinated carboxylates PFNA and PFDA were more potent than PFOA (EC 5 : 98.7 ± 20.1 and 60.4 ± 10.1 μM, respectively). However, 1,8-perfluorooctanedioic acid and 1,10-perfluorodecanedioic acid did not prolong BWS. The critical micelle concentration (CMC) and BWS prolongation for negatively charged amphiphiles showed a clear correlation (r 2 = 0.8008, p < 0.001). In summary, several perfluorochemicals and PFOS and PFOA had similar effects in Paramecium, while chain length, CMC, and electric charge were major determinants of BWS duration

  4. Fine oral filaments in Paramecium: a biochemical and immunological analysis.

    Science.gov (United States)

    Clerot, J; Iftode, F; Budin, K; Jeanmaire-Wolf, R; Coffe, G; Fleury-Aubusson, A

    2001-01-01

    In Paramecium, several kinds of the oral networks of fine filaments are defined at the ultrastructural level. Using the sodium chloride-treated oral apparatus of Paramecium as an antigen to produce monoclonal antibodies, we have begun to identify the proteins constituting these networks. Immunoblotting showed that all positive antibodies were directed against three bands (70-, 75-and 83-kD), which corresponded to quantitatively minor components of the antigen; there was no antibody specific for the quantitatively major components (58- and 62-kD). Immunolocalization with four of these antibodies directed against one or several of these three bands showed that these proteins are components of the fine filaments supporting the oral area; a decoration of the basal bodies and the outer lattice was also observed on the cortex. Immunofluorescence on interphase cells suggested that the three proteins colocalized on the left side of the oral apparatus, whereas only the 70-kD band was detected on the right side. During division, the antigens of the antibodies were detected at different stages after oral basal body assembly. The antibodies cross-reacted with the tetrins, which are oral filament-forming proteins in Tetrahymena, demonstrating that tetrin-related proteins are quantitatively minor components of the oral and the somatic cytoskeleton of Paramecium.

  5. Responses triggered in chloroplast of Chlorella variabilis NC64A by long-term association with Paramecium bursaria.

    Science.gov (United States)

    Minaeva, Ekaterina; Ermilova, Elena

    2017-07-01

    The unicellular green alga Chlorella variabilis NC64A is an endosymbiont of the ciliate Paramecium bursaria. The host's control, including the transfer of biochemical substrates from P. bursaria to C. variabilis, is involved in symbiotic relationships. C. variabilis NC64A that had been re-infected to P. bursaria for more than 1 year and isolated from the host showed higher chlorophyll levels compared to those in free-living cells. Unlike the host, the expression of C. variabilis NC64A heat shock 70 kDa protein was independent of establishment of endosymbiosis. In symbiotic cells, the levels of PII signal transduction protein (CvPII) that coordinate the central C/N anabolic metabolism were slightly higher than those in free-living cells. Furthermore, the environmental cues (light and host food bacteria availability) affected the abundance of CvPII, suggesting that synthesis of the protein was influenced by the host. Moreover, arginine concentrations in the symbiotic algae of P. bursaria were also controlled by the host's nutritional conditions. Together, our results imply that signal substrates and/or products of metabolism in host cells might act as messengers mediating the regulation of key events in symbiont cells.

  6. Deep RNA sequencing reveals hidden features and dynamics of early gene transcription in Paramecium bursaria chlorella virus 1.

    Directory of Open Access Journals (Sweden)

    Guillaume Blanc

    Full Text Available Paramecium bursaria chlorella virus 1 (PBCV-1 is the prototype of the genus Chlorovirus (family Phycodnaviridae that infects the unicellular, eukaryotic green alga Chlorella variabilis NC64A. The 331-kb PBCV-1 genome contains 416 major open reading frames. A mRNA-seq approach was used to analyze PBCV-1 transcriptomes at 6 progressive times during the first hour of infection. The alignment of 17 million reads to the PBCV-1 genome allowed the construction of single-base transcriptome maps. Significant transcription was detected for a subset of 50 viral genes as soon as 7 min after infection. By 20 min post infection (p.i., transcripts were detected for most PBCV-1 genes and transcript levels continued to increase globally up to 60 min p.i., at which time 41% or the poly (A+-containing RNAs in the infected cells mapped to the PBCV-1 genome. For some viral genes, the number of transcripts in the latter time points (20 to 60 min p.i. was much higher than that of the most highly expressed host genes. RNA-seq data revealed putative polyadenylation signal sequences in PBCV-1 genes that were identical to the polyadenylation signal AAUAAA of green algae. Several transcripts have an RNA fragment excised. However, the frequency of excision and the resulting putative shortened protein products suggest that most of these excision events have no functional role but are probably the result of the activity of misled splicesomes.

  7. Longevity of a Paramecium cell clone in space: Hypergravity experiments as a basis for microgravity experiments

    Science.gov (United States)

    Kato, Yuko; Mogami, Yoshihiro; Baba, Shoji A.

    We proposed a space experiment aboard International Space Station to explore the effects of microgravity on the longevity of a Paramecium cell clone. Earlier space experiments in CYTOS and Space Lab D-1 demonstrated that Paramecium proliferated faster in space. In combination with the fact that aging process in Paramecium is largely related to the fission age, the results of the proliferation experiment in space may predict that the longevity of Paramecium decreases when measured by clock time. In preparation of the space experiment, we assessed the aging process under hypergravity, which is known to reduce the proliferation rate. As a result, the length of autogamy immaturity increased when measured by clock time, whereas it remained unchanged by fission age. It is therefore expected that autogamy immaturity in the measure of the clock time would be shortened under microgravity. Since the length of clonal life span of Paramecium is related to the length of autogamy immaturity, the result of hypergravity experiment supports the prediction that the clonal longevity of Paramecium under microgravity decreases. Effects of gravity on proliferation are discussed in terms of energetics of swimming during gravikinesis and gravitaxis of Paramecium.

  8. Anesthetic action of volatile anesthetics by using Paramecium as a model.

    Science.gov (United States)

    Zhou, Miaomiao; Xia, Huimin; Xu, Younian; Xin, Naixing; Liu, Jiao; Zhang, Shihai

    2012-06-01

    Although empirically well understood in their clinical administration, volatile anesthetics are not yet well comprehended in their mechanism studies. A major conundrum emerging from these studies is that there is no validated model to assess the presumed candidate sites of the anesthetics. We undertook this study to test the hypothesis that the single-celled Paramecium could be anesthetized and served as a model organism in the study of anesthetics. We assessed the motion of Paramecium cells with Expert Vision system and the chemoresponse of Paramecium cells with T-maze assays in the presence of four different volatile anesthetics, including isoflurane, sevoflurane, enflurane and ether. Each of those volatiles was dissolved in buffers to give drug concentrations equal to 0.8, 1.0, and 1.2 EC50, respectively, in clinical practice. We could see that after application of volatile anesthetics, the swimming of the Paramecium cells was accelerated and then suppressed, or even stopped eventually, and the index of the chemoresponse of the Paramecium cells (denoted as I ( che )) was decreased. All of the above impacts were found in a concentration-dependent fashion. The biphasic effects of the clinical concentrations of volatile anesthetics on Paramecium simulated the situation of high species in anesthesia, and the inhibition of the chemoresponse also indicated anesthetized. In conclusion, the findings in our studies suggested that the single-celled Paramecium could be anesthetized with clinical concentrations of volatile anesthetics and therefore be utilized as a model organism to study the mechanisms of volatile anesthetics.

  9. Magnetic separation of algae

    Science.gov (United States)

    Nath, Pulak; Twary, Scott N.

    2016-04-26

    Described herein are methods and systems for harvesting, collecting, separating and/or dewatering algae using iron based salts combined with a magnetic field gradient to separate algae from an aqueous solution.

  10. Voltage-gated calcium channels of Paramecium cilia.

    Science.gov (United States)

    Lodh, Sukanya; Yano, Junji; Valentine, Megan S; Van Houten, Judith L

    2016-10-01

    Paramecium cells swim by beating their cilia, and make turns by transiently reversing their power stroke. Reversal is caused by Ca 2+ entering the cilium through voltage-gated Ca 2+ (Ca V ) channels that are found exclusively in the cilia. As ciliary Ca 2+ levels return to normal, the cell pivots and swims forward in a new direction. Thus, the activation of the Ca V channels causes cells to make a turn in their swimming paths. For 45 years, the physiological characteristics of the Paramecium ciliary Ca V channels have been known, but the proteins were not identified until recently, when the P. tetraurelia ciliary membrane proteome was determined. Three Ca V α1 subunits that were identified among the proteins were cloned and confirmed to be expressed in the cilia. We demonstrate using RNA interference that these channels function as the ciliary Ca V channels that are responsible for the reversal of ciliary beating. Furthermore, we show that Pawn (pw) mutants of Paramecium that cannot swim backward for lack of Ca V channel activity do not express any of the three Ca V 1 channels in their ciliary membrane, until they are rescued from the mutant phenotype by expression of the wild-type PW gene. These results reinforce the correlation of the three Ca V channels with backward swimming through ciliary reversal. The PwB protein, found in endoplasmic reticulum fractions, co-immunoprecipitates with the Ca V 1c channel and perhaps functions in trafficking. The PwA protein does not appear to have an interaction with the channel proteins but affects their appearance in the cilia. © 2016. Published by The Company of Biologists Ltd.

  11. Pharmacological attenuation of Paramecium fluid-phase endocytosis.

    Science.gov (United States)

    Wiejak, Jolanta; Surmacz, Liliana; Wyroba, Elzbieta

    2007-01-01

    Spectrophotometric quantification of fluid phase endocytosis in the presence of different pharmacological compounds was performed in the model unicellular eukaryote Paramecium. The kinetics of Lucifer Yellow Carbohydrazide (LY) uptake in cells exposed to forskolin and isoproterenol--known to stimulate phagocytosis in this cell--was analyzed. Reduction in both the rate of endocytosis and total accumulation of fluid phase marker was observed following the treatment. Forskolin diminished total LY accumulation by 11% and 21% after 5 min and 25 min of incubation, respectively, whereas the rate of uptake was lowered by 21% in comparison to control cells. The inhibitory effect ofisoproterenol was less pronounced than that of forskolin. The total accumulation of LY was decreased by 11% in 5 min as compared to the untreated cells and this effect was persistent upon further exposition to this reagent up to 25 min. To better understand these observations, the effect of inhibitors of PKA and cAMP phosphodiesterase on fluid phase uptake was tested. 3-isobutyl-1-methyl xanthine (IBMX) caused 12% decrease in LY accumulation after 5 min of incubation. In combination with isoproterenol or forskolin, IBMX enhanced their inhibitory effect on fluid endocytosis, which was lowered by 25% and 29%, respectively. The strongest inhibitory effect on fluid endocytosis was exerted by the 10 microM PKA inhibitor, which diminished endocytosis by 35% in 5 min. These results suggest that Paramecium fluid phase uptake may be regulated through activation of PKA, although the precise mechanism of this process has not yet been elucidated.

  12. A genetic dissection of the photophobic response of Paramecium tetraurelia.

    Science.gov (United States)

    Hinrichsen, Robert; Peters, Christian

    2013-05-01

    Paramecium tetraurelia displayed two behavioral responses upon the initiation of a light stimulus at 7 x 10(4) lux. The cells exhibited a photophobic response in the form of behavioral avoiding reactions, followed by an increase in forward swimming velocity that was significantly higher than prior to the light stimulus activation. It was determined that an intensity of approximately 6.5 x 10(3) lux was required to initiate a moderate avoidance behavioral response. Following the avoiding response, a gradual increase in speed occurred as the intensity increased, indicating that increased swimming speeds are dependent on the light intensity. Two mutants, pawnA and Dancer, were utilized since they affect known Ca(2+)-currents of the cell. The use of pawnA cells, which lack voltage-dependent Ca(2+) channel activity, showed that the two responses to light could be genetically separated, in that the cells showed no avoiding reactions, but did increase their swimming speed. The Dancer cells, which display exaggerated Ca(2+) channel activity, exhibited similar initial avoiding responses as the wild type cells, however did not increase their swimming speed as the intensity of the light was increased. This phenotype as replicated in wildtype cells that had been placed in 25 μM 8-Br-cGMP. These data demonstrate that the photophobic light response of Paramecium tetraurelia can be genetically dissected as a means of elucidating the molecular mechanisms of the light response. Copyright © 2013 Elsevier GmbH. All rights reserved.

  13. Mutagenicity of fly ash samples in a test with the protozoan Paramecium tetraurelia. Onderzoek naar de mutageniteit van een aantal vliegasmonsters in een toets met het pantoffeldiertje Paramecium tetraurelia

    Energy Technology Data Exchange (ETDEWEB)

    Hooftman, R.N.

    1983-08-01

    The mutagenicity of fly ash derived from combustion of coal was investigated in a test with the protozoan Paramecium tetraurelia. This unicellular organism is able to ingest particles of the size of those that are ingested and removed by the alveolar macrophages in the lung of man and other animals: in Paramecium, as in the macrophage, ingestion is followed by intracellular extraction. Both ash from the electrostatic filter and stack-ash were mutagenic in Paramecium. The results showed similarities with and some differences from those obtained in the Ames test. There are indications that the test with Paramecium is a sensitive test for the mutagenicity of complex wastes.

  14. Mutagenicity of fly ash samples in a test with the protozoan Paramecium tetraurelia. Onderzoek naar de mutageniteit van een aantal vliegasmonsters in een toets met het pantoffeldiertje Paramecium tetraurelia

    Energy Technology Data Exchange (ETDEWEB)

    Hooftman, R.N.

    1983-08-01

    The mutagenicity of fly ash derived from combustion of coal was investigated in a test with the protozoan Paramecium tetraurelia. This unicellular organism is able to ingest particles of the size of these that are ingested and removed by the alveolar macrophages in the lung of man and other animals: in Paramecium, as in the macrophage, ingestion is followed by intracellular extraction. Both ash from the electrostatic filter and stack-ash were mutagenic in Paramecium. The results showed similarities with and some differences from those obtained in the Ames test. There are indications that the test with Paramecium is a sensitive test for the mutagenicity of complex wastes.

  15. Improved methods and resources for paramecium genomics: transcription units, gene annotation and gene expression.

    Science.gov (United States)

    Arnaiz, Olivier; Van Dijk, Erwin; Bétermier, Mireille; Lhuillier-Akakpo, Maoussi; de Vanssay, Augustin; Duharcourt, Sandra; Sallet, Erika; Gouzy, Jérôme; Sperling, Linda

    2017-06-26

    The 15 sibling species of the Paramecium aurelia cryptic species complex emerged after a whole genome duplication that occurred tens of millions of years ago. Given extensive knowledge of the genetics and epigenetics of Paramecium acquired over the last century, this species complex offers a uniquely powerful system to investigate the consequences of whole genome duplication in a unicellular eukaryote as well as the genetic and epigenetic mechanisms that drive speciation. High quality Paramecium gene models are important for research using this system. The major aim of the work reported here was to build an improved gene annotation pipeline for the Paramecium lineage. We generated oriented RNA-Seq transcriptome data across the sexual process of autogamy for the model species Paramecium tetraurelia. We determined, for the first time in a ciliate, candidate P. tetraurelia transcription start sites using an adapted Cap-Seq protocol. We developed TrUC, multi-threaded Perl software that in conjunction with TopHat mapping of RNA-Seq data to a reference genome, predicts transcription units for the annotation pipeline. We used EuGene software to combine annotation evidence. The high quality gene structural annotations obtained for P. tetraurelia were used as evidence to improve published annotations for 3 other Paramecium species. The RNA-Seq data were also used for differential gene expression analysis, providing a gene expression atlas that is more sensitive than the previously established microarray resource. We have developed a gene annotation pipeline tailored for the compact genomes and tiny introns of Paramecium species. A novel component of this pipeline, TrUC, predicts transcription units using Cap-Seq and oriented RNA-Seq data. TrUC could prove useful beyond Paramecium, especially in the case of high gene density. Accurate predictions of 3' and 5' UTR will be particularly valuable for studies of gene expression (e.g. nucleosome positioning, identification of cis

  16. Plasmodesmata of brown algae

    OpenAIRE

    Terauchi, Makoto; Nagasato, Chikako; Motomura, Taizo

    2014-01-01

    Plasmodesmata (PD) are intercellular connections in plants which play roles in various developmental processes. They are also found in brown algae, a group of eukaryotes possessing complex multicellularity, as well as green plants. Recently, we conducted an ultrastructural study of PD in several species of brown algae. PD in brown algae are commonly straight plasma membrane-lined channels with a diameter of 10?20?nm and they lack desmotubule in contrast to green plants. Moreover, branched PD ...

  17. An UPF3-based nonsense-mediated decay in Paramecium.

    Science.gov (United States)

    Contreras, Julia; Begley, Victoria; Macias, Sandra; Villalobo, Eduardo

    2014-12-01

    Nonsense-mediated decay recognises mRNAs containing premature termination codons. One of its components, UPF3, is a molecular link bridging through its binding to the exon junction complex nonsense-mediated decay and splicing. In protists UPF3 has not been identified yet. We report that Paramecium tetraurelia bears an UPF3 gene and that it has a role in nonsense-mediated decay. Interestingly, the identified UPF3 has not conserved the essential amino acids required to bind the exon junction complex. Though, our data indicates that this ciliate bears genes coding for core proteins of the exon junction complex. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  18. Sex recombination, and reproductive fitness: an experimental study using Paramecium

    Energy Technology Data Exchange (ETDEWEB)

    Nyberg, D.

    1982-08-01

    The effect of sex and recombination on reproductive fitness are measured using five wild stocks of Paramecium primaurelia. Among the wild stocks there were highly significant differences in growth rates. No hybrid had as low a fitness as the least fit parental stock. Recombination produced genotypes of higher fitness than those of either parent only in the cross between the two stocks of lowest fitness. The increase in variance of fitness as a result of recombination was almost exclusively attributable to the generation lines with low fitness. The fitness consequences of sexuality and mate choice were stock specific; some individuals leaving the most descendants by inbreeding, others by outcrossing. For most crosses the short-term advantage of sex, if any, accrue from the fusion of different gametes (hybrid vigor) and not from recombination. Since the homozygous genotype with the highest fitnes left the most progeny by inbreeding (no recombination), the persistence of conjugation in P. primaurelia is paradoxical. (JMT)

  19. [Harmful algae and health].

    Science.gov (United States)

    Kankaanpää, Harri T

    2011-01-01

    Harmful algae are a worldwide problem. Phycotoxins is a general term for toxic compounds produced by harmful species of the phytoplankton. This review deals with the occurrence of harmful algae and phycotoxins in the Baltic Sea and other domestic waters, the ways of getting exposed to them, and their effects. Advice on how to avoid the exposure is provided.

  20. Algae Derived Biofuel

    Energy Technology Data Exchange (ETDEWEB)

    Jahan, Kauser [Rowan Univ., Glassboro, NJ (United States)

    2015-03-31

    One of the most promising fuel alternatives is algae biodiesel. Algae reproduce quickly, produce oils more efficiently than crop plants, and require relatively few nutrients for growth. These nutrients can potentially be derived from inexpensive waste sources such as flue gas and wastewater, providing a mutual benefit of helping to mitigate carbon dioxide waste. Algae can also be grown on land unsuitable for agricultural purposes, eliminating competition with food sources. This project focused on cultivating select algae species under various environmental conditions to optimize oil yield. Membrane studies were also conducted to transfer carbon di-oxide more efficiently. An LCA study was also conducted to investigate the energy intensive steps in algae cultivation.

  1. Behavior of Paramecium sp. in solutions containing Sr and Pb: Do Paramecium sp. alter chemical forms of those metals?

    Science.gov (United States)

    Kozai, Naofumi; Ohnuki, Toshihiko; Koka, Masahi; Satoh, Takahiro; Kamiya, Tomihiro

    2011-10-01

    The behavior of Paramecium sp. (Paramecium bursaria) in aqueous solutions containing Sr and Pb was investigated to determine the role of protozoa in the migration of radionuclides in the environment. Precultured living cells of P. bursaria were exposed to aqueous solutions containing 0.01 or 0.05 mM Sr or Pb at pH 7 for 24 h. For comparison, pre-killed cells were treated with the metal solutions in the same way. Two-dimensional elemental mappings of cells were obtained by micro-PIXE. Aquatic species of Sr and Pb were analyzed by size exclusion chromatography (SEC) coupled online to ultraviolet (UV) spectroscopy and inductivity coupled plasma mass spectroscopy (ICP-MS). The amounts of Sr adsorbed or taken up by the cells surviving for 24 h and adsorbed on pre-killed cells were below the detection limit. Cells of P. bursaria adsorbed or took up a fraction of Pb. The Pb adsorbed or taken up by the cells surviving for 24 h in the Pb solution was barely detectable, while the Pb adsorbed on pre-killed cells was clearly mappable. These findings suggest that living cells of P. bursaria have functions that reduce adsorption or uptake of Pb on the cells. Quantitative and SEC-UV-ICP-MS analyses of the Sr and Pb in aqueous phases showed no clear evidences that living cells of P. bursaria alter the chemical form of Sr or Pb remaining in the aqueous phases after the cell-solution contact.

  2. Behavior of Paramecium sp. in solutions containing Sr and Pb: Do Paramecium sp. alter chemical forms of those metals?

    International Nuclear Information System (INIS)

    Kozai, Naofumi; Ohnuki, Toshihiko; Koka, Masahi; Satoh, Takahiro; Kamiya, Tomihiro

    2011-01-01

    The behavior of Paramecium sp. (Paramecium bursaria) in aqueous solutions containing Sr and Pb was investigated to determine the role of protozoa in the migration of radionuclides in the environment. Precultured living cells of P. bursaria were exposed to aqueous solutions containing 0.01 or 0.05 mM Sr or Pb at pH 7 for 24 h. For comparison, pre-killed cells were treated with the metal solutions in the same way. Two-dimensional elemental mappings of cells were obtained by micro-PIXE. Aquatic species of Sr and Pb were analyzed by size exclusion chromatography (SEC) coupled online to ultraviolet (UV) spectroscopy and inductivity coupled plasma mass spectroscopy (ICP-MS). The amounts of Sr adsorbed or taken up by the cells surviving for 24 h and adsorbed on pre-killed cells were below the detection limit. Cells of P. bursaria adsorbed or took up a fraction of Pb. The Pb adsorbed or taken up by the cells surviving for 24 h in the Pb solution was barely detectable, while the Pb adsorbed on pre-killed cells was clearly mappable. These findings suggest that living cells of P. bursaria have functions that reduce adsorption or uptake of Pb on the cells. Quantitative and SEC-UV-ICP-MS analyses of the Sr and Pb in aqueous phases showed no clear evidences that living cells of P. bursaria alter the chemical form of Sr or Pb remaining in the aqueous phases after the cell-solution contact.

  3. Behavior of Paramecium sp. in solutions containing Sr and Pb: Do Paramecium sp. alter chemical forms of those metals?

    Energy Technology Data Exchange (ETDEWEB)

    Kozai, Naofumi, E-mail: kozai.naofumi@jaea.go.jp [Advanced Sciences Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195 (Japan); Ohnuki, Toshihiko [Advanced Sciences Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195 (Japan); Koka, Masahi; Satoh, Takahiro; Kamiya, Tomihiro [Takasaki Advanced Radiation Research Institute, JAEA, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan)

    2011-10-15

    The behavior of Paramecium sp. (Paramecium bursaria) in aqueous solutions containing Sr and Pb was investigated to determine the role of protozoa in the migration of radionuclides in the environment. Precultured living cells of P. bursaria were exposed to aqueous solutions containing 0.01 or 0.05 mM Sr or Pb at pH 7 for 24 h. For comparison, pre-killed cells were treated with the metal solutions in the same way. Two-dimensional elemental mappings of cells were obtained by micro-PIXE. Aquatic species of Sr and Pb were analyzed by size exclusion chromatography (SEC) coupled online to ultraviolet (UV) spectroscopy and inductivity coupled plasma mass spectroscopy (ICP-MS). The amounts of Sr adsorbed or taken up by the cells surviving for 24 h and adsorbed on pre-killed cells were below the detection limit. Cells of P. bursaria adsorbed or took up a fraction of Pb. The Pb adsorbed or taken up by the cells surviving for 24 h in the Pb solution was barely detectable, while the Pb adsorbed on pre-killed cells was clearly mappable. These findings suggest that living cells of P. bursaria have functions that reduce adsorption or uptake of Pb on the cells. Quantitative and SEC-UV-ICP-MS analyses of the Sr and Pb in aqueous phases showed no clear evidences that living cells of P. bursaria alter the chemical form of Sr or Pb remaining in the aqueous phases after the cell-solution contact.

  4. Evolutionary dynamics of a conserved sequence motif in the ribosomal genes of the ciliate Paramecium

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    Lynch Michael

    2010-05-01

    Full Text Available Abstract Background In protozoa, the identification of preserved motifs by comparative genomics is often impeded by difficulties to generate reliable alignments for non-coding sequences. Moreover, the evolutionary dynamics of regulatory elements in 3' untranslated regions (both in protozoa and metazoa remains a virtually unexplored issue. Results By screening Paramecium tetraurelia's 3' untranslated regions for 8-mers that were previously found to be preserved in mammalian 3' UTRs, we detect and characterize a motif that is distinctly conserved in the ribosomal genes of this ciliate. The motif appears to be conserved across Paramecium aurelia species but is absent from the ribosomal genes of four additional non-Paramecium species surveyed, including another ciliate, Tetrahymena thermophila. Motif-free ribosomal genes retain fewer paralogs in the genome and appear to be lost more rapidly relative to motif-containing genes. Features associated with the discovered preserved motif are consistent with this 8-mer playing a role in post-transcriptional regulation. Conclusions Our observations 1 shed light on the evolution of a putative regulatory motif across large phylogenetic distances; 2 are expected to facilitate the understanding of the modulation of ribosomal genes expression in Paramecium; and 3 reveal a largely unexplored--and presumably not restricted to Paramecium--association between the presence/absence of a DNA motif and the evolutionary fate of its host genes.

  5. A new laboratory cultivation of Paramecium bursaria using non-pathogenic bacteria strains.

    Science.gov (United States)

    Bator, Tomasz

    2010-01-01

    In most studies dealing with the laboratory cultivation of paramecia (Paramecium bursaria), Klebsiella pneumoniae bacteria are used to inoculate the medium. However, Klebsiella pneumoniae is a typical pathogen, and its use is always associated with a risk of infection. The aim of the present research was to examine non-pathogenic bacteria strains as components of the medium for Paramecium bursaria. The paramecia were incubated on lettuce infusions bacterized with different bacteria strains: Bacillus subtilis DSM 10, Bacillus megaterium DSM 32, Escherichia coli DSM 498, Micrococcus luteus DSM 348. A strain derived from the natural habitat of Paramecium bursaria was used as the control one. Experiments were conducted under constant light and in the dark. Paramecia cells were counted under a stereomicroscope on consecutive days of incubation. The obtained results show that the most intensive growth of Paramecium bursaria occurs in the presence of Escherichia coli DSM 498. The use of this strain as a component of the medium allows one to obtain a high number of ciliates regardless of the light conditions. It can be concluded that the Paramecium bursaria cultivation procedure can be modified by using the non-pathogenic bacteria strain Escherichia coli DSM 498 instead of Klebsiella pneumoniae.

  6. Evolutionary dynamics of a conserved sequence motif in the ribosomal genes of the ciliate Paramecium.

    Science.gov (United States)

    Catania, Francesco; Lynch, Michael

    2010-05-04

    In protozoa, the identification of preserved motifs by comparative genomics is often impeded by difficulties to generate reliable alignments for non-coding sequences. Moreover, the evolutionary dynamics of regulatory elements in 3' untranslated regions (both in protozoa and metazoa) remains a virtually unexplored issue. By screening Paramecium tetraurelia's 3' untranslated regions for 8-mers that were previously found to be preserved in mammalian 3' UTRs, we detect and characterize a motif that is distinctly conserved in the ribosomal genes of this ciliate. The motif appears to be conserved across Paramecium aurelia species but is absent from the ribosomal genes of four additional non-Paramecium species surveyed, including another ciliate, Tetrahymena thermophila. Motif-free ribosomal genes retain fewer paralogs in the genome and appear to be lost more rapidly relative to motif-containing genes. Features associated with the discovered preserved motif are consistent with this 8-mer playing a role in post-transcriptional regulation. Our observations 1) shed light on the evolution of a putative regulatory motif across large phylogenetic distances; 2) are expected to facilitate the understanding of the modulation of ribosomal genes expression in Paramecium; and 3) reveal a largely unexplored--and presumably not restricted to Paramecium--association between the presence/absence of a DNA motif and the evolutionary fate of its host genes.

  7. Blue-Green Algae

    Science.gov (United States)

    ... people with hepatitis C or hepatitis B. HIV/AIDS. Research on the effects of blue-green algae in people with HIV/AIDS has been inconsistent. Some early research shows that taking 5 grams of blue-green ...

  8. Biofuels and algae

    International Nuclear Information System (INIS)

    Anon.

    2011-01-01

    Bio-fuels based on micro-algae are promising, their licensing for being used in plane fuels in a mix containing 50% of fossil kerosene is expected in the coming months. In United-States research on bio-fuels has been made more important since 2006 when 2 policies were launched: 'Advanced energy initiative' and 'Twenty-in-ten', the latter aiming to develop alternative fuels. In Europe less investment has been made concerning micro-algae fuels but research programs were launched in Spain, United-Kingdom and France. In France 3 important projects were launched: SHAMASH (2006-2010) whose aim is to produce lipidic fuels from micro-algae, ALGOHUB (2008-2013) whose aim is to use micro-algae as a raw material for humane and animal food, medicine and cosmetics, SYMBIOSE (2009-2011) whose aim is the optimization of the production of methane through the anaerobic digestion of micro-algae, SALINALGUE (2010-2016) whose aim is to grow micro-algae for the production of bio-energies and bio-products. (A.C.)

  9. Mechanics of membrane–cytoskeleton attachment in Paramecium

    International Nuclear Information System (INIS)

    Campillo, C; Nassoy, P; Sykes, C; Jerber, J; Fisch, C; Dupuis-Williams, P; Simoes-Betbeder, M

    2012-01-01

    In this paper we assess the role of the protein MKS1 (Meckel syndrome type 1) in the cortical membrane mechanics of the ciliated protist Paramecium. This protein is known to be crucial in the process of cilium formation, and we investigate its putative role in membrane–cytoskeleton attachment. Therefore, we compare cells where the gene coding for MKS1 is silenced to wild-type cells. We found that scanning electron microscopy observation of the cell surface reveals a cup-like structure in wild-type cells that is lost in silenced cells. Since this structure is based on the underlying cytoskeleton, one hypothesis to explain this observation is a disruption of membrane attachment to the cytoskeleton in the absence of MKS1 that should affect plasma membrane mechanics. We test this by probing the mechanics of wild-type and silenced cells by micropipette aspiration. Strikingly, we observe that, at the same aspiration pressure, the membrane of silenced cells is easily aspirated by the micropipette whereas that of wild-type cells enters only at a moderate velocity, an effect that suggests a detachment of the membrane from the underlying cytoskeleton in silenced cells. We quantify this detachment by measuring the deformation of the cell cortex and the rate of cell membrane entry in the micropipette. This study offers a new perspective for the characterization of membrane–cytoskeleton attachment in protists and paves the way for a better understanding of the role of membrane–cortex attachment in cilium formation. (paper)

  10. Ciliate Paramecium is a natural reservoir of Legionella pneumophila

    Science.gov (United States)

    Watanabe, Kenta; Nakao, Ryo; Fujishima, Masahiro; Tachibana, Masato; Shimizu, Takashi; Watarai, Masahisa

    2016-04-01

    Legionella pneumophila, the causative agent of Legionnaires’ disease, replicates within alveolar macrophages and free-living amoebae. However, the lifestyle of L. pneumophila in the environment remains largely unknown. Here we established a novel natural host model of L. pneumophila endosymbiosis using the ciliate Paramecium caudatum. We also identified Legionella endosymbiosis-modulating factor A (LefA), which contributes to the change in life stage from endosymbiosis to host lysis, enabling escape to the environment. We isolated L. pneumophila strains from the environment, and they exhibited cytotoxicity toward P. caudatum and induced host lysis. Acidification of the Legionella-containing vacuole (LCV) was inhibited, and enlarged LCVs including numerous bacteria were observed in P. caudatum infected with L. pneumophila. An isogenic L. pneumophila lefA mutant exhibited decreased cytotoxicity toward P. caudatum and impaired the modification of LCVs, resulting in the establishment of endosymbiosis between them. Our results suggest that L. pneumophila may have a mechanism to switch their endosymbiosis in protistan hosts in the environment.

  11. Alteration of Paramecium candatum germinal nucleus morphology after UV irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fokin, S.I. (Leningradskij Gosudarstvennyj Univ. (USSR). Biologicheskij Nauchno-Issledovatel' skij Inst.)

    1982-09-01

    A study was made on morphologic changes of micronucleus (Mi) after whole-body ultraviolet (UV) irradiation of paramecia as well as after local irradiation of this nucleus or the area of macronucleus (Ma). The whole-body irradiation of its Ma part leads to generative nucleus growth in sizes and chromatin structure change, which is expressed in occurence of large chromatin bodies. Aftereffects of local action on Mi for viable descendants are expressed in nucleus size transformation (usually in reduction), gaining ''comet-shaped'' form and probably in reduction of dna amount. Irradiation of Ma and total effect on cell cause Mi changes of reversible character. All morphologic changes of Mi after local ultraviolet irradiation are conserved in descendants and are not photoreactivated. Possible reasons for this phenomenon are discussed. The results obtained make it possible to speak about different mechanisms of action on Mi in the case of local and whole-body UV irradiation of cell. The effect of irradiated Ma on generative nucleus, but not direct damage of this nucleus is the reason for Mi morphologic reconstruction after whole-body action on paramecium.

  12. Proliferation kinetics of paramecium tetraurelia in balloon-borne experiments

    International Nuclear Information System (INIS)

    Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Rousseille, R.; Planel, H.

    1982-01-01

    Experiments were carried out to demonstrate the effect of cosmic radiation, at a balloon-flight ceiling of about 36,500 m (120,000 ft) on single-cell organism proliferation. Paramecium tetraurelia were placed in air-tight containers and maintained at 25 degrees +/- 0.1 degrees C. Cellular growth was determined by cell count, either after recovery or during the flight, by means of an automatic fixation device. Dosimetry was performed by a tissue equivalent proportional counter and was of about 0.5 mrad/h. Flight ceiling duration ranged from 48 min - 22 h. A secondary stimulating effect of growth rate, preceded by a temporary decrease, was observed after recovery. Because of the high bacterial concentration in the trans-Mediterranean flight culture medium, the temporary drop of the growth rate, due to the radiolysis products, disappears. Researchers consider that the stimulating effect can be the result of enzymatic intracellular scavenging of radiolysis products generated in the cell

  13. Mechanics of membrane-cytoskeleton attachment in Paramecium

    Science.gov (United States)

    Campillo, C.; Jerber, J.; Fisch, C.; Simoes-Betbeder, M.; Dupuis-Williams, P.; Nassoy, P.; Sykes, C.

    2012-12-01

    In this paper we assess the role of the protein MKS1 (Meckel syndrome type 1) in the cortical membrane mechanics of the ciliated protist Paramecium. This protein is known to be crucial in the process of cilium formation, and we investigate its putative role in membrane-cytoskeleton attachment. Therefore, we compare cells where the gene coding for MKS1 is silenced to wild-type cells. We found that scanning electron microscopy observation of the cell surface reveals a cup-like structure in wild-type cells that is lost in silenced cells. Since this structure is based on the underlying cytoskeleton, one hypothesis to explain this observation is a disruption of membrane attachment to the cytoskeleton in the absence of MKS1 that should affect plasma membrane mechanics. We test this by probing the mechanics of wild-type and silenced cells by micropipette aspiration. Strikingly, we observe that, at the same aspiration pressure, the membrane of silenced cells is easily aspirated by the micropipette whereas that of wild-type cells enters only at a moderate velocity, an effect that suggests a detachment of the membrane from the underlying cytoskeleton in silenced cells. We quantify this detachment by measuring the deformation of the cell cortex and the rate of cell membrane entry in the micropipette. This study offers a new perspective for the characterization of membrane-cytoskeleton attachment in protists and paves the way for a better understanding of the role of membrane-cortex attachment in cilium formation.

  14. Anticoagulant effect of marine algae.

    Science.gov (United States)

    Kim, Se-Kwon; Wijesekara, Isuru

    2011-01-01

    Recently, a great deal of interest has been developed in the nutraceutical and pharmaceutical industries to isolate natural anticoagulant compounds from marine resources. Among marine resources, marine algae are valuable sources of novel bioactive compounds with anticoagulant effect. Phlorotannins and sulfated polysaccharides such as fucoidans in brown algae, carrageenans in red algae, and ulvans in green algae have been recognized as potential anticoagulant agents. Therefore, marine algae-derived phlorotannins and SPs have great potential for developing as anticoagulant drugs in nutraceutical and pharmaceutical areas. This chapter focuses on the potential anticoagulant agents in marine algae and presents an overview of their anticoagulant effect. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Plasmodesmata of brown algae.

    Science.gov (United States)

    Terauchi, Makoto; Nagasato, Chikako; Motomura, Taizo

    2015-01-01

    Plasmodesmata (PD) are intercellular connections in plants which play roles in various developmental processes. They are also found in brown algae, a group of eukaryotes possessing complex multicellularity, as well as green plants. Recently, we conducted an ultrastructural study of PD in several species of brown algae. PD in brown algae are commonly straight plasma membrane-lined channels with a diameter of 10-20 nm and they lack desmotubule in contrast to green plants. Moreover, branched PD could not be observed in brown algae. In the brown alga, Dictyota dichotoma, PD are produced during cytokinesis through the formation of their precursor structures (pre-plasmodesmata, PPD). Clustering of PD in a structure termed "pit field" was recognized in several species having a complex multicellular thallus structure but not in those having uniseriate filamentous or multiseriate one. The pit fields might control cell-to-cell communication and contribute to the establishment of the complex multicellular thallus. In this review, we discuss fundamental morphological aspects of brown algal PD and present questions that remain open.

  16. Pdsg1 and Pdsg2, novel proteins involved in developmental genome remodelling in Paramecium.

    Directory of Open Access Journals (Sweden)

    Miroslav Arambasic

    Full Text Available The epigenetic influence of maternal cells on the development of their progeny has long been studied in various eukaryotes. Multicellular organisms usually provide their zygotes not only with nutrients but also with functional elements required for proper development, such as coding and non-coding RNAs. These maternally deposited RNAs exhibit a variety of functions, from regulating gene expression to assuring genome integrity. In ciliates, such as Paramecium these RNAs participate in the programming of large-scale genome reorganization during development, distinguishing germline-limited DNA, which is excised, from somatic-destined DNA. Only a handful of proteins playing roles in this process have been identified so far, including typical RNAi-derived factors such as Dicer-like and Piwi proteins. Here we report and characterize two novel proteins, Pdsg1 and Pdsg2 (Paramecium protein involved in Development of the Somatic Genome 1 and 2, involved in Paramecium genome reorganization. We show that these proteins are necessary for the excision of germline-limited DNA during development and the survival of sexual progeny. Knockdown of PDSG1 and PDSG2 genes affects the populations of small RNAs known to be involved in the programming of DNA elimination (scanRNAs and iesRNAs and chromatin modification patterns during development. Our results suggest an association between RNA-mediated trans-generational epigenetic signal and chromatin modifications in the process of Paramecium genome reorganization.

  17. The Use of Paramecium to Observe the Toxic Effect of Cigarette Smoke.

    Science.gov (United States)

    Bardell, David

    1986-01-01

    Describes a laboratory experiment in which Paramecium caudatum was used to demonstrate the toxic effect of cigarette smoke on the cilia of epithelium cells lining the trachea and bronchi of smokers. Provides background information and explains the procedure, including how to make a simple mechanical smoking device. (TW)

  18. Pdsg1 and Pdsg2, novel proteins involved in developmental genome remodelling in Paramecium.

    Science.gov (United States)

    Arambasic, Miroslav; Sandoval, Pamela Y; Hoehener, Cristina; Singh, Aditi; Swart, Estienne C; Nowacki, Mariusz

    2014-01-01

    The epigenetic influence of maternal cells on the development of their progeny has long been studied in various eukaryotes. Multicellular organisms usually provide their zygotes not only with nutrients but also with functional elements required for proper development, such as coding and non-coding RNAs. These maternally deposited RNAs exhibit a variety of functions, from regulating gene expression to assuring genome integrity. In ciliates, such as Paramecium these RNAs participate in the programming of large-scale genome reorganization during development, distinguishing germline-limited DNA, which is excised, from somatic-destined DNA. Only a handful of proteins playing roles in this process have been identified so far, including typical RNAi-derived factors such as Dicer-like and Piwi proteins. Here we report and characterize two novel proteins, Pdsg1 and Pdsg2 (Paramecium protein involved in Development of the Somatic Genome 1 and 2), involved in Paramecium genome reorganization. We show that these proteins are necessary for the excision of germline-limited DNA during development and the survival of sexual progeny. Knockdown of PDSG1 and PDSG2 genes affects the populations of small RNAs known to be involved in the programming of DNA elimination (scanRNAs and iesRNAs) and chromatin modification patterns during development. Our results suggest an association between RNA-mediated trans-generational epigenetic signal and chromatin modifications in the process of Paramecium genome reorganization.

  19. IDENTIFICATION OF PARAMECIUM BURSARIA SYNGENS THROUGH MOLECULAR MARKERS – COMPARATIVE ANALYSIS OF MITOCHONDRIAL CYTOCHROME C OXIDASE SUBUNIT I (COI

    Directory of Open Access Journals (Sweden)

    Patrycja Zagata

    2014-08-01

    Full Text Available The aim of this study is an identification of Paramecium bursaria syngens originating from different geographical locations and proving the correlation between distributions and belonging to any of five syngens. Ten strains of Paramecium bursaria belonging to five different syngens and strain of Paramecium multimicronucleatum were investigated using molecular marker — mitochondrial cytochrome c oxidase subunit I (COI. According to results, obtained in this study, using phylogenetic methods like Neighbor Joining (NJ and Maximum Likelihood (ML, relationship between analyzing strains through their clustering in clusters and correlation between strains belonging to any syngen and syngen’s distribution was confirmed. Phylograms constructed using NJ and ML methods revealed strains’ grouping in five clusters. Results which were obtained revealed usefulness of COI as a biomarker, which is important in identification of Paramecium bursaria syngens. This reports to a great potential of COI as a molecular marker and obtaining dependable results through combination of molecular methods with classical ones.

  20. Phagosome maturation in unicellular eukaryote Paramecium: the presence of RILP, Rab7 and LAMP-2 homologues.

    Science.gov (United States)

    Wyroba, E; Surmacz, L; Osinska, M; Wiejak, J

    2007-01-01

    Phagosome maturation is a complex process enabling degradation of internalised particles. Our data obtained at the gene, protein and cellular level indicate that the set of components involved in this process and known up to now in mammalian cells is functioning in unicellular eukaryote. Rab7-interacting partners: homologues of its effector RILP (Rab-interacting lysosomal protein) and LAMP-2 (lysosomal membrane protein 2) as well as alpha7 subunit of the 26S proteasome were revealed in Paramecium phagolysosomal compartment. We identified the gene/transcript fragments encoding RILP-related proteins (RILP1 and RILP2) in Paramecium by PCR/RT-PCR and sequencing. The deduced amino acid sequences of RILP1 and RILP2 show 60.5% and 58.3% similarity, respectively, to the region involved in regulating of lysosomal morphology and dynein-dynactin recruitment of human RILP. RILP colocalised with Rab7 in Paramecium lysosomes and at phagolysosomal membrane during phagocytosis of both the latex beads and bacteria. In the same compartment LAMP-2 was present and its expression during latex internalisation was 2.5-fold higher than in the control when P2 protein fractions (100,000 x g) of equal load were quantified by immunoblotting. LAMP-2 cross-reacting polypeptide of approximately106 kDa was glycosylated as shown by fluorescent and Western analysis of the same blot preceded by PNGase F treatment. The alpha7 subunit of 26S proteasome was detected close to the phagosomal membrane in the small vesicles, in some of which it colocalised with Rab7. Immunoblotting confirmed presence of RILP-related polypeptide and a7 subunit of 26S proteasome in Paramecium protein fractions. These results suggest that Rab7, RILP and LAMP-2 may be involved in phagosome maturation in Paramecium.

  1. Phagosome maturation in unicellular eukaryote Paramecium: the presence of RILP, Rab7 and LAMP-2 homologues

    Directory of Open Access Journals (Sweden)

    E Wyroba

    2009-08-01

    Full Text Available Phagosome maturation is a complex process enabling degradation of internalised particles. Our data obtained at the gene, protein and cellular level indicate that the set of components involved in this process and known up to now in mammalian cells is functioning in unicellular eukaryote. Rab7-interacting partners: homologues of its effector RILP (Rab-interacting lysosomal protein and LAMP-2 (lysosomal membrane protein 2 as well as a7 subunit of the 26S proteasome were revealed in Paramecium phagolysosomal compartment. We identified the gene/transcript fragments encoding RILP-related proteins (RILP1 and RILP2 in Paramecium by PCR/RT-PCR and sequencing. The deduced amino acid sequences of RILP1 and RILP2 show 60.5% and 58.3% similarity, respectively, to the region involved in regulating of lysosomal morphology and dynein-dynactin recruitment of human RILP. RILP colocalised with Rab7 in Paramecium lysosomes and at phagolysosomal membrane during phagocytosis of both the latex beads and bacteria. In the same compartment LAMP-2 was present and its expression during latex internalisation was 2.5-fold higher than in the control when P2 protein fractions (100 000 x g of equal load were quantified by immunoblotting. LAMP-2 crossreacting polypeptide of ~106 kDa was glycosylated as shown by fluorescent and Western analysis of the same blot preceded by PNGase F treatment. The a7 subunit of 26S proteasome was detected close to the phagosomal membrane in the small vesicles, in some of which it colocalised with Rab7. Immunoblotting confirmed presence of RILPrelated polypeptide and a7 subunit of 26S proteasome in Paramecium protein fractions. These results suggest that Rab7, RILP and LAMP-2 may be involved in phagosome maturation in Paramecium.

  2. Variability in secondary structure of 18S ribosomal RNA as topological marker for identification of Paramecium species.

    Science.gov (United States)

    Shakoori, Farah R; Tasneem, Fareeda; Al-Ghanim, K; Mahboob, S; Al-Misned, F; Jahan, Nusrat; Shakoori, Abdul Rauf

    2014-12-01

    Besides cytological and molecular applications, Paramecium is being used in water quality assessment and for determination of saprobic levels. An unambiguous identification of these unicellular eukaryotes is not only essential, but its ecological diversity must also be explored in the local environment. 18SrRNA genes of all the strains of Paramecium species isolated from waste water were amplified, cloned and sequenced. Phylogenetic comparison of the nucleotide sequences of these strains with 23 closely related Paramecium species from GenBank Database enabled identification of Paramecium multimicronucleatum and Paramecium jenningsi. Some isolates did not show significant close association with other Paramecium species, and because of their unique position in the phylogenetic tree, they were considered new to the field. In the present report, these isolates are being designated as Paramecium caudatum pakistanicus. In this article, secondary structure of 18SrRNA has also been analyzed as an additional and perhaps more reliable topological marker for species discrimination and for determining possible phylogenetic relationship between the ciliate species. On the basis of comparison of secondary structure of 18SrRNA of various isolated Paramacium strains, and among Paramecium caudatum pakistanicus, Tetrahymena thermophila, Drosophila melanogaster, and Homo sapiens, it can be deduced that variable regions are more helpful in differentiating the species at interspecific level rather than at intraspecific level. It was concluded that V3 was the least variable region in all the organisms, V2 and V7 were the longest expansion segments of D. melanogaster and there was continuous mutational bias towards G.C base pairing in H. sapiens. © 2014 Wiley Periodicals, Inc.

  3. Identification of Paramecium bursaria syngens through molecular markers--comparative analysis of three loci in the nuclear and mitochondrial DNA.

    Science.gov (United States)

    Greczek-Stachura, Magdalena; Potekhin, Alexey; Przyboś, Ewa; Rautian, Maria; Skoblo, Inna; Tarcz, Sebastian

    2012-09-01

    This is the first attempt to resolve the phylogenetic relationship between different syngens of Paramecium bursaria and to investigate at a molecular level the intraspecific differentiation of strains originating from very distant geographical locations. Herein we introduce a new collection of five P. bursaria syngens maintained at St Petersburg State University, as the international collection of syngens was lost in the 1960s. To analyze the degree of speciation within Paramecium bursaria, we examined 26 strains belonging to five different syngens from distant and geographically isolated localities using rDNA (ITS1-5.8S-ITS2-5'LSU) fragments, mitochondrial cytochrome c oxidase subunit I (COI), and H4 gene fragments. It was shown that P. bursaria strains of the same syngens cluster together in all three inferred molecular phylogenies. The genetic diversity among the studied P. bursaria strains based on rDNA sequences was rather low. The COI divergence of Paramecium bursaria was also definitely lower than that observed in the Paramecium aurelia complex. The nucleotide sequences of the H4 gene analyzed in the present study indicate the extent of genetic differences between the syngens of Paramecium bursaria. Our study demonstrates the diagnostic value of molecular markers, which are important tools in the identification of Paramecium bursaria syngens. Copyright © 2011 Elsevier GmbH. All rights reserved.

  4. "Candidatus Sonnebornia yantaiensis", a member of candidate division OD1, as intracellular bacteria of the ciliated protist Paramecium bursaria (Ciliophora, Oligohymenophorea).

    Science.gov (United States)

    Gong, Jun; Qing, Yao; Guo, Xiaohong; Warren, Alan

    2014-02-01

    An intracellular bacterium was discovered in an isolate of Paramecium bursaria from a freshwater pond in Yantai, China. The bacteria were abundant and exclusively found in the cytoplasm of the host which, along with the green alga Chlorella, formed a three-partner consortium that could survive in pure water for at least one week. Cloning, sequencing and phylogenetic analysis of the bacterial 16S rRNA gene showed that the bacterium belonged to the uncultured candidate division OD1, which usually forms part of the rare biosphere. Transmission electron microscopy and fluorescence in situ hybridization (FISH) with specific probes showed that the bacteria were usually located close to the perialgal membranes of endosymbiotic Chlorella cells, and occasionally irregularly distributed throughout the host cytoplasm. The name "Candidatus Sonnebornia yantaiensis" gen. nov., sp. nov. is proposed for the new bacterium. A strongly supported monophyletic subclade, OD1-p, which included the new species, was recognized and this study highlights that protists can be important hosts for rare bacterial taxa. Copyright © 2013 Elsevier GmbH. All rights reserved.

  5. Genomics of Volvocine Algae

    Science.gov (United States)

    Umen, James G.; Olson, Bradley J.S.C.

    2015-01-01

    Volvocine algae are a group of chlorophytes that together comprise a unique model for evolutionary and developmental biology. The species Chlamydomonas reinhardtii and Volvox carteri represent extremes in morphological diversity within the Volvocine clade. Chlamydomonas is unicellular and reflects the ancestral state of the group, while Volvox is multicellular and has evolved numerous innovations including germ-soma differentiation, sexual dimorphism, and complex morphogenetic patterning. The Chlamydomonas genome sequence has shed light on several areas of eukaryotic cell biology, metabolism and evolution, while the Volvox genome sequence has enabled a comparison with Chlamydomonas that reveals some of the underlying changes that enabled its transition to multicellularity, but also underscores the subtlety of this transition. Many of the tools and resources are in place to further develop Volvocine algae as a model for evolutionary genomics. PMID:25883411

  6. Transcriptomics in brown algae

    OpenAIRE

    Heinrich, Sandra

    2015-01-01

    Brown algae are distributed worldwide on rocky shores. They are importenet components of ecosystems, they provide habitat, shelter and serve as nurseries for various marine organisms. The geographic as well as depth distribution of macroalgae is constrained by abiotic factors, especially light and temperature. It is therefore likely that due to the global change, distribution patterns of these organisms will change. In this work the molecular acclimation of two prominent brown macroalgae, Sac...

  7. Factors Determining the Frequency of the Killer Trait within Populations of the Paramecium aurelia Complex

    Science.gov (United States)

    Landis, Wayne G.

    1987-01-01

    The factors maintaining the cytoplasmically inherited killer trait in populations of Paramecium tetraurelia and Paramecium biaurelia were examined using, in part, computer simulation. Frequency of the K and k alleles, infection and loss of the endosymbionts, recombination during conjugation and autogamy, cytoplasmic exchange and natural selection were incorporated in a model. Infection during cytoplasmic exchange at conjugation and natural selection were factors that would increase the proportion of killers in a population. Conversely, k alleles reduced the proportion of killers in a population, acting through conjugation and autogamy. Field studies indicate that the odd mating type is prevalent in P. tetraurelia isolated from nature. Conjugation and therefore transmission by cytoplasmic transfer would be rare. Competition studies indicate a strong selective disadvantage for sensitives at concentrations found in nature. Natural selection must therefore be the factor maintaining the killer trait in P. tetraurelia. PMID:3557112

  8. Using Magnetic Forces to Probe the Gravi-response of Swimming Paramecium

    Science.gov (United States)

    Guevorkian, Karine; Valles, James M., Jr.

    2004-03-01

    Paramecium Caudatum, a single celled ciliate, alters its swimming behavior when subjected to different gravity environments (e.g. centrifugation and micro-gravity). To dissect the mechanisms behind this gravi-response and that of other biological systems, we are developing the use of magnetic body forces as a means of creating a rapidly tunable, simulated variable gravity environment. Since biological materials are weakly diamagnetic, we must subject them to intense inhomogeneous magnetic fields with characteristic field-field gradient products on the order of 16 T^2/cm. We will describe experiments on Paramecium Caudatum in which we adjust their net buoyancy with magnetic forces and measure the resulting changes in their swimming behavior.

  9. Genetic differentiation of the mitochondrial cytochrome oxidase C subunit I gene in genus Paramecium (Protista, Ciliophora.

    Directory of Open Access Journals (Sweden)

    Yan Zhao

    Full Text Available BACKGROUND: The mitochondrial cytochrome c oxidase subunit I (COI gene is being used increasingly for evaluating inter- and intra-specific genetic diversity of ciliated protists. However, very few studies focus on assessing genetic divergence of the COI gene within individuals and how its presence might affect species identification and population structure analyses. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated the genetic variation of the COI gene in five Paramecium species for a total of 147 clones derived from 21 individuals and 7 populations. We identified a total of 90 haplotypes with several individuals carrying more than one haplotype. Parsimony network and phylogenetic tree analyses revealed that intra-individual diversity had no effect in species identification and only a minor effect on population structure. CONCLUSIONS: Our results suggest that the COI gene is a suitable marker for resolving inter- and intra-specific relationships of Paramecium spp.

  10. Paramecium species ingest and kill the cells of the human pathogenic fungus Cryptococcus neoformans.

    Science.gov (United States)

    Frager, Shalom Z; Chrisman, Cara J; Shakked, Rachel; Casadevall, Arturo

    2010-08-01

    A fundamental question in the field of medical mycology is the origin of virulence in those fungal pathogens acquired directly from the environment. In recent years, it was proposed that the virulence of certain environmental animal-pathogenic microbes, such as Cryptococcus neoformans, originated from selection pressures caused by species-specific predation. In this study, we analyzed the interaction of C. neoformans with three Paramecium spp., all of which are ciliated mobile protists. In contrast to the interaction with amoebae, some Paramecium spp. rapidly ingested C. neoformans and killed the fungus. This study establishes yet another type of protist-fungal interaction supporting the notion that animal-pathogenic fungi in the environment are under constant selection by predation.

  11. Genetic differentiation of the mitochondrial cytochrome oxidase C subunit I gene in genus Paramecium (Protista, Ciliophora).

    Science.gov (United States)

    Zhao, Yan; Gentekaki, Eleni; Yi, Zhenzhen; Lin, Xiaofeng

    2013-01-01

    The mitochondrial cytochrome c oxidase subunit I (COI) gene is being used increasingly for evaluating inter- and intra-specific genetic diversity of ciliated protists. However, very few studies focus on assessing genetic divergence of the COI gene within individuals and how its presence might affect species identification and population structure analyses. We evaluated the genetic variation of the COI gene in five Paramecium species for a total of 147 clones derived from 21 individuals and 7 populations. We identified a total of 90 haplotypes with several individuals carrying more than one haplotype. Parsimony network and phylogenetic tree analyses revealed that intra-individual diversity had no effect in species identification and only a minor effect on population structure. Our results suggest that the COI gene is a suitable marker for resolving inter- and intra-specific relationships of Paramecium spp.

  12. ParTIES: a toolbox for Paramecium interspersed DNA elimination studies.

    Science.gov (United States)

    Denby Wilkes, Cyril; Arnaiz, Olivier; Sperling, Linda

    2016-02-15

    Developmental DNA elimination occurs in a wide variety of multicellular organisms, but ciliates are the only single-celled eukaryotes in which this phenomenon has been reported. Despite considerable interest in ciliates as models for DNA elimination, no standard methods for identification and characterization of the eliminated sequences are currently available. We present the Paramecium Toolbox for Interspersed DNA Elimination Studies (ParTIES), designed for Paramecium species, that (i) identifies eliminated sequences, (ii) measures their presence in a sequencing sample and (iii) detects rare elimination polymorphisms. ParTIES is multi-threaded Perl software available at https://github.com/oarnaiz/ParTIES. ParTIES is distributed under the GNU General Public Licence v3. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  13. The mitochondrial genome sequence of the ciliate Paramecium caudatum reveals a shift in nucleotide composition and codon usage within the genus Paramecium

    Directory of Open Access Journals (Sweden)

    Berendonk Thomas U

    2011-05-01

    Full Text Available Abstract Background Despite the fact that the organization of the ciliate mitochondrial genome is exceptional, only few ciliate mitochondrial genomes have been sequenced until today. All ciliate mitochondrial genomes are linear. They are 40 kb to 47 kb long and contain some 50 tightly packed genes without introns. Earlier studies documented that the mitochondrial guanine + cytosine contents are very different between Paramecium tetraurelia and all studied Tetrahymena species. This raises the question of whether the high mitochondrial G+C content observed in P. tetraurelia is a characteristic property of Paramecium mtDNA, or whether it is an exception of the ciliate mitochondrial genomes known so far. To test this question, we determined the mitochondrial genome sequence of Paramecium caudatum and compared the gene content and sequence properties to the closely related P. tetraurelia. Results The guanine + cytosine content of the P. caudatum mitochondrial genome was significantly lower than that of P. tetraurelia (22.4% vs. 41.2%. This difference in the mitochondrial nucleotide composition was accompanied by significantly different codon usage patterns in both species, i.e. within P. caudatum clearly A/T ending codons dominated, whereas for P. tetraurelia the synonymous codons were more balanced with a higher number of G/C ending codons. Further analyses indicated that the nucleotide composition of most members of the genus Paramecium resembles that of P. caudatum and that the shift observed in P. tetraurelia is restricted to the P. aurelia species complex. Conclusions Surprisingly, the codon usage bias in the P. caudatum mitochondrial genome, exemplified by the effective number of codons, is more similar to the distantly related T. pyriformis and other single-celled eukaryotes such as Chlamydomonas, than to the closely related P. tetraurelia. These differences in base composition and codon usage bias were, however, not reflected in the amino

  14. Effects of autogamy in Paramecium tetraurelia on catalase activity and on radiosensitivity to natural ionizing radiations

    International Nuclear Information System (INIS)

    Croute, F.; Dupouy, D.; Charley, J.P.; Soleilhavoup, J.P.; Planel, H.

    1980-01-01

    Catalase activity of Paramecium tetraurelia decreased during autogamy and recovered to normal 5 days later. Autogamy also caused changes in the ciliate's sensitivity sensitivity to natural ionizing radiations - the decrease in cell growth rate previously described in shielded cultures did not occur when autogamous cells were used. Maximum effect of shielding was observed in 11-day-old postautogamous cells. The role of the catalase in the mechanism of natural irradiation effect is discussed

  15. Water quality bioassay using selected protozoa. I. [Paramecium candatum; Amoeba proteus; Euglena gracilis

    Energy Technology Data Exchange (ETDEWEB)

    Mills, W.L.

    1976-01-01

    The suitability of certain species of protozoa as indicators of water quality has been determined. Experiments were conducted under laboratory conditions to standardize a bioassay procedure for water quality using either Paramecium caudatum, Amoeba proteus, or Euglena gracilis as the indicator organism. The bioassay, which consists of exposing the organisms to a known concentration of pollutant under laboratory conditions, followed by microscopic observation to establish the time of death, affords a reliable, convenient and inexpensive way to monitor for water quality.

  16. Optical Manipulation of Symbiotic Chlorella in Paramecium Bursaria Using a Fiber Axicon Microlens

    International Nuclear Information System (INIS)

    Taguchi, K; Hirota, S; Nakayama, H; Kunugihara, D; Mihara, Y

    2012-01-01

    In this paper, chemically etched axicon fiber was proposed for laser trapping of symbiotic chlorella from paramecium bursaria. We fabricated axicon micro lenses on a single-mode bare optical fiber by selective chemical etching technique. The laser beam from fiber axicon microlens was strongly focused and optical forces were sufficient to move a symbiotic chlorella. From experimental results, it was found that our proposed fiber axicon microlens was a promising tool for cell trapping without physical contact.

  17. Optical Manipulation of Symbiotic Chlorella in Paramecium Bursaria Using a Fiber Axicon Microlens

    Science.gov (United States)

    Taguchi, K.; Hirota, S.; Nakayama, H.; Kunugihara, D.; Mihara, Y.

    2012-03-01

    In this paper, chemically etched axicon fiber was proposed for laser trapping of symbiotic chlorella from paramecium bursaria. We fabricated axicon micro lenses on a single-mode bare optical fiber by selective chemical etching technique. The laser beam from fiber axicon microlens was strongly focused and optical forces were sufficient to move a symbiotic chlorella. From experimental results, it was found that our proposed fiber axicon microlens was a promising tool for cell trapping without physical contact.

  18. Comparative study of proliferation kinetics of paramecium tetraurelia aboard a satellite and a balloon flight

    International Nuclear Information System (INIS)

    Tixador, Rene; Richoilley, Gerard; Gasset, Gilbert; Planel, Hubert

    1982-01-01

    A possible effect of cosmic rays on cell proliferation was investigated in cultures of Paramecium tetraurelia during a stratospheric balloon flight, with the techniques already used for the CYTOS experiments, performed aboard the orbital station Salyut 6. The results show that the stimulating effect of space on cell proliferation, reported in the CYTOS experiments, also occurs in the balloon flight. The respective roles of cosmic rays and weightlesness in the biological responses are discussed [fr

  19. Gene expression in a paleopolyploid: a transcriptome resource for the ciliate Paramecium tetraurelia

    Directory of Open Access Journals (Sweden)

    Kapusta Aurélie

    2010-10-01

    Full Text Available Abstract Background The genome of Paramecium tetraurelia, a unicellular model that belongs to the ciliate phylum, has been shaped by at least 3 successive whole genome duplications (WGD. These dramatic events, which have also been documented in plants, animals and fungi, are resolved over evolutionary time by the loss of one duplicate for the majority of genes. Thanks to a low rate of large scale genome rearrangement in Paramecium, an unprecedented large number of gene duplicates of different ages have been identified, making this organism an outstanding model to investigate the evolutionary consequences of polyploidization. The most recent WGD, with 51% of pre-duplication genes still in 2 copies, provides a snapshot of a phase of rapid gene loss that is not accessible in more ancient polyploids such as yeast. Results We designed a custom oligonucleotide microarray platform for P. tetraurelia genome-wide expression profiling and used the platform to measure gene expression during 1 the sexual cycle of autogamy, 2 growth of new cilia in response to deciliation and 3 biogenesis of secretory granules after massive exocytosis. Genes that are differentially expressed during these time course experiments have expression patterns consistent with a very low rate of subfunctionalization (partition of ancestral functions between duplicated genes in particular since the most recent polyploidization event. Conclusions A public transcriptome resource is now available for Paramecium tetraurelia. The resource has been integrated into the ParameciumDB model organism database, providing searchable access to the data. The microarray platform, freely available through NimbleGen Systems, provides a robust, cost-effective approach for genome-wide expression profiling in P. tetraurelia. The expression data support previous studies showing that at short evolutionary times after a whole genome duplication, gene dosage balance constraints and not functional change are

  20. Synthesis of chiral phosphonoacetamides and their toxic effects on paramecium sp

    Directory of Open Access Journals (Sweden)

    Samia Guezane Lakoud

    2015-02-01

    Full Text Available Three chiral phosphonoacetamides were prepared by an alternative method . For this purpose, 2-(diethoxyphosphorylacetic acid was prepared from ethyl 2-bromoacetate by treatment of P(OEt 3 followed by saponification of the ester with K 2CO 3. BOP activated amidation of the 2-(diethoxyphosphorylacetic acid with (S-amino acids gave the corresponding phosphonoaceteamides. Growth inhibition of two phosphonoacetamides on Paramecium sp. were studied.

  1. Passage of selected heavy metals from Sphaerotilus (bacteria: Chlamydobacteriales) to Paramecium caudatum (protozoa: Ciliata)

    Energy Technology Data Exchange (ETDEWEB)

    Mansouri-Aliabadi, M.; Sharp, R.E.

    1985-01-01

    Sphaerotilus, a bacterium occurring in polluted waters, was found to take up Zn, Pb, Ni and Mn. Metal-containing cultures of this bacterium were employed to feed the protozoan Paramecium caudatum, and analytical results revealed the accumulation of Zn, Pb and Ni. Since Sphaerotilus wa the only food source for paramecia during this study, the results indicate that trace amounts of metal were passed from bacteria to protozoa in a predator-prey relationship.

  2. Phenotypic and Genetic Analysis of ``chameleon,'' a Paramecium Mutant with an Enhanced Sensitivity to Magnesium

    OpenAIRE

    Preston, R. R.; Hammond, J. A.

    1997-01-01

    Three mutant strains of Paramecium tetraurelia with an enhanced sensitivity to magnesium have been isolated. These new ``Chameleon'' mutants result from partial- or codominant mutations at a single locus, Cha. Whereas the wild type responded to 5 mM Mg(2+) by swimming backward for 10-15 sec, Cha mutants responded with ~30 sec backward swimming. Electrophysiological analysis suggested that this behavior may be caused by slowing in the rate at which a Mg(2+)-specific ion conductance deactivates...

  3. Identification of an algal carbon fixation-enhancing factor extracted from Paramecium bursaria.

    Science.gov (United States)

    Kato, Yutaka; Imamura, Nobutaka

    2011-01-01

    The green ciliate Paramecium bursaria contains several hundred symbiotic Chlorella species. We previously reported that symbiotic algal carbon fixation is enhanced by P. bursaria extracts and that the enhancing factor is a heat-stable, low-molecular-weight, water-soluble compound. To identify the factor, further experiments were carried out. The enhancing activity remained even when organic compounds in the extract were completely combusted at 700 degrees C, suggesting that the factor is an inorganic substance. Measurement of the major cations, K+, Ca2+, and Mg2+, by an electrode and titration of the extract resulted in concentrations of 0.90 mM, 0.55 mM, and 0.21 mM, respectively. To evaluate the effect of these cations, a mixture of the cations at the measured concentrations was prepared, and symbiotic algal carbon fixation was measured in the solution. The results demonstrated that the fixation was enhanced to the same extent as with the P. bursaria extract, and thus this mixture of K+, Ca2+, and Mg2+ was concluded to be the carbon fixation-enhancing factor. There was no effect of the cation mixture on free-living C. vulgaris. Comparison of the cation concentrations of nonsymbiotic and symbiotic Paramecium extracts revealed that the concentrations of K+ and Mg2+ in nonsymbiotic Paramecium extracts were too low to enhance symbiotic algal carbon fixation, suggesting that symbiotic P. bursaria provide suitable cation conditions for photosynthesis to its symbiotic Chlorella.

  4. Jump if you can't take the heat: three escape gaits of Paramecium swimming

    Science.gov (United States)

    Baroud, Charles N.; Hamel, Amandine; Fisch, Cathy; Combettes, Laurent; Dupuys-Williams, Pascale

    2010-11-01

    Paramecium is able to swim at velocities reaching several times its body size per second, by beating its thousands of cilia in an organized fashion. Here we show that Paramecium has in fact three distinct swimming gaits to escape from an aggression in the form of localized heating, depending on the magnitude of the aggression: For a weak agression, normal swimming is sufficient and produces a steady swimming velocity through cilia beating. As the heating amplitude is increased, a higher acceleration and faster swimming are achieved through synchronized beating of the cilia, which later give way to the usual metachronal waves. The synchronized beating yields high initial accelerations but requires the cell to coast through the synchrnized recovery. Finally, escape from a life-threatening agression is achieved by a "jumping" gait which does not rely on the cilia but is achieved from the explosive release of a rod-like organelles in the direction of the hot spot. Measurements through high-speed video explain the role of these rods in defending Paramecium. They also show that the zero-Reynolds number assumption is unverified in most cases.

  5. Feeding of swimming Paramecium with fore-aft asymmetry in viscous fluid

    Science.gov (United States)

    Zhang, Peng; Jana, Saikat; Giarra, Matthew; Vlachos, Pavlos; Jung, Sunghwan

    2013-11-01

    Swimming behaviours and feeding efficiencies of Paramecium Multimicronucleatum with fore-aft asymmetric body shapes are studied experimentally and numerically. Among various possible swimming ways, ciliates typically exhibit only one preferred swimming directions in favorable conditions. Ciliates, like Paramecia, with fore-aft asymmetric shapes preferably swim towards the slender anterior while feeding fluid to the oral groove located at the center of the body. Since both feeding and swimming efficiencies are influenced by fluid motions around the body, it is important to reveal the fluid mechanics around a moving object. Experimentally, μ-PIV methods are employed to characterize the source-dipole streamline patterns and fluid motions around Paramecium. Numerical simulations by boundary element methods are also used to evaluate surface stresses and velocities, which give insights into the efficiencies of swimming and feeding depending on body asymmetry. It is concluded that a slender anterior and fat posterior increases the combined efficiency of swimming and feeding, which matches well with actual shapes of Paramecium. Discrepancies between experiments and simulations are also discussed.

  6. Hierarchical paramecium-like hollow and solid Au/Pt bimetallic nanostructures constructed using goethite as template

    Energy Technology Data Exchange (ETDEWEB)

    Liu Wei; Repo, Eveliina; Sillanpaeae, Mika [Laboratory of Applied Environmental Chemistry, University of Eastern Finland, Patteristonkatu 1, FI-50100 Mikkeli (Finland); Heikkilae, Mikko; Leskelae, Markku, E-mail: weiliuzk@yahoo.cn, E-mail: mika.sillanpaa@uef.fi [Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, PO Box 55 (A.I. Virtasen aukio 1), FI-00014, Helsinki (Finland)

    2010-10-01

    Novel hollow and solid paramecium-like hierarchical Au/Pt bimetallic nanostructures were constructed using goethite as template via a seed-mediated growth method. Transmission electron microscopy (TEM), {xi}-potential measurement, UV-vis spectroscopy, energy dispersive x-ray spectroscopy (EDS), ICP-AES measurement, x-ray powder diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) were utilized to systematically characterize the bimetallic nanostructures. It is found that the core structure of the paramecium-like bimetallic nanomaterial is closely related to reducing agent. When ascorbic acid is used as reducing agent, goethite serves as in situ sacrificed template and hollow paramecium-like bimetallic structure is obtained. When NH{sub 2}OH{center_dot}HCl is used, solid nanostructure with preserved goethite core is produced. Heating the reaction solution is necessary to obtain the paramecium-like morphology with rough interconnected Pt cilia shell. The thickness of Pt cilia layer can be controlled by adjusting the molar ratio of H{sub 2}PtCl{sub 6} to Au nanoseeds. The overgrowth of the rough Pt cilia is proposed to be via an autocatalytic and three-dimensional heterogeneous nucleation process first through flower-like morphology. Both the hollow and solid hierarchical paramecium-like Au/Pt bimetallic nanostructures show good catalytic activities.

  7. Gamma-amino butyric acid (GABA) release in the ciliated protozoon Paramecium occurs by neuronal-like exocytosis.

    Science.gov (United States)

    Ramoino, P; Milanese, M; Candiani, S; Diaspro, A; Fato, M; Usai, C; Bonanno, G

    2010-04-01

    Paramecium primaurelia expresses a significant amount of gamma-amino butyric acid (GABA). Paramecia possess both glutamate decarboxylase (GAD)-like and vesicular GABA transporter (vGAT)-like proteins, indicating the ability to synthesize GABA from glutamate and to transport GABA into vesicles. Using antibodies raised against mammalian GAD and vGAT, bands with an apparent molecular weight of about 67 kDa and 57 kDa were detected. The presence of these bands indicated a similarity between the proteins in Paramecium and in mammals. VAMP, syntaxin and SNAP, putative proteins of the release machinery that form the so-called SNARE complex, are present in Paramecium. Most VAMP, syntaxin and SNAP fluorescence is localized in spots that vary in size and density and are primarily distributed near the plasma membrane. Antibodies raised against mammal VAMP-3, sintaxin-1 or SNAP-25 revealed protein immunoblot bands having molecular weights consistent with those observed in mammals. Moreover, P. primaurelia spontaneously releases GABA into the environment, and this neurotransmitter release significantly increases after membrane depolarization. The depolarization-induced GABA release was strongly reduced not only in the absence of extracellular Ca(2+) but also by pre-incubation with bafilomycin A1 or with botulinum toxin C1 serotype. It can be concluded that GABA occurs in Paramecium, where it is probably stored in vesicles capable of fusion with the cell membrane; accordingly, GABA can be released from Paramecium by stimulus-induced, neuronal-like exocytotic mechanisms.

  8. Hierarchical paramecium-like hollow and solid Au/Pt bimetallic nanostructures constructed using goethite as template

    International Nuclear Information System (INIS)

    Liu Wei; Repo, Eveliina; Sillanpaeae, Mika; Heikkilae, Mikko; Leskelae, Markku

    2010-01-01

    Novel hollow and solid paramecium-like hierarchical Au/Pt bimetallic nanostructures were constructed using goethite as template via a seed-mediated growth method. Transmission electron microscopy (TEM), ξ-potential measurement, UV-vis spectroscopy, energy dispersive x-ray spectroscopy (EDS), ICP-AES measurement, x-ray powder diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) were utilized to systematically characterize the bimetallic nanostructures. It is found that the core structure of the paramecium-like bimetallic nanomaterial is closely related to reducing agent. When ascorbic acid is used as reducing agent, goethite serves as in situ sacrificed template and hollow paramecium-like bimetallic structure is obtained. When NH 2 OH·HCl is used, solid nanostructure with preserved goethite core is produced. Heating the reaction solution is necessary to obtain the paramecium-like morphology with rough interconnected Pt cilia shell. The thickness of Pt cilia layer can be controlled by adjusting the molar ratio of H 2 PtCl 6 to Au nanoseeds. The overgrowth of the rough Pt cilia is proposed to be via an autocatalytic and three-dimensional heterogeneous nucleation process first through flower-like morphology. Both the hollow and solid hierarchical paramecium-like Au/Pt bimetallic nanostructures show good catalytic activities.

  9. Hierarchical paramecium-like hollow and solid Au/Pt bimetallic nanostructures constructed using goethite as template

    Science.gov (United States)

    Liu, Wei; Repo, Eveliina; Heikkilä, Mikko; Leskelä, Markku; Sillanpää, Mika

    2010-10-01

    Novel hollow and solid paramecium-like hierarchical Au/Pt bimetallic nanostructures were constructed using goethite as template via a seed-mediated growth method. Transmission electron microscopy (TEM), ξ-potential measurement, UV-vis spectroscopy, energy dispersive x-ray spectroscopy (EDS), ICP-AES measurement, x-ray powder diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) were utilized to systematically characterize the bimetallic nanostructures. It is found that the core structure of the paramecium-like bimetallic nanomaterial is closely related to reducing agent. When ascorbic acid is used as reducing agent, goethite serves as in situ sacrificed template and hollow paramecium-like bimetallic structure is obtained. When NH2OH·HCl is used, solid nanostructure with preserved goethite core is produced. Heating the reaction solution is necessary to obtain the paramecium-like morphology with rough interconnected Pt cilia shell. The thickness of Pt cilia layer can be controlled by adjusting the molar ratio of H2PtCl6 to Au nanoseeds. The overgrowth of the rough Pt cilia is proposed to be via an autocatalytic and three-dimensional heterogeneous nucleation process first through flower-like morphology. Both the hollow and solid hierarchical paramecium-like Au/Pt bimetallic nanostructures show good catalytic activities.

  10. Delimiting Species Boundaries within a Paraphyletic Species Complex: Insights from Morphological, Genetic, and Molecular Data on Paramecium sonneborni (Paramecium aurelia species complex, Ciliophora, Protozoa).

    Science.gov (United States)

    Przyboś, Ewa; Tarcz, Sebastian; Rautian, Maria; Sawka, Natalia

    2015-09-01

    The demarcation of boundaries between protist species is often problematic because of the absence of a uniform species definition, the abundance of cryptic diversity, and the occurrence of convergent morphology. The ciliates belonging to the Paramecium aurelia complex, consisting of 15 species, are a good model for such systematic and evolutionary studies. One member of the complex is P. sonneborni, previously known only from one stand in Texas (USA), but recently found in two new sampling sites in Cyprus (creeks running to Salt Lake and Oroklini Lake near Larnaca). The studied Paramecium sonneborni strains (from the USA and Cyprus) reveal low viability in the F1 and F2 generations of interstrain hybrids and may be an example of ongoing allopatric speciation. Despite its molecular distinctiveness, we postulate that P. sonneborni should remain in the P. aurelia complex, making it a paraphyletic taxon. Morphological studies have revealed that some features of the nuclear apparatus of P. sonneborni correspond to the P. aurelia spp. complex, while others are similar to P. jenningsi and P. schewiakoffi. The observed discordance indicates rapid splitting of the P. aurelia-P. jenningsi-P. schewiakoffi group, in which genetic, morphological, and molecular boundaries between species are not congruent. Copyright © 2015 Elsevier GmbH. All rights reserved.

  11. Pharmacological characterization of NMDA-like receptors in the single-celled organism Paramecium primaurelia.

    Science.gov (United States)

    Ramoino, Paola; Candiani, Simona; Pittaluga, Anna Maria; Usai, Cesare; Gallus, Lorenzo; Ferrando, Sara; Milanese, Marco; Faimali, Marco; Bonanno, Giambattista

    2014-02-01

    Paramecium primaurelia is a unicellular eukaryote that moves in freshwater by ciliary beating and responds to environmental stimuli by altering motile behaviour. The movements of the cilia are controlled by the electrical changes of the cell membrane: when the intraciliary Ca(2+) concentration associated with plasma membrane depolarization increases, the ciliary beating reverses its direction, and consequently the swimming direction changes. The ciliary reversal duration is correlated with the amount of Ca(2+) influx. Here, we evaluated the effects due to the activation or blockade of N-methyl-d-aspartic acid (NMDA) receptors on swimming behaviour in Paramecium. Paramecia normally swim forward, drawing almost linear tracks. We observed that the simultaneous administration of NMDA and glycine induced a partial ciliary reversal (PaCR) leading to a continuous spiral-like swim. Furthermore, the duration of continuous ciliary reversal (CCR), triggered by high external KCl concentrations, was longer in NMDA+glycine-treated cells. NMDA action required the presence of Ca(2+), as the normal forward swimming was restored when the ion was omitted from the extracellular milieu. The PaCR and the enhancement of CCR duration significantly decreased when the antagonists of the glutamate site D-AP5 or CGS19755, the NMDA channel blocker MK-801 or the glycine site antagonist DCKA was added. The action of NMDA+glycine was also abolished by Zn(2+) or ifenprodil, the GluN2A and the GluN2B NMDA-containing subunit blockers, respectively. Searches of the Paramecium genome database currently available indicate that the NMDA-like receptor with ligand-binding characteristics of an NMDA receptor-like complex, purified from rat brain synaptic membranes and found in some metazoan genomes, is also present in Paramecium. These results provide evidence that functional NMDA receptors similar to those typical of mammalian neuronal cells are present in the single-celled organism Paramecium and thus

  12. Fuel From Algae: Scaling and Commercialization of Algae Harvesting Technologies

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-01-15

    Broad Funding Opportunity Announcement Project: Led by CEO Ross Youngs, AVS has patented a cost-effective dewatering technology that separates micro-solids (algae) from water. Separating micro-solids from water traditionally requires a centrifuge, which uses significant energy to spin the water mass and force materials of different densities to separate from one another. In a comparative analysis, dewatering 1 ton of algae in a centrifuge costs around $3,400. AVS’s Solid-Liquid Separation (SLS) system is less energy-intensive and less expensive, costing $1.92 to process 1 ton of algae. The SLS technology uses capillary dewatering with filter media to gently facilitate water separation, leaving behind dewatered algae which can then be used as a source for biofuels and bio-products. The biomimicry of the SLS technology emulates the way plants absorb and spread water to their capillaries.

  13. Shewanella algae in acute gastroenteritis

    Directory of Open Access Journals (Sweden)

    S Dey

    2015-01-01

    Full Text Available Shewanella algae is an emerging bacteria rarely implicated as a human pathogen. Previously reported cases of S. algae have mainly been associated with direct contact with seawater. Here we report the isolation of S. algae as the sole etiological agent from a patient suffering from acute gastroenteritis with bloody diarrhoea. The bacterium was identified by automated identification system and 16S rRNA gene sequence analysis. Our report highlights the importance of looking for the relatively rare aetiological agents in clinical samples that does not yield common pathogens. It also underscores the usefulness of automated systems in identification of rare pathogens.

  14. Transgenic algae engineered for higher performance

    Science.gov (United States)

    Unkefer, Pat J; Anderson, Penelope S; Knight, Thomas J

    2014-10-21

    The present disclosure relates to transgenic algae having increased growth characteristics, and methods of increasing growth characteristics of algae. In particular, the disclosure relates to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and a glutamine synthetase.

  15. Calcium-release channels in paramecium. Genomic expansion, differential positioning and partial transcriptional elimination.

    Directory of Open Access Journals (Sweden)

    Eva-Maria Ladenburger

    Full Text Available The release of Ca²⁺ from internal stores is a major source of signal Ca²⁺ in almost all cell types. The internal Ca²⁺ pools are activated via two main families of intracellular Ca²⁺-release channels, the ryanodine and the inositol 1,4,5-trisphosphate (InsP₃ receptors. Among multicellular organisms these channel types are ubiquitous, whereas in most unicellular eukaryotes the identification of orthologs is impaired probably due to evolutionary sequence divergence. However, the ciliated protozoan Paramecium allowed us to prognosticate six groups, with a total of 34 genes, encoding proteins with characteristics typical of InsP₃ and ryanodine receptors by BLAST search of the Paramecium database. We here report that these Ca²⁺-release channels may display all or only some of the characteristics of canonical InsP₃ and ryanodine receptors. In all cases, prediction methods indicate the presence of six trans-membrane regions in the C-terminal domains, thus corresponding to canonical InsP₃ receptors, while a sequence homologous to the InsP₃-binding domain is present only in some types. Only two types have been analyzed in detail previously. We now show, by using antibodies and eventually by green fluorescent protein labeling, that the members of all six groups localize to distinct organelles known to participate in vesicle trafficking and, thus, may provide Ca²⁺ for local membrane-membrane interactions. Whole genome duplication can explain radiation within the six groups. Comparative and evolutionary evaluation suggests derivation from a common ancestor of canonical InsP₃ and ryanodine receptors. With one group we could ascertain, to our knowledge for the first time, aberrant splicing in one thoroughly analyzed Paramecium gene. This yields truncated forms and, thus, may indicate a way to pseudogene formation. No comparable analysis is available for any other, free-living or parasitic/pathogenic protozoan.

  16. Calcium-Release Channels in Paramecium. Genomic Expansion, Differential Positioning and Partial Transcriptional Elimination

    Science.gov (United States)

    Ladenburger, Eva-Maria; Plattner, Helmut

    2011-01-01

    The release of Ca2+ from internal stores is a major source of signal Ca2+ in almost all cell types. The internal Ca2+ pools are activated via two main families of intracellular Ca2+-release channels, the ryanodine and the inositol 1,4,5-trisphosphate (InsP3) receptors. Among multicellular organisms these channel types are ubiquitous, whereas in most unicellular eukaryotes the identification of orthologs is impaired probably due to evolutionary sequence divergence. However, the ciliated protozoan Paramecium allowed us to prognosticate six groups, with a total of 34 genes, encoding proteins with characteristics typical of InsP3 and ryanodine receptors by BLAST search of the Paramecium database. We here report that these Ca2+-release channels may display all or only some of the characteristics of canonical InsP3 and ryanodine receptors. In all cases, prediction methods indicate the presence of six trans-membrane regions in the C-terminal domains, thus corresponding to canonical InsP3 receptors, while a sequence homologous to the InsP3-binding domain is present only in some types. Only two types have been analyzed in detail previously. We now show, by using antibodies and eventually by green fluorescent protein labeling, that the members of all six groups localize to distinct organelles known to participate in vesicle trafficking and, thus, may provide Ca2+ for local membrane-membrane interactions. Whole genome duplication can explain radiation within the six groups. Comparative and evolutionary evaluation suggests derivation from a common ancestor of canonical InsP3 and ryanodine receptors. With one group we could ascertain, to our knowledge for the first time, aberrant splicing in one thoroughly analyzed Paramecium gene. This yields truncated forms and, thus, may indicate a way to pseudogene formation. No comparable analysis is available for any other, free-living or parasitic/pathogenic protozoan. PMID:22102876

  17. Ligand binding in the ferric and ferrous states of Paramecium hemoglobin.

    Science.gov (United States)

    Das, T K; Weber, R E; Dewilde, S; Wittenberg, J B; Wittenberg, B A; Yamauchi, K; Van Hauwaert, M L; Moens, L; Rousseau, D L

    2000-11-21

    The unicellular protozoan Paramecium caudatum contains a monomeric hemoglobin (Hb) that has only 116 amino acid residues. This Hb shares the simultaneous presence of a distal E7 glutamine and a B10 tyrosine with several invertebrate Hbs. In the study presented here, we have used ligand binding kinetics and resonance Raman spectroscopy to characterize the effect of the distal pocket residues of Paramecium Hb in stabilizing the heme-bound ligands. In the ferric state, the high-spin to low-spin (aquo-hydroxy) transition takes place with a pK(a) of approximately 9.0. The oxygen affinity (P(50) = 0.45 Torr) is similar to that of myoglobin. The oxygen on- and off-rates are also similar to those of sperm whale myoglobin. Resonance Raman data suggest hydrogen bonding stabilization of bound oxygen, evidenced by a relatively low frequency of Fe-OO stretching (563 cm(-1)). We propose that the oxy complex is an equilibrium mixture of a hydrogen-bonded closed structure and an open structure. Oxygen will dissociate preferentially from the open structure, and therefore, the fraction of open structure population controls the rate of oxygen dissociation. In the CO complex, the Fe-CO stretching frequency at 493 cm(-1) suggests an open heme pocket, which is consistent with the higher on- and off-rates for CO relative to those in myoglobin. A high rate of ligand binding is also consistent with the observation of an Fe-histidine stretching frequency at 220 cm(-1), indicating the absence of significant proximal strain. We postulate that the function of Paramecium Hb is to supply oxygen for cellular oxidative processes.

  18. The ciliate Paramecium shows higher motility in non-uniform chemical landscapes.

    Directory of Open Access Journals (Sweden)

    Carl Giuffre

    Full Text Available We study the motility behavior of the unicellular protozoan Paramecium tetraurelia in a microfluidic device that can be prepared with a landscape of attracting or repelling chemicals. We investigate the spatial distribution of the positions of the individuals at different time points with methods from spatial statistics and Poisson random point fields. This makes quantitative the informal notion of "uniform distribution" (or lack thereof. Our device is characterized by the absence of large systematic biases due to gravitation and fluid flow. It has the potential to be applied to the study of other aquatic chemosensitive organisms as well. This may result in better diagnostic devices for environmental pollutants.

  19. The Ciliate Paramecium Shows Higher Motility in Non-Uniform Chemical Landscapes

    Science.gov (United States)

    Giuffre, Carl; Hinow, Peter; Vogel, Ryan; Ahmed, Tanvir; Stocker, Roman; Consi, Thomas R.; Strickler, J. Rudi

    2011-01-01

    We study the motility behavior of the unicellular protozoan Paramecium tetraurelia in a microfluidic device that can be prepared with a landscape of attracting or repelling chemicals. We investigate the spatial distribution of the positions of the individuals at different time points with methods from spatial statistics and Poisson random point fields. This makes quantitative the informal notion of “uniform distribution” (or lack thereof). Our device is characterized by the absence of large systematic biases due to gravitation and fluid flow. It has the potential to be applied to the study of other aquatic chemosensitive organisms as well. This may result in better diagnostic devices for environmental pollutants. PMID:21494596

  20. Algae biotechnology: products and processes

    National Research Council Canada - National Science Library

    Bux, F; Chisti, Yusuf

    2016-01-01

    This book examines the utilization of algae for the development of useful products and processes with the emphasis towards green technologies and processes, and the requirements to make these viable...

  1. Algae: America's Pathway to Independence

    National Research Council Canada - National Science Library

    Custer, James

    2007-01-01

    .... Oil dependency is an unacceptable risk to U.S. national strategy. This paper advocates independence from foreign oil by converting the national transportation fleet to biodiesel derived from algae...

  2. Biological importance of marine algae.

    Science.gov (United States)

    El Gamal, Ali A

    2010-01-01

    Marine organisms are potentially prolific sources of highly bioactive secondary metabolites that might represent useful leads in the development of new pharmaceutical agents. Algae can be classified into two main groups; first one is the microalgae, which includes blue green algae, dinoflagellates, bacillariophyta (diatoms)… etc., and second one is macroalgae (seaweeds) which includes green, brown and red algae. The microalgae phyla have been recognized to provide chemical and pharmacological novelty and diversity. Moreover, microalgae are considered as the actual producers of some highly bioactive compounds found in marine resources. Red algae are considered as the most important source of many biologically active metabolites in comparison to other algal classes. Seaweeds are used for great number of application by man. The principal use of seaweeds as a source of human food and as a source of gums (phycocollides). Phycocolloides like agar agar, alginic acid and carrageenan are primarily constituents of brown and red algal cell walls and are widely used in industry.

  3. A synthetic cadmium metallothionein gene (PMCd1syn) of Paramecium species: expression, purification and characteristics of metallothionein protein.

    Science.gov (United States)

    Dar, Saira; Shuja, Rukhsana N; Shakoori, Abdul Rauf

    2013-02-01

    Metallothioneins (MTs) are metal binding proteins that are rich in cysteine residues constituting 10-30 % of the total protein, and in which the thiol groups bind to the metal ions. The increasing amount of metal ions in the medium have shown increased production of MTs by different organisms such as bacteria, protozoa and mammals like humans. PMCd1 is the first gene ever discovered in Paramecium, a ciliated protozoan, that could produce this MT in response to cadmium. In this study the PMCd1syn gene has been cloned in pET41a expression vector and expressed in an Escherichia coli BL21-codonplus strain for the first time. Since the gene PMCd1 amplified from Paramecium contained 10 codons, which could act as stop codons during expression in E. coli, this gene of 612 bps was synthesized to substitute these (stop) codons for the Paramecium sp. specific amino acids. For stability of the expressed protein, glutathione-S-transferase gene was fused with PMCd1syn gene and coexpressed. The cells expressing PMCd1syn demonstrated increased accumulation of cadmium. This is the first report of cadmium MT protein expressed from Paramecium species, particularly from synthetic MT gene (PMCd1syn). This fusion protein, the molecular weight of which has been confirmed to be 53.03 kDa with MALDI analysis, is rich in cysteine residues, and has been shown for the first time in this ciliate to bind to and sequester Cd(2+)-ions.

  4. Multiple lines of evidence shed light on the occurrence of paramecium (ciliophora, oligohymenophorea) in bromeliad tank water.

    Science.gov (United States)

    Buosi, Paulo R B; Cabral, Adalgisa F; Simão, Taiz L L; Utz, Laura R P; Velho, Luiz F M

    2014-01-01

    Phytotelmata are vegetal structures that hold water from the rain, and organic matter from the forest and the soil, resulting in small, compartmentalized bodies of water, which provide an essential environment for the establishment and development of many organisms. These microenvironments generally harbor endemic species, but many organisms that are found in lakes and rivers, are also present. Here, we report, for the first time, the occurrence of the ciliate genus Paramecium in the tank of the bromeliad species Aechmaea distichantha. The identification of the Paramecium species was performed based on live observations, protargol impregnation, scanning electronic microscopy, and sequencing of the 18s rRNA. The absence of Paramecium from bromeliad tank water was highlighted in several earlier investigations, and may be due to the fact that this species is unable to make cysts. The occurrence of Paramecium multimicronucleatum in our samples may be explained by the proximity between the bromeliads and the river, a potential source of the species. Further, we also believe that the counting methodology used in our study provides a more accurate analysis of the species diversity, since we investigated all samples within a maximum period of 6 h after sampling, allowing minimum loss of specimens. © 2013 The Author(s) Journal of Eukaryotic Microbiology © 2013 International Society of Protistologists.

  5. Paramecium tetraurelia pre-screen for hazardous chemicals: a rapid detector system for health hazards. 1977-1983 report

    Energy Technology Data Exchange (ETDEWEB)

    Smith-Sonneborn, J.

    1983-01-01

    The purpose was to develop and validate a new eukaryotic bioassay system applicable to rapid identification of environmental toxins, mutagens, and carcinogens. The ability of Paramecium to detect potential health hazards, associated with complex environmental mixtures, was demonstrated in association with the finest coal fly ash particles and aqueous waste streams from both oil shale and coal gasification developing technologies. In Paramecium, the cytotoxicity of an agent was determined by altering the survival and/or growth rate of single cells in test agents. Genotoxicity was assayed by a two-tiered approach, utilizing both the Paramecium system and the more established Ames Salmonella assay for mutagen/carcinogen detection. An agent was considered genotoxic in Paramwecium if altered phenotypes were induced in the fertilization progeny of treated parent cells. Since others had shown a significant correlation between agents which were photodynamically active in Paramecium and carcinogenic in mammals, the photodynamic activity versus carcinogenicity of agents was reviewed. Photodynamically active compounds are defined by the immobilization of cells when exposed to both the test agent and black light; neither the agent alone nor light alone affects swimming activity.

  6. Centrin diversity and basal body patterning across evolution: new insights from Paramecium

    Directory of Open Access Journals (Sweden)

    Anne Aubusson-Fleury

    2017-06-01

    Full Text Available First discovered in unicellular eukaryotes, centrins play crucial roles in basal body duplication and anchoring mechanisms. While the evolutionary status of the founding members of the family, Centrin2/Vfl2 and Centrin3/cdc31 has long been investigated, the evolutionary origin of other members of the family has received less attention. Using a phylogeny of ciliate centrins, we identify two other centrin families, the ciliary centrins and the centrins present in the contractile filaments (ICL centrins. In this paper, we carry on the functional analysis of still not well-known centrins, the ICL1e subfamily identified in Paramecium, and show their requirement for correct basal body anchoring through interactions with Centrin2 and Centrin3. Using Paramecium as well as a eukaryote-wide sampling of centrins from completely sequenced genomes, we revisited the evolutionary story of centrins. Their phylogeny shows that the centrins associated with the ciliate contractile filaments are widespread in eukaryotic lineages and could be as ancient as Centrin2 and Centrin3.

  7. Insights into three whole-genome duplications gleaned from the Paramecium caudatum genome sequence.

    Science.gov (United States)

    McGrath, Casey L; Gout, Jean-Francois; Doak, Thomas G; Yanagi, Akira; Lynch, Michael

    2014-08-01

    Paramecium has long been a model eukaryote. The sequence of the Paramecium tetraurelia genome reveals a history of three successive whole-genome duplications (WGDs), and the sequences of P. biaurelia and P. sexaurelia suggest that these WGDs are shared by all members of the aurelia species complex. Here, we present the genome sequence of P. caudatum, a species closely related to the P. aurelia species group. P. caudatum shares only the most ancient of the three WGDs with the aurelia complex. We found that P. caudatum maintains twice as many paralogs from this early event as the P. aurelia species, suggesting that post-WGD gene retention is influenced by subsequent WGDs and supporting the importance of selection for dosage in gene retention. The availability of P. caudatum as an outgroup allows an expanded analysis of the aurelia intermediate and recent WGD events. Both the Guanine+Cytosine (GC) content and the expression level of preduplication genes are significant predictors of duplicate retention. We find widespread asymmetrical evolution among aurelia paralogs, which is likely caused by gradual pseudogenization rather than by neofunctionalization. Finally, cases of divergent resolution of intermediate WGD duplicates between aurelia species implicate this process acts as an ongoing reinforcement mechanism of reproductive isolation long after a WGD event. Copyright © 2014 by the Genetics Society of America.

  8. Epigenetic regulation of serotype expression antagonizes transcriptome dynamics in Paramecium tetraurelia.

    Science.gov (United States)

    Cheaib, Miriam; Dehghani Amirabad, Azim; Nordström, Karl J V; Schulz, Marcel H; Simon, Martin

    2015-08-01

    Phenotypic variation of a single genotype is achieved by alterations in gene expression patterns. Regulation of such alterations depends on their time scale, where short-time adaptations differ from permanently established gene expression patterns maintained by epigenetic mechanisms. In the ciliate Paramecium, serotypes were described for an epigenetically controlled gene expression pattern of an individual multigene family. Paradoxically, individual serotypes can be triggered in Paramecium by alternating environments but are then stabilized by epigenetic mechanisms, thus raising the question to which extend their expression follows environmental stimuli. To characterize environmental adaptation in the context of epigenetically controlled serotype expression, we used RNA-seq to characterize transcriptomes of serotype pure cultures. The resulting vegetative transcriptome resource is first analysed for genes involved in the adaptive response to the altered environment. Secondly, we identified groups of genes that do not follow the adaptive response but show co-regulation with the epigenetically controlled serotype system, suggesting that their gene expression pattern becomes manifested by similar mechanisms. In our experimental set-up, serotype expression and the entire group of co-regulated genes were stable among environmental changes and only heat-shock genes altered expression of these gene groups. The data suggest that the maintenance of these gene expression patterns in a lineage represents epigenetically controlled robustness counteracting short-time adaptation processes. © The Author 2015. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  9. Ciliary metachronal wave propagation on the compliant surface of Paramecium cells.

    Science.gov (United States)

    Narematsu, Naoki; Quek, Raymond; Chiam, Keng-Hwee; Iwadate, Yoshiaki

    2015-12-01

    Ciliary movements in protozoa exhibit metachronal wave-like coordination, in which a constant phase difference is maintained between adjacent cilia. It is at present generally thought that metachronal waves require hydrodynamic coupling between adjacent cilia and the extracellular fluid. To test this hypothesis, we aspirated a Paramecium cell using a micropipette which completely sealed the surface of the cell such that no fluid could pass through the micropipette. Thus, the anterior and the posterior regions of the cell were hydrodynamically decoupled. Nevertheless, we still observed that metachronal waves continued to propagate from the anterior to the posterior ends of the cell, suggesting that in addition to hydrodynamic coupling, there are other mechanisms that can also transmit the metachronal waves. Such transmission was also observed in computational modeling where the fluid was fully decoupled between two partitions of a beating ciliary array. We also imposed cyclic stretching on the surface of live Paramecium cells and found that metachronal waves persisted in the presence of cyclic stretching. This demonstrated that, in addition to hydrodynamic coupling, a compliant substrate can also play a critical role in mediating the propagation of metachronal waves. © 2015 Wiley Periodicals, Inc.

  10. Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum

    Science.gov (United States)

    Fujiwara, Yoshihisa; Tomishige, Masahiko; Itoh, Yasuhiro; Fujiwara, Masao; Shibata, Naho; Kosaka, Toshikazu; Hosoya, Hiroshi; Tanimoto, Yoshifumi

    2006-05-01

    Effect of horizontal strong static magnetic field on swimming behaviour of Paramecium caudatum was studied by using a superconducting magnet. Around a centre of a round vessel, random swimming at 0 T and aligned swimming parallel to the magnetic field (MF) of 8 T were observed. Near a wall of the vessel, however, swimming round and round along the wall at 0 T and aligned swimming of turning at right angles upon collision with the wall, which was remarkable around 1-4 T, were detected. It was experimentally revealed that the former MF-induced parallel swimming at the vessel centre was caused physicochemically by the parallel magnetic orientation of the cell itself. From magnetic field dependence of the extent of the orientation, the magnetic susceptibility anisotropy (χ ∥-χ ⊥) was first obtained to be 3.4× 10-23 emu cell-1 at 298 K for Paramecium caudatum. The orientation of the cell was considered to result from the magnetic orientation of the cell membrane. On the other hand, although mechanisms of the latter swimming near the vessel wall regardless of the absence and presence of the magnetic field are unclear at present, these experimental results indicate that whether the cell exists near the wall alters the magnetic field effect on the swimming in the horizontal magnetic field.

  11. A forward genetic screen reveals essential and non-essential RNAi factors in Paramecium tetraurelia

    Science.gov (United States)

    Marker, Simone; Carradec, Quentin; Tanty, Véronique; Arnaiz, Olivier; Meyer, Eric

    2014-01-01

    In most eukaryotes, small RNA-mediated gene silencing pathways form complex interacting networks. In the ciliate Paramecium tetraurelia, at least two RNA interference (RNAi) mechanisms coexist, involving distinct but overlapping sets of protein factors and producing different types of short interfering RNAs (siRNAs). One is specifically triggered by high-copy transgenes, and the other by feeding cells with double-stranded RNA (dsRNA)-producing bacteria. In this study, we designed a forward genetic screen for mutants deficient in dsRNA-induced silencing, and a powerful method to identify the relevant mutations by whole-genome sequencing. We present a set of 47 mutant alleles for five genes, revealing two previously unknown RNAi factors: a novel Paramecium-specific protein (Pds1) and a Cid1-like nucleotidyl transferase. Analyses of allelic diversity distinguish non-essential and essential genes and suggest that the screen is saturated for non-essential, single-copy genes. We show that non-essential genes are specifically involved in dsRNA-induced RNAi while essential ones are also involved in transgene-induced RNAi. One of the latter, the RNA-dependent RNA polymerase RDR2, is further shown to be required for all known types of siRNAs, as well as for sexual reproduction. These results open the way for the dissection of the genetic complexity, interconnection, mechanisms and natural functions of RNAi pathways in P. tetraurelia. PMID:24860163

  12. Algae-Based Carbon Sequestration

    Science.gov (United States)

    Haoyang, Cai

    2018-03-01

    Our civilization is facing a series of environmental problems, including global warming and climate change, which are caused by the accumulation of green house gases in the atmosphere. This article will briefly analyze the current global warming problem and propose a method that we apply algae cultivation to absorb carbon and use shellfish to sequestrate it. Despite the importance of decreasing CO2 emissions or developing carbon-free energy sources, carbon sequestration should be a key issue, since the amount of carbon dioxide that already exists in the atmosphere is great enough to cause global warming. Algae cultivation would be a good choice because they have high metabolism rates and provides shellfish with abundant food that contains carbon. Shellfish’s shells, which are difficult to be decomposed, are reliable storage of carbon, compared to dead organisms like trees and algae. The amount of carbon that can be sequestrated by shellfish is considerable. However, the sequestrating rate of algae and shellfish is not high enough to affect the global climate. Research on algae and shellfish cultivation, including gene technology that aims to create “super plants” and “super shellfish”, is decisive to the solution. Perhaps the baton of history will shift to gene technology, from nuclear physics that has lost appropriate international environment after the end of the Cold War. Gene technology is vital to human survival.

  13. Algae Bloom in a Lake

    Directory of Open Access Journals (Sweden)

    David Sanabria

    2008-01-01

    Full Text Available The objective of this paper is to determine the likelihood of an algae bloom in a particular lake located in upstate New York. The growth of algae in this lake is caused by a high concentration of phosphorous that diffuses to the surface of the lake. Our calculations, based on Fick's Law, are used to create a mathematical model of the driving force of diffusion for phosphorous. Empirical observations are also used to predict whether the concentration of phosphorous will diffuse to the surface of this lake within a specified time and under specified conditions.

  14. Differences in infectivity between endosymbiotic Chlorella variabilis cultivated outside host Paramecium bursaria for 50 years and those immediately isolated from host cells after one year of reendosymbiosis

    Directory of Open Access Journals (Sweden)

    Y. Kodama

    2016-01-01

    Full Text Available Chlorella variabilis strain NC64A is an intracellular photobiont of the ciliate Paramecium bursaria. NC64A was isolated from P. bursaria nearly 50 years ago and was thereafter cultivated outside the host. This study was undertaken to detect changes in its infectivity to P. bursaria and its auxotrophy for growth outside the host induced during long-term cultivation. NC64A can grow in Modified Bold's Basal Medium but not in C medium, whereas another symbiotic Chlorella variabilis strain, 1N, that was recently isolated from the host grew in C medium but not in Modified Bold's Basal Medium. With regards infectivity, NC64A in the logarithmic phase of growth showed low infectivity to alga-removed P. bursaria cells, whereas those in the early stationary phase showed high infectivity of about 30%. Those in the decay phase of growth showed no infectivity. Results show that NC64A has infectivity, but the infection rate depends on their culture age in the growth curve. Furthermore, NC64A that had been re-infected to P. bursaria for more than one year and isolated from the host showed a nearly 100% infection rate, which indicates that NC64A can recover its infectivity by re-infection to P. bursaria.

  15. Microscopic Gardens: A Close Look at Algae.

    Science.gov (United States)

    Foote, Mary Ann

    1983-01-01

    Describes classroom activities using algae, including demonstration of eutrophication, examination of mating strains, and activities with Euglena. Includes on algal morphology/physiology, types of algae, and field sources for collecting these organisms. (JN)

  16. Formation of algae growth constitutive relations for improved algae modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Gharagozloo, Patricia E.; Drewry, Jessica Louise.

    2013-01-01

    This SAND report summarizes research conducted as a part of a two year Laboratory Directed Research and Development (LDRD) project to improve our abilities to model algal cultivation. Algae-based biofuels have generated much excitement due to their potentially large oil yield from relatively small land use and without interfering with the food or water supply. Algae mitigate atmospheric CO2 through metabolism. Efficient production of algal biofuels could reduce dependence on foreign oil by providing a domestic renewable energy source. Important factors controlling algal productivity include temperature, nutrient concentrations, salinity, pH, and the light-to-biomass conversion rate. Computational models allow for inexpensive predictions of algae growth kinetics in these non-ideal conditions for various bioreactor sizes and geometries without the need for multiple expensive measurement setups. However, these models need to be calibrated for each algal strain. In this work, we conduct a parametric study of key marine algae strains and apply the findings to a computational model.

  17. 21 CFR 184.1120 - Brown algae.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Brown algae. 184.1120 Section 184.1120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1120 Brown algae. (a) Brown algae are seaweeds of the species Analipus...

  18. 21 CFR 184.1121 - Red algae.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Red algae. 184.1121 Section 184.1121 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species Gloiopeltis...

  19. Scenario studies for algae production

    NARCIS (Netherlands)

    Slegers, P.M.

    2014-01-01

    Microalgae are a promising biomass for the biobased economy to produce food, feed, fuel, chemicals and materials. So far, large-scale production of algae is limited and as a result estimates on the performance of such large systems are scarce. There is a need to estimate large-scale biomass

  20. Algae. LC Science Tracer Bullet.

    Science.gov (United States)

    Niskern, Diana, Comp.

    The plants and plantlike organisms informally grouped together as algae show great diversity of form and size and occur in a wide variety of habitats. These extremely important photosynthesizers are also economically significant. For example, some species contaminate water supplies; others provide food for aquatic animals and for man; still others…

  1. The influence of local UV irradiation of the generative nucleus on vegetative function of Paramecium putrinum

    International Nuclear Information System (INIS)

    Fokin, S.I.

    1979-01-01

    The role of generative nucleus of Paramecium putrinum in the viability of three clones of different ages and with a normal and small micronucleus (Mi) has been investigated. The Mi was selectively inactivated with a local UV microirradiation at a dose of 3060 erg/mm 2 . Soon after the irradiation, 85% of clone C-6-1 cells (n=60) loose the generative nucleus. In clones K-177 (n=27) and L-2-1 (n=35) the fraction of amicronuclear progeny amounted to 66% and 86% respectively. The progeny of cells that have lost their Mi usually perishes. In some UV-treated cells of clone K-177 the fragmentation of macronucleus was observed; these cells were viable for a long time. It is supposed that fragments of macronucleus can functionally replace the lost or damaged Mi. It is concluded that the generative nucleus of P.putrium is significant for the vegetative life of the celle

  2. Identification and cloning of first cadmium metallothionein like gene from locally isolated ciliate, Paramecium sp.

    Science.gov (United States)

    Shuja, Rukhsana Nighat; Shakoori, Abdul Rauf

    2009-03-01

    First cadmium metallothionein like gene PMCd1 of a ciliate, Paramecium sp., isolated from industrial wastewater has been cloned and sequenced. PMCd1 is an intronless gene, encoding 612 nucleotides, with TAA coding for glutamine. The coding region of PMCd1 comprises 203 amino acids, including 37 cysteine residues with a conserved structural pattern in the form of recurring structural motifs, arranged in 17 x-cys-x-y-cys-x, 1 x-cys-cys-x and x-cys-x contexts. Both, the deduced amino acids and nucleotide sequence differ, not only from other animal metallothioneins (MTs), but also from the previously characterized Tetrahymena Cu and Cd-MTs. The translated protein of PMCd1 contains conserved cysteine residues, peculiar characteristic of stress inducible metallothionein genes of ciliates and other groups of organisms.

  3. Attempts to retreat from a dead-ended long capillary by backward swimming in Paramecium

    Directory of Open Access Journals (Sweden)

    Itsuki eKunita

    2014-06-01

    Full Text Available We have observed how the ciliate Paramecium attempts to retreat from the dead-end of a long capillary that is too narrow for turning. After many trial-and-error episodes of short-term backward swimming (SBS, which is the conventional avoidance behavior exhibited in free swimming when an obstacle is faced, long-term backward swimming (LBS that lasted five to ten times longer was developed. LBS may have a beneficial effect for complete withdrawal from the capillary space, although in our experiment it was impossible for the organism to do so due to the capillary length. In order to identify a physically possible mechanism for LBS, we propose model equations for the membrane potential of Hodgkin-Huxley type, which describe the control of ciliary movement. The physiological implications and physical mechanism of the development of LBS are discussed.

  4. Temporal variation in temperature determines disease spread and maintenance in Paramecium microcosm populations

    Science.gov (United States)

    Duncan, Alison B.; Fellous, Simon; Kaltz, Oliver

    2011-01-01

    The environment is rarely constant and organisms are exposed to temporal and spatial variations that impact their life histories and inter-species interactions. It is important to understand how such variations affect epidemiological dynamics in host–parasite systems. We explored effects of temporal variation in temperature on experimental microcosm populations of the ciliate Paramecium caudatum and its bacterial parasite Holospora undulata. Infected and uninfected populations of two P. caudatum genotypes were created and four constant temperature treatments (26°C, 28°C, 30°C and 32°C) compared with four variable treatments with the same mean temperatures. Variable temperature treatments were achieved by alternating populations between permissive (23°C) and restrictive (35°C) conditions daily over 30 days. Variable conditions and high temperatures caused greater declines in Paramecium populations, greater fluctuations in population size and higher incidence of extinction. The additional effect of parasite infection was additive and enhanced the negative effects of the variable environment and higher temperatures by up to 50 per cent. The variable environment and high temperatures also caused a decrease in parasite prevalence (up to 40%) and an increase in extinction (absence of detection) (up to 30%). The host genotypes responded similarly to the different environmental stresses and their effect on parasite traits were generally in the same direction. This work provides, to our knowledge, the first experimental demonstration that epidemiological dynamics are influenced by environmental variation. We also emphasize the need to consider environmental variance, as well as means, when trying to understand, or predict population dynamics or range. PMID:21450730

  5. Paramecium swimming and ciliary beating patterns: a study on four RNA interference mutations.

    Science.gov (United States)

    Funfak, Anette; Fisch, Cathy; Abdel Motaal, Hatem T; Diener, Julien; Combettes, Laurent; Baroud, Charles N; Dupuis-Williams, Pascale

    2015-01-01

    Paramecium cells swim and feed by beating their thousands of cilia in coordinated patterns. The organization of these patterns and its relationship with cell motility has been the subject of a large body of work, particularly as a model for ciliary beating in human organs where similar organization is seen. However the rapid motion of the cells makes quantitative measurements very challenging. Here we provide detailed measurements of the swimming of Paramecium cells from high-speed video at high magnification, as they move in microfluidic channels. An image analysis protocol allows us to decouple the cell movement from the motion of the cilia, thus allowing us to measure the ciliary beat frequency (CBF) and the spatio-temporal organization into metachronal waves along the cell periphery. Two distinct values of the CBF appear at different regions of the cell: most of the cilia beat in the range of 15 to 45 Hz, while the cilia in the peristomal region beat at almost double the frequency. The body and peristomal CBF display a nearly linear relation with the swimming velocity. Moreover the measurements do not display a measurable correlation between the swimming velocity and the metachronal wave velocity on the cell periphery. These measurements are repeated for four RNAi silenced mutants, where proteins specific to the cilia or to their connection to the cell base are depleted. We find that the mutants whose ciliary structure is affected display similar swimming to the control cells albeit with a reduced efficiency, while the mutations that affect the cilia's anchoring to the cell lead to strongly reduced ability to swim. This reduction in motility can be related to a loss of coordination between the ciliary beating in different parts of the cell.

  6. Mendelian and non-mendelian mutations affecting surface antigen expression in Paramecium tetraurelia

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, L.M.; Forney, J.D.

    1984-08-01

    A screening procedure was devised for the isolation of X-ray-induced mutations affecting the expression of the A immobilization antigen (i-antigen) in Paramecium tetraurelia. Two of the mutations isolated by this procedure proved to be in modifier genes. The two genes are unlinked to each other and unlinked to the structural A i-antigen gene. These are the first modifier genes identified in a Paramecium sp. that affect surface antigen expression. Another mutation was found to be a deletion of sequences just downstream from the A i-antigen gene. In cells carrying this mutation, the A i-antigen gene lies in close proximity to the end of a macronuclear chromosome. The expression of the A i-antigen is not affected in these cells, demonstrating that downstream sequences are not important for the regulation and expression of the A i-antigen gene. A stable cell line was also recovered which shows non-Mendelian inheritance of a macronuclear deletion of the A i-antigen gene. This mutant does not contain the gene in its macronucleus, but contains a complete copy of the gene in its micronucleus. In the cytoplasm of wild-type animals, the micronuclear gene is included in the developing macronucleus; in the cytoplasm of the mutant, the incorporation of the A i-antigen gene into the macronucleus is inhibited. This is the first evidence that a mechanism is available in ciliates to control the expression of a gene by regulating its incorporation into developing macronuclei.

  7. Mendelian and non-mendelian mutations affecting surface antigen expression in Paramecium tetraurelia

    International Nuclear Information System (INIS)

    Epstein, L.M.; Forney, J.D.

    1984-01-01

    A screening procedure was devised for the isolation of X-ray-induced mutations affecting the expression of the A immobilization antigen (i-antigen) in Paramecium tetraurelia. Two of the mutations isolated by this procedure proved to be in modifier genes. The two genes are unlinked to each other and unlinked to the structural A i-antigen gene. These are the first modifier genes identified in a Paramecium sp. that affect surface antigen expression. Another mutation was found to be a deletion of sequences just downstream from the A i-antigen gene. In cells carrying this mutation, the A i-antigen gene lies in close proximity to the end of a macronuclear chromosome. The expression of the A i-antigen is not affected in these cells, demonstrating that downstream sequences are not important for the regulation and expression of the A i-antigen gene. A stable cell line was also recovered which shows non-Mendelian inheritance of a macronuclear deletion of the A i-antigen gene. This mutant does not contain the gene in its macronucleus, but contains a complete copy of the gene in its micronucleus. In the cytoplasm of wild-type animals, the micronuclear gene is included in the developing macronucleus; in the cytoplasm of the mutant, the incorporation of the A i-antigen gene into the macronucleus is inhibited. This is the first evidence that a mechanism is available in ciliates to control the expression of a gene by regulating its incorporation into developing macronuclei

  8. Novel Insights into the Development and Function of Cilia Using the Advantages of the Paramecium Cell and Its Many Cilia

    Directory of Open Access Journals (Sweden)

    Junji Yano

    2015-07-01

    Full Text Available Paramecium species, especially P. tetraurelia and caudatum, are model organisms for modern research into the form and function of cilia. In this review, we focus on the ciliary ion channels and other transmembrane proteins that control the beat frequency and wave form of the cilium by controlling the signaling within the cilium. We put these discussions in the context of the advantages that Paramecium brings to the understanding of ciliary motility: mutants for genetic dissections of swimming behavior, electrophysiology, structural analysis, abundant cilia for biochemistry and modern proteomics, genomics and molecular biology. We review the connection between behavior and physiology, which allows the cells to broadcast the function of their ciliary channels in real time. We build a case for the important insights and advantages that this model organism continues to bring to the study of cilia.

  9. Effects of very low doses of ionizing radiation on the clonal life-span in Paramecium Tetraurelia

    International Nuclear Information System (INIS)

    Tixador, R.; Richoilley, G.; Monrozies, E.; Planel, H.; Tap, G.

    1981-01-01

    Effects of very low doses of ionizing radiation were investigated on life-span in Paramecium tetraurelia. After autogamy single cell cultures were placed (1) in a control chamber with radiopermeable walls; (2) in a shielding device with 10 cm thick lead walls; (3) in a similar shielding device including a 60 Co source giving a dose of 760 mrad per year at the culture level. Life-spans, expressed in days and in mean total number of fissions measured from autogamy to the death of all sublines, were about of 200 fissions and 55 days in controls. Life-spans of shielded sublines were increased and lower life-spans were observed in both shielded and irradiated sublines. These findings provide new evidence for a biological effect of very low doses of ionizing radiations and show that fission potential of Paramecium tetraurelia can be affected by variations in the background radiation level. (author)

  10. Novel Insights into the Development and Function of Cilia Using the Advantages of the Paramecium Cell and Its Many Cilia

    Science.gov (United States)

    Yano, Junji; Valentine, Megan S.; Van Houten, Judith L.

    2015-01-01

    Paramecium species, especially P. tetraurelia and caudatum, are model organisms for modern research into the form and function of cilia. In this review, we focus on the ciliary ion channels and other transmembrane proteins that control the beat frequency and wave form of the cilium by controlling the signaling within the cilium. We put these discussions in the context of the advantages that Paramecium brings to the understanding of ciliary motility: mutants for genetic dissections of swimming behavior, electrophysiology, structural analysis, abundant cilia for biochemistry and modern proteomics, genomics and molecular biology. We review the connection between behavior and physiology, which allows the cells to broadcast the function of their ciliary channels in real time. We build a case for the important insights and advantages that this model organism continues to bring to the study of cilia. PMID:26230712

  11. Macro algae as substrate for biogas production

    DEFF Research Database (Denmark)

    Møller, Henrik; Sarker, Shiplu; Gautam, Dhan Prasad

    Algae as a substrate for biogas is superior to other crops since it has a much higher yield of biomass per unit area and since algae grows in the seawater there will be no competition with food production on agricultural lands. So far, the progress in treating different groups of algae as a source...... of energy is promising. In this study 5 different algae types were tested for biogas potential and two algae were subsequent used for co-digestion with manure. Green seaweed, Ulva lactuca and brown seaweed Laminaria digitata was co-digested with cattle manure at mesophilic and thermophilic condition...

  12. Cross-study analysis of genomic data defines the ciliate multigenic epiplasmin family: strategies for functional analysis in Paramecium tetraurelia

    Directory of Open Access Journals (Sweden)

    Ravet Viviane

    2009-06-01

    Full Text Available Abstract Background The sub-membranous skeleton of the ciliate Paramecium, the epiplasm, is composed of hundreds of epiplasmic scales centered on basal bodies, and presents a complex set of proteins, epiplasmins, which belong to a multigenic family. The repeated duplications observed in the P. tetraurelia genome present an interesting model of the organization and evolution of a multigenic family within a single cell. Results To study this multigenic family, we used phylogenetic, structural, and analytical transcriptional approaches. The phylogenetic method defines 5 groups of epiplasmins in the multigenic family. A refined analysis by Hydrophobic Cluster Analysis (HCA identifies structural characteristics of 51 epiplasmins, defining five separate groups, and three classes. Depending on the sequential arrangement of their structural domains, the epiplasmins are defined as symmetric, asymmetric or atypical. The EST data aid in this classification, in the identification of putative regulating sequences such as TATA or CAAT boxes. When specific RNAi experiments were conducted using sequences from either symmetric or asymmetric classes, phenotypes were drastic. Local effects show either disrupted or ill-shaped epiplasmic scales. In either case, this results in aborted cell division. Using structural features, we show that 4 epiplasmins are also present in another ciliate, Tetrahymena thermophila. Their affiliation with the distinctive structural groups of Paramecium epiplasmins demonstrates an interspecific multigenic family. Conclusion The epiplasmin multigenic family illustrates the history of genomic duplication in Paramecium. This study provides a framework which can guide functional analysis of epiplasmins, the major components of the membrane skeleton in ciliates. We show that this set of proteins handles an important developmental information in Paramecium since maintenance of epiplasm organization is crucial for cell morphogenesis.

  13. 808-nm laser therapy with a flat-top handpiece photobiomodulates mitochondria activities of Paramecium primaurelia (Protozoa).

    Science.gov (United States)

    Amaroli, Andrea; Ravera, Silvia; Parker, Steven; Panfoli, Isabella; Benedicenti, Alberico; Benedicenti, Stefano

    2016-05-01

    Photobiomodulation is proposed as a non-linear process, and only low-level laser therapy (LLLT) is assumed to stimulate exposed cells, whereas high powered laser and fluences can cause negative effects, exhausting the cell's energy reserve as a consequence of excessive photon-based stimulation. In our work, we investigated and compared the effects of 808-nm diode laser (CW) with a new flat-top handpiece. To this purpose, we tested the photobiomodulation effects of 1 and 3 J/cm(2) fluence, both generated by 100 mW or 1 W of laser power and of 64 J/cm(2) of fluence generated by 100 mW, 1 W, 1.5 W or 2 W, as expressed through oxygen consumption and ATP synthesis of Paramecium. Data collected indicates the incremental consumption of oxygen through irradiation with 3 J/cm(2)-100 mW or 64 J/cm(2)-1 W correlates with an increase in Paramecium ATP synthesis. The Paramecium respiration was inhibited by fluences 64 J/cm(2)-100 mW or 64 J/cm(2)-2 W and was followed by a decrease in the endogenous ATP concentration. The 1 J/cm(2)-100 mW or 1 W and 3 J/cm(2)-1 W did not affect mitochondrial activity. The results show that the fluence of 64 J/cm(2)-1 W more than the 3 J/cm(2)-100 mW causes greater efficiency in Paramecium mitochondria respiratory chain activity. Our results suggest that thanks to flat-top handpiece we used, high fluences by high-powered laser have to be reconsidered as an effective and non-invasive therapy. Possible associated benefits of deeper tissue penetration would increase treatment effectiveness and reduced irradiation time.

  14. Influence on cell proliferation of background radiation or exposure to very low, chronic gamma radiation. [Paramecium tetraurelia; Synechococcus lividus

    Energy Technology Data Exchange (ETDEWEB)

    Planel, H.; Soleilhavoup, J.P.; Tixador, R.; Richoilley, G.; Conter, A.; Croute, F.; Caratero, C.; Gaubin, Y.

    1987-05-01

    Investigations carried out on the protozoan Paramecium tetraurelia and the cyanobacteria Synechococcus lividus, which were shielded against background radiation or exposed to very low doses of gamma radiation, demonstrated that radiation can stimulate the proliferation of these two single-cell organisms. Radiation hormesis depends on internal factors (age of starting cells) and external factors (lighting conditions). The stimulatory effect occurred only in a limited range of doses and disappeared for dose rates higher than 50 mGy/y.

  15. Cross-study analysis of genomic data defines the ciliate multigenic epiplasmin family: strategies for functional analysis in Paramecium tetraurelia.

    Science.gov (United States)

    Damaj, Raghida; Pomel, Sébastien; Bricheux, Geneviève; Coffe, Gérard; Viguès, Bernard; Ravet, Viviane; Bouchard, Philippe

    2009-06-03

    The sub-membranous skeleton of the ciliate Paramecium, the epiplasm, is composed of hundreds of epiplasmic scales centered on basal bodies, and presents a complex set of proteins, epiplasmins, which belong to a multigenic family. The repeated duplications observed in the P. tetraurelia genome present an interesting model of the organization and evolution of a multigenic family within a single cell. To study this multigenic family, we used phylogenetic, structural, and analytical transcriptional approaches. The phylogenetic method defines 5 groups of epiplasmins in the multigenic family. A refined analysis by Hydrophobic Cluster Analysis (HCA) identifies structural characteristics of 51 epiplasmins, defining five separate groups, and three classes. Depending on the sequential arrangement of their structural domains, the epiplasmins are defined as symmetric, asymmetric or atypical. The EST data aid in this classification, in the identification of putative regulating sequences such as TATA or CAAT boxes. When specific RNAi experiments were conducted using sequences from either symmetric or asymmetric classes, phenotypes were drastic. Local effects show either disrupted or ill-shaped epiplasmic scales. In either case, this results in aborted cell division. Using structural features, we show that 4 epiplasmins are also present in another ciliate, Tetrahymena thermophila. Their affiliation with the distinctive structural groups of Paramecium epiplasmins demonstrates an interspecific multigenic family. The epiplasmin multigenic family illustrates the history of genomic duplication in Paramecium. This study provides a framework which can guide functional analysis of epiplasmins, the major components of the membrane skeleton in ciliates. We show that this set of proteins handles an important developmental information in Paramecium since maintenance of epiplasm organization is crucial for cell morphogenesis.

  16. Transposon Invasion of the Paramecium Germline Genome Countered by a Domesticated PiggyBac Transposase and the NHEJ Pathway

    Science.gov (United States)

    Dubois, Emeline; Bischerour, Julien; Marmignon, Antoine; Mathy, Nathalie; Régnier, Vinciane; Bétermier, Mireille

    2012-01-01

    Sequences related to transposons constitute a large fraction of extant genomes, but insertions within coding sequences have generally not been tolerated during evolution. Thanks to their unique nuclear dimorphism and to their original mechanism of programmed DNA elimination from their somatic nucleus (macronucleus), ciliates are emerging model organisms for the study of the impact of transposable elements on genomes. The germline genome of the ciliate Paramecium, located in its micronucleus, contains thousands of short intervening sequences, the IESs, which interrupt 47% of genes. Recent data provided support to the hypothesis that an evolutionary link exists between Paramecium IESs and Tc1/mariner transposons. During development of the macronucleus, IESs are excised precisely thanks to the coordinated action of PiggyMac, a domesticated piggyBac transposase, and of the NHEJ double-strand break repair pathway. A PiggyMac homolog is also required for developmentally programmed DNA elimination in another ciliate, Tetrahymena. Here, we present an overview of the life cycle of these unicellular eukaryotes and of the developmentally programmed genome rearrangements that take place at each sexual cycle. We discuss how ancient domestication of a piggyBac transposase might have allowed Tc1/mariner elements to spread throughout the germline genome of Paramecium, without strong counterselection against insertion within genes. PMID:22888464

  17. Different polyamine pathways from bacteria have replaced eukaryotic spermidine biosynthesis in ciliates Tetrahymena thermophila and Paramecium tetaurelia.

    Science.gov (United States)

    Li, Bin; Kim, Sok Ho; Zhang, Yang; Hanfrey, Colin C; Elliott, Katherine A; Ealick, Steven E; Michael, Anthony J

    2015-09-01

    The polyamine spermidine is absolutely required for growth and cell proliferation in eukaryotes, due to its role in post-translational modification of essential translation elongation factor eIF5A, mediated by deoxyhypusine synthase. We have found that free-living ciliates Tetrahymena and Paramecium lost the eukaryotic genes encoding spermidine biosynthesis: S-adenosylmethionine decarboxylase (AdoMetDC) and spermidine synthase (SpdSyn). In Tetrahymena, they were replaced by a gene encoding a fusion protein of bacterial AdoMetDC and SpdSyn, present as three copies. In Paramecium, a bacterial homospermidine synthase replaced the eukaryotic genes. Individual AdoMetDC-SpdSyn fusion protein paralogues from Tetrahymena exhibit undetectable AdoMetDC activity; however, when two paralogous fusion proteins are mixed, AdoMetDC activity is restored and spermidine is synthesized. Structural modelling indicates a functional active site is reconstituted by sharing critical residues from two defective protomers across the heteromer interface. Paramecium was found to accumulate homospermidine, suggesting it replaces spermidine for growth. To test this concept, a budding yeast spermidine auxotrophic strain was found to grow almost normally with homospermidine instead of spermidine. Biosynthesis of spermidine analogue aminopropylcadaverine, but not exogenously provided norspermidine, correlated with some growth. Finally, we found that diverse single-celled eukaryotic parasites and multicellular metazoan Schistosoma worms have lost the spermidine biosynthetic pathway but retain deoxyhypusine synthase. © 2015 John Wiley & Sons Ltd.

  18. Calcium signaling in closely related protozoan groups (Alveolata): non-parasitic ciliates (Paramecium, Tetrahymena) vs. parasitic Apicomplexa (Plasmodium, Toxoplasma).

    Science.gov (United States)

    Plattner, H; Sehring, I M; Mohamed, I K; Miranda, K; De Souza, W; Billington, R; Genazzani, A; Ladenburger, E-M

    2012-05-01

    The importance of Ca2+-signaling for many subcellular processes is well established in higher eukaryotes, whereas information about protozoa is restricted. Recent genome analyses have stimulated such work also with Alveolates, such as ciliates (Paramecium, Tetrahymena) and their pathogenic close relatives, the Apicomplexa (Plasmodium, Toxoplasma). Here we compare Ca2+ signaling in the two closely related groups. Acidic Ca2+ stores have been characterized in detail in Apicomplexa, but hardly in ciliates. Two-pore channels engaged in Ca2+-release from acidic stores in higher eukaryotes have not been stingently characterized in either group. Both groups are endowed with plasma membrane- and endoplasmic reticulum-type Ca2+-ATPases (PMCA, SERCA), respectively. Only recently was it possible to identify in Paramecium a number of homologs of ryanodine and inositol 1,3,4-trisphosphate receptors (RyR, IP3R) and to localize them to widely different organelles participating in vesicle trafficking. For Apicomplexa, physiological experiments suggest the presence of related channels although their identity remains elusive. In Paramecium, IP3Rs are constitutively active in the contractile vacuole complex; RyR-related channels in alveolar sacs are activated during exocytosis stimulation, whereas in the parasites the homologous structure (inner membrane complex) may no longer function as a Ca2+ store. Scrutinized comparison of the two closely related protozoan phyla may stimulate further work and elucidate adaptation to parasitic life. See also "Conclusions" section. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Revised systematics of Holospora-like bacteria and characterization of "Candidatus Gortzia infectiva", a novel macronuclear symbiont of Paramecium jenningsi.

    Science.gov (United States)

    Boscaro, Vittorio; Fokin, Sergei I; Schrallhammer, Martina; Schweikert, Michael; Petroni, Giulio

    2013-01-01

    The genus Holospora (Rickettsiales) includes highly infectious nuclear symbionts of the ciliate Paramecium with unique morphology and life cycle. To date, nine species have been described, but a molecular characterization is lacking for most of them. In this study, we have characterized a novel Holospora-like bacterium (HLB) living in the macronuclei of a Paramecium jenningsi population. This bacterium was morphologically and ultrastructurally investigated in detail, and its life cycle and infection capabilities were described. We also obtained its 16S rRNA gene sequence and developed a specific probe for fluorescence in situ hybridization experiments. A new taxon, "Candidatus Gortzia infectiva", was established for this HLB according to its unique characteristics and the relatively low DNA sequence similarities shared with other bacteria. The phylogeny of the order Rickettsiales based on 16S rRNA gene sequences has been inferred, adding to the available data the sequence of the novel bacterium and those of two Holospora species (Holospora obtusa and Holospora undulata) characterized for the purpose. Our phylogenetic analysis provided molecular support for the monophyly of HLBs and showed a possible pattern of evolution for some of their features. We suggested to classify inside the family Holosporaceae only HLBs, excluding other more distantly related and phenotypically different Paramecium endosymbionts.

  20. Transposon Invasion of the Paramecium Germline Genome Countered by a Domesticated PiggyBac Transposase and the NHEJ Pathway

    Directory of Open Access Journals (Sweden)

    Emeline Dubois

    2012-01-01

    Full Text Available Sequences related to transposons constitute a large fraction of extant genomes, but insertions within coding sequences have generally not been tolerated during evolution. Thanks to their unique nuclear dimorphism and to their original mechanism of programmed DNA elimination from their somatic nucleus (macronucleus, ciliates are emerging model organisms for the study of the impact of transposable elements on genomes. The germline genome of the ciliate Paramecium, located in its micronucleus, contains thousands of short intervening sequences, the IESs, which interrupt 47% of genes. Recent data provided support to the hypothesis that an evolutionary link exists between Paramecium IESs and Tc1/mariner transposons. During development of the macronucleus, IESs are excised precisely thanks to the coordinated action of PiggyMac, a domesticated piggyBac transposase, and of the NHEJ double-strand break repair pathway. A PiggyMac homolog is also required for developmentally programmed DNA elimination in another ciliate, Tetrahymena. Here, we present an overview of the life cycle of these unicellular eukaryotes and of the developmentally programmed genome rearrangements that take place at each sexual cycle. We discuss how ancient domestication of a piggyBac transposase might have allowed Tc1/mariner elements to spread throughout the germline genome of Paramecium, without strong counterselection against insertion within genes.

  1. The membrane skeleton in Paramecium: Molecular characterization of a novel epiplasmin family and preliminary GFP expression results.

    Science.gov (United States)

    Pomel, Sébastien; Diogon, Marie; Bouchard, Philippe; Pradel, Lydie; Ravet, Viviane; Coffe, Gérard; Viguès, Bernard

    2006-02-01

    Previous attempts to identify the membrane skeleton of Paramecium cells have revealed a protein pattern that is both complex and specific. The most prominent structural elements, epiplasmic scales, are centered around ciliary units and are closely apposed to the cytoplasmic side of the inner alveolar membrane. We sought to characterize epiplasmic scale proteins (epiplasmins) at the molecular level. PCR approaches enabled the cloning and sequencing of two closely related genes by amplifications of sequences from a macronuclear genomic library. Using these two genes (EPI-1 and EPI-2), we have contributed to the annotation of the Paramecium tetraurelia macronuclear genome and identified 39 additional (paralogous) sequences. Two orthologous sequences were found in the Tetrahymena thermophila genome. Structural analysis of the 43 sequences indicates that the hallmark of this new multigenic family is a 79 aa domain flanked by two Q-, P- and V-rich stretches of sequence that are much more variable in amino-acid composition. Such features clearly distinguish members of the multigenic family from epiplasmic proteins previously sequenced in other ciliates. The expression of Green Fluorescent Protein (GFP)-tagged epiplasmin showed significant labeling of epiplasmic scales as well as oral structures. We expect that the GFP construct described herein will prove to be a useful tool for comparative subcellular localization of different putative epiplasmins in Paramecium.

  2. Synthetic polyester from algae oil.

    Science.gov (United States)

    Roesle, Philipp; Stempfle, Florian; Hess, Sandra K; Zimmerer, Julia; Río Bártulos, Carolina; Lepetit, Bernard; Eckert, Angelika; Kroth, Peter G; Mecking, Stefan

    2014-06-23

    Current efforts to technically use microalgae focus on the generation of fuels with a molecular structure identical to crude oil based products. Here we suggest a different approach for the utilization of algae by translating the unique molecular structures of algae oil fatty acids into higher value chemical intermediates and materials. A crude extract from a microalga, the diatom Phaeodactylum tricornutum, was obtained as a multicomponent mixture containing amongst others unsaturated fatty acid (16:1, 18:1, and 20:5) phosphocholine triglycerides. Exposure of this crude algae oil to CO and methanol with the known catalyst precursor [{1,2-(tBu2 PCH2)2C6H4}Pd(OTf)](OTf) resulted in isomerization/methoxycarbonylation of the unsaturated fatty acids into a mixture of linear 1,17- and 1,19-diesters in high purity (>99 %). Polycondensation with a mixture of the corresponding diols yielded a novel mixed polyester-17/19.17/19 with an advantageously high melting and crystallization temperature. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Growing swimming algae for bioenergy

    Science.gov (United States)

    Croze, Ottavio

    Biofuel production from photosynthetic microalgae is not commercially viable due to high processing costs. New engineering and biological solutions are being sought to reduce these costs by increasing processing efficiency (productivity per energy input). Important physics, however, is ignored. For example, the fluid dynamics of algal suspensions in photobioreactors (ponds or tube arrays) is non-trivial, particularly if the algae swim. Cell reorientation by passive viscous and gravitational torques (gyrotaxis) or active reorientation by light (phototaxis) cause swimming algae in suspension to structure in flows, even turbulent ones. This impacts the distribution and dispersion of swimmers, with significant consequences for photobioreactor operation and design. In this talk, I will describe a theory that predicts swimmer dispersion in laminar pipe flows. I will then then present experimental tests of the theory, as well as new results on the circadian suspension dynamics of the algaChlamydomonas reinhardtii in lab-scale photobioreactors. Finally, I will briefly consider the implications of our work, and related active matter research, for improving algal bioprocessing efficiency. Winton Programme for the Physics of Sustainability.

  4. Parasites in algae mass culture

    Directory of Open Access Journals (Sweden)

    Todd William Lane

    2014-06-01

    Full Text Available Parasites are now known to be ubiquitous across biological systems and can play an important role in modulating algal populations. However, there is a lack of extensive information on their role in artificial ecosystems such as algal production ponds and photobioreactors. Parasites have been implicated in the demise of algal blooms. Because individual mass culture systems often tend to be unialgal and a select few algal species are in wide scale application, there is an increased potential for parasites to have a devastating effect on commercial scale monoculture. As commercial algal production continues to expand with a widening variety of applications, including biofuel, food and pharmaceuticals, the parasites associated with algae will become of greater interest and potential economic impact. A number of important algal parasites have been identified in algal mass culture systems in the last few years and this number is sure to grow as the number of commercial algae ventures increases. Here, we review the research that has identified and characterized parasites infecting mass cultivated algae, the techniques being proposed and or developed to control them, and the potential impact of parasites on the future of the algal biomass industry.

  5. Bioethanol Production from Indigenous Algae

    Directory of Open Access Journals (Sweden)

    Madhuka Roy

    2015-02-01

    Full Text Available Enhanced rate of fossil fuel extraction is likely to deplete limited natural resources over short period of time. So search for alternative fuel is only the way to overcome this problem of upcoming energy crisis. In this aspect biofuel is a sustainable option. Agricultural lands cannot be compromised for biofuel production due to the requirement of food for the increasing population. Certain species of algae can produce ethanol during anaerobic fermentation and thus serve as a direct source for bioethanol production. The high content of complex carbohydrates entrapped in the cell wall of the microalgae makes it essential to incorporate a pre-treatment stage to release and convert these complex carbohydrates into simple sugars prior to the fermentation process. There have been researches on production of bioethanol from a particular species of algae, but this work was an attempt to produce bioethanol from easily available indigenous algae. Acid hydrolysis was carried out as pre-treatment. Gas Chromatographic analysis showed that 5 days’ fermentation by baker’s yeast had yielded 93% pure bioethanol. The fuel characterization of the bioethanol with respect to gasoline showed comparable and quite satisfactory results for its use as an alternative fuel.DOI: http://dx.doi.org/10.3126/ije.v4i1.12182International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15, page: 112-120  

  6. Sampling strategies for improving tree accuracy and phylogenetic analyses: a case study in ciliate protists, with notes on the genus Paramecium.

    Science.gov (United States)

    Yi, Zhenzhen; Strüder-Kypke, Michaela; Hu, Xiaozhong; Lin, Xiaofeng; Song, Weibo

    2014-02-01

    In order to assess how dataset-selection for multi-gene analyses affects the accuracy of inferred phylogenetic trees in ciliates, we chose five genes and the genus Paramecium, one of the most widely used model protist genera, and compared tree topologies of the single- and multi-gene analyses. Our empirical study shows that: (1) Using multiple genes improves phylogenetic accuracy, even when their one-gene topologies are in conflict with each other. (2) The impact of missing data on phylogenetic accuracy is ambiguous: resolution power and topological similarity, but not number of represented taxa, are the most important criteria of a dataset for inclusion in concatenated analyses. (3) As an example, we tested the three classification models of the genus Paramecium with a multi-gene based approach, and only the monophyly of the subgenus Paramecium is supported. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Bacterial Enhancement of Vinyl Fouling by Algae

    OpenAIRE

    Holmes, Paul E.

    1986-01-01

    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 Phormidiu...

  8. Antioxidant Activity of Hawaiian Marine Algae

    OpenAIRE

    Kelman, Dovi; Posner, Ellen Kromkowski; McDermid, Karla J.; Tabandera, Nicole K.; Wright, Patrick R.; Wright, Anthony D.

    2012-01-01

    Marine algae are known to contain a wide variety of bioactive compounds, many of which have commercial applications in pharmaceutical, medical, cosmetic, nutraceutical, food and agricultural industries. Natural antioxidants, found in many algae, are important bioactive compounds that play an important role against various diseases and ageing processes through protection of cells from oxidative damage. In this respect, relatively little is known about the bioactivity of Hawaiian algae that cou...

  9. Stochastic Forecasting of Algae Blooms in Lakes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peng; Tartakovsky, Daniel M.; Tartakovsky, Alexandre M.

    2013-01-15

    We consider the development of harmful algae blooms (HABs) in a lake with uncertain nutrients inflow. Two general frameworks, Fokker-Planck equation and the PDF methods, are developed to quantify the resultant concentration uncertainty of various algae groups, via deriving a deterministic equation of their joint probability density function (PDF). A computational example is examined to study the evolution of cyanobacteria (the blue-green algae) and the impacts of initial concentration and inflow-outflow ratio.

  10. Otimização do cultivo do Paramecium caudatum para estudo em testes de toxicidade.

    Directory of Open Access Journals (Sweden)

    Manoel Messias Pereira Miranda

    2013-04-01

    Full Text Available A deposição contínua de diversos poluentes no ambiente é uma preocupação cada vez maior devido aos potenciais efeitos, diretos ou indiretos, na ecologia dos ambientes e na saúde humana. Dentre os poluentes, os metais podem atingir concentrações nas quais podem ser altamente tóxicos para a biota local e, eventualmente, acumulados nos tecidos e transferidos pela cadeia trófica. Em baixas concentrações, que são denominados elementos-traço, ou micro nutrientes; dessa forma alguns metais são essenciais para o metabolismo celular ao exercerem diversos papéis como, por exemplo: co-fatores enzimáticos, ligantes ou precursores de moléculas vitais ou ainda participar da regulação enzimática. Na biota aquática, os protozoários são organismos unicelulares eucarióticos que estão no início da cadeia trófica e que são modelos apropriados para prever os efeitos de substâncias químicas em vários organismos presentes nesse ambiente. Eles têm sido utilizados em estudos toxicológicos e propostos como organismos teste para avaliar contaminações em meio aquático, devido à grande sensibilidade a alterações ambientais, ao curto ciclo de vida e pela facilidade de cultivo. No presente trabalho o protozoário ciliado Paramecium caudatum Ehrenberg, 1833 foi isolado da Represa do Monjolinho (São Carlos-SP e mantido em cultura monoxênica. Foi verificado previamente, por meio de experimentos, que essa linhagem de Paramecium caudatum apresenta condição ótima de cultivo no escuro, em pH 8 e temperatura de 30ºC. Nessas mesmas condições foi feita uma curva de crescimento a partir da qual foi determinado seu tempo de geração (5,3 horas e a fase log (logarítmica de crescimento.

  11. Paramecium BBS genes are key to presence of channels in Cilia

    Directory of Open Access Journals (Sweden)

    Valentine Megan

    2012-09-01

    Full Text Available Abstract Background Changes in genes coding for ciliary proteins contribute to complex human syndromes called ciliopathies, such as Bardet-Biedl Syndrome (BBS. We used the model organism Paramecium to focus on ciliary ion channels that affect the beat form and sensory function of motile cilia and evaluate the effects of perturbing BBS proteins on these channels. Methods We used immunoprecipitations and mass spectrometry to explore whether Paramecium proteins interact as in mammalian cells. We used RNA interference (RNAi and swimming behavior assays to examine the effects of BBS depletion on ciliary ion channels that control ciliary beating. Combining RNA interference and epitope tagging, we examined the effects of BBS depletion of BBS 7, 8 and 9 on the location of three channels and a chemoreceptor in cilia. Results We found 10 orthologs of 8 BBS genes in P. tetraurelia. BBS1, 2, 4, 5, 7, 8 and 9 co-immunoprecipitate. While RNAi reduction of BBS 7 and 9 gene products caused loss and shortening of cilia, RNAi for all BBS genes except BBS2 affected patterns of ciliary motility that are governed by ciliary ion channels. Swimming behavior assays pointed to loss of ciliary K+ channel function. Combining RNAi and epitope tagged ciliary proteins we demonstrated that a calcium activated K+ channel was no longer located in the cilia upon depletion of BBS 7, 8 or 9, consistent with the cells’ swimming behavior. The TRPP channel PKD2 was also lost from the cilia. In contrast, the ciliary voltage gated calcium channel was unaffected by BBS depletion, consistent with behavioral assays. The ciliary location of a chemoreceptor for folate was similarly unperturbed by the depletion of BBS 7, 8 or 9. Conclusions The co-immunoprecipitation of BBS 1,2,4,5,7,8, and 9 suggests a complex of BBS proteins. RNAi for BBS 7, 8 or 9 gene products causes the selective loss of K+ and PKD2 channels from the cilia while the critical voltage gated calcium channel and a

  12. Use of a novel cell adhesion method and digital measurement to show stimulus-dependent variation in somatic and oral ciliary beat frequency in Paramecium.

    Science.gov (United States)

    Bell, Wade E; Hallworth, Richard; Wyatt, Todd A; Sisson, Joseph H

    2015-01-01

    When Paramecium encounters positive stimuli, the membrane hyperpolarizes and ciliary beat frequency increases. We adapted an established immobilization protocol using a biological adhesive and a novel digital analysis system to quantify beat frequency in immobilized Paramecium. Cells showed low mortality and demonstrated beat frequencies consistent with previous studies. Chemoattractant molecules, reduction in external potassium, and posterior stimulation all increased somatic beat frequency. In all cases, the oral groove cilia maintained a higher beat frequency than mid-body cilia, but only oral cilia from cells stimulated with chemoattactants showed an increase from basal levels. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

  13. Paramecium tetraurelia growth stimulation under low-level chronic irradiation: investigations on a possible mechanism

    International Nuclear Information System (INIS)

    Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H.

    1982-01-01

    Experiments were carried out to demonstrate the effects of low-level chronic irradiation on Paramecium tetraurelia proliferation. Biological effects were strongly dependent on the bacterial density of culture medium and more exactly on the catalase content of the medium. Significant growth stimulation was found under 60 Co chronic irradiation at a dose rate of 2 rad/year when paramecia were grown in a medium containing a high bacterial concentration (2.5 x 10 2 cells/m) or supplemented with catalase (300 U/ml). In a medium with a low bacterial density (1 x 10 6 cell/ml) or supplemented with a catalase activity inhibitor, growth simulation was preceded by a transitory inhibiting effect which could be correlated with extracellularly radioproduced H 2 O 2 . H 2 O 2 addition appeared to be able to simulate the biological effects of chronic irradiation. A possible mechanism is discussed.We proposed that the stimulating effects were the result of intracellular enzymatic scavenging of radioproduced H 2 O 2

  14. Timing of Developmentally Programmed Excision and Circularization of Paramecium Internal Eliminated Sequences

    Science.gov (United States)

    Bétermier, Mireille; Duharcourt, Sandra; Seitz, Hervé; Meyer, Eric

    2000-01-01

    Paramecium internal eliminated sequences (IESs) are short AT-rich DNA elements that are precisely eliminated from the germ line genome during development of the somatic macronucleus. They are flanked by one 5′-TA-3′ dinucleotide on each side, a single copy of which remains at the donor site after excision. The timing of their excision was examined in synchronized conjugating cells by quantitative PCR. Significant amplification of the germ line genome was observed prior to IES excision, which starts 12 to 14 h after initiation of conjugation and extends over a 2- to 4-h period. Following excision, two IESs were shown to form extrachromosomal circles that can be readily detected on Southern blots of genomic DNA from cells undergoing macronuclear development. On these circular molecules, covalently joined IES ends are separated by one copy of the flanking 5′-TA-3′ repeat. The similar structures of the junctions formed on the excised and donor molecules point to a central role for this dinucleotide in IES excision. PMID:10669733

  15. Growth retardation of paramecium and mouse cells by shielding them from background radiation

    International Nuclear Information System (INIS)

    Kawanishi, Masanobu; Okuyama, Katsuyuki; Shiraishi, Kazunori; Matsuda, Yatsuka; Taniguchi, Ryoichi; Shiomi, Nobuyuki; Yonezawa, Morio; Yagi, Takashi

    2012-01-01

    In the 1970s and 1980s, Planel et al. reported that the growth of paramecia was decreased by shielding them from background radiation. In the 1990s, Takizawa et al. found that mouse cells displayed a decreased growth rate under shielded conditions. The purpose of the present study was to confirm that growth is impaired in organisms that have been shielded from background radiation. Radioprotection was produced with a shielding chamber surrounded by a 15 cm thick iron wall and a 10 cm thick paraffin wall that reduced the γ ray and neutron levels in the chamber to 2% and 25% of the background levels, respectively. Although the growth of Paramecium tetraurelia was not impaired by short-term radioprotection (around 10 days), which disagreed with the findings of Planel et al., decreased growth was observed after long-term (40-50 days) radiation shielding. When mouse lymphoma L5178Y cells were incubated inside or outside of the shielding chamber for 7 days, the number of cells present on the 6th and 7th days under the shielding conditions was significantly lower than that present under the non-shielding conditions. These inhibitory effects on cell growth were abrogated by the addition of a 137 Cs γ-ray source disk to the chamber. Furthermore, no growth retardation was observed in XRCC4-deficient mouse M10 cells, which display impaired DNA double strand break repair. (author)

  16. Host and symbiont intraspecific variability: The case of Paramecium calkinsi and "Candidatus Trichorickettsia mobilis".

    Science.gov (United States)

    Sabaneyeva, E; Castelli, M; Szokoli, F; Benken, K; Lebedeva, N; Salvetti, A; Schweikert, M; Fokin, S; Petroni, G

    2018-02-01

    Newly isolated strains of the ciliate Paramecium calkinsi and their cytoplasmic bacterial endosymbionts were characterized by a multidisciplinary approach, including live observation, ultrastructural investigation, and molecular analysis. Despite morphological resemblance, the characterized P. calkinsi strains showed a significant molecular divergence compared to conspecifics, possibly hinting for a cryptic speciation. The endosymbionts were clearly found to be affiliated to the species "Candidatus Trichorickettsia mobilis" (Rickettsiales, Rickettsiaceae), currently encompassing only bacteria retrieved in an obligate intracellular association with other ciliates. However, a relatively high degree of intraspecific divergence was observed as well, thus it was possible to split "Candidatus Trichorickettsia" into three subspecies, one of which represented so far only by the newly characterized endosymbionts of P. calkinsi. Other features distinguished the members of each different subspecies. In particular, the endosymbionts of P. calkinsi resided in the cytoplasm and possessed numerous peritrichous flagella, although no motility was evidenced, whereas their conspecifics in other hosts were either cytoplasmic and devoid of flagella, or macronuclear, displaying flagellar-driven motility. Moreover, contrarily to previously analyzed "Candidatus Trichorickettsia" hosts, infected P. calkinsi cells frequently became amicronucleate and demonstrated abnormal cell division, eventually leading to decline of the laboratory culture. Copyright © 2017 Elsevier GmbH. All rights reserved.

  17. A Ca2+ influx associated with exocytosis is specifically abolished in a Paramecium exocytotic mutant

    International Nuclear Information System (INIS)

    Kerboeuf, D.; Cohen, J.

    1990-01-01

    A Paramecium possesses secretory organelles called trichocysts which are docked beneath the plasma membrane awaiting an external stimulus that triggers their exocytosis. Membrane fusion is the sole event provoked by the stimulation and can therefore be studied per se. Using 3 microM aminoethyl dextran as a vital secretagogue, we analyzed the movements of calcium (Ca 2+ ) during the discharge of trichocysts. We showed that (a) external Ca 2+ , at least at 3 X 10(-7) M, is necessary for AED to induce exocytosis; (b) a dramatic and transient influx of Ca 2+ as measured from 45 Ca uptake is induced by AED; (c) this influx is independent of the well-characterized voltage-operated Ca 2+ channels of the ciliary membranes since it persists in a mutant devoid of these channels; and (d) this influx is specifically abolished in one of the mutants unable to undergo exocytosis, nd12. We propose that the Ca 2+ influx induced by AED reflects an increase in membrane permeability through the opening of novel Ca 2+ channel or the activation of other Ca 2+ transport mechanism in the plasma membrane. The resulting rise in cytosolic Ca 2+ concentration would in turn induce membrane fusion. The mutation nd12 would affect a gene product involved in the control of plasma membrane permeability to Ca 2+ , specifically related to membrane fusion

  18. Virus-host interactions: insights from the replication cycle of the large Paramecium bursaria chlorella virus.

    Science.gov (United States)

    Milrot, Elad; Mutsafi, Yael; Fridmann-Sirkis, Yael; Shimoni, Eyal; Rechav, Katya; Gurnon, James R; Van Etten, James L; Minsky, Abraham

    2016-01-01

    The increasing interest in cytoplasmic factories generated by eukaryotic-infecting viruses stems from the realization that these highly ordered assemblies may contribute fundamental novel insights to the functional significance of order in cellular biology. Here, we report the formation process and structural features of the cytoplasmic factories of the large dsDNA virus Paramecium bursaria chlorella virus 1 (PBCV-1). By combining diverse imaging techniques, including scanning transmission electron microscopy tomography and focused ion beam technologies, we show that the architecture and mode of formation of PBCV-1 factories are significantly different from those generated by their evolutionary relatives Vaccinia and Mimivirus. Specifically, PBCV-1 factories consist of a network of single membrane bilayers acting as capsid templates in the central region, and viral genomes spread throughout the host cytoplasm but excluded from the membrane-containing sites. In sharp contrast, factories generated by Mimivirus have viral genomes in their core, with membrane biogenesis region located at their periphery. Yet, all viral factories appear to share structural features that are essential for their function. In addition, our studies support the notion that PBCV-1 infection, which was recently reported to result in significant pathological outcomes in humans and mice, proceeds through a bacteriophage-like infection pathway. © 2015 John Wiley & Sons Ltd.

  19. Maintenance of algal endosymbionts in Paramecium bursaria: a simple model based on population dynamics.

    Science.gov (United States)

    Iwai, Sosuke; Fujiwara, Kenji; Tamura, Takuro

    2016-09-01

    Algal endosymbiosis is widely distributed in eukaryotes including many protists and metazoans, and plays important roles in aquatic ecosystems, combining phagotrophy and phototrophy. To maintain a stable symbiotic relationship, endosymbiont population size in the host must be properly regulated and maintained at a constant level; however, the mechanisms underlying the maintenance of algal endosymbionts are still largely unknown. Here we investigate the population dynamics of the unicellular ciliate Paramecium bursaria and its Chlorella-like algal endosymbiont under various experimental conditions in a simple culture system. Our results suggest that endosymbiont population size in P. bursaria was not regulated by active processes such as cell division coupling between the two organisms, or partitioning of the endosymbionts at host cell division. Regardless, endosymbiont population size was eventually adjusted to a nearly constant level once cells were grown with light and nutrients. To explain this apparent regulation of population size, we propose a simple mechanism based on the different growth properties (specifically the nutrient requirements) of the two organisms, and based from this develop a mathematical model to describe the population dynamics of host and endosymbiont. The proposed mechanism and model may provide a basis for understanding the maintenance of algal endosymbionts. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  20. Characterization of four arginine kinases in the ciliate Paramecium tetraurelia: Investigation on the substrate inhibition mechanism.

    Science.gov (United States)

    Yano, Daichi; Suzuki, Takaya; Hirokawa, Saki; Fuke, Kyoko; Suzuki, Tomohiko

    2017-08-01

    The ciliate Paramecium tetraurelia contains four arginine kinase genes (AK1-4). We detected cDNA for only three of the AKs (AK1-3) via PCR. Recombinant AK1-4 were expressed in Escherichia coli and their kinetics parameters determined. AK3 showed typical substrate inhibition toward arginine, and enzymatic activity markedly decreased when arginine concentration increased. This is the first example of substrate inhibition in wild-type phosphagen kinases. To explore the substrate inhibition mechanism, site-directed mutations were generated, targeting the amino acid sequence D-D-S-Q-V at positions 77-81 in P. tetraurelia AK3. Among the mutants, substrate inhibition was lost remarkably in the S79A mutant. In spite of high amino acid sequence identity (91%) between P. tetraurelia AK3 and AK4, the enzymatic activity of AK4 was less by 3% than that of AK3. We noticed that the conservative G298 was unusually replaced by R in P. tetraurelia AK4, and we constructed two mutants, R298G/AK4 and G298R/AK3. Enzymatic activity of the former mutant was comparable with that of the wild-type AK3, whereas that of the latter mutant was dramatically reduced. Thus, we concluded that the significantly low activity of P. tetraurelia AK4 is due to the residue R298. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Peculiarities of near-ultraviolet (365 nm) and visible light effects in Paramecium Caudatum cells

    International Nuclear Information System (INIS)

    Samoilova, K.A.; Sushchenko, N.B.

    1977-01-01

    After treatment with 365 nm or visible light Paramecium caudatum cells fail to divide and die shortly after irradiation; no death occurs long after irradiation, as well as after several cell cycles, unlike the situation after the action of 254 nm or 300-380 nm. Irradiation inhibits mainly the first cell cycle following which the recovery of cells starts. Thus no after-effects take place after the action of 365 nm and visible light, and the patterns of their effects are rather similar. The photoreactivation of damages induced by 365 nm is quite small, being about 2 times less than that for 254 nm and 300-380 nm. Similarity of the action of 254, 300-380, 365 nm and visible light was established by the stimulation of cell division by low doses and increase in viability of infusoria from cultures with low survival and depressed rate of multiplication. This effect of 365 nm is not eliminated by visible light; moreover, the latter promotes the 'therapeutic' effect of the 365 nm line. (author)

  2. Sas-4 proteins are required during basal body duplication in Paramecium

    Science.gov (United States)

    Gogendeau, Delphine; Hurbain, Ilse; Raposo, Graca; Cohen, Jean; Koll, France; Basto, Renata

    2011-01-01

    Centrioles and basal bodies are structurally related organelles composed of nine microtubule (MT) triplets. Studies performed in Caenorhabditis elegans embryos have shown that centriole duplication takes place in sequential way, in which different proteins are recruited in a specific order to assemble a procentriole. ZYG-1 initiates centriole duplication by triggering the recruitment of a complex of SAS-5 and SAS-6, which then recruits the final player, SAS-4, to allow the incorporation of MT singlets. It is thought that a similar mechanism (that also involves additional proteins) is present in other animal cells, but it remains to be investigated whether the same players and their ascribed functions are conserved during basal body duplication in cells that exclusively contain basal bodies. To investigate this question, we have used the multiciliated protist Paramecium tetraurelia. Here we show that in the absence of PtSas4, two types of defects in basal body duplication can be identified. In the majority of cases, the germinative disk and cartwheel, the first structures assembled during duplication, are not detected. In addition, if daughter basal bodies were formed, they invariably had defects in MT recruitment. Our results suggest that PtSas4 has a broader function than its animal orthologues. PMID:21289083

  3. The alteration of Paramecium candatum germinal nucleus morphology after UV irradiation

    International Nuclear Information System (INIS)

    Fokin, S.I.

    1982-01-01

    A study was made on morphologic changes of micronucleus (Mi) after whole-body ultraviolet (UV) irradiation of paramecia as well as after local irradiation of this nucleus or the area of macronucleus (Ma). The whole-body irradiation of its Ma part leads to generative nucleus growth in sizes and chromatin structure change, which is expressed in occurence of large chromatin bodies. Aftereffects of local action on Mi for viaable descendants are expressed in nucleus size transformation (usually in reduction), gaining ''comet-shaped'' form and probably in reduction of dna amount. Irradiation of Ma and total effect on cell cause Mi changes of reversible character. All morphologic changes of Mi after local ultraviolet irradiation are conserved in descendants and are not photoreactivated. Possible reasons for this phenomenon are discussed. The results obtained make it possible to speak about different mechanisms of action on Mi in the case of local and whole-body UV irradiation of cell. The effect of irradiated Ma on generative nucleus, but not direct damage of this nucleus is the reason for Mi morphologic reconstruction after whole-body action on paramecium

  4. A Ca sup 2+ influx associated with exocytosis is specifically abolished in a Paramecium exocytotic mutant

    Energy Technology Data Exchange (ETDEWEB)

    Kerboeuf, D.; Cohen, J. (Centre National de la Recherche Scientifique, Gif-sur-Yvette (France))

    1990-12-01

    A Paramecium possesses secretory organelles called trichocysts which are docked beneath the plasma membrane awaiting an external stimulus that triggers their exocytosis. Membrane fusion is the sole event provoked by the stimulation and can therefore be studied per se. Using 3 microM aminoethyl dextran as a vital secretagogue, we analyzed the movements of calcium (Ca{sup 2+}) during the discharge of trichocysts. We showed that (a) external Ca{sup 2+}, at least at 3 X 10(-7) M, is necessary for AED to induce exocytosis; (b) a dramatic and transient influx of Ca{sup 2+} as measured from {sup 45}Ca uptake is induced by AED; (c) this influx is independent of the well-characterized voltage-operated Ca{sup 2+} channels of the ciliary membranes since it persists in a mutant devoid of these channels; and (d) this influx is specifically abolished in one of the mutants unable to undergo exocytosis, nd12. We propose that the Ca{sup 2+} influx induced by AED reflects an increase in membrane permeability through the opening of novel Ca{sup 2+} channel or the activation of other Ca{sup 2+} transport mechanism in the plasma membrane. The resulting rise in cytosolic Ca{sup 2+} concentration would in turn induce membrane fusion. The mutation nd12 would affect a gene product involved in the control of plasma membrane permeability to Ca{sup 2+}, specifically related to membrane fusion.

  5. On the nature of species: insights from Paramecium and other ciliates

    Science.gov (United States)

    Hall, Meaghan S.; Katz, Laura A.

    2011-01-01

    The multiple species concepts currently in use by the scientific community (e.g. Morphological, Biological, Phylogenetic) are united in that they all aim to capture the process of divergence between populations. For example, the Biological Species Concept (BSC) defines a species as a natural group of organisms that is reproductively isolated from other such groups. Here we synthesize nearly a century of research on the ciliate genus Paramecium that highlights the shortcomings of our prevailing notions on the nature of species. In this lineage, there is discordance between morphology, mating behavior, and genetics, features assumed to be correlated, at least after sufficient time has passed, under all species concepts. Intriguingly, epigenetic phenomena are well documented in ciliates where they influence features such as germline/soma differentiation and mating type determination. Consequently, we hypothesize that divergence within ciliate populations is due to a dynamic interaction between genetic and epigenetic factors. The growing list of examples of epigenetic phenomena that potentially impact speciation (i.e. by influencing the dynamics of sex chromosomes, fate of hybrids, zygotic drive and genomic conflicts) suggests that interactions between genetics and epigenetics may also drive divergence in other eukaryotic lineages. PMID:21505762

  6. Epiplasmins and epiplasm in paramecium: the building of a submembraneous cytoskeleton.

    Science.gov (United States)

    Aubusson-Fleury, Anne; Bricheux, Geneviève; Damaj, Raghida; Lemullois, Michel; Coffe, Gérard; Donnadieu, Florence; Koll, France; Viguès, Bernard; Bouchard, Philippe

    2013-07-01

    In ciliates, basal bodies and associated appendages are bound to a submembrane cytoskeleton. In Paramecium, this cytoskeleton takes the form of a thin dense layer, the epiplasm, segmented into regular territories, the units where basal bodies are inserted. Epiplasmins, the main component of the epiplasm, constitute a large family of 51 proteins distributed in 5 phylogenetic groups, each characterized by a specific molecular design. By GFP-tagging, we analyzed their differential localisation and role in epiplasm building and demonstrated that: 1) The epiplasmins display a low turnover, in agreement with the maintenance of an epiplasm layer throughout the cell cycle; 2) Regionalisation of proteins from different groups allows us to define rim, core, ring and basal body epiplasmins in the interphase cell; 3) Their dynamics allows definition of early and late epiplasmins, detected early versus late in the duplication process of the units. Epiplasmins from each group exhibit a specific combination of properties. Core and rim epiplasmins are required to build a unit; ring and basal body epiplasmins seem more dispensable, suggesting that they are not required for basal body docking. We propose a model of epiplasm unit assembly highlighting its implication in structural heredity in agreement with the evolutionary history of epiplasmins. Copyright © 2013 Elsevier GmbH. All rights reserved.

  7. Spliced DNA sequences in the Paramecium germline: their properties and evolutionary potential.

    Science.gov (United States)

    Catania, Francesco; McGrath, Casey L; Doak, Thomas G; Lynch, Michael

    2013-01-01

    Despite playing a crucial role in germline-soma differentiation, the evolutionary significance of developmentally regulated genome rearrangements (DRGRs) has received scant attention. An example of DRGR is DNA splicing, a process that removes segments of DNA interrupting genic and/or intergenic sequences. Perhaps, best known for shaping immune-system genes in vertebrates, DNA splicing plays a central role in the life of ciliated protozoa, where thousands of germline DNA segments are eliminated after sexual reproduction to regenerate a functional somatic genome. Here, we identify and chronicle the properties of 5,286 sequences that putatively undergo DNA splicing (i.e., internal eliminated sequences [IESs]) across the genomes of three closely related species of the ciliate Paramecium (P. tetraurelia, P. biaurelia, and P. sexaurelia). The study reveals that these putative IESs share several physical characteristics. Although our results are consistent with excision events being largely conserved between species, episodes of differential IES retention/excision occur, may have a recent origin, and frequently involve coding regions. Our findings indicate interconversion between somatic--often coding--DNA sequences and noncoding IESs, and provide insights into the role of DNA splicing in creating potentially functional genetic innovation.

  8. Photoreactivation in Paramecium tetraurelia under conditions of various degrees of ozone layer depletion.

    Science.gov (United States)

    Takahashi, Akihisa; Kumatani, Toshihiro; Usui, Saori; Tsujimura, Ryoko; Seki, Takaharu; Morimoto, Kouichi; Ohnishi, Takeo

    2005-01-01

    Photoreactivation (PR) is an efficient survival mechanism that helps protect cells against the harmful effects of solar-ultraviolet (UV) radiation. The PR mechanism involves photolyase, just one enzyme, and can repair DNA damage, such as cyclobutane-pyrimidine dimers (CPD) induced by near-UV/blue light, a component of sunlight. Although the balance of near-UV/blue light and far-UV light reaching the Earth's surface could be altered by the atmospheric ozone layer's depletion, experiments simulating this environmental change and its possible effects on life have not yet been performed. To quantify the strength of UVB in sunlight reaching the Earth's surface, we measured the number of CPD generated in plasmid DNA after UVB irradiation or exposure to sunlight. To simulate the increase of solar-UV radiation resulting from the ozone layer depletion, Paramecium tetraurelia was exposed to UVB and/or sunlight in clear summer weather. PR recovery after exposure to sunlight was complete at a low dose rate of 0.2 J/m2 x s, but was less efficient when the dose rate was increased by a factor of 2.5 to 0.5 J/m2 x s. It is suggested that solar-UV radiation would not influence the cell growth of P. tetraurelia for the reason of high PR activity even when the ozone concentration was decreased 30% from the present levels.

  9. Phenotypic and genetic analysis of "Chameleon," a paramecium mutant with an enhanced sensitivity to magnesium.

    Science.gov (United States)

    Preston, R R; Hammond, J A

    1997-07-01

    Three mutant strains of Paramecium tetraurelia with an enhanced sensitivity to magnesium have been isolated. These new "Chameleon" mutants result from partial- or codominant mutations at a single locus, Cha. Whereas the wild type responded to 5 mM Mg2+ by swimming backward for 10-15 sec, Cha mutants responded with approximately 30 sec backward swimming. Electrophysiological analysis suggested that this behavior may be caused by slowing in the rate at which a Mg(2+)-specific ion conductance deactivates following membrane excitation. This would be consistent with an observed increase in the sensitivity of Cha mutants to nickel poisoning, since Ni2+ is also able to enter the cell via this pathway. More extensive behavioral analysis showed that Cha cells also overresponded to Na+, but there was no evidence for a defect in intracellular Ca2+ homeostasis that might account for a simultaneous enhancement of both the Mg2+ and Na+ conductances. The possibility that the Cha locus may encode a specific regulator of the Mg(2+)- and Na(+)-permeabilities is considered.

  10. Ultrastructural changes of the macronucleus of Paramecium bursaria after UV irradiation of the micronucleus

    Energy Technology Data Exchange (ETDEWEB)

    Fokin, S.I.; Borchsenius, O.N. (Leningradskij Gosudarstvennyj Univ. (USSR). Biologicheskij Nauchno-Issledovatel' skij Inst.)

    1982-01-01

    Dynamics of appearance of macronucleus (MA) fragments in vegetative cells of Paramecium bursaria after irradiation of their micronuclei (MI) with ultraviolet rays (exposure dose of 306 J/m/sup 2/) has been studied. Formation of invaginations of MA shell began in cells fixed already in 0.5-7 h after irradiation. In 2 and 6 days in the shell of cell MA- descendants of irradiated P. bursaria - deep invaginations appeared which resulted in the formation of marked MA blades. In the structure of MA chromatin elements visible changes have not been found during mentioned fixation periods. In 30 days after the irradiation of irradiated cell posterity MA often fragmentize, packing density and sizes of chromatin bands increasing. Near-nucleus areas of cytoplasma in 2.6 and 30 days are saturated with cisterns and channels of endoplasmic reticulum, obviously representing a certain kind of material ''depot'' necessary for increasing MA shell area in connection with its fragmentation. The MA fragmentation in P. bursaria descendants with irradiated MI points to the existence of interaction of these heteromorphous nuclei.

  11. Cultivation of macroscopic marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J.H.

    1982-11-01

    The red alga Gracilaria tikvahiae may be grown outdoors year-round in central Florida with yields averaging 35.5 g dry wt/m/sup 2/.day, greater than the most productive terrestrial plants. This occurs only when the plants are in a suspended culture, with vigorous aeration and an exchange of 25 or more culture volumes of enriched seawater per day, which is not cost-effective. A culture system was designed in which Gracilaria, stocked at a density of 2 kg wet wt/m/sup 2/, grows to double its biomass in one to two weeks; it is then harvested to its starting density, and anaerobically digested to methane. The biomass is soaked for 6 hours in the digester residue, storing enough nutrients for two weeks' growth in unenriched seawater. The methane is combusted for energy and the waste gas is fed to the culture to provide mixing and CO/sub 2/, eliminating the need for aeration and seawater exchange. The green alga Ulva lactuca, unlike Gracilaria, uses bicarbonate as a photosynthesis carbon source, and can grow at high pH, with little or no free CO/sub 2/. It can therefore produce higher yields than Gracilaria in low water exchange conditions. It is also more efficiently converted to methane than is Gracilaria, but cannot tolerate Florida's summer temperatures so cannot be grown year-round. Attempts are being made to locate or produce a high-temperature tolerant strain.

  12. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savceno, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent; Veerman, Frits; Frank, J.; van der Mei, R.; den Boer, A.; Bosman, J.; Bouman, N.; van Dam, S.; Verhoef, C.

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runo water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a

  13. SSMILes: Measuring the Nutrient Tolerance of Algae.

    Science.gov (United States)

    Hedgepeth, David J.

    1995-01-01

    Presents an activity integrating mathematics and science intended to introduce students to the use of metric measurement of mass as a way to increase the meaningfulness of observations about variables in life sciences. Involves measuring the nutrient tolerance of algae. Contains a reproducible algae nutrient graph. (Author/MKR)

  14. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savcenco, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent; Veerman, Frits

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runoff water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a

  15. Algae commensal community in Genlisea traps

    Directory of Open Access Journals (Sweden)

    Konrad Wołowski

    2011-01-01

    Full Text Available The community of algae occurring in Genlisea traps and on the external traps surface in laboratory conditions were studied. A total of 29 taxa were found inside the traps, with abundant diatoms, green algae (Chlamydophyceae and four morphotypes of chrysophytes stomatocysts. One morphotype is described as new for science. There are two ways of algae getting into Genlisea traps. The majority of those recorded inside the traps, are mobile; swimming freely by flagella or moving exuding mucilage like diatoms being ablate to colonize the traps themselves. Another possibility is transport of algae by invertebrates such as mites and crustaceans. In any case algae in the Genlisea traps come from the surrounding environment. Two dominant groups of algae (Chladymonas div. and diatoms in the trap environment, show ability to hydrolyze phosphomonoseters. We suggest that algae in carnivorous plant traps can compete with plant (host for organic phosphate (phosphomonoseters. From the spectrum and ecological requirements of algal species found in the traps, environment inside the traps seems to be acidic. However, further studies are needed to test the relations between algae and carnivorous plants both in laboratory conditions and in the natural environment. All the reported taxa are described briefly and documented with 74 LM and SEM micrographs.

  16. The Paramecium germline genome provides a niche for intragenic parasitic DNA: evolutionary dynamics of internal eliminated sequences.

    Science.gov (United States)

    Arnaiz, Olivier; Mathy, Nathalie; Baudry, Céline; Malinsky, Sophie; Aury, Jean-Marc; Denby Wilkes, Cyril; Garnier, Olivier; Labadie, Karine; Lauderdale, Benjamin E; Le Mouël, Anne; Marmignon, Antoine; Nowacki, Mariusz; Poulain, Julie; Prajer, Malgorzata; Wincker, Patrick; Meyer, Eric; Duharcourt, Sandra; Duret, Laurent; Bétermier, Mireille; Sperling, Linda

    2012-01-01

    Insertions of parasitic DNA within coding sequences are usually deleterious and are generally counter-selected during evolution. Thanks to nuclear dimorphism, ciliates provide unique models to study the fate of such insertions. Their germline genome undergoes extensive rearrangements during development of a new somatic macronucleus from the germline micronucleus following sexual events. In Paramecium, these rearrangements include precise excision of unique-copy Internal Eliminated Sequences (IES) from the somatic DNA, requiring the activity of a domesticated piggyBac transposase, PiggyMac. We have sequenced Paramecium tetraurelia germline DNA, establishing a genome-wide catalogue of -45,000 IESs, in order to gain insight into their evolutionary origin and excision mechanism. We obtained direct evidence that PiggyMac is required for excision of all IESs. Homology with known P. tetraurelia Tc1/mariner transposons, described here, indicates that at least a fraction of IESs derive from these elements. Most IES insertions occurred before a recent whole-genome duplication that preceded diversification of the P. aurelia species complex, but IES invasion of the Paramecium genome appears to be an ongoing process. Once inserted, IESs decay rapidly by accumulation of deletions and point substitutions. Over 90% of the IESs are shorter than 150 bp and present a remarkable size distribution with a -10 bp periodicity, corresponding to the helical repeat of double-stranded DNA and suggesting DNA loop formation during assembly of a transpososome-like excision complex. IESs are equally frequent within and between coding sequences; however, excision is not 100% efficient and there is selective pressure against IES insertions, in particular within highly expressed genes. We discuss the possibility that ancient domestication of a piggyBac transposase favored subsequent propagation of transposons throughout the germline by allowing insertions in coding sequences, a fraction of the

  17. Multigene Family Encoding 3′,5′-Cyclic-GMP-Dependent Protein Kinases in Paramecium tetraurelia Cells

    Science.gov (United States)

    Kissmehl, Roland; Krüger, Tim P.; Treptau, Tilman; Froissard, Marine; Plattner, Helmut

    2006-01-01

    In the ciliate Paramecium tetraurelia, 3′,5′-cyclic GMP (cGMP) is one of the second messengers involved in several signal transduction pathways. The enzymes for its production and degradation are well established for these cells, whereas less is known about the potential effector proteins. On the basis of a current Paramecium genome project, we have identified a multigene family with at least 35 members, all of which encode cGMP-dependent protein kinases (PKGs). They can be classified into 16 subfamilies with several members each. Two of the genes, PKG1-1 and PKG2-1, were analyzed in more detail after molecular cloning. They encode monomeric enzymes of 770 and 819 amino acids, respectively, whose overall domain organization resembles that in higher eukaryotes. The enzymes contain a regulatory domain of two tandem cyclic nucleotide-binding sites flanked by an amino-terminal region for intracellular localization and a catalytic domain with highly conserved regions for ATP binding and catalysis. However, some Paramecium PKGs show a different structure. In Western blots, PKGs are detected both as cytosolic and as structure-bound forms. Immunofluorescence labeling shows enrichment in the cell cortex, notably around the dense-core secretory vesicles (trichocysts), as well as in cilia. Immunogold electron microscopy analysis reveals consistent labeling of ciliary membranes, of the membrane complex composed of cell membrane and cortical Ca2+ stores, and of regions adjacent to ciliary basal bodies, trichocysts, and trafficking vesicles. Since PKGs (re)phosphorylate the exocytosis-sensitive phosphoprotein pp63/pf upon stimulation, the role of PKGs during stimulated exocytosis is discussed, in addition to a role in ciliary beat regulation. PMID:16400170

  18. The conjugation-specific Die5 protein is required for development of the somatic nucleus in both Paramecium and Tetrahymena.

    Science.gov (United States)

    Matsuda, Atsushi; Shieh, Annie Wan-Yi; Chalker, Douglas L; Forney, James D

    2010-07-01

    Development in ciliated protozoa involves extensive genome reorganization within differentiating macronuclei, which shapes the somatic genome of the next vegetative generation. Major events of macronuclear differentiation include excision of internal eliminated sequences (IESs), chromosome fragmentation, and genome amplification. Proteins required for these events include those with homology throughout eukaryotes as well as proteins apparently unique to ciliates. In this study, we identified the ciliate-specific Defective in IES Excision 5 (DIE5) genes of Paramecium tetraurelia (PtDIE5) and Tetrahymena thermophila (TtDIE5) as orthologs that encode nuclear proteins expressed exclusively during development. Abrogation of PtDie5 protein (PtDie5p) function by RNA interference (RNAi)-mediated silencing or TtDie5p by gene disruption resulted in the failure of developing macronuclei to differentiate into new somatic nuclei. Tetrahymena DeltaDIE5 cells arrested late in development and failed to complete genome amplification, whereas RNAi-treated Paramecium cells highly amplified new macronuclear DNA before the failure in differentiation, findings that highlight clear differences in the biology of these distantly related species. Nevertheless, IES excision and chromosome fragmentation failed to occur in either ciliate, which strongly supports that Die5p is a critical player in these processes. In Tetrahymena, loss of zygotic expression during development was sufficient to block nuclear differentiation. This observation, together with the finding that knockdown of Die5p in Paramecium still allows genome amplification, indicates that this protein acts late in macronuclear development. Even though DNA rearrangements in these two ciliates look to be quite distinct, analysis of DIE5 establishes the action of a conserved mechanism within the genome reorganization pathway.

  19. The Conjugation-Specific Die5 Protein Is Required for Development of the Somatic Nucleus in both Paramecium and Tetrahymena▿

    Science.gov (United States)

    Matsuda, Atsushi; Shieh, Annie Wan-Yi; Chalker, Douglas L.; Forney, James D.

    2010-01-01

    Development in ciliated protozoa involves extensive genome reorganization within differentiating macronuclei, which shapes the somatic genome of the next vegetative generation. Major events of macronuclear differentiation include excision of internal eliminated sequences (IESs), chromosome fragmentation, and genome amplification. Proteins required for these events include those with homology throughout eukaryotes as well as proteins apparently unique to ciliates. In this study, we identified the ciliate-specific Defective in IES Excision 5 (DIE5) genes of Paramecium tetraurelia (PtDIE5) and Tetrahymena thermophila (TtDIE5) as orthologs that encode nuclear proteins expressed exclusively during development. Abrogation of PtDie5 protein (PtDie5p) function by RNA interference (RNAi)-mediated silencing or TtDie5p by gene disruption resulted in the failure of developing macronuclei to differentiate into new somatic nuclei. Tetrahymena ΔDIE5 cells arrested late in development and failed to complete genome amplification, whereas RNAi-treated Paramecium cells highly amplified new macronuclear DNA before the failure in differentiation, findings that highlight clear differences in the biology of these distantly related species. Nevertheless, IES excision and chromosome fragmentation failed to occur in either ciliate, which strongly supports that Die5p is a critical player in these processes. In Tetrahymena, loss of zygotic expression during development was sufficient to block nuclear differentiation. This observation, together with the finding that knockdown of Die5p in Paramecium still allows genome amplification, indicates that this protein acts late in macronuclear development. Even though DNA rearrangements in these two ciliates look to be quite distinct, analysis of DIE5 establishes the action of a conserved mechanism within the genome reorganization pathway. PMID:20495055

  20. The Paramecium germline genome provides a niche for intragenic parasitic DNA: evolutionary dynamics of internal eliminated sequences.

    Directory of Open Access Journals (Sweden)

    Olivier Arnaiz

    Full Text Available Insertions of parasitic DNA within coding sequences are usually deleterious and are generally counter-selected during evolution. Thanks to nuclear dimorphism, ciliates provide unique models to study the fate of such insertions. Their germline genome undergoes extensive rearrangements during development of a new somatic macronucleus from the germline micronucleus following sexual events. In Paramecium, these rearrangements include precise excision of unique-copy Internal Eliminated Sequences (IES from the somatic DNA, requiring the activity of a domesticated piggyBac transposase, PiggyMac. We have sequenced Paramecium tetraurelia germline DNA, establishing a genome-wide catalogue of -45,000 IESs, in order to gain insight into their evolutionary origin and excision mechanism. We obtained direct evidence that PiggyMac is required for excision of all IESs. Homology with known P. tetraurelia Tc1/mariner transposons, described here, indicates that at least a fraction of IESs derive from these elements. Most IES insertions occurred before a recent whole-genome duplication that preceded diversification of the P. aurelia species complex, but IES invasion of the Paramecium genome appears to be an ongoing process. Once inserted, IESs decay rapidly by accumulation of deletions and point substitutions. Over 90% of the IESs are shorter than 150 bp and present a remarkable size distribution with a -10 bp periodicity, corresponding to the helical repeat of double-stranded DNA and suggesting DNA loop formation during assembly of a transpososome-like excision complex. IESs are equally frequent within and between coding sequences; however, excision is not 100% efficient and there is selective pressure against IES insertions, in particular within highly expressed genes. We discuss the possibility that ancient domestication of a piggyBac transposase favored subsequent propagation of transposons throughout the germline by allowing insertions in coding sequences, a

  1. Advances in genetic engineering of marine algae.

    Science.gov (United States)

    Qin, Song; Lin, Hanzhi; Jiang, Peng

    2012-01-01

    Algae are a component of bait sources for animal aquaculture, and they produce abundant valuable compounds for the chemical industry and human health. With today's fast growing demand for algae biofuels and the profitable market for cosmetics and pharmaceuticals made from algal natural products, the genetic engineering of marine algae has been attracting increasing attention as a crucial systemic technology to address the challenge of the biomass feedstock supply for sustainable industrial applications and to modify the metabolic pathway for the more efficient production of high-value products. Nevertheless, to date, only a few marine algae species can be genetically manipulated. In this article, an updated account of the research progress in marine algal genomics is presented along with methods for transformation. In addition, vector construction and gene selection strategies are reviewed. Meanwhile, a review on the progress of bioreactor technologies for marine algae culture is also revisited. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Cars will be fed on algae

    International Nuclear Information System (INIS)

    Peltier, G.

    2012-01-01

    The development of the first and second generations of bio-fuels has led to a rise in food prices and the carbon balance sheet is less good than expected. Great hopes have been put on unicellular algae for they can synthesize oils, sugar and even hydrogen and the competition with food production is far less harsh than with actual bio-fuels. Moreover, when you grow micro-algae, the loss of water through evaporation is less important than in the case of intensive farm cultures. In 2009 10.000 tonnes of micro-algae were produced worldwide, they were mainly used for the production of fish food and of complements for humane food (fat acids and antioxidants). Different research programs concern unicellular algae: they aim at modifying micro-algae genetically in order to give them a higher productivity or to make them produce an oil more adapted for motor fuel or more easily recoverable. (A.C.)

  3. Potential biomedical applications of marine algae.

    Science.gov (United States)

    Wang, Hui-Min David; Li, Xiao-Chun; Lee, Duu-Jong; Chang, Jo-Shu

    2017-11-01

    Functional components extracted from algal biomass are widely used as dietary and health supplements with a variety of applications in food science and technology. In contrast, the applications of algae in dermal-related products have received much less attention, despite that algae also possess high potential for the uses in anti-infection, anti-aging, skin-whitening, and skin tumor treatments. This review, therefore, focuses on integrating studies on algae pertinent to human skin care, health and therapy. The active compounds in algae related to human skin treatments are mentioned and the possible mechanisms involved are described. The main purpose of this review is to identify serviceable algae functions in skin treatments to facilitate practical applications in this high-potential area. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Streptophyte algae and the origin of embryophytes.

    Science.gov (United States)

    Becker, Burkhard; Marin, Birger

    2009-05-01

    Land plants (embryophytes) evolved from streptophyte green algae, a small group of freshwater algae ranging from scaly, unicellular flagellates (Mesostigma) to complex, filamentous thalli with branching, cell differentiation and apical growth (Charales). Streptophyte algae and embryophytes form the division Streptophyta, whereas the remaining green algae are classified as Chlorophyta. The Charales (stoneworts) are often considered to be sister to land plants, suggesting progressive evolution towards cellular complexity within streptophyte green algae. Many cellular (e.g. phragmoplast, plasmodesmata, hexameric cellulose synthase, structure of flagellated cells, oogamous sexual reproduction with zygote retention) and physiological characters (e.g. type of photorespiration, phytochrome system) originated within streptophyte algae. Phylogenetic studies have demonstrated that Mesostigma (flagellate) and Chlorokybus (sarcinoid) form the earliest divergence within streptophytes, as sister to all other Streptophyta including embryophytes. The question whether Charales, Coleochaetales or Zygnematales are the sister to embryophytes is still (or, again) hotly debated. Projects to study genome evolution within streptophytes including protein families and polyadenylation signals have been initiated. In agreement with morphological and physiological features, many molecular traits believed to be specific for embryophytes have been shown to predate the Chlorophyta/Streptophyta split, or to have originated within streptophyte algae. Molecular phylogenies and the fossil record allow a detailed reconstruction of the early evolutionary events that led to the origin of true land plants, and shaped the current diversity and ecology of streptophyte green algae and their embryophyte descendants. The Streptophyta/Chlorophyta divergence correlates with a remarkably conservative preference for freshwater/marine habitats, and the early freshwater adaptation of streptophyte algae was a major

  5. Algae biodiesel - a feasibility report

    Directory of Open Access Journals (Sweden)

    Gao Yihe

    2012-04-01

    Full Text Available Abstract Background Algae biofuels have been studied numerous times including the Aquatic Species program in 1978 in the U.S., smaller laboratory research projects and private programs. Results Using Molina Grima 2003 and Department of Energy figures, captial costs and operating costs of the closed systems and open systems were estimated. Cost per gallon of conservative estimates yielded $1,292.05 and $114.94 for closed and open ponds respectively. Contingency scenarios were generated in which cost per gallon of closed system biofuels would reach $17.54 under the generous conditions of 60% yield, 50% reduction in the capital costs and 50% hexane recovery. Price per gallon of open system produced fuel could reach $1.94 under generous assumptions of 30% yield and $0.2/kg CO2. Conclusions Current subsidies could allow biodiesel to be produced economically under the generous conditions specified by the model.

  6. Algae biodiesel - a feasibility report

    Science.gov (United States)

    2012-01-01

    Background Algae biofuels have been studied numerous times including the Aquatic Species program in 1978 in the U.S., smaller laboratory research projects and private programs. Results Using Molina Grima 2003 and Department of Energy figures, captial costs and operating costs of the closed systems and open systems were estimated. Cost per gallon of conservative estimates yielded $1,292.05 and $114.94 for closed and open ponds respectively. Contingency scenarios were generated in which cost per gallon of closed system biofuels would reach $17.54 under the generous conditions of 60% yield, 50% reduction in the capital costs and 50% hexane recovery. Price per gallon of open system produced fuel could reach $1.94 under generous assumptions of 30% yield and $0.2/kg CO2. Conclusions Current subsidies could allow biodiesel to be produced economically under the generous conditions specified by the model. PMID:22540986

  7. Identification and functional characterization of an uncharacterized antimicrobial peptide from a ciliate Paramecium caudatum.

    Science.gov (United States)

    Cui, Pengfei; Dong, Yuan; Li, Zhijian; Zhang, Yubo; Zhang, Shicui

    2016-07-01

    The global ever-growing concerns about multi-drug resistant (MDR) microbes leads to urgent demands for exploration of new antibiotics including antimicrobial peptides (AMPs). Here we demonstrated that a cDNA from Ciliata Paramecium caudatum, designated Pcamp1, coded for a protein with features characteristic of AMPs, which is not homologous to any AMPs currently known. Both the C-terminal 91 amino acid residues of PcAMP1, cPcAMP1, expressed in Escherichia coli and the C-terminal 26 amino acid residues (predicted mature AMP), cPcAMP1/26, synthesized, underwent a coil-to-helix transition in the presence of TFE, SDS or DPC. Functional assays revealed that cPcAMP1 and cPcAMP1/26 were both able to kill Aeromonas hydrophila and Staphylococcus aureus. ELISA showed that cPcAMP1 and cPcAMP1/26 were able to bind to microbe-associated molecular pattern molecules LPS and LTA, which was further corroborated by the observations that cPcAMP1 could deposit onto the bacterial membranes. Importantly, both cPcAMP1 and cPcAMP1/26 were able to induce bacterial membrane permeabilization and depolarization, and to increase intracellular ROS levels. Additionally, cPcAMP1 and cPcAMP1/26 were not cytotoxic to mammalian cells. Taken together, our results show that PcAMP1 is a potential AMP with a membrane selectivity towards bacterial cells, which renders it a promising template for the design of novel peptide antibiotics against MDR microbes. It also shows that use of signal conserved sequence of AMPs can be an effective tool to identify potential AMPs across different animal classes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Highly precise and developmentally programmed genome assembly in Paramecium requires ligase IV-dependent end joining.

    Science.gov (United States)

    Kapusta, Aurélie; Matsuda, Atsushi; Marmignon, Antoine; Ku, Michael; Silve, Aude; Meyer, Eric; Forney, James D; Malinsky, Sophie; Bétermier, Mireille

    2011-04-01

    During the sexual cycle of the ciliate Paramecium, assembly of the somatic genome includes the precise excision of tens of thousands of short, non-coding germline sequences (Internal Eliminated Sequences or IESs), each one flanked by two TA dinucleotides. It has been reported previously that these genome rearrangements are initiated by the introduction of developmentally programmed DNA double-strand breaks (DSBs), which depend on the domesticated transposase PiggyMac. These DSBs all exhibit a characteristic geometry, with 4-base 5' overhangs centered on the conserved TA, and may readily align and undergo ligation with minimal processing. However, the molecular steps and actors involved in the final and precise assembly of somatic genes have remained unknown. We demonstrate here that Ligase IV and Xrcc4p, core components of the non-homologous end-joining pathway (NHEJ), are required both for the repair of IES excision sites and for the circularization of excised IESs. The transcription of LIG4 and XRCC4 is induced early during the sexual cycle and a Lig4p-GFP fusion protein accumulates in the developing somatic nucleus by the time IES excision takes place. RNAi-mediated silencing of either gene results in the persistence of free broken DNA ends, apparently protected against extensive resection. At the nucleotide level, controlled removal of the 5'-terminal nucleotide occurs normally in LIG4-silenced cells, while nucleotide addition to the 3' ends of the breaks is blocked, together with the final joining step, indicative of a coupling between NHEJ polymerase and ligase activities. Taken together, our data indicate that IES excision is a "cut-and-close" mechanism, which involves the introduction of initiating double-strand cleavages at both ends of each IES, followed by DSB repair via highly precise end joining. This work broadens our current view on how the cellular NHEJ pathway has cooperated with domesticated transposases for the emergence of new mechanisms

  9. Highly precise and developmentally programmed genome assembly in Paramecium requires ligase IV-dependent end joining.

    Directory of Open Access Journals (Sweden)

    Aurélie Kapusta

    2011-04-01

    Full Text Available During the sexual cycle of the ciliate Paramecium, assembly of the somatic genome includes the precise excision of tens of thousands of short, non-coding germline sequences (Internal Eliminated Sequences or IESs, each one flanked by two TA dinucleotides. It has been reported previously that these genome rearrangements are initiated by the introduction of developmentally programmed DNA double-strand breaks (DSBs, which depend on the domesticated transposase PiggyMac. These DSBs all exhibit a characteristic geometry, with 4-base 5' overhangs centered on the conserved TA, and may readily align and undergo ligation with minimal processing. However, the molecular steps and actors involved in the final and precise assembly of somatic genes have remained unknown. We demonstrate here that Ligase IV and Xrcc4p, core components of the non-homologous end-joining pathway (NHEJ, are required both for the repair of IES excision sites and for the circularization of excised IESs. The transcription of LIG4 and XRCC4 is induced early during the sexual cycle and a Lig4p-GFP fusion protein accumulates in the developing somatic nucleus by the time IES excision takes place. RNAi-mediated silencing of either gene results in the persistence of free broken DNA ends, apparently protected against extensive resection. At the nucleotide level, controlled removal of the 5'-terminal nucleotide occurs normally in LIG4-silenced cells, while nucleotide addition to the 3' ends of the breaks is blocked, together with the final joining step, indicative of a coupling between NHEJ polymerase and ligase activities. Taken together, our data indicate that IES excision is a "cut-and-close" mechanism, which involves the introduction of initiating double-strand cleavages at both ends of each IES, followed by DSB repair via highly precise end joining. This work broadens our current view on how the cellular NHEJ pathway has cooperated with domesticated transposases for the emergence of new

  10. Role of delta-tubulin and the C-tubule in assembly of Paramecium basal bodies

    Directory of Open Access Journals (Sweden)

    Beisson Janine

    2001-03-01

    Full Text Available Abstract Background A breakthrough in the understanding of centriole assembly was provided by the characterization of the UNI3 gene in Chlamydomonas. Deletion of this gene, found to encode a novel member of the tubulin superfamily, delta-tubulin, results in the loss of the C-tubule, in the nine microtubule triplets which are the hallmark of centrioles and basal bodies. Delta-tubulin homologs have been identified in the genomes of mammals and protozoa, but their phylogenetic relationships are unclear and their function is not yet known. Results Using the method of gene-specific silencing, we have inactivated the Paramecium delta-tubulin gene, which was recently identified. This inactivation leads to loss of the C-tubule in all basal bodies, without any effect on ciliogenesis. This deficiency does not directly affect basal body duplication, but perturbs the cortical cytoskeleton, progressively leading to mislocalization and loss of basal bodies and to altered cell size and shape. Furthermore, additional loss of B- and even A-tubules at one or more triplet sites are observed: around these incomplete cylinders, the remaining doublets are nevertheless positioned according to the native ninefold symmetry. Conclusions The fact that in two distinct phyla, delta-tubulin plays a similar role provides a new basis for interpreting phylogenetic relationships among delta-tubulins. The role of delta-tubulin in C-tubule assembly reveals that tubulins contribute subtle specificities at microtubule nucleation sites. Our observations also demonstrate the existence of a prepattern for the ninefold symmetry of the organelle which is maintained even if less than 9 triplets develop.

  11. Intraspecific differentiation of Paramecium novaurelia strains (Ciliophora, Protozoa) inferred from phylogenetic analysis of ribosomal and mitochondrial DNA variation.

    Science.gov (United States)

    Tarcz, Sebastian

    2013-01-01

    Paramecium novaurelia Beale and Schneller, 1954, was first found in Scotland and is known to occur mainly in Europe, where it is the most common species of the P. aurelia complex. In recent years, two non-European localities have been described: Turkey and the United States of America. This article presents the analysis of intraspecific variability among 25 strains of P. novaurelia with the application of ribosomal and mitochondrial loci (ITS1-5.8S-ITS2, 5' large subunit rDNA (5'LSU rDNA) and cytochrome c oxidase subunit 1 (COI) mtDNA). The mean distance observed for all of the studied P. novaurelia sequence pairs was p=0.008/0.016/0.092 (ITS1-5.8S-ITS2/5'LSU rDNA/COI). Phylogenetic trees (NJ/MP/BI) based on a comparison of all of the analysed sequences show that the studied strains of P. novaurelia form a distinct clade, separate from the P. caudatum outgroup, and are divided into two clusters (A and B) and two branches (C and D). The occurrence of substantial genetic differentiation within P. novaurelia, confirmed by the analysed DNA fragments, indicates a rapid evolution of particular species within the Paramecium genus. Copyright © 2012 Elsevier GmbH. All rights reserved.

  12. Paramecium: a promising non-animal bioassay to study the effect of 808 nm infrared diode laser photobiomodulation.

    Science.gov (United States)

    Amaroli, Andrea; Parker, Steven; Dorigo, Gianluca; Benedicenti, Alberico; Benedicenti, Stefano

    2015-01-01

    Photobiostimulation and photobiomodulation (PBM) are terms applied to the manipulation of cellular behavior using low intensity light sources, which works on the principle of inducing a biological response through energy transfer. The aim of this investigation was to identify a laboratory assay to test the effect of an infrared diode laser light (808 nm) on cell fission rate. Sixty cells of Paramecium primaurelia were divided in two groups of 30. The first group (test group) was irradiated, at a temperature of 24°C, for 50 sec by a 808 nm diode laser with a flat top handpiece [1 cm of spot diameter, 1 W in continuous wave (CW), 50 sec irradiation time, 64 J/cm(2) of fluence]. The second group (control group) received no laser irradiation. All cells were transferred onto a depression slide, fed, and incubated in a moist chamber at a temperature of 24°C. The cells were exposed and monitored for 10 consecutive fission rates. Changes in temperature and pH were also evaluated. The exposed cells had a fission rate rhythm faster than the control cells, showing a binary fission significantly (pParamecium's lettuce infusion medium were observed. The 808 nm infrared diode laser light, at the irradiation parameters used in our work, results in a precocious fission rate in P. primaurelia cells, probably through an increase in metabolic activity, secondary to an energy transfer.

  13. Ultrastructural changes of the UV-irradiated micronucleus in vegetative cells of paramecium bursaria and its functional importance

    International Nuclear Information System (INIS)

    Borkhsenius, O.N.; Fokin, S.I.

    1982-01-01

    Ultrastructural micronucleus (MI) changes of vegetative cells in Paramecium bursaria in 0.5-7 h after MI ultraviolet irradiation and cell posterity with irradiated MI after different periods (2.6 and 30 days, three years) after ultraviolet irradiation have been studied. It is established that MI irradiation at a dose of 306J/m 2 doesn't result in its loss in postradiation generations however in posterity MI considerable ultrastructural changes occur. In two days after operation the shell of descendant MI of irradiated Paramecium bursaria forms multiple blades; small chromatin blocks considerably increase in sizes and, as a rule, occupy the central position in a nucleus. During later periods afeter irradiation (6 days) density of chromatin elements in MI begins to change. By the 30-st day in MI fine-fibrillar karyoplasm detected are only not numerous chromatin structures scattered in disorder. The results obtained point to the existence of the ''cryptic'' type MIs are not revealed at the light-optical level but preserved in a series of postradiation generations. The presence of such MIs in viable cultures of P. bursaria confirms indirectly MI significance in vegetatic life of P. bursaria

  14. Avaliação experimental do efeito tóxico de metais em Paramecium caudatum Ehrenberg, 1833.

    Directory of Open Access Journals (Sweden)

    Fernandes Martins Nicolas

    2014-07-01

    Full Text Available No presente trabalho o protozoário ciliado Paramecium caudatum Ehrenberg, 1833 foi isolado da Represa do Monjolinho (São Carlos-SP e mantido em cultura monoxênica sob condições  de cultivo previamente estabelecidas, e seguindo recomendações de otimização para cultivo do protozoário; usado em experimentos para avaliar a toxicidade de dezessete metais sob a forma de íons cloreto (alumínio, arsênio, bário, cádmio, chumbo, cobalto, cobre, cromo, estanho, estrôncio, ferro (II, lítio, manganês, mercúrio, molibdênio, níquel, e zinco e nitrato de prata; visando a possibilidade de sua utilização como organismo-teste e indicador ambiental em um bioensaio padronizado. Foi verificado previamente, por meio dos ensaios que o Paramecium caudatum apresenta pouca tolerância aos metais usados nos testes, revelando uma maior tolerância ao Lítio, sugere que se realize testes definitivos com  os resultados aqui obtidos visando estabelecer criteriosamente através de testes de concetração letal a 50% (LC50-24h., visando estabelecer com maior precisão as faixas de mortalidade e tolerância do protozoário para cada íon metal aqui utilizado nos ensaios preliminares.

  15. Inactivation of Ca2+-induced ciliary reversal by high-salt extraction in the cilia of Paramecium.

    Science.gov (United States)

    Kutomi, Osamu; Seki, Makoto; Nakamura, Shogo; Kamachi, Hiroyuki; Noguchi, Munenori

    2013-10-01

    Intracellular Ca(2+) induces ciliary reversal and backward swimming in Paramecium. However, it is not known how the Ca(2+) signal controls the motor machinery to induce ciliary reversal. We found that demembranated cilia on the ciliated cortical sheets from Paramecium caudatum lost the ability to undergo ciliary reversal after brief extraction with a solution containing 0.5 M KCl. KNO(3), which is similar to KCl with respect to chaotropic effect; it had the same effect as that of KCl on ciliary response. Cyclic AMP antagonizes Ca(2+)-induced ciliary reversal. Limited trypsin digestion prevents endogenous A-kinase and cAMP-dependent phosphorylation of an outer arm dynein light chain and induces ciliary reversal. However, the trypsin digestion prior to the high-salt extraction did not affect the inhibition of Ca(2+)-induced ciliary reversal caused by the high-salt extraction. Furthermore, during the course of the high-salt extraction, some axonemal proteins were extracted from ciliary axonemes, suggesting that they may be responsible for Ca(2+)-induced ciliary reversal.

  16. Identification, Localization, and Functional Implications of the Microdomain-Forming Stomatin Family in the Ciliated Protozoan Paramecium tetraurelia

    Science.gov (United States)

    Stuermer, Claudia A. O.; Plattner, Helmut

    2013-01-01

    The SPFH protein superfamily is assumed to occur universally in eukaryotes, but information from protozoa is scarce. In the Paramecium genome, we found only Stomatins, 20 paralogs grouped in 8 families, STO1 to STO8. According to cDNA analysis, all are expressed, and molecular modeling shows the typical SPFH domain structure for all subgroups. For further analysis we used family-specific sequences for fluorescence and immunogold labeling, gene silencing, and functional tests. With all family members tested, we found a patchy localization at/near the cell surface and on vesicles. The Sto1p and Sto4p families are also associated with the contractile vacuole complex. Sto4p also makes puncta on some food vacuoles and is abundant on vesicles recycling from the release site of spent food vacuoles to the site of nascent food vacuole formation. Silencing of the STO1 family reduces mechanosensitivity (ciliary reversal upon touching an obstacle), thus suggesting relevance for positioning of mechanosensitive channels in the plasmalemma. Silencing of STO4 members increases pulsation frequency of the contractile vacuole complex and reduces phagocytotic activity of Paramecium cells. In summary, Sto1p and Sto4p members seem to be involved in positioning specific superficial and intracellular microdomain-based membrane components whose functions may depend on mechanosensation (extracellular stimuli and internal osmotic pressure). PMID:23376944

  17. Polymorphism of Paramecium pentaurelia (Ciliophora, Oligohymenophorea) strains revealed by rDNA and mtDNA sequences.

    Science.gov (United States)

    Przyboś, Ewa; Tarcz, Sebastian; Greczek-Stachura, Magdalena; Surmacz, Marta

    2011-05-01

    Paramecium pentaurelia is one of 15 known sibling species of the Paramecium aurelia complex. It is recognized as a species showing no intra-specific differentiation on the basis of molecular fingerprint analyses, whereas the majority of other species are polymorphic. This study aimed at assessing genetic polymorphism within P. pentaurelia including new strains recently found in Poland (originating from two water bodies, different years, seasons, and clones of one strain) as well as strains collected from distant habitats (USA, Europe, Asia), and strains representing other species of the complex. We compared two DNA fragments: partial sequences (349 bp) of the LSU rDNA and partial sequences (618 bp) of cytochrome B gene. A correlation between the geographical origin of the strains and the genetic characteristics of their genotypes was not observed. Different genotypes were found in Kraków in two types of water bodies (Opatkowice-natural pond; Jordan's Park-artificial pond). Haplotype diversity within a single water body was not recorded. Likewise, seasonal haplotype differences between the strains within the artificial water body, as well as differences between clones originating from one strain, were not detected. The clustering of some strains belonging to different species was observed in the phylogenies. Copyright © 2010 Elsevier GmbH. All rights reserved.

  18. Primary and secondary siRNA synthesis triggered by RNAs from food bacteria in the ciliate Paramecium tetraurelia

    Science.gov (United States)

    Carradec, Quentin; Götz, Ulrike; Arnaiz, Olivier; Pouch, Juliette; Simon, Martin; Meyer, Eric; Marker, Simone

    2015-01-01

    In various organisms, an efficient RNAi response can be triggered by feeding cells with bacteria producing double-stranded RNA (dsRNA) against an endogenous gene. However, the detailed mechanisms and natural functions of this pathway are not well understood in most cases. Here, we studied siRNA biogenesis from exogenous RNA and its genetic overlap with endogenous RNAi in the ciliate Paramecium tetraurelia by high-throughput sequencing. Using wild-type and mutant strains deficient for dsRNA feeding we found that high levels of primary siRNAs of both strands are processed from the ingested dsRNA trigger by the Dicer Dcr1, the RNA-dependent RNA polymerases Rdr1 and Rdr2 and other factors. We further show that this induces the synthesis of secondary siRNAs spreading along the entire endogenous mRNA, demonstrating the occurrence of both 3′-to-5′ and 5′-to-3′ transitivity for the first time in the SAR clade of eukaryotes (Stramenopiles, Alveolates, Rhizaria). Secondary siRNAs depend on Rdr2 and show a strong antisense bias; they are produced at much lower levels than primary siRNAs and hardly contribute to RNAi efficiency. We further provide evidence that the Paramecium RNAi machinery also processes single-stranded RNAs from its bacterial food, broadening the possible natural functions of exogenously induced RNAi in this organism. PMID:25593325

  19. Ultrastructural changes of the UV-irradiated micronucleus in vegetative cells of Paramecium bursaria and its functional importance

    Energy Technology Data Exchange (ETDEWEB)

    Borkhsenius, O.N.; Fokin, S.I. (Leningradskij Gosudarstvennyj Univ. (USSR). Biologicheskij Nauchno-Issledovatel' skij Inst.)

    1982-01-01

    Ultrastructural micronucleus (MI) changes of vegetative cells in Paramecium bursaria in 0.5-7 h after MI ultraviolet irradiation and cell posterity with irradiated MI after different periods (2.6 and 30 days, three years) after ultraviolet irradiation have been studied. It is established that MI irradiation at a dose of 306J/m/sup 2/ doesn't result in its loss in postradiation generations however in posterity MI considerable ultrastructural changes occur. In two days after operation the shell of descendant MI of irradiated Paramecium bursaria forms multiple blades; small chromatin blocks considerably increase in sizes and, as a rule, occupy the central position in a nucleus. During later periods after irradiation (6 days) density of chromatin elements in MI begins to change. By the 30th day in MI fine-fibrillar karyoplasm detected are only not numerous chromatin structures scattered in disorder. The results obtained point to the existence of the ''cryptic'' type MIs are not revealed at the light-optical level but preserved in a series of postradiation generations. The presence of such MIs in viable cultures of P. bursaria confirms indirectly MI significance in vegetatic life of P. bursaria.

  20. Method and apparatus for processing algae

    Science.gov (United States)

    Chew, Geoffrey; Reich, Alton J.; Dykes, Jr., H. Waite; Di Salvo, Roberto

    2012-07-03

    Methods and apparatus for processing algae are described in which a hydrophilic ionic liquid is used to lyse algae cells. The lysate separates into at least two layers including a lipid-containing hydrophobic layer and an ionic liquid-containing hydrophilic layer. A salt or salt solution may be used to remove water from the ionic liquid-containing layer before the ionic liquid is reused. The used salt may also be dried and/or concentrated and reused. The method can operate at relatively low lysis, processing, and recycling temperatures, which minimizes the environmental impact of algae processing while providing reusable biofuels and other useful products.

  1. Errors When Extracting Oil from Algae

    Science.gov (United States)

    Murphy, E.; Treat, R.; Ichiuji, T.

    2014-12-01

    Oil is in popular demand, but the worldwide amount of oil is decreasing and prices for it are steadily increasing. Leading scientists have been working to find a solution of attaining oil in an economically and environmentally friendly way. Researchers at the U.S. Department of Energy's Pacific Northwest National Laboratory (PNNL) have determined that "a small mixture of algae and water can be turned into crude oil in less than an hour" (Sheehan, Duhahay, Benemann, Poessler). There are various ways of growing the algae, such as closed loop and open loop methods, as well as processes of extracting oil, such as hydrothermal liquefaction and the hexane-solvent method. Our objective was to grow the algae (C. reinhardtii) and extract oil from it using NaOH and HCl, because we had easy access to those specific chemicals. After two trials of attempted algae growth, we discovered that a bacteria was killing off the algae. This led us to further contemplation on how this dead algae and bacteria are affecting our environment, and the organisms within it. Eutrophication occurs when excess nutrients stimulate rapid growth of algae in an aquatic environment. This can clog waterways and create algal blooms in blue-green algae, as well as neurotoxic red tide phytoplankton. These microscopic algae die upon consumption of the nutrients in water and are degraded by bacteria. The bacteria respires and creates an acidic environment with the spontaneous conversion of carbon dioxide to carbonic acid in water. This process of degradation is exactly what occurred in our 250 mL flask. When the phytoplankton attacked our algae, it created a hypoxic environment, which eliminated any remaining amounts of oxygen, carbon dioxide, and nutrients in the water, resulting in a miniature dead zone. These dead zones can occur almost anywhere where there are algae and bacteria, such as the ocean, and make it extremely difficult for any organism to survive. This experiment helped us realize the

  2. 21 CFR 73.275 - Dried algae meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Dried algae meal. 73.275 Section 73.275 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.275 Dried algae meal. (a) Identity. The color additive dried algae meal is a dried mixture of algae cells (genus Spongiococcum, separated from its culture broth...

  3. 21 CFR 73.185 - Haematococcus algae meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Haematococcus algae meal. 73.185 Section 73.185... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and dried cells of the alga...

  4. Algae: putting carbon dioxide in a bind

    Energy Technology Data Exchange (ETDEWEB)

    Ewers, J.; Wiechers, G. [RWE Power (Germany)

    2009-03-15

    German utility RWE Power has initiated a cutting edge project that is investigating the use of marine microalgae to capture carbon dioxide produced during lignite combustion. At its Niederaussem power plant, a pilot plant has been erected for the production of microalgae. Flue gas is withdrawn from the lignite-based power plant and transported through polyethylene pipes to the microalgae production plant. The CO{sub 2} in the flue gas is dissolved in the algae suspension and adsorbed by the algae for growth in photobioreactors, developed by Noragreen Projektmanagement GmbH. The photobioreactors which consist of clear plastic hoses, fixed in V shape to supports. The study is aiming to optimise the entire algae production process and subsequent conversion and use of the algae biomass produced. Uses being investigated include hydrothermal carbonization to obtain hydrocarbon products. 1 figs., 1 photo.

  5. The Biology of blue-green algae

    National Research Council Canada - National Science Library

    Carr, Nicholas G; Whitton, B. A

    1973-01-01

    .... Their important environmental roles, their part in nitrogen fixation and the biochemistry of phototrophic metabolism are some of the attractions of blue-geen algae to an increasing number of biologists...

  6. Collection, Isolation and Culture of Marine Algae.

    Science.gov (United States)

    James, Daniel E.

    1984-01-01

    Methods of collecting, isolating, and culturing microscopic and macroscopic marine algae are described. Three different culture media list of chemicals needed and procedures for preparing Erdschreiber's and Provasoli's E. S. media. (BC)

  7. 2011 Biomass Program Platform Peer Review: Algae

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Joyce [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    2012-02-01

    This document summarizes the recommendations and evaluations provided by an independent external panel of experts at the 2011 U.S. Department of Energy Biomass Program’s Algae Platform Review meeting.

  8. Dipeptides from the red alga Acanthopora spicifera

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S; De; Kamat, S

    An investigation of red alga Acanthophora spicifera afforded the known peptide, aurantiamide acetate and a new diastereoisomer of this dipeptide (dia-aurantiamide acetate). This is a first report of aurantiamide acetate from a marine source...

  9. Stochastic Forecasting of Algae Blooms in Lakes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peng; Tartakovsky, Daniel M.; Tartakovsky, Alexandre M.

    2013-01-03

    We consider a general framework to predict the development of harmful algal blooms (HABs) in a lake driven by uncertain parameters. To quantify the concentration uncertainty of those algae groups via their joint probabilistic density function (PDF), we explore an approach based on the Fokker-Planck equation. Our result is presented in an example where abundant nutrients contribute to the proliferation of cyanobacteria and other minor algae groups.

  10. Biogas production experimental research using algae.

    Science.gov (United States)

    Baltrėnas, Pranas; Misevičius, Antonas

    2015-01-01

    The current study is on the the use of macro-algae as feedstock for biogas production. Three types of macro-algae, Cladophora glomerata (CG), Chara fragilis (CF), and Spirogyra neglecta (SN), were chosen for this research. The experimental studies on biogas production were carried out with these algae in a batch bioreactor. In the bioreactor was maintained 35 ± 1°C temperature. The results showed that the most appropriate macro-algae for biogas production are Spirogyra neglecta (SN) and Cladophora glomerata (CG). The average amount of biogas obtained from the processing of SN - 0.23 m(3)/m(3)d, CG - 0.20 m(3)/m(3)d, and CF - 0.12 m(3)/m(3)d. Considering the concentration of methane obtained during the processing of SN and CG, which after eight days and until the end of the experiment exceeded 60%, it can be claimed that biogas produced using these algae is valuable. When processing CF, the concentration of methane reached the level of 50% only by the final day of the experiment, which indicates that this alga is less suitable for biogas production.

  11. Antioxidant Activity of Hawaiian Marine Algae

    Directory of Open Access Journals (Sweden)

    Anthony D. Wright

    2012-02-01

    Full Text Available Marine algae are known to contain a wide variety of bioactive compounds, many of which have commercial applications in pharmaceutical, medical, cosmetic, nutraceutical, food and agricultural industries. Natural antioxidants, found in many algae, are important bioactive compounds that play an important role against various diseases and ageing processes through protection of cells from oxidative damage. In this respect, relatively little is known about the bioactivity of Hawaiian algae that could be a potential natural source of such antioxidants. The total antioxidant activity of organic extracts of 37 algal samples, comprising of 30 species of Hawaiian algae from 27 different genera was determined. The activity was determined by employing the FRAP (Ferric Reducing Antioxidant Power assays. Of the algae tested, the extract of Turbinaria ornata was found to be the most active. Bioassay-guided fractionation of this extract led to the isolation of a variety of different carotenoids as the active principles. The major bioactive antioxidant compound was identified as the carotenoid fucoxanthin. These results show, for the first time, that numerous Hawaiian algae exhibit significant antioxidant activity, a property that could lead to their application in one of many useful healthcare or related products as well as in chemoprevention of a variety of diseases including cancer.

  12. Antioxidant activity of Hawaiian marine algae.

    Science.gov (United States)

    Kelman, Dovi; Posner, Ellen Kromkowski; McDermid, Karla J; Tabandera, Nicole K; Wright, Patrick R; Wright, Anthony D

    2012-02-01

    Marine algae are known to contain a wide variety of bioactive compounds, many of which have commercial applications in pharmaceutical, medical, cosmetic, nutraceutical, food and agricultural industries. Natural antioxidants, found in many algae, are important bioactive compounds that play an important role against various diseases and ageing processes through protection of cells from oxidative damage. In this respect, relatively little is known about the bioactivity of Hawaiian algae that could be a potential natural source of such antioxidants. The total antioxidant activity of organic extracts of 37 algal samples, comprising of 30 species of Hawaiian algae from 27 different genera was determined. The activity was determined by employing the FRAP (Ferric Reducing Antioxidant Power) assays. Of the algae tested, the extract of Turbinaria ornata was found to be the most active. Bioassay-guided fractionation of this extract led to the isolation of a variety of different carotenoids as the active principles. The major bioactive antioxidant compound was identified as the carotenoid fucoxanthin. These results show, for the first time, that numerous Hawaiian algae exhibit significant antioxidant activity, a property that could lead to their application in one of many useful healthcare or related products as well as in chemoprevention of a variety of diseases including cancer.

  13. Fluorescence Properties of Chlorella sp. Algae

    Directory of Open Access Journals (Sweden)

    Tibor Teplicky

    2017-01-01

    Full Text Available Water quality and its fast and reliable monitoring is the challenge of the future. Design of appropriate biosensors that would be capable of non-invasive identification of water pollution is an important prerequisite for such challenge. Chlorophylls are pigments, naturally presented in all plants that absorb light. The main forms of chlorophyll in algae are chlorophyll a and chlorophyll b, other pigments include xantophylls and beta-carotenes. Our aim was to characterize endogenous fluorescence of the Chlorella sp. algae, present naturally in drinking water. We recorded spatial, spectral and lifetime fluorescence distribution in the native algae. We noted that the fluorescence was evenly distributed in the algae cytosol, but lacked in the nucleus and reached maximum at 680-690 nm. Fluorescence decay of chlorella sp. was double-exponential, and clearly shorter than that of its isolated pigments. For the first time, fluorescence lifetime image of the algae is presented. Study of the fluorescence properties of algae is aimed at the improvement of water supply contamination detection and cleaning.

  14. BIOTESTAREA ŞI ESTIMAREA TOXICITĂŢII COMPUŞILOR METALOORAGNICI ASUPRA POPULAŢIEI DE PARAMECIUM CAUDATUM

    Directory of Open Access Journals (Sweden)

    Ion TODERAŞ

    2017-03-01

    Full Text Available În articol este studiată influenţa unor grupuri de substanţe metaloorganice asupra microorganismelor acvatice. Este utilizată metoda de biotestare toxicologică a compuşilor coordinativi CMT-28 şi CMA-18 asupra ciliatelor Paramecium caudatum Ehrnbg, în concentraţii de 100, 10, 1, 0,1, 0,01 uM/L, comparativ cu prototipul. Metoda de biotestare ne permite să formulăm rapid concluzii în plan comparat, evitând riscul unei erori înalte.Proprietăţile compuşilor metaloorganici au fost cercetate prin metoda diluărilor în serie, în mediul nutritiv lichid (1 gsoluţie nutritivă/1 l apă. În calitate de culturi de referinţă au fost folosite ciliatele Paramecium caudatm.Infuzoriile, ca obiecte de cercetare, sunt foarte comode, se reproduc destul de rapid, fiind cele mai convenabile test-obiecte pentru investigaţii în condiţii de laborator, în care factorul timp joacă un rol decesiv, inclusiv pentru elucidarea impac­tului unor factori abiotici (substanţelor metaloorganice asupra procesului de reproducere asexuată la Paramecium caudatum.Activitatea substanţelor a fost evaluată după caracterul toxicităţii preparatelor (LT50 şi LC50, iar activitatea ciliatelor a fost studiată după caracterul viabilităţii şi parametrii reproductivi (creşterea sau diminuarea efectivului numeric şi a ratei lor de reproducere.Toxicitatea acută (LT50 şi LC50 a compuşilor a fost cercetată conform recomandărilor metodice privind studierea toxicităţii generale a remediilor farmaceutice.LC50 (concentraţia letală, 50% – concentraţia care cauzează moartea a 50% din test-organisme într-o anumită perioadă de timp.LT50 (timpul letal, 50% – timpul în care concentraţia utilizată a compusului testat cauzează moartea a 50% din organismele testate.THE BIOASSAY AND ESTIMATION OF THE TOXICITY OF METALLOORGANIC COMPOUNDS IMPACTING THE POPULATION OF PARAMECIUM CAUDATUMThis work will focus on the study of groups of metalloorganic

  15. Pseudaeromonas paramecii sp. nov., isolated from the ciliate Paramecium caudatum and emendation of the genus Pseudaeromonas.

    Science.gov (United States)

    Akter, Sumi; Shin, Mann Kyoon

    2018-04-17

    A Gram-stain-negative, oxidase-negative and catalase-negative, motile, rod-shaped bacterial strain, designated PCS8 T , hosted by the ciliate Paramecium caudatum was investigated by using a polyphasic approach. Strain PCS8 T was observed to be able to grow at 12-44 °C (optimum, 36-37 °C), at pH 6.0-10.0 (optimum, 7.0) and in the presence of 0-3 % NaCl (optimum, 1-2 %). It could hydrolyse starch and aesculin and produce acid from d-sorbitol, myo-inositol, glycerol and l-rhamnose. The sequence similarity of the new isolate was 96.9 % with respect to Pseudaeromonas pectinilytica and 96.3 % with respect to Pseudaeromonas sharmana. Phylogenetically, strain PCS8 T falls within the cluster comprising the Pseudaeromonas species. The predominant cellular fatty acids of strain PCS8 T were C16 : 0 (35.8 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 35.1 %) and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c; 10.8 %). This novel strain also contained various fatty acids that are not detected in other members of the genus Pseudaeromonas, such as C16 : 0 3-OH, C18 : 1ω9c and summed feature 5 (C18 : 2ω6,9c and/or C18 : 0 ante). Strain PCS8 T contained ubiquinone-8 as the sole respiratory quinone and phosphatidylethanolamine and phosphatidylglycerol as major polar lipids. The G+C content of the genomic DNA of the type strain was 66.5 mol%. Based on the distinct phenotypic, phylogenetic, chemotaxonomic and G+C content results, strain PCS8 T represents a currently undescribed species within the genus Pseudaeromonas in the family Aeromonadaceae, for which we suggest the name Pseudaeromonas paramecii sp. nov. with the type strain PCS8 T (=KCTC 62038 T =JCM 32226 T ). An emended description of the genus Pseudaeromonas is also provided.

  16. Tolerance of ciliated protozoan Paramecium bursaria (Protozoa, Ciliophora) to ammonia and nitrites

    Science.gov (United States)

    Xu, Henglong; Song, Weibo; Lu, Lu; Alan, Warren

    2005-09-01

    The tolerance to ammonia and nitrites in freshwater ciliate Paramecium bursaria was measured in a conventional open system. The ciliate was exposed to different concentrations of ammonia and nitrites for 2h and 12h in order to determine the lethal concentrations. Linear regression analysis revealed that the 2h-LC50 value for ammonia was 95.94 mg/L and for nitrite 27.35 mg/L using probit scale method (with 95% confidence intervals). There was a linear correlation between the mortality probit scale and logarithmic concentration of ammonia which fit by a regression equation y=7.32 x 9.51 ( R 2=0.98; y, mortality probit scale; x, logarithmic concentration of ammonia), by which 2 h-LC50 value for ammonia was found to be 95.50 mg/L. A linear correlation between mortality probit scales and logarithmic concentration of nitrite is also followed the regression equation y=2.86 x+0.89 ( R 2=0.95; y, mortality probit scale; x, logarithmic concentration of nitrite). The regression analysis of toxicity curves showed that the linear correlation between exposed time of ammonia-N LC50 value and ammonia-N LC50 value followed the regression equation y=2 862.85 e -0.08 x ( R 2=0.95; y, duration of exposure to LC50 value; x, LC50 value), and that between exposed time of nitrite-N LC50 value and nitrite-N LC50 value followed the regression equation y=127.15 e -0.13 x ( R 2=0.91; y, exposed time of LC50 value; x, LC50 value). The results demonstrate that the tolerance to ammonia in P. bursaria is considerably higher than that of the larvae or juveniles of some metozoa, e.g. cultured prawns and oysters. In addition, ciliates, as bacterial predators, are likely to play a positive role in maintaining and improving water quality in aquatic environments with high-level ammonium, such as sewage treatment systems.

  17. Hyperspectral imaging of snow algae and green algae from aeroterrestrial habitats

    Science.gov (United States)

    Holzinger, Andreas; Allen, Michael C.; Deheyn, Dimitri D.

    2016-01-01

    Snow algae and green algae living in aeroterrestrial habitats are ideal obbjects to study adaptation to high light irradiation. Here, we used a detailed description of the spectral properties as a proxy for photo-acclimation/protection in snow algae (Chlamydomonas nivalis, Chlainomonas sp. and Chloromonas sp.) and charopyhte green algae (Zygnema sp., Zygogonium ericetorum and Klebsormidium crenulatum). The hyperspectral microscopic mapping and imaging technique allowed us to acquire total absorbance spectra of these microalgae in the waveband of 400-900 nm. Particularly in Chlamydomonas nivalis and Chlainomonas sp., a high absorbance in the wave band of 400-550 nm was observed, due to naturally occurring secondary carotenoids; in Chloromonas sp. and in the charopyhte algae this was missing, the latter being close relatives to land plants. To investigate if cellular water loss has an influence on the spectral properties, the cells were plasmolysed in sorbitol or desiccated at ambient air. While in snow algae, these treatments did not change the spectral properties, in the charopyhte algae the condensation of the cytoplasm and plastids increased the absorbance in the lower waveband of 400 – 500 nm. These changes might be ecologically relevant and photoprotective, as aeroterrestrial algae are naturally exposed to occasional water limitation, leading to desiccation, which are conditions usually occurring together with higher irradiation. PMID:27442511

  18. Hyperspectral imaging of snow algae and green algae from aeroterrestrial habitats.

    Science.gov (United States)

    Holzinger, Andreas; Allen, Michael C; Deheyn, Dimitri D

    2016-09-01

    Snow algae and green algae living in aeroterrestrial habitats are ideal objects to study adaptation to high light irradiation. Here, we used a detailed description of the spectral properties as a proxy for photo-acclimation/protection in snow algae (Chlamydomonas nivalis, Chlainomonas sp. and Chloromonas sp.) and charophyte green algae (Zygnema sp., Zygogonium ericetorum and Klebsormidium crenulatum). The hyperspectral microscopic mapping and imaging technique allowed us to acquire total absorption spectra of these microalgae in the waveband of 400-900nm. Particularly in Chlamydomonas nivalis and Chlainomonas sp., a high absorbance between 400-550nm was observed, due to naturally occurring secondary carotenoids; in Chloromonas sp. and in the charopyhte algae this high absorbance was missing, the latter being close relatives to land plants. To investigate if cellular water loss has an influence on the spectral properties, the cells were plasmolysed in sorbitol or desiccated at ambient air. While in snow algae, these treatments did hardly change the spectral properties, in the charopyhte algae the condensation of the cytoplasm and plastids increased the absorbance in the lower waveband of 400-500nm. These changes might be ecologically relevant and photoprotective, as aeroterrestrial algae are naturally exposed to occasional water limitation, leading to desiccation, which are conditions usually occurring together with higher irradiation. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Radiation sterilization of harmful algae in water

    International Nuclear Information System (INIS)

    Byung Chull An; Jae-Sung Kim; Seung Sik Lee; Shyamkumar Barampuram; Eun Mi Lee; Byung Yeoup Chung

    2007-01-01

    Complete text of publication follows. Objective: Drinking water, water used in food production and for irrigation, water for fish farming, waste water, surface water, and recreational water have been recently recognized as a vector for the transmission of harmful micro-organisms. The human and animal harmful algae is a waterborne risk to public health and economy because the algae are ubiquitous and persistent in water and wastewater, not completely removed by physical-chemical treatment processes, and relatively resistant to chemical disinfection. Gamma and electron beam radiation technology is of growing in the water industry since it was demonstrated that gamma and electron beam radiation is very effective against harmful algae. Materials and Methods: Harmful algae (Scenedesmus quadricauda(Turpin) Brebisson 1835 (AG10003), Chlorella vulgaris Beijerinck 1896 (AG30007) and Chlamydomonas sp. (AG10061)) were distributed from Korean collection for type cultures (KCTC). Strains were cultured aerobically in Allen's medium at 25□ and 300 umol/m2s for 1 week using bioreactor. We investigated the disinfection efficiency of harmful algae irradiated with gamma (0.05 to 10 kGy for 30 min) and electron beam (1 to 19 kGy for 5 sec) rays. Results and Conclusion: We investigated the disinfection efficiency of harmful algae irradiated with gamma and electron beam rays of 50 to 19000 Gy. We established the optimum sterilization condition which use the gamma and electron beam radiation. Gamma ray disinfected harmful algae at 400 Gy for 30 min. Also, electron beam disinfected at 1000 Gy for 5 sec. This alternative disinfection practice had powerful disinfection efficiency. Hence, the multi-barrier approach for drinking water treatment in which a combination of various disinfectants and filtration technologies are applied for removal and inactivation of different microbial pathogens will guarantee a lower risk of microbial contamination.

  20. Algae Biofuel in the Nigerian Energy Context

    Directory of Open Access Journals (Sweden)

    Elegbede Isa

    2016-05-01

    Full Text Available The issue of energy consumption is one of the issues that have significantly become recognized as an important topic of global discourse. Fossil fuels production reportedly experiencing a gradual depletion in the oil-producing nations of the world. Most studies have relatively focused on biofuel development and adoption, however, the awareness of a prospect in the commercial cultivation of algae having potential to create economic boost in Nigeria, inspired this research. This study aims at exploring the potential of the commercialization of a different but commonly found organism, algae, in Nigeria. Here, parameters such as; water quality, light, carbon, average temperature required for the growth of algae, and additional beneficial nutrients found in algae were analysed. A comparative cum qualitative review of analysis was used as the study made use of empirical findings on the work as well as the author’s deductions. The research explored the cultivation of algae with the two major seasonal differences (i.e. rainy and dry in Nigeria as a backdrop. The results indicated that there was no significant difference in the contribution of algae and other sources of biofuels as a necessity for bioenergy in Nigeria. However, for an effective sustainability of this prospect, adequate measures need to be put in place in form of funding, provision of an economically-enabling environment for the cultivation process as well as proper healthcare service in the face of possible health hazard from technological processes. Further studies can seek to expand on the potential of cultivating algae in the Harmattan season.

  1. Phylogenetic placement of two previously described intranuclear bacteria from the ciliate Paramecium bursaria (Protozoa, Ciliophora): 'Holospora acuminata' and 'Holospora curviuscula'.

    Science.gov (United States)

    Rautian, Maria S; Wackerow-Kouzova, Natalia D

    2013-05-01

    'Holospora acuminata' infects micronuclei of Paramecium bursaria (Protozoa, Ciliophora), whereas 'Holospora curviuscula' infects the macronucleus in other clones of the same host species. Because these micro-organisms have not been cultivated, their description has been based only on some morphological properties and host and nuclear specificities. One16S rRNA gene sequence of 'H. curviuscula' is present in databases. The systematic position of the representative strain of 'H. curviuscula', strain MC-3, was determined in this study. Moreover, for the first time, two strains of 'H. acuminata', KBN10-1 and AC61-10, were investigated. Phylogenetic analysis indicated that all three strains belonged to the genus Holospora, family Holosporaceae, order Rickettsiales within the Alphaproteobacteria.

  2. X-ray microanalysis in cryosections of natively frozen Paramecium caudatum with regard to ion distribution in ciliates

    International Nuclear Information System (INIS)

    Schmitz, M.; Meyer, R.; Zierold, K.

    1985-01-01

    Cells of Paramecium caudatum were shock-frozen without pretreatment for cryoultramicrotomy and freeze-dried for subsequent X-ray microanalysis. Na, Mg, P, S, Cl, K, and Ca were detected in different amounts in several subcellular compartments. In particular, calcium was localized below the cell surface (pellicle). Trichocysts were found to contain significant amounts of Na in their base but not in the tip. Na, Mg, P, S, Cl, K, Ca were found in electron dense deposits within the lumen of the contractile vacuole. A small K concentration was found in the cytoplasm and in the mitochondria. X-ray microanalysis of the element distribution in different subcellular compartments provides information for the understanding of cellular functions such as exocytosis, locomotion, and ion regulation

  3. Molecular Identification of Paramecium bursaria Syngens and Studies on Geographic Distribution using Mitochondrial Cytochrome C Oxidase Subunit I (COI).

    Science.gov (United States)

    Zagata, Patrycja; Greczek-Stachura, Magdalena; Tarcz, Sebastian; Rautian, Maria

    2015-01-01

    Paramecium bursaria is composed of five syngens that are morphologically indistinguishable but sexually isolated. The aim of the present study was to confirm by molecular methods (analyses of mitochondrial COI) the identification of P. bursaria syngens originating from different geographical locations. Phylograms constructed using both the neighbor-joining and maximum-likelihood methods based on a comparison of 34 sequences of P. bursaria strains and P. multimicronucleatum, P. caudatum and P.calkinsi strains used as outgroups revealed five clusters which correspond to results obtained previously by mating reaction. Our analysis shows the existence of 24 haplotypes for the COI gene sequence in the studied strains. The interspecies haplotype diversity was Hd = 0.967. We confirmed genetic differentiation between strains of P. bursaria and the occurrence of a correlation between geographical distribution and the correspondent syngen.

  4. Investigation of the effect of biologically active threo-Ds-isocitric acid on oxidative stress in Paramecium caudatum.

    Science.gov (United States)

    Morgunov, Igor G; Karpukhina, Olga V; Kamzolova, Svetlana V; Samoilenko, Vladimir A; Inozemtsev, Anatoly N

    2018-01-02

    The effect of biologically active form (threo-Ds-) of isocitric acid (ICA) on oxidative stress was studied using the infusorian Paramecium caudatum stressed by hydrogen peroxide and salts of some heavy metals (Cu, Pb, Zn, and Cd). ICA at concentrations between 0.5 and 10 mM favorably influenced the infusorian cells with oxidative stress induced by the toxicants studied. The maximal antioxidant effect of ICA was observed at its concentration 10 mM irrespective of the toxicant used (either H 2 O 2 or heavy metal ions). ICA was found to be a more active antioxidant than ascorbic acid. Biologically active pharmaceutically pure threo-Ds-ICA was produced through cultivation of the yeast Yarrowia lipolytica and isolated from the culture liquid in the form of crystalline monopotassium salt with a purity of 99.9%.

  5. X-ray microanalysis in cryosections of natively frozen Paramecium caudatum with regard to ion distribution in ciliates

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, M.; Meyer, R.; Zierold, K.

    1985-01-01

    Cells of Paramecium caudatum were shock-frozen without pretreatment for cryoultramicrotomy and freeze-dried for subsequent X-ray microanalysis. Na, Mg, P, S, Cl, K, and Ca were detected in different amounts in several subcellular compartments. In particular, calcium was localized below the cell surface (pellicle). Trichocysts were found to contain significant amounts of Na in their base but not in the tip. Na, Mg, P, S, Cl, K, Ca were found in electron dense deposits within the lumen of the contractile vacuole. A small K concentration was found in the cytoplasm and in the mitochondria. X-ray microanalysis of the element distribution in different subcellular compartments provides information for the understanding of cellular functions such as exocytosis, locomotion, and ion regulation.

  6. Sustainable Algae Biodiesel Production in Cold Climates

    Directory of Open Access Journals (Sweden)

    Rudras Baliga

    2010-01-01

    Full Text Available This life cycle assessment aims to determine the most suitable operating conditions for algae biodiesel production in cold climates to minimize energy consumption and environmental impacts. Two hypothetical photobioreactor algae production and biodiesel plants located in Upstate New York (USA are modeled. The photobioreactor is assumed to be housed within a greenhouse that is located adjacent to a fossil fuel or biomass power plant that can supply waste heat and flue gas containing CO2 as a primary source of carbon. Model results show that the biodiesel areal productivity is high (19 to 25 L of BD/m2/yr. The total life cycle energy consumption was between 15 and 23 MJ/L of algae BD and 20 MJ/L of soy BD. Energy consumption and air emissions for algae biodiesel are substantially lower than soy biodiesel when waste heat was utilized. Algae's most substantial contribution is a significant decrease in the petroleum consumed to make the fuel.

  7. Biological toxicity of lanthanide elements on algae.

    Science.gov (United States)

    Tai, Peidong; Zhao, Qing; Su, Dan; Li, Peijun; Stagnitti, Frank

    2010-08-01

    The biological toxicity of lanthanides on marine monocellular algae was investigated. The specific objective of this research was to establish the relationship between the abundance in the seawater of lanthanides and their biological toxicities on marine monocellular algae. The results showed that all single lanthanides had similar toxic effects on Skeletonema costatum. High concentrations of lanthanides (29.04+/-0.61 micromol L(-1)) resulted in 50% reduction in growth of algae compared to the controls (0 micromol L(-1)) after 96 h (96 h-EC50). The biological toxicity of 13 lanthanides on marine monocellular algae was unrelated with the abundance of different lanthanide elements in nature, and the "Harkins rule" was not appropriate for the lanthanides. A mixed solution that contained equivalent concentrations of each lanthanide element had the same inhibition effect on algae cells as each individual lanthanide element at the same total concentration. This phenomenon is unique compared to the groups of other elements in the periodic table. Hence, we speculate that the monocellular organisms might not be able to sufficiently differentiate between the almost chemically identical lanthanide elements. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  8. Phospholipids of New Zealand Edible Brown Algae.

    Science.gov (United States)

    Vyssotski, Mikhail; Lagutin, Kirill; MacKenzie, Andrew; Mitchell, Kevin; Scott, Dawn

    2017-07-01

    Edible brown algae have attracted interest as a source of beneficial allenic carotenoid fucoxanthin, and glyco- and phospholipids enriched in polyunsaturated fatty acids. Unlike green algae, brown algae contain no or little phosphatidylserine, possessing an unusual aminophospholipid, phosphatidyl-O-[N-(2-hydroxyethyl) glycine], PHEG, instead. When our routinely used technique of 31 P-NMR analysis of phospholipids was applied to the samples of edible New Zealand brown algae, a number of signals corresponding to unidentified phosphorus-containing compounds were observed in total lipids. NI (negative ion) ESI QToF MS spectra confirmed the presence of more familiar phospholipids, and also suggested the presence of PHEG or its isomers. The structure of PHEG was confirmed by comparison with a synthetic standard. An unusual MS fragmentation pattern that was also observed prompted us to synthesise a number of possible candidates, and was found to follow that of phosphatidylhydroxyethyl methylcarbamate, likely an extraction artefact. An unexpected outcome was the finding of ceramidephosphoinositol that has not been reported previously as occurring in brown algae. An uncommon arsenic-containing phospholipid has also been observed and quantified, and its TLC behaviour studied, along with that of the newly synthesised lipids.

  9. Effect of ferrate on green algae removal.

    Science.gov (United States)

    Kubiňáková, Emília; Híveš, Ján; Gál, Miroslav; Fašková, Andrea

    2017-09-01

    Green algae Cladophora aegagropila, present in cooling water of thermal power plants, causes many problems and complications, especially during summer. However, algae and its metabolites are rarely eliminated by common removal methods. In this work, the elimination efficiency of electrochemically prepared potassium ferrate(VI) on algae from cooling water was investigated. The influence of experimental parameters, such as Fe(VI) dosage, application time, pH of the system, temperature and hydrodynamics of the solution on removal efficiency, was optimized. This study demonstrates that algae C. aegagropila can be effectively removed from cooling water by ferrate. Application of ferrate(VI) at the optimized dosage and under the suitable conditions (temperature, pH) leads to 100% removal of green algae Cladophora from the system. Environmentally friendly reduction products (Fe(III)) and coagulation properties favour the application of ferrate for the treatment of water contaminated with studied microorganisms compared to other methods such as chlorination and use of permanganate, where harmful products are produced.

  10. Radiation effects on algae and its application

    International Nuclear Information System (INIS)

    Dwivedi, Rakesh Kumar

    2013-01-01

    The effects of radiation on algae have been summarized in this article. Today, algae are being considered to have the great potential to fulfill the demand of food, fodder, fuel and various pharmaceutical products. Red algae are particularly rich in the content of polysaccharides present in their cell wall. For isolation of these polysaccharides, separation of cells cemented together by middle lamella is essential. The gamma rays are known to bring about biochemical changes in the cell wall and cause the breakdown of the middle lamella. These rays ate also known to speed up the starch sugar inter-conversion in the cells which is very useful for the tapping the potential of algae to be used as biofuel as well as in pharmaceutical industries. Cyanobacteria, among algae and other plants are more resistant to the radiation. In some cyanobacteria the radiation treatment is known to enhance the resistance against the antibiotics. Radiation treatment is also known to enhance the diameter of cell and size of the nitrogen fixing heterocyst. (author)

  11. Controlled regular locomotion of algae cell microrobots.

    Science.gov (United States)

    Xie, Shuangxi; Jiao, Niandong; Tung, Steve; Liu, Lianqing

    2016-06-01

    Algae cells can be considered as microrobots from the perspective of engineering. These organisms not only have a strong reproductive ability but can also sense the environment, harvest energy from the surroundings, and swim very efficiently, accommodating all these functions in a body of size on the order of dozens of micrometers. An interesting topic with respect to random swimming motions of algae cells in a liquid is how to precisely control them as microrobots such that they swim according to manually set routes. This study developed an ingenious method to steer swimming cells based on the phototaxis. The method used a varying light signal to direct the motion of the cells. The swimming trajectory, speed, and force of algae cells were analyzed in detail. Then the algae cell could be controlled to swim back and forth, and traverse a crossroad as a microrobot obeying specific traffic rules. Furthermore, their motions along arbitrarily set trajectories such as zigzag, and triangle were realized successfully under optical control. Robotize algae cells can be used to precisely transport and deliver cargo such as drug particles in microfluidic chip for biomedical treatment and pharmacodynamic analysis. The study findings are expected to bring significant breakthrough in biological drives and new biomedical applications.

  12. Effect of wortmannin and phorbol ester on Paramecium fluid-phase uptake in the presence of transferrin.

    Science.gov (United States)

    Wiejak, J; Surmacz, L; Wyroba, E

    2001-01-01

    The kinetics of the uptake of the fluid phase marker Lucifer Yellow (LY), and its alteration by wortmannin, an inhibitor of phosphatidylinositol-3 kinase (PI-3K), and the PKC modulators: GF 109203 X, an inhibitor, and phorbol ester, an activator was studied in eukaryotic model Paramecium aurelia. Spectrophotometric quantification of LY accumulation was performed in the presence or absence of transferrin, a marker of receptor-mediated endocytosis. Internalization of LY showed a curvilinear kinetics: the high initial rate of LY uptake (575 ng LY/mg protein/hr) decreased almost 5-fold within 15 min, reaching plateau at 126 ng/mg protein/hr. Transferrin induced a small increase (7.5%) in the fluid phase uptake rate (after 5 min) followed by a small decrease at longer incubation times. Lucifer Yellow and transferrin (visualized by streptavidin-FITC) were localized in Paramecium by 3-D reconstruction by confocal microscopy. LY showed a scattered, diffuse fluorescence typical of fluid phase uptake whereas transferrin accumulated in membrane-surrounded endosomes. Wortmannin did not affect LY accumulation but decreased it when transferrin was present in the incubation medium. This suggests an effect on the transferrin uptake pathway, presumably on the stage of internalization in "mixing" endosomes to which transferrin and LY were targeted. Phorbol ester diminished LY accumulation by 22% and this effect persisted up to 25 min of incubation. PKC inhibitor did not affect LY uptake. However, in the presence of transferrin, the LY uptake increased within the first 15 minutes followed by a rapid 20% decrease in comparison to the control. Such an effect of PKC modulators suggests that PMA action on fluid phase uptake is not directly mediated by PKC.

  13. Early stages of functional diversification in the Rab GTPase gene family revealed by genomic and localization studies in Paramecium species.

    Science.gov (United States)

    Bright, Lydia J; Gout, Jean-Francois; Lynch, Michael

    2017-04-15

    New gene functions arise within existing gene families as a result of gene duplication and subsequent diversification. To gain insight into the steps that led to the functional diversification of paralogues, we tracked duplicate retention patterns, expression-level divergence, and subcellular markers of functional diversification in the Rab GTPase gene family in three Paramecium aurelia species. After whole-genome duplication, Rab GTPase duplicates are more highly retained than other genes in the genome but appear to be diverging more rapidly in expression levels, consistent with early steps in functional diversification. However, by localizing specific Rab proteins in Paramecium cells, we found that paralogues from the two most recent whole-genome duplications had virtually identical localization patterns, and that less closely related paralogues showed evidence of both conservation and diversification. The functionally conserved paralogues appear to target to compartments associated with both endocytic and phagocytic recycling functions, confirming evolutionary and functional links between the two pathways in a divergent eukaryotic lineage. Because the functionally diversifying paralogues are still closely related to and derived from a clade of functionally conserved Rab11 genes, we were able to pinpoint three specific amino acid residues that may be driving the change in the localization and thus the function in these proteins. © 2017 Bright et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  14. Flow cytometry sorting of nuclei enables the first global characterization of Paramecium germline DNA and transposable elements.

    Science.gov (United States)

    Guérin, Frédéric; Arnaiz, Olivier; Boggetto, Nicole; Denby Wilkes, Cyril; Meyer, Eric; Sperling, Linda; Duharcourt, Sandra

    2017-04-26

    DNA elimination is developmentally programmed in a wide variety of eukaryotes, including unicellular ciliates, and leads to the generation of distinct germline and somatic genomes. The ciliate Paramecium tetraurelia harbors two types of nuclei with different functions and genome structures. The transcriptionally inactive micronucleus contains the complete germline genome, while the somatic macronucleus contains a reduced genome streamlined for gene expression. During development of the somatic macronucleus, the germline genome undergoes massive and reproducible DNA elimination events. Availability of both the somatic and germline genomes is essential to examine the genome changes that occur during programmed DNA elimination and ultimately decipher the mechanisms underlying the specific removal of germline-limited sequences. We developed a novel experimental approach that uses flow cell imaging and flow cytometry to sort subpopulations of nuclei to high purity. We sorted vegetative micronuclei and macronuclei during development of P. tetraurelia. We validated the method by flow cell imaging and by high throughput DNA sequencing. Our work establishes the proof of principle that developing somatic macronuclei can be sorted from a complex biological sample to high purity based on their size, shape and DNA content. This method enabled us to sequence, for the first time, the germline DNA from pure micronuclei and to identify novel transposable elements. Sequencing the germline DNA confirms that the Pgm domesticated transposase is required for the excision of all ~45,000 Internal Eliminated Sequences. Comparison of the germline DNA and unrearranged DNA obtained from PGM-silenced cells reveals that the latter does not provide a faithful representation of the germline genome. We developed a flow cytometry-based method to purify P. tetraurelia nuclei to high purity and provided quality control with flow cell imaging and high throughput DNA sequencing. We identified 61

  15. Effect of wortmannin and phorbol ester on Paramecium fluid-phase uptake in the presence of transferrin

    Directory of Open Access Journals (Sweden)

    J Wiejak

    2009-12-01

    Full Text Available The kinetics of the uptake of the fluid phase marker Lucifer Yellow (LY, and its alteration by wortmannin, an inhibitor of phosphatidylinositol-3 kinase (PI-3K, and the PKC modulators: GF 109203 X, an inhibitor, and phorbol ester, an activator was studied in eukaryotic model Paramecium aurelia. Spectrophotometric quantification of LY accumulation was performed in the presence or absence of transferrin, a marker of receptor-mediated endocytosis. Internalization of LY showed a curvilinear kinetics: the high initial rate of LYuptake (575 ng LY/ mg protein /hr decreased almost 5-fold within 15 min, reaching plateau at 126 ng/ mg protein /hr. Transferrin induced a small increase (7.5% in the fluid phase uptake rate (after 5 min followed by a small decrease at longer incubation times. Lucifer Yellow and transferrin (visualized by streptavidin– FITC were localized in Paramecium by 3-D reconstruction by confocal microscopy. LY showed a scattered, diffuse fluorescence typical of fluid phase uptake whereas transferrin accumulated in membrane-surrounded endosomes. Wortmannin did not affect LY accumulation but decreased it when transferrin was present in the incubation medium. This suggests an effect on the transferrin uptake pathway, presumably on the stage of internalization in “mixing” endosomes to which transferrin and LY were targeted. Phorbol ester diminished LY accumulation by 22% and this effect persisted up to 25 min of incubation. PKC inhibitor did not affect LY uptake. However, in the presence of transferrin, the LY uptake increased within the first 15 minutes followed by a rapid 20% decrease in comparison to the control. Such an effect of PKC modulators suggests that PMA action on fluid phase uptake is not directly mediated by PKC.

  16. Freshwater algae of the Nevada Test Site

    International Nuclear Information System (INIS)

    Taylor, W.D.; Giles, K.R.

    1979-06-01

    Fifty-two species of freshwater algae were identified in samples collected from the eight known natural springs of the Nevada Test Site. Although several species were widespread, 29 species were site specific. Diatoms provided the greatest variety of species at each spring. Three-fifths of all algal species encountered were diatoms. Well-developed mats of filamentous green algae (Chlorophyta) were common in many of the water tanks associated with the springs and accounted for most of the algal biomass. Major nutrients were adequate, if not abundant, in most spring waters - growth being limited primarily by light and physical habitat. There was some evidence of cesium-137 bioconcentration by algae at several of the springs

  17. Freshwater algae of the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, W.D.; Giles, K.R.

    1979-06-01

    Fifty-two species of freshwater algae were identified in samples collected from the eight known natural springs of the Nevada Test Site. Although several species were widespread, 29 species were site specific. Diatoms provided the greatest variety of species at each spring. Three-fifths of all algal species encountered were diatoms. Well-developed mats of filamentous green algae (Chlorophyta) were common in many of the water tanks associated with the springs and accounted for most of the algal biomass. Major nutrients were adequate, if not abundant, in most spring waters - growth being limited primarily by light and physical habitat. There was some evidence of cesium-137 bioconcentration by algae at several of the springs.

  18. Behaviour of technetium in marine algae

    International Nuclear Information System (INIS)

    Bonotto, S.; Kirchmann, R.; Van Baelen, J.; Hurtger, C.; Cogneau, M.; Van der Ben, D.; Verthe, C.; Bouquegneau, J.M.

    1985-01-01

    Uptake and distribution of technetium were studied in several green (Acetabularia acetabulum, Boergesenia forbesii, Ulva lactuca) and brown (Ascophyllum nodosum, Fucus serratus, Fucus spiralis and Fucus vesiculosus) marine algae. Technetium was supplied to the algae as Tc-95m-pertechnetate. Under laboratory conditions, the algae were capable of accumulating technetium, with the exception, however, of Boergesenia, which showed concentration factors (C.F.) comprised between 0.28 and 0.71. The concentration of technetium-99 in Fucus spiralis, collected along the Belgian coast, was measured by a radiochemical procedure. The intracellular distribution of technetium was studied by differential centrifugation in Acetabularia and by the puncturing technique in Boergesenia. The chemical forms of technetium penetrated into the cells were investigated by selective chemical extractions, molecular sieving and thin layer chromatography

  19. Behaviour of technetium in marine algae

    International Nuclear Information System (INIS)

    Bonotto, S.; Kirchmann, R.; Baelen, J. van; Hurtgen, C.; Cogneau, M.; Ben, D. van der; Verthe, C.; Bouquegneau, J.M.

    1986-01-01

    Uptake and distribution of technetium were studied in several green (Acetabularia acetabulum, Boergesenia forbesii, Ulva lactuca) and brown (Ascophyllum nodosum, Fucus serratus, Fucus spiralis and Fucus vesiculosus) marine algae. Technetium was supplied to the algae as Tc-95-pertechnetate. Under laboratory conditions, the algae were capable of accumulating technetium, with the exception, however, of Boergesenia, which showed concentration factors (C.F.) comprised between 0.28 and 0.71. The concentration of technetium-99 in Fucus spiralis, collected along the Belgian coast, was measured by a radiochemical procedure. The intracellular distribution of technetium was studied by differential centrifugation in Acetabularia and by the puncturing technique in Boergesenia. The chemical forms of technetium penetrated into the cells were investigated by selective chemical extractions, molecular sieving and thin layer chromatography. (author)

  20. Study of metal bioaccumulation by nuclear microprobe analysis of algae fossils and living algae cells

    International Nuclear Information System (INIS)

    Guo, P.; Wang, J.; Li, X.; Zhu, J.; Reinert, T.; Heitmann, J.; Spemann, D.; Vogt, J.; Flagmeyer, R.-H.; Butz, T.

    2000-01-01

    Microscopic ion-beam analysis of palaeo-algae fossils and living green algae cells have been performed to study the metal bioaccumulation processes. The algae fossils, both single cellular and multicellular, are from the late Neoproterozonic (570 million years ago) ocean and perfectly preserved within a phosphorite formation. The biosorption of the rare earth element ions Nd 3+ by the green algae species euglena gracilis was investigated with a comparison between the normal cells and immobilized ones. The new Leipzig Nanoprobe, LIPSION, was used to produce a proton beam with 2 μm size and 0.5 nA beam current for this study. PIXE and RBS techniques were used for analysis and imaging. The observation of small metal rich spores (<10 μm) surrounding both of the fossils and the living cells proved the existence of some specific receptor sites which bind metal carrier ligands at the microbic surface. The bioaccumulation efficiency of neodymium by the algae cells was 10 times higher for immobilized algae cells. It confirms the fact that the algae immobilization is an useful technique to improve its metal bioaccumulation

  1. Modeling and optimization of algae growth

    OpenAIRE

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savceno, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runo water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a variety of applications including production of bio-diesel, animal feed, products for pharmaceutical and cosmetic purposes, or it can even be used as a source of heating or electricity. The aim of t...

  2. Modeling and optimization of algae growth

    OpenAIRE

    Thornton, A; Weinhart, T; Bokhove, O; Zhang, B; Sar, van der, DM; Kumar, K Kundan; Pisarenco, M Maxim; Rudnaya, M Maria; Savcenco, V Valeriu; Rademacher, JDM; Zijlstra, J; Szabelska, A; Zyprych, J; Schans, van der, M Martin; Timperio, V

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runoff water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a variety of applications including production of bio-diesel, animal feed, products for pharmaceutical and cosmetic purposes, or it can even be used as a source of heating or electricity . The aim o...

  3. Serpins in plants and green algae

    DEFF Research Database (Denmark)

    Roberts, Thomas Hugh; Hejgaard, Jørn

    2008-01-01

    . Serpins have been found in diverse species of the plant kingdom and represent a distinct clade among serpins in multicellular organisms. Serpins are also found in green algae, but the evolutionary relationship between these serpins and those of plants remains unknown. Plant serpins are potent inhibitors...... of mammalian serine proteinases of the chymotrypsin family in vitro but, intriguingly, plants and green algae lack endogenous members of this proteinase family, the most common targets for animal serpins. An Arabidopsis serpin with a conserved reactive centre is now known to be capable of inhibiting...

  4. [Comparative chemical composition of the Barents Sea brown algae].

    Science.gov (United States)

    Obluchinskaia, E D

    2008-01-01

    Comparative study of phytochemical compositions of the most widespread brown algae species (one laminarian and four fucoid algae) from Barents Sea has been performed. A modified technique for mannitol determination in brown algae is proposed. It was revealed that fucus algae (fam. Fucaceae) contain 3% (of total dry weight) less mannitol than laminaria (Laminaria saccharina). The contents of alginic acid and laminaran in the Barents Sea fucoids are more than 10% less compared to laminaria. The alga L. saccharina contains almost two times more iodine than the species of fam. Fucaceae. The amounts of fucoidan and sum lipids in the Barents Sea fucoid algae is higher than in Laminaria saccharina (4-7% and 1-3%, respectively). In terms of contents of main biologically active compounds, fucus and laminarian algae from Barents Sea are inferior to none of the Far-Eastern species. The Barents Sea algae may become an important source of biologically active compounds.

  5. Use of Brown Algae to Demonstrate Natural Products Techniques.

    Science.gov (United States)

    Porter, Lee A.

    1985-01-01

    Background information is provided on the natural products found in marine organisms in general and the brown algae in particular. Also provided are the procedures needed to isolate D-mannitol (a primary metabolite) and cholesterol from brown algae. (JN)

  6. WASP7 BENTHIC ALGAE - MODEL THEORY AND USER'S GUIDE

    Science.gov (United States)

    The standard WASP7 eutrophication module includes nitrogen and phosphorus cycling, dissolved oxygen-organic matter interactions, and phytoplankton kinetics. In many shallow streams and rivers, however, the attached algae (benthic algae, or periphyton, attached to submerged substr...

  7. Association of thraustochytrids and fungi with living marine algae

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Nagarkar, S.; Raghukumar, S.

    only in C. clavulatum, Sargassum cinereum and Padina tetrastromatica whilst mycelial fungi occurred in all. Growth experiments in the laboratory indicated that the growth of thraustochytrids was inhibited on live algae, whereas killed algae supported...

  8. An Overview of Algae Biofuel Production and Potential Environmental Impact

    Science.gov (United States)

    Algae are among the most potentially significant sources of sustainable biofuels in the future of renewable energy. A feedstock with virtually unlimited applicability, algae can metabolize various waste streams (e.g., municipal wastewater, carbon dioxide from industrial flue gas)...

  9. Harmful impact of filamentous algae (Spirogyra sp.) on juvenile crayfish

    OpenAIRE

    Ulikowski Dariusz; Chybowski Łucjan; Traczuk Piotr

    2015-01-01

    The aim of this study was to determine the impact of filamentous algae on the growth and survival of juvenile narrow-clawed crayfish, Astacus leptodactylus (Esch.), in rearing basins. Three stocking variants were used: A - basins with a layer of filamentous algae without imitation mineral substrate; B - basins with a layer of filamentous algae with imitation mineral substrate; C - basins without filamentous algae but with mineral substrate. The crayfish were reared from June 12 to October 10 ...

  10. KAROTENOID PADA ALGAE: KAJIAN TENTANG BIOSINTESIS, DISTRIBUSI SERTA FUNGSI KAROTENOID

    OpenAIRE

    Merdekawati, Windu; Karwur, Ferry F.; Susanto, A. B.

    2017-01-01

    ABSTRAK   Karotenoid terdistribusi pada archaea, bakteri, jamur, tumbuhan, hewan serta algae. Karotenoid dihasilkan dari komponen isopentenyl pyrophosphate (IPP) yang mengalami proses secara bertahap untuk membentuk beragam jenis karotenoid. Terdapat dua kelompok karotenoid yaitu karoten dan xantofil dengan berbagai jenis turunannya. Struktur kimia pada karotenoid algae yaitu allene, acetylene serta acetylated carotenoids. Algae mempunyai karotenoid spesifik yang menarik untuk dipe...

  11. Relationships between algae taxa and physico-chemical ...

    African Journals Online (AJOL)

    A study of algae flora was performed on 16 samples collected in different aquatic environments in Bamenda (Cameroon) in order to evidence the relationships between algae assemblages and physico-chemical parameters of the milieu. A total of 22 algae species were identified, the most represented class being ...

  12. Composition of phytoplankton algae in Gubi Reservoir, Bauchi ...

    African Journals Online (AJOL)

    Studies on the distribution, abundance and taxonomic composition of phytoplankton algae in Gubi reservoir were carried out for 12 months (from January to December 1995). Of the 26 algal taxa identified, 14 taxa belonged to the diatoms, 8 taxa were green algae while 4 taxa belonged to the blue-green algae. Higher cell ...

  13. Can the primary algae production be measured precisely?

    International Nuclear Information System (INIS)

    Olesen, M.; Lundsgaard, C.

    1996-01-01

    Algae production in seawater is extremely important as a basic link in marine food chains. Evaluation of the algae quantity is based on 14CO 2 tracer techniques while natural circulation and light absorption in seawater is taken insufficiently into account. Algae production can vary by 500% in similar nourishment conditions, but varying water mixing conditions. (EG)

  14. Inventory of North-West European algae initiatives

    NARCIS (Netherlands)

    Spruijt, J.

    2015-01-01

    In 2012 an inventory of North-West European (NWE) algae initiatives was carried out to get an impression of the market and research activities on algae production and refinery, especially for bioenergy purposes. A questionnaire was developed that would provide the EnAlgae project with information on

  15. How to Identify and Control Water Weeds and Algae.

    Science.gov (United States)

    Applied Biochemists, Inc., Mequon, WI.

    Included in this guide to water management are general descriptions of algae, toxic algae, weed problems in lakes, ponds, and canals, and general discussions of mechanical, biological and chemical control methods. In addition, pictures, descriptions, and recommended control methods are given for algae, 6 types of floating weeds, 18 types of…

  16. New methodologies for integrating algae with CO2 capture

    NARCIS (Netherlands)

    Hernandez Mireles, I.; Stel, R.W. van der; Goetheer, E.L.V.

    2014-01-01

    It is generally recognized, that algae could be an interesting option for reducing CO2 emissions. Based on light and CO2, algae can be used for the production various economically interesting products. Current algae cultivation techniques, however, still present a number of limitations. Efficient

  17. Agricultural importance of algae | Abdel-Raouf | African Journal of ...

    African Journals Online (AJOL)

    Algae are a large and diverse group of microorganisms that can carry out photosynthesis since they capture energy from sunlight. Algae play an important role in agriculture where they are used as biofertilizer and soil stabilizers. Algae, particularly the seaweeds, are used as fertilizers, resulting in less nitrogen and ...

  18. The algae of Gaborone wastewater stabilization ponds: Implications ...

    African Journals Online (AJOL)

    The types of algae found in the wastewater stabilization ponds in Gaborone were studied. Being the base of the food chain in any aquatic habitat, algae contribute significantly to the functioning and value of the ponds. The (liversit)' and abundance of the algae in the two pond systems at Broadhurst and Phakalane were ...

  19. Research and development for algae-based technologies in Korea: a review of algae biofuel production.

    Science.gov (United States)

    Hong, Ji Won; Jo, Seung-Woo; Yoon, Ho-Sung

    2015-03-01

    This review covers recent research and development (R&D) activities in the field of algae-based biofuels in Korea. As South Korea's energy policy paradigm has focused on the development of green energies, the government has funded several algae biofuel R&D consortia and pilot projects. Three major programs have been launched since 2009, and significant efforts are now being made to ensure a sustainable supply of algae-based biofuels. If these R&D projects are executed as planned for the next 10 years, they will enable us to overcome many technical barriers in algae biofuel technologies and help Korea to become one of the leading countries in green energy by 2020.

  20. Photoprotection strategies of the alga Nannochloropsis gaditana

    NARCIS (Netherlands)

    Chukhutsina, Volha U.; Fristedt, Rikard; Morosinotto, Tomas; Croce, Roberta

    2017-01-01

    Nannochloropsis spp. are algae with high potential for biotechnological applications due to their capacity to accumulate lipids. However, little is known about their photosynthetic apparatus and acclimation/photoprotective strategies. In this work, we studied the mechanisms of non-photochemical

  1. Selenium accumulation and metabolism in algae.

    Science.gov (United States)

    Schiavon, Michela; Ertani, Andrea; Parrasia, Sofia; Vecchia, Francesca Dalla

    2017-08-01

    Selenium (Se) is an intriguing element because it is metabolically required by a variety of organisms, but it may induce toxicity at high doses. Algae primarily absorb selenium in the form of selenate or selenite using mechanisms similar to those reported in plants. However, while Se is needed by several species of microalgae, the essentiality of this element for plants has not been established yet. The study of Se uptake and accumulation strategies in micro- and macro-algae is of pivotal importance, as they represent potential vectors for Se movement in aquatic environments and Se at high levels may affect their growth causing a reduction in primary production. Some microalgae exhibit the capacity of efficiently converting Se to less harmful volatile compounds as a strategy to cope with Se toxicity. Therefore, they play a crucial role in Se-cycling through the ecosystem. On the other side, micro- or macro-algae enriched in Se may be used in Se biofortification programs aimed to improve Se content in human diet via supplementation of valuable food. Indeed, some organic forms of selenium (selenomethionine and methylselenocysteine) are known to act as anticarcinogenic compounds and exert a broad spectrum of beneficial effects in humans and other mammals. Here, we want to give an overview of the developments in the current understanding of Se uptake, accumulation and metabolism in algae, discussing potential ecotoxicological implications and nutritional aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Isolation of glycoproteins from brown algae.

    OpenAIRE

    Surendraraj, Alagarsamy; Farvin Koduvayur Habeebullah , Sabeena; Jacobsen, Charlotte

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme and Termamyl and the glycoproteins were isolated from these enzyme extracts.

  3. Fucoidans — sulfated polysaccharides of brown algae

    Science.gov (United States)

    Usov, Anatolii I.; Bilan, M. I.

    2009-08-01

    The methods of isolation of fucoidans and determination of their chemical structures are reviewed. The fucoidans represent sulfated polysaccharides of brown algae, the composition of which varies from simple fucan sulfates to complex heteropolysaccharides. The currently known structures of such biopolymers are presented. A variety of the biological activities of fucoidans is briefly summarised.

  4. The ice nucleation activity of extremophilic algae

    Czech Academy of Sciences Publication Activity Database

    Kvíderová, Jana; Hájek, J.; Worland, M. R.

    2013-01-01

    Roč. 34, č. 2 (2013), s. 137-148 ISSN 0143-2044 R&D Projects: GA AV ČR KJB601630808; GA AV ČR KJB600050708 Institutional support: RVO:67985939 Keywords : Ice nucleation * snow algae * lichen photobionts Subject RIV: EF - Botanics Impact factor: 0.640, year: 2013

  5. Washington State University Algae Biofuels Research

    Energy Technology Data Exchange (ETDEWEB)

    chen, Shulin [Washington State Univ., Pullman, WA (United States). Dept. of Biological Systems Engineering; McCormick, Margaret [Targeted Growth, Inc., Seattle, WA (United States); Sutterlin, Rusty [Inventure Renewables, Inc., Gig Harbor, WA (United States)

    2012-12-29

    The goal of this project was to advance algal technologies for the production of biofuels and biochemicals by establishing the Washington State Algae Alliance, a collaboration partnership among two private companies (Targeted Growth, Inc. (TGI), Inventure Chemicals (Inventure) Inc (now Inventure Renewables Inc) and Washington State University (WSU). This project included three major components. The first one was strain development at TGI by genetically engineering cyanobacteria to yield high levels of lipid and other specialty chemicals. The second component was developing an algal culture system at WSU to produce algal biomass as biofuel feedstock year-round in the northern states of the United States. This system included two cultivation modes, the first one was a phototrophic process and the second a heterotrophic process. The phototrophic process would be used for algae production in open ponds during warm seasons; the heterotrophic process would be used in cold seasons so that year-round production of algal lipid would be possible. In warm seasons the heterotrophic process would also produce algal seeds to be used in the phototrophic culture process. Selected strains of green algae and cyanobacteria developed by TGI were tested in the system. The third component was downstream algal biomass processing by Inventure that included efficiently harvesting the usable fuel fractions from the algae mass and effectively isolating and separating the usable components into specific fractions, and converting isolated fractions into green chemicals.

  6. Isolation of glycoproteins from brown algae

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme...

  7. Bromophenols in Marine Algae and Their Bioactivities

    DEFF Research Database (Denmark)

    Ming, Liu; Hansen, Poul Erik; Lin, Xiukun

    2011-01-01

    Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antioxidant, antimicrobial, anticancer, anti-diabetic, and anti-thrombotic effects. Here, we briefly review the recent progress of these marine algal biomaterials, with respect...

  8. Taxonomic Challenges and Distribution of Gracilarioid Algae ...

    African Journals Online (AJOL)

    This paper reviews the taxonomical literature of the gracilarioid algae from Tanzania, and provides information about their ecology and distribution based on an intensive regime of local collection. Its aim was to provide names, even if on a preliminary basis, for local gracilarioid taxa. Our revision shows that species ...

  9. Research for Developing Renewable Biofuels from Algae

    Energy Technology Data Exchange (ETDEWEB)

    Black, Paul N. [Univ. of Nebraska, Lincoln, NE (United States)

    2012-12-15

    Task A. Expansion of knowledge related to lipid production and secretion in algae A.1 Lipid biosynthesis in target algal species; Systems biology approaches are being used in combination with recent advances in Chlorella and Chlamydomonas genomics to address lipid accumulation in response to defined nutrient regimes. The UNL Algal Group continues screening additional species of Chlorella and other naturally occurring algae for those with optimal triglyceride production; Of the strains examined by the DOE's Aquatic Species Program, green algae, several species of Chlorella represent the largest group from which oleaginous candidates have been identified; A.1.1. Lipid profiling; Neutral lipid accumulation is routinely monitored by Nile red and BODIPY staining using high throughput strategies to screen for naturally occurring algae that accumulate triglyceride. These strategies complement those using spectrofluorometry to quantify lipid accumulation; Neutral lipid accumulation is routinely monitored by high performance thin-layer chromatography (HPTLC) and high performance liquid chromatography (HPLC) of lipid extracts in conjunction with; Carbon portioning experiments have been completed and the data currently are being analyzed and prepared for publication; Methods in the Black lab were developed to identify and quantify triacylglycerol (TAG), major membrane lipids [diacylglycerol trimethylhomoserine, phosphatidylethanolamine and chloroplast glycolipids], biosynthetic intermediates such as diacylglycerol, phosphatidic acid and lysophospholipids and different species of acyl-coenzyme A (acyl CoA).

  10. Usos industriales de las algas diatomeas.

    OpenAIRE

    Illana Esteban, Carlos

    2007-01-01

    Las diatomeas son algas microscópicas que habitan tanto en aguas dulces como marinas. Aparte de su destacado papel en la cadena trófica de los ecosistemas acuáticos, con el tiempo forman depósitos a los que el hombre ha encontrado abundantes aplicaciones prácticas.

  11. The Biology of blue-green algae

    National Research Council Canada - National Science Library

    Carr, Nicholas G; Whitton, B. A

    1973-01-01

    .... This book, extensively illustrated and thoroughly referenced, will provide the source material for students, and experienced as well as new research workers should find it of great value. A series of short appendices summarize details of culture collections, media and some specialized aspects of growing blue-green algae.

  12. Spirulina: The Alga That Can End Malnutrition.

    Science.gov (United States)

    Fox, Ripley D.

    1985-01-01

    One approach to eliminating malnutrition worldwide is to grow spirulina in recycled village wastes. Spirulina is a blue-green alga and a natural concentrated food. Spirulina can give poor villages a nutritional food supplement they can grow themselves and can reduce infectious disease at the same time. (Author/RM)

  13. Sterol chemotaxonomy of marine pelagophyte algae.

    Science.gov (United States)

    Giner, José-Luis; Zhao, Hui; Boyer, Gregory L; Satchwell, Michael F; Andersen, Robert A

    2009-07-01

    Several marine algae of the class Pelagophyceae produce the unusual marine sterol 24-propylidenecholesterol, mainly as the (24E)-isomer. The (24Z)-isomer had previously been considered as a specific biomarker for Aureococcus anophagefferens, the 'brown tide' alga of the Northeast coast of the USA. To test this hypothesis and to generate chemotaxonomic information, the sterol compositions of 42 strains of pelagophyte algae including 17 strains of Aureococcus anophagefferens were determined by GC analysis. A more comprehensive sterol analysis by HPLC and (1)H-NMR was obtained for 17 selected pelagophyte strains. All strains analyzed contained 24-propylidenecholesterol. In all strains belonging to the order Sarcinochrysidales, this sterol was found only as the (E)-isomer, while all strains in the order Pelagomonadales contained the (Z)-isomer, either alone or together with the (E)-isomer. The occurrence of Delta(22) and 24alpha-sterols was limited to the Sarcinochrysidales. The first occurrence of Delta(22)-24-propylcholesterol in an alga, CCMP 1410, was reported. Traces of the rare sterol 26,26-dimethyl-24-methylenecholesterol were detected in Aureococcus anophagefferens, and the (25R)-configuration was proposed, based on biosynthetic considerations. Traces of a novel sterol, 24-propylidenecholesta-5,25-dien-3beta-ol, were detected in several species.

  14. Sulfated polysaccharides as bioactive agents from marine algae.

    Science.gov (United States)

    Ngo, Dai-Hung; Kim, Se-Kwon

    2013-11-01

    Recently, much attention has been paid by consumers toward natural bioactive compounds as functional ingredients in nutraceuticals. Marine algae are considered as valuable sources of structurally diverse bioactive compounds. Marine algae are rich in sulfated polysaccharides (SPs) such as carrageenans in red algae, fucoidans in brown algae and ulvans in green algae. These SPs exhibit many health beneficial nutraceutical effects such as antioxidant, anti-allergic, anti-human immunodeficiency virus, anticancer and anticoagulant activities. Therefore, marine algae derived SPs have great potential to be further developed as medicinal food products or nutraceuticals in the food industry. This contribution presents an overview of nutraceutical effects and potential health benefits of SPs derived from marine algae. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Effects of phosphorus loading on interactions of algae and bacteria: reinvestigation of the 'phytoplankton–bacteria paradox' in a continuous cultivation system

    Czech Academy of Sciences Publication Activity Database

    Mindl, B.; Sonntag, B.; Pernthaler, J.; Vrba, Jaroslav; Psenner, R.; Posch, T.

    2005-01-01

    Roč. 38, č. 3 (2005), s. 203-213 ISSN 0948-3055. [ASLO Summer Meeting. Santiago de Compostela, 19.06.2005-24.06.2005] Grant - others:Austrian Science Fund(AT) FWF P14637- BIO ; MŠMT(CZ) Kontakt 2003-6 Institutional research plan: CEZ:AV0Z6017912 Keywords : algae–bacteria interaction * Cryptomonas phaseolus * phosphorus Subject RIV: EH - Ecology, Behaviour Impact factor: 2.531, year: 2005

  16. Ku-mediated coupling of DNA cleavage and repair during programmed genome rearrangements in the ciliate Paramecium tetraurelia.

    Directory of Open Access Journals (Sweden)

    Antoine Marmignon

    2014-08-01

    Full Text Available During somatic differentiation, physiological DNA double-strand breaks (DSB can drive programmed genome rearrangements (PGR, during which DSB repair pathways are mobilized to safeguard genome integrity. Because of their unique nuclear dimorphism, ciliates are powerful unicellular eukaryotic models to study the mechanisms involved in PGR. At each sexual cycle, the germline nucleus is transmitted to the progeny, but the somatic nucleus, essential for gene expression, is destroyed and a new somatic nucleus differentiates from a copy of the germline nucleus. In Paramecium tetraurelia, the development of the somatic nucleus involves massive PGR, including the precise elimination of at least 45,000 germline sequences (Internal Eliminated Sequences, IES. IES excision proceeds through a cut-and-close mechanism: a domesticated transposase, PiggyMac, is essential for DNA cleavage, and DSB repair at excision sites involves the Ligase IV, a specific component of the non-homologous end-joining (NHEJ pathway. At the genome-wide level, a huge number of programmed DSBs must be repaired during this process to allow the assembly of functional somatic chromosomes. To understand how DNA cleavage and DSB repair are coordinated during PGR, we have focused on Ku, the earliest actor of NHEJ-mediated repair. Two Ku70 and three Ku80 paralogs are encoded in the genome of P. tetraurelia: Ku70a and Ku80c are produced during sexual processes and localize specifically in the developing new somatic nucleus. Using RNA interference, we show that the development-specific Ku70/Ku80c heterodimer is essential for the recovery of a functional somatic nucleus. Strikingly, at the molecular level, PiggyMac-dependent DNA cleavage is abolished at IES boundaries in cells depleted for Ku80c, resulting in IES retention in the somatic genome. PiggyMac and Ku70a/Ku80c co-purify as a complex when overproduced in a heterologous system. We conclude that Ku has been integrated in the Paramecium

  17. Biofuels from algae for sustainable development

    International Nuclear Information System (INIS)

    Demirbas, M. Fatih

    2011-01-01

    Microalgae are photosynthetic microorganisms that can produce lipids, proteins and carbohydrates in large amounts over short periods of time. These products can be processed into both biofuels and useful chemicals. Two algae samples (Cladophora fracta and Chlorella protothecoid) were studied for biofuel production. Microalgae appear to be the only source of renewable biodiesel that is capable of meeting the global demand for transport fuels. Microalgae can be converted to biodiesel, bioethanol, bio-oil, biohydrogen and biomethane via thermochemical and biochemical methods. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae can be grown almost anywhere, even on sewage or salt water, and does not require fertile land or food crops, and processing requires less energy than the algae provides. Microalgae have much faster growth-rates than terrestrial crops. the per unit area yield of oil from algae is estimated to be from 20,000 to 80,000 liters per acre, per year; this is 7-31 times greater than the next best crop, palm oil. Algal oil can be used to make biodiesel for cars, trucks, and airplanes. The lipid and fatty acid contents of microalgae vary in accordance with culture conditions. The effect of temperature on the yield of hydrogen from two algae (C. fracta and C. protothecoid) by pyrolysis and steam gasification were investigated in this study. In each run, the main components of the gas phase were CO 2 , CO, H 2 , and CH 4 .The yields of hydrogen by pyrolysis and steam gasification processes of the samples increased with temperature. The yields of gaseous products from the samples of C. fracta and C. protothecoides increased from 8.2% to 39.2% and 9.5% to 40.6% by volume, respectively, while the final pyrolysis temperature was increased from 575 to 925 K. The percent of hydrogen in gaseous products from the samples of C. fracta and C. protothecoides increased from 25.8% to 44.4% and 27.6% to 48.7% by volume

  18. Bioconcentration of tetrachlorobenzene in marine algae

    Science.gov (United States)

    Wang, Xiu-Lin; Ma, Yan-Jun; Cheng, Gang; Yu, Wei-Jun; Zhang, Li-Jun

    1997-09-01

    Bioconcentration of tetrachlorobenzene (TeCB) in Chlorella marine, Nannochloropsis oculata, Pyramidomonas sp., Platymonas subcordiformis, and Phaeodactylum tricornutum; and toxicity of TeCB to the marine algae were tested. Values of bioconcentration potential parameters, including uptake rate constant k 1, elimination rate constant k 2 and bioconcentration factor BCF, were obtained not only from the time course of TeCB uptake by the marine algae by using a bioconcentration model, but also from the acute toxicity test data for percent inhibition PI(%)˜exposure concentration of TeCB-time by using a combined bioconcentration and probability model. The results showed good relationship between k 1(TOXIC) and k 1(UPTAKE) and k 2(TOXIC), k 2(UPTAKE), and BCF D(IOXIC) and BCF D(UPTAKE). Especially, the values of BCF D(TOXIC) were well consistent with those of BCF D(UPTAKE).

  19. [Chemical constituents from red alga Corallina pilulifera].

    Science.gov (United States)

    Yuan, Zhao-Hui; Han, Li-Jun; Fan, Xiao; Li, Shuai; Shi, Da-Yong; Sun, Jie; Ma, Ming; Yang, Yong-Chun; Shi, Jian-Gong

    2006-11-01

    To investigate the chemical constituents of red alga Corallina pilulifera. Compounds were isolated by normal phase silica gel and Sephadex LH - 20 gel column chromatography, reverse phase HPLC and recrystallization. Their structures were elucidated by spectroscopic methods including MS, 1H-NMR, 13C-NMR, HSQC, HMBC. Cytotoxicity of the compounds was screened by using standard MTT method. Seven compounds were isolated from red alga C. pilulifera, their structures were identified as (E) -phytol epoxide (1), phytenal (2), phytol (3), dehydrovomifoliol (4), loliolide (5), 3beta-hydroxy-5alpha, 6alpha-epoxy-7-megastigmene-9-one (6), 4-hydroxybenzaldehyde (7). All of the compounds were obtained from this species for the first time. These compounds were inactive (IC50 > 10 microg x mL(-1)) in the MTT assay.

  20. Radiokinetic study in betony marine algae

    International Nuclear Information System (INIS)

    Azevedo Gouvea, V. de.

    1981-01-01

    The influx and outflux kinetics of some radionuclides in algae of the Rio de Janeiro coastline, were studied in order to select bioindicators for radioactive contamination in aquatic media, due to the presence of Nuclear Power Stations. Bioassays of the concentration and loss of radionuclides such as 137 Cs, 51 Cr, 60 Co and 131 I were performed in 1000cm 3 aquarium under controlled laboratory conditions, using a single channel gamma counting system, to study the species of algae most frequently found in the region. The concentration and loss parameters for all the species and radionuclides studied were obtained from the normalized results. The loss parameters were computerwise adjusted using Powell's multiparametric method. (author)

  1. Hyperaccumulation of radioactive isotopes by marine algae

    International Nuclear Information System (INIS)

    Ishii, Toshiaki; Hirano, Shigeki; Watabe, Teruhisa

    2003-01-01

    Hyperaccumlators are effective indicator organisms for monitoring marine pollution by heavy metals and artificial radionuclides. We found a green algae, Bryopsis maxima that hyperaccumulate a stable and radioactive isotopes such as Sr-90, Tc-99, Ba-138, Re-187, and Ra-226. B. maxima showed high concentration factors for heavy alkali earth metals like Ba and Ra, compared with other marine algae in Japan. Furthermore, this species had the highest concentrations for Tc-99 and Re-187. The accumulation and excretion patterns of Sr-85 and Tc-95m were examined by tracer experiments. The chemical states of Sr and Re in living B. maxima were analyzed by HPLC-ICP/MS, LC/MS, and X-ray absorption fine structure analysis using synchrotron radiation. (author)

  2. Multiplicity of viral infection in brown algae

    OpenAIRE

    Stevens, Kim

    2014-01-01

    Brown algae are important primary producers and habitat formers in coastal environments and are believed to have evolved multicellularity independently of the other eukaryotes. The phaeoviruses that infect them form a stable lysogenic relationship with their host via genome integration, but have only been extensively studied in two genera: Ectocarpus and Feldmannia. In this study I aim to improve our understanding of the genetic diversity, host range and distribution of phaeoviruses. Seq...

  3. Algae-Derived Dietary Ingredients Nourish Animals

    Science.gov (United States)

    2015-01-01

    In the 1980s, Columbia, Maryland-based Martek Biosciences Corporation worked with Ames Research Center to pioneer the use of microalgae as a source of essential omega-3 fatty acids, work that led the company to develop its highly successful Formulaid product. Now the Nutritional Products Division of Royal DSM, the company also manufactures DHAgold, a nutritional supplement for pets, livestock and farm-raised fish that uses algae to deliver docosahexaenoic acid (DHA).

  4. Electro-coagulation-flotation process for algae removal

    International Nuclear Information System (INIS)

    Gao Shanshan; Yang Jixian; Tian Jiayu; Ma Fang; Tu Gang; Du Maoan

    2010-01-01

    Algae in surface water have been a long-term issue all over the world, due to their adverse influence on drinking water treatment process as well as drinking water quality. The algae removal by electro-coagulation-flotation (ECF) technology was investigated in this paper. The results indicated that aluminum was an excellent electrode material for algae removal as compared with iron. The optimal parameters determined were: current density = 1 mA/cm 2 , pH = 4-7, water temperature = 18-36 deg. C, algae density = 0.55 x 10 9 -1.55 x 10 9 cells/L. Under the optimal conditions, 100% of algae removal was achieved with the energy consumption as low as 0.4 kWh/m 3 . The ECF performed well in acid and neutral conditions. At low initial pH of 4-7, the cell density of algae was effectively removed in the ECF, mainly through the charge neutralization mechanism; while the algae removal worsened when the pH increased (7-10), and the main mechanism shifted to sweeping flocculation and enmeshment. The mechanisms for algae removal at different pH were also confirmed by atomic force microscopy (AFM) analysis. Furthermore, initial cell density and water temperature could also influence the algae removal. Overall, the results indicated that the ECF technology was effective for algae removal, from both the technical and economical points of view.

  5. Regulating cellular trace metal economy in algae.

    Science.gov (United States)

    Blaby-Haas, Crysten E; Merchant, Sabeeha S

    2017-10-01

    As indispensable protein cofactors, Fe, Mn, Cu and Zn are at the center of multifaceted acclimation mechanisms that have evolved to ensure extracellular supply meets intracellular demand. Starting with selective transport at the plasma membrane and ending in protein metalation, metal homeostasis in algae involves regulated trafficking of metal ions across membranes, intracellular compartmentalization by proteins and organelles, and metal-sparing/recycling mechanisms to optimize metal-use efficiency. Overlaid on these processes are additional circuits that respond to the metabolic state as well as to the prior metal status of the cell. In this review, we focus on recent progress made toward understanding the pathways by which the single-celled, green alga Chlamydomonas reinhardtii controls its cellular trace metal economy. We also compare these mechanisms to characterized and putative processes in other algal lineages. Photosynthetic microbes continue to provide insight into cellular regulation and handling of Cu, Fe, Zn and Mn as a function of the nutritional supply and cellular demand for metal cofactors. New experimental tools such as RNA-Seq and subcellular metal imaging are bringing us closer to a molecular understanding of acclimation to supply dynamics in algae and beyond. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. New records of marine algae in Vietnam

    Science.gov (United States)

    Le Hau, Nhu; Ly, Bui Minh; Van Huynh, Tran; Trung, Vo Thanh

    2015-06-01

    In May, 2013, a scientific expedition was organized by the Vietnam Academy of Science and Technology (VAST) and the Far Eastern Branch of the Russian Academy of Sciences (FEBRAS) through the frame of the VAST-FEBRAS International Collaboration Program. The expedition went along the coast of Vietnam from Quang Ninh to Kien Giang. The objective was to collect natural resources to investigate the biological and biochemical diversity of the territorial waters of Vietnam. Among the collected algae, six taxa are new records for the Vietnam algal flora. They are the red algae Titanophora pikeana (Dickie) Feldmann from Cu Lao Xanh Island, Laurencia natalensis Kylin from Tho Chu Island, Coelothrix irregularis (Harvey) Børgesen from Con Dao Island, the green algae Caulerpa oligophylla Montagne, Caulerpa andamanensis (W.R. Taylor) Draisma, Prudhomme et Sauvage from Phu Quy Island, and Caulerpa falcifolia Harvey & Bailey from Ly Son Island. The seaweed flora of Vietnam now counts 833 marine algal taxa, including 415 Rhodophyta, 147 Phaeophyceae, 183 Chlorophyta, and 88 Cyanobacteria.

  7. Functional properties of carotenoids originating from algae.

    Science.gov (United States)

    Christaki, Efterpi; Bonos, Eleftherios; Giannenas, Ilias; Florou-Paneri, Panagiota

    2013-01-15

    Carotenoids are isoprenoid molecules which are synthesised de novo by photosynthetic plants, fungi and algae and are responsible for the orange, yellow and some red colours of various fruits and vegetables. Carotenoids are lipophilic compounds, some of which act as provitamins A. These compounds can be divided into xanthophylls and carotenes. Many macroalgae and microalgae are rich in carotenoids, where these compounds aid in the absorption of sunlight. Industrially, these carotenoids are used as food pigments (in dairy products, beverages, etc.), as feed additives, in cosmetics and in pharmaceuticals, especially nowadays when there is an increasing demand by consumers for natural products. Production of carotenoids from algae has many advantages compared to other sources; for example, their production is cheap, easy and environmentally friendly; their extraction is easier, with higher yields, and there is no lack of raw materials or limited seasonal variation. Recently, there has been considerable interest in dietary carotenoids with respect to their antioxidant properties and their ability to reduce the incidence of some chronic diseases where free radicals are involved. Possibly, carotenoids protect cells from oxidative stress by quenching singlet oxygen damage with various mechanisms. Therefore, carotenoids derived from algae could be a leading natural resource in the research for potential functional ingredients. Copyright © 2012 Society of Chemical Industry.

  8. Structural studies demonstrating a bacteriophage-like replication cycle of the eukaryote-infecting Paramecium bursaria chlorella virus-1

    Science.gov (United States)

    Shimoni, Eyal; Dadosh, Tali; Rechav, Katya; Unger, Tamar

    2017-01-01

    A fundamental stage in viral infection is the internalization of viral genomes in host cells. Although extensively studied, the mechanisms and factors responsible for the genome internalization process remain poorly understood. Here we report our observations, derived from diverse imaging methods on genome internalization of the large dsDNA Paramecium bursaria chlorella virus-1 (PBCV-1). Our studies reveal that early infection stages of this eukaryotic-infecting virus occurs by a bacteriophage-like pathway, whereby PBCV-1 generates a hole in the host cell wall and ejects its dsDNA genome in a linear, base-pair-by-base-pair process, through a membrane tunnel generated by the fusion of the virus internal membrane with the host membrane. Furthermore, our results imply that PBCV-1 DNA condensation that occurs shortly after infection probably plays a role in genome internalization, as hypothesized for the infection of some bacteriophages. The subsequent perforation of the host photosynthetic membranes presumably enables trafficking of viral genomes towards host nuclei. Previous studies established that at late infection stages PBCV-1 generates cytoplasmic organelles, termed viral factories, where viral assembly takes place, a feature characteristic of many large dsDNA viruses that infect eukaryotic organisms. PBCV-1 thus appears to combine a bacteriophage-like mechanism during early infection stages with a eukaryotic-like infection pathway in its late replication cycle. PMID:28850602

  9. Stage-specific appearance of cytoplasmic microtubules around the surviving nuclei during the third prezygotic division of Paramecium.

    Science.gov (United States)

    Wang, Yi-Wen; Yuan, Jin-Qiang; Gao, Xin; Yang, Xian-Yu

    2012-12-01

    There are six micronuclear divisions during conjugation of Paramecium caudatum: three prezygotic and three postzygotic divisions. Four haploid nuclei are formed during the first two meiotic prezygotic divisions. Usually only one meiotic product is located in the paroral cone (PC) region at the completion of meiosis, which survives and divides mitotically to complete the third prezygotic division to yield a stationary and a migratory pronucleus. The remaining three located outside of the PC degenerate. The migratory pronuclei are then exchanged between two conjugants and fuse with the stationary pronuclei to form synkarya, which undergo three successive divisions (postzygotic divisions). However, little is known about the surviving mechanism of the PC nuclei. In the current study, stage-specific appearance of cytoplasmic microtubules (cMTs) was indicated during the third prezygotic division by immunofluorescence labeling with anti-alpha tubulin antibodies surrounding the surviving nuclei, including the PC nuclei and the two types of prospective pronuclei. This suggested that cMTs were involved in the formation of a physical barrier, whose function may relate to sequestering and protecting the surviving nuclei from the major cytoplasm, where degeneration of extra-meiotic products occurs, another important nuclear event during the third prezygotic division.

  10. Variation in ribosomal and mitochondrial DNA sequences demonstrates the existence of intraspecific groups in Paramecium multimicronucleatum (Ciliophora, Oligohymenophorea).

    Science.gov (United States)

    Tarcz, Sebastian; Potekhin, Alexey; Rautian, Maria; Przyboś, Ewa

    2012-05-01

    This is the first phylogenetic study of the intraspecific variability within Paramecium multimicronucleatum with the application of two-loci analysis (ITS1-5.8S-ITS2-5'LSU rDNA and COI mtDNA) carried out on numerous strains originated from different continents. The species has been shown to have a complex structure of several sibling species within taxonomic species. Our analysis revealed the existence of 10 haplotypes for the rDNA fragment and 15 haplotypes for the COI fragment in the studied material. The mean distance for all of the studied P. multimicronucleatum sequence pairs was p=0.025/0.082 (rDNA/COI). Despite the greater variation of the COI fragment, the COI-derived tree topology is similar to the tree topology constructed on the basis of the rDNA fragment. P. multimicronucleatum strains are divided into three main clades. The tree based on COI fragment analysis presents a greater resolution of the studied P. multimicronucleatum strains. Our results indicate that the strains of P. multimicronucleatum that appear in different clades on the trees could belong to different syngens. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Putative DNA-dependent RNA polymerase in Mitochondrial Plasmid of Paramecium caudatum Stock GT704

    Directory of Open Access Journals (Sweden)

    Trina Ekawati Tallei

    2015-10-01

    Full Text Available Mitochondria of Paramecium caudatum stock GT704 has a set of four kinds of linear plasmids with sizes of 8.2, 4.1, 2.8 and 1.4 kb. The plasmids of 8.2 and 2.8 kb exist as dimers consisting of 4.1- and 1.4-kb monomers, respectively. The plasmid 2.8 kb, designated as pGT704-2.8, contains an open reading frame encodes for putative DNA-dependent RNA polymerase (RNAP. This study reveals that this RNAP belongs to superfamily of DNA/RNA polymerase and family of T7/T3 single chain RNA polymerase and those of mitochondrial plasmid of fungi belonging to Basidiomycota and Ascomycota. It is suggested that RNAP of pGT704-2.8 can perform transcription without transcription factor as promoter recognition. Given that only two motifs were found, it could not be ascertained whether this RNAP has a full function independently or integrated with mtDNA in carrying out its function.

  12. Structural studies demonstrating a bacteriophage-like replication cycle of the eukaryote-infecting Paramecium bursaria chlorella virus-1.

    Directory of Open Access Journals (Sweden)

    Elad Milrot

    2017-08-01

    Full Text Available A fundamental stage in viral infection is the internalization of viral genomes in host cells. Although extensively studied, the mechanisms and factors responsible for the genome internalization process remain poorly understood. Here we report our observations, derived from diverse imaging methods on genome internalization of the large dsDNA Paramecium bursaria chlorella virus-1 (PBCV-1. Our studies reveal that early infection stages of this eukaryotic-infecting virus occurs by a bacteriophage-like pathway, whereby PBCV-1 generates a hole in the host cell wall and ejects its dsDNA genome in a linear, base-pair-by-base-pair process, through a membrane tunnel generated by the fusion of the virus internal membrane with the host membrane. Furthermore, our results imply that PBCV-1 DNA condensation that occurs shortly after infection probably plays a role in genome internalization, as hypothesized for the infection of some bacteriophages. The subsequent perforation of the host photosynthetic membranes presumably enables trafficking of viral genomes towards host nuclei. Previous studies established that at late infection stages PBCV-1 generates cytoplasmic organelles, termed viral factories, where viral assembly takes place, a feature characteristic of many large dsDNA viruses that infect eukaryotic organisms. PBCV-1 thus appears to combine a bacteriophage-like mechanism during early infection stages with a eukaryotic-like infection pathway in its late replication cycle.

  13. The first European stand of Paramecium sonneborni (P. aurelia complex), a species known only from North America (Texas, USA).

    Science.gov (United States)

    Przyboś, Ewa; Tarcz, Sebastian; Rautian, Maria; Lebedeva, Natalia

    2014-06-01

    P. aurelia is currently defined as a complex of 15 sibling species including 14 species designated by Sonneborn (1975) and one, P. sonneborni, by Aufderheide et al. (1983). The latter was known from only one stand (Texas, USA). The main reason for the present study was a new stand of Paramecium in Cyprus, with strains recognized as P. sonneborni based on the results of strain crosses, cytological slides, and molecular analyses of three loci (ITS1-5.8S-ITS2-5'LSU rDNA, COI, CytB). The new stand of P. sonneborni in Europe shows that the species, previously considered endemic, may have a wider range. This demonstrates the impact of under-sampling on the knowledge of the biogeography of microbial eukaryotes. Phylogenetic trees based on all the studied fragments revealed that P. sonneborni forms a separate cluster that is closer to P. jenningsi and P. schewiakoffi than to the other members of the P. aurelia complex. Copyright © 2014 Elsevier GmbH. All rights reserved.

  14. Basal body duplication in Paramecium: the key role of Bld10 in assembly and stability of the cartwheel.

    Science.gov (United States)

    Jerka-Dziadosz, Maria; Gogendeau, Delphine; Klotz, Catherine; Cohen, Jean; Beisson, Janine; Koll, France

    2010-03-01

    Basal bodies which nucleate cilia and flagella, and centrioles which organize centrosomes share the same architecture characterized by the ninefold symmetry of their microtubular shaft. Among the conserved proteins involved in the biogenesis of the canonical 9-triplet centriolar structures, Sas-6 and Bld10 proteins have been shown to play central roles in the early steps of assembly and in establishment/stabilization of the ninefold symmetry. Using fluorescent tagged proteins and RNAi to study the localization and function of these two proteins in Paramecium, we focused on the early effects of their depletion, the consequences of their overexpression and their functional interdependence. We find that both genes are essential and their depletion affects cartwheel assembly and hence basal body duplication. We also show that, contrary to Sas6p, Bld10p is not directly responsible for the establishment of the ninefold symmetry, but is required not only for new basal body assembly and stability but also for Sas6p maintenance at mature basal bodies. Finally, ultrastructural analysis of cells overexpressing either protein revealed two types of early assembly intermediates, hub-like structures and generative discs, suggesting a conserved scaffolding process. (c) 2010 Wiley-Liss, Inc.

  15. Complement consumption by double culture of Paramecium caudatum and Aerobacter cloacae in repeated examination in relation to the individual radiosensitivity

    International Nuclear Information System (INIS)

    Bernasovsky, I.; Cabadaj, S.; Praslicka, M.; Chlebovska, K.

    1976-01-01

    Two sets of rats were repeatedly examined by the complement consumption test with a double culture of Paramecium caudatum and Aerobacter cloacae (DPA). The first set was examined 11 days and 1 day before irradiation with 0.15 C/kg, the second 6 days before and 4 days after irradiation with 0.15 C/kg. The intensity of reaction and thus the relative titres of the examined antibodies were expressed numerically by the NMHD symbol, i.e., by the number of minimal hemolytical complement doses consumed in the reaction. This reaction is known as the NMHD test. The proportion of rats with a high NMHD which survived 30 days after irradiation was higher than that of rats with low reaction values. Rats having in one examination a high NMHD value and in the second a low one (the sequence high-low or low-high is not important) were more radioresistant than those with permanently low reaction values and did not basically differ from the animals with permanently high NMHD values. Bacteriae Aerobacter cloacae represent the antigenically effective substance of DNA. (author)

  16. Paramecium tetraurelia growth stimulation under low-level chronic irradiation: investigations on a possible mechanism. [/sup 60/Co

    Energy Technology Data Exchange (ETDEWEB)

    Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H.

    1982-12-01

    Experiments were carried out to demonstrate the effects of low-level chronic irradiation on Paramecium tetraurelia proliferation. Biological effects were strongly dependent on the bacterial density of culture medium and more exactly on the catalase content of the medium. Significant growth stimulation was found under /sup 60/Co chronic irradiation at a dose rate of 2 rad/year when paramecia were grown in a medium containing a high bacterial concentration (2.5 x 10/sup 2/ cells/m) or supplemented with catalase (300 U/ml). In a medium with a low bacterial density (1 x 10/sup 6/ cell/ml) or supplemented with a catalase activity inhibitor, growth simulation was preceded by a transitory inhibiting effect which could be correlated with extracellularly radioproduced H/sub 2/O/sub 2/. H/sub 2/O/sub 2/ addition appeared to be able to simulate the biological effects of chronic irradiation. A possible mechanism is discussed.We proposed that the stimulating effects were the result of intracellular enzymatic scavenging of radioproduced H/sub 2/O/sub 2/.

  17. The effect of X-rays on strains and syngens of Paramecium aurelia differing in genetic affinity

    International Nuclear Information System (INIS)

    Komala, Z.

    1975-01-01

    Experiments were carried out on syngens 1, 3, 5, and 9 of Paramecium aurelia. A sublethal dose of X-rays was used (about 31 kR). The conjugants were irradiated in the prophase stage of meiotic division. The percentage of surviving clones and the rate of vegetative reproduction were studied. Karyometric investigations of some strains were also performed. The obtained results indicate that the fate and behavior of the progeny (F 1 and F 2 ) of irradiated conjugants in various syngens of P aurelia are a reflection of the genetic affinity connecting these syngens. Syngens 1, 3, and 5, which are more closely related, although in different degrees, included the group of more radiation-sensitive strains. As opposed to this, the strains of syngen 9 of P. aurelia, which is genetically distant from the former group, were characterized by considerable radiation-resistance. Karyometric investigations revealed that strains also showed considerable differences in the mutual relations of mean volumes of macro- and micro-nuclei. (author)

  18. Effect of local UV irradiation of generative nuclei of Paramecium caudatum on sexual functions of the cells

    International Nuclear Information System (INIS)

    Skoblo, I.I.; Borkhsenius, O.N.

    1979-01-01

    The functions of micronucleus (MI) were studied in the period of the sexual process in Paramecium caudatum-infusoria the descendants of the cells, whose micronucleus was locally irradiated with UV rays at the dose of 3060 erg/mm 2 . It has been found that the descendants of the irradiated cells (the cells of UV clones) can be involved into the sexual process irrespoctive of the morphological type of their MI. Four out of forteen UV clones have changed the initial mating type for the opposite one. It is suggested that the change of the mating type is related to the changes of MI genome resulted from UV irradiation. The pathway of nuclear transformations in the course of sexual process was traced in cells of three UV clones. It has been found, that local UV irradiation of MI causes a number of deviations in the behaviour of MI derivatives in the metagamic part of the sexual process in the clones, whose MI have undergone substantial morphological changes. The exconjugants produced by crossing of UV clones with such changed MI and the normal test-clone were characterized by low viability

  19. Influence of local UV-micro-irradiation on nuclear apparatus and cytoplasm of a ciliate Paramecium caudatum

    International Nuclear Information System (INIS)

    Fokin, S.I.; Osipov, D.V.

    1975-01-01

    The paper describes the first attempt to use ultra-violet microirradiation (u.v. injection) in the study of nuclear dualism of infusoria. The u.v. injection affords a means of selectively inactivating individual components of the nuclear apparatus of living infusoria and observing the consequences of an operation in the remote progeny of an irradiated cell. The procedures for applying the u.v. injection have been developed for the infusoria Paramecium caudatum. A rotating compressor of novel design was used to immobilize the infusoria at the time of operation. The effective u.v. doses were chosen and comparative sensitivities of the cytoplasm, the macronucleus, the micronucleus and the symbiotic bacteria of the micronucleus - omega particles - were determined. Healthy infected cells were irradiated in different variants. Depending on dose, the u.v. injection can result in a reduction in the cloning efficiency, the loss of omega particles from the micronucleus and the appearance of cells with 2-3 micronuclei and, possibly, amicronuclear cells. Visible light repairs the damage caused by the u.v. injection. (photoreactivation). (author)

  20. Purification, in vitro reassembly, and preliminary sequence analysis of epiplasmins, the major constituent of the membrane skeleton of Paramecium.

    Science.gov (United States)

    Coffe, G; Le Caer, J P; Lima, O; Adoutte, A

    1996-01-01

    The epiplasmic layer, a continuous rigid granulo-fibrillar sheet directly subtending the surface membranes of Paramecium, is one of the outermost of the various cytoskeletal networks that compose it cortex. We have previously shown that the epiplasm consists of a set of 30 to 50 protein bands on SDS-PAGE in the range 50 to 33 kDa, the epiplasmins. We report a purification procedure for the set of epiplasmic proteins, a description of their physicochemical and reassembly properties, and a preliminary characterization of their sequence. The conditions for solubilization of the epiplasm and for in vitro reassembly of its purified constituents ar described. Reassembly of the entire set of proteins and of some (but not all) subsets are shown to yield filamentous aggregates. Microsequences of two purified bands of epiplasmins reveal a striking amino acid sequence consisting of heptad repeats of only three main amino acids, P, V, and Q. These repeats were confirmed by DNA sequencing of polymerase chain reaction products. The motif is QPVQ-h, in which h is a hydrophobic residue. This may constitute the core of the epiplasmin sequence and, in view of the tendency of such a sequence to form a coiled-coil, may account for the remarkable self-aggregation properties of epiplasmins.

  1. Short-pulse neodymium:yttrium-aluminium garnet (Nd:YAG 1064nm) laser irradiation photobiomodulates mitochondria activity and cellular multiplication of Paramecium primaurelia (Protozoa).

    Science.gov (United States)

    Amaroli, Andrea; Benedicenti, Alberico; Ravera, Silvia; Parker, Steven; Selting, Wayne; Panfoli, Isabella; Benedicenti, Stefano

    2017-10-01

    Few studies exist to explore the potential photobiomodulation (PBM) effect of neodymium:yttrium-aluminium garnet (Nd:YAG) laser irradiation using a flat-top handpiece delivery system. In this study, we explored the photobiomodulation effect of that laser, on Paramecium primaurelia. The parameters for the different study groups were: 0.50W, 10Hz, 100msp, 30J/cm 2 ; 0.75W, 10Hz, 100msp, 45J/cm 2 ; 1.00W, 10Hz, 100msp, 60J/cm 2 ; 1.25W, 10Hz, 100msp, 75J/cm 2 and 1.50W, 10Hz, 100msp, 90J/cm 2 . Our results suggest that only the parameter 0.5W, 10Hz, 100msp, 30J/cm 2 positively photobiomodulates the Paramecium cells inducing an increment in oxygen consumption, endogenous ATP synthesis and fission rate rhythm. Applying the laser energy with parameters of 1.25W, 10Hz, 100msp, 75J/cm 2 and 1.50W, 10Hz, 100msp, 90J/cm 2 , induce adverse effect on the Paramecium cells, which protect themselves through the increase in Heat Shock Protein-70 (HSP70). The data presented in our work support our assumption that, when using appropriate parameters of irradiation, the 1064nm Nd:YAG laser with flat-top handpiece could be a valuable aid for effective clinical application of PBM. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. Interspecific variation in total phenolic content in temperate brown algae

    Directory of Open Access Journals (Sweden)

    Anna Maria Mannino

    2017-09-01

    Full Text Available Marine algae synthesize secondary metabolites such as polyphenols that function as defense and protection mechanisms. Among brown algae, Fucales and Dictyotales (Phaeophyceae contain the highest levels of phenolic compounds, mainly phlorotannins, that play multiple roles. Four temperate brown algae (Cystoseira amentacea, Cystoseira compressa, Dictyopteris polypodioides and Padina pavonica were studied for total phenolic contents. Total phenolic content was determined colorimetrically with the Folin-Ciocalteu reagent. Significant differences in total phenolic content were observed between leathery and sheetlike algae and also within each morphological group. Among the four species, the sheet-like alga D. polypodioides, living in the upper infralittoral zone, showed the highest concentration of phenolic compounds. These results are in agreement with the hypothesis that total phenolic content in temperate brown algae is influenced by a combination of several factors, such as growth form, depth, and exposition to solar radiation.

  3. Algae to Economically Viable Low-Carbon-Footprint Oil.

    Science.gov (United States)

    Bhujade, Ramesh; Chidambaram, Mandan; Kumar, Avnish; Sapre, Ajit

    2017-06-07

    Algal oil as an alternative to fossil fuel has attracted attention since the 1940s, when it was discovered that many microalgae species can produce large amounts of lipids. Economics and energy security were the motivational factors for a spurt in algae research during the 1970s, 1990s, and early 2000s. Whenever crude prices declined, research on algae stopped. The scenario today is different. Even given low and volatile crude prices ($30-$50/barrel), interest in algae continues all over the world. Algae, with their cure-all characteristics, have the potential to provide sustainable solutions to problems in the energy-food-climate nexus. However, after years of effort, there are no signs of algae-to-biofuel technology being commercialized. This article critically reviews past work; summarizes the current status of the technology; and based on the lessons learned, provides a balanced perspective on a potential path toward commercialization of algae-to-oil technology.

  4. Mécanismes et fonctions de la voie d'ARN interférence induite par ARN double brin chez Paramecium tetraurelia

    OpenAIRE

    Carradec , Quentin

    2014-01-01

    The ciliate Paramecium tetraurelia is an interesting model to study the diversity and evolution of RNA interference (RNAi) pathways. One of the vegetative RNAi pathways is induced by feeding cells with bacteria producing double-stranded RNA (dsRNA) homologous to a given gene, which is then post-transcriptionally silenced through the production of 23-nt siRNAs. A forward genetic screen allowed us to obtain Mendelian mutants deficient in dsRNA-induced RNAi, and mutated genes were identified by ...

  5. Production and characterization of algae extract from Chlamydomonas reinhardtii

    Directory of Open Access Journals (Sweden)

    Weston Kightlinger

    2014-01-01

    Conclusions: This study showed that algae extract derived from C. reinhardtii is similar, if not superior, to commercially available yeast extract in nutrient content and effects on the growth and metabolism of E. coli and S. cerevisiae. Bacto™ yeast extract is valued at USD $0.15–0.35 per gram, if algae extract was sold at similar prices, it would serve as a high-value co-product in algae-based fuel processes.

  6. Antimicrobial Activity of Extracts from Six Green Algae from Tanzania

    OpenAIRE

    Mtolera, M.S.P.; Semesi, A.

    1996-01-01

    Many algae species have been shown to have bactericidal or bacteriostatic substances (Glombitza, I979;Michaneck, 1979; Caccamese et al., 1980; Fenical & Paul, 1984; Niang& Hung, 1984). The antibacterialagents found in the algae include amino acids, terpenoids, phlorotannins, acrylic acid, phenoliccompounds, steroids, halogenated ketones and alkanes, cyclic polysulphides and fatty acids. In a large numberof marine algae antimicrobial activities are attributed to the presence of acrylic acid.

  7. Method and apparatus for iterative lysis and extraction of algae

    Science.gov (United States)

    Chew, Geoffrey; Boggs, Tabitha; Dykes, Jr., H. Waite H.; Doherty, Stephen J.

    2015-12-01

    A method and system for processing algae involves the use of an ionic liquid-containing clarified cell lysate to lyse algae cells. The resulting crude cell lysate may be clarified and subsequently used to lyse algae cells. The process may be repeated a number of times before a clarified lysate is separated into lipid and aqueous phases for further processing and/or purification of desired products.

  8. Genome Annotation and Transcriptomics of Oil-Producing Algae

    Science.gov (United States)

    2015-03-16

    AFRL-OSR-VA-TR-2015-0103 GENOME ANNOTATION AND TRANSCRIPTOMICS OF OIL-PRODUCING ALGAE Sabeeha Merchant UNIVERSITY OF CALIFORNIA LOS ANGELES Final...2010 To 12-31-2014 4. TITLE AND SUBTITLE GENOME ANNOTATION AND TRANSCRIPTOMICS OF OIL-PRODUCING ALGAE 5a. CONTRACT NUMBER FA9550-10-1-0095 5b...NOTES 14. ABSTRACT Most algae accumulate triacylglycerols (TAGs) when they are starved for essential nutrients like N, S, P (or Si in the case of some

  9. Accumulation of 210Po by benthic marine algae

    International Nuclear Information System (INIS)

    Gouvea, R.C.; Branco, M.E.C.; Santos, P.L.

    1988-01-01

    The accumulation of polonium 210 Po by various species of benthic marine seaweeds collected from 4 different points on the coast of Rio de Janeiro, showed variations by species and algal groups. The highest value found was in red alga, Plocamium brasiliensis followed by other organisms of the same group. In the group of the brown alga, the specie Sargassum stenophylum was outstanding. The Chlorophyta presented the lowest content of 210 Po. The algae collected in open sea, revealed greater concentration factors of 210 Po than the same species living in bays. The siliceous residue remaining after mineralization of the algae did not interfere with the detection of polonium. (author)

  10. Algae Bioreactor Using Submerged Enclosures with Semi-Permeable Membranes

    Science.gov (United States)

    Trent, Jonathan D (Inventor); Gormly, Sherwin J (Inventor); Embaye, Tsegereda N (Inventor); Delzeit, Lance D (Inventor); Flynn, Michael T (Inventor); Liggett, Travis A (Inventor); Buckwalter, Patrick W (Inventor); Baertsch, Robert (Inventor)

    2013-01-01

    Methods for producing hydrocarbons, including oil, by processing algae and/or other micro-organisms in an aquatic environment. Flexible bags (e.g., plastic) with CO.sub.2/O.sub.2 exchange membranes, suspended at a controllable depth in a first liquid (e.g., seawater), receive a second liquid (e.g., liquid effluent from a "dead zone") containing seeds for algae growth. The algae are cultivated and harvested in the bags, after most of the second liquid is removed by forward osmosis through liquid exchange membranes. The algae are removed and processed, and the bags are cleaned and reused.

  11. Importance of algae oil as a source of biodiesel

    International Nuclear Information System (INIS)

    Demirbas, Ayhan; Fatih Demirbas, M.

    2011-01-01

    Algae are the fastest-growing plants in the world. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae are very important as a biomass source. Algae will some day be competitive as a source for biofuel. Different species of algae may be better suited for different types of fuel. Algae can be grown almost anywhere, even on sewage or salt water, and does not require fertile land or food crops, and processing requires less energy than the algae provides. Algae can be a replacement for oil based fuels, one that is more effective and has no disadvantages. Algae are among the fastest-growing plants in the world, and about 50% of their weight is oil. This lipid oil can be used to make biodiesel for cars, trucks, and airplanes. Microalgae have much faster growth-rates than terrestrial crops. the per unit area yield of oil from algae is estimated to be from 20,000 to 80,000 l per acre, per year; this is 7-31 times greater than the next best crop, palm oil. The lipid and fatty acid contents of microalgae vary in accordance with culture conditions. Most current research on oil extraction is focused on microalgae to produce biodiesel from algal oil. Algal-oil processes into biodiesel as easily as oil derived from land-based crops.

  12. Method and apparatus for lysing and processing algae

    Science.gov (United States)

    Chew, Geoffrey; Reich, Alton J.; Dykes, Jr., H. Waite H.; Di Salvo, Roberto

    2013-03-05

    Methods and apparatus for processing algae are described in which a hydrophilic ionic liquid is used to lyse algae cells at lower temperatures than existing algae processing methods. A salt or salt solution is used as a separation agent and to remove water from the ionic liquid, allowing the ionic liquid to be reused. The used salt may be dried or concentrated and reused. The relatively low lysis temperatures and recycling of the ionic liquid and salt reduce the environmental impact of the algae processing while providing biofuels and other useful products.

  13. Chloroplast division checkpoint in eukaryotic algae

    Science.gov (United States)

    Sumiya, Nobuko; Fujiwara, Takayuki; Era, Atsuko; Miyagishima, Shin-ya

    2016-01-01

    Chloroplasts evolved from a cyanobacterial endosymbiont. It is believed that the synchronization of endosymbiotic and host cell division, as is commonly seen in existing algae, was a critical step in establishing the permanent organelle. Algal cells typically contain one or only a small number of chloroplasts that divide once per host cell cycle. This division is based partly on the S-phase–specific expression of nucleus-encoded proteins that constitute the chloroplast-division machinery. In this study, using the red alga Cyanidioschyzon merolae, we show that cell-cycle progression is arrested at the prophase when chloroplast division is blocked before the formation of the chloroplast-division machinery by the overexpression of Filamenting temperature-sensitive (Fts) Z2-1 (Fts72-1), but the cell cycle progresses when chloroplast division is blocked during division-site constriction by the overexpression of either FtsZ2-1 or a dominant-negative form of dynamin-related protein 5B (DRP5B). In the cells arrested in the prophase, the increase in the cyclin B level and the migration of cyclin-dependent kinase B (CDKB) were blocked. These results suggest that chloroplast division restricts host cell-cycle progression so that the cell cycle progresses to the metaphase only when chloroplast division has commenced. Thus, chloroplast division and host cell-cycle progression are synchronized by an interactive restriction that takes place between the nucleus and the chloroplast. In addition, we observed a similar pattern of cell-cycle arrest upon the blockage of chloroplast division in the glaucophyte alga Cyanophora paradoxa, raising the possibility that the chloroplast division checkpoint contributed to the establishment of the permanent organelle. PMID:27837024

  14. Interactions between arsenic species and marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Sanders, J.G.

    1978-01-01

    The arsenic concentration and speciation of marine algae varies widely, from 0.4 to 23 ng.mg/sup -1/, with significant differences in both total arsenic content and arsenic speciation occurring between algal classes. The Phaeophyceae contain more arsenic than other algal classes, and a greater proportion of the arsenic is organic. The concentration of inorganic arsenic is fairly constant in macro-algae, and may indicate a maximum level, with the excess being reduced and methylated. Phytoplankton take up As(V) readily, and incorporate a small percentage of it into the cell. The majority of the As(V) is reduced, methylated, and released to the surrounding media. The arsenic speciation in phytoplankton and Valonia also changes when As(V) is added to cultures. Arsenate and phosphate compete for uptake by algal cells. Arsenate inhibits primary production at concentrations as low as 5 ..mu..g.1/sup -1/ when the phosphate concentration is low. The inhibition is competitive. A phosphate enrichment of > 0.3 ..mu..M alleviates this inhibition; however, the As(V) stress causes an increase in the cell's phosphorus requirement. Arsenite is also toxic to phytoplankton at similar concentrations. Methylated arsenic species did not affect cell productivity, even at concentrations of 25 ..mu..g.1/sup -1/. Thus, the methylation of As(V) by the cell produces a stable, non-reactive compound which is nontoxic. The uptake and subsequent reduction and methylation of As(V) is a significant factor in determining the arsenic biogeochemistry of productive systems, and also the effect that the arsenic may have on algal productivity. Therefore, the role of marine algae in determining the arsenic speciation of marine systems cannot be ignored. (ERB)

  15. Snow algae and lichen algae differ in their resistance to freezing temperature: An ice nucleation study

    Czech Academy of Sciences Publication Activity Database

    Hajek, J.; Kvíderová, Jana; Worland, R.; Barták, M.; Elster, Josef; Vaczi, P.

    2009-01-01

    Roč. 48, č. 4 (2009), s. 37-38 ISSN 0031-8884. [International Phycological Congress /9./. 02.08.2009-08.08.2009, Tokyo] R&D Projects: GA AV ČR IAA600050702; GA AV ČR KJB601630808 Institutional research plan: CEZ:AV0Z60050516 Keywords : ice nucleation * algae * freezing Subject RIV: EF - Botanics

  16. Ammonium removal using algae-bacteria consortia: the effect of ammonium concentration, algae biomass, and light.

    Science.gov (United States)

    Jia, Huijun; Yuan, Qiuyan

    2018-04-01

    In this study, the effects of ammonium nitrogen concentration, algae biomass concentration, and light conditions (wavelength and intensity) on the ammonium removal efficiency of algae-bacteria consortia from wastewater were investigated. The results indicated that ammonium concentration and light intensity had a significant impact on nitrification. It was found that the highest ammonia concentration (430 mg N/L) in the influent resulted in the highest ammonia removal rate of 108 ± 3.6 mg N/L/days, which was two times higher than the influent with low ammonia concentration (40 mg N/L). At the lowest light intensity of 1000 Lux, algae biomass concentration, light wavelength, and light cycle did not show a significant effect on the performance of algal-bacterial consortium. Furthermore, the ammonia removal rate was approximately 83 ± 1.0 mg N/L/days, which was up to 40% faster than at the light intensity of 2500 Lux. It was concluded that the algae-bacteria consortia can effectively remove nitrogen from wastewater and the removal performance can be stabilized and enhanced using the low light intensity of 1000 Lux that is also a cost-effective strategy.

  17. Toxicity of chlorinated benzenes to marine algae

    Science.gov (United States)

    Ma, Yan-Jun; Wang, Xiu-Lin; Yu, Wei-Jun; Zhang, Li-Jun; Sun, Han-Zhang

    1997-12-01

    Growth of Chlorella marine, Nannochloropsis oculata, Pyramidomonas sp., Platymonas subcordiformis and Phaeodactylum tricornutum exposed to monochlorobenzene (MCB), 1,2-dichlorobenzene (1,2-DCB), 1, 2, 3, 4-tetrachlorobenzene (1, 2, 3, 4-TeCB) and pentachlorobenzene (PeCB) was tested. Tests of 72 h- EC 50 values showed that the toxicity ranged in the order: MCBNannochloropsis oculata < Chlorella marine < Phaeodactylum tricomutum. Study of the QSAR (Quantitative Structure-Activity Relationship) between K OW and toxicity of CBs to marine algae showed good relationships between -log EC 50 and log K OW.

  18. Diterpenes from the Brown Alga Dictyota crenulata

    Directory of Open Access Journals (Sweden)

    Valéria Laneuville Teixeira

    2008-06-01

    Full Text Available The crude extract of the Brazilian brown alga Dictyota crenulata was analyzed by NMR spectroscopy and HRGC-MS techniques. Seven diterpenes were identified: pachydictyol A, dictyodial, 4β-hydroxydictyodial A, 4β-acetoxydictyodial A, isopachydictyol A, dictyol C and dictyotadiol. Xeniane diterpenes have previously been found in D. crenulata from the Pacific Ocean. The results characterize D. crenulata as a species that provides prenylated guaiane (group I and xeniane diterpenes (group III, thus making it a new source of potential antiviral products.

  19. Coping with temperature at the warm edge--patterns of thermal adaptation in the microbial eukaryote Paramecium caudatum.

    Directory of Open Access Journals (Sweden)

    Sascha Krenek

    Full Text Available Ectothermic organisms are thought to be severely affected by global warming since their physiological performance is directly dependent on temperature. Latitudinal and temporal variations in mean temperatures force ectotherms to adapt to these complex environmental conditions. Studies investigating current patterns of thermal adaptation among populations of different latitudes allow a prediction of the potential impact of prospective increases in environmental temperatures on their fitness.In this study, temperature reaction norms were ascertained among 18 genetically defined, natural clones of the microbial eukaryote Paramecium caudatum. These different clones have been isolated from 12 freshwater habitats along a latitudinal transect in Europe and from 3 tropical habitats (Indonesia. The sensitivity to increasing temperatures was estimated through the analysis of clone specific thermal tolerances and by relating those to current and predicted temperature data of their natural habitats. All investigated European clones seem to be thermal generalists with a broad thermal tolerance and similar optimum temperatures. The weak or missing co-variation of thermal tolerance with latitude does not imply local adaptation to thermal gradients; it rather suggests adaptive phenotypic plasticity among the whole European subpopulation. The tested Indonesian clones appear to be locally adapted to the less variable, tropical temperature regime and show higher tolerance limits, but lower tolerance breadths.Due to the lack of local temperature adaptation within the European subpopulation, P. caudatum genotypes at the most southern edge of their geographic range seem to suffer from the predicted increase in magnitude and frequency of summer heat waves caused by climate change.

  20. Long-Term Tracking of Free-Swimming Paramecium caudatum in Viscous Media Using a Curved Sample Chamber

    Directory of Open Access Journals (Sweden)

    Mohiuddin Khan Shourav

    2017-12-01

    Full Text Available It is technically difficult to acquire large-field images under the complexity and cost restrictions of a diagnostic and instant field research purpose. The goal of the introduced large-field imaging system is to achieve a tolerable resolution for detecting microscale particles or objects in the entire image field without the field-curvature effect, while maintaining a cost-effective procedure and simple design. To use a single commercial lens for imaging a large field, the design attempts to fabricate a curved microfluidic chamber. This imaging technique improves the field curvature and distortion at an acceptable level of particle detection. This study examines Paramecium caudatum microswimmers to track their motion dynamics in different viscous media with imaging techniques. In addition, the study found that the average speed for P. caudatum was 60 µm/s, with a standard deviation of ±12 µm/s from microscopic imaging of the original medium of the sample, which leads to a variation of 20% from the average measurement. In contrast, from large-field imaging, the average speeds of P. caudatum were 63 µm/s and 68 µm/s in the flat and curved chambers, respectively, with the same medium viscosity. Furthermore, the standard deviations that were observed were ±7 µm/s and ±4 µm/s and the variations from the average speed were calculated as 11% and 5.8% for the flat and curved chambers, respectively. The proposed methodology can be applied to measure the locomotion of the microswimmer at small scales with high precision.

  1. “Candidatus Gortzia shahrazadis”, a novel endosymbiont of Paramecium multimicronucleatum and a revision of the biogeographical distribution of Holospora-like bacteria

    Directory of Open Access Journals (Sweden)

    Valentina Serra

    2016-11-01

    Full Text Available Holospora spp. and Candidatus Gortzia infectiva, known as Holospora-like bacteria (HLB, are commonly found as nuclear endosymbionts of ciliates, especially the Paramecium genus. HLB are related by phylogenetic relationships, morphological features, and life cycles, which involve two alternating morphotypes: reproductive and infectious forms (RF, IF. In this paper we describe a novel species belonging to the Ca. Gortzia genus, detected in P. multimicronucleatum, a ciliate for which infection by an HLB has not been reported, discovered in India. This novel endosymbiont shows unusual and surprising features with respect to other HLB, such as large variations in IF morphology and the occasional ability to reproduce in the host cytoplasm. We propose the name of Candidatus Gortzia shahrazadis for this novel HLB . Moreover, we report two additional species of HLB from Indian Paramecium populations: Ca. Gortzia infectiva (from P. jenningsi, and H. obtusa (from P. caudatum; the latter is the first record of Holospora from a tropical country. Although tropical, we retrieved H. obtusa at an elevation of 706 m. corresponding to a moderate climate not unlike conditions where Holospora are normally found, suggesting the genus Holospora does exist in tropical countries, but restricted to higher elevations.

  2. The protozoan, Paramecium primaurelia, as a non-sentient model to test laser light irradiation: The effects of an 808nm infrared laser diode on cellular respiration.

    Science.gov (United States)

    Amaroli, Andrea; Ravera, Silvia; Parker, Steven; Panfoli, Isabella; Benedicenti, Alberico; Benedicenti, Stefano

    2015-07-01

    Photobiomodulation (PBM) has been used in clinical practice for more than 40 years. Unfortunately, conflicting literature has led to the labelling of PBM as a complementary or alternative medicine approach. However, past and ongoing clinical and research studies by reputable investigators have re-established the merits of PBM as a genuine medical therapy, and the technique has, in the last decade, seen an exponential increase in the numbers of clinical instruments available, and their applications. This resurgence has led to a clear need for appropriate experimental models to test the burgeoning laser technology being developed for medical applications. In this context, an ethical model that employs the protozoan, Paramecium primaurelia, is proposed. We studied the possibility of using the measure of oxygen consumption to test PBM by irradiation with an infrared or near-infrared laser. The results show that an 808nm infrared laser diode (1W; 64J/cm²) affects cellular respiration in P. primaurelia, inducing, in the irradiated cells, a significantly (p Paramecium can be an excellent tool in biological assays involving infrared and near-infrared PBM, as it combines the advantages of in vivo results with the practicality of in vitro testing. This test represents a fast, inexpensive and straightforward assay, which offers an alternative to both traditional in vivo testing and more expensive mammalian cellular cultures. 2015 FRAME.

  3. “Candidatus Gortzia shahrazadis”, a Novel Endosymbiont of Paramecium multimicronucleatum and a Revision of the Biogeographical Distribution of Holospora-Like Bacteria

    Science.gov (United States)

    Serra, Valentina; Fokin, Sergei I.; Castelli, Michele; Basuri, Charan K.; Nitla, Venkatamahesh; Verni, Franco; Sandeep, Bhagavatula V.; Kalavati, Chaganti; Petroni, Giulio

    2016-01-01

    Holospora spp. and “Candidatus Gortzia infectiva”, known as Holospora-like bacteria (HLB), are commonly found as nuclear endosymbionts of ciliates, especially the Paramecium genus. HLB are related by phylogenetic relationships, morphological features, and life-cycles, which involve two alternating morphotypes: reproductive and infectious forms (RF, IF). In this paper we describe a novel species belonging to the “Ca. Gortzia” genus, detected in P. multimicronucleatum, a ciliate for which infection by an HLB has not been reported, discovered in India. This novel endosymbiont shows unusual and surprising features with respect to other HLB, such as large variations in IF morphology and the occasional ability to reproduce in the host cytoplasm. We propose the name of “Candidatus Gortzia shahrazadis” for this novel HLB. Moreover, we report two additional species of HLB from Indian Paramecium populations: “Ca. Gortzia infectiva” (from P. jenningsi), and H. obtusa (from P. caudatum); the latter is the first record of Holospora from a tropical country. Although tropical, we retrieved H. obtusa at an elevation of 706 m corresponding to a moderate climate not unlike conditions where Holospora are normally found, suggesting the genus Holospora does exist in tropical countries, but restricted to higher elevations. PMID:27867371

  4. Bug22p, a conserved centrosomal/ciliary protein also present in higher plants, is required for an effective ciliary stroke in Paramecium.

    Science.gov (United States)

    Laligné, C; Klotz, C; de Loubresse, N Garreau; Lemullois, M; Hori, M; Laurent, F X; Papon, J F; Louis, B; Cohen, J; Koll, F

    2010-04-01

    Centrioles, cilia, and flagella are ancestral conserved organelles of eukaryotic cells. Among the proteins identified in the proteomics of ciliary proteins in Paramecium, we focus here on a protein, Bug22p, previously detected by cilia and basal-body high-throughput studies but never analyzed per se. Remarkably, this protein is also present in plants, which lack centrioles and cilia. Bug22p sequence alignments revealed consensus positions that distinguish species with centrioles/cilia from plants. In Paramecium, antibody and green fluorescent protein (GFP) fusion labeling localized Bug22p in basal bodies and cilia, and electron microscopy immunolabeling refined the localization to the terminal plate of the basal bodies, the transition zone, and spots along the axoneme, preferentially between the membrane and the microtubules. RNA interference (RNAi) depletion of Bug22p provoked a strong decrease in swimming speed, followed by cell death after a few days. High-speed video microscopy and morphological analysis of Bug22p-depleted cells showed that the protein plays an important role in the efficiency of ciliary movement by participating in the stroke shape and rigidity of cilia. The defects in cell swimming and growth provoked by RNAi can be complemented by expression of human Bug22p. This is the first reported case of complementation by a human gene in a ciliate.

  5. Paramecium tetraurelia chromatin assembly factor-1-like protein PtCAF-1 is involved in RNA-mediated control of DNA elimination.

    Science.gov (United States)

    Ignarski, Michael; Singh, Aditi; Swart, Estienne C; Arambasic, Miroslav; Sandoval, Pamela Y; Nowacki, Mariusz

    2014-10-29

    Genome-wide DNA remodelling in the ciliate Paramecium is ensured by RNA-mediated trans-nuclear crosstalk between the germline and the somatic genomes during sexual development. The rearrangements include elimination of transposable elements, minisatellites and tens of thousands non-coding elements called internally eliminated sequences (IESs). The trans-nuclear genome comparison process employs a distinct class of germline small RNAs (scnRNAs) that are compared against the parental somatic genome to select the germline-specific subset of scnRNAs that subsequently target DNA elimination in the progeny genome. Only a handful of proteins involved in this process have been identified so far and the mechanism of DNA targeting is unknown. Here we describe chromatin assembly factor-1-like protein (PtCAF-1), which we show is required for the survival of sexual progeny and localizes first in the parental and later in the newly developing macronucleus. Gene silencing shows that PtCAF-1 is required for the elimination of transposable elements and a subset of IESs. PTCAF-1 depletion also impairs the selection of germline-specific scnRNAs during development. We identify specific histone modifications appearing during Paramecium development which are strongly reduced in PTCAF-1 depleted cells. Our results demonstrate the importance of PtCAF-1 for the epigenetic trans-nuclear cross-talk mechanism. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. Bug22p, a Conserved Centrosomal/Ciliary Protein Also Present in Higher Plants, Is Required for an Effective Ciliary Stroke in Paramecium ▿ †

    Science.gov (United States)

    Laligné, C.; Klotz, C.; Garreau de Loubresse, N.; Lemullois, M.; Hori, M.; Laurent, F. X.; Papon, J. F.; Louis, B.; Cohen, J.; Koll, F.

    2010-01-01

    Centrioles, cilia, and flagella are ancestral conserved organelles of eukaryotic cells. Among the proteins identified in the proteomics of ciliary proteins in Paramecium, we focus here on a protein, Bug22p, previously detected by cilia and basal-body high-throughput studies but never analyzed per se. Remarkably, this protein is also present in plants, which lack centrioles and cilia. Bug22p sequence alignments revealed consensus positions that distinguish species with centrioles/cilia from plants. In Paramecium, antibody and green fluorescent protein (GFP) fusion labeling localized Bug22p in basal bodies and cilia, and electron microscopy immunolabeling refined the localization to the terminal plate of the basal bodies, the transition zone, and spots along the axoneme, preferentially between the membrane and the microtubules. RNA interference (RNAi) depletion of Bug22p provoked a strong decrease in swimming speed, followed by cell death after a few days. High-speed video microscopy and morphological analysis of Bug22p-depleted cells showed that the protein plays an important role in the efficiency of ciliary movement by participating in the stroke shape and rigidity of cilia. The defects in cell swimming and growth provoked by RNAi can be complemented by expression of human Bug22p. This is the first reported case of complementation by a human gene in a ciliate. PMID:20118210

  7. An ion-current mutant of Paramecium tetraurelia with defects in the primary structure and post-translational N-methylation of calmodulin

    International Nuclear Information System (INIS)

    Wallen-Friedman, M.A.

    1988-01-01

    My work on pantophobiac A 2 (pntA 2 ), a behavioral mutant of Paramecium tetraurelia, suggest that the Ca ++ -binding protein calmodulin (CaM), and post-translation N-methylation of CaM, are important for Ca ++ -related ion-current function. Calmodulin from wild-type Paramecium has two sites of lysine-N-methylation. Both of these sites are almost fully methylated in vivo; thus wild-type calmodulin is a poor substrate for N-methylation in vitro. In contrast, pntA/ 2 CaM can be heavily N-methylated in vitro, suggesting that the mutant calmodulin is under-methylated in vivo. Amino-acid composition analysis showed that CaM lysine 115 is undermethylated in pntA 2 . Once pntA 2 CaM is N-methylated, the [methyl- 3 H] group does not turn over in either wild-type or pntA 2 cytoplasmic fractions. The methylating enzymes in pntA 2 high-speed supernatant fractions are active, but may be less robust than those of the wild type, suggesting a possible control of these enzymes by CaM

  8. An ion-current mutant of Paramecium tetraurelia with defects in the primary structure and post-translational N-methylation of calmodulin

    Energy Technology Data Exchange (ETDEWEB)

    Wallen-Friedman, M.A.

    1988-01-01

    My work on pantophobiac A{sup 2} (pntA{sup 2}), a behavioral mutant of Paramecium tetraurelia, suggest that the Ca{sup ++}-binding protein calmodulin (CaM), and post-translation N-methylation of CaM, are important for Ca{sup ++}-related ion-current function. Calmodulin from wild-type Paramecium has two sites of lysine-N-methylation. Both of these sites are almost fully methylated in vivo; thus wild-type calmodulin is a poor substrate for N-methylation in vitro. In contrast, pntA/{sup 2} CaM can be heavily N-methylated in vitro, suggesting that the mutant calmodulin is under-methylated in vivo. Amino-acid composition analysis showed that CaM lysine 115 is undermethylated in pntA{sup 2}. Once pntA{sup 2} CaM is N-methylated, the (methyl-{sup 3}H) group does not turn over in either wild-type or pntA{sup 2} cytoplasmic fractions. The methylating enzymes in pntA{sup 2} high-speed supernatant fractions are active, but may be less robust than those of the wild type, suggesting a possible control of these enzymes by CaM.

  9. Paramecium putrinum (Ciliophora, Protozoa): the first insight into the variation of two DNA fragments - molecular support for the existence of cryptic species.

    Science.gov (United States)

    Tarcz, Sebastian; Rautian, Maria; Potekhin, Alexey; Sawka, Natalia; Beliavskaya, Alexandra; Kiselev, Andrey; Nekrasova, Irina; Przyboś, Ewa

    2014-04-01

    Paramecium putrinum (Claparede & Lachmann 1858) is one of the smallest (80-140 μm long) species of the genus Paramecium. Although it commonly occurs in freshwater reservoirs, no molecular studies of P. putrinum have been conducted to date. Herein we present an assessment of molecular variation in 27 strains collected from widely separated populations by using two selected DNA fragments (ITS1-5.8S-ITS2-5'LSU rDNA and COI mtDNA). Both the trees and haplotype networks reconstructed for both genome fragments show that the studied strains of P. putrinum form five main haplogroups. The mean distance between the studied strains is p-distance=0.007/0.068 (rDNA/COI) and exhibits similar variability as that between P. bursaria syngens. Based on these data, one could hypothesize that the clusters revealed in the present study may correspond to previously reported syngens and that there are at least five cryptic species within P. putrinum. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Effect of 808 nm Diode Laser on Swimming Behavior, Food Vacuole Formation and Endogenous ATP Production of Paramecium primaurelia (Protozoa).

    Science.gov (United States)

    Amaroli, Andrea; Ravera, Silvia; Parker, Steven; Panfoli, Isabella; Benedicenti, Alberico; Benedicenti, Stefano

    2015-01-01

    Photobiomodulation (PBM) has been used in clinical practice for more than 40 years. To clarify the mechanisms of action of PBM at cellular and organism levels, we investigated its effect on Paramecium primaurelia (Protozoa) irradiated by an 808 nm infrared diode laser with a flat-top handpiece (1 W in CW). Our results led to the conclusion that: (1) the 808 nm laser stimulates the P. primaurelia without a thermal effect, (2) the laser effect is demonstrated by an increase in swimming speed and in food vacuole formation, (3) the laser treatment affects endogenous adenosine triphosphate (ATP) production in a positive way, (4) the effects of irradiation dose suggest an optimum exposure time of 50 s (64 J cm(-2) of fluence) to stimulate the Paramecium cells; irradiation of 25 s shows no effect or only mild effects and irradiation up to 100 s does not increase the effect observed with 50 s of treatment, (5) the increment of endogenous ATP concentration highlights the positive photobiomodulating effect of the 808 nm laser and the optimal irradiation conditions by the flat-top handpiece. © 2015 The American Society of Photobiology.

  11. Algae-based oral recombinant vaccines

    Directory of Open Access Journals (Sweden)

    Elizabeth A Specht

    2014-02-01

    Full Text Available Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for molecular pharming in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae are poised to become the next candidate in recombinant subunit vaccine production, and they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally-delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered – from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and system immune reactivity.

  12. Energy from algae using microbial fuel cells

    KAUST Repository

    Velasquez-Orta, Sharon B.

    2009-08-15

    Bioelectricity production froma phytoplankton, Chlorella vulgaris, and a macrophyte, Ulva lactuca was examined in single chamber microbial fuel cells (MFCs). MFCs were fed with the two algae (as powders), obtaining differences in energy recovery, degradation efficiency, and power densities. C. vulgaris produced more energy generation per substrate mass (2.5 kWh/kg), but U. lactuca was degraded more completely over a batch cycle (73±1% COD). Maximum power densities obtained using either single cycle or multiple cycle methods were 0.98 W/m2 (277 W/m3) using C. vulgaris, and 0.76 W/m2 (215 W/m3) using U. lactuca. Polarization curves obtained using a common method of linear sweep voltammetry (LSV) overestimated maximum power densities at a scan rate of 1 mV/s. At 0.1 mV/s, however, the LSV polarization data was in better agreement with single- and multiple-cycle polarization curves. The fingerprints of microbial communities developed in reactors had only 11% similarity to inocula and clustered according to the type of bioprocess used. These results demonstrate that algae can in principle, be used as a renewable source of electricity production in MFCs. © 2009 Wiley Periodicals, Inc.

  13. Algae-based oral recombinant vaccines

    Science.gov (United States)

    Specht, Elizabeth A.; Mayfield, Stephen P.

    2014-01-01

    Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for “molecular pharming” in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae could be poised to become the next candidate in recombinant subunit vaccine production, as they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered – from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and systemic immune reactivity. PMID:24596570

  14. Isolation and Characterization of Blue Green Algae from Egyptian ...

    African Journals Online (AJOL)

    meldemellawy

    2014-02-20

    Feb 20, 2014 ... aminotransferase (AMT) domains of the mycE and ndaF genes (Jungblut et al., 2006) allowing detection of microcystin and nodularin-producing cyanobacteria. MATERIALS AND METHODS. Isolation and cultivation of blue green algae. Blue green algae had been isolated from soil of Rice field in river.

  15. Monetary value of the impacts of filamentous green algae on ...

    African Journals Online (AJOL)

    This paper presents estimates of the monetary value of the impact of eutrophication (algae) on commercial agriculture in two different catchments in South Africa. A production function approach is applied to estimate the monetary value of the impact of filamentous green algae on commercial agriculture in the Dwars River, ...

  16. Dissolved Air Flotation Process for Algae Removal | Mulaku ...

    African Journals Online (AJOL)

    This study investigated the performance of the Dissolved Air Flotation (DAF) process as an alternative to sedimentation for algae removal in surface water treatment in Kenya. Batch DAF experiments were carried out in the laboratory using algae laden surface water samples collected from the river and laboratory cultured ...

  17. Persistence and proliferation of some unicellular algae in drinking ...

    African Journals Online (AJOL)

    Drinking water systems have a complex structure and are characterised by the absence of light, the presence of disinfectants and by low levels of nutrients. Several kinds of bacteria, protozoa, algae and fungi can be found in tap water. Little is known about the ecology of algae in drinking water systems, although their ...

  18. Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    The Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report summarizes a workshop hosted by the U.S. Department of Energy's Bioenergy Technologies Office on May 23–24, 2017, in Orlando, Florida. The event gathered stakeholder input through facilitated discussions focused on innovative technologies and business strategies for growing algae on waste carbon dioxide resources.

  19. Study on the effect of irradiation on algae by proteomics

    International Nuclear Information System (INIS)

    Choi, Jong Il; Yoon, Yo Han; Kim, Jae Hun

    2010-06-01

    Algae has been utilized as food material from long time ago, and recently newly recognized as functional materials and the source of bio-fuel. But, the study on the algae is just beginning and the study on protein expression and growth by the change of condition was not reported. In this study, the effect of radiation on the protein expression was investigated for the protection mechanisms and new genome source and furthermore, isolation of new mutant strains. To monitor the growth of algae, absorbance and FDA staining methods were developed and the content of lipid of algae species were measured. With these methods, the radiation sensitivity of algae species was determined. To investigate the proteome of algae, 2D-electrophoresis methods was applied. From the comparison of proteomes, the radiation specific expressed protein was identified as thioredoxin-h and its nucleotide sequences was defined. The expression of thioredoxin-h was further defined on the mRNA level. Also, the extract of algae species was analyzed for its antioxidant activity and polyphenolic content. The changes in antioxidant activity of extract by radiation was investigated. From the radiation experiments, mutant Spirogyra species having higher resistant against radical stress was obtained. The mutant strain has higher antioxidant activity. This results can provide the proteome date and mutation technology of algae and further contribute in the activation of fishery industry and national health enhancement

  20. EnAlgae Decision Support Toolset: model validation

    NARCIS (Netherlands)

    Kenny, Philip; Visser, de Chris; Skarka, Johannes; Sternberg, Kirstin; Schipperus, Roelof; Silkina, Alla; Ginnever, Naomi

    2015-01-01

    One of the drivers behind the EnAlgae project is recognising and addressing the need for increased availability of information about developments in applications of algae biotechnology for energy, particularly in the NW Europe area, where activity has been less intense than in other areas of the

  1. Evaluation of the activated carbon prepared from the algae ...

    African Journals Online (AJOL)

    Evaluation of the activated carbon prepared from the algae Gracilaria for the biosorption of Cu(II) from aqueous solutions. ... African Journal of Biotechnology ... This study shows the benefit of using activated carbon from marine red algae as a low cost sorbent for the removal of copper from aqueous solution wastewater.

  2. Potential of wastewater grown algae for biodiesel production and CO

    African Journals Online (AJOL)

    Potential of wastewater grown algae for biodiesel production and CO 2 sequestration. ... African Journal of Biotechnology ... Mixed algae sample showed the highest CO2 fixation rate, followed by Chlorella sp., Scenedesmus incrassatulus, Scenedesmus dimorphus and Chroococcus cohaerens (2.807, 1.627, 1.501, 1.270 ...

  3. Rare species of fungi parasiting on algae. III.

    Directory of Open Access Journals (Sweden)

    Joanna Z. Kadłubowska

    2014-08-01

    Full Text Available The investigations csrried out on algae revealed the following species of fungi from the order of Chytridialis Hawksworth et al. (1995 parasitizing on algae: Rhizophydium subgulosum, R. ganlosporum, R. planctonicum, Entophlyctis rhizina and Harpochytrium hedinii. These species arc new to Poland. The figure of resting spore of Entophlyctis rhizina is the fint graphic documentation of this species.

  4. Rare species of fungi parasiting on algae. III.

    OpenAIRE

    Joanna Z. Kadłubowska

    2014-01-01

    The investigations csrried out on algae revealed the following species of fungi from the order of Chytridialis Hawksworth et al. (1995) parasitizing on algae: Rhizophydium subgulosum, R. ganlosporum, R. planctonicum, Entophlyctis rhizina and Harpochytrium hedinii. These species arc new to Poland. The figure of resting spore of Entophlyctis rhizina is the fint graphic documentation of this species.

  5. Recent Advances in Marine Algae Polysaccharides: Isolation, Structure, and Activities.

    Science.gov (United States)

    Xu, Shu-Ying; Huang, Xuesong; Cheong, Kit-Leong

    2017-12-13

    Marine algae have attracted a great deal of interest as excellent sources of nutrients. Polysaccharides are the main components in marine algae, hence a great deal of attention has been directed at isolation and characterization of marine algae polysaccharides because of their numerous health benefits. In this review, extraction and purification approaches and chemico-physical properties of marine algae polysaccharides (MAPs) are summarized. The biological activities, which include immunomodulatory, antitumor, antiviral, antioxidant, and hypolipidemic, are also discussed. Additionally, structure-function relationships are analyzed and summarized. MAPs' biological activities are closely correlated with their monosaccharide composition, molecular weights, linkage types, and chain conformation. In order to promote further exploitation and utilization of polysaccharides from marine algae for functional food and pharmaceutical areas, high efficiency, and low-cost polysaccharide extraction and purification methods, quality control, structure-function activity relationships, and specific mechanisms of MAPs activation need to be extensively investigated.

  6. Investigation about Role of Algae in Kazeroon Sasan Spring Odor

    Directory of Open Access Journals (Sweden)

    A Hamzeian

    2016-05-01

    Full Text Available Introduction: As odor for potable water is unpleasant for costumers, it needs to do researches for finding the reasons of odorous water. Sasan spring that is located in, near kazeroon city, Fars, Iran, is potable water resource for Kazeroon and Booshehr city and many other villages. Water in Sasan spring has the odor problem. With regards to important   role of algae on ado r problems in this study the role of algae on   odor was investigated. Methods: After regular sampling, the TON (threshold odor number was indicated and algae species was distinguished and the number of total algae and any species  of algae was numbers by microscopic direct numbering method .as the algae mass  is related to nitrogen and phosphor concentration, results of concentration Of nitrogen and phosphor in this spring that was examined regularity by water company was investigated and compared to concentration of these component that are need for algae growing.   Results: results shows that TON was in range  of 4.477 to 6.2 that indicated  oderous limit . Regression and diagram between TON and number of total algae showed the linear relationship. The concentration of nitrogen and phosphor, showed adequate condition for algal grow. Result of determination of algae species showed high population of Oscilatoria and Microcystis species, which are known as essential case of mold odor in water resources. Investigation on geological maps in the region around the Sasan spring, show alluvium source and is effected by surface part of it’s around land. Conclusion: because of the algae was determined as the essential cause of odor   in the spring, and algal growth is related to nutrients, and because of the surface pollution can penetrate in the alluvium lands around the spring, and effect the water in spring, so nutrient control and management is the essential way for odor control in the spring.

  7. Phycobiliproteins: A Novel Green Tool from Marine Origin Blue-Green Algae and Red Algae.

    Science.gov (United States)

    Chandra, Rashmi; Parra, Roberto; Iqbal, Hafiz M N

    2017-01-01

    Marine species are comprising about a half of the whole global biodiversity; the sea offers an enormous resource for novel bioactive compounds. Several of the marine origin species show multifunctional bioactivities and characteristics that are useful for a discovery and/or reinvention of biologically active compounds. For millennia, marine species that includes cyanobacteria (blue-green algae) and red algae have been targeted to explore their enormous potential candidature status along with a wider spectrum of novel applications in bio- and non-bio sectors of the modern world. Among them, cyanobacteria are photosynthetic prokaryotes, phylogenetically a primitive group of Gramnegative prokaryotes, ranging from Arctic to Antarctic regions, capable of carrying out photosynthesis and nitrogen fixation. In the recent decade, a great deal of research attention has been paid on the pronouncement of bio-functional proteins along with novel peptides, vitamins, fine chemicals, renewable fuel and bioactive compounds, e.g., phycobiliproteins from marine species, cyanobacteria and red algae. Interestingly, they are extensively commercialized for natural colorants in food and cosmetics, antimicrobial, antioxidant, anti-inflammatory, neuroprotective, hepatoprotective agents and fluorescent neo-glycoproteins as probes for single particle fluorescence imaging fluorescent applications in clinical and immunological analysis. However, a comprehensive knowledge and technological base for augmenting their commercial utilities are lacking. Therefore, this paper will provide an overview of the phycobiliproteins-based research literature from marine cyanobacteria and red algae. This review is also focused towards analyzing global and commercial activities with application oriented-based research. Towards the end, the information is also given on the potential biotechnological and biomedical applications of phycobiliproteins. Copyright© Bentham Science Publishers; For any queries, please

  8. Antileishmanial properties of tropical marine algae extracts.

    Science.gov (United States)

    Freile-Pelegrin, Y; Robledo, D; Chan-Bacab, M J; Ortega-Morales, B O

    2008-07-01

    Aqueous and organic extracts of twenty-seven species of marine algae (14 species of Rhodophyta, 5 species of Phaeophyta and 8 species of Chlorophyta) collected from the Gulf of Mexico and Caribbean coast of the Yucatan Peninsula (Mexico) were evaluated for their antileishmanial in vitro activity against Leishmania mexicana promastigote forms. The cytotoxicity of these extracts was also assessed using brine shrimp. Organic extracts from Laurencia microcladia (Rhodophyta), Dictyota caribaea, Turbinaria turbinata and Lobophora variegata (Phaeophyta) possessed promising in vitro activity against L. mexicana promastigotes (LC(50) values ranging from 10.9 to 49.9 microg/ml). No toxicity of algal extracts against Artemia salina was observed with LC50 ranging from 119 to >or=1000 microg/ml. Further studies on bio-guided fractionation, isolation and characterization of pure compounds from these species as well as in vivo experiments are needed and are already in progress.

  9. An algae-covered alligator rests warily

    Science.gov (United States)

    2000-01-01

    An algae-covered alligator keeps a wary eye open as it rests in one of the ponds at Kennedy Space Center. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Center shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  10. Harmful impact of filamentous algae (Spirogyra sp. on juvenile crayfish

    Directory of Open Access Journals (Sweden)

    Ulikowski Dariusz

    2015-12-01

    Full Text Available The aim of this study was to determine the impact of filamentous algae on the growth and survival of juvenile narrow-clawed crayfish, Astacus leptodactylus (Esch., in rearing basins. Three stocking variants were used: A - basins with a layer of filamentous algae without imitation mineral substrate; B - basins with a layer of filamentous algae with imitation mineral substrate; C - basins without filamentous algae but with mineral substrate. The crayfish were reared from June 12 to October 10 under natural thermal conditions and fed a commercial feed. The results indicated that the presence of the filamentous algae did not have a statistically significant impact on the growth of the juvenile crayfish (P > 0.05. The presence of the filamentous algae had a strong negative impact on juvenile crayfish survival and stock biomass (P < 0.05. The layer of gravel and small stones that imitated the mineral substrate of natural aquatic basins somewhat neutralized the disadvantageous impact the filamentous algae had on the crayfish.

  11. A screening method for cardiovascular active compounds in marine algae.

    Science.gov (United States)

    Agatonovic-Kustrin, S; Kustrin, E; Angove, M J; Morton, D W

    2018-05-18

    The interaction of bioactive compounds from ethanolic extracts of selected marine algae samples, separated on chromatographic plates, with nitric/nitrous acid was investigated. The nature of bioactive compounds in the marine algae extracts was characterised using UV absorption spectra before and after reaction with diluted nitric acid, and from the characteristic colour reaction after derivatization with anisaldehyde. It was found that diterpenes from Dictyota dichotoma, an edible brown algae, and sterols from green algae Caulerpa brachypus, bind nitric oxide and may act as a nitric oxide carrier. Although the carotenoid fucoxanthin, found in all brown marine algae also binds nitric oxide, the bonds between nitrogen and the fucoxanthin molecule are much stronger. Further studies are required to evaluate the effects of diterpenes from Dictyota dichotoma and sterols from green algae Caulerpa brachypus to see if they have beneficial cardiovascular effects. The method reported here should prove useful in screening large numbers of algae species for compounds with cardiovascular activity. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Photophysiology and cellular composition of sea ice algae

    International Nuclear Information System (INIS)

    Lizotte, M.P.

    1989-01-01

    The productivity of sea ice algae depends on their physiological capabilities and the environmental conditions within various microhabitats. Pack ice is the dominant form of sea ice, but the photosynthetic activity of associated algae has rarely been studied. Biomass and photosynthetic rates of ice algae of the Weddell-Scotia Sea were investigated during autumn and winter, the period when ice cover grows from its minimum to maximum. Biomass-specific photosynthetic rates typically ranged from 0.3 to 3.0 μg C · μg chl -1 · h -1 higher than land-fast ice algae but similar to Antarctic phytoplankton. Primary production in the pack ice during winter may be minor compared to annual phytoplankton production, but could represent a vital seasonal contribution to the Antarctic ecosystem. Nutrient supply may limit the productivity of ice algae. In McMurdo Sound, congelation ice algae appeared to be more nutrient deficient than underlying platelet ice algae based on: lower nitrogen:carbon, chlorophyll:carbon, and protein:carbohydrate; and 14 C-photosynthate distribution to proteins and phospholipids was lower, while distribution to polysaccharides and neutral lipids was higher. Depletion of nitrate led to decreased nitrogen:carbon, chlorophyll:carbon, protein:carbohydrate, and 14 C-photosynthate to proteins. Studied were conducted during the spring bloom; therefore, nutrient limitation may only apply to dense ice algal communities. Growth limiting conditions may be alleviated when algae are released into seawater during the seasonal recession of the ice cover. To continue growth, algae must adapt to the variable light field encountered in a mixed water column. Photoadaptation was studied in surface ice communities and in bottom ice communities

  13. Uptake of technetium by marine algae: autoradiographic localization

    Energy Technology Data Exchange (ETDEWEB)

    Bonotto, S.; Nuyts, G.; Robbrecht, V.; Cogneau, M.; Ben, D. van der

    1988-02-01

    The uptake of technetium (sup(95m)Tc) by marine algae was localized by autoradiography. In the brown (Ascophyllum nodosum, Fucus spiralis and F. vesiculosus) as well as in the red (Porphyra umbilicalis) species, the distribution of technetium was heterogeneous, this radioelement being mostly accumulated in the parts of the plant which bear reproductive cells or which contain young tissues. Since brown algae have high concentration factors, they could constitute an important link in the transfer of technetium through the food chain. On the contrary, the edible alga Porphyra umbilicalis shows a very low incorporation of technetium.

  14. Dinitrogen fixation by blue-green algae from paddy fields

    International Nuclear Information System (INIS)

    Thomas, Joseph

    1977-01-01

    Recent work using radioactive nitrogen on the blue-green algae of paddy fields has been reviewed. These algae fix dinitrogen and photoassimilate carbon evolving oxygen, thereby augmenting nitrogen and carbon status of the soil and also providing oxygen to the water-logged rice paddies. Further studies using radioactive isotopes 13 N, 24 Na and 22 Na on their nitrogen fixation, nitrogen assimilation pathways; regulation of nitrogenase, heterocysts production and sporulation and sodium transport and metabolism have been carried out and reported. The field application of blue green algae for N 2 fixation was found to increase the status of soil nitrogen and yield of paddy. (M.G.B.)

  15. Photobiological hydrogen production with switchable photosystem-II designer algae

    Science.gov (United States)

    Lee, James Weifu

    2014-02-18

    A process for enhanced photobiological H.sub.2 production using transgenic alga. The process includes inducing exogenous genes in a transgenic alga by manipulating selected environmental factors. In one embodiment inducing production of an exogenous gene uncouples H.sub.2 production from existing mechanisms that would downregulate H.sub.2 production in the absence of the exogenous gene. In other embodiments inducing an exogenous gene triggers a cascade of metabolic changes that increase H.sub.2 production. In some embodiments the transgenic alga are rendered non-regenerative by inducing exogenous transgenes for proton channel polypeptides that are targeted to specific algal membranes.

  16. The biotechnological ways of blue-green algae complex processing

    OpenAIRE

    Nykyforov, Volodymyr; Malovanyy, Myroslav; Kozlovskaya, Tatyana; Novokhatko, Olha; Digtiar, Sergii

    2016-01-01

    The results of long­term research of various ways and methods of collection and processing of blue­green algae that cause “bloom” of the Dnieper reservoirs were presented. The possibility and feasibility of the blue­green algae biomass processing to biogas by methanogenesis were substantiated. It was found experimentally that preliminary mechanical cavitation of the blue­green algae biomass increases the biogas yield by 21.5 %. It was determined that the biogas produced contains up to 72 % of...

  17. Detection of green algae (Chlorophyceae) for the diagnosis of drowning.

    Science.gov (United States)

    Yoshimura, S; Yoshida, M; Okii, Y; Tokiyasu, T; Watabiki, T; Akane, A

    1995-01-01

    The plankton test (generally, diatom test) is one of the methods available to diagnose the cause of death of submerged bodies. The solubilization method using tissue solubilizer Soluene-350 was used in this study to detect not only diatoms but also green algae, based on the fact that the solubilizer does not digest the cell walls of green algae which are made from cellulose. Detection of green algae from organs of submerged cadavers is very informative to determine drowning in fresh water, and also in cases where only few diatoms are detected in the organs.

  18. DNA barcoding of a new record of epi-endophytic green algae ...

    Indian Academy of Sciences (India)

    Epi-endophytic green algae comprise one of the most diverse and phylogenetically primitive groups of green algae and are considered to be ubiquitous in the world's oceans; however, no reports of these algae exist from India. Here we report the serendipitous discovery of Ulvella growing on intertidal green algae ...

  19. Sterol composition of the Adriatic Sea algae Ulva lactuca, Codium dichotomum, Cystoseira adriatica and Fucus virsoides

    Directory of Open Access Journals (Sweden)

    RADOMIR KAPETANOVIC

    2005-12-01

    Full Text Available The sterol composition of two green algae and two brown algae from the South Adriatic was determined. In the green alga Ulva lactuca, the principal sterols were cholesterol and isofucosterol. In the brown alga Cystoseira adriatica, the main sterols were cholesterol and stigmast-5-en-3ß-ol, while the characteristic sterol of the brown algae, fucosterol, was found only in low concentration. The sterol fractions of the green alga Codium dichotomum and the brown alga Fucus virsoides contained practically only one sterol each, comprising more than 90 % of the total sterols (clerosterol in the former and fucosterol in the latter.

  20. Bicarbonate produced from carbon capture for algae culture.

    Science.gov (United States)

    Chi, Zhanyou; O'Fallon, James V; Chen, Shulin

    2011-11-01

    Using captured CO(2) to grow microalgae is limited by the high cost of CO(2) capture and transportation, as well as significant CO(2) loss during algae culture. Moreover, algae grow poorly at night, but CO(2) cannot be temporarily stored until sunrise. To address these challenges, we discuss a process where CO(2) is captured as bicarbonate and used as feedstock for algae culture, and the carbonate regenerated by the culture process is used as an absorbent to capture more CO(2). This process would significantly reduce carbon capture costs because it does not require additional energy for carbonate regeneration. Furthermore, not only would transport of the aqueous bicarbonate solution cost less than for that of compressed CO(2), but using bicarbonate would also provide a superior alternative for CO(2) delivery to an algae culture system. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Extreme Low Light Requirement for Algae Growth Underneath Sea Ice

    DEFF Research Database (Denmark)

    Hancke, Kasper; Lund-Hansen, Lars C.; Lamare, Maxim L.

    2018-01-01

    Microalgae colonizing the underside of sea ice in spring are a key component of the Arctic foodweb as they drive early primary production and transport of carbon from the atmosphere to the ocean interior. Onset of the spring bloom of ice algae is typically limited by the availability of light......, and the current consensus is that a few tens-of-centimeters of snow is enough to prevent sufficient solar radiation to reach underneath the sea ice. We challenge this consensus, and investigated the onset and the light requirement of an ice algae spring bloom, and the importance of snow optical properties...... for light penetration. Colonization by ice algae began in May under >1 m of first-year sea ice with approximate to 1 m thick snow cover on top, in NE Greenland. The initial growth of ice algae began at extremely low irradiance (...

  2. Kalaärimeeste kohus algas venitamisega / Hindrek Riikoja

    Index Scriptorium Estoniae

    Riikoja, Hindrek

    2007-01-01

    Harju maakohtus algas kohtuprotsess veterinaar- ja toiduameti endise asejuhi Vladimir Razumovski väidetava altkäemaksuvõtmise üle, kus on süüdistavaid eraisikuid ja ettevõtjaid. Lisa: Kes on kohtu all?

  3. Ectocarpus: a model organism for the brown algae.

    Science.gov (United States)

    Coelho, Susana M; Scornet, Delphine; Rousvoal, Sylvie; Peters, Nick T; Dartevelle, Laurence; Peters, Akira F; Cock, J Mark

    2012-02-01

    The brown algae are an interesting group of organisms from several points of view. They are the dominant organisms in many coastal ecosystems, where they often form large, underwater forests. They also have an unusual evolutionary history, being members of the stramenopiles, which are very distantly related to well-studied animal and green plant models. As a consequence of this history, brown algae have evolved many novel features, for example in terms of their cell biology and metabolic pathways. They are also one of only a small number of eukaryotic groups to have independently evolved complex multicellularity. Despite these interesting features, the brown algae have remained a relatively poorly studied group. This situation has started to change over the last few years, however, with the emergence of the filamentous brown alga Ectocarpus as a model system that is amenable to the genomic and genetic approaches that have proved to be so powerful in more classical model organisms such as Drosophila and Arabidopsis.

  4. Potential pharmacological applications of polyphenolic derivatives from marine brown algae.

    Science.gov (United States)

    Thomas, Noel Vinay; Kim, Se-Kwon

    2011-11-01

    Recently, the isolation and characterization of the biologically active components from seaweeds have gained much attention from various research groups across the world. The marine algae have been studied for biologically active components and phlorotannins are one among them. Among marine algae, brown algal species such as Ecklonia cava, Eisenia arborea, Ecklonia stolinifera and Eisenia bicyclis have been studied for their potential biological activities. Majority of the investigations on phlorotannins derived from brown algae have exhibited their potentiality as antioxidant, anti-inflammatory, antidiabetic, antitumor, antihypertensive, anti-allergic, hyaluronidase enzyme inhibition and in matrix metalloproteinases (MMPs) inhibition activity. In this review, we have made an attempt to discuss the potential biological activities of phlorotannins from marine brown algae and their possible candidature in the pharmaceutical applications. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Exploring the potential of using algae in cosmetics.

    Science.gov (United States)

    Wang, Hui-Min David; Chen, Ching-Chun; Huynh, Pauline; Chang, Jo-Shu

    2015-05-01

    The applications of microalgae in cosmetic products have recently received more attention in the treatment of skin problems, such as aging, tanning and pigment disorders. There are also potential uses in the areas of anti-aging, skin-whitening, and pigmentation reduction products. While algae species have already been used in some cosmetic formulations, such as moisturizing and thickening agents, algae remain largely untapped as an asset in this industry due to an apparent lack of utility as a primary active ingredient. This review article focuses on integrating studies on algae pertinent to skin health and beauty, with the purpose of identifying serviceable algae functions in practical cosmetic uses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Chemical examination of the Red alga Acanthophora spicifera

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; Kamat, S.Y.

    Analyses of petroleum ether and chloroform extracts of the marine alga Acanthophora spicifera exhibiting antifertility activity led to the isolation of sterols and fatty acids as well as the rare dipeptides aurantiamides. All the compounds were...

  7. Chemical examination of the brown alga Stoechospermum marginatum (C. Agardh)

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; DeSouza, L.; Kamat, S.Y.

    The crude methalonic extract of marine algae Stoechospermum marginatum from west coast of India was found to have spasmolytic activity. Search for the pharmacologically active compounds led to the isolation of steroids, fatty acids and an ester...

  8. The role of algae in agriculture: a mathematical study.

    Science.gov (United States)

    Tiwari, P K; Misra, A K; Venturino, Ezio

    2017-06-01

    Synthetic fertilizers and livestock manure are nowadays widely used in agriculture to improve crop yield but nitrogen and phosphorous runoff resulting from their use compromises water quality and contributes to eutrophication phenomena in waterbeds within the countryside and ultimately in the ocean. Alternatively, algae could play an important role in agriculture where they can be used as biofertilizers and soil stabilizers. To examine the possible reuse of the detritus generated by dead algae as fertilizer for crops, we develop three mathematical models building upon each other. A system is proposed in which algae recover waste nutrients (nitrogen and phosphorus) for reuse in agricultural production. The results of our study show that in so doing, the crop yield may be increased and simultaneously the density of algae in the lake may be reduced. This could be a way to mitigate and possibly solve the environmental and economic issues nowadays facing agriculture.

  9. Modelization of tritium transfer into the organic compartments of algae

    International Nuclear Information System (INIS)

    Bonotto, S.; Gerber, G.B.; Arapis, G.; Kirchmann, R.

    1982-01-01

    Uptake of tritium oxide and its conversion into organic tritium was studied in four different types of algae with widely varying size and growth characteristics (Acetabularia acetabulum, Boergesenia forbesii, two strains of Chlamydomonas and Dunaliella bioculata). Water in the cell and the vacuales equilibrates rapidly with external tritium water. Tritium is actively incorporated into organically bound form as the organisms grow. During the stationary phase, incorporation of tritium is slow. There exists a discrimination against the incorporation of tritium into organically bound form. A model has been elaborated taking in account these different factors. It appears that transfer of organic tritium by algae growing near the sites of release would be significant only for actively growing algae. Algae growing slowly may, however, be useful as cumulative indicators of discontinuous tritium release. (author)

  10. Scenario analysis of large scale algae production in tubular photobioreactors

    NARCIS (Netherlands)

    Slegers, P.M.; Beveren, van P.J.M.; Wijffels, R.H.; Straten, van G.; Boxtel, van A.J.B.

    2013-01-01

    Microalgae productivity in tubular photobioreactors depends on algae species, location, tube diameter, biomass concentration, distance between tubes and for vertically stacked systems, the number of horizontal tubes per stack. A simulation model for horizontal and vertically stacked horizontal

  11. Studies on allergenic algae of Delhi area: botanical aspects.

    Science.gov (United States)

    Mittal, A; Agarwal, M K; Shivpuri, D N

    1979-04-01

    To study distribution of algae in and around Delhi aerobiological surveys were undertaken for two consecutive years (September, 1972, to August, 1974). The surveys were accomplished by (a) slide exposure method and (b) culture plate exposure method. A total of 850 slides were exposed using Durham's gravity sampling device. Of these, 560 slides were exposed during 1973 (272 slides at two meter and 288 at ten meter height) and the rest (290 slides) were exposed during 1974 at ten meter height. A total of 858 culture plates were exposed (276 for one hour and 282 for two hours) during 1973 and the rest (300 culture plates) were exposed during 1974 at ten meter height for two hours duration only. Air was found to be rich in algae flora during the months of September to November. The dominant forms of algae present were all blue greens. This might be due to the relative greater resistance of blue green algae to unfavorable conditions.

  12. Lab on a chip technologies for algae detection: a review.

    Science.gov (United States)

    Schaap, Allison; Rohrlack, Thomas; Bellouard, Yves

    2012-08-01

    Over the last few decades, lab on a chip technologies have emerged as powerful tools for high-accuracy diagnosis with minute quantities of liquid and as tools for exploring cell properties in general. In this paper, we present a review of the current status of this technology in the context of algae detection and monitoring. We start with an overview of the detection methods currently used for algae monitoring, followed by a review of lab on a chip devices for algae detection and classification, and then discuss a case study based on our own research activities. We conclude with a discussion on future challenges and motivations for algae-oriented lab on a chip technologies. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Molecular aspects of calcium signalling at the crossroads of unikont and bikont eukaryote evolution--the ciliated protozoan Paramecium in focus.

    Science.gov (United States)

    Plattner, Helmut

    2015-03-01

    The ciliated protozoan, Paramecium tetraurelia has a high basic Ca(2+) leakage rate which is counteracted mainly by export through a contractile vacuole complex, based on its V-type H(+)-ATPase activity. In addition Paramecium cells dispose of P-type Ca(2+)-ATPases, i.e. a plasmamembrane and a sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (PMCA, SERCA). Antiporter systems are to be expected, as inferred from indirect evidence. Among the best known cytosolic Ca(2+)-binding proteins, calmodulin activates Ca(2+) influx channels in the somatic cell membrane, but inactivates Ca(2+) influx channels in cilia, where it, thus, ends ciliary reversal induced by depolarization via channels in the somatic cell membrane. Centrin inactivates Ca(2+) signals after stimulation by its high capacity/low affinity binding sites, whereas its high affinity sites regulate some other functions. Cortical Ca(2+) stores (alveolar sacs) are activated during stimulated trichocyst exocytosis and thereby mediate store-operated Ca(2+) entry (SOCE). Ca(2+) release channels (CRCs) localised to alveoli and underlying SOCE are considered as Ryanodine receptor-like proteins (RyR-LPs) which are members of a CRC family with 6 subfamilies. These also encompass genuine inositol 1,4,5-trisphosphate receptors (IP3Rs) and intermediates between the two channel types. All IP3R/RyR-type CRCs possess six carboxyterminal transmembrane domains (TMD), with a pore domain between TMD 5 and 6, endowed with a characteristic selectivity filter. There are reasons to assume a common ancestor molecule for such channels and diversification further on in evolution. The distinct distribution of specific CRCs in the different vesicles undergoing intracellular trafficking suggests constitutive formation of very locally restricted Ca(2+) signals during vesicle-vesicle interaction. In summary, essential steps of Ca(2+) signalling already occur at this level of evolution, including an unexpected multitude of CRCs. For dis

  14. Diversity and ecology of filamentous green conjugate algae

    OpenAIRE

    Strouhalová, Pavla

    2016-01-01

    Filamentous conjugating algae have a cosmopolitan distribution. They often inhabit fragile freshwater habitats such as temporary hydrated ditches or puddles of melting snow. Occurrence in this environment entails having to deal with extreme conditions. That helps them to variously adaptation and also the formation of resistant stages. Algae belonging to this group have an important role in nature, because they are often the first species that inhabit newly created habitats and consequently al...

  15. Cytotoxicity of Algae Extracts on Normal and Malignant Cells

    OpenAIRE

    Bechelli, Jeremy; Coppage, Myra; Rosell, Karen; Liesveld, Jane

    2011-01-01

    Algae preparations are commonly used in alternative medicine. We examined the effects of algae extracts on normal hematopoietic cells and leukemia cells. Ethanol extracts were prepared of Dunaliella salina (Dun), Astaxanthin (Ast), Spirulina platensis (Spir), and Aphanizomenon flos-aquae (AFA). Cell viability effects were completed by Annexin staining. Ast and AFA inhibited HL-60 and MV-4-11 whereas Dun and Spir had no effect. Primary AML blasts demonstrated increased apoptosis in AFA. ...

  16. Algae Reefs in Shark Bay, Western Australia, Australia

    Science.gov (United States)

    1990-01-01

    Numerous algae reefs are seen in Shark Bay, Western Australia, Australia (26.0S, 113.5E) especially in the southern portions of the bay. The south end is more saline because tidal flow in and out of the bay is restricted by sediment deposited at the north and central end of the bay opposite the mouth of the Wooramel River. This extremely arid region produces little sediment runoff so that the waters are very clear, saline and rich in algae.

  17. Thermal algae in certain radioactive springs in Japan, (3)

    International Nuclear Information System (INIS)

    Mifune, Masaaki; Hirose, Hiroyuki.

    1982-01-01

    Shikano Hot Springs are located at five km to the south of Hamamura Station on the Sanin Line in Tottori Prefecture. The water temperature and the pH of the springs are 40.2 - 61.2 0 C, and 7.5 - 7.8, respectively. They belong to simple thermals. Hamamura Hot Springs are located in the neighbourhood of Hamamura Station. The highest radon content of the hot springs is 175.1 x 10 -10 Ci/l, and the great part of the springs belong to radioactive ones. From the viewpoint of the major ionic constituents, they are also classified under weak salt springs, sulfated salt springs, and simple thermals. Regarding the habitates of the algal flora, the water temperature and the pH of the springs are 28.0 - 68.0 0 C, and 6.8 - 7.4, respectively. The thermal algae found by Ikoma and Doi at Hamamura Hot Springs were two species of Cyanophyceae. By the authors, nine species and one variety of Cyanophyceae including Ikoma and Doi's two species were newly found at Shikano and Hamamura Hot Springs. Chlorophyceous alga was not found. The dominant thermal algae of these hot springs were Mastigocladus laminosus, and the other algae which mainly consist of Oscillatoriaceous algae. From these points, it seems that the thermal algae of Shikano and Hamamura Hot Springs belong to the normal type of thermal algae, and they are different from the thermal algae of Ikeda Mineral Springs and Masutomi Hot Springs which belong to strongly radioactive springs. (author)

  18. Using the marine unicellular algae in biological monitoring

    OpenAIRE

    Kapkov V. I.; Shoshina E. V.; Belenikina O. A.

    2017-01-01

    The possibility of using marine unicellular algae from natural plankton community in biomonitoring of pollution by heavy metals has been investigated. Algae of different taxa from the Mediterranean Sea have been allocated to culture. In the laboratory the culture conditions – i. e. growth medium, temperature, photoperiod, level of artificial light and initial density – have been selected for every species. The impact of heavy metals (Hg, Cd, Cu, Pb) in the form of chloride salts on the growth...

  19. Biodiesel Production From Algae to Overcome the Energy Crisis

    Directory of Open Access Journals (Sweden)

    Suliman Khan

    2017-10-01

    Full Text Available The use of energy sources has reached at the level that whole world is relying on it. Being the major source of energy, fuels are considered the most important. The fear of diminishing the available sources thirst towards biofuel production has increased during last decades. Considering the food problems, algae gain the most attention to be used as biofuel producers. The use of crop and food-producing plants will never be a best fit into the priorities for biofuel production as they will disturb the food needs. Different types of algae having the different production abilities. Normally algae have 20%–80% oil contents that could be converted into different types of fuels such as kerosene oil and biodiesel. The diesel production from algae is economical and easy. Different species such as tribonema, ulothrix and euglena have good potential for biodiesel production. Gene technology can be used to enhance the production of oil and biodiesel contents and stability of algae. By increasing the genetic expressions, we can find the ways to achieve the required biofuel amounts easily and continuously to overcome the fuels deficiency. The present review article focusses on the role of algae as a possible substitute for fossil fuel as an ideal biofuel reactant.

  20. Algae as a Biofuel: Renewable Source for Liquid Fuel

    Directory of Open Access Journals (Sweden)

    Vijay Kant Pandey

    2016-09-01

    Full Text Available Biofuels produced by algae may provide a feasible alternative to fossil fuels like petroleum sourced fuels. However, looking to limited fossil fuel associated with problems, intensive efforts have been given to search for alternative biofuels like biodiesel. Algae are ubiquitous on earth, have potential to produce biofuel. However, technology of biofuel from algae facing a number of hurdles before it can compete in the fuel market and be broadly organized. Different challenges include strain identification and improvement of algal biomass, both in terms of biofuel productivity and the production of other products to improve the economics of the entire system. Algal biofuels could be made more cost effective by extracting other valuable products from algae and algal strains. Algal oil can be prepared by culture of algae on municipal and industrial wastewaters. Photobioreactors methods provide a controlled environment that can be tailored to the specific demands of high production of algae to attain a consistently good yield of biofuel. The algal biomass has been reported to yield high oil contents and have good amount of the biodiesel production capacity. In this article, it has been attempted to review to elucidate the approaches for making algal biodiesel economically competitive with respect to petrodiesel. Consequently, R & D work has been carried out for the growth, harvesting, oil extraction and conversion to biodiesel from algal sources.

  1. Radionuclides and trace metals in eastern Mediterranean Sea algae

    Energy Technology Data Exchange (ETDEWEB)

    Al-Masri, M.S. E-mail: msmasri@aec.org.sy; Mamish, S.; Budier, Y

    2003-07-01

    Three types of sea alga distributed along the Syrian coast have been collected and analyzed for radioactivity and trace elements. Results have shown that {sup 137}Cs concentrations in all the analyzed sample were relatively low (less than 1.2 Bq kg{sup -1} dry weight) while the levels of naturally occurring radionuclides, such as {sup 210}Po and {sup 210}Pb, were found to be high in most samples; the highest observed value (27.43 Bq kg{sup -1} dry weight) for {sup 210}Po being in the red Jania longifurca alga. In addition, most brown alga species were also found to accumulate {sup 210}Po, which indicates their selectivity to this isotope. On the other hand, brown alga (Cystoseira and Sargassum Vulgare) have shown a clear selectivity for some trace metals such as Cr, As, Cu and Co, this selectivity may encourage their use as biomonitor for pollution by trace metals. Moreover, the red alga species were found to contain the highest levels of Mg while the brown alga species were found to concentrate Fe, Mn, Na and K and nonmetals such as Cl, I and Br.

  2. Development of Green Fuels From Algae - The University of Tulsa

    Energy Technology Data Exchange (ETDEWEB)

    Crunkleton, Daniel; Price, Geoffrey; Johannes, Tyler; Cremaschi, Selen

    2012-12-03

    The general public has become increasingly aware of the pitfalls encountered with the continued reliance on fossil fuels in the industrialized world. In response, the scientific community is in the process of developing non-fossil fuel technologies that can supply adequate energy while also being environmentally friendly. In this project, we concentrate on green fuels which we define as those capable of being produced from renewable and sustainable resources in a way that is compatible with the current transportation fuel infrastructure. One route to green fuels that has received relatively little attention begins with algae as a feedstock. Algae are a diverse group of aquatic, photosynthetic organisms, generally categorized as either macroalgae (i.e. seaweed) or microalgae. Microalgae constitute a spectacularly diverse group of prokaryotic and eukaryotic unicellular organisms and account for approximately 50% of global organic carbon fixation. The PI's have subdivided the proposed research program into three main research areas, all of which are essential to the development of commercially viable algae fuels compatible with current energy infrastructure. In the fuel development focus, catalytic cracking reactions of algae oils is optimized. In the species development project, genetic engineering is used to create microalgae strains that are capable of high-level hydrocarbon production. For the modeling effort, the construction of multi-scaled models of algae production was prioritized, including integrating small-scale hydrodynamic models of algae production and reactor design and large-scale design optimization models.

  3. Micro-algae: French players discuss the matter

    International Nuclear Information System (INIS)

    Bouveret, T.

    2013-01-01

    About 75000 species of algae have been reported so far, the domains of application are huge and investment are increasing all around the world. One of the difficulties is to find the most appropriate algae to a specific application. Some development programs have failed scientifically or economically for instance the production of protein for animal food from the chlorella algae or the production of bio-fuel from C14-C18 chains, from zeaxanthine and from phycoerytrine. On the other side some research programs have led to promising industrial applications such as the production of food for fish and farm animals. Some research fields are completely innovative such as the use of micro-algae for the construction of bio-walls for buildings. Micro-algae are diverse and fragile. Photo-bioreactors have been designed to breed fragile algae like some types of chlorophycees used in bio-fuel and in cosmetics, a prototype has been tested for 15 months and its production is about 2 kg of dry matter a day. (A.C.)

  4. Biofuels and algae; Biocarburants, la promesse des algues

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-07-15

    Bio-fuels based on micro-algae are promising, their licensing for being used in plane fuels in a mix containing 50% of fossil kerosene is expected in the coming months. In United-States research on bio-fuels has been made more important since 2006 when 2 policies were launched: 'Advanced energy initiative' and 'Twenty-in-ten', the latter aiming to develop alternative fuels. In Europe less investment has been made concerning micro-algae fuels but research programs were launched in Spain, United-Kingdom and France. In France 3 important projects were launched: SHAMASH (2006-2010) whose aim is to produce lipidic fuels from micro-algae, ALGOHUB (2008-2013) whose aim is to use micro-algae as a raw material for humane and animal food, medicine and cosmetics, SYMBIOSE (2009-2011) whose aim is the optimization of the production of methane through the anaerobic digestion of micro-algae, SALINALGUE (2010-2016) whose aim is to grow micro-algae for the production of bio-energies and bio-products. (A.C.)

  5. Radionuclides and trace metals in eastern Mediterranean Sea algae

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Mamish, S.; Budier, Y.

    2003-01-01

    Three types of sea alga distributed along the Syrian coast have been collected and analyzed for radioactivity and trace elements. Results have shown that 137 Cs concentrations in all the analyzed sample were relatively low (less than 1.2 Bq kg -1 dry weight) while the levels of naturally occurring radionuclides, such as 210 Po and 210 Pb, were found to be high in most samples; the highest observed value (27.43 Bq kg -1 dry weight) for 210 Po being in the red Jania longifurca alga. In addition, most brown alga species were also found to accumulate 210 Po, which indicates their selectivity to this isotope. On the other hand, brown alga (Cystoseira and Sargassum Vulgare) have shown a clear selectivity for some trace metals such as Cr, As, Cu and Co, this selectivity may encourage their use as biomonitor for pollution by trace metals. Moreover, the red alga species were found to contain the highest levels of Mg while the brown alga species were found to concentrate Fe, Mn, Na and K and nonmetals such as Cl, I and Br

  6. Photoprotection strategies of the alga Nannochloropsis gaditana.

    Science.gov (United States)

    Chukhutsina, Volha U; Fristedt, Rikard; Morosinotto, Tomas; Croce, Roberta

    2017-07-01

    Nannochloropsis spp. are algae with high potential for biotechnological applications due to their capacity to accumulate lipids. However, little is known about their photosynthetic apparatus and acclimation/photoprotective strategies. In this work, we studied the mechanisms of non-photochemical quenching (NPQ), the fast response to high light stress, in Nannochloropsis gaditana by "locking" the cells in six different states during quenching activation and relaxation. Combining biochemical analysis with time-resolved fluorescence spectroscopy, we correlated each NPQ state with the presence of two well-known NPQ components: de-epoxidized xanthophylls and stress-related antenna proteins (LHCXs). We demonstrated that after exposure to strong light, the rapid quenching that takes place in the antennas of both photosystems was associated with the presence of LHCXs. At later stages, quenching occurs mainly in the antennas of PSII and correlates with the amount of de-epoxidised xanthophylls. We also observed changes in the distribution of excitation energy between photosystems, which suggests redistribution of excitation between photosystems as part of the photo-protective strategy. A multistep model for NPQ induction and relaxation in N. gaditana is discussed. Copyright © 2017. Published by Elsevier B.V.

  7. Coccolithophorid algae culture in closed photobioreactors.

    Science.gov (United States)

    Moheimani, Navid R; Isdepsky, Andreas; Lisec, Jan; Raes, Eric; Borowitzka, Michael A

    2011-09-01

    The feasibility of growth, calcium carbonate and lipid production of the coccolithophorid algae (Prymnesiophyceae), Pleurochrysis carterae, Emiliania huxleyi, and Gephyrocapsa oceanica, was investigated in plate, carboy, airlift, and tubular photobioreactors. The plate photobioreactor was the most promising closed cultivation system. All species could be grown in the carboy photobioreactor. However, P. carterae was the only species which grew in an airlift photobioreactor. Despite several attempts to grow these coccolithophorid species in the tubular photobioreactor (Biocoil), including modification of the airlift and sparger design, no net growth could be achieved. The shear produced by turbulence and bubble effects are the most likely reasons for this failure to grow in the Biocoil. The highest total dry weight, lipid and calcium carbonate productivities achieved by P. carterae in the plate photobioreactors were 0.54, 0.12, and 0.06 g L(-1) day(-1) respectively. Irrespective of the type of photobioreactor, the productivities were P. carterae > E. huxleyi > G. oceanica. Pleurochrysis carterae lipid (20-25% of dry weight) and calcium carbonate (11-12% of dry weight) contents were also the highest of all species tested. Copyright © 2011 Wiley Periodicals, Inc.

  8. Is the Future Really in Algae?

    Science.gov (United States)

    Trent, Jonathan

    2011-01-01

    Having just emerged from the warmest decade on record and watching as the oceans acidify, global resources peak, the world's population continues to climb, and nearly half of all known species face extinction by the end of the century. We stand on the threshold of one of the most important transition in human history-the transition from hunting-and-gathering our energy to cultivating sustainable, carbon-neutral, environmentally-friendly energy supplies. Can we "cultivate" enerm without competing with agriculture for land, freshwater, or fertilizer? Can we develop an "ecology of technology" that optimizes our use of limited resources? Is human activity compatible with improved conditions in the world's oceans? Will our ingenuity prevail in time to make a difference for our children and the children of all species? With support from NASA ARMD and the California Energy Commission, a group of dedicated scientists and engineers are working on a project called OMEGA (Offshore Membrane Enclosures for Growing Algae), to provide practical answers to these critical questions and to leave a legacy of hope for the oceans and for the future.

  9. Detection of Cyanotoxins in Algae Dietary Supplements

    Directory of Open Access Journals (Sweden)

    Audrey Roy-Lachapelle

    2017-02-01

    Full Text Available Algae dietary supplements are marketed worldwide as natural health products. Although their proprieties have been claimed as beneficial to improve overall health, there have been several previous reports of contamination by cyanotoxins. These products generally contain non-toxic cyanobacteria, but the methods of cultivation in natural waters without appropriate quality controls allow contamination by toxin producer species present in the natural environment. In this study, we investigated the presence of total microcystins, seven individual microcystins (RR, YR, LR, LA, LY, LW, LF, anatoxin-a, dihydroanatoxin-a, epoxyanatoxin-a, cylindrospermopsin, saxitoxin, and β-methylamino-l-alanine in 18 different commercially available products containing Spirulina or Aphanizomenon flos-aquae. Total microcystins analysis was accomplished using a Lemieux oxidation and a chemical derivatization using dansyl chloride was needed for the simultaneous analysis of cylindrospermopsin, saxitoxin, and β-methylamino-l-alanine. Moreover, the use of laser diode thermal desorption (LDTD and ultra-high performance liquid chromatography (UHPLC both coupled to high resolution mass spectrometry (HRMS enabled high performance detection and quantitation. Out of the 18 products analyzed, 8 contained some cyanotoxins at levels exceeding the tolerable daily intake values. The presence of cyanotoxins in these algal dietary supplements reinforces the need for a better quality control as well as consumer’s awareness on the potential risks associated with the consumption of these supplements.

  10. Lipid oxidation in base algae oil and water-in-algae oil emulsion: Impact of natural antioxidants and emulsifiers.

    Science.gov (United States)

    Chen, Bingcan; Rao, Jiajia; Ding, Yangping; McClements, David Julian; Decker, Eric Andrew

    2016-07-01

    The impact of natural hydrophilic antioxidants, metal chelators, and hydrophilic antioxidant/metal chelator mixture on the oxidative stability of base algae oil and water-in-algae oil emulsion was investigated. The results showed that green tea extract and ascorbic acid had greatest protective effect against algae oil oxidation and generated four day lag phase, whereas rosmarinic acid, grape seed extract, grape seed extract polymer, deferoxamine (DFO), and ethylenediaminetetraacetic acid (EDTA) had no significant protective effect. Besides, there was no synergistic effect observed between natural antioxidants and ascorbic acid. The emulsifiers are critical to the physicochemical stability of water-in-algae oil emulsions. Polyglycerol polyricinoleate (PGPR) promoted the oxidation of emulsion. Conversely, the protective effect on algae oil oxidation was appreciated when defatted soybean lecithin (PC 75) or defatted lyso-lecithin (Lyso-PC) was added. The role of hydrophilic antioxidants in emulsion was similar to that in algae oil except EDTA which demonstrated strong antioxidative effect in emulsion. The results could provide information to build up stable food products containing polyunsaturated fatty acids (PUFA). Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. SOIL ALGAE OF BLADE OF COIL IN DONETSK REGION

    Directory of Open Access Journals (Sweden)

    Maltseva I.A.

    2011-12-01

    Full Text Available On territory of Donbass for more than 200 years the underground coal mining has produced, accompanied by the formation of the mine dumps. Finding ways to reduce their negative impact on the environment should be based on their comprehensive study. The soil algae are active participants in the syngenetic processes in industrial dumps of different origin. The purpose of this paper is to identify the species composition and dominant algae groups in dump mine SH/U5 “Western” in the western part of Donetsk.The test blade is covered with vegetation to the middle from all sides, and on the north side of 20-25 m to the top. The vegetation cover of the lower and middle tiers of all the exposures range in 70-80%. Projective vegetation cover of upper tiers of the northern, north-eastern and north-western exposures are in the range of 20-40%, other – 5-10%. We revealed some 38 algae species as a result of our research in southern, northern, western, and eastern slopes of the blade “Western”. The highest species diversity has Chlorophyta - 14 species (36.8% of the total number of species, then Cyanophyta - 9 (23,7%, Bacillariophyta - 7 (18,4%, Xantophyta - 5 (13.2%, and Eustigmatophyta - 3 (7.9%. The dominants are represented by Hantzschia amphyoxys (Ehrenberg Grunow in Cleve et Grunow, Bracteacoccus aerius, Klebsormidium flaccidum (Kützing Silva et al., Phormidium autumnale, Pinnularia borealis Ehrenberg, Planothidium lanceolatum (Brebisson in Kützing Bukhtiyarova, Xanthonema exile (Klebs Silva.It should be noted that the species composition of algae groups in different slopes of the blade was significantly different. Jacquard coefficient was calculated for algae communities varied in the range of 15,4-39,1%. The smallest number of algae species was observed on the southern slope of the blade (14 species, maximum was registered in the areas of north and west slopes. Differences in the species composition of algae were also observed in three

  12. Two-Step Evolution of Endosymbiosis between Hydra and Algae

    KAUST Repository

    Ishikawa, Masakazu

    2016-07-09

    In the Hydra vulgaris group, only 2 of the 25 strains in the collection of the National Institute of Genetics in Japan currently show endosymbiosis with green algae. However, whether the other non-symbiotic strains also have the potential to harbor algae remains unknown. The endosymbiotic potential of non-symbiotic strains that can harbor algae may have been acquired before or during divergence of the strains. With the aim of understanding the evolutionary process of endosymbiosis in the H. vulgaris group, we examined the endosymbiotic potential of non-symbiotic strains of the H. vulgaris group by artificially introducing endosymbiotic algae. We found that 12 of the 23 non-symbiotic strains were able to harbor the algae until reaching the grand-offspring through the asexual reproduction by budding. Moreover, a phylogenetic analysis of mitochondrial genome sequences showed that all the strains with endosymbiotic potential grouped into a single cluster (cluster γ). This cluster contained two strains (J7 and J10) that currently harbor algae; however, these strains were not the closest relatives. These results suggest that evolution of endosymbiosis occurred in two steps; first, endosymbiotic potential was gained once in the ancestor of the cluster γ lineage; second, strains J7 and J10 obtained algae independently after the divergence of the strains. By demonstrating the evolution of the endosymbiotic potential in non-symbiotic H. vulgaris group strains, we have clearly distinguished two evolutionary steps. The step-by-step evolutionary process provides significant insight into the evolution of endosymbiosis in cnidarians.

  13. [Toxicity of Coptis chinensis Rhizome Extracts to Green Algae].

    Science.gov (United States)

    Chen, Ya-nan; Yuan, Ling

    2015-05-01

    Coptis chinensis contains antiseptic alkaloids and thus its rhizomes and preparations are widely used for the treatment of.fish diseases. In order to realize the risk of water ecosystems produced by this medical herb and preparations used in aquaculture, the present experiment was carried out to study the toxicity of Coptis chinensis rhizome extract (CRE) to Scenedesmus oblique and Chlorella pyrenoidosa grown in culture solution with 0.00 (CK), 0.088 (Tl), 0.44 (T2) and 1.76 mg · L(-1) (T3) of CRE, respectively. The results show that low concentration of CRE (T1) inhibited the growth rate of the alga and high CRE (T2 and T3) ceased growth and reproductions. CRE also decreased the chlorophyll and proteins in alga cells, indicating the inhibition of photosynthesis and protein biosynthesis, which could be direct reasons for the low growth rate and death of green alga. The efflux of protons and substances from alga cells led to pH reduction and conductivity increment in culture solution with CRE. Furthermore, the activity of superoxide dismutase in alga increased at the beginning of CRE in T1 and T2 treatments but decreased as time prolonged which was in contrast to high CRE treatment. And the long exposure to low CRE treatment behaved otherwise. This suggests that the low concentration of CRE could induce the resistant reactions in alga at initial time but high CRE concentration or long exposure even at low CRE concentration could inhibit the enzyme synthesis. Similarly, malondialdehyde in alga increased as CRE concentrations increased in culture solutions, implying the damage and high permeability of cell membrane. In general, Chlorella pyrenoidosa was more sensitive to CRE. The abuse of rhizomes and preparations in aquaculture and intensive cultivation of Coptis chinensis plants in a large scale might produce ecological risks to primary productivity of water ecosystems.

  14. Two-step evolution of endosymbiosis between hydra and algae.

    Science.gov (United States)

    Ishikawa, Masakazu; Shimizu, Hiroshi; Nozawa, Masafumi; Ikeo, Kazuho; Gojobori, Takashi

    2016-10-01

    In the Hydra vulgaris group, only 2 of the 25 strains in the collection of the National Institute of Genetics in Japan currently show endosymbiosis with green algae. However, whether the other non-symbiotic strains also have the potential to harbor algae remains unknown. The endosymbiotic potential of non-symbiotic strains that can harbor algae may have been acquired before or during divergence of the strains. With the aim of understanding the evolutionary process of endosymbiosis in the H. vulgaris group, we examined the endosymbiotic potential of non-symbiotic strains of the H. vulgaris group by artificially introducing endosymbiotic algae. We found that 12 of the 23 non-symbiotic strains were able to harbor the algae until reaching the grand-offspring through the asexual reproduction by budding. Moreover, a phylogenetic analysis of mitochondrial genome sequences showed that all the strains with endosymbiotic potential grouped into a single cluster (cluster γ). This cluster contained two strains (J7 and J10) that currently harbor algae; however, these strains were not the closest relatives. These results suggest that evolution of endosymbiosis occurred in two steps; first, endosymbiotic potential was gained once in the ancestor of the cluster γ lineage; second, strains J7 and J10 obtained algae independently after the divergence of the strains. By demonstrating the evolution of the endosymbiotic potential in non-symbiotic H. vulgaris group strains, we have clearly distinguished two evolutionary steps. The step-by-step evolutionary process provides significant insight into the evolution of endosymbiosis in cnidarians. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Optimal control of algae growth by controlling CO 2 and nutrition flow using Pontryagin Maximum Principle

    Science.gov (United States)

    Mardlijah; Jamil, Ahmad; Hanafi, Lukman; Sanjaya, Suharmadi

    2017-09-01

    There are so many benefit of algae. One of them is using for renewable energy and sustainable in the future. The greater growth of algae will increasing biodiesel production and the increase of algae growth is influenced by glucose, nutrients and photosynthesis process. In this paper, the optimal control problem of the growth of algae is discussed. The objective function is to maximize the concentration of dry algae while the control is the flow of carbon dioxide and the nutrition. The solution is obtained by applying the Pontryagin Maximum Principle. and the result show that the concentration of algae increased more than 15 %.

  16. Method and apparatus using an active ionic liquid for algae biofuel harvest and extraction

    Science.gov (United States)

    Salvo, Roberto Di; Reich, Alton; Dykes, Jr., H. Waite H.; Teixeira, Rodrigo

    2012-11-06

    The invention relates to use of an active ionic liquid to dissolve algae cell walls. The ionic liquid is used to, in an energy efficient manner, dissolve and/or lyse an algae cell walls, which releases algae constituents used in the creation of energy, fuel, and/or cosmetic components. The ionic liquids include ionic salts having multiple charge centers, low, very low, and ultra low melting point ionic liquids, and combinations of ionic liquids. An algae treatment system is described, which processes wet algae in a lysing reactor, separates out algae constituent products, and optionally recovers the ionic liquid in an energy efficient manner.

  17. Algae-bacteria interactions: Evolution, ecology and emerging applications.

    Science.gov (United States)

    Ramanan, Rishiram; Kim, Byung-Hyuk; Cho, Dae-Hyun; Oh, Hee-Mock; Kim, Hee-Sik

    2016-01-01

    Algae and bacteria have coexisted ever since the early stages of evolution. This coevolution has revolutionized life on earth in many aspects. Algae and bacteria together influence ecosystems as varied as deep seas to lichens and represent all conceivable modes of interactions - from mutualism to parasitism. Several studies have shown that algae and bacteria synergistically affect each other's physiology and metabolism, a classic case being algae-roseobacter interaction. These interactions are ubiquitous and define the primary productivity in most ecosystems. In recent years, algae have received much attention for industrial exploitation but their interaction with bacteria is often considered a contamination during commercialization. A few recent studies have shown that bacteria not only enhance algal growth but also help in flocculation, both essential processes in algal biotechnology. Hence, there is a need to understand these interactions from an evolutionary and ecological standpoint, and integrate this understanding for industrial use. Here we reflect on the diversity of such relationships and their associated mechanisms, as well as the habitats that they mutually influence. This review also outlines the role of these interactions in key evolutionary events such as endosymbiosis, besides their ecological role in biogeochemical cycles. Finally, we focus on extending such studies on algal-bacterial interactions to various environmental and bio-technological applications. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Overcoming Microalgae Harvesting Barrier by Activated Algae Granules.

    Science.gov (United States)

    Tiron, Olga; Bumbac, Costel; Manea, Elena; Stefanescu, Mihai; Nita Lazar, Mihai

    2017-07-05

    The economic factor of the microalgae harvesting step acts as a barrier to scaling up microalgae-based technology designed for wastewater treatment. In view of that, this study presents an alternative microalgae-bacteria system, which is proposed for eliminating the economic obstacle. Instead of the microalgae-bacteria (activated algae) flocs, the study aimed to develop activated algae granules comprising the microalgae Chlorella sp. as a target species. The presence of the filamentous microalgae (Phormidium sp.) was necessary for the occurrence of the granulation processes. A progressive decrease in frequency of the free Chlorella sp. cells was achieved once with the development of the activated algae granules as a result of the target microalgae being captured in the dense and tangled network of filaments. The mature activated algae granules ranged between 600 and 2,000 µm, and were characterized by a compact structure and significant settling ability (21.6 ± 0.9 m/h). In relation to the main aim of this study, a microalgae recovery efficiency of higher than 99% was achieved only by fast sedimentation of the granules; this performance highlighted the viability of the granular activated algae system for sustaining a microalgae harvesting procedure with neither cost nor energy inputs.

  19. Development and characteristics of an adhesion bioassay for ectocarpoid algae.

    Science.gov (United States)

    Evariste, Emmanuelle; Gachon, Claire M M; Callow, Maureen E; Callow, James A

    2012-01-01

    Species of filamentous brown algae in the family Ectocarpaceae are significant members of fouling communities. However, there are few systematic studies on the influence of surface physico-chemical properties on their adhesion. In the present paper the development of a novel, laboratory-based adhesion bioassay for ectocarpoid algae, at an appropriate scale for the screening of sets of experimental samples in well-replicated and controlled experiments is described. The assays are based on the colonization of surfaces from a starting inoculum consisting of multicellular filaments obtained by blending the cultured alga Ectocarpus crouaniorum. The adhesion strength of the biomass after 14 days growth was assessed by applying a hydrodynamic shear stress. Results from adhesion tests on a set of standard surfaces showed that E. crouaniorum adhered more weakly to the amphiphilic Intersleek® 900 than to the more hydrophobic Intersleek® 700 and Silastic® T2 coatings. Adhesion to hydrophilic glass was also weak. Similar results were obtained for other cultivated species of Ectocarpus but differed from those obtained with the related ectocarpoid species Hincksia secunda. The response of the ectocarpoid algae to the surfaces was also compared to that for the green alga, Ulva.

  20. Algae Production from Wastewater Resources: An Engineering and Cost Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schoenung, Susan [Longitude 122 West, Inc.; Efroymson, Rebecca Ann [ORNL

    2018-03-01

    Co-locating algae cultivation ponds near municipal wastewater (MWW) facilities provides the opportunity to make use of the nitrogen and phosphorus compounds in the wastewater as nutrient sources for the algae. This use benefits MWW facilities, the algae biomass and biofuel or bioproduct industry, and the users of streams where treated or untreated waste would be discharged. Nutrient compounds can lead to eutrophication, hypoxia, and adverse effects to some organisms if released downstream. This analysis presents an estimate of the cost savings made possible to cultivation facilities by using the nutrients from wastewater for algae growth rather than purchase of the nutrients. The analysis takes into consideration the cost of pipe transport from the wastewater facility to the algae ponds, a cost factor that has not been publicly documented in the past. The results show that the savings in nutrient costs can support a wastewater transport distance up to 10 miles for a 1000-acre-pond facility, with potential adjustments for different operating assumptions.

  1. Anti-phytopathogenic activities of macro-algae extracts.

    Science.gov (United States)

    Jiménez, Edra; Dorta, Fernando; Medina, Cristian; Ramírez, Alberto; Ramírez, Ingrid; Peña-Cortés, Hugo

    2011-01-01

    Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

  2. Boron uptake, localization, and speciation in marine brown algae.

    Science.gov (United States)

    Miller, Eric P; Wu, Youxian; Carrano, Carl J

    2016-02-01

    In contrast to the generally boron-poor terrestrial environment, the concentration of boron in the marine environment is relatively high (0.4 mM) and while there has been extensive interest in its use as a surrogate of pH in paleoclimate studies in the context of climate change-related questions, the relatively depth independent, and the generally non-nutrient-like concentration profile of this element have led to boron being neglected as a potentially biologically relevant element in the ocean. Among the marine plant-like organisms the brown algae (Phaeophyta) are one of only five lineages of photosynthetic eukaryotes to have evolved complex multicellularity. Many of unusual and often unique features of brown algae are attributable to this singular evolutionary history. These adaptations are a reflection of the marine coastal environment which brown algae dominate in terms of biomass. Consequently, brown algae are of fundamental importance to oceanic ecology, geochemistry, and coastal industry. Our results indicate that boron is taken up by a facilitated diffusion mechanism against a considerable concentration gradient. Furthermore, in both Ectocarpus and Macrocystis some boron is most likely bound to cell wall constituent alginate and the photoassimilate mannitol located in sieve cells. Herein, we describe boron uptake, speciation, localization and possible biological function in two species of brown algae, Macrocystis pyrifera and Ectocarpus siliculosus.

  3. Anti-Phytopathogenic Activities of Macro-Algae Extracts

    Directory of Open Access Journals (Sweden)

    Ingrid Ramírez

    2011-05-01

    Full Text Available Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

  4. Evolution of reproductive development in the volvocine algae.

    Science.gov (United States)

    Hallmann, Armin

    2011-06-01

    The evolution of multicellularity, the separation of germline cells from sterile somatic cells, and the generation of a male-female dichotomy are certainly among the greatest innovations of eukaryotes. Remarkably, phylogenetic analysis suggests that the shift from simple to complex, differentiated multicellularity was not a unique progression in the evolution of life, but in fact a quite frequent event. The spheroidal green alga Volvox and its close relatives, the volvocine algae, span the full range of organizational complexity, from unicellular and colonial genera to multicellular genera with a full germ-soma division of labor and male-female dichotomy; thus, these algae are ideal model organisms for addressing fundamental issues related to the transition to multicellularity and for discovering universal rules that characterize this transition. Of all living species, Volvox carteri represents the simplest version of an immortal germline producing specialized somatic cells. This cellular specialization involved the emergence of mortality and the production of the first dead ancestors in the evolution of this lineage. Volvocine algae therefore exemplify the evolution of cellular cooperation from cellular autonomy. They also serve as a prime example of the evolution of complex traits by a few successive, small steps. Thus, we learn from volvocine algae that the evolutionary transition to complex, multicellular life is probably much easier to achieve than is commonly believed. © The Author(s) 2010. This article is published with open access at Springerlink.com

  5. Radionuclides in macro algae at Monaco following the Chernobyl accident

    International Nuclear Information System (INIS)

    Holm, E.; Ballestra, S.; Lopez, J.J.; Bulos, A.; Whitehead, N.E.; Barci-Funel, G.; Ardisson, G.

    1994-01-01

    Samples of macro algae, Codmium tomentosum (green), Corallina mediterranea (red), Sphaerococcus coronopifolius (red) and Dictyota dichotoma (brown), were collected off Monaco during 1984 and 1988 and analysed for gamma-emitting radionuclides and transuranium elements. Due to the Chernobyl accident, increased radioactivity in the atmosphere at Monaco was recorded on 30 April 1986 with maximal activity concentrations on 2-3 May. The maximal activity concentrations in sea water occurred on 5-6 May and in the algae on 11 May. The decrease of activity concentrations can be described after May 11 as a single exponential relationship, where elimination rates for different radionuclides and different species specific to the environment can be calculated. The elimination rates thus observed correspond to mean residence times between 70 and 370 days corrected for physical decay. The concentration factors were also estimated and the highest values were found for 131 I, 129 Te m , and 110 Ag m and lowest for radiocesium and 140 Ba. The red algae Sphaerococcus coronopifoius showed generally higher concentration factors than green and brown algae. Regarding transuranium elements, a theoretical contribution from the Chernobyl accident can be made but only 242 Cm was detected in the algae above previous levels before the accident, due to the relatively small fallout of transuranics. (author) 23 refs.; 9 figs.; 4 tabs

  6. Acute toxicity and associated mechanisms of four strobilurins in algae.

    Science.gov (United States)

    Liu, Xiaoxu; Wang, Yu; Chen, Hao; Zhang, Junli; Wang, Chengju; Li, Xuefeng; Pang, Sen

    2018-04-03

    Strobilurins have been reported highly toxic to non-target aquatic organisms but few illustrated how they cause toxic effects on algae. This study investigated the acute toxicity of Kresoxim-methy (KRE), Pyraclostrobin (PYR), Trifloxystrobin (TRI) and Picoxystrobin (PIC) on two algae and their toxicity mechanisms. Four strobilurins showed lower toxic effects on Chlorella pyrenoidsa but higher on Chlorella vulgaris. bc1 complex activities in C. vulgaris were significantly inhibited by all strobilurins, suggesting bc 1 complex might be the target of strobilurin toxicity in algae. Moreover, SOD, CAT and POD activities were significantly up-regulated by all doses of KRE, PYR and PIC. In contrast, low concentrations of TRI stimulated SOD and POD activities but highest concentration significantly inhibited those activities. Comet assays showed damaged DNA in C. vulgaris by four strobulirins, suggesting their potential genotoxic threats to algae. The results illustrated acute toxicity by strobulirins on algae and their possible toxicity mechanisms. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Sustainability of algae derived biodiesel: a mass balance approach.

    Science.gov (United States)

    Pfromm, Peter H; Amanor-Boadu, Vincent; Nelson, Richard

    2011-01-01

    A rigorous chemical engineering mass balance/unit operations approach is applied here to bio-diesel from algae mass culture. An equivalent of 50,000,000 gallons per year (0.006002 m3/s) of petroleum-based Number 2 fuel oil (US, diesel for compression-ignition engines, about 0.1% of annual US consumption) from oleaginous algae is the target. Methyl algaeate and ethyl algaeate diesel can according to this analysis conceptually be produced largely in a technologically sustainable way albeit at a lower available diesel yield. About 11 square miles of algae ponds would be needed with optimistic assumptions of 50 g biomass yield per day and m2 pond area. CO2 to foster algae growth should be supplied from a sustainable source such as a biomass-based ethanol production. Reliance on fossil-based CO2 from power plants or fertilizer production renders algae diesel non-sustainable in the long term. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Visualization of oxygen distribution patterns caused by coral and algae.

    Science.gov (United States)

    Haas, Andreas F; Gregg, Allison K; Smith, Jennifer E; Abieri, Maria L; Hatay, Mark; Rohwer, Forest

    2013-01-01

    Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp.) and a hermatypic coral (Favia sp.) separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were assessed in light and dark conditions and under varying flow regimes. The images show discrete high oxygen concentration regions above the organisms during lighted periods and low oxygen in the dark. Size and orientation of these areas were dependent on flow regime. For corals and algae in close proximity the 2D optodes show areas of extremely low oxygen concentration at the interaction interfaces under both dark (18.4 ± 7.7 µmol O2 L(- 1)) and daylight (97.9 ± 27.5 µmol O2 L(- 1)) conditions. These images present the first two-dimensional visualization of oxygen gradients generated by benthic reef algae and corals under varying flow conditions and provide a 2D depiction of previously observed hypoxic zones at coral algae interfaces. This approach allows for visualization of locally confined, distinctive alterations of oxygen concentrations facilitated by benthic organisms and provides compelling evidence for hypoxic conditions at coral-algae interaction zones.

  9. Visualization of oxygen distribution patterns caused by coral and algae

    Directory of Open Access Journals (Sweden)

    Andreas F. Haas

    2013-07-01

    Full Text Available Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp. and a hermatypic coral (Favia sp. separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were assessed in light and dark conditions and under varying flow regimes. The images show discrete high oxygen concentration regions above the organisms during lighted periods and low oxygen in the dark. Size and orientation of these areas were dependent on flow regime. For corals and algae in close proximity the 2D optodes show areas of extremely low oxygen concentration at the interaction interfaces under both dark (18.4 ± 7.7 µmol O2 L- 1 and daylight (97.9 ± 27.5 µmol O2 L- 1 conditions. These images present the first two-dimensional visualization of oxygen gradients generated by benthic reef algae and corals under varying flow conditions and provide a 2D depiction of previously observed hypoxic zones at coral algae interfaces. This approach allows for visualization of locally confined, distinctive alterations of oxygen concentrations facilitated by benthic organisms and provides compelling evidence for hypoxic conditions at coral-algae interaction zones.

  10. Algae from the arid southwestern United States: an annotated bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, W.H.; Gaines, S.R.

    1983-06-01

    Desert algae are attractive biomass producers for capturing solar energy through photosynthesis of organic matter. They are probably capable of higher yields and efficiencies of light utilization than higher plants, and are already adapted to extremes of sunlight intensity, salinity and temperature such as are found in the desert. This report consists of an annotated bibliography of the literature on algae from the arid southwestern United States. It was prepared in anticipation of efforts to isolate desert algae and study their yields in the laboratory. These steps are necessary prior to setting up outdoor algal culture ponds. Desert areas are attractive for such applications because land, sunlight, and, to some extent, water resources are abundant there. References are sorted by state.

  11. Effects of Harmful Algae on the Physiology of Fishes

    DEFF Research Database (Denmark)

    Svendsen, Morten Bo Søndergaard

    Blooms of harmful planktonic algae causing adverse effects in aquatic environments are a global problem, causing both human morbidity and killing aquatic lifeforms worldwide. Focusing on fish kills, it is largely unknown what mechanisms of the fish’s physiology are affected during exposure......-waters having enough oxygen to sustain life, but not too warm like the surface water layer. The proposed adverse pathway, being gill destruction, for fish exposed to Alexandrium monilatum suggests that co-occurring events of Alexandrium monilatum and oxygen squeeze events will tighten the oxygen limitation...... is largely caused by the fish and to a lesser extent the experimental setup. Before this thesis, systematic studies of fish physiology under the influence of harmful algae consisted of one algae species, Chattonella marina. Now there are a total of 4 species studied. Lastly, during the Ph...

  12. Designer proton-channel transgenic algae for photobiological hydrogen production

    Science.gov (United States)

    Lee, James Weifu [Knoxville, TN

    2011-04-26

    A designer proton-channel transgenic alga for photobiological hydrogen production that is specifically designed for production of molecular hydrogen (H.sub.2) through photosynthetic water splitting. The designer transgenic alga includes proton-conductive channels that are expressed to produce such uncoupler proteins in an amount sufficient to increase the algal H.sub.2 productivity. In one embodiment the designer proton-channel transgene is a nucleic acid construct (300) including a PCR forward primer (302), an externally inducible promoter (304), a transit targeting sequence (306), a designer proton-channel encoding sequence (308), a transcription and translation terminator (310), and a PCR reverse primer (312). In various embodiments, the designer proton-channel transgenic algae are used with a gas-separation system (500) and a gas-products-separation and utilization system (600) for photobiological H.sub.2 production.

  13. Sex pheromone of marine algae; Kaiso no sei pheromone

    Energy Technology Data Exchange (ETDEWEB)

    Kajiwara, T. [Yamaguchi University, Yamaguchi (Japan). Faculty of Agriculture

    1997-10-20

    The marine ecosystem skillfully uses various `odor materials` as chemical signals. In particular, this `odor materials` are indispensable for various organisms with no motor function or poor underdeveloped visual sensation in order to maintain or expand their species. German algae scholars found a male gamete induction active material secreted from a female gamete of primitive brown algae in 1971. Eleven kinds of sex pheromones have been found from brown algae up to the present since 1971. All of these found sex pheromones are hydrophobic `odor materials` composed of hydrocarbons containing 8 or 11 carbon atoms or epoxide (oxirane), and are compounds with singular chemical structures as physiological active material in the hydrosphere. Some sex pheromones govern not only inducement of spermatozoons but also discharge of spermatozoons from an antheridium. The sex pheromone with both functions of discharge and inducement was found from the culture solution of a certain tangle weed. 2 refs., 2 figs.

  14. Characteristics of Red Algae Bioplastics/Latex Blends under Tension

    Directory of Open Access Journals (Sweden)

    M. Nizar Machmud

    2013-10-01

    Full Text Available Cassava, corn, sago and the other food crops have been commonly used as raw materials to produce green plastics. However, plastics produced from such crops cannot be tailored to fit a particular requirement due to their poor water resistance and mechanical properties. Nowadays, researchers are hence looking to get alternative raw materials from the other sustainable resources to produce plastics. Their recent published studies have reported that marine red algae, that has been already widely used as a raw material for producing biofuels, is one of the potential algae crops that can be turned into plastics. In this work, Eucheuma Cottonii, that is one of the red alga crops, was used as raw material to produce plastics by using a filtration technique. Selected latex of Artocarpus altilis and Calostropis gigantea was separately then blended with bioplastics derived from the red algae, to replace use of glycerol as plasticizer. Role of the glycerol and the selected latex on physical and mechanical properties of the red algae bioplastics obtained under a tensile test performed at room temperature are discussed. Tensile strength of some starch-based plastics collected from some recent references is also presented in this paperDoi: 10.12777/ijse.5.2.81-88 [How to cite this article: Machmud, M.N., Fahmi, R.,  Abdullah, R., and Kokarkin, C.  (2013. Characteristics of Red Algae Bioplastics/Latex Blends under Tension. International Journal of Science and Engineering, 5(2,81-88. Doi: 10.12777/ijse.5.2.81-88

  15. Inorganic carbon addition stimulates snow algae primary productivity

    Science.gov (United States)

    Hamilton, T. L.; Havig, J. R.

    2017-12-01

    Earth has experienced glacial/interglacial oscillations throughout its history. Today over 15 million square kilometers (5.8 million square miles) of Earth's land surface is covered in ice including glaciers, ice caps, and the ice sheets of Greenland and Antarctica, most of which are retreating as a consequence of increased atmospheric CO2. Glaciers are teeming with life and supraglacial snow and ice surfaces are often red due to blooms of photoautotrophic algae. Recent evidence suggests the red pigmentation, secondary carotenoids produced in part to thrive under high irradiation, lowers albedo and accelerates melt. However, there are relatively few studies that report the productivity of snow algae communities and the parameters that constrain their growth on snow and ice surfaces. Here, we demonstrate that snow algae primary productivity can be stimulated by the addition of inorganic carbon. We found an increase in light-dependent carbon assimilation in snow algae microcosms amended with increasing amounts of inorganic carbon. Our snow algae communities were dominated by typical cosmopolitan snow algae species recovered from Alpine and Arctic environments. The climate feedbacks necessary to enter and exit glacial/interglacial oscillations are poorly understood. Evidence and models agree that global Snowball events are accompanied by changes in atmospheric CO2 with increasing CO2 necessary for entering periods of interglacial time. Our results demonstrate a positive feedback between increased CO2 and snow algal productivity and presumably growth. With the recent call for bio-albedo effects to be considered in climate models, our results underscore the need for robust climate models to include feedbacks between supraglacial primary productivity, albedo, and atmospheric CO2.

  16. Using the marine unicellular algae in biological monitoring

    Directory of Open Access Journals (Sweden)

    Kapkov V. I.

    2017-06-01

    Full Text Available The possibility of using marine unicellular algae from natural plankton community in biomonitoring of pollution by heavy metals has been investigated. Algae of different taxa from the Mediterranean Sea have been allocated to culture. In the laboratory the culture conditions – i. e. growth medium, temperature, photoperiod, level of artificial light and initial density – have been selected for every species. The impact of heavy metals (Hg, Cd, Cu, Pb in the form of chloride salts on the growth of axenic algae culture has been studied in the modelling experiments. The unicellular marine algae have a very short life cycle, therefore it is possible to use them in the experiments of studying the effect of anthropogenic factors at cellular and population levels on the test-object. With biomonitoring pollution of marine environment by heavy metals and others dangerous toxicants, the major indicators of algae community condition are the cellular cycle and the condition of the photosynthetic apparatus of the cell. The subsequent lysis of cells under the influence of heavy metals leads to the excretion of secondary metabolites which can essentially affect the metal toxicity. The established scales of threshold and lethal concentration of heavy metals for algae of different taxon make it possible to use the ratio of sensitive and resistant species to heavy metals as biological markers when forecasting ecological consequences of pollution of the marine environment by heavy metals. Distinctions in the resistance of different taxon to heavy metals can result in implementing the strategy of selection of test-objects depending on the purposes of the research.

  17. Floating Algae Blooms in the East China Sea

    Science.gov (United States)

    Qi, Lin; Hu, Chuanmin; Wang, Mengqiu; Shang, Shaoling; Wilson, Cara

    2017-11-01

    A floating algae bloom in the East China Sea was observed in Moderate Resolution Imaging Spectroradiometer (MODIS) imagery in May 2017. Using satellite imagery from MODIS, Visible Infrared Imaging Radiometer Suite, Geostationary Ocean Color Imager, and Ocean Land Imager, and combined with numerical particle tracing experiments and laboratory experiments, we examined the history of this bloom as well as similar blooms in previous years and attempted to trace the bloom source and identify the algae type. Results suggest that one bloom origin is offshore Zhejiang coast where algae slicks have appeared in satellite imagery almost every February-March since 2012. Following the Kuroshio Current and Taiwan Warm Current, these "initial" algae slicks are first transported to the northeast to reach South Korea (Jeju Island) and Japan coastal waters (up to 135°E) by early April 2017, and then transported to the northwest to enter the Yellow Sea by the end of April. The transport pathway covers an area known to be rich in Sargassum horneri, and spectral analysis suggests that most of the algae slicks may contain large amount of S. horneri. The bloom covers a water area of 160,000 km2 with pure algae coverage of 530 km2, which exceeds the size of most Ulva blooms that occur every May-July in the Yellow Sea. While blooms of smaller size also occurred in previous years and especially in 2015, the 2017 bloom is hypothesized to be a result of record-high water temperature, increased light availability, and continuous expansion of Porphyra aquaculture along the East China Sea coast.

  18. Homogeneity of Danish environmental and clinical isolates of Shewanella algae

    DEFF Research Database (Denmark)

    Vogel, Birte Fonnesbech; Holt, H.M.; Gerner-Smidt, P.

    2000-01-01

    Danish isolates of Shewanella algae constituted by whole-cell protein profiling a very homogeneous group, and no clear distinction was seen between strains from the marine environment and strains of clinical origin. Although variation between all strains was observed by ribotyping and random...... amplified polymorphic DNA analysis, no clonal relationship between infective strains was found. From several patients, clonally identical strains of S. algae were reisolated up to 8 months after the primary isolation, indicating that the same strain may be able to maintain the infection....

  19. [Effects of aniline and phenol on freshwater algae growth].

    Science.gov (United States)

    Chen, Chuan-ping; Zhang, Ting-ting; He, Mei; Wu, An-ping; Nie, Liu-wang

    2007-01-01

    By the methods of bioassay, this paper studied the effects of aniline or phenol on the growth of Chlorella pyrenoidosa and Scenedesmus obiquus. The results showed that these two compounds had evident effects on the growth of test algae species. For the same species, aniline was more toxic. Under the same concentration of the compounds, S. obiquus was more sensitive than C. pyrenoidosa. These two algae species could degrade or absorb parts of the compounds, and phenol in particular, when their concentrations were lower.

  20. Chemical composition of the green alga Codium Divaricatum Holmes.

    Science.gov (United States)

    He, Zhizhou; Zhang, Anjiang; Ding, Lisheng; Lei, Xinxiang; Sun, Jianzhang; Zhang, Lixue

    2010-12-01

    A new sterol, 24-R-stigmasta-4,25-diene-3β,6β-diol (1), along with three known compounds (2-3), was isolated from the green alga Codium divaricatum Holmes, a traditional Chinese medicine, which is efficacious against cancer. All structures were determined by spectroscopic methods and comparison with related known compounds. Single-crystal X-ray crystallography allowed us to confirm the structure of 1. To our knowledge, the compound 1 is reported as the first from natural source, and compounds 2, 4 have not been isolated from green algae before. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. The attached algae community near Pickering GS: III

    International Nuclear Information System (INIS)

    McKinley, S.R.

    1982-01-01

    The relationship between attached algae and macro-invertebrates in the nearshore zone of Lake Ontario was investigated in the vicinity of the Pickering 'A' NGS. Measures of faunal density, richness, evenness, and biomass were generally higher from areas which supported attached algae. Gammarus fasciatus, Cricotopus bicinctus, Dicrotendipes spp., Orthocladius obumbratus, Cladotanytarsus spp., Orthocladius spp., and Parakiefferiella spp., were significantly correlated with algal standing crop. All of the above dominant invertebrates ingested epiphytes associated with Cladophora glomerata. Attempts to explain the distribution of the zoobenthic assemblages using the physical/biological characteristics of the study area indicated algal cover, substrate size, wind velocity and water temperature were most important

  2. Distribution and biomass estimation of shell-boring algae in the intertidal area at Goa India

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Sharma, S.; Lande, V.

    and particulate organic carbon (POC) values in cultures of the green alga Gomontia sp. and the blue-green alga Plectonema terebrans, in biomass and POC contribution of these two types of microalgae in shells were calculated....

  3. Distribution of algae, seagrasses, and coral communities from Lakshadweep islands, eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Jagtap, T.G.

    Marine algae, seagrasses and coral from the intertidal, lagoon, reef and subtidal regions (up to 22 m depth) at Kavaratti, Agatti, Bangaram and Suheli islands, of Lakshadweep were studied Marine algae and seagrasses were mainly confined...

  4. Value of crops: Quantity, quality and cost price. [algae as a nutritional supplement

    Science.gov (United States)

    Meyer, C.

    1979-01-01

    Possibilities of using algae as a nutritional supplement are examined. The nutritional value and protein content of spirulines of blue algae are discussed. A cost analysis of growing them artificially is presented.

  5. Synthetic algae and cyanobacteria: Great potential but what is the exposure risk?

    Science.gov (United States)

    Green algae and cyanobacteria (hereafter, algae) have the attractive properties of relatively simple genomes, rapid growth rates, and an ability to synthesize useful compounds using solar energy and carbon dioxide. They are attractive targets for applications of synthetic biology...

  6. Calcium signalling in the ciliated protozoan model, Paramecium: strict signal localisation by epigenetically controlled positioning of different Ca²⁺-channels.

    Science.gov (United States)

    Plattner, Helmut

    2015-03-01

    The Paramecium tetraurelia cell is highly organised, with regularly spaced elements pertinent to Ca(2+) signalling under epigenetic control. Vesicles serving as stationary Ca(2+) stores or undergoing trafficking contain Ca(2+)-release channels (PtCRCs) which, according to sequence and domain comparison, are related either to inositol 1,4,5-trisphosphate (InsP3) receptors (IP3R) or to ryanodine receptor-like proteins (RyR-LP) or to both, with intermediate characteristics or deviation from conventional domain structure. Six groups of such PtCRCs have been found. The ryanodine-InsP3-receptor homology (RIH) domain is not always recognisable, in contrast to the channel domain with six trans-membrane domains and the pore between transmembrane domain 5 and 6. Two CRC subtypes tested more closely, PtCRC-II and PtCRC-IV, with and without an InsP3-binding domain, reacted to InsP3 and to caffeine, respectively, and hence represent IP3Rs and RyR-LPs. IP3Rs occur in the contractile vacuole complex where they allow for stochastic constitutive Ca(2+) reflux into the cytosol. RyR-LPs are localised to cortical Ca(2+) stores; they are engaged in dense core-secretory vesicle exocytosis by Ca(2+) release, superimposed by Ca(2+)-influx via non-ciliary Ca(2+)-channels. One or two different types of PtCRCs also occur in other vesicles undergoing trafficking. Since the PtCRCs described combine different features they are considered derivatives of primitive precursors. The highly regular, epigenetically controlled design of a Paramecium cell allows it to make Ca(2+) available very locally, in a most efficient way, along predetermined trafficking pathways, including regulation of exocytosis, endocytosis, phagocytosis and recycling phenomena. The activity of cilia is also regulated by Ca(2+), yet independently from any CRCs, by de- and hyperpolarisation of the cell membrane potential. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Disentangling the Taxonomy of Rickettsiales and Description of Two Novel Symbionts ("Candidatus Bealeia paramacronuclearis" and "Candidatus Fokinia cryptica") Sharing the Cytoplasm of the Ciliate Protist Paramecium biaurelia.

    Science.gov (United States)

    Szokoli, Franziska; Castelli, Michele; Sabaneyeva, Elena; Schrallhammer, Martina; Krenek, Sascha; Doak, Thomas G; Berendonk, Thomas U; Petroni, Giulio

    2016-12-15

    In the past 10 years, the number of endosymbionts described within the bacterial order Rickettsiales has constantly grown. Since 2006, 18 novel Rickettsiales genera inhabiting protists, such as ciliates and amoebae, have been described. In this work, we characterize two novel bacterial endosymbionts from Paramecium collected near Bloomington, IN. Both endosymbiotic species inhabit the cytoplasm of the same host. The Gram-negative bacterium "Candidatus Bealeia paramacronuclearis" occurs in clumps and is frequently associated with the host macronucleus. With its electron-dense cytoplasm and a distinct halo surrounding the cell, it is easily distinguishable from the second smaller symbiont, "Candidatus Fokinia cryptica," whose cytoplasm is electron lucid, lacks a halo, and is always surrounded by a symbiontophorous vacuole. For molecular characterization, the small-subunit rRNA genes were sequenced and used for taxonomic assignment as well as the design of species-specific oligonucleotide probes. Phylogenetic analyses revealed that "Candidatus Bealeia paramacronuclearis" clusters with the so-called "basal" Rickettsiales, and "Candidatus Fokinia cryptica" belongs to "Candidatus Midichloriaceae." We obtained tree topologies showing a separation of Rickettsiales into at least two groups: one represented by the families Rickettsiaceae, Anaplasmataceae, and "Candidatus Midichloriaceae" (RAM clade), and the other represented by "basal Rickettsiales," including "Candidatus Bealeia paramacronuclearis." Therefore, and in accordance with recent publications, we propose to limit the order Rickettsiales to the RAM clade and to raise "basal Rickettsiales" to an independent order, Holosporales ord. nov., inside Alphaproteobacteria, which presently includes four family-level clades. Additionally, we define the family "Candidatus Hepatincolaceae" and redefine the family Holosporaceae IMPORTANCE: In this paper, we provide the characterization of two novel bacterial symbionts

  8. Beberapa Marga Alga Benang dan Hubungannya dengan Keberadaan Vektor Malaria di Bali Utara

    OpenAIRE

    Seregeg, I. G

    1988-01-01

    A study of filamentous algae and its relation to malaria vector control was conducted during the dry season in several lagoons at the north coast of Bali. Floating masses of these algae under the sunshine barricated the spread of solar-triton larvicide, reducing tremendously the effectiveness of the larvicide. Identification of the genera of these algae under the subphyllum of CYANOPHYTA (Blue Algae) in the family of Cyanophyceae were Oscillatoria, Spirulina, Phormidium, Rivularia, Nostoc, an...

  9. Algae of economic importance that accumulate cadmium and lead: a review

    OpenAIRE

    Souza, Priscila O.; Ferreira, Lizângela R.; Pires, Natanael R. X.; S. Filho, Pedro J.; Duarte, Fabio A.; Pereira, Claudio M. P.; Mesko, Márcia F.

    2012-01-01

    Currently, algae and algae products are extensively applied in the pharmaceutical, cosmetic and food industries. Algae are the main organisms that take up and store heavy metals. Therefore, the use of compounds derived from algae by the pharmaceutical industry should be closely monitored for possible contamination. The pollution generated by heavy metals released by industrial and domestic sources causes serious changes in the aquatic ecosystem, resulting in a loss of biological diversity and...

  10. A review of the taxonomical and ecological studies on Netherlands’ Algae

    NARCIS (Netherlands)

    Koster, Joséphine Th.

    1939-01-01

    The earliest account of the Netherlands’ Algae appeared in 1781 in D. de Gorter, Flora VII Prov. Belgii foederati indigen. Here, however, in the Algae lichens and liverworts have been incorporated. The true Algae, of which 35 are enumerated, are principally marine, though also aërophytical and

  11. New methodologies for the integration of power plants with algae ponds

    NARCIS (Netherlands)

    Schipper, K.; Gijp, S. van der; Stel, R.W van der; Goetheer, E.L.V.

    2013-01-01

    It is generally recognized that algae could be an interesting option for reducing CO2 emissions. Based on light and CO2, algae can be used for the production various economically interesting products. Current algae cultivation techniques, however, still present a number of limitations. Efficient

  12. Abiotic Stress Tolerance of Charophyte Green Algae: New Challenges for Omics Techniques

    OpenAIRE

    Holzinger, Andreas; Pichrtov?, Martina

    2016-01-01

    Charophyte green algae are a paraphyletic group of freshwater and terrestrial green algae, comprising the classes of Chlorokybophyceae, Coleochaetophyceae, Klebsormidiophyceae, Zygnematophyceae, Mesostigmatophyceae, and Charo- phyceae. Zygnematophyceae (Conjugating green algae) are considered to be closest algal relatives to land plants (Embryophyta). Therefore, they are ideal model organisms for studying stress tolerance mechanisms connected with transition to land, one of the most important...

  13. Sexual reproduction and sex determination in green algae.

    Science.gov (United States)

    Sekimoto, Hiroyuki

    2017-05-01

    The sexual reproductive processes of some representative freshwater green algae are reviewed. Chlamydomonas reinhardtii is a unicellular volvocine alga having two mating types: mating type plus (mt + ) and mating type minus (mt - ), which are controlled by a single, complex mating-type locus. Sexual adhesion between the gametes is mediated by sex-specific agglutinin molecules on their flagellar membranes. Cell fusion is initiated by an adhesive interaction between the mt + and mt - mating structures, followed by localized membrane fusion. The loci of sex-limited genes and the conformation of sex-determining regions have been rearranged during the evolution of volvocine algae; however, the essential function of the sex-determining genes of the isogamous unicellular Chlamydomonas reinhardtii is conserved in the multicellular oogamous Volvox carteri. The sexual reproduction of the unicellular charophycean alga, Closterium peracerosum-strigosum-littorale complex, is also focused on here. The sexual reproductive processes of heterothallic strains are controlled by two multifunctional sex pheromones, PR-IP and PR-IP Inducer, which independently promote multiple steps in conjugation at the appropriate times through different induction mechanisms. The molecules involved in sexual reproduction and sex determination have also been characterized.

  14. On the pigment system of the red alga Porphyra Lacineata

    NARCIS (Netherlands)

    Thomas, J.B.; Marsman, J.W.

    1959-01-01

    Absorption and fluorescence around 725 mμ of suspensions of the red alga Porphyra lacineata were studied both with and without the phycobilins attached to the pigment system. The in vivo occurrence of 2 chlorophyll a types was confirmed spectroscopically. Their red absorption maxima are located at

  15. Algas vene kirjanduse nädal / Raimu Hanson

    Index Scriptorium Estoniae

    Hanson, Raimu, 1957-

    2008-01-01

    22. septembril algas Tartu Linnaraamatukogus vene kirjanduse nädal Inga Ivanova raamatu "Kadunud koerte saladus" esitlusega; 24. sept. toimub Igor Kotjuhi autoriõhtu; 26.-28. toimub Tartu Ülikoolis vene kirjandusele pühendatud rahvusvaheline teaduskonverents. Raamatukogust saab osta ka venekeelseid raamatuid

  16. Diversity of the Symbiotic Alga Symbiodinium in Tanzanian ...

    African Journals Online (AJOL)

    Abstract—With the current increase in frequency of coral bleaching events, knowledge on the genetic diversity of symbiotic algae in the genus Symbiodinium harboured by reef-building corals is important to understand how coral reefs will respond to global climate change. This study was undertaken as very little is known.

  17. Epiphytic Algae study from pool of Ammiq (Bekaa, Lebanon)

    International Nuclear Information System (INIS)

    SLIM, K.

    1984-01-01

    In this particular place which constitutes the pool of Ammiq, 104 species and varieties have been collected. The diatoms constitute in themselves 85% of the algae population. This is an epiphytic microflora which is attached to the immerged macrophytics on this above mentioned place . (author)

  18. Cytotoxic hydroazulene diterpenes from the brown alga Cystoseira myrica.

    Science.gov (United States)

    Ayyad, Seif-Eldin N; Abdel-Halim, Osama B; Shier, W Thomas; Hoye, Thomas R

    2003-01-01

    Cytotoxicity-guided fractionation of the alcohol extract of the brown alga, Cystoseira myrica, afforded four new cytotoxic hydroazulene diterpenes, dictyone acetate (2), dictyol F monoacetate (4), isodictytriol monoacetate (6), and cystoseirol monoacetate (8), together with two known cytotoxic hydroazulene diterpenes, pachydictyol A (1) and dictyone (3). The constitution of each isolated compound has been determined on the basis of spectroscopic and chemical evidence.

  19. Potential use of Algae Microcystis aeruginosa (Chroococaceae) in ...

    African Journals Online (AJOL)

    The test alga was subjected to growth medium with varying concentrations of petrol and kerosene. Algal growth was determined by measuring optical density of inoculated medium at three days' interval using a spectrophotometer at 750nm wavelength. The effect of the hydrocarbons on algal growth was either stimulatory or ...

  20. New records of brown algae (Phaeophyta) from the Azores.

    OpenAIRE

    Parente, Manuela I.; Fletcher, Robert L.; Neto, Ana I.

    2000-01-01

    Copyright © 2000 Kluwer Academic Publishers. Printed in the Netherlands. The following five species of microscopic tuft-forming/encrusting brown algae (Phaeophyta) are newly recorded for the Island of São Miguel (Azores): Nemoderma tingitana Schousboe ex Bornet. Pseudolithoderma roscoffense Loiseaux (Lithodermataceae), Hecatonema terminalis (Kutzing) Kylin (Punctariaceae), Compsonema saxicolum (Kuckuck) Kuckuck, and Microspongium gelatinosum Reinke (Scytosiphonaceae). The species are descr...

  1. FINE STRUCTURE AND ORGANELLE ASSOCIATIONS IN BROWN ALGAE

    Science.gov (United States)

    Bouck, G. Benjamin

    1965-01-01

    The structural interrelationships among several membrane systems in the cells of brown algae have been examined by electron microscopy. In the brown algae the chloroplasts are surrounded by two envelopes, the outer of which in some cases is continuous with the nuclear envelope. The pyrenoid, when present, protrudes from the chloroplast, is also surrounded by the two chloroplast envelopes, and, in addition, is capped by a third dilated envelope or "pyrenoid sac." The regular apposition of the membranes around the pyrenoid contrasts with their looser appearance over the remainder of the chloroplast. The Golgi apparatus is closely associated with the nuclear envelope in all brown algae examined, but in the Fucales this association may extend to portions of the cytoplasmic endoplasmic reticulum as well. Evidence is presented for the derivation of vesicles, characteristic of those found in the formative region of the Golgi apparatus, from portions of the underlying nuclear envelope. The possibility that a structural channeling system for carbohydrate reserves and secretory precursors may be present in brown algae is considered. Other features of the brown algal cell, such as crystal-containing bodies, the variety of darkly staining vacuoles, centrioles, and mitochondria, are examined briefly, and compared with similar structures in other plant cells. PMID:5865936

  2. Algae of the Bohemian Forest. 1. Specieses richness

    Czech Academy of Sciences Publication Activity Database

    Lederer, F.; Lukavský, Jaromír

    2001-01-01

    Roč. 6, - (2001), s. 97-104 ISSN 1211-7420 R&D Projects: GA AV ČR IA60504; GA ČR GA206/99/1411 Institutional research plan: CEZ:AV0Z6005908 Keywords : Bohemian Forest * species richness * biodiversity * algae * cyanobacteria * lakes * brooks * rivers * bogs Subject RIV: EH - Ecology, Behaviour

  3. Efficiency of using green algae as biological controllers against toxic ...

    African Journals Online (AJOL)

    Treatment I (untreated) served as a control, Treatment II was seeded with Microcystis aeruginosa, Treatment III was seeded with green algae Chlorella ellipsoidea and Scenedesmus bijuga, and Treatment IV was seeded with a mixture of M. aeruginosa and C. ellipsoidea and S. bijuga. After 10 days, Treatment IV showed ...

  4. Planktonic algae and cyanoprokaryotes as indicators of ecosystem ...

    African Journals Online (AJOL)

    To whom all correspondence should be addressed. ☎ +27 18 299-2517; fax: +27 18 299-2370; e-mail: 10066551@nwu.ac.za. Received 14 November 2012; accepted in revised form 7 October 2013. Planktonic algae and cyanoprokaryotes as indicators of ecosystem quality in the Mooi River system in the. North-West ...

  5. Symbiotic Blue Green Algae (Azolla): A Potential Bio fertilizer for ...

    African Journals Online (AJOL)

    Symbiotic Blue Green Algae (Azolla): A Potential Bio fertilizer for Paddy Rice Production in Fogera Plain, Northwestern Ethiopia. ... They were maintained and multiplied in plastic containers at Adet in a greenhouse and then inoculated into concrete tanks for testing their adaptability. Both strains were well adapted to Adet ...

  6. Rainfall changes affect the algae dominance in tank bromeliad ecosystems

    Science.gov (United States)

    Pires, Aliny Patricia Flauzino; Leal, Juliana da Silva; Peeters, Edwin T. H. M.

    2017-01-01

    Climate change and biodiversity loss have been reported as major disturbances in the biosphere which can trigger changes in the structure and functioning of natural ecosystems. Nonetheless, empirical studies demonstrating how both factors interact to affect shifts in aquatic ecosystems are still unexplored. Here, we experimentally test how changes in rainfall distribution and litter diversity affect the occurrence of the algae-dominated condition in tank bromeliad ecosystems. Tank bromeliads are miniature aquatic ecosystems shaped by the rainwater and allochthonous detritus accumulated in the bases of their leaves. Here, we demonstrated that changes in the rainfall distribution were able to reduce the chlorophyll-a concentration in the water of bromeliad tanks affecting significantly the occurrence of algae-dominated conditions. On the other hand, litter diversity did not affect the algae dominance irrespective to the rainfall scenario. We suggest that rainfall changes may compromise important self-reinforcing mechanisms responsible for maintaining high levels of algae on tank bromeliads ecosystems. We summarized these results into a theoretical model which suggests that tank bromeliads may show two different regimes, determined by the bromeliad ability in taking up nutrients from the water and by the total amount of light entering the tank. We concluded that predicted climate changes might promote regime shifts in tropical aquatic ecosystems by shaping their structure and the relative importance of other regulating factors. PMID:28422988

  7. Micro-algae: the Rise of Next Generation Biofuels

    CSIR Research Space (South Africa)

    Moodley, G

    2015-03-01

    Full Text Available stream_source_info Moodley_2015.pdf.txt stream_content_type text/plain stream_size 1163 Content-Encoding UTF-8 stream_name Moodley_2015.pdf.txt Content-Type text/plain; charset=UTF-8 Chapter 5 Micro-algae: the Rise...

  8. Seasonal abundance of epipelic algae and sediment parameters of ...

    African Journals Online (AJOL)

    Amadi-Ama creek is located close to sources of wastes which are introduced into the creek thus altering the physico-chemical parameters and the aquatic biota of the creek due to variation in nutrient load of the water. The seasonal abundance of epipelic algae and sediment parameters of Amadi-Ama Creek were ...

  9. Evaluation of Algae from the effluent of Dandot cement company ...

    African Journals Online (AJOL)

    Twenty genera and fifty species of algae have been reported from the effluent water of Dandot Cement Company. They include thirteen genera and thirty five species from Chlorophyceae; three genera and six species from Cyanophyceae and four genera and nine species from Bacillariophyceae. Camera Lucida drawings ...

  10. Preliminary Studies on the Occurrence of Freshwater Epipelic Algae ...

    African Journals Online (AJOL)

    The occurrence and composition of the freshwater algae in the epipelon were determined at three sites, namely Machigeni, Manhean and Weija, located in the coastal savanna thicket and grassland vegetation zone of the River Densu basin in southern Ghana. Samples of sediments from the water-substratum interface ...

  11. Prospective effect of red algae, Actinotrichia fragilis, against some ...

    African Journals Online (AJOL)

    Most of the current treatment strategies for OA are effective for symptoms relief but are accompanied with adverse side effect. Thus, the present investigation aims to evaluate the potential influence of red algae, Actinotrichia fragilis, in the dry powder form (AFP) or gel form (AFG) on some relevant factors of OA progression as ...

  12. Switchable photosystem-II designer algae for photobiological hydrogen production

    Science.gov (United States)

    Lee, James Weifu

    2010-01-05

    A switchable photosystem-II designer algae for photobiological hydrogen production. The designer transgenic algae includes at least two transgenes for enhanced photobiological H.sub.2 production wherein a first transgene serves as a genetic switch that can controls photosystem II (PSII) oxygen evolution and a second transgene encodes for creation of free proton channels in the algal photosynthetic membrane. In one embodiment, the algae includes a DNA construct having polymerase chain reaction forward primer (302), a inducible promoter (304), a PSII-iRNA sequence (306), a terminator (308), and a PCR reverse primer (310). In other embodiments, the PSII-iRNA sequence (306) is replaced with a CF.sub.1-iRNA sequence (312), a streptomycin-production gene (314), a targeting sequence (316) followed by a proton-channel producing gene (318), or a PSII-producing gene (320). In one embodiment, a photo-bioreactor and gas-product separation and utilization system produce photobiological H.sub.2 from the switchable PSII designer alga.

  13. Experimental analysis of the competition between algae and duckweed

    NARCIS (Netherlands)

    Roijackers, R.M.M.; Szabo, S.; Scheffer, M.

    2004-01-01

    We performed indoor competition experiments between algae and Lemna gibba L. in order to unravel mechanisms of competition. To separate effects of shading and physical interference from nutrient competition we grew the two groups physically separated while sharing the same water. A multifactorial

  14. Bioremediation of acid mine drainage using algae strains: A review

    Directory of Open Access Journals (Sweden)

    J.K. Bwapwa

    2017-12-01

    Full Text Available Acid mine drainage (AMD causes massive environmental concerns worldwide. It is highly acidic and contains high levels of heavy metals causing environmental damage. Conventional treatment methods may not be effective for AMD. The need for environmental remediation requires cost effective technologies for efficient removal of heavy metals. In this study, algae based systems were reviewed and analyzed to point out the potentials and gaps for future studies. Algae strains such as Spirulina sp., Chlorella, Scenedesmus, Cladophora, Oscillatoria, Anabaena, Phaeodactylum tricornutum have showed the capacity to remove a considerable volume of heavy metals from AMD. They act as “hyper-accumulators” and “hyper-adsorbents” with a high selectivity for different elements. In addition, they generate high alkalinity which is essential for precipitation of heavy metals during treatment. However, algae based methods of abating AMD are not the ultimate solution to the problem and there is room for more studies. : The bioremediation of acid mine drainage is achievable with the use of microalgae. Keywords: Acid mine drainage, Algae strains, Contamination, Heavy metals, Bioremediation

  15. The alga Trachydiscus minutus (Pseudostaurastrum minutum): growth and composition

    Czech Academy of Sciences Publication Activity Database

    Iliev, I.; Petkov, G.; Lukavský, Jaromír; Furnadzhieva, S.; Andreeva, R.; Bankova, V.

    2011-01-01

    Roč. 36, 3-4 (2011), 222-231 ISSN 1312-8183 R&D Projects: GA MŠk 1M0571 Institutional research plan: CEZ:AV0Z60050516 Keywords : algae, * fatty acids * pilot plant cultivation Subject RIV: EF - Botanics

  16. Removal of Algae in Stabilization Ponds Effluent using Moringa ...

    African Journals Online (AJOL)

    A number of studies have proved natural coagulants achieve high turbidity removal in water treatment. A pilot scale study was conducted to evaluate the effectiveness of natural coagulant (moringa oleifera) with respect to algae removal. Required effluent from stabilization ponds was diverted into the horizontal baffle ...

  17. Decreased abundance of crustose coralline algae due to ocean acidification

    Science.gov (United States)

    Kuffner, Ilsa B.; Andersson, Andreas J; Jokiel, Paul L.; Rodgers, Ku'ulei S.; Mackenzie, Fred T.

    2008-01-01

    Owing to anthropogenic emissions, atmospheric concentrations of carbon dioxide could almost double between 2006 and 2100 according to business-as-usual carbon dioxide emission scenarios1. Because the ocean absorbs carbon dioxide from the atmosphere2, 3, 4, increasing atmospheric carbon dioxide concentrations will lead to increasing dissolved inorganic carbon and carbon dioxide in surface ocean waters, and hence acidification and lower carbonate saturation states2, 5. As a consequence, it has been suggested that marine calcifying organisms, for example corals, coralline algae, molluscs and foraminifera, will have difficulties producing their skeletons and shells at current rates6, 7, with potentially severe implications for marine ecosystems, including coral reefs6, 8, 9, 10, 11. Here we report a seven-week experiment exploring the effects of ocean acidification on crustose coralline algae, a cosmopolitan group of calcifying algae that is ecologically important in most shallow-water habitats12, 13, 14. Six outdoor mesocosms were continuously supplied with sea water from the adjacent reef and manipulated to simulate conditions of either ambient or elevated seawater carbon dioxide concentrations. The recruitment rate and growth of crustose coralline algae were severely inhibited in the elevated carbon dioxide mesocosms. Our findings suggest that ocean acidification due to human activities could cause significant change to benthic community structure in shallow-warm-water carbonate ecosystems.

  18. The Belmont Valley integrated algae pond system in retrospect ...

    African Journals Online (AJOL)

    Integrated Algae Pond Systems (IAPS) are a derivation of the Oswald-designed Algal Integrated Wastewater Pond Systems (AIWPS®) and combine the use of anaerobic and aerobic bioprocesses to effect sewage treatment. IAPS technology was introduced to South Africa in 1996 and a pilot plant designed and ...

  19. Transesterification of oil extracted from different species of algae for ...

    African Journals Online (AJOL)

    In the current study, biodiesel production efficiency of Chlorella vulgaris, Rhizoclonium hieroglyphicum and mixed algae culture was measured by transesterification process. Growth rate of algal species was measured on the basis of increase in their dry matter in various media. Protein, carbohydrates and lipids in all ...

  20. Evaluation of filamentous green algae as feedstocks for biofuel production.

    Science.gov (United States)

    Zhang, Wei; Zhao, Yonggang; Cui, Binjie; Wang, Hui; Liu, Tianzhong

    2016-11-01

    Compared with unicellular microalgae, filamentous algae have high resistance to grazer-predation and low-cost recovery in large-scale production. Green algae, as the most diverse group of algae, included numerous filamentous genera and species. In this study, records of filamentous genera and species in green algae were firstly censused and classified. Then, seven filamentous strains subordinated in different genera were cultivated in bubbled-column to investigate their growth rate and energy molecular (lipid and starch) capacity. Four strains including Stigeoclonium sp., Oedogonium nodulosum, Hormidium sp. and Zygnema extenue were screened out due to their robust growth. And they all could accumulate triacylglycerols and starch in their biomass, but with different capacity. After nitrogen starvation, Hormidium sp. and Oedogonium nodulosum respectively exhibited high capacity of lipid (45.38% in dry weight) and starch (46.19% in dry weight) accumulation, which could be of high potential as feedstocks for biodiesel and bioethanol production. Copyright © 2016 Elsevier Ltd. All rights reserved.