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Sample records for flagellate heteromita globosa

  1. Katabia gromovi nov. gen., nov sp. - a new soil flagellate with affinities to Heteromita (Cercomonadida)

    DEFF Research Database (Denmark)

    Karpov, S.A.; Ekelund, Flemming; Moestrup, Øjvind

    2003-01-01

    Katabia gromovi, cercomonads, ultrastructure, cytoskeleton, soil flagellates, partial SSU gene sequence......Katabia gromovi, cercomonads, ultrastructure, cytoskeleton, soil flagellates, partial SSU gene sequence...

  2. The vitamin B requirement of Phaeocystis globosa (Prymnesiophyceae)

    NARCIS (Netherlands)

    Peperzak, L; Gieskes, WWC; Duin, R; Colijn, F

    In batch cultures of flagellates and non-flagellate cells of Phaeocystis globosa, the biomass yield was significantly enhanced by the addition of a mixture of the vitamins thiamine (B1), cyanocobalamin (B12) and biotin (H). A bioassay with B1 and B12 using the non-flagellate cells of P.globosa

  3. [Virulence of Sporothrix globosa in murine models].

    Science.gov (United States)

    Cruz Choappa, Rodrigo; Pérez Gaete, Salomón; Rodríguez Badilla, Valentina; Vieille Oyarzo, Peggy; Opazo Sanchez, Héctor

    The sporothricosis disease is an infection caused by species included in Sporothrix schenkii complex. Verify the virulence of a strain of S. globosa using two different concentrations of inoculum by intraperitoneally and subcutaneously, into a mouse model. Nonrandomized pilot study, in murine inoculated with a strain of S. globosa (CBS 14.076M) by intraperitoneally and subcutaneously with inoculum concentrations of 0.5 and 4 McFarland. For this purpose 18 rodents CF-1 (ISP, Santiago, Chile) were used. The studied strain did not induce illness or injury on animals, they all survived and neither the tissue culture nor the histopathological analysis showed fungal growth or suggestive infection by organ abnormalities. The S. globosa strain did not present any virulence enough to cause disease at 0.5 and 4.0 McFarland concentration inoculum when inoculated in both intraperitoneally and subcutaneously, in murine models. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. An analytical model of flagellate hydrodynamics

    DEFF Research Database (Denmark)

    Dölger, Julia; Bohr, Tomas; Andersen, Anders Peter

    2017-01-01

    solution by Oseen for the low Reynolds number flow due to a point force outside a no-slip sphere. The no-slip sphere represents the cell and the point force a single flagellum. By superposition we are able to model a freely swimming flagellate with several flagella. For biflagellates with left......–right symmetric flagellar arrangements we determine the swimming velocity, and we show that transversal forces due to the periodic movements of the flagella can promote swimming. For a model flagellate with both a longitudinal and a transversal flagellum we determine radius and pitch of the helical swimming......Flagellates are unicellular microswimmers that propel themselves using one or several beating flagella. We consider a hydrodynamic model of flagellates and explore the effect of flagellar arrangement and beat pattern on swimming kinematics and near-cell flow. The model is based on the analytical...

  5. Flagellate dermatitis following consumption of shiitake mushroom

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    Hui Voon Loo

    2011-10-01

    Full Text Available Japanese dermatologists were the first to describe the very characteristic flagellate dermatitis following consumption of under-cooked or raw shiitake mushroom (Lentinus edodes. These similar eruptions were also reported in patients treated with bleomycin, in dermatomyositis and adult onset Still’s disease. We report a case where a 40 year old chinese female developed flagellate dermatitis following ingestion of a bun containing shiitake mushroom.

  6. Renal flagellate infections in reptiles: 29 cases.

    Science.gov (United States)

    Juan-Sallés, Caries; Garner, Michael M; Nordhausen, Robert W; Valls, Xavier; Gallego, Miguel; Soto, Sara

    2014-03-01

    Renal infection with flagellated protozoa was retrospectively evaluated in 29 reptiles, including 12 turtles, 7 tortoises, and 6 chameleons; overall, 20 species of reptiles were represented. Most cases presented with nonspecific clinical signs or a combination of several concurrent diseases. Nineteen of 29 reptiles had tubulointerstitial nephritis associated with flagellates, and this lesion was considered contributory to death in 15 cases, although concurrent diseases were frequent. Infection was invasive into the renal interstitium in three reptiles due to tubular rupture and in one chameleon also spread to adjacent tissues, coelomic cavity, and blood vessels due to renal rupture. Cytologic or ultrastructural evaluation of trophozoites in two cases was consistent with diplomonad flagellates. Renal disease was often complicated with soft-tissue mineralization and/or gout. Gastrointestinal and cloacal infection with flagellates and inflammation were frequent in reptiles in which the digestive tract was available for histopathologic examination, and this supports the possibility of infections ascending the urinary tract from the cloaca. Renal disease associated with flagellate protozoa is rare in vertebrates but appears to be relevant in reptiles, particularly chelonians and chameleons.

  7. Putative bronchopulmonary flagellated protozoa in immunosuppressed patients.

    Science.gov (United States)

    Kilimcioglu, Ali Ahmet; Havlucu, Yavuz; Girginkardesler, Nogay; Celik, Pınar; Yereli, Kor; Özbilgin, Ahmet

    2014-01-01

    Flagellated protozoa that cause bronchopulmonary symptoms in humans are commonly neglected. These protozoal forms which were presumed to be "flagellated protozoa" have been previously identified in immunosuppressed patients in a number of studies, but have not been certainly classified so far. Since no human cases of bronchopulmonary flagellated protozoa were reported from Turkey, we aimed to investigate these putative protozoa in immunosuppressed patients who are particularly at risk of infectious diseases. Bronchoalveolar lavage fluid samples of 110 immunosuppressed adult patients who were admitted to the Department of Chest Diseases, Hafsa Sultan Hospital of Celal Bayar University, Manisa, Turkey, were examined in terms of parasites by light microscopy. Flagellated protozoal forms were detected in nine (8.2%) of 110 cases. Metronidazole (500 mg b.i.d. for 30 days) was given to all positive cases and a second bronchoscopy was performed at the end of the treatment, which revealed no parasites. In conclusion, immunosuppressed patients with bronchopulmonary symptoms should attentively be examined with regard to flagellated protozoa which can easily be misidentified as epithelial cells.

  8. Origin and distribution of Sporothrix globosa causing sapronoses in Asia.

    Science.gov (United States)

    Moussa, Tarek A A; Kadasa, Naif M S; Al Zahrani, Hassan S; Ahmed, Sarah Abdallah; Feng, Peiying; Gerrits van den Ende, Albertus H G; Zhang, Yu; Kano, Rui; Li, Fuqiu; Li, Shanshan; Song, Yang; Dong, Bilin; Rossato, Luana; Dolatabadi, Somayeh; Hoog, Sybren de

    2017-05-01

    The aim of the study was to evaluate the main sources and epidemiological patterns and speculate on the evolutionary origin of Sporothrix globosa in Asia. Case and case series literature on sporotrichosis in Asia from January 2007 onwards were reviewed using meta-analysis. Phylogenetic analysis of relevant S. globosa was carried out on the basis of concatenated sequences of ITS, TEF3 and CAL. A haplotype network of CAL sequences of 281 Sporothrix isolates was analysed to determine the population structure of S. globosa. Nearly all cases of sporotrichosis caused by S. globosa in Asia were human. In contrast to the remaining pathogenic Sporothrix species, feline transmission was exceptional; nearly all regional cat-associated cases were caused by Sporothrix schenckii. While the latter species was highly variable and showed recombination, S. globosa seemed to be a clonal offshoot, as was Sporothrix brasiliensis. The origin of the segregants was located in an area of high variability in S. schenckii with a relatively high frequency of Asian strains. In Asia, S. globosa was the prevalent species. The low diversity of S. globosa suggested a recent divergence with a founder effect of low variability from the variable ancestral species, S. schenckii.

  9. Prey capture by freely swimming flagellates

    Science.gov (United States)

    Andersen, Anders; Dolger, Julia; Nielsen, Lasse Tor; Kiorboe, Thomas

    2017-11-01

    Flagellates are unicellular microswimmers that propel themselves using one or several beating flagella. Here, we explore the dependence of swimming kinematics and prey clearance rate on flagellar arrangement and determine optimal flagellar arrangements and essential trade-offs. To describe near-cell flows around freely swimming flagellates we consider a model in which the cell is represented by a no-slip sphere and each flagellum by a point force. For uniflagellates pulled by a single flagellum the model suggests that a long flagellum favors fast swimming, whereas high clearance rate is favored by a very short flagellum. For biflagellates with both a longitudinal and a transversal flagellum we explore the helical swimming kinematics and the prey capture sites. We compare our predictions with observations of swimming kinematics, prey capture, and flows around common marine flagellates. The Centre for Ocean Life is a VKR Centre of Excellence supported by the Villum Foundation.

  10. An analytical model of flagellate hydrodynamics

    International Nuclear Information System (INIS)

    Dölger, Julia; Bohr, Tomas; Andersen, Anders

    2017-01-01

    Flagellates are unicellular microswimmers that propel themselves using one or several beating flagella. We consider a hydrodynamic model of flagellates and explore the effect of flagellar arrangement and beat pattern on swimming kinematics and near-cell flow. The model is based on the analytical solution by Oseen for the low Reynolds number flow due to a point force outside a no-slip sphere. The no-slip sphere represents the cell and the point force a single flagellum. By superposition we are able to model a freely swimming flagellate with several flagella. For biflagellates with left–right symmetric flagellar arrangements we determine the swimming velocity, and we show that transversal forces due to the periodic movements of the flagella can promote swimming. For a model flagellate with both a longitudinal and a transversal flagellum we determine radius and pitch of the helical swimming trajectory. We find that the longitudinal flagellum is responsible for the average translational motion whereas the transversal flagellum governs the rotational motion. Finally, we show that the transversal flagellum can lead to strong feeding currents to localized capture sites on the cell surface. (paper)

  11. The toxicity of the fungicide Propiconazole to soil flagellates

    DEFF Research Database (Denmark)

    Ekelund, Flemming; Westergaard, Kamma; Søe, Dorthe

    2000-01-01

    We investigated the effects of the ergosterol-inhibiting fungicide, propiconazole {1-[[2-(2,4-dichlorphenyl) - 4 - propyl - 1,3 - dioxolan - 2 - yl]methyl] - 1H - 1,2,4 triazole; Tilt}, on mixed natural populations of bacterivorous and fungivorous flagellates in soil and on single species...... of bacterivorous flagellates in liquid culture. The fungicide affected a mixed natural population of fungivorous flagellates less than the population of bacterivorous flagellates. Our results indicated that the effects of propiconazole on flagellates are direct toxic effects and not effects mediated via their food....... All tested types of flagellates were significantly harmed when exposed to the concentration of propiconazole normally applied to agricultural fields (625¿mg l-1). However, when exposed to the concentration of propiconazole which we expect in the soil water phase after application (ca. 0.6¿mg l-1...

  12. Numerical Simulations Of Flagellated Micro-Swimmers

    Science.gov (United States)

    Rorai, Cecilia; Markesteijn, Anton; Zaitstev, Mihail; Karabasov, Sergey

    2017-11-01

    We study flagellated microswimmers locomotion by representing the entire swimmer body. We discuss and contrast the accuracy and computational cost of different numerical approaches including the Resistive Force Theory, the Regularized Stokeslet Method and the Finite Element Method. We focus on how the accuracy of the methods in reproducing the swimming trajectories, velocities and flow field, compares to the sensitivity of these quantities to certain physical parameters, such as the body shape and the location of the center of mass. We discuss the opportunity and physical relevance of retaining inertia in our models. Finally, we present some preliminary results toward collective motion simulations. Marie Skodowska-Curie Individual Fellowship.

  13. First autochthone case of sporotrichosis by Sporothrix globosa in Portugal.

    Science.gov (United States)

    de Oliveira, Manoel Marques Evangelista; Veríssimo, Cristina; Sabino, Raquel; Aranha, João; Zancopé-Oliveira, Rosely Maria; Sampaio, Paula; Pais, Célia

    2014-04-01

    In this study, we characterize the first autochthone case of human sporotrichosis reported in Lisbon, Portugal. Phenotypic and genotypic characterization revealed that the infection was caused by Sporothrix globosa. We conclude that sporotrichosis may be underdiagnosed particularly in Southern Europe and suggest Portugal as an emerging area for this fungal infection. © 2014 Elsevier Inc. All rights reserved.

  14. Flavanones from aerial parts of Cordia globosa (Jacq. Kunth, Boraginaceae

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    Sâmia Andricia S. da Silva

    2010-07-01

    Full Text Available The phytochemical analysis of aerial parts of Cordia globosa, collected in the Municipality of Picuí, State of Paraíba, Brazil, resulted in the isolation and structural identification of narigenin-4',7-dimethyl ether (0.025 g and eriodictyol (0.015 g. These compounds are the first flavanones aglycones isolated from the genus Cordia.

  15. Trophic significance of solitary cells of the prymnesiophyte Phaeocystis globosa depends on cell type

    DEFF Research Database (Denmark)

    Dutz, Jörg; Koski, Marja

    2006-01-01

    With the use of five different isolates of Phaeocystis globosa solitary cells from the North Sea, we conducted experiments to reveal whether grazing and development of the nauplii of the calanoid copepod Temora longicornis varies in response to the cell type. Two P. globosa strains representing n...

  16. Whole-Genome Sequencing and In Silico Analysis of Two Strains of Sporothrix globosa

    NARCIS (Netherlands)

    Huang, Lilin; Gao, Wenchao; Giosa, Domenico; Criseo, Giuseppe; Zhang, Jing; He, Tailong; Huang, Xiaowen; Sun, Jiufeng; Sun, Yao; Huang, Jiamin; Zhang, Yunqing; Brankovics, Balázs; Scordino, Fabio; D'Alessandro, Enrico; van Diepeningen, Anne; de Hoog, Sybren; Huang, Huaiqiu; Romeo, Orazio

    2016-01-01

    Sporothrix globosa is a thermo-dimorphic fungus belonging to a pathogenic clade that also includes Sporothrix schenckii, which causes human and animal sporotrichosis. Here, we present the first genome assemblies of two S. globosa strains providing data for future comparative genomic studies in

  17. Selective grazing of Temora longicornis in different stages of a Phaeocystis globosa bloom - a mesocosm study

    DEFF Research Database (Denmark)

    Koski, Marja; Dutz, Jörg; Breteler, W.C.M.K.

    2005-01-01

    changes during the initiation, maintenance, collapse and decay of a P. globosa bloom and (3) if P. globosa dominated food assemblage provides a good diet for copepod egg production. Our results show low but constant feeding on small colonies of P. globosa, irrespective of the type or concentration...... of alternative food sources. In contrast, feeding on single cells was never significant, and the total contribution of P globosa to carbon ingestion of T longicornis was minor. T longicornis fed most actively on the decaying colonies, whereas during the peak of the bloom copepods selected against P globosa....... Mostly, T longicornis fed unselectively on different food particles: before the bloom, the major part of the diet consisted of diatoms, whereas during and after the bloom copepod diet was dominated by dinoflagellates and ciliates. Egg production was highest during the decay of the bloom, coinciding...

  18. Tolerance of soil flagellates to increased NaCl levels

    DEFF Research Database (Denmark)

    Ekelund, Flemming

    2002-01-01

    The ability of heterotrophic flagellates to survive and adapt to increasing salinities was investigated in this study. Whole soil samples were subjected to salinities corresponding to marine conditions and clonal cultures were used to perform growth and adaptation experiments at a wide range...... of different salinities (0-50 ppm). More morphotypes tolerant to elevated NaCl levels were found in road verge soil that was heavily exposed to de-icing salt than in less exposed soils, though there were fewer tolerant than intolerant morphotypes in all soils examined. Heterotrophic flagellates isolated...... on a freshwater medium from a non-exposed soil were unable to thrive at salinities above 15 ppt, and showed reduced growth rates even at low salt salinities (1-5 ppt). The findings suggest that heterotrophic soil flagellates are less tolerant to NaCl than their aquatic relatives, possibly due to their long...

  19. Shiitake Flagellate Dermatitis: the First Case Reported in Ireland

    LENUS (Irish Health Repository)

    Byrne, N

    2017-01-01

    Shiitake (Lentinula edodes) is the second most commonly consumed mushroom worldwide1. It is used in Asian medicine for its anticarcinogenic, antihypertensive and lipid lowering properties2. Furthermore, extracts of these mushrooms are used in over-the-counter dietary supplements designed to improve the immune system1. The first case of shiitake mushroom induced flagellate dermatitis was described in Japan in 1977 and it is now being reported in the western world3. After literary review and consultation with the Irish National Poisons Information Centre, we believe this is the first reported case of shiitake flagellate dermatitis in Ireland

  20. Some heterotrophic flagellates from a cultivated garden soil in Australia

    DEFF Research Database (Denmark)

    Ekelund, Flemming; Patterson, DJ

    1997-01-01

    The flagellates of an Australian garden soil were studied by placing coverslips on wet soil and subsequently examining the coverslips by light microscopy. A number of genera and species were found which have not previously been reported from soil samples. Besides the three new species, Apusomonas...

  1. A first report on a bloom of the marine prymnesiophycean, Phaeocystis globosa from the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Madhupratap, M.; Sawant, S.S.; Gauns, M.

    A thick bloom of the marine prymnesiophycean, Phaeocystis globosa was observed in the central Arabian Sea during the summer monsoon period (July-August, 1996). The cells were mostly in colonial form, embedded in gelatinous matrics. The cell diameter...

  2. 'David and Goliath' of the soil food web - Flagellates that kill nematodes

    DEFF Research Database (Denmark)

    Strandmark, Lisa Bjørnlund; Rønn, Regin

    2008-01-01

    Nematodes and flagellates are important bacterial predators in soil and sediments. Generally, these organisms are considered to be competitors for bacterial food. We studied the interaction among flagellates and nematodes using axenic liquid cultures amended with heat-killed bacteria as food...... and showed for the first time that a small and common soil flagellate (Cercomonas sp.) is able to attack and kill the much larger nematode Caenorhabditis elegans. The killing process is not caused by soluble metabolites but requires direct contact between the flagellate cells and the nematode surface...... and occurs rapidly (within a few hours) at high flagellate density. At lower flagellate density, adult nematodes sometimes avoid attachment of flagellates, feed on them and become the dominant bacterial predator. Considering that bacterial feeders affect bacterial communities differently, and that one...

  3. Phytochelatins play a key role in arsenic accumulation and tolerance in the aquatic macrophyte Wolffia globosa

    International Nuclear Information System (INIS)

    Zhang Xin; Uroic, M. Kalle; Xie Wanying; Zhu Yongguan; Chen Baodong; McGrath, Steve P.; Feldmann, Jörg; Zhao Fangjie

    2012-01-01

    The rootless duckweed Wolffia globosa can accumulate and tolerate relatively large amounts of arsenic (As); however, the underlying mechanisms were unknown. W. globosa was exposed to different concentrations of arsenate with or without L-buthionine sulphoximine (BSO), a specific inhibitor of γ-glutamylcysteine synthetase. Free thiol compounds and As(III)–thiol complexes were identified and quantified using HPLC – high resolution ICP-MS – accurate mass ESI-MS. Without BSO, 74% of the As accumulated in the duckweed was complexed with phytochelatins (PCs), with As(III)–PC 4 and As(III)–PC 3 being the main species. BSO was taken up by the duckweed and partly deaminated. The BSO treatment completely suppressed the synthesis of PCs and the formation of As(III)–PC complexes, and also inhibited the reduction of arsenate to arsenite. BSO markedly decreased both As accumulation and As tolerance in W. globosa. The results demonstrate an important role of PCs in detoxifying As and enabling As accumulation in W. globosa. - Highlights: ► W. globosa can accumulate and tolerate relatively large amounts of arsenic. ► Majority of the As accumulated in W. globosa was complexed with phytochelatins (PCs). ► As(III)–PC 4 and As(III)–PC 3 are the main complex species. ► Complexation of arsenite with phytochelatins plays a key role in As tolerance and accumulation. - Complexation of arsenite with phytochelatins plays a key role in both arsenic tolerance and accumulation in the aquatic macrophyte Wolffia globosa.

  4. A cytotoxic meroterpenoid benzoquinone from roots of Cordia globosa.

    Science.gov (United States)

    Alencar de Menezes, Jane Eire; Lemos, Telma Leda; Pessoa, Otília Deusdênia; Braz-Filho, Raimundo; Montenegro, Raquel C; Wilke, Diego Veras; Costa-Lotufo, Letícia V; Pessoa, Cláudia; de Moraes, Manoel Odorico; Silveira, Edilberto R

    2005-01-01

    (1a S*,1b S*,7a S*,8a S*)-4,5-Dimethoxy-1a,7a-dimethyl-1,1a,1b,2,7, 7a,8,8a-octahydrocyclopropa cyclopenta[1,2-b]naphthalene-3,6-dione (1), a new meroterpenoid benzoquinone, and microphyllaquinone (2), a known naphthoquinone, have been isolated from roots of Cordia globosa. Both structure determinations were performed by conventional spectroscopic methods, including inverse detection NMR techniques, and by comparison with data from the literature for related compounds. Compound 1 displayed considerable cytotoxic activity against several cancer cell lines with IC50 values in the range of 1.2 to 5.0 microg/mL. The cytotoxic activity seemed to be related to DNA synthesis inhibition, as revealed by the reduction of 5-bromo-2'-deoxyuridine incorporation, and apoptosis induction, as indicated by the acridine orange/ethidium bromide assay and morphological changes after 24 h of incubation on leukemic cells.

  5. The first case of isolation of malassezia globosa in our country

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    Arsić-Arsenijević Valentina S.

    2003-01-01

    Full Text Available Today is known that genus Malassezia includes seven species: M. furfur, M. sympodialis, M. obtusa, M. globosa, M. restricta, M. slooffiae and M. pachydermatis, but role of each of the species in the pathogenesis of desease has not been eluciated yet, so futher laboratory isolation and identification are necessary. We report the first case of isolation of Malassezia globosa in Serbia (Belgrade, in a patient suffering from Pityriasis versicolor. Identification of M. globosa was based on macroscopic, microscopic and biochemical characteristics. Isolation was done on Leeming and Notman medium and on mDixona agar, at 350C, during 7 days in aerobic conditions. Also the yeast's biochemical phenotype was determined as catalase (+, lipase (+, esculin degradation (-, Tween (20,40, 60 and 80 asimilation (-. M. globosa is a lipophilic yeast of the genus Malassezia and the common member of the skin flora. In concordance with some predis-poning factors M. globosa is implicated in the pathogenesis of several skin diseases (pityriasis versicolor, malassezia foliculitis sebor-rheic dermatitis and some forms of atopic dermatitis. In immuno-compromised patients and neonates this yeast can even cause fatal systemic infections. Because the role of Malassezia spp. in pathogenesis of skin desease is not still determined, we suggest laboratory diagnosis and identification of these species as a routine diagnostic procedure.

  6. Protistan Bacterivory in an Oligomesotrophic Lake: Importance of Attached Ciliates and Flagellates

    Science.gov (United States)

    Carrias; Amblard; Bourdier

    1996-05-01

    Seasonal and depth variations of the abundance, biomass, and bacterivory of protozoa (heterotrophic and mixotrophic flagellates and ciliates) were determined during thermal stratification in an oligomesotrophic lake (Lake Pavin, France). Maximal densities of heterotrophic flagellates (1.9x10(3) cells ml-1) and ciliates (6.1 cells ml-1) were found in the metalimnion. Pigmented flagellates dominated the flagellate biomass in the euphotic zone. Community composition of ciliated protists varied greatly with depth, and both the abundance and biomass of ciliates was dominated by oligotrichs. Heterotrophic flagellates dominated grazing, accounting for 84% of total protistan bacterivory. Maximal grazing impact of heterotrophic flagellates was 18.9x10(6) bacteria 1(-1)h-1. On average, 62% of nonpigmented flagellates were found to ingest particles. Ciliates and mixotrophic flagellates averaged 13% and 3% of protistan bacterivory, respectively. Attached protozoa (ciliates and flagellates) were found to colonize the diatom Asterionella formosa. Attached bacterivores had higher ingestion rates than free bacterivorous protozoa and may account for 66% of total protozoa bacterivory. Our results indicated that even in low numbers, epibiotic protozoa may have a major grazing impact on free bacteria.

  7. An inventory of factors that affect polysaccharide production by Phaeocystis globosa

    Science.gov (United States)

    van Rijssel, M.; Janse, I.; Noordkamp, D. J. B.; Gieskes, W. W. C.

    2000-08-01

    Phaeocystis material contains polysaccharides that are built from at least eight different monosaccharides. Differences have been reported between the carbohydrate composition of different Phaeocystis species, and also between samples taken from Phaeocystis globosa blooms in different areas. In order to elucidate factors that could play a role in determining variation in carbohydrate composition and production, a number of Phaeocystis globosa strains were studied under laboratory conditions. Although there was a clear distinction of a northern and a southern cluster in the Phaeocystis globosa strains based on RAPD analysis, the differences in the composition of the mucopolysaccharides were relatively small. The contribution of glucose, however, ranged from 7-85% of total sugars. A strain that was cultured in seawaters of diverse origin produced polysaccharides of a different composition, suggesting the effect of environmental factors. The presence of bacteria affected neither the amount, nor the composition of the carbohydrates that were produced by Phaeocystis globosa. Glucose is part of both the intracellular polysaccharide pool and of the mucopolysaccharides in the colony matrix. Using specific digestion of the intracellular chrysolaminaran by laminarinase, the distribution of polysaccharides over different pools could be assessed. During growth of an axenic, mucus-producing strain, the portion of glucose present as chrysolaminaran appeared to increase. The polyglucose that was not digested by laminarinase remains unidentified. This study shows that environmental factors rather than strain differences determine differences in the sugar composition of Phaeocystis globosa, especially with respect to the glucose content of the material. A difference in the contribution of glucose could be correlated to the portion of cells in the culture that are not in the colonies. Our study emphasises that for studying polysaccharide dynamics in Phaeocystis globosa it is

  8. Elemental mapping of As and other elements in rootless duckweed Wolffia globosa

    International Nuclear Information System (INIS)

    Zhang Xin; Chen Baodong; Luo Lei; Huang Qing; Zhu Yongguan

    2010-01-01

    Distribution of arsenic and the relationship with other elements in aquatic macrophytes Wolffia globosa is helpful in understanding mechanisms of arsenic accumulation and detoxification, which will be important for arsenic phytofiltration in contaminated water by aquatic macrophytes. In this paper, we study the distribution features of As and seven more elements in rootless duckweed Wolffia globosa by means of μXRF. The results indicated that the distribution of As was similar to that of K, Mn and Zn while differs from that of Cu, Fe, Ni and Ca. (authors)

  9. The Hidden Diversity of Flagellated Protists in Soil.

    Science.gov (United States)

    Venter, Paul Christiaan; Nitsche, Frank; Arndt, Hartmut

    2018-07-01

    Protists are among the most diverse and abundant eukaryotes in soil. However, gaps between described and sequenced protist morphospecies still present a pending problem when surveying environmental samples for known species using molecular methods. The number of sequences in the molecular PR 2 database (∼130,000) is limited compared to the species richness expected (>1 million protist species) - limiting the recovery rate. This is important, since high throughput sequencing (HTS) methods are used to find associative patterns between functional traits, taxa and environmental parameters. We performed HTS to survey soil flagellates in 150 grasslands of central Europe, and tested the recovery rate of ten previously isolated and cultivated cercomonad species, among locally found diversity. We recovered sequences for reference soil flagellate species, but also a great number of their phylogenetically evaluated genetic variants, among rare and dominant taxa with presumably own biogeography. This was recorded among dominant (cercozoans, Sandona), rare (apusozoans) and a large hidden diversity of predominantly aquatic protists in soil (choanoflagellates, bicosoecids) often forming novel clades associated with uncultured environmental sequences. Evaluating the reads, instead of the OTUs that individual reads are usually clustered into, we discovered that much of this hidden diversity may be lost due to clustering. Copyright © 2018 Elsevier GmbH. All rights reserved.

  10. Effectiveness of an anti-algal compound in eliminating an aquatic unicellular harmful algal Phaeocystis globosa

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    Huajun eZhang

    2016-04-01

    Full Text Available Phaeocystis globosa blooms can have negative effects on higher trophic levels in the marine ecosystem and consequently influence human activities. Strain KA22, identified as the bacterium Hahella, was isolated from coastal surface water and used to control P. globosa growth. A methanol extract from the bacteral cells showed strong algicidal activity. After purification, the compound showed a similar structure to prodigiosin when identified with Q-Exactive Orbitrap MS and nuclear magnetic resonance spectra. The compound showed algicidal activity against P. globosa with a 50% Lethal Dose (LD50 of 2.24 μg/mL. The prodigiosin was stable under heat and acid environment, and it could be degraded under alkaline environment and natural light condition. The growth rates of strain KA22 was fast in 2216E medium and the content of prodigiosin in this medium was more than 70 μg/mL after 16 h incubation. The compound showed particularly strong algicidal activity against Prorocentrum donghaiense, P. globosa and Heterosigma akashiwo, but having little effect on three other phytoplankton species tested. The results of our research could increase our knowledge on harmful algal bloom control compound and lead to further study on the mechanisms of the lysis effect on harmful algae.

  11. Temperature-dependent elimination efficiency on Phaeocystis globosa by different initial population sizes of rotifer Brachionus plicatilis.

    Science.gov (United States)

    Sun, Yunfei; Wang, Yuanyuan; Lei, Jin; Qian, Chenchen; Zhu, Xuexia; Akbar, Siddiq; Huang, Yuan; Yang, Zhou

    2018-07-01

    Due to sea water eutrophication and global warming, the harmful Phaeocystis blooms outbreak frequently in coastal waters, which cause a serious threat to marine ecosystem. The application of rotifer to control the harmful alga is a promising way. To investigate the influence of initial rotifer density and temperature on the ability of rotifer Brachionus plicatilis to eliminate Phaeocystis globosa population, we cultured P. globosa with different initial rotifer densities (1, 3, 5 inds mL -1 ) at 19, 22, 25, 28, and 31 °C for 9-16 d. Results showed that the population of rotifer feeding on Phaeocystis increased rapidly and higher temperatures favored the growth of P. globosa and B. plicatilis. With increased initial rotifer density and temperature, both the clearance rate of rotifer and the reduction rate of P. globosa increased, and thus P. globosa were eliminated earlier. Both temperature and initial rotifer density had significant effects on clearance rate of rotifer and the time to Phaeocystis extinction, and there was a significant interaction between the two factors on the two parameters, i.e., the effect of initial rotifer density on eliminating Phaeocystis decreased with increasing temperature. The rotifer in 5 inds mL -1 at 28 °C eliminated P. globosa in 4 d, whereas the rotifer in 1 ind mL -1 at 19 °C spent about 16 d on eliminating P. globosa. In conclusion, higher temperature and bigger initial rotifer density promote rotifer to eliminate the harmful P. globosa, and the optimal temperature for rotifer to clear P. globosa is 28 °C. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Fertilizer amendment for improving the phytoextraction of cadmium by a hyperaccumulator Rorippa globosa (Turcz.) Thell

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Shuhe; Zhou, Qixing X. [Chinese Academy of Sciences, Shenyang (China). Key Laboratory of Pollution Ecology and Environmental Engineering; Zhu, Jiangong [Chinese Academy of Sciences, Shenyang (China). Key Laboratory of Pollution Ecology and Environmental Engineering; Chinese Academy of Sciences, Beijing (China). Graduate School; Zhan, Jie [Institute of Liaoning Basic Medicine, Shenyang (China)

    2011-09-15

    Purpose: Two main pathways of phytoremediation of heavy metal-contaminated soils are phytostabilization and phytoextraction. Some soil amendments can strengthen phytostabilization or phytoextraction through either reducing heavy metal bioavailability in soil or increasing the heavy metal accumulation capacity of the hyperaccumulator (enhancing heavy metal concentration or shoot biomass of the hyperaccumulator). Urea and chicken manure are often used as fertilizers. This research will explore their effects on a newly found hyperaccumulator, Rorippa globosa (Turcz.) Thell., phytoremediating cadmium (Cd). Materials and methods: Pot culture experiment was conducted to study the accumulation characteristics of R. globosa at different Cd contamination concentrations under one fertilizer level (1 g kg{sup -1} for urea and 100 g kg{sup -1} for chicken manure), as well as the same Cd dose (20 mg kg{sup -1}) under different fertilizer doses. Cd was artificially spiked at 2.5, 5, 10, and 20 mg kg{sup -1}. Urea was amended at 0.5, 1, and 2 g kg{sup -1}, while chicken manure was supplemented at 50, 100, and 200 g kg{sup -1}. The heavy metal concentration in soil and plant samples was determined using an atomic absorption spectrophotometer. pH, N, P, K, and so on in soil samples were determined by normal method. Results and discussion: The results showed that urea application did not affect the Cd concentrations in root, stem, leaf, inflorescence, and shoot of R. globosa, but chicken manure significantly decreased (p < 0.05) them by 28.4%, 29.3%, 30.8%, 24.9%, and 28.3%, respectively, owing to decreased extractable Cd in soil. Thus, strengthening the capacity (Cd accumulation in plant shoot, micrograms per pot) of urea was higher than that of chicken manure, though both shoot biomasses increased by one to threefold. Furthermore, the addition of urea and chicken manure increased the organic material, nitrogen, phosphorus and potassium, the microorganism count, urease, and the

  13. Molecular epidemiology of human sporotrichosis in Venezuela reveals high frequency of Sporothrix globosa.

    Science.gov (United States)

    Camacho, Emma; León-Navarro, Isabel; Rodríguez-Brito, Sabrina; Mendoza, Mireya; Niño-Vega, Gustavo A

    2015-02-25

    Sporotrichosis is a cutaneous and subcutaneous fungal disease of humans and other mammals, known to be caused by the Sporothrix schenckii species complex, which comprises four species of clinical importance: S. brasiliensis, S. globosa, S. luriei, and S. schenckii sensu stricto. Of them, S. globosa and S. schenckii s. str. show global distribution and differences in global frequency as causal agents of the disease. In the Americas, only three species are present: S. schenckii s. str., S. brasiliensis (so far, only reported in Brazil), and S. globosa. In Venezuela, since the first case of sporotrichosis reported in 1935, S. schenckii have been considered its unique etiological agent. In the present work, the presence of more than one species in the country was evaluated. By phenotypic key features and molecular phylogeny analyses, we re-examined 30 isolates from diverse Venezuelan regions belonging to the fungi collection of Instituto de Biomedicina, Caracas, Venezuela, and national reference center for skin diseases. All isolates were collected between 1973 and 2013, and maintained in distilled water. Sporotrichosis in Venezuela is mainly caused by S. schenckii s. str. (70%). However, a significant proportion (30%) of sporotrichosis cases in the country can be attributable to S. globosa. A correlation between intraspecific genotypes and clinical presentation is proposed. Our data suggest that sporotrichosis various clinical forms might be related to genetic diversity of isolates, and possibly, to diverse virulence profiles previously reported in the S. schenckii species complex. Sporothrix globosa was found to be the causative agent of 30% of sporotrichosis for the Venezuelan cases re-examined, the highest frequency of this species so far reported in the Americas. The high genetic variability presented by S. schenckii s. str. indicates that species distinction based on phenotypic key features could be a challenging and uncertain task; molecular identification

  14. Cadmium accumulation in the rootless macrophyte Wolffia globosa and its potential for phytoremediation.

    Science.gov (United States)

    Xie, Wan-Ying; Huang, Qing; Li, Gang; Rensing, Christopher; Zhu, Yong-Guan

    2013-01-01

    Cadmium (Cd) pollution around the world is a serious issue demanding acceptable solutions, one of which is phytoremediation that is both cost-effective and eco-friendly. Removal of Cd from contaminated water using plants with high growth rates and sufficient Cd accumulation abilities could be an appropriate choice. Here, we investigated a potential Cd accumulator, Wolffia, a rootless duckweed with high growth rate. Cd uptake, accumulation, tolerance, and phytofiltration ability by Wolffia globosa were examined. Furthermore, the effects of arsenic (As) on Cd uptake and phytofiltration by W. globosa were also studied. Cd uptake kinetics showed a linear pattern and a hyperbolic pattern without a plateau in lower (0-2 microM) and higher (0-200 microM) Cd concentration ranges, respectively, suggesting rapid Cd uptake by W. globosa Cd accumulation ability by W. globosa was higher at Cd concentrations 10 microM. All the five species of Wolffia exposed to I microM Cd for 5 days accumulated > 500 mg Cd kg(-1) DW. Ten gram fresh W. globosa could diminish almost all the Cd (2 microM) in a 200 mL solution. This enormous accumulation ability was mostly due to passive adsorption of Cd by the apoplast. Arsenic had no significant effect on Cd uptake and phytofiltration. The fresh fronds also showed a great As extracting ability. The results indicated that Wolffia is a strong Cd accumulator and has great Cd phytoremediation potential. Therefore, this plant can be used in fresh aquatic environments co-contaminated by low-levels of Cd and As.

  15. Interaction of bacteria-feeding soil flagellates and Pseudomonas spp

    DEFF Research Database (Denmark)

    Pedersen, Annette; Ekelund, Flemming; Johansen, Anders

    2010-01-01

    Pseudomonas strains may be used as alternatives to fungicides as some of them produce secondary metabolites, which can inhibit growth of plant pathogenic fungi. Increased knowledge of non-target effects of the antagonistic bacteria on other soil organisms as well as of the survival and predation...... resistance of the antagonistic bacteria is necessary for risk assessment and increased performance of antagonistic bacteria as biological control agents. In the present study, we aimed to investigate the difference between Pseudomonas spp. with respect to their predation resistance to and effects...... on the three different and common soil flagellates Bodo caudatus, Cercomonas longicauda, and Neocercomonas jutlandica. Two antagonistic Pseudomonas: Pseudomonas fluorescens CHA0 and P. fluorescens DR54 and two positive control strains: P. fluorescens DSM 50090T and Pseudomonas chlororaphis ATCC 43928 were...

  16. Flagellation of Pseudomonas aeruginosa in newly divided cells

    Science.gov (United States)

    Zhao, Kun; Lee, Calvin; Anda, Jaime; Wong, Gerard

    2015-03-01

    For monotrichous bacteria, Pseudomonas aeruginosa, after cell division, one daughter cell inherits the old flagellum from its mother cell, and the other grows a new flagellum during or after cell division. It had been shown that the new flagellum grows at the distal pole of the dividing cell when the two daughter cells haven't completely separated. However, for those daughter cells who grow new flagella after division, it still remains unknown at which pole the new flagellum will grow. Here, by combining our newly developed bacteria family tree tracking techniques with genetic manipulation method, we showed that for the daughter cell who did not inherit the old flagellum, a new flagellum has about 90% chances to grow at the newly formed pole. We proposed a model for flagellation of P. aeruginosa.

  17. Cordiamyia globosa gen.n. e sp.n. (Diptera, Cecidomyiidae, Cecidomyiidi associado com Cordia Verbenacea DC. (Boraginaceae no Brasil Cordiamyia globosa gen.n. and sp.n. (Diptera, Cecidomyiidae associated with Cordia verbekacea DC. (Boraginaceae in Brazil

    Directory of Open Access Journals (Sweden)

    Valéria Cid Maia

    1996-01-01

    Full Text Available Cordiamyia globosa gen.n., sp.n. (Diptera, Cecidomyiidae, Cecidomyiidi associated with Cordia verbenacea (Boraginaceae, in Brazil, is described and illustrated (larva, pupa, male, female and gall.

  18. Diplomonad flagellates of some ornamental fish cultured in Thailand

    Directory of Open Access Journals (Sweden)

    Boonkob Viriyapongsutee

    2012-11-01

    Full Text Available The study on diplomonad flagellates infection in some ornamental fishes in the family cichlidae i.e., angelfish(Pterophyllum scalare, oscar (Astronotus ocellatus, blue mbuna (Labeotropheus fuelleborni and the family osphronemidaei.e., Siamese fighting fish (Betta splendens revealed that this parasite infected three out of four ornamental fish species,angelfish, oscar and blue mbuna. The highest infection was recorded in angelfish (90% followed by oscar (75.4% and bluembuna (61%, respectively. Identification of diplomonad flagellates from angelfish by means of morphological studies underlight and electron microscopes indicated that the parasite was Spironucleus vortens. The 14–days LD50 of S. vortens inangelfish was 2.99x103 cells. Histopathological changes of infected angelfish revealed granulomatous liver, numerousnumbers of melanomacrophage in the spleen and inflammation of the intestine. Susceptibility study of S. vortens to goldfish(Carassius auratus, guppy (Poecilia reticulata and platy (Xiphophorus maculatus indicated that they were resistant toartificial infection. In vitro examination of the growth inhibition assay of S. vortens indicated that dimetridazole and metronidazolewere effective in inhibiting parasite growth after 48 hrs exposure at concentrations of >4.0 μg/ml and >6.0 μg/ml,respectively. Magnesium sulfate at a concentration of >60 mg/ml inhibited the parasite growth after 72 hrs exposure. In vivoexamination of the dimetridazole efficiency on S. vortens infection indicated that dimetridazole at 4.0 μg/ml provided thehighest efficiency which could be used for treatment of spironucleosis in angelfish.

  19. Occurrence of swarms of Sagitta enflata (Chaetognatha) and Pleurobrachia globosa (Ctenophora) in the coastal waters of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, S.C.

    Swarms of Chaetognatha @iSagitta enflata@@ Grassi and Ctenophore @iPleurobrachia globosa@@. Moser were studied in coastal waters of Goa. These two forms together constituted 90 to 94% of total biomass. Medusae and Siphonophora were the other main...

  20. Microcystins do not provide anti-herbivore defence against mixotrophic flagellates

    NARCIS (Netherlands)

    Wilken, S.; Wiezer, S.M.H.; Huisman, J.; Van Donk, E.

    2010-01-01

    While most experiments investigating zooplankton grazing on harmful cyanobacteria have been carried out with metazoan plankton, several protozoa can also feed efficiently on cyanobacteria. We investigated grazing by the mixotrophic flagellate Ochromonas sp. on the toxic cyanobacterium Microcystis

  1. [Eye witnesses and the flagellants in the year 1349].

    Science.gov (United States)

    Jansen-Sieben, R

    1999-01-01

    Deeply affected and often desperately afraid, many contemporaries recorded their observations and emotions. These reports--no matter how obviously subjective they sometimes were--provide valuable information about what happened during the plague pandemic of 1348-1350. Thus many of our fellow countrymen left behind a direct testimony: Bartholomew of Bruges, a canon in Andenne; Gilles li Muisis, the abbot of Saint Martin in Tournai; Ludovicus Sanctus of Beringen; Simon de Couvin, a canon in Liège; Jan van Boendale, an alderman's clerk in Antwerp; John of Burgundy (also known as John of Mandeville), professor of medicine in Liège; but also texts in Middle Dutch that were not known up to now, and therefore not published, such as the important thesis by Arent Schryver, licentiate in medicine (see next article); an account in verse in the Brabant Chronicle, as well as contemporary testimonies in a different language that have been translated into our language, such as that by John of Eschinden, Johannes de Rupescissa or Guy de Chauliac (who had had the plague himself). They describe the precautions, the causes (God, a comet, an eclipse of the sun, the polluted water, the planets, the air), the symptoms, the social groups most likely to be affected (the youth, the lower classes, the clergy), the high mortality, the problems of hygiene,the social and administrative chaos, the general panic, the flight of countless people. One of the most virulent reactions led to the emergence of the flagellant sect. They originated from Hungary and advanced in an unstoppable advance with a growing number of followers as far as our country, singing, praying, dancing and flaying themselves until they drew blood. We only recently discovered what they sang in Dutch: very recently, a unique roll of parchment was discovered that they carried in their processions, and that contains the text of their songs and a flagellant sermon. The existence of this valuable document and its contents are

  2. Differential freshwater flagellate community response to bacterial food quality with a focus on Limnohabitans bacteria

    Czech Academy of Sciences Publication Activity Database

    Šimek, Karel; Kasalický, Vojtěch; Jezbera, Jan; Horňák, Karel; Nedoma, Jiří; Hahn, M.W.; Bass, D.; Jost, S.; Boenigk, J.

    2013-01-01

    Roč. 7, č. 8 (2013), s. 1519-1530 ISSN 1751-7362 R&D Projects: GA ČR(CZ) GA13-00243S; GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : flagellate community composition * food quality of bacteria * Limnohabitans * 454 pyrosequencing * freshwater * flagellate growth Subject RIV: DA - Hydrology ; Limnology Impact factor: 9.267, year: 2013

  3. Antinociceptive activity of Buddleja globosa (matico) in several models of pain.

    Science.gov (United States)

    Backhouse, Nadine; Delporte, Carla; Apablaza, Cecia; Farías, Mariela; Goïty, León; Arrau, Sylvia; Negrete, Rosa; Castro, Consuelo; Miranda, Hugo

    2008-09-02

    Leaf extracts of Buddleja globosa (Buddlejaceae) are used in Chilean folk medicine for wound healing. The anti-inflammatory (topic and per os), analgesic (per os) effects and the antioxidant activity of Buddleja globosa were for the first time reported by us. Assess the antinociceptive activity of the methanol sequential and global extracts using complementary chemical and thermal models of pain, characterize pharmacologically the antinociception induced, evaluate seasonal influence to support Buddleja globosa medicinal use. Global methanol, sequential methanol and ethanol (leaves collected in autumn and summer) extracts were evaluated for oral and topic analgesia in tail flick, formalin and writhing models, verbascoside and 7-O-luteolin glucoside were assayed in tail flick and writhing. Ibuprofen was used as reference. For characterization of induced antinociception, naltrexone, naltrindole, tropisetron, nor-binaltorphimine, prazosin, yohimbine, atropine, and N-nitro-l-arginine methyl ester were used as antagonists and inhibitors drugs. Seasonal influence was observed since autumn extract resulted less active. Extracts showed a dose-dependent antinociceptive activity in all assays, the highest effects were obtained for the formalin and writhing test. Verbascoside was more active than ibuprofen in the writhing test (67.6% and 50.0% at equimolar doses) and showed similar effects in the tail flick (topic and oral) near 25% at equivalent doses - ED25 or EC25 - to ibuprofen. Luteolin 7-O-glucoside was slightly more active in the tail flick test and nearly half active than verbascoside in the writhing assay. Effectiveness was higher for the sequential than for global alcoholic extracts, and can be increased by selective blocking of opioid receptors. Global methanol extract seems modulated only by naltrexone. Analgesic effect of Buddleja globosa is here demonstrated validating its use in traditional medicine. Season influence is important to be considered.

  4. Toxic Effects of Prodigiosin Secreted by Hahella sp. KA22 on Harmful Alga Phaeocystis globosa

    Directory of Open Access Journals (Sweden)

    Huajun Zhang

    2017-06-01

    Full Text Available Application of algicidal compounds secreted by bacteria is a promising and environmentally friendly strategy to control harmful algal blooms (HABs. Years ago prodigiosin was described as an efficient algicidal compound, but the details about the effect of prodigiosin on algal cells are still elusive. Prodigiosin shows high algicidal activity on Phaeocystis globosa, making it a potential algicide in HAB control. When P. globosa were treated with prodigiosin at 5 μg/mL, algae cells showed cytoplasmic hypervacuolization, chloroplast and nucleus rupture, flagella missing, and cell fracture, when observed by scanning electron microscope and transmission electron microscopy. Prodigiosin induced a reactive oxygen species (ROS burst in P. globosa at 2 h, which could result in severe oxidative damage to algal cells. Chlorophyll a (Chl a fluorescence decreased significantly after prodigiosin treatment; about 45.3 and 90.0% of algal cells lost Chl a fluorescence at 24 and 48 h. The Fv/Fm value, reflecting the status of the photosystem II electron flow also decreased after prodigiosin treatment. Quantitative polymerase chain reaction (PCR analysis psbA and rbcS expression indicated that photosynthesis process was remarkably inhibited by prodigiosin. The results indicated that the inhibition of photosynthesis may produce excessive ROS causing cell necrosis. This study is the first report about algal lysis mechanism of prodigiosin on harmful algae. Our results could increase our knowledge on the interaction between algicidal compounds and harmful algae, which could lead to further studies in the microcosm.

  5. An In Vitro Study of the Antioxidant and Antihemolytic Properties of Buddleja globosa (Matico).

    Science.gov (United States)

    Suwalsky, Mario; Duguet, José; Speisky, Hernán

    2017-06-01

    The antioxidant and antihemolytic properties contained in the leaves of Buddleja globosa (B. globosa), also known as "Matico," were determined. Aqueous extracts of leaves were assayed in human erythrocytes and molecular models of its membrane. The latter were bilayers built-up of lipids located in the outer and inner leaflets of the erythrocyte membrane. Observations by scanning electron microscopy showed that the extract altered the morphology of erythrocytes inducing the formation of crenated echinocytes. This result implied that the extract components were inserted into the outer leaflet of the cell membrane. This conclusion was confirmed by experiments carried out by fluorescence spectroscopy of red cell membranes and vesicles (LUV) of dimyristoylphosphatidylcholine (DMPC) and by X-ray diffraction of DMPC and dimyristoylphosphatidylethanolamine bilayers. Human erythrocytes were in vitro exposed to HClO, which is a natural powerful oxidant. Results demonstrated that low concentrations of B. globosa aqueous extract neutralized the harmful capacity of HClO. Hemolysis experiments also showed that the extract in very low concentrations reduced hemolysis induced by HClO.

  6. Characterizing the interactions among a dinoflagellate, flagellate and bacteria in the phycosphere of Alexandrium tamarense (Dinophyta

    Directory of Open Access Journals (Sweden)

    Lidan eHu

    2015-11-01

    Full Text Available A small flagellate alga was isolated from the phycosphere of a toxic red tide dinoflagellate Alexandrium tamarense. Phylogenetic analysis and ultrastructural observations demonstrated that the samll flagellate alga is a species belong to Ochrophyte Ochromonas sp. The process of ingesting bacteria by Ochromonas sp. was recorded by a time lapse capture under a light microscope. Through the use of different assemblages in the co-culture experiment, the species interactions in this phycosphere microenvironment were analyzed. We demonstrated that the growth of Ochromonas sp. was supported by bacteria. Three strains of bacteria ingested by Ochromonas sp. were isolated and identified to belong to α-, δ- and γ-Proteobacteria. The growth of A. tamarense was suppressed when co-cultured with bacteria. In contrast, Ochromonas sp. triggered the growth of A. tamarense by inhibiting the growth of algicidal bacteria. This result firstly demonstrated a positive effect of a flagellate on a dinoflagellate in the phycosphere of A. tamarense. Combined with other negative effects between dinoflagellates and bacteria or bacteria and flagellates, this study showed a series of clear interactions among dinoflagellate, bacterium, and flagellate in the dinoflagellate microenvironment.

  7. Sporotrichosis caused by Sporothrix globosa in Rio De Janeiro, brazil: case report.

    Science.gov (United States)

    de Oliveira, Manoel Marques Evangelista; de Almeida-Paes, Rodrigo; de Medeiros Muniz, Mauro; de Lima Barros, Monica Bastos; Galhardo, Maria Clara Gutierrez; Zancope-Oliveira, Rosely Maria

    2010-05-01

    This report describes the first isolation of Sporothrix globosa from a Brazilian patient. A 77-year-old woman was examined for sporotrichosis infection. Histopathological examination of skin biopsy revealed chronic granulomatous infiltrate with microabcess. Furthermore, S. schenckii-like yeasts were evident as demonstrated by PAS and Grocott stains. The fungus was identified based on colony morphology on Sabouraud Dextrose Agar slants, Potato Dextrose Agar, and Corn Meal Agar, microscopic morphology on slides cultures, and assimilation of different carbon sources. The species confirmation was made by molecular methodology.

  8. Negative consequences of glacial turbidity for the survival of freshwater planktonic heterotrophic flagellates.

    Science.gov (United States)

    Sommaruga, Ruben; Kandolf, Georg

    2014-02-17

    Heterotrophic (phagotrophic) flagellates are key components of planktonic food webs in freshwater and marine ecosystems because they are the main consumers of bacteria. Although they are ubiquitous in aquatic ecosystems, they were numerically undetectable in turbid glacier-fed lakes. Here we show that glacial particles had negative effects on the survival and growth of heterotrophic flagellates. The effect of glacial particles was concentration-dependent and was caused by their interference with bacterial uptake rather than by physical damage. These results are the first to reveal why establishment of heterotrophic flagellates populations is hindered in very turbid glacial lakes. Because glaciers are vanishing around the world, recently formed turbid meltwater lakes represent an excellent opportunity to understand the environmental conditions that probably shaped the establishment of lake communities at the end of the last glaciation.

  9. Particle-associated flagellates: swimming patterns, colonization rates, and grazing on attached bacteria

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Grossart, H.P.; Ploug, H.

    2004-01-01

    Some pelagic flagellates colonize particles, such as marine snow, where they graze on bacteria and thus impact the dynamics of the attached microbial communities. Particle colonization is governed by motility. Swimming patterns of 2 particle-associated flagellates, Bodo designis and Spumella sp......., are very different, the former swimming slowly in an erratic, random pattern, and the latter faster and along smooth helixes of variable amplitude and frequency. At spatial scales exceeding ca. 50 mum, the motility of B. designis can be described as a random walk and modeled as diffusion. Spumella sp...

  10. A study of the soil flagellate Phalansterium solitarium Sandon 1924 with preliminary data on its ultrastructure

    DEFF Research Database (Denmark)

    Ekelund, Flemming

    2002-01-01

    Phalansterium solitarium Sandon 1924, a common soil flagellate, was isolated and a Sandon 1924, a common soil flagellate, was isolated and a clonal culture was examined using light and electron microscopy. The first preliminary observations of its ultrastructure show that the cells of Ph....... solitarium have the same main characters as an earlier investigated species of the genus, Ph. digitatum Stein 1878, including a collarlike structure surrounding the basis of the single emerging flagellum, tubular cristae, a single basal body, surrounded by x, y and z zones with radiating microtubules...

  11. Atypical Clinical Presentation of Sporotrichosis Caused by Sporothrix globosa Resistant to Itraconazole.

    Science.gov (United States)

    Fischman Gompertz, Olga; Rodrigues, Anderson M; Fernandes, Geisa F; Bentubo, Henri D L; de Camargo, Zoilo Pires; Petri, Valéria

    2016-06-01

    Sporotrichosis is a polymorphic disease of humans and animals, which is acquired via traumatic inoculation of Sporothrix propagules into cutaneous or subcutaneous tissue. The etiological agents are in a clinical complex, which includes Sporothrix brasiliensis, Sporothrix schenckii, Sporothrix globosa, and Sporothrix luriei, each of which has specific epidemiological and virulence characteristics. Classical manifestation in humans includes a fixed localized lesion at the site of trauma plus lymphocutaneous sporotrichosis with fungal spreading along the lymphatic channels. Atypical sporotrichosis is a challenge to diagnosis because it can mimic many other dermatological diseases. We report an unusual, itraconazole-resistant cutaneous lesion of sporotrichosis in a 66-year-old Brazilian man. Histopathological examination of the skin revealed vascular and fibroblastic proliferation with chronic granulomatous infiltrate composed of multinucleated giant cells. Sporothrix were isolated from the skin lesion, and phylogenetic analyses confirmed it to be sporotrichosis due to S. globosa, a widespread pathogen. Immunoblotting analysis showed several IgG-reactive molecules in autochthonous preparations of the whole cellular proteins (160, 80, 60, 55, 46, 38, 35, and 30 kDa) and exoantigen (35 and 33 kDa). The patient was first unsuccessfully treated with daily itraconazole, and then successfully treated with potassium iodide. © The American Society of Tropical Medicine and Hygiene.

  12. CHANGES IN THE MORPHOLOGY AND POLYSACCHARIDE CONTENT OF MICROCYSTIS AERUGINOSA (CYANOBACTERIA) DURING FLAGELLATE GRAZING(1).

    Science.gov (United States)

    Yang, Zhou; Kong, Fanxiang; Shi, Xiaoli; Zhang, Min; Xing, Peng; Cao, Huansheng

    2008-06-01

    To investigate the changes in the morphology and polysaccharide content of Microcystis aeruginosa (Kütz.) Kütz. during flagellate grazing, cultures of M. aeruginosa were exposed to grazing Ochromonas sp. for a period of 9 d under controlled laboratory conditions. M. aeruginosa responded actively to flagellate grazing and formed colonies, most of which were made up of several or dozens of cells, suggesting that flagellate grazing may be one of the biotic factors responsible for colony formation in M. aeruginosa. When colonies were formed, the cell surface ultrastructure changed, and the polysaccharide layer on the surface of the cell wall became thicker. This change indicated that synthesis and secretion of extracellular polysaccharide (EPS) of M. aeruginosa cells increased under flagellate grazing pressure. The contents of soluble extracellular polysaccharide (sEPS), bound extracellular polysaccharide (bEPS), and total polysaccharide (TPS) in colonial cells of M. aeruginosa increased significantly compared with those in single cells. This finding suggested that the increased amount of EPS on the cell surface may play a role in keeping M. aeruginosa cells together to form colonies. © 2008 Phycological Society of America.

  13. Effects of Buddleja globosa leaf and its constituents relevant to wound healing.

    Science.gov (United States)

    Mensah, A Y; Sampson, J; Houghton, P J; Hylands, P J; Westbrook, J; Dunn, M; Hughes, M A; Cherry, G W

    2001-10-01

    An aqueous extract of Buddleja globosa leaves, used traditionally in Chile for wound healing, was tested for the ability to stimulate growth of fibroblasts in vitro and for antioxidant activity in the same fibroblast cell system challenged with hydrogen peroxide. Low concentrations of the extract gave an increase in fibroblast growth which was not statistically significant but cytotoxicity was observed at concentrations greater than 50 microg/ml. The extract showed strong antioxidant effect and fractionation led to the isolation of three flavonoids and two caffeic acid derivatives, each of which was shown to contribute to the antioxidant effect at concentrations below 10 microg/ml. These activities would accelerate the healing of wounds.

  14. Toxic effect of a marine bacterium on aquatic organisms and its algicidal substances against Phaeocystis globosa.

    Directory of Open Access Journals (Sweden)

    Qiuchan Yang

    Full Text Available Harmful algal blooms have caused enormous damage to the marine ecosystem and the coastal economy in China. In this paper, a bacterial strain B1, which had strong algicidal activity against Phaeocystis globosa, was isolated from the coastal waters of Zhuhai in China. The strain B1 was identified as Bacillus sp. on the basis of 16S rDNA gene sequence and morphological characteristics. To evaluate the ecological safety of the algicidal substances produced by strain B1, their toxic effects on marine organisms were tested. Results showed that there were no adverse effects observed in the growth of Chlorella vulgaris, Chaetoceros muelleri, and Isochrystis galbana after exposure to the algicidal substances at a concentration of 1.0% (v/v for 96 h. The 48h LC50 values for Brachionus plicatilis, Moina mongolica Daday and Paralichthys olivaceus were 5.7, 9.0 and 12.1% (v/v, respectively. Subsequently, the algicidal substances from strain B1 culture were isolated and purified by silica gel column, Sephadex G-15 column and high-performance liquid chromatography. Based on quadrupole time-of-flight mass spectrometry and PeakView Software, the purified substances were identified as prolyl-methionine and hypoxanthine. Algicidal mechanism indicated that prolyl-methionine and hypoxanthine inhibited the growth of P. globosa by disrupting the antioxidant systems. In the acute toxicity assessment using M. mongolica, 24h LC50 values of prolyl-methionine and hypoxanthine were 7.0 and 13.8 g/L, respectively. The active substances produced by strain B1 can be considered as ecologically and environmentally biological agents for controlling harmful algal blooms.

  15. Prey-specific growth responses of freshwater flagellate communities induced by morphologically distinct bacteria from the genus Limnohabitans

    Czech Academy of Sciences Publication Activity Database

    Grujčič, Vesna; Kasalický, Vojtěch; Šimek, Karel

    2015-01-01

    Roč. 81, č. 15 (2015), s. 4993-5002 ISSN 0099-2240 R&D Projects: GA ČR(CZ) GA13-00243S; GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : freshwater reservoir * heterotrophic flagellate bacterivory * Limnohabitans * bacterial food quality * growth responses of flagellates Subject RIV: EH - Ecology, Behaviour Impact factor: 3.823, year: 2015

  16. The different response mechanisms of Wolffia globosa: Light-induced silver nanoparticle toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Xiaoyan; Li, Penghui [Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Huang, Qing [Key Laboratory of Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Zhang, Hongwu, E-mail: hwzhang@iue.ac.cn [Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China); Ningbo Research Center for Urban Environment, Chinese Academy of Sciences, Ningbo (China)

    2016-07-15

    Highlights: • The different physiological responses of AgNPs in Wolffia golbosa were studied. • Effects of AgNPs on W. golbosa relied on the illumination conditions. • Different phytotoxic mechanisms of AgNPs for different light schemes were proposed. - Abstract: Silver nanoparticles (AgNPs) have emerged as a promising bactericide. Plants are a major point of entry of contaminants into trophic chains. Here, the physiological responses of Wolffia globosa to AgNPs have been probed using different light schemes, and these data may reveal new insights into the toxic mechanism of AgNPs. W. globosa was grown in culture medium and treated with different concentrations of AgNPs for 24 h under pre- and post-illuminated conditions. However, fluorescence quenching, the accumulation of sugar and the reduction of Hill reaction activity were found in response to the AgNP-stresses. In the pre-illuminated condition, oxidative damage was obvious, as indicated by the higher malondialdehyde (MDA) content and an up-regulation of superoxide dismutase (SOD) activity. The maximum increases of MDA content and SOD activity were 1.14 and 2.52 times the respective controls when exposed to 10 mg/L AgNPs. In contrast, in the post-illuminated condition, the alterations in photosynthetic pigment and soluble proteins content were more significant than the alterations in oxidative stress. The contents of chlorophyll a, carotenoids and soluble protein decreased to 77.7%, 66.2% and 72.9% of the controls after treatment with the highest concentration of AgNPs (10 mg/L). Based on the different physiological responses, we speculated that in the pre-illuminated condition, oxidative stress was responsible for the decline in the oxygen evolution rate, while in the post-illuminated condition, the decrease in the Hill reaction activity could be attributed to the blocking of electron transfer and an insufficient proton supply. Our findings demonstrate that environmental factors regulate the

  17. Analgesic, anti-inflammatory and antioxidant properties of Buddleja globosa, Buddlejaceae.

    Science.gov (United States)

    Backhouse, N; Rosales, L; Apablaza, C; Goïty, L; Erazo, S; Negrete, R; Theodoluz, C; Rodríguez, J; Delporte, C

    2008-03-05

    Buddleja globosa, known as "matico", is employed in Chile for wound healing. To validate the traditional use of the crude drug through in vivo and in vitro evaluation of the anti-inflammatory, analgesic and antioxidant properties of its extracts. Sequential hexane, dichloromethane, methanol and total methanol extracts were studied using bioguided fractionation. The following activities were investigated: analgesic (writhing test), oral and topic anti-inflammatory (paw- and ear-induced edema), free radical scavenging and antioxidant activities (1,1-diphenyl-2-picrylhydrazyl, DPPH, superoxide anion, lipid peroxidation and xanthine oxidase inhibition). Sodium naproxen, nimesulide, indomethacin were used as reference drugs for in vivo, quercetin and allopurinol for in vitro assays. A mixture of alpha- and beta-amyrins was isolated from the hexane extract that showed 41.2% of analgesic effect at 600 mg/kg, inhibited by 47.7 and 79.0% the arachidonic acid (AA) and 12-deoxyphorbol-13-decanoate (TPA)-induced inflammation at 3mg/20 microL/ear, respectively. A mixture of beta-sitosterol, stigmasterol, stigmastenol, stigmastanol and campesterol was isolated from the fraction CD4-N and beta-sitosterol-glycoside from the fraction CD5-N, reducing TPA-induced inflammation by 78.2 and 83.7% at 1mg/20 microL/ear, respectively. The fraction CD4-N at 300 mg/kg also showed analgesic activity (38.7%). The methanol extract at 600mg/kg per os showed anti-inflammatory effect (61.4%), topic anti-inflammatory (56.7% on TPA) and analgesic activity (38.5%). Verbascoside and luteolin-7-O-glucoside were the major components of the methanol extract; apigenin 7-O-glucoside was also detected. Inhibition of superoxide anion, lipoperoxidation, and DPPH bleaching effect was found in the methanol serial and global extracts. The present report demonstrate the analgesic and anti-inflammatory properties of Buddleja globosa and validate its use in Chilean traditional medicine.

  18. The different response mechanisms of Wolffia globosa: Light-induced silver nanoparticle toxicity

    International Nuclear Information System (INIS)

    Zou, Xiaoyan; Li, Penghui; Huang, Qing; Zhang, Hongwu

    2016-01-01

    Highlights: • The different physiological responses of AgNPs in Wolffia golbosa were studied. • Effects of AgNPs on W. golbosa relied on the illumination conditions. • Different phytotoxic mechanisms of AgNPs for different light schemes were proposed. - Abstract: Silver nanoparticles (AgNPs) have emerged as a promising bactericide. Plants are a major point of entry of contaminants into trophic chains. Here, the physiological responses of Wolffia globosa to AgNPs have been probed using different light schemes, and these data may reveal new insights into the toxic mechanism of AgNPs. W. globosa was grown in culture medium and treated with different concentrations of AgNPs for 24 h under pre- and post-illuminated conditions. However, fluorescence quenching, the accumulation of sugar and the reduction of Hill reaction activity were found in response to the AgNP-stresses. In the pre-illuminated condition, oxidative damage was obvious, as indicated by the higher malondialdehyde (MDA) content and an up-regulation of superoxide dismutase (SOD) activity. The maximum increases of MDA content and SOD activity were 1.14 and 2.52 times the respective controls when exposed to 10 mg/L AgNPs. In contrast, in the post-illuminated condition, the alterations in photosynthetic pigment and soluble proteins content were more significant than the alterations in oxidative stress. The contents of chlorophyll a, carotenoids and soluble protein decreased to 77.7%, 66.2% and 72.9% of the controls after treatment with the highest concentration of AgNPs (10 mg/L). Based on the different physiological responses, we speculated that in the pre-illuminated condition, oxidative stress was responsible for the decline in the oxygen evolution rate, while in the post-illuminated condition, the decrease in the Hill reaction activity could be attributed to the blocking of electron transfer and an insufficient proton supply. Our findings demonstrate that environmental factors regulate the

  19. Known and novel terpenes from Buddleja globosa displaying selective antifungal activity against dermatophytes.

    Science.gov (United States)

    Mensah, A Y; Houghton, P J; Bloomfield, S; Vlietinck, A; Vanden Berghe, D

    2000-09-01

    Lipophilic extracts of the stembark of Buddleja globosa were found to have antifungal activity at 125 microg/mL against three dermatophytic fungal species but had no activity at 1000 microg/mL against four other fungal species or two yeast species. Bioassay-guided fractionation of Si gel column eluates using the sensitive fungal species resulted in active fractions from which were isolated five compounds that were characterized by spectroscopic methods as one novel and four known compounds. The known compounds were the diterpene buddlejone (1), the bisditerpene maytenone, and the two sesquiterpenes buddledin A and buddledin B, while the novel compound was characterized as the diterpene deoxybuddlejone (2). The minimum inhibitory concentration of all the compounds was determined against all the microorganisms under test, and buddledins A and B were shown to exhibit the greatest antifungal activity, with values of 43 microM and 51 microM, respectively, against the sensitive fungi Trichophyton rubrum, Tricophyton interdigitale, and Epidermophyton floccosum.

  20. Bacteroidales ectosymbionts of gut flagellates shape the nitrogen-fixing community in dry-wood termites

    Science.gov (United States)

    Desai, Mahesh S; Brune, Andreas

    2012-01-01

    Although it is well documented that the lack of nitrogen in the diet of wood-feeding termites is compensated by the nitrogen-fixing capacity of their gut microbiota, the bacteria responsible for this activity are largely unknown. Here, we analyzed the diversity and expression of nitrogenase genes (homologs of nifH) in four species of dry-wood termites (Kalotermitidae), which thrive on a particularly nitrogen-poor resource. Although each species harbored a highly diverse suite of termite-specific homologs in their microliter-sized hindgut, only a core set related to nifH genes of Treponema and Azoarcus spp., ‘Azobacteroides pseudotrichonymphae', the first member of the Bacteroidales identified as a diazotroph, and termite-gut-specific anfH genes of hitherto unknown origin were preferentially expressed. Transcription patterns corroborated that the populations of active diazotrophs differ fundamentally between termite genera. Capillary-picked suspensions of the flagellates Devescovina arta and Snyderella tabogae revealed that their bacterial ectosymbionts each possess two paralogs of nifH, which apparently have been acquired consecutively during evolution of Bacteroidales, but only one of them (anfH) is actively expressed. Transcription patterns correlated neither with the molybdenum content of the diet nor with intestinal hydrogen concentrations, measured with microsensors. We propose that the nitrogen-fixing community in different dry-wood termites is shaped by the symbionts of their specific flagellate populations. Our findings suggest that the diazotrophic nature of ‘Armantifilum devescovinae' has an important role in the nitrogen metabolism of dry-wood termites and is the driving force of co-evolution with its flagellate host. PMID:22189498

  1. Growth and flagellation of Vibrio fischeri during initiation of the sepiolid squid light organ symbiosis.

    Science.gov (United States)

    Ruby, E G; Asato, L M

    1993-01-01

    A pure culture of the luminous bacterium Vibrio fischeri is maintained in the light-emitting organ of the sepiolid squid Euprymna scolopes. When the juvenile squid emerges from its egg it is symbiont-free and, because bioluminescence is part of an anti-predatory behavior, therefore must obtain a bacterial inoculum from the surrounding environment. We document here the kinetics of the process by which newly hatched juvenile squids become infected by symbiosis-competent V. fischeri. When placed in seawater containing as few as 240 colony-forming-units (CFU) per ml, the juvenile became detectably bioluminescent within a few hours. Colonization of the nascent light organ was initiated with as few as 1 to 10 bacteria, which rapidly began to grow at an exponential rate until they reached a population size of approximately 10(5) cells by 12 h after the initial infection. Subsequently, the number of bacteria in the established symbiosis was maintained essentially constant by a combination of both a > 20-fold reduction in bacterial growth rate, and an expulsion of excess bacteria into the surrounding seawater. While V. fischeri cells are normally flagellated and motile, these bacteria did not elaborate these appendages once the symbiosis was established; however, they quickly began to synthesize flagella when they were removed from the light organ environment. Thus, two important biological characteristics, growth rate and flagellation, were modulated during establishment of the association, perhaps as part of a coordinated series of symbiotic responses.

  2. Effect of Exogenous Application of Hydrogen Peroxide on Drought Tolerance of Glob Amaranth (Gomphrena globosa L.

    Directory of Open Access Journals (Sweden)

    M Goldani

    2012-12-01

    Full Text Available Drought is one of the important environmental stresses that reduce the crop growth. Oxidative stress is a secondary stress due to drought and other abiotic stresses. In order to study the effect of exogenous application of hydrogen peroxide on drought tolerance of glob amaranth (Gomphrena globosa L., an experiment was conducted in greenhouse conditions. This study was designed as factorial based on completely randomized design with 3 replications. Different concentrations of hydrogen peroxide (0, 2.5 and 5 mM and three levels of irrigation intervals (after 4, 7 and 10 days were treated in this study. The results showed that foliar application of hydrogen peroxide can improve shoot and root dry weight and alleviate adverse effects of drought stress. With increasing drought stress stomatal conductance, flower number, total chlorophyll and root volume decreased significantly. So that the lowest of these characterestics was in the irrigation after 10 days. Interaction effects of drought and hydrogen peroxide in shoot dry weight was significantly different in 5% level and in electrolyte leakage, relative water content, free proline and total root length was significantly different in 1% level. In control (4 day irrigation interval with increasing hydrogen peroxide of 2.5 mM, shoot dry weight and total root length increased 20% and 91%, respectively. In control, with increasing hydrogen peroxide to 5 mM total chlorophyll was increased 30.8% compared to 0 mM hydrogen peroxide application (control. The final result showed that foliar application of hydrogen peroxide decreased the adverse effects of drought stress.

  3. Effects of temperature, salinity, and irradiance on the growth of harmful algal bloom species Phaeocystis globosa Scherffel (Prymnesiophyceae) isolated from the South China Sea

    Science.gov (United States)

    Xu, Ning; Huang, Bozhu; Hu, Zhangxi; Tang, Yingzhong; Duan, Shunshan; Zhang, Chengwu

    2017-05-01

    Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal waters that facilitate its rapid expansion, the effects of temperature, salinity and irradiance on the growth of P. globosa from the South China Sea were examined in the laboratory. The saturating irradiance for the growth of P. globosa ( I s) was 60 μmol/(m2•s), which was lower than those of other harmful algal species (70-114 μmol/(m2•s)). A moderate growth rate of 0.22/d was observed at 2 μmol/(m2•s) (the minimum irradiance in the experiment), and photo-inhibition did not occur at 230 μmol/(m2•s) (the maximum irradiance in the experiment). Exposed to 42 different combinations of temperatures (10-31°C) and salinities (10-40) under saturating irradiance, P. globosa exhibited its maximum specific growth rate of 0.80/d at the combinations of 24°C and 35, and 27°C and 40. The optimum growth rates (>0.80/d) were observed at temperatures ranging from 24 to 27°C and salinities from 35 to 40. While P. globosa was able to grow well at temperatures from 20°C to 31°C and salinities from 20 to 40, it could not grow at temperatures lower than 15°C or salinities lower than 15. Factorial analysis revealed that temperature and salinity has similar influences on the growth of this species. This strain of P. globosa not only prefers higher temperatures and higher salinity, but also possesses a flexible nutrient competing strategy, adapted to lower irradiance. Therefore, the P. globosa population from South China Sea should belong to a new ecotype. There is also a potentially high risk of blooms developing in this area throughout the year.

  4. Combined effects of the herbicide terbuthylazine and temperature on different flagellates from the Northern Adriatic Sea.

    Science.gov (United States)

    Fiori, Emanuela; Mazzotti, Matilde; Guerrini, Franca; Pistocchi, Rossella

    2013-03-15

    The triazinic herbicide terbuthylazine (TBA) is becoming an emergent contaminant in Italian rivers and in coastal and groundwater. A preliminary analysis of the sensitivity of marine flagellates to TBA was performed by monitoring the photosynthetic efficiency of nine species (belonging to the Dinophyceae or Raphidophyceae class) isolated from the Adriatic Sea. Different sensitivity levels for each flagellate were observed and the most sensitive microalgae, based on PSII inhibition, were: Gonyaulax spinifera>Fibrocapsa japonica>Lingulodinium polyedrum while the most resistant were two species belonging to the Prorocentrum genus. Then the response of two microalgae to drivers, such as temperature and terbuthylazine, applied in combination was also investigated. Two potentially toxic flagellates, Prorocentrum minimum and G. spinifera, were exposed, under different temperature conditions (15, 20 and 25°C), to TBA concentrations that did not completely affect PSII. For both flagellates, effects of TBA on algal growth, measured through cell density and carbon analysis, as well as on the photosynthetic activity are reported. All parameters analyzed showed a negative effect of TBA from the exponential phase. TBA effect on algal growth was significantly enhanced at the optimal temperature conditions (20 and 25°C), while no difference between control and herbicide treatments were detected for G. spinifera grown at 15°C, which represented a stress condition for this species. The maximum inhibition of photosynthetic efficiency was found at 20°C for both organisms. Both flagellates increased cell carbon and nitrogen content in herbicide treatments compared to the control, except G. spinifera grown at 15°C. Chlorophyll-a production was increased only in G. spinifera exposed to 5 μg L(-1) of TBA and the effect was enhanced with the increase of temperature. Herbicide-induced variations in cellular components determined changes in cellular carbon:nitrogen (C:N) and

  5. A common soil flagellate (Cercomonas sp.) grows slowly when feeding on the bacterium Rhodococcus fascians in isolation, but does not discriminate against it in a mixed culture with Sphingopyxis witflariensis

    DEFF Research Database (Denmark)

    Lekfeldt, Jonas D S; Rønn, Regin

    2008-01-01

    Flagellates are very important predators on bacteria in soil. Because of their high growth rates, flagellate populations respond rapidly to changes in bacterial numbers. Previous results indicate that actinobacteria are generally less suitable than proteobacteria as food for flagellates. In this ......Flagellates are very important predators on bacteria in soil. Because of their high growth rates, flagellate populations respond rapidly to changes in bacterial numbers. Previous results indicate that actinobacteria are generally less suitable than proteobacteria as food for flagellates....... In this study, we investigated the growth of the flagellate Cercomonas sp. (ATCC 50334) on each of the two bacteria Sphingopyxis witflariensis (Alphaproteobacteria) and Rhodococcus fascians (actinobacteria) separately and in combination. The growth rate of the flagellate was lower and the lag phase was longer...

  6. Development of Phaeocystis globosa blooms in the upwelling waters of the South Central coast of Viet Nam

    Science.gov (United States)

    Hai, Doan-Nhu; Lam, Nguyen-Ngoc; Dippner, Joachim W.

    2010-11-01

    Blooms of haptophyte algae in the south central coastal waters of Viet Nam often occur in association with upwelling phenomenon during the southwest (SW) monsoon. Depending on the magnitude of the blooms, damage to aquaculture farms may occur. Based on two years of data on biology, oceanography, and marine chemistry, the present study suggests a conceptual model of the growth of the haptophyte Phaeocystis globosa. At the beginning of the bloom, low temperature and abundant nutrient supply, especially nitrate from rain and upwelling, favour bloom development. Diatoms utilize available nitrate and phosphate; subsequently, higher ammonium concentration allows P. globosa to grow faster than the diatoms. At the end of the Phaeocystis bloom, free cells may become available as food for a heterotrophic dinoflagellate species, Noctiluca scintillans. During and after the phytoplankton bloom, remineralization by bacteria reduces dissolved oxygen to a very low concentration at depth, and favors growth of nitrate-reducing bacteria.A Lagrangian Harmful Algal Bloom (HAB) model, driven by a circulation model of the area, realistically simulates the transport of microalgae in surface waters during strong and weak SW monsoon periods, suggesting that it may be a good tool for early warning of HABs in Vietnamese coastal waters.

  7. A population of giant tailed virus-like particles associated with heterotrophic flagellates in a lake-type reservoir

    Czech Academy of Sciences Publication Activity Database

    Weinbauer, M.G.; Dolan, J. R.; Šimek, Karel

    2015-01-01

    Roč. 76, č. 2 (2015), s. 111-116 ISSN 0948-3055 R&D Projects: GA ČR(CZ) GA13-00243S Institutional support: RVO:60077344 Keywords : viral infection * virus induced mortality * burst size * heterotrophic flagellates Subject RIV: EE - Microbiology, Virology Impact factor: 2.109, year: 2015

  8. Changes in the flagellar bundling time account for variations in swimming behavior of flagellated bacteria in viscous media

    NARCIS (Netherlands)

    Qu, Zijie; Temel, Fatma Zeynep; Henderikx, Rene; Breuer, Kenneth S.

    2018-01-01

    Although the motility of the flagellated bacteria, Escherichia coli, has been widely studied, the effect of viscosity on swimming speed remains controversial. The swimming mode of wild-type E. coli is often idealized as a run-and-tumble sequence in which periods of swimming at a constant speed are

  9. Interaction between Food-borne Pathogens (Campylobacter jejuni, Salmonella Typhimurium and Listeria monocytogenes) and a Common Soil Flagellate (Cercomonas sp.)

    DEFF Research Database (Denmark)

    Bui, Thanh Xuan; Wolff, Anders; Madsen, Mogens

    2012-01-01

    Free-living protozoa may harbor, protect, and disperse bacteria, including those ingested and passed in viable form in feces. The flagellates are very important predators on bacteria in soil, but their role in the survival of food-borne pathogens associated with fruits and vegetables is not well...

  10. Construction and analysis of the cDNA subtraction library of yeast and mycelial phases of Sporothrix globosa isolated in China: identification of differentially expressed genes*

    Science.gov (United States)

    Hu, Qing-bi; He, Yu; Zhou, Xun

    2015-01-01

    Species included in the Sporothrix schenckii complex are temperature-dependent with dimorphic growth and cause sporotrichosis that is characterized by chronic and fatal lymphocutaneous lesions. The putative species included in the Sporothrix complex are S. brasiliensis, S. globosa, S. mexicana, S. pallida, S. schenckii, and S. lurei. S. globosa is the causal agent of sporotrichosis in China, and its pathogenicity appears to be closely related to the dimorphic transition, i.e. from the mycelial to the yeast phase, it adapts to changing environmental conditions. To determine the molecular mechanisms of the switching process that mediates the dimorphic transition of S. globosa, suppression subtractive hybridization (SSH) was used to prepare a complementary DNA (cDNA) subtraction library from the yeast and mycelial phases. Bioinformatics analysis was performed to profile the relationship between differently expressed genes and the dimorphic transition. Two genes that were expressed at higher levels by the yeast form were selected, and their differential expression levels were verified using a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). It is believed that these differently expressed genes are involved in the pathogenesis of S. globosa infection in China. PMID:26642182

  11. Heavy metal toxicity and bioavailability of dissolved nutrients to a bacterivorous flagellate are linked to suspended particle physical properties

    International Nuclear Information System (INIS)

    Boenigk, Jens; Wiedlroither, Anneliese; Pfandl, Karin

    2005-01-01

    Many dissolved substances attach easily to sediment particles. In the presence of suspended sediments bioavailability of dissolved substances is therefore, usually reduced and clays are even applied to 'wash' natural waters upon pollution. In organisms which feed on food organisms in the size range of these suspended sediment particles, however, bioavailability of such substances may even increase. For microorganisms the interaction with dissolved substances and suspended sediment particles so far has hardly been investigated. We specifically tested: (1) the importance of suspended particles as an uptake route for dissolved substances; and (2) the significance of particle surface properties, i.e. surface load and mineralogy. As a model system we used an axenically cultured strain of a widespread and often abundant flagellate ('Spumella-like' flagellate strain JBM10). We tested the toxicity of cadmium (II) and mercury (II) as well as availability of dissolved organic matter (DOM) in the absence as well as in the presence of different natural clays, i.e. a kaolinite, a montmorillonite, and a mixed clay, and of artificial silicate particles of different surface charge. When applied separately the presence of the heavy metals cadmium and mercury as well as of suspended particles negatively affected the investigated flagellate but nutritive organics supported growth of the investigated flagellate. Toxic stress response comprises behavioral changes including enhanced swimming activity and stress egestion of ingested particles and was generally similar for a variety of different flagellate species. In combination with suspended particles, the respective effect of trace metals and nutritive substances decreased. Regarding the particle quality, cadmium toxicity increased with increasingly negative surface charge, i.e. increasing surface density of silanol groups (Pearson's product moment, P = 0.005). For mercury particle mineralogy still had a significant effect (P < 0

  12. Symbiotic flagellate protists as cryptic drivers of adaptation and invasiveness of the subterranean termite Reticulitermes grassei Clément.

    Science.gov (United States)

    Duarte, Sónia; Nobre, Tânia; Borges, Paulo A V; Nunes, Lina

    2018-06-01

    Changes in flagellate protist communities of subterranean termite Reticulitermes grassei across different locations were evaluated following four predictions: (i) Rural endemic (Portugal mainland) termite populations will exhibit high diversity of symbionts; (ii) invasive urban populations (Horta city, Faial island, Azores), on the contrary, will exhibit lower diversity of symbionts, showing high similarity of symbiont assemblages through environmental filtering; (iii) recent historical colonization of isolated regions-as the case of islands-will imply a loss of symbiont diversity; and (iv) island isolation will trigger a change in colony breeding structure toward a less aggressive behavior. Symbiont flagellate protist communities were morphologically identified, and species richness and relative abundances, as well as biodiversity indices, were used to compare symbiotic communities in colonies from urban and rural environments and between island invasive and mainland endemic populations. To evaluate prediction on the impact of isolation (iv), aggression tests were performed among termites comprising island invasive and mainland endemic populations. A core group of flagellates and secondary facultative symbionts was identified. Termites from rural environments showed, in the majority of observed colonies, more diverse and abundant protist communities, probably confirming prediction (i). Corroborating prediction (ii), the two least diverse communities belong to termites captured inside urban areas. The Azorean invasive termite colonies had more diverse protist communities than expected and prediction (iii) which was not verified within this study. Termites from mainland populations showed a high level of aggressiveness between neighboring colonies, in contrast to the invasive colonies from Horta city, which were not aggressive to neighbors according to prediction (iv). The symbiotic flagellate community of R. grassei showed the ability to change in a way that might

  13. Transfer of seston lipids during a flagellate bloom from the surface to the benthic community in the Weddell Sea

    Directory of Open Access Journals (Sweden)

    Sergio Rossi

    2013-09-01

    Full Text Available Total lipid and fatty acid concentrations were studied in a late spring-early summer flagellate-dominated bloom in the Weddell Sea. These indicators were considered a good tool for assessing the quality of organic matter settling from surface to deep-water layers (epibenthic water layers. The results showed different patterns between the early (11-15 December 2003 and the late sampling period (18-27 December 2003 at all studied depths (5 m, 50 m and near-bottom water layers. Low phytoplankton biomass (mainly flagellates in the first half of the study corresponded to low total lipid and fatty acid concentrations. In the second sampling period a spring bloom (mainly flagellates and diatoms was detected, increasing the total lipid and fatty acid concentrations in the water column. The amount of settling organic matter from surface waters to the near-bottom water layers was high, especially in the late sampling period. Trophic markers showed evidence of a sink of available organic matter rich in quality and quantity, especially in terms of polyunsaturated fatty acids, for benthic organisms from surface layers to bottom layers in only a few days. The importance of studying short-time cycles in order to detect organic matter availability for benthic biota in view of the pulse-like dynamics of primary production in Antarctic waters is discussed.

  14. Morphological and molecular identification of Tetratrichomonas flagellates from the giant anteater (Myrmecophaga tridactyla).

    Science.gov (United States)

    Ibañez-Escribano, A; Nogal-Ruiz, J J; Delclaux, M; Martinez-Nevado, E; Ponce-Gordo, F

    2013-08-01

    A tetratrichomonad flagellate found in the diarrhoeic faeces of a 5 years-old male giant anteater (Myrmecophaga tridactyla) was characterised by morphological and genetic analysis. This protozoan presents four anterior flagella of unequal length and a recurrent flagellum attached to the undulating membrane without a free end portion, and a broad axostyle projection. Numerous vacuoles of different sizes containing bacteria and digestion products were found. The complete sequence of the DNA coding for the 16S rRNA-ITS1-5.8S rRNA-ITS2 region was also obtained in order to compare this isolate with other tetratrichomonad species. The sequence obtained was identical to others previously obtained by other researchers from bovines and turtles (Geochelone sp.). It is not easily explainable how the same organism could be found in such different hosts and locations; however these results indicate that some tetratrichomonad species could have a wide host range and could survive in a wide range of environmental conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Live-cell super-resolution imaging of intrinsically fast moving flagellates

    International Nuclear Information System (INIS)

    Glogger, M; Subota, I; Spindler, M-C; Engstler, M; Fenz, S F; Stichler, S; Bertlein, S; Teßmar, J; Groll, J

    2017-01-01

    Recent developments in super-resolution microscopy make it possible to resolve structures in biological cells at a spatial resolution of a few nm and observe dynamical processes with a temporal resolution of ms to μ s. However, the optimal structural resolution requires repeated illumination cycles and is thus limited to chemically fixed cells. For live cell applications substantial improvement over classical Abbe-limited imaging can already be obtained in adherent or slow moving cells. Nonetheless, a large group of cells are fast moving and thus could not yet be addressed with live cell super-resolution microscopy. These include flagellate pathogens like African trypanosomes, the causative agents of sleeping sickness in humans and nagana in livestock. Here, we present an embedding method based on a in situ forming cytocompatible UV-crosslinked hydrogel. The fast cross-linking hydrogel immobilizes trypanosomes efficiently to allow microscopy on the nanoscale. We characterized both the trypanosomes and the hydrogel with respect to their autofluorescence properties and found them suitable for single-molecule fluorescence microscopy (SMFM). As a proof of principle, SMFM was applied to super-resolve a structure inside the living trypanosome. We present an image of a flagellar axoneme component recorded by using the intrinsic blinking behavior of eYFP. (paper)

  16. Seasonal variability in irradiance affects herbicide toxicity to the marine flagellate Dunaliella tertiolecta

    Directory of Open Access Journals (Sweden)

    Sascha eSjollema

    2014-06-01

    Full Text Available Photosynthetically Active Radiation (PAR and Ultraviolet Radiation (UVR of the solar spectrum affect microalgae directly and modify the toxicity of phytotoxic compounds present in water. As a consequence seasonal variable PAR and UVR levels are likely to modulate the toxic pressure of contaminants in the field. Therefore the present study aimed to determine the toxicity of two model contaminants, the herbicides diuron and Irgarol®1051, under simulated irradiance conditions mimicking different seasons. Irradiance conditions of spring and autumn were simulated with a set of Light Emitting Diodes (LEDs. Toxicity of both herbicides was measured individually and in a mixture by determining the inhibition of photosystem II efficiency (ΦPSII of the marine flagellate Dunaliella teriolecta using Pulse Amplitude Modulation (PAM fluorometry. Toxicity of the single herbicides was higher under simulated spring irradiance than under autumn irradiance and this effect was also observed for mixtures of the herbicides. This irradiance dependent toxicity indicates that herbicide toxicity in the field is seasonally variable. Consequently toxicity tests under standard light conditions may overestimate or underestimate the toxic effect of phytotoxic compounds.

  17. Effects of solar and artificial UV irradiation on motility and phototaxis in the flagellate, Euglena gracilis

    International Nuclear Information System (INIS)

    Haeder, D.-P.

    1986-01-01

    The effect of solar irradiation on the percentage of motile cells, their average speed and their phototactic orientation to white actinic light was studied in the flagellate, Euglena gracilis. Unfiltered solar radiation in midsummer during mid-day at a location near Lisboa, Portugal, was found to impair motility within 2 h. This effect is exclusively due to the UV-B component of the radiation and not due to UV-A, visible light or a temperature increase. Likewise, phototactic orientation was drastically impaired. Reduction of the solar UV-B irradiation by insertion of an ozone-flooded plexiglass cuvette partially reduced the inhibition and covering the cuvettes with glass prevented any decrease in motility and photoorientation. Similar results were found with artificial irradiation (Xe lamps). After inoculation, the motility of the population follows an optimum curve (optimum at 8 days). Also, the UV-B effect on motility was smallest after about one week and increased for younger and older cultures. (author)

  18. Identification criteria of the rare multi-flagellate Lophomonas blattarum: comparison of different staining techniques.

    Science.gov (United States)

    Alam-Eldin, Yosra Hussein; Abdulaziz, Amany Mamdouh

    2015-09-01

    Bronchopulmonary lophomoniasis (BPL) is an emerging disease of potential importance. BPL is presented by non-specific clinical picture and is usually accompanied by immunosuppression. Culture of Lophomonas blattarum is difficult and its molecular diagnosis has not yet been developed. Therefore, microscopic examination of respiratory samples, e.g., bronchoalveolar lavage (BAL) or sputum, is the mainstay of BPL diagnosis. Creola bodies and ciliocytophthoria are two forms of bronchial cells which occur in chest diseases with non-specific clinical picture like that of BPL. Both forms could be misrecognized as multi-flagellates because of their motile cilia in the wet mounts and due to shape variability of L. blattarum in stained smears. The aim of the study is to compare different staining techniques for visualizing L. blattarum to improve the recognition and diagnosis of BPL, to distinguish respiratory epithelial cells from L. blattarum and to decide which stain is recommended in suspected cases of BPL. BAL samples from patients which contain L. blattarum, creola bodies, and ciliocytophthoria were collected then wet mounts were examined. The BAL samples were also stained by Papanicolaou (PAP), Giemsa, hematoxylin and eosin (H & E), trichrome, Gram, and Diff-Quik (DQ) stains. The different staining techniques were compared regarding the stain quality. In wet mounts, the ciliary movement was coordinate and synchronous while the flagellar movement was wavy and leaded to active swimming of L. blattarum. In stained slides, bronchial cells were characterized by the presence of basal nucleus and the terminal bar from which the cilia arise. Trichrome was the best stain in demonstration of cellular details of L. blattarum. H & E, PAP, and Giemsa stains showed good quality of stains. Gram and DQ stains showed only pale hues of L. blattarum. We recommended adding Wheatley's trichrome staining to the differential diagnosis workup of cases of non-specific chest infections

  19. Upper Arctic Ocean water masses harbor distinct communities of heterotrophic flagellates

    Directory of Open Access Journals (Sweden)

    A. Monier

    2013-06-01

    Full Text Available The ubiquity of heterotrophic flagellates (HFL in marine waters has been recognized for several decades, but the phylogenetic diversity of these small (ca. 0.8–20 μm cell diameter, mostly phagotrophic protists in the upper pelagic zone of the ocean is underappreciated. Community composition of microbes, including HFL, is the result of past and current environmental selection, and different taxa may be indicative of food webs that cycle carbon and energy very differently. While all oceanic water columns can be density stratified due to the temperature and salinity characteristics of different water masses, the Arctic Ocean is particularly well stratified, with nutrients often limiting in surface waters and most photosynthetic biomass confined to a subsurface chlorophyll maximum layer, where light and nutrients are both available. This physically well-characterized system provided an opportunity to explore the community diversity of HFL from different water masses within the water column. We used high-throughput DNA sequencing techniques as a rapid means of surveying the diversity of HFL communities in the southern Beaufort Sea (Canada, targeting the surface, the subsurface chlorophyll maximum layer (SCM and just below the SCM. In addition to identifying major clades and their distribution, we explored the micro-diversity within the globally significant but uncultivated clade of marine stramenopiles (MAST-1 to examine the possibility of niche differentiation within the stratified water column. Our results strongly suggested that HFL community composition was determined by water mass rather than geographical location across the Beaufort Sea. Future work should focus on the biogeochemical and ecological repercussions of different HFL communities in the face of climate-driven changes to the physical structure of the Arctic Ocean.

  20. Live-cell super-resolution imaging of intrinsically fast moving flagellates

    Science.gov (United States)

    Glogger, M.; Stichler, S.; Subota, I.; Bertlein, S.; Spindler, M.-C.; Teßmar, J.; Groll, J.; Engstler, M.; Fenz, S. F.

    2017-02-01

    Recent developments in super-resolution microscopy make it possible to resolve structures in biological cells at a spatial resolution of a few nm and observe dynamical processes with a temporal resolution of ms to μs. However, the optimal structural resolution requires repeated illumination cycles and is thus limited to chemically fixed cells. For live cell applications substantial improvement over classical Abbe-limited imaging can already be obtained in adherent or slow moving cells. Nonetheless, a large group of cells are fast moving and thus could not yet be addressed with live cell super-resolution microscopy. These include flagellate pathogens like African trypanosomes, the causative agents of sleeping sickness in humans and nagana in livestock. Here, we present an embedding method based on a in situ forming cytocompatible UV-crosslinked hydrogel. The fast cross-linking hydrogel immobilizes trypanosomes efficiently to allow microscopy on the nanoscale. We characterized both the trypanosomes and the hydrogel with respect to their autofluorescence properties and found them suitable for single-molecule fluorescence microscopy (SMFM). As a proof of principle, SMFM was applied to super-resolve a structure inside the living trypanosome. We present an image of a flagellar axoneme component recorded by using the intrinsic blinking behavior of eYFP. , which features invited work from the best early-career researchers working within the scope of J Phys D. This project is part of the Journal of Physics series’ 50th anniversary celebrations in 2017. Susanne Fenz was selected by the Editorial Board of J Phys D as an Emerging Talent/Leader.

  1. The structure of the mitotic spindle and nucleolus during mitosis in the amebo-flagellate Naegleria.

    Science.gov (United States)

    Walsh, Charles J

    2012-01-01

    Mitosis in the amebo-flagellate Naegleria pringsheimi is acentrosomal and closed (the nuclear membrane does not break down). The large central nucleolus, which occupies about 20% of the nuclear volume, persists throughout the cell cycle. At mitosis, the nucleolus divides and moves to the poles in association with the chromosomes. The structure of the mitotic spindle and its relationship to the nucleolus are unknown. To identify the origin and structure of the mitotic spindle, its relationship to the nucleolus and to further understand the influence of persistent nucleoli on cellular division in acentriolar organisms like Naegleria, three-dimensional reconstructions of the mitotic spindle and nucleolus were carried out using confocal microscopy. Monoclonal antibodies against three different nucleolar regions and α-tubulin were used to image the nucleolus and mitotic spindle. Microtubules were restricted to the nucleolus beginning with the earliest prophase spindle microtubules. Early spindle microtubules were seen as short rods on the surface of the nucleolus. Elongation of the spindle microtubules resulted in a rough cage of microtubules surrounding the nucleolus. At metaphase, the mitotic spindle formed a broad band completely embedded within the nucleolus. The nucleolus separated into two discreet masses connected by a dense band of microtubules as the spindle elongated. At telophase, the distal ends of the mitotic spindle were still completely embedded within the daughter nucleoli. Pixel by pixel comparison of tubulin and nucleolar protein fluorescence showed 70% or more of tubulin co-localized with nucleolar proteins by early prophase. These observations suggest a model in which specific nucleolar binding sites for microtubules allow mitotic spindle formation and attachment. The fact that a significant mass of nucleolar material precedes the chromosomes as the mitotic spindle elongates suggests that spindle elongation drives nucleolar division.

  2. Survival of marine heterotrophic flagellates isolated from the surface and the deep sea at high hydrostatic pressure: Literature review and own experiments

    Science.gov (United States)

    Živaljić, Suzana; Schoenle, Alexandra; Nitsche, Frank; Hohlfeld, Manon; Piechocki, Julia; Reif, Farina; Shumo, Marwa; Weiss, Alexandra; Werner, Jennifer; Witt, Madeleine; Voss, Janine; Arndt, Hartmut

    2018-02-01

    Although the abyssal seafloor represents the most common benthic environment on Earth, eukaryotic microbial life at abyssal depths is still an uncharted territory. This is in striking contrast to their potential importance regarding the material flux and bacteria consumption in the deep sea. Flagellate genotypes determined from sedimentary DNA deep-sea samples might originate from vital deep-sea populations or from cysts of organisms sedimented down from surface waters. The latter one may have never been active under deep-sea conditions. We wanted to analyze the principal ability of cultivable heterotrophic flagellates of different phylogenetic groups (choanoflagellates, ancyromonads, euglenids, kinetoplastids, bicosoecids, chrysomonads, and cercozoans) to survive exposure to high hydrostatic pressure (up to 670 bar). We summarized our own studies and the few available data from literature on pressure tolerances of flagellates isolated from different marine habitats. Our results demonstrated that many different flagellate species isolated from the surface waters and deep-sea sediments survived drastic changes in hydrostatic pressure. Barophilic behavior was also recorded for several species isolated from the deep sea indicating their possible genetic adaptation to high pressures. This is in accordance with records of heterotrophic flagellates present in environmental DNA surveys based on clone libraries established for deep-sea environments.

  3. EST analysis of the scaly green flagellate Mesostigma viride (Streptophyta: Implications for the evolution of green plants (Viridiplantae

    Directory of Open Access Journals (Sweden)

    Melkonian Michael

    2006-02-01

    Full Text Available Abstract Background The Viridiplantae (land plants and green algae consist of two monophyletic lineages, the Chlorophyta and the Streptophyta. The Streptophyta include all embryophytes and a small but diverse group of freshwater algae traditionally known as the Charophyceae (e.g. Charales, Coleochaete and the Zygnematales. The only flagellate currently included in the Streptophyta is Mesostigma viride Lauterborn. To gain insight into the genome evolution in streptophytes, we have sequenced 10,395 ESTs from Mesostigma representing 3,300 independent contigs and compared the ESTs of Mesostigma with available plant genomes (Arabidopsis, Oryza, Chlamydomonas, with ESTs from the bryophyte Physcomitrella, the genome of the rhodophyte Cyanidioschyzon, the ESTs from the rhodophyte Porphyra, and the genome of the diatom Thalassiosira. Results The number of expressed genes shared by Mesostigma with the embryophytes (90.3 % of the expressed genes showing similarity to known proteins is higher than with Chlamydomonas (76.1 %. In general, cytosolic metabolic pathways, and proteins involved in vesicular transport, transcription, regulation, DNA-structure and replication, cell cycle control, and RNA-metabolism are more conserved between Mesostigma and the embryophytes than between Mesostigma and Chlamydomonas. However, plastidic and mitochondrial metabolic pathways, cytoskeletal proteins and proteins involved in protein folding are more conserved between Mesostigma and Chlamydomonas than between Mesostigma and the embryophytes. Conclusion Our EST-analysis of Mesostigma supports the notion that this organism should be a suitable unicellular model for the last flagellate common ancestor of the streptophytes. Mesostigma shares more genes with the embryophytes than with the chlorophyte Chlamydomonas reinhardtii, although both organisms are flagellate unicells. Thus, it seems likely that several major physiological changes (e.g. in the regulation of photosynthesis

  4. Clinical and pathological observations on natural infections of cryptosporidiosis and flagellate protozoa in leopard geckos (Eublepharis macularius).

    Science.gov (United States)

    Taylor, M A; Geach, M R; Cooley, W A

    1999-12-11

    A group of adult leopard geckos (Eublepharis macularius) which had been losing weight for several months were found to be infected with Cryptosporidium species. Histological and electron microscopical investigations on the intestines of five of the lizards revealed the presence of large numbers of the developmental stages of Cryptosporidium species attached to the mucosal surface of the lower intestine, and large numbers of flagellate protozoa, suspected to be predominantly Trichomonas species, in the gut lumen. The clinical signs were attributed to the presence of one or both types of parasites.

  5. Development and application of a most probable number-PCR assay to quantify flagellate populations in soil samples

    DEFF Research Database (Denmark)

    Fredslund, Line; Ekelund, Flemming; Jacobsen, Carsten Suhr

    2001-01-01

    This paper reports on the first successful molecular detection and quantification of soil protozoa. Quantification of heterotrophic flagellates and naked amoebae in soil has traditionally relied on dilution culturing techniques, followed by most-probable-number (MPN) calculations. Such methods...... are biased by differences in the culturability of soil protozoa and are unable to quantify specific taxonomic groups, and the results are highly dependent on the choice of media and the skills of the microscopists. Successful detection of protozoa in soil by DNA techniques requires (i) the development...

  6. Contrasting bee pollination in two co-occurring distylic species of Cordia (Cordiaceae, Boraginales) in the Brazilian semi-arid Caatinga: generalist in C. globosa vs. specialist in C. leucocephala.

    Science.gov (United States)

    Machado, Isabel C; Lopes, Ariadna V; Sazima, Marlies

    2010-12-01

    In this study we compare the reproductive biology of Cordia globosa and C. leucocephala (Cordiaceae, Boraginales; formerly referred to Boraginaceae) to understand the functioning of the floral morphs and the relations with their effective pollinators. The species are synchronopatric, distylic, and self-incompatible. Though they share melittophilous traits, the main visitor and pollinator of C. globosa was the generalist and exotic bee Apis mellifera, while the only one of C. leucocephala was the oligoletic bee Ceblurgus longipalpis. These two latter species are restricted to the Caatinga of NE Brazil, contrasting with the wide distribution of Cordia globosa. While the fruit-set for C. globosa was high, independently if the pollen donor/stigma receptor was a pin (long-styled) or thrum (short-styled) individual, in C. leucocephala the fruit-set was low and occurred only when a thrum individual was the pollen donor. This raises the possibility of this species moving towards dioecy. The high natural fruit-set of C. globosa confirms the generalist bee as its effective pollinator. The low fruit-set after manual crosses in C. leucocephala may be due to low pollen viability. Additionally, the low natural fruit-set (two times lower than after crosses) may be related with the foraging behavior of the specialist pollinator.

  7. Trypanosoma cruzi alkaline 2-DE: Optimization and application to comparative proteome analysis of flagellate life stages

    Directory of Open Access Journals (Sweden)

    Santana Jaime M

    2008-09-01

    Full Text Available Abstract Background Trypanosoma cruzi, a flagellate protozoan, is the etiological agent of Chagas disease, a chronic illness that causes irreversible damage to heart and digestive tract in humans. Previous 2-DE analyses of T. cruzi proteome have not focused on basic proteins, possibly because of inherent difficulties for optimizing 2-DE in the alkaline pH range. However, T. cruzi wide pH range 2-DE gels have shown few visible spots in the alkaline region, indicating that the parasite either did not have an appreciable amount of alkaline proteins or that these proteins were underrepresented in the 2-DE gels. Results Different IEF conditions using 6–11 pH gradient strips were tested for separation of T. cruzi alkaline proteins. The optimized methodology described here was performed using anodic "paper bridge" sample loading supplemented by increased concentration of DTT and Triton X-100 on Multiphor II (GE Healthcare equipment and an electrode pad embedded in DTT- containing solution near the cathode in order to avoid depletion of reducing agent during IEF. Landmark proteins were identified by peptide mass fingerprinting allowing the production of an epimastigote 2-DE map. Most identified proteins corresponded to metabolic enzymes, especially those related to amino acid metabolism. The optimized 2-DE protocol was applied in combination with the "two-in-one gel" method to verify the relative expression of the identified proteins between samples from epimastigote and trypomastigote life stages. Conclusion High resolution 2-DE gels of T. cruzi life forms were achieved using the optimized methodology and a partial epimastigote alkaline 2-DE map was built. Among 700 protein spots detected, 422 were alkaline with a pI above 7.0. The "two-in-one gel" method simplified the comparative analysis between T. cruzi life stages since it minimized variations in spot migration and silver-stained spot volumes. The comparative data were in agreement with

  8. Swimming Motility Mediates the Formation of Neutrophil Extracellular Traps Induced by Flagellated Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Madison Floyd

    2016-11-01

    Full Text Available Pseudomonas aeruginosa is an opportunistic pathogen causing severe infections often characterized by robust neutrophilic infiltration. Neutrophils provide the first line of defense against P. aeruginosa. Aside from their defense conferred by phagocytic activity, neutrophils also release neutrophil extracellular traps (NETs to immobilize bacteria. Although NET formation is an important antimicrobial process, the details of its mechanism are largely unknown. The identity of the main components of P. aeruginosa responsible for triggering NET formation is unclear. In this study, our focus was to identify the main bacterial factors mediating NET formation and to gain insight into the underlying mechanism. We found that P. aeruginosa in its exponential growth phase promoted strong NET formation in human neutrophils while its NET-inducing ability dramatically decreased at later stages of bacterial growth. We identified the flagellum as the primary component of P. aeruginosa responsible for inducing NET extrusion as flagellum-deficient bacteria remained seriously impaired in triggering NET formation. Purified P. aeruginosa flagellin, the monomeric component of the flagellum, does not stimulate NET formation in human neutrophils. P. aeruginosa-induced NET formation is independent of the flagellum-sensing receptors TLR5 and NLRC4 in both human and mouse neutrophils. Interestingly, we found that flagellar motility, not flagellum binding to neutrophils per se, mediates NET release induced by flagellated bacteria. Immotile, flagellar motor-deficient bacterial strains producing paralyzed flagella did not induce NET formation. Forced contact between immotile P. aeruginosa and neutrophils restored their NET-inducing ability. Both the motAB and motCD genetic loci encoding flagellar motor genes contribute to maximal NET release; however the motCD genes play a more important role. Phagocytosis of P. aeruginosa and superoxide production by neutrophils were also

  9. Formation of large colonies: a defense mechanism of Microcystis aeruginosa under continuous grazing pressure by flagellate Ochromonas sp.

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    Fanxiang Kong

    2012-01-01

    Full Text Available Induced colony formation under grazing pressure has been reported in our previous results. However, the colonies induced in these studies comprised only tens of cells which are far smaller than the naturally occurring colonies. In this work, unicellular Microcystis aeruginosa Kützing were co-cultivated with flagellate Ochromonas sp. for 50 d to investigate colony formation in M. aeruginosa under continuous grazing pressure. Results revealed that colonial M. aeruginosa formed on the 10th d under the grazing pressure of flagellate. These algal colonies resulted from the daughter cells of freshly dividing cells that failed to separate during the reproductive process. The diameters and cell numbers of the colonies increased slowly with time. Under continuous grazing pressure by Ochromonas sp. for 50 d, the diameter of some colonies reached over 180 μm. Analysis showed that the extracellular polysaccharide (EPS content and relative gas vesicle (RGV of each cell increased significantly after colony formation. However, there was no significant difference on the monosaccharide composition between unicellular and colonial M. aeruginosa. The loose aggregation of cells in the floating colonies suggests that a correlation probably exists between cell compactness and colony buoyancy.

  10. Genome of Phaeocystis globosa virus PgV-16T highlights the common ancestry of the largest known DNA viruses infecting eukaryotes

    Science.gov (United States)

    Santini, Sebastien; Jeudy, Sandra; Bartoli, Julia; Poirot, Olivier; Lescot, Magali; Abergel, Chantal; Barbe, Valérie; Wommack, K. Eric; Noordeloos, Anna A. M.; Brussaard, Corina P. D.; Claverie, Jean-Michel

    2013-01-01

    Large dsDNA viruses are involved in the population control of many globally distributed species of eukaryotic phytoplankton and have a prominent role in bloom termination. The genus Phaeocystis (Haptophyta, Prymnesiophyceae) includes several high-biomass-forming phytoplankton species, such as Phaeocystis globosa, the blooms of which occur mostly in the coastal zone of the North Atlantic and the North Sea. Here, we report the 459,984-bp-long genome sequence of P. globosa virus strain PgV-16T, encoding 434 proteins and eight tRNAs and, thus, the largest fully sequenced genome to date among viruses infecting algae. Surprisingly, PgV-16T exhibits no phylogenetic affinity with other viruses infecting microalgae (e.g., phycodnaviruses), including those infecting Emiliania huxleyi, another ubiquitous bloom-forming haptophyte. Rather, PgV-16T belongs to an emerging clade (the Megaviridae) clustering the viruses endowed with the largest known genomes, including Megavirus, Mimivirus (both infecting acanthamoeba), and a virus infecting the marine microflagellate grazer Cafeteria roenbergensis. Seventy-five percent of the best matches of PgV-16T–predicted proteins correspond to two viruses [Organic Lake phycodnavirus (OLPV)1 and OLPV2] from a hypersaline lake in Antarctica (Organic Lake), the hosts of which are unknown. As for OLPVs and other Megaviridae, the PgV-16T sequence data revealed the presence of a virophage-like genome. However, no virophage particle was detected in infected P. globosa cultures. The presence of many genes found only in Megaviridae in its genome and the presence of an associated virophage strongly suggest that PgV-16T shares a common ancestry with the largest known dsDNA viruses, the host range of which already encompasses the earliest diverging branches of domain Eukarya. PMID:23754393

  11. Interactions between the intestinal flagellates Giardia muris and Spironucleus muris and the blood parasites Babesia microti, Plasmodium yoelii and Plasmodium berghei in mice.

    Science.gov (United States)

    Brett, S J; Cox, F E

    1982-08-01

    In mice infected with the intestinal flagellates Giardia muris or Spironucleus muris, together with the blood parasites Babesia microti or Plasmodium yoelii, there is a temporary decrease of flagellate cyst output coincident with the peak of the blood parasite infections, followed by a rapid return to normal levels. This decrease in cyst output is correlated with decreased numbers of trophozoites in the small intestine. The effect on S. muris is more marked than that on G. muris. Neither blood parasites has any effect on the total duration of the flagellate infection and the flagellates do not affect the blood parasites. In mice infected with G. muris or S. muris and P. berghei there is also a decrease in cyst output but this is less apparent than in infections with B. microti or P. yoelii because of the fatal nature of the P. berghei infection. It is suggested that the decrease in cyst output is probably due to changes in the contents of the small intestine or to non-specific immunological factors rather than to specific immunological changes.

  12. Description of Pyramimonas diskoicola sp. nov. and the importance of the flagellate Pyramimonas (Prasinophyceae) in Greenland sea ice during the winter–spring transition

    DEFF Research Database (Denmark)

    Harðardóttir, Sara; Lundholm, Nina; Moestrup, Øjvind

    2014-01-01

    Pyramimonas Schmarda is a genus of unicellular green flagellates, recorded in marine water and sea ice samples. Pyramimonas is within the prey size range of the most important protozoan grazers in Disko Bay, West Greenland, where this study took place. Despite the potential ecological importance...

  13. Flagellated Magnetotactic Bacteria as Controlled MRI-trackable Propulsion and Steering Systems for Medical Nanorobots Operating in the Human Microvasculature.

    Science.gov (United States)

    Martel, Sylvain; Mohammadi, Mahmood; Felfoul, Ouajdi; Lu, Zhao; Pouponneau, Pierre

    2009-04-01

    Although nanorobots may play critical roles for many applications in the human body such as targeting tumoral lesions for therapeutic purposes, miniaturization of the power source with an effective onboard controllable propulsion and steering system have prevented the implementation of such mobile robots. Here, we show that the flagellated nanomotors combined with the nanometer-sized magnetosomes of a single Magnetotactic Bacterium (MTB) can be used as an effective integrated propulsion and steering system for devices such as nanorobots designed for targeting locations only accessible through the smallest capillaries in humans while being visible for tracking and monitoring purposes using modern medical imaging modalities such as Magnetic Resonance Imaging (MRI). Through directional and magnetic field intensities, the displacement speeds, directions, and behaviors of swarms of these bacterial actuators can be controlled from an external computer.

  14. High-speed counter-current chromatography in separation of betacyanins from flowers of red Gomphrena globosa L. cultivars.

    Science.gov (United States)

    Spórna-Kucab, Aneta; Hołda, Ewelina; Wybraniec, Sławomir

    2016-10-15

    Antioxidant and possible chemopreventive properties of betacyanins, natural plant pigments, contribute to a growing interest in their chemistry and separation. Mixtures of betacyanins from fresh red Gomphrena globosa L. cultivar flowers were separated in three highly polar solvent systems by high-speed counter-current chromatography (HSCCC) for a direct comparison of their separation effectiveness. Three samples of crude extract (600mg) were run on semi-preparative scale in solvent system (NH4)2SO4soln - EtOH (2.0:1.0, v/v) (system I) and the modified systems: EtOH - ACN - 1-PrOH - (NH4)2SO4satd.soln - H2O (0.5:0.5:0.5:1.2:1.0, v/v/v/v/v) (system II) and EtOH - ACN - (NH4)2SO4satd.soln - H2O (1.0:0.5:1.2:1.0, v/v/v/v) (system III). The systems were used in the head-to-tail (system I) or tail-to-head (systems II and III) mode. The flow rate of the mobile phase was 2.0ml/min and the column rotation speed was 860rpm. The retention of the stationary phase was 52.0% (system I), 80.2% (systems II) and 82.0% (system III). The betacyanins in the crude extract as well as HSCCC fractions were analyzed by LC-MS/MS. System I was applied for the first time in HSCCC for the separation of betacyanins and was quite effective in separation of amaranthine and 17-decarboxy-amaranthine (αI=1.19) and very effective for 17-decarboxy-amaranthine and betanin (αI=2.20). Modification of system I with acetonitrile (system III) as well as acetonitrile and propanol (system II) increased their separation effectiveness. Systems II-III enable complete separation of 17-decarboxy-amaranthine (KD(II)=2.94,KD(III)=2.42) and betanin (KD(II)=2.46,KD(III)=1.10) as well as betanin and gomphrenin I (KD(II)=1.62, KD(III)=0.74). In addition, separation of amaranthine and 17-decarboxy-amaranthine is the most effective in system II, therefore, this system proved to be the most suitable for the separation of all polar betacyanins. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Contrasting bee pollination in two co-occurring distylic species of Cordia (Cordiaceae, Boraginales in the Brazilian semi-arid Caatinga: generalist in C. globosa vs. specialist in C. leucocephala

    Directory of Open Access Journals (Sweden)

    Isabel C. Machado

    2010-12-01

    Full Text Available In this study we compare the reproductive biology of Cordia globosa and C. leucocephala (Cordiaceae, Boraginales; formerly referred to Boraginaceae to understand the functioning of the floral morphs and the relations with their effective pollinators. The species are synchronopatric, distylic, and self-incompatible. Though they share melittophilous traits, the main visitor and pollinator of C. globosa was the generalist and exotic bee Apis mellifera, while the only one of C. leucocephala was the oligoletic bee Ceblurgus longipalpis. These two latter species are restricted to the Caatinga of NE Brazil, contrasting with the wide distribution of Cordia globosa. While the fruit-set for C. globosa was high, independently if the pollen donor/stigma receptor was a pin (long-styled or thrum (short-styled individual, in C. leucocephala the fruit-set was low and occurred only when a thrum individual was the pollen donor. This raises the possibility of this species moving towards dioecy. The high natural fruit-set of C. globosa confirms the generalist bee as its effective pollinator. The low fruit-set after manual crosses in C. leucocephala may be due to low pollen viability. Additionally, the low natural fruit-set (two times lower than after crosses may be related with the foraging behavior of the specialist pollinator.Neste estudo comparamos a biologia reprodutiva de Cordia globosa e C. leucocephala para entender a função dos orfos florais e as relações com seus polinizadores efetivos. As espécies são sincronopátricas, distílicas e auto-incompatíveis. Embora elas compartilhem atributos melitófilos, o principal visitante e polinizador de C. globosa foi Apis mellifera, abelha generalista e exótica, enquanto o de C. leucocephala foi a abelha oligolética Ceblurgus longipalpis. Essas duas últimas espécies são restritas à Caatinga do Nordeste do Brasil, contrastando com a ampla distribuição de C. globosa. Enquanto a formação de frutos de C

  16. Gravitaxis in the flagellate Euglena gracilis--results from NiZeMi, clinostat and sounding rocket flights.

    Science.gov (United States)

    Häder, D P

    1994-05-01

    Many motile microorganisms including flagellates such as the green Euglena gracilis move up and down within the water column and use a number of external clues for their orientation, the most important of which may be light and gravity. The cells use positive phototaxis and negative gravitaxis to move closer to the surface of the water column which for energetic reasons is vital for their survival. However, most phytoplankton organisms cannot tolerate the bright irradiance of unfiltered solar radiation at the surface which also bleaches the photosynthetic pigments, disables the photosynthetic apparatus and impairs phototaxis, gravitaxis and motility in Euglena. Thus, it is not surprising that at higher irradiances negative phototaxis operates antagonistically to the responses described above to guide the cells into deeper water where they are protected from excessive radiation. Phototaxis and gravitaxis are not independent from one another: in a vertically positioned cuvette negative gravitaxis can be "titrated" by light impinging from above and is compensated at about 30 W m-2. While the photoreceptor for phototaxis has been identified in Euglena gracilis biochemically and spectroscopically, the gravireceptor is not yet known. Young cultures of Euglena gracilis show a positive gravitaxis, the ecological signficance of which is not yet understood while older cultures show negative gravitaxis. One hypothesis concerning the nature of graviperception is based on a passive physical process such as an asymmetric distribution of the mass within the cell. However, the observation that short term UV irradiation decreases the precision of negative gravitaxis rather indicates the involvement of an active physiological gravireceptor. Furthermore, some heavy metal ions have been found to change the direction of movement from positive to negative gravitaxis in young cells.

  17. A rapid phenol toxicity test based on photosynthesis and movement of the freshwater flagellate, Euglena agilis Carter

    International Nuclear Information System (INIS)

    Kottuparambil, Sreejith; Kim, Youn-Jung; Choi, Hoon; Kim, Mi-Sung; Park, Areum; Park, Jihae; Shin, Woongghi; Han, Taejun

    2014-01-01

    Highlights: • Rapid phenol toxicity tests (1 h) were developed based on Chl a fluorescence and the movement parameters of Euglena agilis. • Phenol significantly reduced F v /F m of PS II and rETRmax with EC50 values of 8.94 and 4.67 mM, respectively. • Among the movement parameters tested, velocity was the most sensitive biomarker with an EC50 of 3.17 mM. • The EC50 values for F v /F m , motility, and velocity appear to overlap the environmental permissible levels of phenol. - Abstract: Phenol, a monosubstituted aromatic hydrocarbon with various commercial uses, is a major organic constituent in industrial wastewaters. The ecotoxic action of phenol for aquatic environment is well known. In this study, rapid phenol toxicity tests (1 h) were developed based on chlorophyll a (Chl a) fluorescence and the movement parameters of the freshwater flagellate, Euglena agilis Carter. Phenol significantly reduced the maximum quantum yield (F v /F m ) of photosystem II (PS II) and the maximum photosynthetic electron transport rate (rETR max ) with median effective concentration (EC 50 ) values of 8.94 and 4.67 mM, respectively. Phenol reduced the motility and triggered change in the swimming velocity of the test organism. Among the parameters tested, velocity was the most sensitive biomarker with an EC 50 of 3.17 mM. The EC 50 values for F v /F m , motility, and velocity appear to overlap the permitted levels of phenol. In conclusion, the photosynthesis and movement of E. agilis can be fast and sensitive risk assessment parameters for the evaluation of phenol toxicity in municipal and industrial effluents

  18. High genetic diversity and fine-scale spatial structure in the marine flagellate Oxyrrhis marina (Dinophyceae uncovered by microsatellite loci.

    Directory of Open Access Journals (Sweden)

    Chris D Lowe

    2010-12-01

    Full Text Available Free-living marine protists are often assumed to be broadly distributed and genetically homogeneous on large spatial scales. However, an increasing application of highly polymorphic genetic markers (e.g., microsatellites has provided evidence for high genetic diversity and population structuring on small spatial scales in many free-living protists. Here we characterise a panel of new microsatellite markers for the common marine flagellate Oxyrrhis marina. Nine microsatellite loci were used to assess genotypic diversity at two spatial scales by genotyping 200 isolates of O. marina from 6 broad geographic regions around Great Britain and Ireland; in one region, a single 2 km shore line was sampled intensively to assess fine-scale genetic diversity. Microsatellite loci resolved between 1-6 and 7-23 distinct alleles per region in the least and most variable loci respectively, with corresponding variation in expected heterozygosities (H(e of 0.00-0.30 and 0.81-0.93. Across the dataset, genotypic diversity was high with 183 genotypes detected from 200 isolates. Bayesian analysis of population structure supported two model populations. One population was distributed across all sampled regions; the other was confined to the intensively sampled shore, and thus two distinct populations co-occurred at this site. Whilst model-based analysis inferred a single UK-wide population, pairwise regional F(ST values indicated weak to moderate population sub-division (0.01-0.12, but no clear correlation between spatial and genetic distance was evident. Data presented in this study highlight extensive genetic diversity for O. marina; however, it remains a substantial challenge to uncover the mechanisms that drive genetic diversity in free-living microorganisms.

  19. A rapid phenol toxicity test based on photosynthesis and movement of the freshwater flagellate, Euglena agilis Carter

    Energy Technology Data Exchange (ETDEWEB)

    Kottuparambil, Sreejith [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Kim, Youn-Jung [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Department of Marine Science, Incheon National University, Incheon 406 840 (Korea, Republic of); Green-Pioneer (Ltd.), Incheon National University, Incheon 406 840 (Korea, Republic of); Choi, Hoon; Kim, Mi-Sung; Park, Areum; Park, Jihae [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Shin, Woongghi [Department of Biology, Chungnam University, Daejeon 306 764 (Korea, Republic of); Han, Taejun, E-mail: hanalgae@hanmail.net [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Department of Marine Science, Incheon National University, Incheon 406 840 (Korea, Republic of); Green-Pioneer (Ltd.), Incheon National University, Incheon 406 840 (Korea, Republic of)

    2014-10-15

    Highlights: • Rapid phenol toxicity tests (1 h) were developed based on Chl a fluorescence and the movement parameters of Euglena agilis. • Phenol significantly reduced F{sub v}/F{sub m} of PS II and rETRmax with EC50 values of 8.94 and 4.67 mM, respectively. • Among the movement parameters tested, velocity was the most sensitive biomarker with an EC50 of 3.17 mM. • The EC50 values for F{sub v}/F{sub m}, motility, and velocity appear to overlap the environmental permissible levels of phenol. - Abstract: Phenol, a monosubstituted aromatic hydrocarbon with various commercial uses, is a major organic constituent in industrial wastewaters. The ecotoxic action of phenol for aquatic environment is well known. In this study, rapid phenol toxicity tests (1 h) were developed based on chlorophyll a (Chl a) fluorescence and the movement parameters of the freshwater flagellate, Euglena agilis Carter. Phenol significantly reduced the maximum quantum yield (F{sub v}/F{sub m}) of photosystem II (PS II) and the maximum photosynthetic electron transport rate (rETR{sub max}) with median effective concentration (EC{sub 50}) values of 8.94 and 4.67 mM, respectively. Phenol reduced the motility and triggered change in the swimming velocity of the test organism. Among the parameters tested, velocity was the most sensitive biomarker with an EC{sub 50} of 3.17 mM. The EC{sub 50} values for F{sub v}/F{sub m}, motility, and velocity appear to overlap the permitted levels of phenol. In conclusion, the photosynthesis and movement of E. agilis can be fast and sensitive risk assessment parameters for the evaluation of phenol toxicity in municipal and industrial effluents.

  20. Persistent Flagellate Hyperpigmentation

    Science.gov (United States)

    2017-04-28

    medical research or technical information as a publication/presentation, a new 59 MOW Form 3039 must be submitted for review and approval.) IA 6...directives.) D DISAPPROVED 40. PRINTED NAME. RANK/GRADE, TITLE OF REVIEWER 41 . REVIEWER SIGNATURE 42 . DATE Kevin linuma, SSgt/E-5, 59 MDW Public

  1. Value-chain analysis of freshwater apple snail (Pila globosa used for on-farm feeds in the freshwater prawn farming sector in Bangladesh

    Directory of Open Access Journals (Sweden)

    S.A.A. Nahid

    2013-12-01

    Full Text Available Growth of the freshwater prawn (Macrobrachium rosenbergii sector in Bangladesh since 1970s has been supported by natural availability of freshwater apple snail (Pila globosa, used for on-farm prawn feeds. The present study identified the current configuration of the value-chain benefits and constraints of freshwater apple snail in south-western Bangladesh in August 2011, based upon Rapid Market Appraisal (RMA approach. The site of snail collection was Chanda Beel in Gopalganj district, while trading, processing and final consumption was represented by Rayer Mahal Bazar in Khulna district. There were seven different nodes recognized throughout the value chain. Snail marketing was identified as a seasonal business and took place during June to November each year. Between 1995 and 2011 the price of whole snail, meat and shell has increased by 800%, 325% and 315%, respectively. The abundance of snail had been reduced and its demand has increased due to the expansion of the prawn farming industry. Prawn farmers preferred snail meat due to its’ low cost (US$ 0.21 kg-1 as a source of protein compared to commercial prawn feed (US$ 0.41 kg-1. Snail harvesting and processing were considered as additional livelihood options for the poor, where 60% of the labour involved in snail harvesting were women, and 95% the de-shelling workforce. Induced breeding in captivity and sustainable management in nature as well as development of commercial production of apple snails might reduce the pressure on ecosystems and positively contributed to the continued expansion of freshwater prawn farming in Bangladesh.

  2. Separation of betacyanins from purple flowers of Gomphrena globosa L. by ion-pair high-speed counter-current chromatography.

    Science.gov (United States)

    Spórna-Kucab, Aneta; Jagodzińska, Joanna; Wybraniec, Sławomir

    2017-03-17

    Betacyanins, known as antioxidants and chemopreventive natural compounds with colourful properties, were extracted from purple flowers of Gomphrena globosa L. belonging to the Amaranthaceae family and separated for the first time by ion-pair high-speed counter-current chromatography (HSCCC). The pigments were detected by LC-DAD-ESI-MS/MS technique. Separation of betacyanins (300mg) by HSCCC was accomplished in four solvent systems: tert-butyl methyl ether - butanol - acetonitrile - water (0.7% and 1.0% HFBA - heptafluorobutyric acid - system I and III) and tert-butyl methyl ether - butanol - methanol - water (0.7% and 1.0% HFBA - system II and IV) (2:2:1:5, v/v/v/v) in the head-to-tail mode. The mobile phase (aqueous phase) was run at 2.0ml/min and the column rotation speed was 860rpm. The applied systems enabled to study the influence of HFBA concentration as well as systems polarity on betacyanins separation. Comparison of the systems containing 0.7% HFBA (systems I-II) demonstrates that the replacement of acetonitrile by methanol increases the resolution (R s ) between all betacyanins and does not influence the retention of the stationary phase (S f =76%). Higher concentration of the acid in systems III-IV slightly decreases S f to 71% in the systems with 1.0% HFBA. Comparison of the resolution values for betacyanins in the systems with 0.7% and 1.0% HFBA demonstrates that higher concentration of the acid improves the separation effectiveness for all betacyanins as a result of increasing of the chemical affinity of the pigments to the organic stationary phase in HSCCC. The systems III-IV with 1% HFBA are the most effective for the separation of all the studied betacyanins. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Extra-chromosomal DNA maintenance in Bacillus subtilis, dependence on flagellation factor FliF and moonlighting mediator EdmS.

    Science.gov (United States)

    Hakumai, Yuichi; Shimomoto, Kouko; Ashiuchi, Makoto

    2015-05-15

    Extra-chromosomal DNA maintenance (EDM) as an important process in the propagation and genetic engineering of microbes. Bacillus subtilis EdmS (formerly PgsE), a protein comprising 55 amino acids, is a mediator of the EDM process. In this study, the effect of mutation of global regulators on B. subtilis EDM was examined. Mutation of the swrA gene abolished EdmS-mediated EDM. It is known that swrA predominantly regulates expression of the fla/che operon in B. subtilis. We therefore performed EDM analysis using fla/che-deletion mutants and identified an EDM-mediated EDM cooperator in the flgB-fliL region. Further genetic investigation identified the flagellation factor FliF is a crucial EDM cooperator. To our knowledge, this is the first observation of the moonlighting function of FliF in DNA maintenance. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Buddleja globosa (matico) prevents collagen-induced platelet activation by decreasing phospholipase C-gamma 2 and protein kinase C phosphorylation signaling.

    Science.gov (United States)

    Fuentes, Manuel; Sepúlveda, Cesar; Alarcón, Marcelo; Palomo, Iván; Fuentes, Eduardo

    2018-01-01

    Platelets play a key role in thrombosis and cardiovascular diseases. Medicinal plants could be one of the most important factors that influence risks for platelet activation. Buddleja globosa (known as "matico") is a medicinal plant with many biological activities. The high content of polyphenols suggest that matico could have antiplatelet activity. The present study was aimed at evaluating mechanisms of antiplatelet action of an extract of matico. We demonstrated that matico extract at low concentrations and in a concentration dependent manner (0.05-1 mg/mL) was a potent inhibitor of platelet aggregation in response to collagen, convulsion and ADP (IC 50 values was 61 μg/mL, 72 μg/mL and 290 μg/mL, respectively). In this sense matico extract exerted the greatest antiaggregant activity induced by collagen. Similarly, matico showed a decrease in % of positive platelet for P-selectina (vehicle, 0.01, 0.05, 0.1, 0.5 and 1 mg/mL were 32 ± 2%, 29 ± 2 (p < 0.05), 19 ± 1 (p < 0.01), 15 ± 2 (p < 0.01), 10 ± 1% (p < 0.01) and 7 ± 2% (p < 0.01), respectively) and PAC-1 binding (vehicle, 0.01, 0.05, 0.1, 0.5 and 1 mg/mL were 59 ± 1, 58 ± 3 (n.s), 55 ± 2 (p < 0.05), 50 ± 2 (p < 0.01), 38 ± 1 (p < 0.01), 36 ± 2 (p < 0.01). The cellular mechanism for the antiplatelet activity of matico might be mediated by the inhibition of phospholipase C-gamma 2 and protein kinase C phosphorylation. This beneficial property of matico may be of importance in thrombosis, in which platelet activation and aggregation are important determinants of thrombus initiation and development, and may contribute to the beneficial effects of matico intake in the prevention of cardiovascular diseases.

  5. Buddleja globosa (matico prevents collagen-induced platelet activation by decreasing phospholipase C-gamma 2 and protein kinase C phosphorylation signaling

    Directory of Open Access Journals (Sweden)

    Manuel Fuentes

    2018-01-01

    Full Text Available Platelets play a key role in thrombosis and cardiovascular diseases. Medicinal plants could be one of the most important factors that influence risks for platelet activation. Buddleja globosa (known as “matico” is a medicinal plant with many biological activities. The high content of polyphenols suggest that matico could have antiplatelet activity. The present study was aimed at evaluating mechanisms of antiplatelet action of an extract of matico. We demonstrated that matico extract at low concentrations and in a concentration dependent manner (0.05–1 mg/mL was a potent inhibitor of platelet aggregation in response to collagen, convulsion and ADP (IC50 values was 61 μg/mL, 72 μg/mL and 290 μg/mL, respectively. In this sense matico extract exerted the greatest antiaggregant activity induced by collagen. Similarly, matico showed a decrease in % of positive platelet for P-selectina (vehicle, 0.01, 0.05, 0.1, 0.5 and 1 mg/mL were 32 ± 2%, 29 ± 2 (p < 0.05, 19 ± 1 (p < 0.01, 15 ± 2 (p < 0.01, 10 ± 1% (p < 0.01 and 7 ± 2% (p < 0.01, respectively and PAC-1 binding (vehicle, 0.01, 0.05, 0.1, 0.5 and 1 mg/mL were 59 ± 1, 58 ± 3 (n.s, 55 ± 2 (p < 0.05, 50 ± 2 (p < 0.01, 38 ± 1 (p < 0.01, 36 ± 2 (p < 0.01. The cellular mechanism for the antiplatelet activity of matico might be mediated by the inhibition of phospholipase C-gamma 2 and protein kinase C phosphorylation. This beneficial property of matico may be of importance in thrombosis, in which platelet activation and aggregation are important determinants of thrombus initiation and development, and may contribute to the beneficial effects of matico intake in the prevention of cardiovascular diseases.

  6. Distribución de Taxus globosa (Taxaceae en México: Modelos ecológicos de nicho, efectos del cambio del uso de suelo y conservación Distribution of Taxus globosa (Taxaceae in Mexico: Ecological niche modeling, effects of land use change and conservation

    Directory of Open Access Journals (Sweden)

    RAÚL CONTRERAS-MEDINA

    2010-01-01

    Full Text Available Taxus globosa es una gimnosperma que habita principalmente en los bosques templados de México y el norte de América Central, y que está considerada como amenazada por las agencias de conservación tanto mexicanas como internacionales. En México, una de las mayores amenazas para la mayoría de las especies de los bosques nublados es la pérdida de hábitat, la cual se propicia por la modificación de la cobertura vegetal por factores antropogénicos. Con base en 73 registros de herbario se obtuvo la distribución potencial de la especie mediante el algoritmo Maxent. Asimismo, a partir del modelo obtenido se analizó la modificación de la cobertura vegetal durante tres períodos (1976, 1996 y 2000 y su influencia en la distribución potencial de esta especie. Su distribución potencial fue evaluada en relación con el actual Sistema Nacional de Áreas Naturales Protegidas a nivel federal (ANPs de México y las Regiones Terrestres Prioritarias para la Conservación (RTPs, con el fin de determinar el papel de estas áreas en su conservación y manejo. Los modelos de distribución potencial muestran que existe una reducción importante del área de distribución (hasta el 84 % al existir un cambio de uso de suelo. La especie está mal representada en las ANPs, pues menos del 10 % de su área potencial se encuentra dentro de estas áreas de protección federal. Este tipo de análisis representa una herramienta importante en biogeografía y conservación, así como en otras áreas del quehacer biológico, debido a su habilidad predictiva. Nuestros resultados muestran la urgencia que existe de conservar algunos parches de bosques templados mexicanos (principalmente los bosques nublados para garantizar la existencia de esta especie.Taxus globosa is a gymnosperm inhabiting Mexican and northern Central American temperate forests, and it has been considered as threatened by Mexican and international conservancy agencies. In México, habitat loss is one

  7. [Mutants of bacterium Azospirillum brasilense Sp245 with Omegon insertion in mmsB or fabG genes of lipid metabolism are defective in motility and flagellation].

    Science.gov (United States)

    Kovtunov, E A; Shelud'ko, A V; Chernyshova, M P; Petrova, L P; Katsy, E I

    2013-11-01

    Bacteria Azospirillum brasilense have mixed flagellation: in addition to the polar flagellum, numerous lateral flagella are formed in their cells on medium with increased density. Flagella determine the active swimming and swarming capacities of azospirilla. Using A. brasilense Sp245 as an example, we showed that the Omegon-Km artificial transposon insertion into the chromosomal gene for 3-hydroxyisobutyrate dehydrogenase (mmsB) was concurrent with the appearance of significant defects in the formation of polar flagella and with the paralysis of lateral flagella. The Sp245 mutant with the Omegon insertion into the plasmid AZOBR_p1-borne gene for 3-oxoacyl-[acyl-carrier protein]-reductase (fabG) showed the complete loss of flagella and the swarming capacity, as well as significant defects in polar flagellar assembly (though some cells are still motile in liquid medium). The viability of the A. brasilense Sp245 mutants with the Omegon insertion into the mmsB or fabG gene was not reduced. No considerable differences in the fatty acid composition of whole cell lipid extracts were found for the A. brasilense Sp245 strain and its mmsB and fabG mutants.

  8. Minimum Requirements of Flagellation and Motility for Infection of Agrobacterium sp. Strain H13-3 by Flagellotropic Bacteriophage 7-7-1

    Science.gov (United States)

    Yen, Jiun Y.; Broadway, Katherine M.

    2012-01-01

    The flagellotropic phage 7-7-1 specifically adsorbs to Agrobacterium sp. strain H13-3 (formerly Rhizobium lupini H13-3) flagella for efficient host infection. The Agrobacterium sp. H13-3 flagellum is complex and consists of three flagellin proteins: the primary flagellin FlaA, which is essential for motility, and the secondary flagellins FlaB and FlaD, which have minor functions in motility. Using quantitative infectivity assays, we showed that absence of FlaD had no effect on phage infection, while absence of FlaB resulted in a 2.5-fold increase in infectivity. A flaA deletion strain, which produces straight and severely truncated flagella, experienced a significantly reduced infectivity, similar to that of a flaB flaD strain, which produces a low number of straight flagella. A strain lacking all three flagellin genes is phage resistant. In addition to flagellation, flagellar rotation is required for infection. A strain that is nonmotile due to an in-frame deletion in the gene encoding the motor component MotA is resistant to phage infection. We also generated two strains with point mutations in the motA gene resulting in replacement of the conserved charged residue Glu98, which is important for modulation of rotary speed. A change to the neutral Gln caused the flagellar motor to rotate at a constant high speed, allowing a 2.2-fold-enhanced infectivity. A change to the positively charged Lys caused a jiggly motility phenotype with very slow flagellar rotation, which significantly reduced the efficiency of infection. In conclusion, flagellar number and length, as well as speed of flagellar rotation, are important determinants for infection by phage 7-7-1. PMID:22865074

  9. Phytoremediation assessment of Gomphrena globosa and Zinnia elegans grown in arsenic-contaminated hydroponic conditions as a safe and feasible alternative to be applied in arsenic-contaminated soils of the Bengal Delta.

    Science.gov (United States)

    Signes-Pastor, A J; Munera-Picazo, S; Burló, F; Cano-Lamadrid, M; Carbonell-Barrachina, A A

    2015-06-01

    Several agricultural fields show high contents of arsenic because of irrigation with arsenic-contaminated groundwater. Vegetables accumulate arsenic in their edible parts when grown in contaminated soils. Polluted vegetables are one of the main sources of arsenic in the food chain, especially for people living in rural arsenic endemic villages of India and Bangladesh. The aim of this study was to assess the feasibility of floriculture in the crop rotation system of arsenic endemic areas of the Bengal Delta. The effects of different arsenic concentrations (0, 0.5, 1.0, and 2.0 mg As L(-1)) and types of flowering plant (Gomphrena globosa and Zinnia elegans) on plant growth and arsenic accumulation were studied under hydroponic conditions. Total arsenic was quantified using atomic absorption spectrometer with hydride generation (HG-AAS). Arsenic was mainly accumulated in the roots (72 %), followed by leaves (12 %), stems (10 %), and flowers (phytoremediation capacities as other wild species, such as ferns. However, they behaved as arsenic tolerant plants and grew and bloomed well, without showing any phytotoxic signs. This study proves that floriculture could be included within the crop rotation system in arsenic-contaminated agricultural soils, in order to improve food safety and also food security by increasing farmer's revenue.

  10. Longitudinal variation of attributes from flagellate protozoan community in tropical streams = Variação longitudinal dos atributos da comunidade de protozoários flagelados de riachos tropicais

    Directory of Open Access Journals (Sweden)

    Janielly Carvalho Camargo

    2011-04-01

    Full Text Available This study verified the existence of longitudinal patterns in speciescomposition, richness, density and biomass of flagellate protozoan in tropical streams and investigated whether the possible zonation patterns are different between two periods of the year. For this, samplings were carried out in three regions from 10 streams, during the summer and winter. The flagellate community may be considered species-rich, because it was represented by 106 taxa, belonging to 8 orders and 1 residual group. The values of density and biomass are greater than those commonly found in other lotic environments, with mean values close to 2.3x104 cels. mL-1 and 150.8 ƒÊgC L-1. We did not observe any conspicuous and significant longitudinal pattern of the attributes from flagellates community. Only temporal variations of these attributes were verified. The Pearson Correlation evidenced that this temporal patterns was mainly driven by the nutrients availability, temperature and dissolved oxygen, since, the higher values of species richness, density and biomass were recorded during the winter, when the higher concentrations of nutrients and dissolved oxygen and lower temperatures were registered. In summary, the absence of patterns may be ascribed to the unidirectional and continuous flow from lotic environments.O presente estudo objetivou verificar a existencia de padroes longitudinais de composicao, riqueza de especies, densidade e biomassa da comunidade de protozoarios flagelados de riachos tropicais e, ainda, investigar se os possiveis padroes de zonacao sao diferentes entre dois periodos do ano. Foram realizadas coletas em tres regioes ao longo de dez riachos, durante os periodos de verao e inverno. A comunidade de protozoarios flagelados pode ser considerada bastante rica, sendo representada por 106 taxons pertencentes a oito ordens e um grupo residual. Os valores de densidade e biomassa registrados encontram-se acima dos valores comumente encontradosem

  11. Contribución al conocimiento de la morfología de la semilla, la germinación y el desarrollo de las plántulas de Beilschmiedia sulcata (R. et P. Kostem y Nectandra globosa (Aublet Mez. (Lauraceae

    Directory of Open Access Journals (Sweden)

    Mauricio Pinedo Guerrero

    2000-01-01

    Full Text Available The fruit of Beilschmiediasulcata (R. et P Kosterm is an ovoidellipsoid berry and the elipsoidseed has a papiraceous seedcoat and a broad, straight embryo.The seedling is criptocotylar andgermination hypogeus. The fruit of Nectandra globosa(Aublet Mez. is a drupe in form of a globe,sphere seed has a coriaceus seed coat and a broad, straight embryo. The seedling iscriptocotilar and germination is hypogeus. The percentage of germination for B. sulcatais 95%and for N. globosais 6%. The seedlig develops 5 – 6 squamous protophylls before it produceseophylls; it has a well developed radical system lacking root hairs.

  12. Current Knowledge of the Life Cycles of

    NARCIS (Netherlands)

    Peperzak, L.; Gäbler-Schwarz, S.

    2012-01-01

    Despite continuous efforts since the 1950s and more recent advances in culturing flagellates and nonflagellate cells of the prymnesiophyte Phaeocystis, a number of different life-cycle models exist today that appear to apply for P. globosa Scherff. and P. antarctica G. Karst., both spherical colony

  13. Evolution of parasitism in kinetoplastid flagellates

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Julius; Skalický, Tomáš; Týč, Jiří; Votýpka, Jan; Yurchenko, Vyacheslav

    2014-01-01

    Roč. 195, č. 2 (2014), s. 115-122 ISSN 0166-6851 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Evolution * Phylogeny * Vectors * Diversity * Parasitism * Trypanosome Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.787, year: 2014

  14. 124 Prevalence of Henneguya Chrysichthys (Flagellated Protozoa ...

    African Journals Online (AJOL)

    User

    oil immersion objectives (XL 00) of the microscope. Also a drop of whole blood was placed on a slide and allowed to clot, contraction of the clot left a circle of .... parasites invading fish body during wet season. The length of fish is usually.

  15. Metalycaea globosa stephensen, a valid species of Oxycephalidae (Amphipoda, Hyperiidea)

    Digital Repository Service at National Institute of Oceanography (India)

    Nair

    stream_size 6 stream_content_type text/plain stream_name J_Plankton_Res_15_1171.pdf.txt stream_source_info J_Plankton_Res_15_1171.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  16. Aerobic kinetoplastid flagellate Phytomonas does not require heme for viability

    Czech Academy of Sciences Publication Activity Database

    Kořený, Luděk; Sobotka, Roman; Kovářová, Julie; Gnipová, Anna; Flegontov, Pavel; Horváth, A.; Oborník, Miroslav; Ayala, F. J.; Lukeš, Julius

    2012-01-01

    Roč. 109, č. 10 (2012), s. 3808-3813 ISSN 0027-8424 R&D Projects: GA ČR GA204/09/1667; GA ČR GA206/08/1423; GA ČR(CZ) GAP305/11/2179 Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z50200510 Keywords : cytochromes * respiration * sterols * protist Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.737, year: 2012 http://www.pnas.org/content/109/10/3808.full.pdf+html

  17. Differential response of marine flagellate communities to prokaryotic food quality

    Science.gov (United States)

    De Corte, D.; Paredes, G.; Sintes, E.; Herndl, G. J.

    2016-02-01

    Marine prokaryotes play a major role in the biogeochemical cycles. The main predators of prokaryotes are heterotrophic nanoflagellates (HNF). HNF are thus a major link connecting dissolved organic material through prokaryotic grazing to the higher trophic levels. However, little is known about the grazing specificity of HNF on specific prokaryotic taxa. Bacterial and archaeal microbes may have different nutritive values for the HNF communities, thus affecting growth rates and community composition of HNFs. In this study we investigated the influence of prey food quality on Cafeteria roenbergensis and on a natural HNF community isolated in the northern Adriatic Sea. Two Nitrosopumilus maritimus-related strains isolated from the northern Adriatic Sea (Nitrosopumilus adriaticus, Nitrosopumilus piranensis), two Nitrosococcus strains and two fast growing marine Bacteria (Pseudomonas marina and Marinobacter algicola) were fed to the HNFs. The two fast growing bacterial strains resulted in high growth rates of Cafeteria roenbergensis and the mixed HNF community, while the two Nitrosococcus strains did not. Cafeteria roenbergensis fed on N. adriaticus but it did not graze N. piranensis, suggesting that the subtle metabolic and physiological differences between these two closely related thaumarchaeal strains affect the grazing pressure to which they are exposed. Our study also indicates that prokaryotic community composition influences the composition of the HNF community.

  18. Collodictyon triciliatum and Diphylleia rotans (=Aulacomonas submarina) form a new family of flagellates (Collodictyonidae) with tubular mitochondrial cristae that is phylogenetically distant from other flagellate groups.

    Science.gov (United States)

    Brugerolle, Guy; Bricheux, Geneviève; Philippe, Hervé; Coffea, Gérard

    2002-03-01

    Comparative electron microscopic studies of Collodictyon triciliatum and Diphylleia rotans (=Aulacomonas submarina) showed that they share a distinctive flagellar transitional zone and a very similar flagellar apparatus. In both species, the basic couple of basal bodies and flagella #1 and #2 are connected to the dorsal and ventral roots, respectively. Collodictyon triciliatum has two additional basal bodies and flagella, #3 and #4, situated on each side of the basic couple, each of which also bears a dorsal root. The horseshoe-shaped arrangement of dictyosomes, mitochondria with tubular cristae and the deep ventral groove are very similar to those of Diphylleia rotans. These two genera have very specific features and are placed in a new family, Collodictyonidae, distinct from other eukaryotic groups. Electron microscopic observation of mitotic telophase in Diphylleia rotans revealed two chromosomal masses, surrounded by the nuclear envelope, within the dividing parental nucleus, as in the telophase stage of the heliozoan Actinophrys and the helioflagellate Dimorpha. Spindle microtubules arise from several MTOCs outside the nucleus, and several microtubules penetrate within the dividing nucleus, via pores at the poles. This semi-open type of orthomitosis is reminiscent of that of actinophryids. The SSU rDNA sequence of Diphylleia rotans was compared with that of all the eukaryotic groups that have a slow-evolving rDNA. Diphylleia did not strongly assemble with any group and emerged in a very poorly resolved part of the eukaryotic phylogenetic tree.

  19. 78 FR 47109 - Endangered and Threatened Wildlife and Plants; Endangered Status for Physaria globosa (Short's...

    Science.gov (United States)

    2013-08-02

    .... (dead nettle), Phacelia bipinnatifida (forest phacelia), Polygonatum biflorum (Solomon's seal), Sedum...-thickened roots with slender rhizomes. The stems are slender, erect, and up to 2 meters (m) (6 feet (ft... and root-tip chromosome counts by Matthews et al. (2002, pp. 17-23) validated this taxon's status as a...

  20. Polyancora globosa gen. sp. nov., an aeroaquatic fungus from Malaysian peat swamp forests.

    Science.gov (United States)

    Voglmayr, Hermann; Yule, Catherine M

    2006-10-01

    During an investigation of submerged leaves and twigs sampled from tropical peat swamp forests located in Peninsular Malaysia, an anamorphic fungus not attributable to a described genus was detected and isolated in pure culture. Conidial ontogeny was thoroughly studied and illustrated using both light and SEM, which revealed a unique conidial morphology. Analysis of partial nuLSU rDNA and ITS data revealed a phylogenetic position within the Xylariales (Ascomycota), but family affiliation remained unclear.

  1. Responses of the coastal bacterial community to viral infection of the algae Phaeocystis globosa

    NARCIS (Netherlands)

    Sheik, A.R.; Brussaard, C.P.D.; Lavik, G.; Lam, P.; Musat, N.; Krupke, A.; Littmann, S.; Strous, M.; Kuypers, M.M.M.

    2014-01-01

    The release of organic material upon algal cell lyses has a key role in structuring bacterial communities and affects the cycling of biolimiting elements in the marine environment. Here we show that already before cell lysis the leakage or excretion of organic matter by infected yet intact algal

  2. Exploring the environmental diversity of kinetoplastid flagellates in the high-throughput DNA sequencing era

    Czech Academy of Sciences Publication Activity Database

    d’Avila-Levy, C.M.; Boucinha, C.; Kostygov, A.; Carneiro Santos, H.L.; Morelli, K.A.; Grybchuk-Ieremenko, A.; Duval, L.; Votýpka, Jan; Yurchenko, V.; Grellier, P.; Lukeš, Julius

    2015-01-01

    Roč. 110, č. 8 (2015), s. 956-965 ISSN 0074-0276 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 EU Projects: European Commission(XE) 316304 Institutional support: RVO:60077344 Keywords : Kinetoplastea * metagenomics * metabarcoding * taxonomy * Trypanosomatida Subject RIV: EG - Zoology Impact factor: 1.789, year: 2015

  3. Seasonal variability in irradiance affects herbicide toxicity to the marine flagellate Dunaliella tertiolecta

    NARCIS (Netherlands)

    Sjollema, S.B.; Vavourakis, C.D.; van der Geest, H.G.; Vethaak, A.D.; Admiraal, W.

    2014-01-01

    Photosynthetically Active Radiation (PAR) and Ultraviolet Radiation (UVR) of the solar spectrum affect microalgae directly and modify the toxicity of phytotoxic compounds present in water. As a consequence seasonal variable PAR and UVR levels are likely to modulate the toxic pressure of contaminants

  4. Complete genome of Ignavibacterium album, a metabolically versatile, flagellated, facultative anaerobe from the phylum Chlorobi

    Directory of Open Access Journals (Sweden)

    Zhenfeng eLiu

    2012-05-01

    Full Text Available Prior to the recent discovery of Ignavibacterium album (I. album, anaerobic photoautotrophic green sulfur bacteria (GSB were the only cultivated members of the bacterial phylum Chlorobi. In contrast to GSB, sequence analysis of the 3.7-Mbp genome of I. album shows that this recently described member of the phylum Chlorobi is a chemoheterotroph with a versatile metabolism. I. album lacks genes for photosynthesis and sulfur oxidation but has a full set of genes for flagella and chemotaxis. The occurrence of genes for multiple electron transfer complexes suggests that I. album is capable of organoheterotrophy under both oxic and anoxic conditions. The occurrence of genes encoding enzymes for CO2 fixation as well as other enzymes of the reductive TCA cycle suggests that mixotrophy may be possible under certain growth conditions. However, known biosynthetic pathways for several amino acids are incomplete; this suggests that I. album is dependent upon on exogenous sources of these metabolites or employs novel biosynthetic pathways. Comparisons of I. album and other members of the phylum Chlorobi suggest that the physiology of the ancestors of this phylum might have been quite different from that of modern GSB.

  5. UV-B affects photosynthesis, ROS production and motility of the freshwater flagellate, Euglena agilis Carter

    Energy Technology Data Exchange (ETDEWEB)

    Kottuparambil, Sreejith [Institute of Green Environmental Research Center, University of Incheon, Incheon, 406 840 (Korea, Republic of); Shin, Woongghi [Department of Biology, Chungnam University, Daejeon, 306 764 (Korea, Republic of); Brown, Murray T. [School of Marine Science and Engineering, Plymouth University, Drake Circus, Plymouth PL4 8AA (United Kingdom); Han, Taejun, E-mail: hanalgae@hanmail.net [Institute of Green Environmental Research Center, University of Incheon, Incheon, 406 840 (Korea, Republic of); Department of Marine Science, University of Incheon, Incheon, 406 840 (Korea, Republic of)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer We proposed a hypothesis for the UV-B protective/adaptive mechanism in Euglena agilis. After moderate levels of UV-B radiation, ROS plays a signaling role to shut down photosynthetic system for protection against harmful UV radiation. Black-Right-Pointing-Pointer E. agilis exposed to excessive UV appears to become animal-like, investing all its stored energy into movement rather than into sustaining its photosynthetic machinery. Black-Right-Pointing-Pointer This adaptation allows E. agilis to avoid harmful UV and seek a safe place where the organism may regain its photosynthetic capacity for survival. - Abstract: The effects of ultraviolet B (UV-B; 295-320 nm) radiation on certain vital physiological (photosynthesis), biochemical (production of reactive oxygen species - ROS) and behavioral (motility and orientation) characteristics were investigated in the unicellular photoautotroph, Euglena agilis Carter. The photosynthetic performance of E. agilis was recorded after exposure of between 15 and 60 min followed by a period of recovery lasting 6-24 h under dim light (5-10 {mu}mol photons m{sup -2} s{sup -1}). The maximum quantum yield of PS II (F{sub v}/F{sub m}) was reduced to 65% and 14% of initial values immediately following 15 and 30 min UV-B exposure, but recovered to 100 and 86% of the initials, respectively. Values of rETR{sub max} in E. agilis exposed to 15 min UV-B were similar to those of the initials, but a 30 min UV exposure resulted in 75% reduction of rETR{sub max} with only a 43% recovery as compared with the initial after 24 h recovery. After a 60 min UV-B exposure, there were no Chl a fluorescence signals, and hence no F{sub v}/F{sub m} or rETR{sub max}. A UV dose-dependent increase in DCFH-DA fluorescence was found in E. agilis cells, reflecting an increase in ROS production. After exposures to UV-B for between 15 and 60 min, the percentages of motile cells in the population decreased to 76, 39 and 15%, respectively. Following 24 h in dim light, the percentage of motile cells increased to between 66% and 95% of the initial value. The velocity of non-irradiated cells was 60 {mu}m s{sup -1}, which decreased to 16-35 {mu}m s{sup -1} immediately following exposure for 15-60 min. After periods of time in dim light (6, 12 and 24 h) velocities had recovered to between 44 and 81% of the initial value. In untreated controls, the r-value was 0.23, indicating random movement of E. agilis, but it increased to 0.35 and 0.72 after exposure to UV-B for 30 and 60 min, respectively. There was a tendency towards vertical downward movement of cells proportional to the duration of exposure. The compactness of E. agilis decreased from 2.9 in controls to 1.8-2.3 in cells treated with UV-B although significant recovery followed. UV-B dose-dependent interaction between photosynthetic activity, ROS production and movement is discussed in terms of a UV-protective mechanism in E. agilis.

  6. Demonstration of glycosomes (microbodies) in the Bodonid flagellate Trypanoplasma borelli (Protozoa, Kinetoplastida)

    NARCIS (Netherlands)

    Opperdoes, Fred R.; Nohynkova, Eva; Schaftingen, Emile Van; Lambeir, Anne-Marie; Veenhuis, Marten; Roy, Joris Van

    1988-01-01

    Homogenates of Trypanoplasma borelli were subjected to subcellular fractionation by sequential differential and isopycnic centrifugation in sucrose. Glycerol-3-phosphate dehydrogenase and the glycolytic enzymes, glucosephosphate isomerase and triosephosphate isomerase, as well as the peroxisomal

  7. Unexplained complexity of the mitochondrial genome and transcriptome in kinetoplastid flagellates

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Julius; Hashimi, Hassan; Zíková, Alena

    2005-01-01

    Roč. 48, č. 5 (2005), s. 277-299 ISSN 0172-8083 R&D Projects: GA AV ČR IAA5022302 Grant - others:National Institutes of Health(US) 5R03TW6445-2 Institutional research plan: CEZ:AV0Z60220518 Keywords : RNA editing * kinetoplast DNA * mRNA stability Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.346, year: 2005

  8. Lineage-specific activities of a multipotent mitochondrion of trypanosomatid flagellates

    Czech Academy of Sciences Publication Activity Database

    Škodová-Sveráková, Ingrid; Verner, Zdeněk; Skalický, Tomáš; Votýpka, Jan; Horváth, A.; Lukeš, Julius

    2015-01-01

    Roč. 96, č. 1 (2015), s. 55-67 ISSN 0950-382X R&D Projects: GA ČR GAP305/12/2261; GA MŠk(CZ) EE2.3.30.0032; GA MŠk LH12104; GA ČR(CZ) GA14-23986S EU Projects: European Commission(XE) 316304 Institutional support: RVO:60077344 Keywords : cytochrome C-oxidase * alternative NADH dehydrogenase * blood stream forms Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.761, year: 2015

  9. FLAGELLATE CRYPTOBIA BRANCHIALIS (BODONIDA: KINETOPLASTIDA), ECTOPARASITE OF TILAPIA FROM THE SALTON SEA. (R826552)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  10. Exploring the environmental diversity of kinetoplastid flagellates in the high-throughput DNA sequencing era

    Directory of Open Access Journals (Sweden)

    Claudia Masini d’Avila-Levy

    2015-01-01

    Full Text Available The class Kinetoplastea encompasses both free-living and parasitic species from a wide range of hosts. Several representatives of this group are responsible for severe human diseases and for economic losses in agriculture and livestock. While this group encompasses over 30 genera, most of the available information has been derived from the vertebrate pathogenic genera Leishmaniaand Trypanosoma.Recent studies of the previously neglected groups of Kinetoplastea indicated that the actual diversity is much higher than previously thought. This article discusses the known segment of kinetoplastid diversity and how gene-directed Sanger sequencing and next-generation sequencing methods can help to deepen our knowledge of these interesting protists.

  11. SKELETAL DEVELOPMENT IN HERMESINUM ADRIATICUM ZACHARIAS, A FLAGELLATE FROM THE SALTON SEA, CALIFORNIA. (R826552)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  12. The immune response of hemocytes of the insect Oncopeltus fasciatus against the flagellate Phytomonas serpens.

    Directory of Open Access Journals (Sweden)

    Thiago L Alves e Silva

    Full Text Available The genus Phytomonas includes parasites that are etiological agents of important plant diseases, especially in Central and South America. These parasites are transmitted to plants via the bite of an infected phytophagous hemipteran. Despite the economic impact of these parasites, many basic questions regarding the genus Phytomonas remain unanswered, such as the mechanism by which the parasites cope with the immune response of the insect vector. In this report, using a model of systemic infection, we describe the function of Oncopeltus fasciatus hemocytes in the immune response towards the tomato parasite Phytomonas serpens. Hemocytes respond to infection by trapping parasites in nodular structures and phagocytizing the parasites. In electron microscopy of hemocytes, parasites were located inside vacuoles, which appear fused with lysosomes. The parasites reached the O. fasciatus salivary glands at least six hours post-infection. After 72 hours post-infection, many parasites were attached to the salivary gland outer surface. Thus, the cellular responses did not kill all the parasites.

  13. Effects of protozoan grazing on colony formation in Phaeocystis globosa (Prymnesiophyceae) and the potential costs and benefits

    DEFF Research Database (Denmark)

    Jakobsen, Hans Henrik; Tang, K.W.

    2002-01-01

    . scintillans increased the mean colony size by up to 50 % relative to the controls, whereas grazing by G. dominans enhanced the mean colony size by up to 3-fold. Microscopic observations confirmed that N. scintillans was also able to ingest small colonies. In contrast, G. dominans apparently did not ingest...

  14. Draft Genome Sequence of a Highly Flagellated, Fast-Swimming Archaeon, Methanocaldococcus villosus Strain KIN24-T80 (DSM 22612)

    KAUST Repository

    Thennarasu, Sugumar

    2013-07-11

    We report the draft genome sequence of a hyperthermophilic Methanocaldococcus villosus strain, KIN24-T80. The gene associated with its heavy flagellum formation was annotated in the 1.2-Mb draft genome sequence, and this strain may be a good model system to study the extensive functional role of flagella and their fast motor activity.

  15. Draft Genome Sequence of a Highly Flagellated, Fast-Swimming Archaeon, Methanocaldococcus villosus Strain KIN24-T80 (DSM 22612)

    KAUST Repository

    Thennarasu, Sugumar; Poli Reddy, Dinesh Reddy; Antony, Aju; Yada, Madhava; Alqarawi, Sami; Neelamegam, Sivakumar

    2013-01-01

    We report the draft genome sequence of a hyperthermophilic Methanocaldococcus villosus strain, KIN24-T80. The gene associated with its heavy flagellum formation was annotated in the 1.2-Mb draft genome sequence, and this strain may be a good model system to study the extensive functional role of flagella and their fast motor activity.

  16. Changes in bacterial community composition and dynamics and viral mortality rates associated with enhanced flagellate grazing in a mesoeutrophic reservoir

    Czech Academy of Sciences Publication Activity Database

    Šimek, Karel; Pernthaler, J.; Weinbauer, M. G.; Horňák, K.; Dolan, J. R.; Nedoma, Jiří; Mašin, M.; Amann, R.

    2001-01-01

    Roč. 67, č. 6 (2001), s. 2723-2733 ISSN 0099-2240 R&D Projects: GA ČR GA206/99/0028; GA AV ČR IPP1011802 Grant - others:CNRS(FR) PICS1111 Keywords : bacterial community composition * protozoan grazing * viral lysis Subject RIV: EE - Microbiology, Virology Impact factor: 3.688, year: 2001

  17. Pseudotrichonympha leei, Pseudotrichonympha lifesoni, and Pseudotrichonympha pearti, new species of parabasalian flagellates and the description of a rotating subcellular structure

    Czech Academy of Sciences Publication Activity Database

    del Campo, J.; James, E. R.; Hirakawa, Y.; Fiorito, R.; Kolísko, Martin; Irwin, N. A.T.; Mathur, V.; Boscaro, V.; Hehenberger, E.; Karnkowska, A.; Scheffrahn, R. H.; Keeling, P. J.

    2017-01-01

    Roč. 7, NOV 27 (2017), č. článku 16349. ISSN 2045-2322 Institutional support: RVO:60077344 Keywords : lower termites * phylogeny * symbiosis * protozoa * primers * tool Subject RIV: EB - Gene tics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 4.259, year: 2016

  18. Changes in the flagellar bundling time account for variations in swimming behavior of flagellated bacteria in viscous media

    Science.gov (United States)

    Qu, Zijie; Temel, Fatma; Henderikx, Rene; Breuer, Kenneth

    2017-11-01

    The motility of bacteria E.coli in viscous fluids has been widely studied, although conflicting results on the effect of viscosity on swimming speed abound. The swimming mode of wild-type E.coli is idealized as a run-and-tumble sequence in which periods of straight swimming at a constant speed are randomly interrupted by a tumble, defined as a sudden change of direction with a very low speed. Using a tracking microscope, we follow cells for extended time and find that the swimming behavior of a single cell can exhibit a variety of behaviors including run-and-tumble and ``slow-random-walk'' in which the cells move at relatively low speed without the characteristic run. Although the characteristic swimming speed varies between individuals and in different polymer solutions, we find that the skewness of the speed distribution is solely a function of viscosity, and uniquely determines the ratio of the average speed to the characteristic run speed. Using Resistive Force Theory and the cell-specific measured characteristic run speed, we show that differences in the swimming behavior observed in solutions of different viscosity are due to changes in the flagellar bundling time, which increases as the viscosity rises, due to lower rotation rate of the flagellar motor. National Science Foundation.

  19. Taxonomic identity and physiological ecology of Chlamydomonas hedleyi sp. nov. , algal flagellate symbiont from the foraminifer Archaias angulatus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J J; Crockett, L J; Hagen, J; Stone, R J

    1975-12-31

    The fine structure of the symbiotic alga isolated from the foraminiferan Archaias angulatus (Fichtel et Moll) DeMontfort is typical of the Chlorophyceae of the volvocalean and chlorococcalean lines. Spherical non-motile cells, 10--14 ..mu..m in diameter, characterize the dominant life cycle phase. Long oval motile forms with truncated apices are present 3--5 days after transfer to fresh medium. The pyrenoids are embedded anteriorly in the singly bilobed chloroplast and are surrounded by a sheath of starch platelets. In spite of the non-motile state of cells in older cultures (which is perhaps a reflection of its normally symbiotic condition), the alga is identified as a species of the volvocalean genus Chlamydomonas and is named C. hedleyi sp. nov. The symbiont has no vitamin or organic requirements but growth is increased threefold in the presence of thiamine, and twofold in the presence of 1 ..mu..m glutamic acid, histidine and methionine. Urea was the best nitrogen source tested. Purines and pyrimidines did not serve as nitrogen sources. Chlamydomonas hedleyi grows well in a salinity range of 6- greater than 52 per thousand and a pH range of 6--8.5. 7.04 x 10/sup -7/ M carbon h/sup -1/ g/sup -1/ was fixed by the symbiont, 57 percent being released into the medium as a chromatographically homogeneous organic molecule provisionally identified as mannitol.

  20. Flagellate dermatitis caused by shiitake mushrooms Dermatite flagelada após a ingestão de fungos shiitake

    Directory of Open Access Journals (Sweden)

    Lidia Marilia Poppe

    2012-06-01

    Full Text Available Shiitake (Lentinus edodes is the second most consumed mushroom in the world. It has long been known in Asian medicine for its anticarcinogenic, antihypertensive and serum cholesterol level reduction properties. Nevertheless, the consumption of raw or not well-cooked mushrooms may cause skin eruptions which usually occur 24 to 48 hours after ingestion and are characterized by linearly arranged pruritic erythematous papules and plaques. We present a 36-year-old patient that developed typical symptoms 24 hours after consumption of shiitake mushrooms and summarize therapeutic options and particularities of this disease.Shiitake (Lentinus edodes é o segundo tipo de cogumelo mais consumido no mundo. Suas propriedades terapêuticas antitumorais, anti-hipertensivas e redutoras dos níveis elevados de colesterol são há muito conhecidas pela população asiática. Após ingestão desse cogumelo, cru ou malcozido, podem desenvolver-se lesões eritematosas lineares, pruriginosas, que surgem após 24 ou 48 horas em todo o corpo. Apresentamos um paciente de 36 anos com anamnese e clínica típicos, e comentamos as alternativas terapêuticas e nuances dessa dermatose.

  1. The immune response of carp to blood flagellates : a model for studies on disease resistance and stress

    NARCIS (Netherlands)

    Saeij, J.P.J.

    2002-01-01

    To date, aquaculture accounts for 25% of the total world supply of (shell)fish for human consumption, a relative contribution that is expected to increase with time. The increased global demand for (shell)fish has lead to a further intensification of aquaculture with

  2. Actin and ubiquitin protein sequences support a cercozoan/foraminiferan ancestry for the plasmodiophorid plant pathogens.

    Science.gov (United States)

    Archibald, John M; Keeling, Patrick J

    2004-01-01

    The plasmodiophorids are a group of eukaryotic intracellular parasites that cause disease in a variety of economically significant crops. Plasmodiophorids have traditionally been considered fungi but have more recently been suggested to be members of the Cercozoa, a morphologically diverse group of amoeboid, flagellate, and amoeboflagellate protists. The recognition that Cercozoa constitute a monophyletic lineage has come from phylogenetic analyses of small subunit ribosomal RNA genes. Protein sequence data have suggested that the closest relatives of Cercozoa are the Foraminifera. To further test a cercozoan origin for the plasmodiophorids, we isolated actin genes from Plasmodiophora brassicae, Sorosphaera veronicae, and Spongospora subterranea, and polyubiquitin gene fragments from P. brassicae and S. subterranea. We also isolated actin genes from the chlorarachniophyte Lotharella globosa. In protein phylogenies of actin, the plasmodiophorid sequences consistently branch with Cercozoa and Foraminifera, and weakly branch as the sister group to the foraminiferans. The plasmodiophorid polyubiquitin sequences contain a single amino acid residue insertion at the functionally important processing point between ubiquitin monomers, the same place in which an otherwise unique insertion exists in the cercozoan and foraminiferan proteins. Taken together, these results indicate that plasmodiophorids are indeed related to Cercozoa and Foraminifera, although the relationships amongst these groups remain unresolved.

  3. Probing into the diversity of trypanosomatid flagellates parasitizing insect hosts in South-West China reveals both endemism and global dispersal

    Czech Academy of Sciences Publication Activity Database

    Votýpka, Jan; Maslov, D. A.; Yurchenko, V.; Jirků, Milan; Kment, P.; Lun, Z.-R.; Lukeš, Julius

    2010-01-01

    Roč. 54, č. 1 (2010), s. 243-253 ISSN 1055-7903 Institutional research plan: CEZ:AV0Z60220518 Keywords : trypanosomatids * phylogeny * diversity * insects Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.889, year: 2010

  4. Caspase-1 but Not Caspase-11 Is Required for NLRC4-Mediated Pyroptosis and Restriction of Infection by Flagellated Legionella Species in Mouse Macrophages and In Vivo.

    Science.gov (United States)

    Cerqueira, Daiane M; Pereira, Marcelo S F; Silva, Alexandre L N; Cunha, Larissa D; Zamboni, Dario S

    2015-09-01

    Gram-negative bacteria from the Legionella genus are intracellular pathogens that cause a severe form of pneumonia called Legionnaires' disease. The bacteria replicate intracellularly in macrophages, and the restriction of bacterial replication by these cells is critical for host resistance. The activation of the NAIP5/NLRC4 inflammasome, which is readily triggered in response to bacterial flagellin, is essential for the restriction of bacterial replication in murine macrophages. Once activated, this inflammasome induces pore formation and pyroptosis and facilitates the restriction of bacterial replication in macrophages. Because investigations related to the NLRC4-mediated restriction of Legionella replication were performed using mice double deficient for caspase-1 and caspase-11, we assessed the participation of caspase-1 and caspase-11 in the functions of the NLRC4 inflammasome and the restriction of Legionella replication in macrophages and in vivo. By using several species of Legionella and mice singly deficient for caspase-1 or caspase-11, we demonstrated that caspase-1 but not caspase-11 was required for pore formation, pyroptosis, and restriction of Legionella replication in macrophages and in vivo. By generating F1 mice in a mixed 129 × C57BL/6 background deficient (129 × Casp-11(-/-) ) or sufficient (129 × C57BL/6) for caspase-11 expression, we found that caspase-11 was dispensable for the restriction of Legionella pneumophila replication in macrophages and in vivo. Thus, although caspase-11 participates in flagellin-independent noncanonical activation of the NLRP3 inflammasome, it is dispensable for the activities of the NLRC4 inflammasome. In contrast, functional caspase-1 is necessary and sufficient to trigger flagellin/NLRC4-mediated restriction of Legionella spp. infection in macrophages and in vivo. Copyright © 2015 by The American Association of Immunologists, Inc.

  5. Assessment of Flagellate Diversity at Deep-Sea Hydrothermal Vents Using the Combined Approach of Culture-Dependent and Culture-Independent Methods

    National Research Council Canada - National Science Library

    Atkins, Michael

    2000-01-01

    .... Molecular and ultrastructural evidence point to one of the isolates. Ancyromonas, as a plausible candidate for the closest relative to the common ancestor of Metazoans, Fungi, and Choanoglagellates...

  6. Bacterial Feeders, the Nematode Caenorhabditis elegans and the Flagellate Cercomonas longicauda, have different Effects on Outcome of Competition among the Pseudomonas Biocontrol Strains CHA0 and DSS73

    DEFF Research Database (Denmark)

    Pedersen, Annette; Nybroe, Ole; Winding, Anne

    2009-01-01

    How bacterial feeding fauna affects colonization and survival of bacteria in soil is not well understood, which constrains the applicability of bacterial inoculants in agriculture. This study aimed to unravel how food quality of bacteria and bacterial feeders with different feeding habits (the......50090 or one of two biocontrol strains P. fluorescens CHA0 or Pseudomonas sp. DSS73) or combinations of two bacterial strains. DSM50090 is a suitable food bacterium, DSS73 is of intermediate food quality, and CHA0 is inedible to the bacterial feeders. Bacterial and protozoan cell numbers were measured...... predation pressure. Hence, the results suggested that the outcome of competition among bacteria depended on their ability to cope with the prevailing bacterial predator....

  7. Strains of the heterotrophic flagellate Bodo designis from different environments vary considerably with respect to salinity preference and SSU rRNA gene composition

    DEFF Research Database (Denmark)

    Koch, Trine A; Ekelund, Flemming

    2005-01-01

    The morpho species Bodo designis is widespread and abundant globally in highly contrasting terrestrial and aquatic ecosystems. Whether the forms of Bodo designis from contrasting environments are conspecific, i.e. largely genetically identical, or whether they merely share the external morphology...

  8. A simple and low-toxic method of preparing small specimens of bacteria, flagellates and their likes for Scanning Electron Microscopy

    DEFF Research Database (Denmark)

    Møller, O. S.; Buchman, K.; Dalsgaard, Inger

    2013-01-01

    The preparation of samples of bacteria and other very small organisms (Electron Microscopy is often complex and intricate, which typically involve the use of specialized filter systems, complex handling and toxic chemicals. Based on the methods described in the literature...

  9. The origin of exon 3 skipping of paternal GLOBOSA pre-mRNA in some Nicotiana tabacum lines correlates with a point mutation of the very last nucleotide of the exon

    Czech Academy of Sciences Publication Activity Database

    Fulneček, Jaroslav; Matyášek, Roman

    2016-01-01

    Roč. 291, č. 2 (2016), s. 801-818 ISSN 1617-4615 R&D Projects: GA ČR GBP501/12/G090; GA ČR GA13-10057S; GA ČR(CZ) GA14-34632S Institutional support: RVO:68081707 Keywords : Flowering * Floral genes * Alternative splicing Subject RIV: BO - Biophysics Impact factor: 2.979, year: 2016

  10. A Constitutively Mannose-Sensitive Agglutinating Salmonella enterica subsp. enterica Serovar Typhimurium Strain, Carrying a Transposon in the Fimbrial Usher Gene stbC, Exhibits Multidrug Resistance and Flagellated Phenotypes

    Directory of Open Access Journals (Sweden)

    Kuan-Hsun Wu

    2012-01-01

    Full Text Available Static broth culture favors Salmonella enterica subsp. enterica serovar Typhimurium to produce type 1 fimbriae, while solid agar inhibits its expression. A transposon inserted in stbC, which would encode an usher for Stb fimbriae of a non-flagellar Salmonella enterica subsp. enterica serovar Typhimurium LB5010 strain, conferred it to agglutinate yeast cells on both cultures. RT-PCR revealed that the expression of the fimbrial subunit gene fimA, and fimZ, a regulatory gene of fimA, were both increased in the stbC mutant when grown on LB agar; fimW, a repressor gene of fimA, exhibited lower expression. Flagella were observed in the stbC mutant and this phenotype was correlated with the motile phenotype. Microarray data and RT-PCR indicated that the expression of three genes, motA, motB, and cheM, was enhanced in the stbC mutant. The stbC mutant was resistant to several antibiotics, consistent with the finding that expression of yhcQ and ramA was enhanced. A complementation test revealed that transforming a recombinant plasmid possessing the stbC restored the mannose-sensitive agglutination phenotype to the stbC mutant much as that in the parental Salmonella enterica subsp. enterica serovar Typhimurium LB5010 strain, indicating the possibility of an interplay of different fimbrial systems in coordinating their expression.

  11. New Insights on the Ecology of Free-living, Heterotrophic Nanoflagellates Based on the Use of Molecular Biological Approaches

    National Research Council Canada - National Science Library

    Lim, Lin

    1997-01-01

    Nanoplanktonic protists comprise a diverse assemblage of flagellate species. Current methods for identifying small protists do not readily permit identification and enumeration of nanoplanktonic flagellates in cultures or field samples...

  12. Trade-off between reproduction and lifespan of the rotifer Brachionus plicatilis under different food conditions.

    Science.gov (United States)

    Sun, Yunfei; Hou, Xinying; Xue, Xiaofeng; Zhang, Lu; Zhu, Xuexia; Huang, Yuan; Chen, Yafen; Yang, Zhou

    2017-11-13

    Phaeocystis globosa, one of the most typical red tide-forming species, is usually mixed in the food composition of rotifers. To explore how rotifers respond by adjusting life history strategy when feeding on different quality foods, we exposed the rotifer Brachionus plicatilis to cultures with 100% Chlorella, a mixture of 50% P. globosa and 50% Chlorella, or 100% P. globosa. Results showed that rotifers exposed to 100% Chlorella or to mixed diets produced more total offspring and had higher age-specific fecundity than those exposed to 100% P. globosa. Food combination significantly affected the net reproduction rates of rotifers. By contrast, rotifers that fed on 100% P. globosa or on mixed diets had a longer lifespan than those fed on 100% Chlorella. The overall performances (combining reproduction and lifespan together) of rotifers cultured in 100% Chlorella or mixed diets were significantly higher than those cultured in 100% P. globosa. In general, Chlorella favors rotifers reproduction at the cost of shorter lifespan, whereas P. globosa tends to extend the lifespan of rotifers with lower fecundity, indicating that trade-off exists between reproduction and lifespan under different food conditions. The present study also suggests that rotifers may have the potential to control harmful P. globosa.

  13. Vectors of Leishmania braziliensis in the Petén, Guatemala.

    Science.gov (United States)

    Rowton, E; de Mata, M; Rizzo, N; Navin, T; Porter, C

    1991-12-01

    During a 1-year study, 13 species of sand fly were collected in bite-landing collections on human attractants in Tikal, Guatemala. Using isoenzyme analysis, Leishmania braziliensis was identified among isolates from Lutzomyia ovallesi, Lu. panamensis, and Lu. ylephiletor. Lutzomyia ovallesi, Lu. shannoni, and Lu. cruciata were found with flagellates whose isoenzyme patterns matched unidentified flagellates isolated from a patient with mucosal lesions.

  14. Meeting on the Microbiology of Soils, Autumn 2001: Estimation of protozoan diversity in soil

    DEFF Research Database (Denmark)

    Ekelund, Flemming

    2002-01-01

    Different methods of estimating protozoan diversity in soil are discussed in this paper, with the major emphasis on heterotrophic flagellates. Although many species of ciliates and testate amoebae seem to be unique to the soil environment, the communities of heterotrophic flagellates and naked am...

  15. Epidermal response of rainbow trout to Ichthyobodo necator

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Kuhn, Jesper Andreas; Mohammad, Rezkar Jaafar

    2014-01-01

    Infections with the parasitic flagellate Ichthyobodo necator (Henneguy, 1883) cause severe skin and gill disease in rainbow trout Oncorhynchus mykiss (Walbaum, 1792) juveniles. The epidermal disturbances including hyperplasia and mucous cell exhaustion caused by parasitization are known, but no d...

  16. Studies on the associates and parasites of zooplankton from southwest and southeast coasts of India

    Digital Repository Service at National Institute of Oceanography (India)

    Santhakumari, V.

    on copepods, ostracods and crab larvae. Two ectoparasitic flagellates were recorded from copepods, one from euphausiids and another from decapod larvae. One species of ciliate and a few trematod larvae were noticed in the body cavity of chaetognaths. Some...

  17. Fulltext PDF

    Indian Academy of Sciences (India)

    Unknown

    diversity and ecology. Teaching and research had ... The habitats have a longer life, show a succession of species and end up with flagellates or with ... nic continuity (like protoplasmic connections) between the neighbouring cells. Instead of ...

  18. Studies on the microzooplankton from the central and eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Gauns, M; Mohanraju, R.; Madhupratap, M

    Numerical abundance and composition of microzooplankton in the upper 200 m were studied from the central and eastern Arabian Sea during three seasons. Protozoans, comprising of ciliates (loricates and aloricates), flagellates and sarcodines were...

  19. An anaerobic mitochondrion that produces hydrogen

    NARCIS (Netherlands)

    Boxma, Brigitte; Graaf, Rob M. de; Staay, Georg W.M. van der; Alen, Theo A. van; Ricard, Guenola; Gabaldón, Toni; Hoek, Angela H.A.M. van; Moon-van der Staay, Seung Yeo; Koopman, Werner J.H.; Hellemond, Jaap J. van; Tielens, Aloysius G.M.; Friedrich, Thorsten; Veenhuis, Marten; Huynen, Martijn A.; Hackstein, Johannes H.P.

    2005-01-01

    Hydrogenosomes are organelles that produce ATP and hydrogen, and are found in various unrelated eukaryotes, such as anaerobic flagellates, chytridiomycete fungi and ciliates. Although all of these organelles generate hydrogen, the hydrogenosomes from these organisms are structurally and

  20. Epizoic and ectoparasitic protozoans from crab larvae

    Digital Repository Service at National Institute of Oceanography (India)

    Santhakumari, V.

    A suctorian, Ephelota gemmipara Hertwig, infesting the zoea of the peacrab, Porcellana and an ectoparasitic flagellate Ellobiopsis chattoni Caullery infecting the zoea of the crab were observed from off Cape Comorin, the south-east coast of India...

  1. Isolation of Leishmania braziliensis from Lutzomyia ovallesi (Diptera:Psychodidae) in Guatemala.

    Science.gov (United States)

    Rowton, E D; de Mata, M; Rizzo, N; Porter, C H; Navin, T R

    1992-04-01

    Leishmania braziliensis is endemic in Guatemala and Belize in Central America. To help identify the vector(s) of this parasite in Guatemala, phlebotomine sand flies that were aspirated from the clothing of collectors at Tikal National Park in the Department of the Peten were examined for flagellates. Lutzomyia ovallesi was found infected with flagellates that were identified as L. braziliensis by isoenzyme electrophoresis. The isoenzyme profile of this isolate matched those from humans from the same area.

  2. Efficiency of swimming of micro-organism and singularity in shape space

    OpenAIRE

    Kawamura, Masako

    1996-01-01

    Micro-organisms can be classified into three different types according to their size. We study the efficiency of the swimming of micro-organism in two dimensional fluid as a device for helping the explanation of this hierarchy in the size. We show that the efficiency of flagellate becomes unboundedly large, whereas that of ciliate has the upper bound. The unboundedness is related to the curious feature of the shape space, that is, a singularity at the basic shape of flagellate.

  3. Study of the distribution of Malassezia species in patients with pityriasis versicolor and healthy individuals in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Zeraati Hojjat

    2004-05-01

    Full Text Available Abstract Background Pityriasis versicolor is a superficial infection of the stratum corneum which caused by a group of yeasts formerly named pityrosporium. The taxonomy of these lipophilic yeasts has recently been modified and includes seven species referred as Malassezia. The aim of this study is to compare the distribution of Malassezia species isolated from pityriasis versicolor lesions and those isolated from healthy skins. Methods Differentiation of all malassezia species performed using morphological features and physiological test including catalase reaction, Tween assimilation test and splitting of esculin. Results In pityriasis versicolor lesions, the most frequently isolated species was M. globosa (53.3%, followed by M. furfur (25.3%, M. sympodialis(9.3%, M. obtusa (8.1% and M. slooffiae (4.0%. The most frequently isolated species in the skin of healthy individuals were M. globosa, M. sympodialis, M. furfur, M. sloofiae and M. restricta which respectively made up 41.7%, 25.0%, 23.3%, 6.7% and 3.3% of the isolated species. Conclusions According to our data, M. globosa was the most prevalent species in the skin of healthy individuals which recovered only in the yeast form. However, the Mycelial form of M. globosa was isolated as the dominant species from pityriasis versicolor lesions. Therefore, the role of predisposing factors in the conversion of this yeast to mycelium and its subsequent involvement in pityriasis versicolor pathogenicity should be considered.

  4. Study of the distribution of Malassezia species in patients with pityriasis versicolor and healthy individuals in Tertiary Care Hospital, Punjab

    Directory of Open Access Journals (Sweden)

    M Kaur

    2013-01-01

    Full Text Available Purpose: Pityriasis versicolor (PV is a chronic superficial fungal disease caused by Malassezia species. Our aim was to identify Malassezia species from PV patients and healthy individuals in Punjab. Materials and Methods: Modified Dixon agar was used as isolation culture medium. Identification was based on morphological observation and biochemical evaluation. The biochemical evaluation consisted of culture onto Sabouraud dextrose agar, catalase reaction, Tween assimilation, Cremophor EL assimilation, splitting of esculin and growth at 38 0 C. Results: Out of 58 microscopically diagnosed cases of PV, growth was obtained from 54 (93.10% cases. The most frequently isolated species were M. globosa, M. sympodialis and M. furfur which made up 51.79%, 31.42% and 18.51% of the isolated etiological agents respectively. However, the major isolate from the back of healthy individuals was M. sympodialis (47.61%, followed by M.obtusa (19.04%, M. globosa (14.20%, M. furfur (9.52%, M. pachydermatis (4.76% and M. slooffiae (4.76%. Conclusions: M. globosa in its mycelial phase was the main etiological agent, but as normal flora from the back of healthy subjects, it was found in significantly less number (P = 0.01, suggesting that the higher pathogenicity of M. globosa in terms of enzymatic endowment, might be the cause of its predominance in PV lesions.

  5. Phylogenetic analysis reveals a high prevalence of Sporothrix brasiliensis in Feline sporotrichosis outbreaks

    NARCIS (Netherlands)

    Rodrigues, A.M.; de Melo Teixeira, M.; de Hoog, G.S.; Pacheco Schubach, T.M.; Pereira, S.A.; Ferreira Fernandes, G.; Lopes Bezerra, L.M.; Felipe, M.S.; Pires de Camargo, Z.

    2013-01-01

    Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics

  6. Phylogenetic analysis reveals a high prevalence of Sporothrix brasiliensis in feline sporotrichosis outbreaks

    NARCIS (Netherlands)

    Rodrigues, A.M.; Teixeira, M.; de Hoog, G.S.; Schubach, T.M.P.; Pereira, S.A.; Fernandes, G.F.; Bezerra, L.M.; Felipe, M.S.; Camargo, Z.P.

    2013-01-01

    Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics

  7. Human sporotrichosis beyond the epidemic front reveals classical transmission types in Espírito Santo, Brazil

    NARCIS (Netherlands)

    de Araujo, Mariceli L; Rodrigues, Anderson M; Fernandes, Geisa F; de Camargo, Zoilo P; de Hoog, G Sybren

    Sporotrichosis has emerged as the main subcutaneous mycosis of humans and animals around the world. With particular differences in frequency, the major species includes Sporothrix brasiliensis, S. schenckii, S. globosa and S. luriei. In Brazil, the main aspect of this epidemic is based on the

  8. Comparative genomics of the major agents of human and animal Sporotrichosis: Sporothrix schenckii and Sporothrix brasiliensis

    NARCIS (Netherlands)

    Teixeira, M.M.; de Almeida, L.G.P.; Kubitschek-Barreira, P.; Alves, F.L.; Kioshima, E.S.; Abadio, A.K.R.; Fernandes, L.; Derengowski, L.S.; Ferreira, K.S.; Souza, R.C.; Ruiz, J.C.; de Andrade, N.C.; Paes, H.C.; Nicola, A.M.; Albuquerque, P.; Gerber, A.L.; Martins, V.P.; Peconick, L.D.F.; Neto, A.V.; Chaucanez, C.B.; Silva, P.A.; cunha, O.L.; de Oliveira, F.F.M.; dos Santos, T.C.; Barros, A.L.N.; Soares, M.A.; de Oliveira, L.M.; Marini, M.M.; Villalobos-Duno, H.; Cunha, M.M.L.; de Hoog, S.; da Silveira, J.F.; Henrissat, B.; Niño-Vega, G.A.; Cisalpino, P.S.; Mora-Montes, H.M.; Almeida, S.R.; Stajich, J.E.; Lopes-Bezerra, L.M.; Vasconcelos, A.T.R.; Felipe, M.S.S.

    2014-01-01

    Background: The fungal genus Sporothrix includes at least four human pathogenic species. One of these species, S. brasiliensis, is the causal agent of a major ongoing zoonotic outbreak of sporotrichosis in Brazil. Elsewhere, sapronoses are caused by S. schenckii and S. globosa. The major aims on

  9. The use of fuzzy logic for data analysis and modelling of European ...

    African Journals Online (AJOL)

    The use of fuzzy logic for data analysis and modelling of European harmful algal blooms: results of the HABES project. ... African Journal of Marine Science ... Alexandrium minutum, Karenia mikimotoi and Phaeocystis globosa at various European sites as part of the Harmful Algal Blooms Expert System (HABES) project.

  10. Colony Size of Phaeocystis Antarctica (Prymnesiophyceae) as Influenced by Zooplankton Grazers

    Science.gov (United States)

    The haptophyte Phaeocystis antarctica is a dominant phytoplankton species in the Ross Sea, Antarctica, and exists as solitary cells and mucilaginous colonies that differ by several orders of magnitude in size. Recent studies with P. globosa suggested that colony formation and enl...

  11. Phytoplankton Virus Production Negatively Affected by Iron Limitation

    NARCIS (Netherlands)

    Slagter, H.A.; Gerringa, L.J.A.; Brussaard, C.P.D.

    2016-01-01

    Fe-limited monocultures of the ubiquitous algae Micromonas pusilla and Phaeocystis globosa were infected with their respective viruses (MpV and PgV) to ascertain the effect of Fe-limitation on phytoplankton host-virus dynamics. The effect of the viral shunt on Fe concentrations and bioavailability

  12. Synergistic Effects of Different Food Species on Life-History Traits of Daphnia-Galeata

    NARCIS (Netherlands)

    Boersma, M.; Vijverberg, J.

    1995-01-01

    In this paper we describe the life history consequences of feeding Daphnia galeata with different food types in different concentrations. We fed the animals with four concentrations of two green algae Scenedesmus obliquus and Chlamydomonas globosa, given separately as well as in a 1:1 mixture.

  13. Marine snow microbial communities: scaling of abundances with aggregate size

    DEFF Research Database (Denmark)

    Kiørboe, Thomas

    2003-01-01

    Marine aggregates are inhabited by diverse microbial communities, and the concentration of attached microbes typically exceeds concentrations in the ambient water by orders of magnitude. An extension of the classical Lotka-Volterra model, which includes 3 trophic levels (bacteria, flagellates...... are controlled by flagellate grazing, while flagellate and ciliate populations are governed by colonization and detachment. The model also suggests that microbial populations are turned over rapidly (1 to 20 times d-1) due to continued colonization and detachment. The model overpredicts somewhat the scaling...... of microbial abundances with aggregate size observed in field-collected aggregates. This may be because it disregards the aggregation/disaggregation dynamics of aggregates, as well as interspecific interactions between bacteria....

  14. Protists from a sewage‐contaminated aquifer on cape cod, Massachusetts

    Science.gov (United States)

    Novarino, Gianfranco; Warren, Alan; Kinner, Nancy E.; Harvey, Ronald W.

    1994-01-01

    Several species of flagellates (genera Bodo, Cercomonas, Cryptaulax, Cyathomonas, Goniomonas, Spumella) have been identified in cultures from a plume of organic contamination (treated sewage effluent) within an aquifer on Cape Cod, Massachusetts. Amoebae and numerous unidentifiable 2‐ to 3‐μm flagellates have also been observed. As a rule, flagellates were associated with solid surfaces, or were capable of temporary surface attachment, corroborating earlier observations from in situ and column transport experiments suggesting that protists in the Massachusetts aquifer have a high propensity for association with sediment grain surfaces. Based on the fact that cultures from the uncontaminated part of the aquifer yielded only a few species of protists, it is hypothesized that the greater abundance and variety of food sources in the contaminant plume is capable of supporting a greater number of protistan species.

  15. In vitro anti-Malassezia activity and potential use in anti-dandruff formulation of Asparagus racemosus.

    Science.gov (United States)

    Onlom, C; Khanthawong, S; Waranuch, N; Ingkaninan, K

    2014-02-01

    Malassezia species are frequently associated with dandruff and seborrhoeic dermatitis. The study was conducted to evaluate anti-fungal activities of the extracts obtained from the roots of Asparagus racemosus Willd against Malassezia furfur and M. globosa. Asparagus racemosus roots were successively extracted with the series of solvents, that is, hexane, ethanol and water, and also a saponin-enriched fraction was prepared. The amounts of saponin (equivalent to shatavarin IV) in the extracts were determined using ELISA. The extracts were tested for anti-fungal activity by disc diffusion and broth microdilution methods. By disc diffusion, only the ethanolic and saponin-enriched extracts demonstrated anti-fungal activity against M. furfur and M. globosa at the concentration of 1 mg per disc whereas the extracts with other solvents were ineffective. Multiple concentrations using the broth microdilution method against M. furfur and M. globosa yielded minimum inhibitory concentrations (MICs) of 25 mg mL(-1) for the ethanolic extract but much higher potency for the saponin-enriched extract: MICs to 0.20 and 0.40 mg mL(-1) for M. furfur and M. globosa, respectively. These extracts showed no antagonist effect with the anti-fungal agents, ketoconazole and zinc pyrithione. These studies revealed the antifungal activity of A. racemosus roots extracts. Because A. racemosus is also anti-inflammatory agent, it has the potential use as an active ingredient in an anti-dandruff formulation. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  16. Swimming and feeding of mixotrophic biflagellates

    DEFF Research Database (Denmark)

    Dölger, Julia; Nielsen, Lasse Tor; Kiørboe, Thomas

    2017-01-01

    Many unicellular flagellates are mixotrophic and access resources through both photosynthesis and prey capture. Their fitness depends on those processes as well as on swimming and predator avoidance. How does the flagellar arrangement and beat pattern of the flagellate affect swimming speed...... with variable position next to a no-slip sphere. Utilizing the observations and the model we find that puller force arrangements favour feeding, whereas equatorial force arrangements favour fast and quiet swimming. We determine the capture rates of both passive and motile prey, and we show that the flow...

  17. Microfaunal primary succession on the volcanic island Surtsey

    DEFF Research Database (Denmark)

    Frederiksen, Helle B.; Kraglund, H. O.; Ekelund, F.

    2001-01-01

    and nematodes were absent and only amoebae and heterotrophic flagellates were found. Most of the protozoan populations we examined were unable to survive salinity levels corresponding to seawater. We therefore conclude that many of soil protozoa populations on Surtsey arrived to the island as airborne cysts...... with different vegetation types (unvegetated soil, soil with one or two plant species, and bird colony soil with a diverse vegetation). We recorded at least 16 nematode taxa and 13 flagellate taxa. Most of these were not reported in previous surveys from Surtsey. On the location with unvegetated soil, ciliates...

  18. Food web in biological wastewater treatment processes. Who eats whom?; La cadena trofica en los sistemas de depuracion biologicos Quien se come a quien?

    Energy Technology Data Exchange (ETDEWEB)

    Mas Aceves, M.

    2007-07-01

    The organic matter coming to the biological system is assimilated by bacteria and protozoa (flagellated and gymnamoebae mainly). The majority of ciliates, flagellates or gymnamoebae protozoa are bacteria predators (whether disperse, floc-forming or filamentous bacteria) and some of those protozoa are able to feed on other protozoa. Therefore, and due to the great variability of food target in protozoa communities, a wide variety of food strategies can be described. so, gain knowledge on protozoa feeding strategies allows a better understanding of food transference efficiency from one trophic stage to another, and therefore, increasing the knowledge of biological wastewater treatment systems. (Author) 32 refs.

  19. Are grazer-induced adaptations of bacterial abundance and morphology timedependent?

    Directory of Open Access Journals (Sweden)

    Gianluca CORNO

    2006-02-01

    Full Text Available Predation by protists is a well known force that shapes bacterial communities and can lead to filamentous forms and aggregations of large cell clusters. These classic resistance strategies were observed as a direct consequence of predation by heteroand mixotrophic flagellates (the main group of bacteria predators in water on natural assemblages of bacteria and on single plastic strains. Recently it was shown that a long time exposure (about 30 days of a bacterial strain, characterized by high degree of phenotypic plasticity, to flagellates, without direct predation, enhanced the formation of resistant forms (filaments in a continuous culture system. Target prey populations and predators were separated by a dialysis membrane. Moreover, the positive impact on bacterial growth, due to the chemical excretes released by flagellates was demonstrated for exudates of photosynthetic activity. The same positive impact may also be seen in response to exudates related to grazing. In this study, two short-term experiments (<100 hours were conducted to test for modifications in the morphology and productivity of three different bacterial strains that were induced by the presence of active predators, but without direct predation. The growth and morphological distribution of each of the selected strains was tested separately using batch cultures. Cultures were either enriched with carbon in the presence or absence of flagellate predators, or included pre-filtered exudates from flagellate activity. In a second experiment, bottles were provided with a central dialysis bag that contained active flagellates, and were inoculated with the selected bacterial strains. In this way, bacteria were exposed to the presence of predators without direct predation. The bacterial strains used in this experience were characterised by a high degree of phenotypic plasticity and exhibited different successful strategies of resistance against grazing. The flagellates selected as

  20. The regrowth of phytoplankton cultures after UV disinfection

    International Nuclear Information System (INIS)

    Martínez, Lucía F.; Mahamud, Manuel M.; Lavín, Antonio G.; Bueno, Julio L.

    2013-01-01

    Highlights: ► Phytoplankton cultures were placed in a rich medium after UV-C irradiation. ► Flow cytometry and PAM were used for determining cell viability. ► The behavior differs from that of cultures kept in their original environment. ► Chlorella autotrophica recovers between 5 and 10 days after the treatment. ► Phaeocystis globosa shows only a slight recovery for low-dose UV-radiation exposure. - Abstract: This study addresses how cultures of three phytoplankton species –Chaetoceros calcitrans, Chlorella autotrophica and Phaeocystis globosa – can recover from the effects of UV-C exposure if the cells are placed in a rich medium. Flow cytometry and pulse amplitude modulation (PAM) were used to determine cell recovery after UV treatment. The recovery of C. calcitrans was complete 9 days after treatment. For C. autotrophica, the recovery was noticeable 5 days after treatment. P. globosa only recovered if the UV dose did not exceed 7.3 × 10 5 μWs/cm 2 . The recovery of the UV-treated cultures introduced to a regrowth medium, compared with the recovery of the irradiated cultures kept in their original environment, had two main characteristics: cell recovery was slower but was more efficient. This pattern of recovery has very important implications for real ballast water management systems because such systems discharge treated water into the environment

  1. Application of rotifer Brachionus plicatilis in detecting the toxicity of harmful algae

    Science.gov (United States)

    Yan, Tian; Wang, Yunfeng; Wang, Liping; Chen, Yang; Han, Gang; Zhou, Mingjiang

    2009-05-01

    The toxicity of seven major HAB (harmful algal bloom) species/strains, Prorocentrum donghaiense, Phaeocystis globosa, Prorocentrum micans, Alexandrium tamarense (AT-6, non-PSP producer), Alexandrium lusitanicum, Alexandrum tamarense (ATHK) and Heterosigma akashiwo were studied against rotifer Brachionus plicatilis under laboratory conditions. The results show that P. donghaiense, P. globosa, P. micans, A. tamarense (AT-6), or A. lusitanicum could maintain the individual survival and reproduction, as well as the population increase of the rotifer, but the individual reproduction would decrease when exposed to these five algae at higher densities for nine days; H. akashiwo could decrease the individual survival and reproduction, as well as population increase of the rotifer, which is similar to that of the starvation group, indicating that starvation might be its one lethal factor except for the algal toxins; A. tamarense (ATHK) has strong lethal effect on the rotifer with 48h LC50 at 800 cells/mL. The experiment on ingestion ability indicated by gut pigment change shows that P. donghaiense, P. globosa, P. micans, A. tamarense (AT-6) and A. lusitanicum can be taken by the rotifers as food, but A. tamarense (ATHK) or H. akashiwo can be ingested by the rotifers. The results indicate that all the indexes of individual survival and reproduction, population increase, gut pigment change of the rotifers are good and convenient to be used to reflect the toxicities of HAB species. Therefore, rotifer is suggested as one of the toxicity testing organisms in detecting the toxicity of harmful algae.

  2. Interspecific competition and protistan grazing affect the coexistence of freshwater betaproteobacterial strains.

    Czech Academy of Sciences Publication Activity Database

    Salcher, Michaela M.; Ewert, C.; Šimek, Karel; Kasalický, Vojtěch; Posch, T.

    2016-01-01

    Roč. 92, č. 2 (2016), fiv156 ISSN 0168-6496 R&D Projects: GA ČR(CZ) GA13-00243S Institutional support: RVO:60077344 Keywords : betaproteobacteria * chemostat * co-cultivation * flagellate-selective bacterivory * interspecific competition * synergistic cooperation Subject RIV: EE - Microbiology, Virology Impact factor: 3.720, year: 2016

  3. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The prasinophytes (early diverging Chlorophyta), consisting of simple unicellular green algae, occupy a critical position at the base of the green algal tree of life, with some of its representatives viewed as the cell form most similar to the first green alga, the `ancestral green flagellate'. Relatively large-celled unicellular ...

  4. Competitive Advantage Provided by Bacterial Motility in the Formation of Nodules by Rhizobium meliloti

    Science.gov (United States)

    Ames, Peter; Bergman, Kostia

    1981-01-01

    The effect of motility on the competitive success of Rhizobium meliloti in nodule production was investigated. A motile strain formed more nodules than expected when mixed at various unfavorable ratios with either flagellated or nonflagellated nonmotile derivatives. We conclude that motility confers a selective advantage on rhizobia when competing with nonmotile strains. PMID:7298580

  5. The effect of the Banton 300 oil-spill accident on marine life in Umm ...

    African Journals Online (AJOL)

    ... sponges, acorn barnacles, copepods, echinoderms and fish); sub-lethal disruption of physiological and/or behavioural activities (bacterioplankton, heterotrophic flagellates, and tintinnid ciliates); effects of direct coating (birds and mangroves); incorporation of hydrocarbons in organisms (crabs, scallops, edible mussels, ...

  6. Phytoplankton diversity in the Cross River Estuary of Nigeria | Ekwu ...

    African Journals Online (AJOL)

    Bacillariophyceae (Diatom) was the most abundant phytoplankton family, constituting 71.58% of total Algal density, followed by Chlorophyceae (Green algae) with 13.84%, Cyanobacteria (Blue-green algae) with 12.69%, while Euglenophyceae (Green flagellates) and Dinophyceae (Dinoflagellates) recorded 0.88% and ...

  7. Molecular identification of Giardia lamblia isolates from adult human ...

    African Journals Online (AJOL)

    ARL

    2013-02-27

    Feb 27, 2013 ... Giardia lamblia is a flagellated protozoa that infects the intestinal tract of a wide range of mammalian hosts, including both wild and domestic animals as well as humans. Two genotypes A and B are commonly reported among humans. The purpose of this study was to investigate the genotypes of G.

  8. Detection, typing and control of Histomonas meleagridis

    NARCIS (Netherlands)

    van der Heijden, H.M.J.F.

    2009-01-01

    Histomonosis (blackhead) is a disease of galliform birds caused by the flagellated protozoan Histomonas meleagridis. Its primary target organs are the ceca and the liver. Especially in turkeys, mortality can be very high (up to 100%). In the 1960’s and 1970’s several effective antihistomonal

  9. Phylogenomic analysis of kinetoplastids supports that trypanosomatids arose from within bodonids

    DEFF Research Database (Denmark)

    Deschamps, Philippe; Lara, Enrique; Marande, William

    2011-01-01

    Kinetoplastids are a large group of free-living and parasitic eukaryotic flagellates, including the medically important trypanosomatids (e.g., Trypanosoma and Leishmania) and the widespread free-living and parasitic bodonids. Small subunit rRNA- and conserved protein-based phylogenies support...

  10. Cooperative motion of intrinsic and actuated semiflexible swimmers

    NARCIS (Netherlands)

    Llopis, I.; Pagonabarraga, I.; Lagomarsino, M.C.; Lowe, C.P.

    2013-01-01

    We examine the phenomenon of hydrodynamic-induced cooperativity for pairs of flagellated micro-organism swimmers, of which spermatozoa cells are an example. We consider semiflexible swimmers, where inextensible filaments are driven by an internal intrinsic force and torque-free mechanism (intrinsic

  11. Effectiveness of copper sulfate, potassium permanganate, and peracetic acid to reduce mortality and infestation of Ichthyobodo nector in channel catfish Ictalurus punctatus (Rafinesque 1818)

    Science.gov (United States)

    Ichthyobodo necator is a single celled bi-flagellate parasite, and in high density can causes significant mortality in young fish. Copper sulfate (CuSO4), potassium permanganate (KMnO4) and peracetic acid (PAA) were evaluated for effectiveness against ichthyobodosis. Treatments were: untreated con...

  12. JPRS Report, East Europe

    Science.gov (United States)

    1991-07-11

    psychological Czechoslovakism as 12 CZECHOSLOVAKIA JPRS-EER-91-103 11 July 1991 well as cosmopolitism . But it was not this source form which emanated...overcoming the breakdown of national self-confidence accompanied by cheap cosmopolitism and needless national self-flagellation. But if the socioeconomic

  13. Evaluation of fatty acids as biomarkers for a natural plankton community. A field study of a spring bloom and a post-bloom period off West Greenland

    DEFF Research Database (Denmark)

    Reuss, N.; Poulsen, Louise K.

    2002-01-01

    community were taken at the depth of fluorescence maximum. High biomass and diatom dominance during the spring bloom and low biomass and flagellate dominance in the post-bloom period were reflected by the fatty acid profiles. The total amount of fatty acid ranged from 55 to 132 mug 1(-1) during the spring...

  14. Control of plankton seasonal succession by adaptive grazing

    DEFF Research Database (Denmark)

    Mariani, Patrizio; Andersen, Ken Haste; Visser, Andre

    2013-01-01

    The ecological succession of phytoplankton communities in temperate seas is characterized by the dominance of nonmotile diatoms during spring and motile flagellates during summer, a pattern often linked to the seasonal variation in the physical environment and nutrient availability. We focus...

  15. Discolouration of water and its effect on fisheries along the Goa Coast

    Digital Repository Service at National Institute of Oceanography (India)

    Devassy, V.P.; Nair, S.R.S.

    chlorophyll a concentration was as high as 16.70 mg m-3 and N. miliaris contributed to 91.3% of the total phytoplankton (51,360 counts 1-1). The bloom imparted green colouration due to the presence of a flagellate Pedinomonas noctilucae (Subr.) Sweeney...

  16. Trophic level stability-inducing effects of predaceous early juvenile fish in an estuarine mesocosm study.

    Directory of Open Access Journals (Sweden)

    Ryan J Wasserman

    Full Text Available Classically, estuarine planktonic research has focussed largely on the physico-chemical drivers of community assemblages leaving a paucity of information on important biological interactions.Within the context of trophic cascades, various treatments using in situ mesocosms were established in a closed estuary to highlight the importance of predation in stabilizing estuarine plankton abundances. Through either the removal (filtration or addition of certain planktonic groups, five different trophic systems were established. These treatments contained varied numbers of trophic levels and thus different "predators" at the top of the food chain. The abundances of zooplankton (copepod and polychaete, ciliate, micro-flagellate, nano-flagellate and bacteria were investigated in each treatment, over time. The reference treatment containing apex zooplanktivores (early juvenile mullet and plankton at natural densities mimicked a natural, stable state of an estuary. Proportional variability (PV and coefficient of variation (CV of temporal abundances were calculated for each taxon and showed that apex predators in this experimental ecosystem, when compared to the other systems, induced stability. The presence of these predators therefore had consequences for multiple trophic levels, consistent with trophic cascade theory.PV and CV proved useful indices for comparing stability. Apex predators exerted a stabilizing pressure through feeding on copepods and polychaetes which cascaded through the ciliates, micro-flagellates, nano-flagellates and bacteria. When compared with treatments without apex predators, the role of predation in structuring planktonic communities in closed estuaries was highlighted.

  17. Protozoan Diversity in a productive fishpond of a tropical plateau ...

    African Journals Online (AJOL)

    A survey of the Protozoan species diversity in a productive fishpond of the Jos Plateau, Nigeria was investigated at 7 day interval over a period of 11 months. Samples were collected from water column and sediment. Protozoans were found to compose of the flagellates sarcodines and cilliates. There was a significant ...

  18. The revised classification of eukaryotes

    Czech Academy of Sciences Publication Activity Database

    Adl, S.; Simpson, A. G. B.; Lane, C. E.; Lukeš, Julius; Bass, D.; Bowser, S. S.; Brown, M W.; Burki, F.; Dunthorn, M.; Hampl, V.; Heiss, A.; Hoppenrath, M.; Lara, E.; Gall, L. L.; Lynn, D. H.; McManus, H.; Mitchell, E. A. D.; Mozley-Stanridge, S. E.; Parfrey, L. W.; Pawlowski, J.; Rueckert, S.; Shadwick, L.; Schoch, C.L.; Smirnov, A.; Spiegel, F. W.

    2012-01-01

    Roč. 59, č. 5 (2012), s. 429-514 ISSN 1066-5234 Institutional support: RVO:60077344 Keywords : Algae * amoebae * biodiversity * ciliates * flagellates * fungi * parasites * protozoa * systematics * taxonomy Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.162, year: 2012 http://onlinelibrary.wiley.com/doi/10.1111/j.1550-7408.2012.00644.x/pdf

  19. Molecular comparison of cultivable protozoa from a pristine and a polycyclic aromatic hydrocarbon polluted site

    DEFF Research Database (Denmark)

    Lara, E; Berney, C; Ekelund, Flemming

    2007-01-01

    We compared the abundance and diversity of cultivable protozoa (flagellates and amoebae) in a polycyclic aromatic hydrocarbon (PAH) polluted soil and an unpolluted control, by isolating and cultivating clonal strains. The number of cultivable protozoa was higher in the polluted soil; however...

  20. Reconstructing the early evolution of the fungi using a six gene phylogeny

    NARCIS (Netherlands)

    James, T.Y.; Kauff, F.; Schoch, C.L.; Matheny, P.B.; Hofstetter, V.; Cox, C.J.; Celio, G.; Gueidan, C.; Fraker, E.; Miadlikowska, J.; Lumbsch, H.T.; Rauhut, A.; Reeb, V.; Arnold, A.E.; Amtoft, A.; Stajich, J.E.; Hosaka, K.; Sung, G.H.; Johnson, D.; O'Rourke, B.; Binder, M.; Curtis, J.M.; Slot, J.C.; Wang, Z.; Wilson, A.W.; Schüßler, A.; Longcore, J.E.; O'Donnell, K.; Mozley-Standridge, S.; Porter, D.; Letcher, P.M.; Powell, M.J.; Taylor, J.W.; White, M.M.; Griffith, G.W.; Davies, D.R.; Sugiyama, J.; Rossman, A.Y.; Rogers, J.D.; Pfister, D.H.; Hewitt, D.; Hansen, K.; Hambleton, S.; Shoemaker, R.A.; Kohlmeyer, J.; Volkmann-Kohlmeyer, B.; Spotts, R.A.; Serdani, M.; Crous, P.W.; Hughes, K.W.; Matsuura, K.; Langer, E.; Langer, G.; Untereiner, W.A.; Lücking, R.; Büdel, B.; Geiser, D.M.; Aptroot, A.; Diederich, P.; Schmitt, I.; Schultz, M.; Yahr, R.; Hibbett, D.S.; Lutzoni, F.; McLaughlin, D.J.; Spatafora, J.W.; Vilgalys, R.

    2006-01-01

    The ancestors of fungi are believed to be simple aquatic forms with flagellated spores, similar to members of the extant phylum Chytridiomycota (chytrids). Current classifications assume that chytrids form an early-diverging clade within the kingdom Fungi and imply a single loss of the spore

  1. Single and concomitant experimental infectionsby Endotrypanum spp. and Leishmania (Viannia guyanensis (Kinetoplastida: Trypanosomatidae in the Neotropical sand fly Lutzomyia longipalpis (Diptera: Psychodidae

    Directory of Open Access Journals (Sweden)

    André F Barbosa

    2006-12-01

    Full Text Available Lutzomyia longipalpis females received single and mixed infections with Endotrypanum and Leishmania. Two biological parameters were analyzed: the percentage of infected females and the distribution of flagellates in the gut of the females. The principal comparisons were performed between (1 two strains of Endotrypanum, (2 cloned versus primary sample of one strain of Endotrypanum, (3 Endotrypanum versus Leishmania guyanensis, and (4 the pattern of flagellates behaviour by optical microscopy in females with single or mixed infection versus the identification of parasites isolated from digestive tracts by isoenzyme electrophoresis. Flagellates of Endotrypanum showed distinct patterns of infection suggesting that there is variation between and within strains. The distribution of Endotrypanum and L. guyanensis differed significantly in relation to the colonization of the stomodeal valve. In co-infection with L. guyanensis, a large number of flagellates were seen to be plentifully infecting the stomodeal valve in significantly more specimens than in females infected by Endotrypanum only. However, the electrophoretic profiles of isoenzymes of parasites recovered from all co-infected specimens corresponded to Endotrypanum. This suggests that the mere correlation sand fly infection-biochemical analysis of isolates may induce parasitological incorrect consideration.

  2. Escape of protists in predator-generated feeding currents

    DEFF Research Database (Denmark)

    Jakobsen, Hans Henrik

    2002-01-01

    The ciliate Strobilidium sp. and 2 flagellates, Chrysochromulina simplex and Gymnodinium sp., were exposed to predator-generated feeding currents, and their escape responses were quantified using 2- and 3-dimensional video techniques. All 3 studied organisms responded by escaping at a defined dis...

  3. Phytoplankton absorption and pigment adaptation of a red tide in the ...

    African Journals Online (AJOL)

    Phytoplankton absorption and pigment characteristics of a red tide were investigated in coastal waters of the southern Benguela. Diagnostic indices indicated that dinoflagellates were the dominant phytoplankton group, with diatoms and small flagellates being of secondary importance. Very high biomass was observed ...

  4. Mucocutaneous leishmaniasis in an 11-year-old girl with ataxia ...

    African Journals Online (AJOL)

    LETTER TO THE EDITOR. Mucocutaneous leishmaniasis in an 11-year-old girl with ataxia telangectasia Бcase report. Leishmaniasis is a protozoal disease caused by flagellates of the genus Leishmania and transmit- ted by sand fly. The reservoir hosts are humans, dogs, and rodents. It has three different morphological.

  5. RuBisCO in Non-Photosynthetic Alga Euglena longa: Divergent Features, Transcriptomic Analysis and Regulation of Complex Formation

    Czech Academy of Sciences Publication Activity Database

    Záhonová, K.; Füssy, Z.; Oborník, Miroslav; Eliáš, M.; Yurchenko, V.

    2016-01-01

    Roč. 11, č. 7 (2016), e0158790 E-ISSN 1932-6203 Institutional support: RVO:61388971 Keywords : FLAGELLATE ASTASIA-LONGA * OXYGENASE SMALL SUBUNIT * A/B-BINDING-PROTEIN Subject RIV: EE - Microbiology, Virology Impact factor: 2.806, year: 2016

  6. Net heterotrophy in Faroe Islands clear-water lakes: causes and consequences for bacterioplankton and phytoplankton

    DEFF Research Database (Denmark)

    Pålsson, C.; Kritzberg, E. S.; Christoffersen, K.

    2005-01-01

    conditions and hence low primary production in combination with an input of allochthonous C with a relatively high availability. 4. Mixotrophic phytoplankton (Cryptomonas spp., Dinobryon spp. and flagellates cf. Ochromonas spp.) constituted a large percentage of the plankton community (17-83%), possibly...

  7. Centipeda periodontii in human periodontitis

    NARCIS (Netherlands)

    Rams, Thomas E.; Hawley, Charles E.; Whitaker, Eugene J.; Degener, John E.; van Winkelhoff, Arie J.

    This study assessed the subgingival occurrence of the flagellated, Gram-negative, anaerobic rod Centipeda periodontii in chronic periodontitis and periodontal health/gingivitis with species-specific nucleic acid probes, and evaluated the in vitro resistance of subgingival isolates to therapeutic

  8. A revision of Spondias L. (Anacardiaceae in the Neotropics

    Directory of Open Access Journals (Sweden)

    John D. Mitchell

    2015-08-01

    Full Text Available As part of an ongoing study of Anacardiaceae subfamily Spondioideae, the ten native and one introduced species of Spondias in the Neotropics are revised. The genus is circumscribed. Three new species, S. admirabilis, S. expeditionaria, and S. globosa, are described and illustrated; a key to the taxa found in the Neotropics and distribution maps are provided. The Paleotropical species and allied genera are reviewed. Diagnostic character sets include leaf architecture, habit, flower morphology, and gross fruit morphology. Notes on the ecology and economic botany of the species are provided.

  9. Antiviral and cytotoxic activities of some Indonesian plants.

    Science.gov (United States)

    Lohézic-Le Dévéhat, F; Bakhtiar, A; Bézivin, C; Amoros, M; Boustie, J

    2002-08-01

    Ten methanolic extracts from eight Indonesian medicinal plants were phytochemically screened and evaluated for antiviral (HSV-1 and Poliovirus) and cytotoxic activities on murine and human cancer lines (3LL, L1210, K562, U251, DU145, MCF-7). Besides Melastoma malabathricum (Melastomataceae), the Indonesian Loranthaceae species among which Elytranthe tubaeflora, E. maingayi, E. globosa and Scurrula ferruginea exhibited attractive antiviral and cytotoxic activities. Piper aduncum (Piperaceae) was found active on Poliovirus. S. ferruginea was selected for further studies because of its activity on the U251 glioblastoma cells.

  10. Sporothrix brasiliensis produces the highest levels of oxidative stress in a murine model among the species of the Sporothrix schenckii complex

    Directory of Open Access Journals (Sweden)

    Débora Nunes Mario

    Full Text Available Abstract INTRODUCTION: We compared indicators of oxidative stress in the tissue of mice infected with strains from Sporothrix schenckii complex. METHODS: Mice were inoculated with Sporothrix brasiliensis, Sporothrix schenckii sensu stricto, Sporothrix globosa, Sporothrix mexicana or Sporothrix albicans. The activity of catalase and glutathione were accessed in the liver and spleen. RESULTS: Animals infected with S. brasiliensis exhibited splenomegaly and significant decrease in catalase activity, and protein and non-protein thiol content compared to animals infected with the other species. CONCLUSIONS: Sporothrix brasiliensis exhibits higher pathogenicity compared to other species of the Sporothrix schenckii complex by increasing oxidative stress in animal tissue.

  11. Ethnomedicines used in Trinidad and Tobago for urinary problems and diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Lans Cheryl A

    2006-10-01

    Full Text Available Abstract Background This paper is based on ethnobotanical interviews conducted from 1996–2000 in Trinidad and Tobago with thirty male and female respondents. Methods A non-experimental validation was conducted on the plants used for urinary problems and diabetes mellitus: This is a preliminary step to establish that the plants used are safe or effective, to help direct clinical trials, and to inform Caribbean physicians of the plants' known properties to avoid counter-prescribing. Results The following plants are used to treat diabetes: Antigonon leptopus, Bidens alba, Bidens pilosa, Bixa orellana, Bontia daphnoides, Carica papaya, Catharanthus roseus, Cocos nucifera, Gomphrena globosa, Laportea aestuans, Momordica charantia, Morus alba, Phyllanthus urinaria and Spiranthes acaulis. Apium graviolens is used as a heart tonic and for low blood pressure. Bixa orellana, Bontia daphnoides, Cuscuta americana and Gomphrena globosa are used for jaundice. The following plants are used for hypertension: Aloe vera, Annona muricata, Artocarpus altilis, Bixa orellana, Bidens alba, Bidens pilosa, Bonta daphnoides, Carica papaya, Cecropia peltata, Citrus paradisi, Cola nitida, Crescentia cujete, Gomphrena globosa, Hibiscus sabdariffa, Kalanchoe pinnata, Morus alba, Nopalea cochinellifera, Ocimum campechianum, Passiflora quadrangularis, Persea americana and Tamarindus indicus. The plants used for kidney problems are Theobroma cacao, Chamaesyce hirta, Flemingia strobilifera, Peperomia rotundifolia, Petiveria alliacea, Nopalea cochinellifera, Apium graveolens, Cynodon dactylon, Eleusine indica, Gomphrena globosa, Pityrogramma calomelanos and Vetiveria zizanioides. Plants are also used for gall stones and for cooling. Conclusion Chamaesyce hirta, Cissus verticillata, Kalanchoe pinnata, Peperomia spp., Portulaca oleraceae, Scoparia dulcis, and Zea mays have sufficient evidence to support their traditional use for urinary problems, "cooling" and high cholesterol

  12. Ethnomedicines used in Trinidad and Tobago for urinary problems and diabetes mellitus

    Science.gov (United States)

    Lans, Cheryl A

    2006-01-01

    Background This paper is based on ethnobotanical interviews conducted from 1996–2000 in Trinidad and Tobago with thirty male and female respondents. Methods A non-experimental validation was conducted on the plants used for urinary problems and diabetes mellitus: This is a preliminary step to establish that the plants used are safe or effective, to help direct clinical trials, and to inform Caribbean physicians of the plants' known properties to avoid counter-prescribing. Results The following plants are used to treat diabetes: Antigonon leptopus, Bidens alba, Bidens pilosa, Bixa orellana, Bontia daphnoides, Carica papaya, Catharanthus roseus, Cocos nucifera, Gomphrena globosa, Laportea aestuans, Momordica charantia, Morus alba, Phyllanthus urinaria and Spiranthes acaulis. Apium graviolens is used as a heart tonic and for low blood pressure. Bixa orellana, Bontia daphnoides, Cuscuta americana and Gomphrena globosa are used for jaundice. The following plants are used for hypertension: Aloe vera, Annona muricata, Artocarpus altilis, Bixa orellana, Bidens alba, Bidens pilosa, Bonta daphnoides, Carica papaya, Cecropia peltata, Citrus paradisi, Cola nitida, Crescentia cujete, Gomphrena globosa, Hibiscus sabdariffa, Kalanchoe pinnata, Morus alba, Nopalea cochinellifera, Ocimum campechianum, Passiflora quadrangularis, Persea americana and Tamarindus indicus. The plants used for kidney problems are Theobroma cacao, Chamaesyce hirta, Flemingia strobilifera, Peperomia rotundifolia, Petiveria alliacea, Nopalea cochinellifera, Apium graveolens, Cynodon dactylon, Eleusine indica, Gomphrena globosa, Pityrogramma calomelanos and Vetiveria zizanioides. Plants are also used for gall stones and for cooling. Conclusion Chamaesyce hirta, Cissus verticillata, Kalanchoe pinnata, Peperomia spp., Portulaca oleraceae, Scoparia dulcis, and Zea mays have sufficient evidence to support their traditional use for urinary problems, "cooling" and high cholesterol. Eggplant extract as a

  13. Ethnomedicines used in Trinidad and Tobago for urinary problems and diabetes mellitus.

    Science.gov (United States)

    Lans, Cheryl A

    2006-10-13

    This paper is based on ethnobotanical interviews conducted from 1996-2000 in Trinidad and Tobago with thirty male and female respondents. A non-experimental validation was conducted on the plants used for urinary problems and diabetes mellitus: This is a preliminary step to establish that the plants used are safe or effective, to help direct clinical trials, and to inform Caribbean physicians of the plants' known properties to avoid counter-prescribing. The following plants are used to treat diabetes: Antigonon leptopus, Bidens alba, Bidens pilosa, Bixa orellana, Bontia daphnoides, Carica papaya, Catharanthus roseus, Cocos nucifera, Gomphrena globosa, Laportea aestuans, Momordica charantia, Morus alba, Phyllanthus urinaria and Spiranthes acaulis. Apium graviolens is used as a heart tonic and for low blood pressure. Bixa orellana, Bontia daphnoides, Cuscuta americana and Gomphrena globosa are used for jaundice. The following plants are used for hypertension: Aloe vera, Annona muricata, Artocarpus altilis, Bixa orellana, Bidens alba, Bidens pilosa, Bonta daphnoides, Carica papaya, Cecropia peltata, Citrus paradisi, Cola nitida, Crescentia cujete, Gomphrena globosa, Hibiscus sabdariffa, Kalanchoe pinnata, Morus alba, Nopalea cochinellifera, Ocimum campechianum, Passiflora quadrangularis, Persea americana and Tamarindus indicus. The plants used for kidney problems are Theobroma cacao, Chamaesyce hirta, Flemingia strobilifera, Peperomia rotundifolia, Petiveria alliacea, Nopalea cochinellifera, Apium graveolens, Cynodon dactylon, Eleusine indica, Gomphrena globosa, Pityrogramma calomelanos and Vetiveria zizanioides. Plants are also used for gall stones and for cooling. Chamaesyce hirta, Cissus verticillata, Kalanchoe pinnata, Peperomia spp., Portulaca oleraceae, Scoparia dulcis, and Zea mays have sufficient evidence to support their traditional use for urinary problems, "cooling" and high cholesterol. Eggplant extract as a hypocholesterolemic agent has some support but

  14. AVALIAÇÃO DA ATIVIDADE ANTIINFLAMATÓRIA DA FRAÇÃO ALCALOÍDICA DO FRUTO DE Solanum lycocarpum A.St.-Hil. (LOBEIRA)

    OpenAIRE

    VIEIRA JÚNIOR, Geraldo

    2004-01-01

    Solanum lycocarpum A. St.-Hil., popularmente conhecida como lobeira, é facilmente encontrada no cerrado. Caracteriza-se como uma planta arbustiva com até cinco metros de altura, ramos frágeis, apresentando fruto tipo baga globosa, de oito a quinze centímetros de diâmetro, cor verde-amarelada mesmo quando maduro, polpa carnosa e suculenta. A lobeira é usada na medicina popular para diversos fins terapêuticos, como por exemplo, bronquite, verminose, diabete e úlcera. Estudo co...

  15. Life-cycle modification in open oceans accounts for genome variability in a cosmopolitan phytoplankton.

    Science.gov (United States)

    von Dassow, Peter; John, Uwe; Ogata, Hiroyuki; Probert, Ian; Bendif, El Mahdi; Kegel, Jessica U; Audic, Stéphane; Wincker, Patrick; Da Silva, Corinne; Claverie, Jean-Michel; Doney, Scott; Glover, David M; Flores, Daniella Mella; Herrera, Yeritza; Lescot, Magali; Garet-Delmas, Marie-José; de Vargas, Colomban

    2015-06-01

    Emiliania huxleyi is the most abundant calcifying plankton in modern oceans with substantial intraspecific genome variability and a biphasic life cycle involving sexual alternation between calcified 2N and flagellated 1N cells. We show that high genome content variability in Emiliania relates to erosion of 1N-specific genes and loss of the ability to form flagellated cells. Analysis of 185 E. huxleyi strains isolated from world oceans suggests that loss of flagella occurred independently in lineages inhabiting oligotrophic open oceans over short evolutionary timescales. This environmentally linked physiogenomic change suggests life cycling is not advantageous in very large/diluted populations experiencing low biotic pressure and low ecological variability. Gene loss did not appear to reflect pressure for genome streamlining in oligotrophic oceans as previously observed in picoplankton. Life-cycle modifications might be common in plankton and cause major functional variability to be hidden from traditional taxonomic or molecular markers.

  16. Noncontact Cohesive Swimming of Bacteria in Two-Dimensional Liquid Films.

    Science.gov (United States)

    Li, Ye; Zhai, He; Sanchez, Sandra; Kearns, Daniel B; Wu, Yilin

    2017-07-07

    Bacterial swimming in confined two-dimensional environments is ubiquitous in nature and in clinical settings. Characterizing individual interactions between swimming bacteria in 2D confinement will help to understand diverse microbial processes, such as bacterial swarming and biofilm formation. Here we report a novel motion pattern displayed by flagellated bacteria in 2D confinement: When two nearby cells align their moving directions, they tend to engage in cohesive swimming without direct cell body contact, as a result of hydrodynamic interaction but not flagellar intertwining. We further found that cells in cohesive swimming move with higher directional persistence, which can increase the effective diffusivity of cells by ∼3 times as predicted by computational modeling. As a conserved behavior for peritrichously flagellated bacteria, cohesive swimming in 2D confinement may be key to collective motion and self-organization in bacterial swarms; it may also promote bacterial dispersal in unsaturated soils and in interstitial space during infections.

  17. Ultrastructure and molecular phylogenetic position of a novel phagotrophic stramenopile from low oxygen environments: Rictus lutensis gen. et sp. nov. (Bicosoecida, incertae sedis).

    Science.gov (United States)

    Yubuki, Naoji; Leander, Brian S; Silberman, Jeffrey D

    2010-04-01

    A novel free free-living phagotrophic flagellate, Rictus lutensis gen. et sp. nov., with two heterodynamic flagella, a permanent cytostome and a cytopharynx was isolated from muddy, low oxygen coastal sediments in Cape Cod, MA, USA. We cultivated and characterized this flagellate with transmission electron microscopy, scanning electron microscopy and molecular phylogenetic analyses inferred from small subunit (SSU) rDNA sequences. These data demonstrated that this organism has the key ultrastructural characters of the Bicosoecida, including similar transitional zones and a similar overall flagellar apparatus consisting of an x fiber and an L-shape microtubular root 2 involved in food capture. Although the molecular phylogenetic analyses were concordant with the ultrastructural data in placing R. lutensis with the bicosoecid clade, the internal position of this relatively divergent sequence within the clade was not resolved. Therefore, we interpret R. lutensis gen. et sp. nov. as a novel bicosoecid incertae sedis. Copyright 2009 Elsevier GmbH. All rights reserved.

  18. Survival and Virulence of Campylobacter spp. in the Environment

    DEFF Research Database (Denmark)

    Bui, Thanh Xuan

    of environmental stress factors, namely heat shock, starvation, osmosis, and oxidation, on the expression of three virulence genes (ciaB, dnaJ, and htrA) of C. jejuni and its uptake by and intracellular survival within A. castellanii. I also investigated the mechanism(s) involved in phagocytosis and killing of C....... jejuni by A. castellanii. I observed that heat and osmotic stresses reduced the survival of C. jejuni significantly, whereas oxidative stress had no effect. The results of qRT-PCR experiments showed that the transcription of virulence genes of C. jejuni was slightly up-regulated under heat and oxidative...... soil flagellates may play a role for the survival of these food-borne pathogens on plant surfaces and in soil. It would be very interesting to further investigate the impacts of this soil flagellate on the survival of different food-borne pathogens in soil and in plant surface that may explain...

  19. Identification and phylogenetic analysis of heme synthesis genes in trypanosomatids and their bacterial endosymbionts.

    Directory of Open Access Journals (Sweden)

    João M P Alves

    Full Text Available It has been known for decades that some insect-infecting trypanosomatids can survive in culture without heme supplementation while others cannot, and that this capability is associated with the presence of a betaproteobacterial endosymbiont in the flagellate's cytoplasm. However, the specific mechanisms involved in this process remained obscure. In this work, we sequence and phylogenetically analyze the heme pathway genes from the symbionts and from their hosts, as well as from a number of heme synthesis-deficient Kinetoplastida. Our results show that the enzymes responsible for synthesis of heme are encoded on the symbiont genomes and produced in close cooperation with the flagellate host. Our evidence suggests that this synergistic relationship is the end result of a history of extensive gene loss and multiple lateral gene transfer events in different branches of the phylogeny of the Trypanosomatidae.

  20. The impact of the fungicide fenpropimorph (Corbel) on bacterivorous and fungivorous protozoa in soil

    DEFF Research Database (Denmark)

    Ekelund, Flemming

    1999-01-01

    1. The ability of indigenous soil protozoa to survive and multiply when exposed to various concentrations of the fungicide fenpropimorph was investigated. The number of protozoan taxa in relation to biocide concentration was examined in enrichment cultures. The population dynamics of bacterivorous...... and fungivorous protozoa, hyphal forming units, and respiration activity were followed in soil microcosms amended with glucose and various concentrations of fenpropimorph. 2. The average number of flagellate taxa detected in 50-mg portions of air-dried soil declined from 12 to zero with fenpropimorph...... as in systems with glucose only; however, soil respiration was significantly impeded in microcosm systems with a low pesticide content and stimulated in systems with a high pesticide content. 4. Bacterivorous protozoa (naked amoebae and heterotrophic flagellates) were affected at all tested concentrations (074...

  1. Biomass reallocation within freshwater bacterioplankton induced by manipulating phosphorus availability and grazing

    Czech Academy of Sciences Publication Activity Database

    Posch, T.; Mindl, B.; Horňák, Karel; Jezbera, Jan; Salcher, M.M.; Sattler, B.; Sonntag, B.; Vrba, Jaroslav; Šimek, Karel

    2007-01-01

    Roč. 49, č. 3 (2007), s. 223-232 ISSN 0948-3055 R&D Projects: GA ČR(CZ) GA206/05/0007 Grant - others:ASF(AT) FWF P17554-B06 Institutional research plan: CEZ:AV0Z60170517 Keywords : bacterial biomass * bacteria-flagellate interactions * fluorescence in situ hybridization Subject RIV: EH - Ecology, Behaviour Impact factor: 2.385, year: 2007

  2. Dicty_cDB: Contig-U14801-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CAZO Naegleria gruberi Flagellate Sta... 42 1.1 2 ( FD681213 ) CBHW4480.rev CBHW Mycosphaerella fiji...ensis MfEST4... 46 1.9 1 ( FD669540 ) CBHT4023.rev CBHT Mycosphaerella fijiensis MfEST3...... 46 1.9 1 ( FD669082 ) CBHT3400.rev CBHT Mycosphaerella fijiensis MfEST3... 46 1.9 1 ( AE017194 ) Bacillus

  3. Effect of temperature on degradation of musty odour compound producing by cyanobacteria, Phormidium tenue by microflagellate, Monas guttula; Benmochu Monas guttula ni yoru kabishu sansei sorui Phormidium tenue no bunkai ni oyobosu ondo no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B.; Sudo, R. [Tohoku University, Sendai (Japan). Faculty of Engineering; Sugiura, N. [Ibaraki Prefectural Waterworks, Ibaraki (Japan); Inamori, Y.; Nishimura, O. [National Inst. for Environmental Studies, Tsukuba (Japan); Higashi, T. [University of Tsukuba, Tsukuba (Japan). Institute of Applied Biochemical

    1998-04-10

    Biodegradation characteristics of cyanobacteria, Phormidium tenue and its metabolites, 2-methylisoborneol (MIB) by protozoan microflagellate, Monas guttula, and the effect of temperature on them were examined in batch culture experiment. The flagellate was found to predate on P. tenue favorably as a food source within a wide temperature range from 10degC to 30degC. Specific growth rate ({mu}) and generation time (t{sub d}) of the flagellate were 4.6 day{sup -1} and 3.5 h{sup -1}, respectively at 20degC and 30degC, whereas in the case of 10degC the lag values of {mu} and t{sub d} were obtained by 1.9 fold in comparison with the removal ratio of 61% at the first cultivation day and that of 99% at the 2nd day at 30degC, while at 20degC the removal was only about 30% in the first day, but P. tenue could be perfectly reduced at the 2nd day. Although the reduction rate of the P. tenue was slow at the lower temperature of 10degC, the removal reached 98% in the 7th day. Removal rate of P. tenue by the flagellate increased with the increase in temperature and reached the maximal value with 4.0 h{sup -1} at 30degC. The flagellate could contribute to the degradation of MIB, although the degradation was lower than that of P. tenue. It was found that the microflagellate could favorably predate on P. tenue and degrade its metabolite, MIB emitting musty odor in a wide range of temperature. 27 refs., 8 figs., 3 tabs.

  4. Molecular detection and identification of Leishmania infection in naturally infected sand flies in a focus of cutaneous leishmaniasis in northern Morocco

    OpenAIRE

    Es-Sette, Nargys; Ajaoud, Malika; Laamrani-Idrissi, Abderrahman; Mellouki, Fouad; Lemrani, Meryem

    2014-01-01

    Background Cutaneous leishmaniasis is an infectious disease caused by various species of the flagellate protozoan Leishmania. During the past 20 years, cutaneous leishmaniasis has emerged as a major public health threat in Morocco. The main objective of this study was to study the occurrence of Leishmania infection in vectors and to identify sand fly blood meal sources in an endemic locality of cutaneous leishmaniasis within Sefrou province, where the vectors of leishmaniasis were still unkno...

  5. Propulsion of liposomes using bacterial motors

    International Nuclear Information System (INIS)

    Zhang Zhenhai; Li Kejie; Li Zhifei; Yu Wei; Xie Zhihong; Shi Zhiguo

    2013-01-01

    Here we describe the utilization of flagellated bacteria as actuators to propel spherical liposomes by attaching bacteria to the liposome surface. Bacteria were stably attached to liposomes using a cross-linking antibody. The effect of the number of attached bacteria on propulsion speed was experimentally determined. The effects of bacterial propulsion on the bacteria–antibody–liposome complex were stochastic. We demonstrated that liposomal mobility increased when bacteria were attached, and the propulsion speed correlated with the number of bacteria. (paper)

  6. Enrichment of omnivorous cercozoan nanoflagellates from coastal Baltic Sea waters.

    Directory of Open Access Journals (Sweden)

    Kasia Piwosz

    Full Text Available Free-living nano-sized flagellates are important bacterivores in aquatic habitats. However, some slightly larger forms can also be omnivorous, i.e., forage upon both bacterial and eukaryotic resources. This hitherto largely ignored feeding mode may have pronounced implications for the interpretation of experiments about protistan bacterivory. We followed the response of an uncultured group of omnivorous cercozoan nanoflagellates from the Novel Clade 2 (Cerc_BAL02 to experimental food web manipulation in samples from the Gulf of Gdańsk (Southern Baltic Sea. Seawater was either prefiltered through 5 µm filters to exclude larger predators of nanoflagellates (F-treatment, or prefiltered and subsequently 1∶10 diluted with sterile seawater (F+D-treatment to stimulate the growth of both, flagellates and bacteria. Initially, Cerc_BAL02 were rapidly enriched under both conditions. They foraged on both, eukaryotic prey and bacteria, and were highly competitive at low concentrations of food. However, these omnivores were later only successful in the F+D treatment, where they eventually represented almost one fifth of all aplastidic nanoflagellates. By contrast, their numbers stagnated in the F-treatment, possibly due to top-down control by a concomitant bloom of other, unidentified flagellates. In analogy with observations about the enrichment of opportunistically growing bacteria in comparable experimental setups we suggest that the low numbers of omnivorous Cerc_Bal02 flagellates in waters of the Gulf of Gdańsk might also be related to their vulnerability to grazing pressure.

  7. Prey selectivity of bacterivorous protists in different size fractions of reservoir water amended with nutrients

    Czech Academy of Sciences Publication Activity Database

    Jezbera, Jan; Horňák, Karel; Šimek, Karel

    2006-01-01

    Roč. 8, č. 8 (2006), s. 1330-1339 ISSN 1462-2912. [SAME /9./. Helsinky, 21.08.2005-26.08.2005] R&D Projects: GA ČR(CZ) GA206/05/0007 Grant - others:MŠM(CZ) 60076658/01 Institutional research plan: CEZ:AV0Z60170517 Keywords : selectivity * flagellates * grazing * fluorescence * reservoir * nutrients Subject RIV: EE - Microbiology, Virology Impact factor: 4.630, year: 2006

  8. Ciguatera fish poisoning: A first epidemic in Germany highlights an increasing risk for European countries

    OpenAIRE

    Mattei, César; Vetter, Irina; Eisenblätter, Anneka; Krock, Bernd; Ebbecke, Martin; Desel, Herbert; Zimmermann, Katharina

    2014-01-01

    Toxin-producing microalgae are thriving worldwide due to coral reef destruction and global warming with major consequences on ecosystems, international trade and human health. Microalgae belonging to the family of flagellate protists, in particular dinoflagellates, secrete a variety of high-molecular-weight polyether toxins that accumulate through the marine food chain to cause disease in humans by acting as sodium channel activator toxins; ciguatera is the most frequent seafood-borne illness...

  9. Early Cretaceous trypanosomatids associated with fossil sand fly larvae in Burmese amber

    Directory of Open Access Journals (Sweden)

    George Poinar Jr

    2007-08-01

    Full Text Available Early Cretaceous flagellates with characters typical of trypanosomatids were found in the gut of sand fly larvae, as well as in surrounding debris, in Burmese amber. This discovery supports a hypothesis in which free-living trypanosomatids could have been acquired by sand fly larvae in their feeding environment and then carried transtadially into the adult stage. At some point in time, specific genera were introduced into vertebrates, thus establishing a dixenous life cycle.

  10. Miocardite na forma aguda da doença de Chagas

    Directory of Open Access Journals (Sweden)

    Eitel Duarte

    1948-12-01

    Full Text Available The autopsy of a case of CHAGAS'S disease or American tryponosomiasis (a girl, 5 years old, dead in the 22nd day of illness is reported. The anatomic diagnosis was a follows: Acute diffuse chagasic nyocarditis. Chagasic encephalitis. Chagasic lymphadenitis of the right posterior auricular node. Tuberculosis of the bronchial and pulmonary nodes. Chronic passive hyperemia and atelectasia of the lungs. Chronic passive congestion and hemorrhages of the spleen. Serous hepatitis. Parotiditis. Edema of the right eyelids. Bilateral hydrothorax. Hydropericardium. Hydroperitoneum. The morphology of Schizotrypanum cruzi in the myocardium is considered. Besides agglomerates with typical small oval or round intracellular bodies, pre-flagellate and flagellate organisms, others are found in which the great amount of parasites and marked pressure exerted by them against each other render very difficult their identification; sometimes the similitude of such agglamerates to Toxoplasma is striking (Fig. 1 and 1 A. In such a case, the structure of the blepharoplast (Fig. 1 and IA, usually preserved, is profitable and allows the identification of the pre-flagellate and flagellate forms of Schizotrypanum cruzi. Most of the small sensitive nerves in the epicardium shows mononuclear infiltration of the perineurium (perineuritis, Figs. 12-14. Microscopically there is extensive Zenker's degeneration (Figs. 6-8 and parasitism of the heart muscle fibers, marked cellular infiltration of the interstitial connective tissue, which are found in the ordinary musculature of every chamber of the heart (Figs. 10-11 as well as in Tawara's node (Fig. 9, main bundle (Fig. 2 and right (Fig. 4 and left (Fig. 5 septal divisions of the bundle of His, and perineuritis. Those anatomic changes are associated to an abnormal electrocardiogram presenting some similitude to that of an anemic infarct of the anterior wall of the heart and which will be discussed elsewhere (unpublished paper by

  11. Swimming of Microorganisms Viewed from String and Membrane Theories

    OpenAIRE

    Kawamura, Masako; Sugamoto, Akio; Nojiri, Shin'ichi

    1993-01-01

    Swimming of microorganisms is studied from a viewpoint of extended objects (strings and membranes) swimming in the incompressible f luid of low Reynolds number. The flagellated motion is analyzed in two dimensional fluid, by using the method developed in the ciliated motion with the Joukowski transformation. Discussion is given on the conserved charges and the algebra which are associated with the area (volume)- preserving diffeomorphisms giving the swimming motion of microorganisms. It is al...

  12. Photodynamics of BLUF domain proteins: a new class of the biological blue-light photoreceptors

    OpenAIRE

    Zirak Yousefabadi, Peyman

    2008-01-01

    BLUF domains are light sensors of many microorganisms. They are present in the multi-domain proteins e.g. AppA from the phototrophic proteobacterium Rhodobacter sphaeroides, YcgF from Escherichia coli, PAC (photoactive adenylyl cyclase) from the unicellular flagellate Euglena gracilis and single domain proteins e.g. BlrB from Rhodobacter sphaeroides, Slr1694 from cyanobacterium Synechocystis sp.PCC6803, and Tll0078 of the thermophilic unicellular cyanobacterium Thermosynechococcus elongates B...

  13. Boundary Influences on HAB Phytoplankton Ecology in a Stratification-Enhanced Upwelling Shadow

    Science.gov (United States)

    2014-05-13

    localization, tracking and sampling during djal AUV operations (Figs. 12-15). coincident with the cool side of a front (Fig. 12). Abundant gelatinous ...Busse, LB., Mazzillo, F., Silver , M.W.. 2008. The emergence of Cochtodinium along the California Coast (USA). Harmful Algae 7, 337-346. Das, J...p. 89-92. Mazzillo F.F.M.. Ryan J.P.. Silver M.W., 2011 Parasitism as a biological control agent of dino flagellate blooms in the California

  14. Description of Rhynchopus euleeides n. sp. (Diplonemea), a free-living, marine euglenozoan

    Czech Academy of Sciences Publication Activity Database

    Roy, J.; Faktorová, Drahomíra; Benada, Oldřich; Lukeš, Julius; Burger, G.

    2007-01-01

    Roč. 54, č. 2 (2007), s. 137-145 ISSN 1066-5234 R&D Projects: GA AV ČR IAA5022302; GA MŠk 2B06129 Grant - others:Canadian Institutes of Health Research(CA) MOP-79309 Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z60220518 Keywords : Diplonemea * Euglenozoa * flagellates * morphology * taxonomy * ultrastructure Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.525, year: 2007

  15. Association between protozoa in sputum and asthma: a case-control study.

    Science.gov (United States)

    van Woerden, Hugo C; Ratier-Cruz, Adriana; Aleshinloye, Olabode B; Martinez-Giron, Rafael; Gregory, Clive; Matthews, Ian P

    2011-06-01

    Atypical infectious agents have been proposed as potential contributors to asthma. A novel set of morphological and staining criteria permit the identification of flagellated protozoa in sputum. This case-control study was designed to use this novel method and to assess: (1) are protozoa more common in asthmatics than in non-asthmatics; (2) is the presence of protozoa associated with the use of steroid inhalers; and (3) is the presence of protozoa associated with living in damp housing? Induced sputum samples were collected from asthma patients and local non-atopic, non-smoking controls. Questionnaires assessed asthma severity and housing conditions. Sputum was examined for flagellated protozoa using a previously described staining technique. 96 participants were recruited for this study; 54 asthma patients and 42 controls, age range 21-62 years, 70% female participants. Limiting results to those who were clearly positive or negative for flagellated protozoa, 66.7% (20/30) of asthmatics and 30.8% (4/13) of controls had protozoa (p = 0.046). Among the asthma patients, prevalence of protozoa was not significantly different between those who had (10/18), and those who had not (10/12), used steroid inhaler in the preceding two weeks (p = 0.11). Similarly, the prevalence of protozoa was not significantly different between those who did (6/11) and those who did not (18/32), live in damp homes (p = 0.92). This case-control study demonstrates an association between flagellated protozoa in sputum and asthma. It is now necessary to confirm and characterise the protozoa using genetic techniques based on 18S ribosomal RNA. Once tis is established it would be worthwhile to determine if asthma symptoms improve when treated by anti-protozoal agents. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Joint Program on Molecular Biology of Marine Organisms

    Science.gov (United States)

    1992-08-20

    and lateral flagella formation in a marine vibrio (Belas and Colwell, 1982). Upon contact with a surface, the polar flagella of Vibrio ... parahemolyticus ceased to function. Shortl’ thereafter, lateral flagella formed around the cells, apparently mediating the "irreversible" attachment process. Pilus...Colwell. 1982. Adsorption kinetics of 18 Slaterally and polarly flagellated Vibrio . J. Bacteriol. 151:1568-1580. S-- Brown, C.M., D.C. Ellwood, and

  17. Trichomoniasis in Bothrops jararaca (serpentes, viperidae

    Directory of Open Access Journals (Sweden)

    F. C. Vilela

    2003-01-01

    Full Text Available We describe a case of trichomoniasis in a Bothrops jararaca (Serpentes, Viperidae donated to the Center for the Study of Venoms and Venomous Animals - CEVAP/UNESP. The animal had diarrhea with great quantity of flagellated protozoa in the feces. Microscopic examination of fecal smears stained with Giemsa revealed the presence of trichomonads, morphologically similar to Trichomonas acosta. Trichomonads were not detected in fecal exams after treatment with a single dose of 40 mg/kg metronidazole (Flagyl®.

  18. Trypanosomes - versatile microswimmers

    Science.gov (United States)

    Krüger, Timothy; Engstler, Markus

    2016-11-01

    Evolution has generated a plethora of flagellate microswimmers. They populate all natural waters, from the deep sea to the ponds in our neighbourhood. But flagellates also thrive in the bodies of higher organisms, where they mostly remain undetected, but can also become pathogenic. Trypanosomes comprise a large group of mostly parasitic flagellates that cause many diseases, such as human sleeping sickness or the cattle plague nagana. We consider African trypanosomes as extremely versatile microswimmers, as they have to adapt to very diverse microenvironments. They swim efficiently in the blood of their mammalian hosts, but also in various tissue spaces and even in the human brain. Furthermore, in the transmitting tsetse fly, trypanosomes undergo characteristic morphological changes that are accompanied by amazing transitions between solitary and collective types of motion. In this review, we provide a basic introduction to trypanosome biology and then focus on the complex type of rotational movement that trypanosomes display. We relate their swimming performance to morphological parameters and the respective microenvironment, developing a contemporary view on the physics of trypanosome motility. The genetically programmed successions of life style-dependent motion patterns provide challenges and opportunities for interdisciplinary studies of microswimmers.

  19. Epidemiological factors related to the transmission risk of Trypanosoma cruzi in a Quilombola community, State of Mato Grosso do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Marlon Cezar Cominetti

    2011-10-01

    Full Text Available INTRODUCTION: This work was an epidemiological investigation of the risk of Trypanosoma cruzi transmission in the rural Quilombola community of Furnas do Dionízio, State of Mato Grosso do Sul, Brazil. METHODS: Of the 71 animals examined, seven were captured (two opossums, Didelphis albiventris; four rats, Rattus rattus; and one nine-banded armadillo, Dasypus novemcinctus and 64 were domestic (one canine, Canis familiaris; five pigs, Sus scrofa; two bovines, Bos taurus; five caprines, Capra sp.; and 51 ovines, Ovis aries. Parasitological tests were performed to detect parasites in the blood and to identify the morphology of flagellates. These methods included fresh examinations, buffy coat tests and blood cultures. Molecular analysis of DNA for identification of trypanosomatids was performed by polymerase chain reaction (PCR with primers S35 and S36. RESULTS: The parasitological tests showed flagellates in an opossum and two cattle. The molecular tests showed DNA from T. cruzi in an opossum and a pig. Triatoma sordida was the only triatomine species found in the community, and it colonized households (four specimens and the surrounding areas (124 specimens. Twenty-three specimens tested positive for flagellates, which were subsequently identified as T. cruzi by PCR. CONCLUSIONS: Data analysis demonstrated that T. cruzi has a peridomestic life cycle that involves both domestic and wild mammals.

  20. Responses of KT2440 Pseudomonas putida to mild water stress

    DEFF Research Database (Denmark)

    Gülez, Gamze

    betydningen af flagellær motilitet og produktion af EPS under matric stess undersøgt ved brug af den såkaldte Porous Surface Model (PSM), som genererer væske-filmens effekter ved kontrol af !m. Det blev vist, at flagellær motilitet var begrænset under matric stress; Pseudomonas putida KT2440 kolonier udviste...... væsentlig højere vækstrater tæt ved mætningsbetingelser (-0.5 kPa !m) end kolonier dyrket under matric stress (ved -3.6 kPa !m). Desuden viste 1:1 kompettitive eksperimenter med begge phenotyper ved mættede betingelser, at den naturligt forekomne KT2440 udkonkurrerer dens ikke-flagellare mutant med hensyn...... til overflade-kolonivækst, hvorimod begge phenotyper sameksisterer under matric stress (-3.6 kPa). Denne afhandling har endvidere vist at bakterierne kunne drage fordel af pludseligt forekomne mættede betingelser (5 minutter, to gange dagligt) idet flagellær motilitet blev observeret. Dette resultat...

  1. The Flagellar Regulon of Legionella—A Review

    Science.gov (United States)

    Appelt, Sandra; Heuner, Klaus

    2017-01-01

    The Legionella genus comprises more than 60 species. In particular, Legionella pneumophila is known to cause severe illnesses in humans. Legionellaceae are ubiquitous inhabitants of aquatic environments. Some Legionellaceae are motile and their motility is important to move around in habitats. Motility can be considered as a potential virulence factor as already shown for various human pathogens. The genes of the flagellar system, regulator and structural genes, are structured in hierarchical levels described as the flagellar regulon. Their expression is modulated by various environmental factors. For L. pneumophila it was shown that the expression of genes of the flagellar regulon is modulated by the actual growth phase and temperature. Especially, flagellated Legionella are known to express genes during the transmissive phase of growth that are involved in the expression of virulence traits. It has been demonstrated that the alternative sigma-28 factor is part of the link between virulence expression and motility. In the following review, the structure of the flagellar regulon of L. pneumophila is discussed and compared to other flagellar systems of different Legionella species. Recently, it has been described that Legionella micdadei and Legionella fallonii contain a second putative partial flagellar system. Hence, the report will focus on flagellated and non-flagellated Legionella strains, phylogenetic relationships, the role and function of the alternative sigma factor (FliA) and its anti-sigma-28 factor (FlgM). PMID:29104863

  2. Protozooplankton in the Deep Oligotrophic Traunsee (Austria) Influenced by Discharges of Soda and Salt Industries

    International Nuclear Information System (INIS)

    Sonntag, Bettina; Posch, Thomas; Klammer, Susanne; Griebler, Christian; Psenner, Roland

    2002-01-01

    Traunsee is a deep oligotrophic lake in Austria characterised by an artificial enrichment of chloride in the hypolimnion (up to 170 mg L -1 ) caused by waste disposal of soda and salt industries. Protists were collected monthly over one year, observed alive and after Quantitative Protargol Staining (ciliates) or via epifluorescence microscopy (heterotrophic flagellates). Three sites within the lake (0-40 m depths) were compared to deeper water layers from 60-160 m depths where chloride concentrations and conductivity were increased. In addition, we observed the protozooplankton of two neighbouring lakes, i.e. reference systems, during one sampling occasion. In Traunsee the abundance of ciliates was low (200-36 600 cells L -1 ) in contrast to high species diversity (at least 60 different species; H S = 2.6) throughout the year. The main pelagic species in terms of abundance were small oligotrichs and prostomatids like Rimostrombidium brachykinetum/hyalinum, Balanion planctonicum and Urotricha spp. throughout the investigation period. Among free-living heterotrophic flagellates, which occurred at densities of 40-2800 cells mL -1 , small morphotypes dominated in the pelagial. No differences at the community level between the three lakes could be observed and pelagic ciliates and flagellates seemed not to be affected by increased chloride concentrations or by enhanced conductivity

  3. Protozooplankton in the Deep Oligotrophic Traunsee (Austria) Influenced by Discharges of Soda and Salt Industries

    Energy Technology Data Exchange (ETDEWEB)

    Sonntag, Bettina, E-mail: bettina.sonntag@uibk.ac.at; Posch, Thomas [University of Innsbruck, Institute of Zoology and Limnology (Austria); Klammer, Susanne [University of Innsbruck, Institute of Microbiology (Austria); Griebler, Christian [University of Tuebingen, Centre for Applied Earth Science (Germany); Psenner, Roland [University of Innsbruck, Institute of Zoology and Limnology (Austria)

    2002-07-15

    Traunsee is a deep oligotrophic lake in Austria characterised by an artificial enrichment of chloride in the hypolimnion (up to 170 mg L{sup -1}) caused by waste disposal of soda and salt industries. Protists were collected monthly over one year, observed alive and after Quantitative Protargol Staining (ciliates) or via epifluorescence microscopy (heterotrophic flagellates). Three sites within the lake (0-40 m depths) were compared to deeper water layers from 60-160 m depths where chloride concentrations and conductivity were increased. In addition, we observed the protozooplankton of two neighbouring lakes, i.e. reference systems, during one sampling occasion. In Traunsee the abundance of ciliates was low (200-36 600 cells L{sup -1}) in contrast to high species diversity (at least 60 different species; H{sub S} = 2.6) throughout the year. The main pelagic species in terms of abundance were small oligotrichs and prostomatids like Rimostrombidium brachykinetum/hyalinum, Balanion planctonicum and Urotricha spp. throughout the investigation period. Among free-living heterotrophic flagellates, which occurred at densities of 40-2800 cells mL{sup -1}, small morphotypes dominated in the pelagial. No differences at the community level between the three lakes could be observed and pelagic ciliates and flagellates seemed not to be affected by increased chloride concentrations or by enhanced conductivity.

  4. Use of genetically marked minicells as a probe in measurement of predation on bacteria in aquatic environments

    International Nuclear Information System (INIS)

    Wikner, J.; Andersson, A.; Normark, S.; Hagstroem, A.

    1986-01-01

    Minicells produced by Escherichia coli M2141 were used as probes to measure predation on pelagic bacteria in situ. The minicells, labeled with [ 35 S]methionine in one specific protein, were shown to disappear in the presence of a microflagellate (Ochromonas sp.), as seen by a decrease in the amount of labeled marker protein with time. Incubation in filtered (pore size, 0.2 μm) and autoclaved seawater did not affect the amount of labeled marker protein in the minicell. The generation time of flagellates feeding on minicells was determined to be similar to that found for flagellates grown on seawater bacteria or living E. coli NC3. Data indicate that minicells are seen as true food particles by the flagellates. The minicell probe was used in recapture experiments, in which predation in situ on pelagic bacteria was demonstrated. The rate of bacterial production showed a clear covariation with the rate of predation, both in different sea areas and in depth profiles. The obtained results (11 field experiments) showed that the rate of predation, on average, accounts for the consumption of 62% of the bacteria produced

  5. Prevalence of different Malassezia species in pityriasis versicolor in central India

    Directory of Open Access Journals (Sweden)

    Chaudhary Rahul

    2010-01-01

    Full Text Available Background: In the last 10 years, different studies have shown interesting geographical variations in the prevalence of different Malassezia species in pityriasis versicolor. Aim: Identification of Malassezia species isolated from patients with pityriasis versicolor. Methods: In 100 patients with pityriasis versicolor, Malassezia species were identified by culture in Sabouraud′s dextrose agar containing cycloheximide with olive oil overlay and modified Dixon agar and by doing biochemical tests (catalase reaction, assimilation of glycine, and Tween utilisation tests. Results: In 10 patients, 10% KOH smear was negative, while in 90 patients the smear showed characteristic "spaghetti and meatball" appearance. Of these 90 cases, growth was obtained on modified Dixon′s agar in 87 cases. Fifty of the isolates (57.5% were M. globosa, 15 (17.2% were M. sympodialis, seven (8.0% were suspected M. sympodialis, 6 (6.9% each of the isolates were M. furfur and M. obtusa, and three (3.4% isolates were M. restricta. Conclusion: M. globosa was the most common species, followed by M. sympodialis, M. furfur, M. obtusa, and M. restricta.

  6. Prevalence of different Malassezia species in pityriasis versicolor in central India.

    Science.gov (United States)

    Chaudhary, Rahul; Singh, Sanjay; Banerjee, Tuhina; Tilak, Ragini

    2010-01-01

    In the last 10 years, different studies have shown interesting geographical variations in the prevalence of different Malassezia species in pityriasis versicolor. Identification of Malassezia species isolated from patients with pityriasis versicolor. In 100 patients with pityriasis versicolor, Malassezia species were identified by culture in Sabouraud's dextrose agar containing cycloheximide with olive oil overlay and modified Dixon agar and by doing biochemical tests (catalase reaction, assimilation of glycine, and Tween utilisation tests). In 10 patients, 10% KOH smear was negative, while in 90 patients the smear showed characteristic "spaghetti and meatball" appearance. Of these 90 cases, growth was obtained on modified Dixon's agar in 87 cases. Fifty of the isolates (57.5%) were M. globosa, 15 (17.2%) were M. sympodialis, seven (8.0%) were suspected M. sympodialis, 6 (6.9%) each of the isolates were M. furfur and M. obtusa, and three (3.4%) isolates were M. restricta. M. globosa was the most common species, followed by M. sympodialis, M. furfur, M. obtusa, and M. restricta.

  7. Pitiríase versicolor: isolamento e identificação das principais espécies de Malassezia Pityriasis versicolor: isolation and identification of the main species

    Directory of Open Access Journals (Sweden)

    Valéria Maria de Souza Framil

    2010-02-01

    Full Text Available As espécies do gênero Malassezia isoladas foram: Malassezia sympodialis (16,66%, Malassezia furfur (12,50%, Malassezia globosa (11,45% e Malassezia slooffiae (2,10%. A Malassezia sympodialis foi a espécie que predominou em nosso estudo. As espécies de Malassezia identificadas não mostraram correlação com as variantes clínicas e com a distribuição das lesões de pitiríase versicolor quanto às regiões do corpo.Species of the genus Malassezia isolated were: Malassezia sympodialis (16.66%, Malassezia furfur (12.50%, Malassezia globosa (11.45%, and Malassezia slooffiae (2.10%. Malassezia sympodialis predominated in the study. The species of Malassezia identified did not show correlation with clinical variants and with the distribution of pityriasis versicolor lesions in relation to areas of the body.

  8. Two cases of sporotrichosis of the right upper extremity in right-handed patients with diabetes mellitus.

    Science.gov (United States)

    Zhang, Yu; Hagen, Ferry; Wan, Zhe; Liu, Yufu; Liu, Yahong; Wang, Qingwen; de Hoog, Gert Sybren; Li, Ruoyu; Zhang, Junling

    2016-01-01

    Sporothrix species have proved to show high degrees of endemicity. Sporothrix globosa is the only pathogenic Sporothrix species that has till date been reported from China, where it is endemic in the northeastern provinces. We report two cases of lymphocutaneous sporotrichosis with diabetes mellitus as underlying disease in patients from the non-endemic area of China. A 59-year-old farmer and a 60-year-old gardener were admitted in February and June 2014, respectively. Both patients were right-handed men and presented with progressive plaques and nodules, which they had for several years, involving the right upper extremity. Skin biopsy from the granuloma was taken and cultured on Sabouraud medium, and molecular identification based on the calmodulin region was performed. Antifungal susceptibility testing was also performed with the microdilution method. Biopsy of the lesions showed the presence of infectious granuloma. The fungal cultures were identified as Sporothrix globosa by conventional methods, and confirmed by molecular identification. A subsequent course of oral antifungal therapy with low dosage of itraconazole was well tolerated and resolved the infection. Identification of fungal species and antifungal susceptibility testing are mandatory for epidemiological and therapeutic reasons. Early diagnosis of sporotrichosis is essential to prevent those sequelae when the disease progresses and provides highly effective methods for treating this emerging disease. Avoiding the exposure to plant material potentially contaminated with fungal spores should be recommended, especially in immunocompromised patients. Copyright © 2015 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  9. Human sporotrichosis beyond the epidemic front reveals classical transmission types in Espírito Santo, Brazil.

    Science.gov (United States)

    de Araujo, Mariceli L; Rodrigues, Anderson M; Fernandes, Geisa F; de Camargo, Zoilo P; de Hoog, G Sybren

    2015-08-01

    Sporotrichosis has emerged as the main subcutaneous mycosis of humans and animals around the world. With particular differences in frequency, the major species includes Sporothrix brasiliensis, S. schenckii, S. globosa and S. luriei. In Brazil, the main aspect of this epidemic is based on the zoonotic transmission through the scratches and bites of diseased cats contaminated with S. brasiliensis. Areas free of feline sporotrichosis are poorly characterised in Brazil. We investigated by molecular tools the epidemiology of human sporotrichosis in the Espírito Santo (ES) state, an area adjacent to Rio de Janeiro where is the epicentre of the long-lasting outbreak of cat-transmitted sporotrichosis. The human cases in the ES state reveal the prevalence of classical transmission types where subjects are mainly infected by accidental traumatic inoculation during manipulation of contaminated plant material. In agreement with an environmental source, Sporothrix schenckii was the major aetiological agent in the classical transmission. Unlike Rio de Janeiro, this study shows that cat-transmitted epidemic in Espírito Santo is still scanty, although the geographic proximity and similar climatic features. Sporothrix brasiliensis was the agent in the feline-transmitted cases. Sporothrix globosa was isolated from a patient with fixed cutaneous lesions that did not report any contact with diseased animals. In conclusion, beyond the borders of Rio de Janeiro epidemic, agents of sporotrichosis in Espírito Santo show a scattered occurrence with high species diversity. © 2015 Blackwell Verlag GmbH.

  10. Phenotypic Characteristics Associated with Virulence of Clinical Isolates from the Sporothrix Complex

    Science.gov (United States)

    Almeida-Paes, Rodrigo; de Oliveira, Luã Cardoso; Oliveira, Manoel Marques Evangelista; Gutierrez-Galhardo, Maria Clara; Nosanchuk, Joshua Daniel; Zancopé-Oliveira, Rosely Maria

    2015-01-01

    The Sporothrix complex members cause sporotrichosis, a subcutaneous mycosis with a wide spectrum of clinical manifestations. Several specific phenotypic characteristics are associated with virulence in many fungi, but studies in this field involving the Sporothrix complex species are scarce. Melanization, thermotolerance, and production of proteases, catalase, and urease were investigated in 61 S. brasiliensis, one S. globosa, and 10 S. schenckii strains. The S. brasiliensis strains showed a higher expression of melanin and urease compared with S. schenckii. These two species, however, presented similar thermotolerances. Our S. globosa strain had low expression of all studied virulence factors. The relationship between these phenotypes and clinical aspects of sporotrichosis was also evaluated. Strains isolated from patients with spontaneous regression of infection were heavily melanized and produced high urease levels. Melanin was also related to dissemination of internal organs and protease production was associated with HIV-coinfection. A murine sporotrichosis model showed that a S. brasiliensis strain with high expression of virulence factors was able to disseminate and yield a high fungal burden in comparison with a control S. schenckii strain. Our results show that virulence-related phenotypes are variably expressed within the Sporothrix complex species and might be involved in clinical aspects of sporotrichosis. PMID:25961005

  11. In vitro tests and ethnopharmacological investigations: wound healing as an example.

    Science.gov (United States)

    Houghton, P J; Hylands, P J; Mensah, A Y; Hensel, A; Deters, A M

    2005-08-22

    In vitro tests are now widely employed in ethnopharmacological research because of ethical reasons and their usefulness in bioactive-guided fractionation and determination of active compounds. For many disease conditions, a variety of in vitro tests can now be employed as the biochemical mechanisms underlying disease and healing processes are understood. Approaches to the in vitro investigations of wound healing processes are exemplified by studies on extracts of Buddleja species and three Ghanaian species Spathodea campanulata, Commelina diffusa and Secamone afzelii. Most studies have been carried out on Buddleja officinalis or Buddleja globosa. The extracts have been shown to have anti-inflammatory and antioxidant properties due to flavonoids, triterpenoids, diterpenoids and caffeic acid derivatives. There appears to a slight effect on proliferation of fibroblasts at lower concentrations, but this was not significant, and higher concentrations appeared to be cytotoxic. Novel findings are the ability of Buddleja globosa leaf extracts to induce differentiation in keratinocytes and to alter the profile of proteins produced by cultured fibroblasts. Extracts also had some effect on lattice contraction. The three Ghanaian species examined show a mixture of antimicrobial and antioxidant activities. The evolution over recent years of tests for wound healing, from in vivo tests to cell-based systems and chemical reactions and on to investigations into effects on secondary messengers and protein expression, is described.

  12. DPPH and oxygen free radicals as pro-oxidant of biomolecules.

    Science.gov (United States)

    Letelier, María Eugenia; Molina-Berríos, Alfredo; Cortés-Troncoso, Juan; Jara-Sandoval, José; Holst, Marianne; Palma, Karina; Montoya, Margarita; Miranda, Dante; González-Lira, Víctor

    2008-03-01

    Numerous investigations exist about the alterations that oxygen free radicals can provoke on biomolecules; these modifications can be prevented and/or reversed by different antioxidants agents. On the other hand, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), a stable nitrogen synthetic radical, is used to evaluate the antioxidant capacity of medicinal herbal products; however, the structural changes that this radical provoke on the herbal active principles are not clear yet. In this work, we compared the redox reactivity of oxygen free radicals and DPPH radical on phospholipids and protein thiol groups present in rat liver microsomes. Cu2+/ascorbate was used as generator system of oxygen free radical and as antioxidant, an extract of Buddleja globosa's leaves. Cu2+/ascorbate provoked microsomal lipid peroxidation, microsomal thiols oxidation and oxygen consumption; all of these phenomena were inhibited by B. globosa extract. On the other hand, DPPH was bleached in different extension by the herbal extract and phosphatidyl choline; beside, DPPH decreased microsomal thiols content, but this phenomenon were not prevented by the herbal extract. Furthermore, DPPH did not induce oxygen consumption and neither modified the oxygen consumption induced by Cu2+/ascorbate. Distinct redox mechanisms may explain the differences between the reactivity of DPPH and oxygen free radicals on biomolecules, which is discussed.

  13. Boraginaceae s.l. A. Juss. em uma área de Caatinga da ESEC Raso da Catarina, BA, Brasil Boraginaceae s.l. A. Juss. in the Caatinga of the Raso da Catarina Ecological Station, Bahia State, Brazil

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    José Iranildo Miranda de Melo

    2007-06-01

    Full Text Available Este trabalho trata do levantamento florístico-taxonômico da família Boraginaceae em um trecho de Caatinga da Estação Ecológica Raso da Catarina, Bahia, Brasil. Foram encontrados sete espécies e três gêneros de Boraginaceae: Cordia (C. globosa (Jacq. Kunth, C. leucocephala Moric. e C. rufescens A.DC., Heliotropium (H. angiospermum Murray e Heliotropium elongatum (Lehm. I.M. Johnst. e Tournefortia (T. rubicunda Salzm. ex A.DC. e T. salzmannii DC.. São apresentadas chaves para identificação de gêneros e espécies, além de descrições, ilustrações, comentários, dados de distribuição e hábitat.A floristic-taxonomic survey of the family Boraginaceae was carried out in a fragment of Caatinga vegetation of the Raso da Catarina Ecological Station, Bahia, Brazil. Seven species and three genera of Boraginaceae were found: Cordia (C. globosa (Jacq. Kunth; C. leucocephala Moric.; C. rufescens A.DC., Heliotropium (H. angiospermum Murray; H. elongatum (Lehm. I.M. Johnst. and Tournefortia (T. rubicunda Salzm. ex A.DC.; T. salzmannii DC.. Keys to identify genera and species are presented together with descriptions, illustrations, and comments on relationships among these taxa, distribution and habitat.

  14. Sporothrix schenckii COMPLEX:SUSCEPTIBILITIES TO COMBINED ANTIFUNGAL AGENTS AND CHARACTERIZATION OF ENZYMATIC PROFILES.

    Science.gov (United States)

    Oliveira, Daniele Carvalho; de Loreto, Érico Silva; Mario, Débora Alves Nunes; Lopes, Paulo G Markus; Neves, Louise Vignolles; da Rocha, Marta Pires; Santurio, Janio Morais; Alves, Sydney Hartz

    2015-01-01

    Sporothrix schenckii was reclassified as a complex encompassing six cryptic species, which calls for the reassessment of clinical and epidemiological data of these new species. We evaluated the susceptibility of Sporothrix albicans(n = 1) , S. brasiliensis(n = 6) , S. globosa(n = 1), S. mexicana(n = 1) and S. schenckii(n = 36) to terbinafine (TRB) alone and in combination with itraconazole (ITZ), ketoconazole (KTZ), and voriconazole (VRZ) by a checkerboard microdilution method and determined the enzymatic profile of these species with the API-ZYM kit. Most interactions were additive (27.5%, 32.5% and 5%) or indifferent (70%, 50% and 52.5%) for TRB+KTZ, TRB+ITZ and TRB+VRZ, respectively. Antagonisms were observed in 42.5% of isolates for the TRB+VRZ combination. Based on enzymatic profiling, the Sporothrix schenckii strains were categorized into 14 biotypes. Leucine arylamidase (LA) activity was observed only for S. albicans and S. mexicana. The species S. globosa and S. Mexicana were the only species without β-glucosidase (GS) activity. Our results may contribute to a better understanding of virulence and resistance among species of the genus Sporothrix in further studies.

  15. Viral attack exacerbates the susceptibility of a bloom-forming alga to ocean acidification.

    Science.gov (United States)

    Chen, Shanwen; Gao, Kunshan; Beardall, John

    2015-02-01

    Both ocean acidification and viral infection bring about changes in marine phytoplankton physiological activities and community composition. However, little information is available on how the relationship between phytoplankton and viruses may be affected by ocean acidification and what impacts this might have on photosynthesis-driven marine biological CO2 pump. Here, we show that when the harmful bloom alga Phaeocystis globosa is infected with viruses under future ocean conditions, its photosynthetic performance further decreased and cells became more susceptible to stressful light levels, showing enhanced photoinhibition and reduced carbon fixation, up-regulation of mitochondrial respiration and decreased virus burst size. Our results indicate that ocean acidification exacerbates the impacts of viral attack on P. globosa, which implies that, while ocean acidification directly influences marine primary producers, it may also affect them indirectly by altering their relationship with viruses. Therefore, viruses as a biotic stressor need to be invoked when considering the overall impacts of climate change on marine productivity and carbon sequestration. © 2014 John Wiley & Sons Ltd.

  16. Jenis dan Kandungan Tanin Pakan Satwa Anoa (Bubalus sp.

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    M. Basri

    2011-04-01

    Full Text Available Study of kinds and tannin content of diets consumed by anoa is limited. This information is very important and necessary for anoa domestication. The aims of this research were to obtain information on kinds and tannin content of anoa diets. The research was conducted in forest of Pangi Binangga nature reserve and Lore Lindu National Park, province of Central Sulawesi in March to November 2009. Digestive content analyses method was used to study the kinds of diets consumed by anoa. Chromatography was used for tannin analysis. Results of the digestive content analysis found ten kinds of anoa diets, i.e. Ficus miquelly, Caryota mitis, Ficus ampelas, Syzigium sp., Cordia mixab, Paspalum conjugatum, Smilax leocophylla, Saccarum spontaneum, Isachne globosa and Imperata cylindrica. The proportion of the diets were 60%, 45%, 35%, 17%, 12%, 10%, 8%, 8%, 5%, and 4%, respectively. Three of six diets namely Ficus miquelly, Saccarum spontaneum and Isachne globosa contained low tannin. The tannin content of three diets was 0.34%, 0.61%, and 0.99%, respectively. It is concluded that anoa in forest prefer diets that contain low tannin, such as Ficus fruits, shoots of shrubs.

  17. Winter-summer succession of unicellular eukaryotes in a meso-eutrophic coastal system.

    Science.gov (United States)

    Christaki, Urania; Kormas, Konstantinos A; Genitsaris, Savvas; Georges, Clément; Sime-Ngando, Télesphore; Viscogliosi, Eric; Monchy, Sébastien

    2014-01-01

    The objective of this study was to explore the succession of planktonic unicellular eukaryotes by means of 18S rRNA gene tag pyrosequencing in the eastern English Channel (EEC) during the winter to summer transition. The 59 most representative (>0.1%, representing altogether 95% of total reads), unique operational taxonomic units (OTUs) from all samples belonged to 18 known high-level taxonomic groups and 1 unaffiliated clade. The five most abundant OTUs (69.2% of total reads) belonged to Dinophyceae, Cercozoa, Haptophyceae, marine alveolate group I, and Fungi. Cluster and network analysis between samples distinguished the winter, the pre-bloom, the Phaeocystis globosa bloom and the post-bloom early summer conditions. The OTUs-based network revealed that P. globosa showed a relatively low number of connections-most of them negative-with all other OTUs. Fungi were linked to all major taxonomic groups, except Dinophyceae. Cercozoa mostly co-occurred with the Fungi, the Bacillariophyceae and several of the miscellaneous OTUs. This study provided a more detailed exploration into the planktonic succession pattern of the EEC due to its increased depth of taxonomic sampling over previous efforts based on classical monitoring observations. Data analysis implied that the food web concept in a coastal system based on predator-prey (e.g. grazer-phytoplankton) relationships is just a part of the ecological picture; and those organisms exploiting a variety of strategies, such as saprotrophy and parasitism, are persistent and abundant members of the community.

  18. Especies de Malassezia aisladas de pacientes con lesiones dermatológicas

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    Sandra Rincón

    2005-06-01

    Full Text Available Introducción. Las levaduras del género Malassezia forman parte de la flora normal de la piel y se asocian con varios tipos de lesiones dermatológicas. Desde 1996, la descripción de nuevas especies dentro de este género planteó numerosos interrogantes sobre su epidemiología y patogenicidad. Objetivo. El fin de este trabajo fue encontrar la frecuencia de las diferentes especies de Malassezia en individuos con pitiriasis versicolor, dermatitis atópica, dermatitis seborreica, dermatitis seborreica en pacientes positivos para VIH, y en individuos sin lesiones a partir de tres zonas corporales (cabeza, tórax, extremidades inferiores y superiores. Materiales y métodos. Se identificaron 154 aislamientos de especies de Malassezia de 112 individuos: 39 con dermatitis seborreica de los cuales 20 eran positivos para VIH, 18 con pitiriasis versicolor, 18 con dermatitis atópica y 37 individuos sin lesión dermatológica (controles. Las escamas de piel de los pacientes se observaron microscópicamente y las muestras de pacientes y controles se cultivaron en agar Dixon modificado. Posteriormente, se observaron las colonias y se identificaron según sus características macroscópicas, microscópicas y fisiológicas. Resultados. Las especies más frecuentemente aisladas en el total de los grupos estudiados fueron: Malassezia globosa (37,5%, M. sympodialis (31,3% y M. furfur (31,3%. M. globosa predominó en los aislamientos de pacientes con pitiriasis versicolor (67% y en pacientes positivos para VIH con dermatitis seborreica (85%. En pacientes con dermatitis atópica y dermatitis seborreica sin diagnóstico de VIH, se aislaron M. furfur y M. restricta en el 72% y el 26% de los casos, respectivamente. Conclusiones. Las diferentes especies de Malassezia pueden aislarse de pacientes con lesiones dermatológicas o sin ellas. Además, la frecuencia de especies en la población muestreada difiere de lo reportado en otras zonas geográficas. Se destaca la

  19. Comparative Genomics of Chrysochromulina Ericina Virus and Other Microalga-Infecting Large DNA Viruses Highlights Their Intricate Evolutionary Relationship with the Established Mimiviridae Family.

    Science.gov (United States)

    Gallot-Lavallée, Lucie; Blanc, Guillaume; Claverie, Jean-Michel

    2017-07-15

    Chrysochromulina ericina virus CeV-01B (CeV) was isolated from Norwegian coastal waters in 1998. Its icosahedral particle is 160 nm in diameter and encloses a 474-kb double-stranded DNA (dsDNA) genome. This virus, although infecting a microalga (the haptophyceae Haptolina ericina , formerly Chrysochromulina ericina ), is phylogenetically related to members of the Mimiviridae family, initially established with the acanthamoeba-infecting mimivirus and megavirus as prototypes. This family was later split into two genera ( Mimivirus and Cafeteriavirus ) following the characterization of a virus infecting the heterotrophic stramenopile Cafeteria roenbergensis (CroV). CeV, as well as two of its close relatives, which infect the unicellular photosynthetic eukaryotes Phaeocystis globosa (Phaeocystis globosa virus [PgV]) and Aureococcus anophagefferens (Aureococcus anophagefferens virus [AaV]), are currently unclassified by the International Committee on Viral Taxonomy (ICTV). The detailed comparative analysis of the CeV genome presented here confirms the phylogenetic affinity of this emerging group of microalga-infecting viruses with the Mimiviridae but argues in favor of their classification inside a distinct clade within the family. Although CeV, PgV, and AaV share more common features among them than with the larger Mimiviridae , they also exhibit a large complement of unique genes, attesting to their complex evolutionary history. We identified several gene fusion events and cases of convergent evolution involving independent lateral gene acquisitions. Finally, CeV possesses an unusual number of inteins, some of which are closely related despite being inserted in nonhomologous genes. This appears to contradict the paradigm of allele-specific inteins and suggests that the Mimiviridae are especially efficient in spreading inteins while enlarging their repertoire of homing genes. IMPORTANCE Although it infects the microalga Chrysochromulina ericina , CeV is more closely

  20. Bioaccumulation of Cs-137 and Co-57 by marine phytoplankton

    International Nuclear Information System (INIS)

    Heldal, H.E.; Stupakoff, I.; Fisher, N.S.

    1999-01-01

    Under controlled laboratory conditions we have examined the bioaccumulation of Cs-137 and Co-57 in three prymnesiophytes, the coccolithophorid Emiliania huxleyi and the non-calcareous species Isochrysis galbana and Phaeocystis globosa, and two diatoms Skeletonema costatum and Thalassiosira pseudonana. We measured uptake in growing and non-growing cells, and determined concentration factors on both volume and dry weight basis. For Co-57 uptake in non-growing cells, volume concentration factors (VCF) at equilibrium ranged from 0.2 * 10 3 for Emiliana huxleyi to 4 * 10 3 for the diatom Thalassiosira pseudonana. For Cs-137 uptake in non-growing cells the VCFs were close to zero. The results suggest that, in contrast to Co, the cycling and bioaccumulation in animals of Cs in marine systems is unlikely to be affected by primary producers. (au)

  1. Bioaccumulation of 137Cs and 57Co by five marine phytoplankton species

    International Nuclear Information System (INIS)

    Heldal, H.E.; Stupakoff, I.; Fisher, N.S.

    2001-01-01

    Under controlled laboratory conditions, we have examined the bioaccumulation of 137 Cs and 57 Co in three prymnesiophytes, the coccolithophorid Emiliania huxleyi and the non-calcareous species Isochrysis galbana and Phaeocystis globosa, and two diatoms Skeletonema costatum and Thalassiosira pseudonana. We measured the uptake in growing and non-growing cells and determined concentration factors on both volume and dry weight bases. For uptake of 57 Co in non-growing cells, volume concentration factors (VCF) at equilibrium ranged from 0.2x10 3 for E. huxleyi to 4x10 3 for T. pseudonana. For uptake of 137 Cs in non-growing cells, the VCFs were low for all species and the uptake pattern seemed unsystematic. The results suggest that, in contrast to Co, the cycling and bioaccumulation of Cs in marine animals are unlikely to be affected by Cs accumulation in primary producers

  2. Management of Cosmetic Embarrassment Caused by Malassezia spp. with Fruticose Lichen Cladia Using Phylogenetic Approach

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    Anand Pandey

    2013-01-01

    Full Text Available During anti-Malassezia screening of plants by CLSI broth microdilution method, Cladia aggregata (Swartz Nyl. (family Cladoniaceae, a fruticose lichen from Sikkim (northeast Himalayan region, has been found effective at minimum inhibitory concentrations (mg/mL of 2.72, 0.63, and 1.28 against yeast-like fungi namely, M. furfur, M. globosa and M. sympodialis, respectively. These test pathogens are responsible for pityriasis versicolor (PV and seborrheic dermatitis (SD in humans. We tried to establish the reason for variable MICs against various Malassezia spp. using bioinformatical tools, thereby reducing the cost of the experimentation. This is the first report on anti-Malassezia activity of C. aggregata and thus can serve as a potential source for the development of cosmaceuticals.

  3. Molecular identification of Sporothrix species involved in the first familial outbreak of sporotrichosis in the state of Espírito Santo, southeastern Brazil.

    Science.gov (United States)

    Oliveira, Manoel Marques Evangelista; Maifrede, Simone Bravim; Ribeiro, Mariceli Araújo; Zancope-Oliveira, Rosely Maria

    2013-11-01

    Sporotrichosis is a widespread subcutaneous mycosis caused by the dimorphic fungi now known as the Sporothrix schenckii complex. This complex is comprised of at least six species, including Sporothrix albicans, Sporothrix brasiliensis, Sporothrix globosa, Sporothrix luriei, Sporothrix mexicana and S. schenckii. Cases of sporotrichosis have significantly increased in Brazil over the past decade, especially in the state of Rio de Janeiro (RJ), where an epidemic among cat owners has been observed. The zoonotic transmission from cats to humans suggests a common source of infection and indicates that animals can act as vectors. We performed a molecular characterisation of samples collected during the first outbreak of familial sporotrichosis caused by S. brasiliensis in the state of Espírito Santo, Brazil. These results represent the first description of such an outbreak outside the endemic area of zoonotic sporotrichosis in RJ.

  4. Molecular identification of Sporothrix species involved in the first familial outbreak of sporotrichosis in the state of Espírito Santo, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Manoel Marques Evangelista Oliveira

    2013-11-01

    Full Text Available Sporotrichosis is a widespread subcutaneous mycosis caused by the dimorphic fungi now known as the Sporothrix schenckii complex. This complex is comprised of at least six species, including Sporothrix albicans, Sporothrix brasiliensis, Sporothrix globosa, Sporothrix luriei, Sporothrix mexicana and S. schenckii. Cases of sporotrichosis have significantly increased in Brazil over the past decade, especially in the state of Rio de Janeiro (RJ, where an epidemic among cat owners has been observed. The zoonotic transmission from cats to humans suggests a common source of infection and indicates that animals can act as vectors. We performed a molecular characterisation of samples collected during the first outbreak of familial sporotrichosis caused by S. brasiliensis in the state of Espírito Santo, Brazil. These results represent the first description of such an outbreak outside the endemic area of zoonotic sporotrichosis in RJ.

  5. Insights into the phylogeny or arylamine N-acetyltransferases in fungi.

    Science.gov (United States)

    Martins, Marta; Dairou, Julien; Rodrigues-Lima, Fernando; Dupret, Jean-Marie; Silar, Philippe

    2010-08-01

    Previous studies have shown that Eumycetes fungi can acylate arylamine thanks to arylamine N-acetyltransferases, xenobiotic-metabolizing enzymes also found in animals and bacteria. In this article, we present the results of mining 96 available fungal genome sequences for arylamine N-acetyltransferase genes and propose their phylogeny. The filamentous Pezizomycotina are shown to possess many putative N-acetyltransferases, whilst these are often lacking in other fungal groups. The evolution of the N-acetyltransferases is best explained by the presence of at least one gene in the opisthokont ancestor of the fungi and animal kingdoms, followed by recurrent gene losses and gene duplications. A possible horizontal gene transfer event may have occurred from bacteria to the basidiomycetous yeast Malassezia globosa.

  6. Superficial fungal infections.

    Science.gov (United States)

    Schwartz, Robert A

    Superficial fungal infections arise from a pathogen that is restricted to the stratum corneum, with little or no tissue reaction. In this Seminar, three types of infection will be covered: tinea versicolor, piedra, and tinea nigra. Tinea versicolor is common worldwide and is caused by Malassezia spp, which are human saprophytes that sometimes switch from yeast to pathogenic mycelial form. Malassezia furfur, Malassezia globosa, and Malassezia sympodialis are most closely linked to tinea versicolor. White and black piedra are both common in tropical regions of the world; white piedra is also endemic in temperate climates. Black piedra is caused by Piedraia hortae; white piedra is due to pathogenic species of the Trichosporon genus. Tinea nigra is also common in tropical areas and has been confused with melanoma.

  7. A Study of the Epiphytic Orchids in Jobolarangan Forest

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    ADIANI VIVIATI

    2001-07-01

    Full Text Available The objective of the research was to know the species of epiphytic orchids in Jobolarangan forest. The orchid samples were taken from all stand-plants. The plants were chosen randomly by considering the diversity and richness of orchids that attach on it. Each plant was sampled in three repetitions. Sampling of orchids existence in the plant’s stand were done using transect method through a zonation system. In this research 11 epiphytic-orchids such as Bulbophyllum bakhuizenii Stenn, Coelogyne miniata Lindl, Coelogyne rochussenii de Vr., Dendrobium bigibbum Lindl., Dendrobchilum longifolium, Eria bogoriensis, J.J.S. Liparis caespitosa (Thou. Lindl., Liparis pallida (Bl.. Pholidota globosa (Bl. Lindl., Polystachya flavescens (Bl. J.J.S., and Trichoglottis sp. were found. The host plant stand that was attached with most orchids was Schefflera fastigiata and Saurauia bracteosa, generally in zone three.

  8. Chlorotic spots on Clerodendrum, a disease caused by a nuclear type of Brevipalpus (Acari:Tenuipalpidae transmitted virus Mancha clorótica do Clerodendrum, uma enfermidade causada por um vírus do tipo nuclear, transmitido pelo ácaro Brevipalpus phoenicis (Acari:Tenuipalpidae

    Directory of Open Access Journals (Sweden)

    Elliot Watanabe Kitajima

    2008-02-01

    Full Text Available Chlorotic spots have been observed in plants of Clerodendrum x speciosum growing in residential gardens and parks in Piracicaba, SP, Brazil. Thin sections of diseased tissues revealed characteristic cytopathic effects of the nuclear type of the Brevipalpus (Acari: Tenuipalpidae mite-transmitted viruses (BTrV. Brevipalpus mites, identified as B. phoenicis, infesting symptomatic C. x speciosum plants transmitted the pathogen to healthy C. x speciosum and to C. thomsonae, Gomphrena globosa, Hibiscus cannabinus, H. coccineus, H. schizopetalus, Salvia leucantha, Spathiphyllum wallasi and Tetragonia expansa causing chlorotic spots on their leaves. Mechanical inoculation using leaf extracts from infected C. x speciosum resulted in chlorotic spots on inoculated C. x speciosum, Chenopodium quinoa, C. amaranticolor, G. globosa, H. cannabinus, H. coccineus and T. expansa leaves. C. amaranticolor and C. quinoa kept at 28 - 30°C became systemically infected. The same cytopathic effects caused by the nuclear type of BTrV were seen in tissues from all infected test plants by electron microscopy. The virus was purified from systemically infected leaves of C. amaranticolor and C. quinoa. A polyclonal antiserum obtained from an immunized rabbit presented a strong reaction with the homologous antigen in ELISA tests. The results suggest that this chlorotic spot disease of C. x speciosum is caused by a new species of the nuclear type of BTrV, tentatively named Clerodendrum chlorotic spot virus (ClCSV.Manchas cloróticas e necróticas foram observadas em folhas de várias plantas de coração-sangrento (Clerodendrum x speciosum cultivadas em parques e jardins em Piracicaba, SP, associadas à infestação pelo ácaro tenuipalpídeo Brevipalpus phoenicis. Exames preliminares de secções de tecido das manchas cloróticas ao microscópio eletrônico revelaram a ocorrência de efeitos citopáticos característicos dos induzidos pelos vírus do tipo nuclear, transmitido

  9. Evolution of phytoplankton cultures after ultraviolet light treatment

    International Nuclear Information System (INIS)

    Martínez, L.F.; Mahamud, M.M.; Lavín, A.G.; Bueno, J.L.

    2012-01-01

    Introducing invasive species in new environments through ballast water is a specific problem of contamination and has recently become one of the main concerns of Maritime Organizations. Ultraviolet-C radiation (UV-C) is a technological alternative to prevent this maritime pollution. This study addresses the effect of UV-C on different phytoplankton cultures and also the ability to recover following exposure to damage. A UV-C low-pressure lamp irradiates the cultures. The distance from the source and the thickness of the layer prevent part of the energy from reaching the culture and the disinfective process is diminished. Some cultures such as Chlorella autotrophica and Chaetoceros calcitrans can easily recover from UV-C damage. However, Phaeocystis globosa does not have this ability. C. calcitrans forms cysts and exhibits two different behaviours depending on the dose applied.

  10. Abundance and size structure of planktonic protist communities in a Neotropical floodplain: effects of top-down and bottom-up controls

    Directory of Open Access Journals (Sweden)

    Bianca Ramos de Meira

    2017-12-01

    Full Text Available Abstract: Aim: We aimed to assess the influence of bottom-up and top-down control mechanisms on the abundance and size structure of protist communities (heterotrophic flagellates and ciliates. We formulated the following hypothesis: bottom-up control mechanisms, related to the availability of resources in the environment, are responsible for structuring the abundance of these communities, whereas top-down control mechanisms, related to predation effects, determine the size pattern of these organisms. Methods Samples for planktonic organisms were taken in 20 shallow lakes belonging to the upper Paraná River floodplain. We evaluated linear regression models to select the best model which predicts the patterns observed according to Akaike Information Criterion. Results The best models selected to explain the abundance of heterotrophic flagellates included negative relations with picophytoplankton abundance and positive with rotifers abundance, while for their size structure, negative relationships were found with heterotrophic bacteria, ciliates and rotifers biovolumes. In relation to the ciliates, their abundances were positively related to the rotifers and picophytoplankton abundances and negatively with the heterotrophic bacteria abundance. On the other hand, for the size structure, the best models selected strong negative relations with the microcrustaceans biovolumes, in addition to relations with the different fractions of the phytoplankton. Conclusion For both flagellates and ciliates, their abundance is being mainly regulated by a bottom up control mechanism, whereas for the size structure the results showed that both food resources and predators were important, indicating that bottom-up and top-down mechanisms act simultaneously in determining the size of these microorganisms.

  11. Hourly Activity and Natural Infection of Sandflies (Diptera: Psychodidae) Captured from the Aphotic Zone of a Cave, Minas Gerais State, Brazil

    Science.gov (United States)

    Carvalho, Gustavo Mayr de Lima; Brazil, Reginaldo Peçanha; Saraiva, Lara; Quaresma, Patrícia Flávia; Botelho, Helbert Antônio; Ramos, Mariana Campos das Neves Farah; de Almeida Zenóbio, Ana Paula Lusardo; e Meira, Paula Cavalcante Lamy Serra; de Castilho Sanguinette, Cristiani; Filho, José Dilermando Andrade

    2012-01-01

    Sandflies are holometabolous insects that are of great epidemiological importance in the neotropical region as vectors of leishmaniases. Caves are ecotopes that significantly differ from external environments and, among the insects that live or visit their internal area and adjacent environment, sandflies are commonly found. Based on this context, the objective of this work was to examine the period of activity of sandflies in the cave environment in the aphotic zone. Thus, four sandfly captures were conducted, one in each season of the year, in a cave where studies on the bioecological aspects of sandfly fauna have been conducted since 2008. In this same study, we have also noticed the presence of flagellates in some captured females. Catches were carried out for 24 hours using a Shannon trap, light bait, and cave walls were actively searched. We collected a total of 638 sandflies, representing 11 species. The most abundant species and with more intense period of activity were, in descending order: Lu. cavernicola (62%), Ev. spelunca (16%) and Ev. sallesi (14%). A total of 69 females were dissected to check for natural infection, and in five specimens we found living flagellated forms: two Ev. spelunca, two Ev. sallesi and one Sc. sordellii. This study shows that the activity of some species caught in the aphotic zone of the cave, especially Lu. cavernicola, differs from what has already been reported in previous sandfly captures, which are almost always conducted at night and during twilight. The existence of sandflies that were naturally infected with flagellates and the lack of awareness regarding the behaviour of sandflies in cave environments are strong indicators of the need for further study on this group of insects in this ecotope, as a safety measure to protect the visitors of such environment. PMID:23284957

  12. Selenium Uptake and Volatilization by Marine Algae

    Science.gov (United States)

    Luxem, Katja E.; Vriens, Bas; Wagner, Bettina; Behra, Renata; Winkel, Lenny H. E.

    2015-04-01

    Selenium (Se) is an essential trace nutrient for humans. An estimated one half to one billion people worldwide suffer from Se deficiency, which is due to low concentrations and bioavailability of Se in soils where crops are grown. It has been hypothesized that more than half of the atmospheric Se deposition to soils is derived from the marine system, where microorganisms methylate and volatilize Se. Based on model results from the late 1980s, the atmospheric flux of these biogenic volatile Se compounds is around 9 Gt/year, with two thirds coming from the marine biosphere. Algae, fungi, and bacteria are known to methylate Se. Although algal Se uptake, metabolism, and methylation influence the speciation and bioavailability of Se in the oceans, these processes have not been quantified under environmentally relevant conditions and are likely to differ among organisms. Therefore, we are investigating the uptake and methylation of the two main inorganic Se species (selenate and selenite) by three globally relevant microalgae: Phaeocystis globosa, the coccolithophorid Emiliania huxleyi, and the diatom Thalassiosira oceanica. Selenium uptake and methylation were quantified in a batch experiment, where parallel gas-tight microcosms in a climate chamber were coupled to a gas-trapping system. For E. huxleyi, selenite uptake was strongly dependent on aqueous phosphate concentrations, which agrees with prior evidence that selenite uptake by phosphate transporters is a significant Se source for marine algae. Selenate uptake was much lower than selenite uptake. The most important volatile Se compounds produced were dimethyl selenide, dimethyl diselenide, and dimethyl selenyl sulfide. Production rates of volatile Se species were larger with increasing intracellular Se concentration and in the decline phase of the alga. Similar experiments are being carried out with P. globosa and T. oceanica. Our results indicate that marine algae are important for the global cycling of Se

  13. The Effect of Aqueous and Ethanolic Extracts of Teucrium polium on Candida Albicans and Two Species of Malassezia

    Directory of Open Access Journals (Sweden)

    Maryam Nadimi

    2013-08-01

    Full Text Available Background: Teucrium polium L. is a medicinal plant, which due to its antimicrobial, antispasmodic and anti-tumor properties has been used in traditional medicine for over 2000 years. The aim of this research was to study the effect of aqueous and ethanolic extracts of Teucrium polium L. against three strains of Candida albicans (ATCC 62061, ATCC 1677, and NCPF 3153, Malassezia furfur and Malassezia globosa using pour plate method. Materials and Methods: Teucrium polium L. was collected from Broojen area during the spring. The plant was dried and powdered. The aqueous and ethanolic extracts were prepared from the fine powder. Different concentrations of extracts (1, 2, 4, and 8 mg/ml were made in Sabouraud Dextrose Agar (SDA and modified Leeming-Notman Agar (MLNA medium for Candida albicans, Malassezia furfur and Malassezia globosa. 1.5×106 cfu/ml of yeasts, were cultured on media and incubated at 37ºC and 32ºC respectively. Pour plate method was used to assess the antifungal activity of these extracts.Results: The inhibitory effect of ethanolic extract of Teucrium polium L. on the three strains of Candida albicans was depended on concentration level of extracts in media. Aqueous extract had inhibitory effect on Candida albicans (NCPF 3153 only, and with increasing of the extract concentration, the number of colonies was decreased, so that in concentration of 8 mg/ml, no growth was seen. Aqueous and ethanolic extracts had no inhibitory effect on Malassezia species. Conclusion: Teucrium polium L. extracts have considerable inhibitory effect on different strains of Candida albicans. Further investigations are needed to detect the effectiveness of this plant in treatment of Candida infections.

  14. Detection of Malassezia Species Isolated From Patients With Pityriasis Versicolor and Seborrheic Dermatitis Using Nested-PCR

    Directory of Open Access Journals (Sweden)

    Zarei Mahmoudabadi

    2014-12-01

    Full Text Available Background The species of the genus Malassezia are lipophilic and dimorphic yeasts that are regarded as part of the normal flora of the skin of humans and warm-blooded animals. These organisms are the cause of superficial mycosis in humans and other animals, and are common in pityriasis versicolor and seborrheic dermatitis. Objectives The purpose of this study was to determine the frequency of common Malassezia species in patients affected by pityriasis versicolor and seborrheic dermatitis using of the nested PCR method, in the city of Ahvaz. Patients and Methods In the present study, 85 samples from patients with pityriasis versicolor and seborrheic dermatitis were analyzed by the nested-PCR method. During the first stage, the internal transcribed spacer (ITS region from the ribosomal DNA was reproduced using primers ITS4-R and ITS1F-N. During the second stage, the product of the first step was used as DNA and using three special primer pairs, including Mf-F, 5.8SR and M.gl-F, 5.8SR and M.rt-F and M.rt-R, the inner part of the first phase was detected. Results The most common isolate was Malassezia furfur (51.3% followed by M. globosa (35.2% and M. restricta (13.5%. Amongst the 30 patients with seborrheic dermatitis, in 15 cases (65.2% M. restricta, in six cases (26.1% M. globosa and in two cases (8.7% M. furfur was detected and in seven patients no isolate was detected. Conclusions The nested-PCR is a rapid and repeatable method for identification of important Malassezia species and this method is recommended for use on more patients. In addition the most common agents of pityriasis versicolor and seborrheic dermatitis were M. furfur and M. restricta, respectively.

  15. Molecular Diagnosis of Pathogenic Sporothrix Species.

    Directory of Open Access Journals (Sweden)

    Anderson Messias Rodrigues

    2015-12-01

    Full Text Available Sporotrichosis is a chronic (subcutaneous infection caused by thermodimorphic fungi in the order, Ophiostomatales. These fungi are characterized by major differences in routes of transmission, host predilections, species virulence, and susceptibilities to antifungals. Sporothrix species emerge in the form of outbreaks. Large zoonoses and sapronoses are ongoing in Brazil and China, respectively. Current diagnostic methods based on morphology and physiology are inaccurate due to closely related phenotypes with overlapping components between pathogenic and non-pathogenic Sporothrix. There is a critical need for new diagnostic tools that are specific, sensitive, and cost-effective.We developed a panel of novel markers, based on calmodulin (CAL gene sequences, for the large-scale diagnosis and epidemiology of clinically relevant members of the Sporothrix genus, and its relative, Ophiostoma. We identified specific PCR-based markers for S. brasiliensis, S. schenckii, S. globosa, S. mexicana, S. pallida, and O. stenoceras. We employed a murine model of disseminated sporotrichosis to optimize a PCR assay for detecting Sporothrix in clinical specimens.Primer-BLAST searches revealed candidate sequences that were conserved within a single species. Species-specific primers showed no significant homology with human, mouse, or microorganisms outside the Sporothrix genus. The detection limit was 10-100 fg of DNA in a single round of PCR for identifying S. brasiliensis, S. schenckii, S. globosa, S. mexicana, and S. pallida. A simple, direct PCR assay, with conidia as a source of DNA, was effective for rapid, low-cost genotyping. Samples from a murine model of disseminated sporotrichosis confirmed the feasibility of detecting S. brasiliensis and S. schenckii DNA in spleen, liver, lungs, heart, brain, kidney, tail, and feces of infected animals.This PCR-based method could successfully detect and identify a single species in samples from cultures and from clinical

  16. Molecular Diagnosis of Pathogenic Sporothrix Species

    Science.gov (United States)

    Rodrigues, Anderson Messias; de Hoog, G. Sybren; de Camargo, Zoilo Pires

    2015-01-01

    Background Sporotrichosis is a chronic (sub)cutaneous infection caused by thermodimorphic fungi in the order, Ophiostomatales. These fungi are characterized by major differences in routes of transmission, host predilections, species virulence, and susceptibilities to antifungals. Sporothrix species emerge in the form of outbreaks. Large zoonoses and sapronoses are ongoing in Brazil and China, respectively. Current diagnostic methods based on morphology and physiology are inaccurate due to closely related phenotypes with overlapping components between pathogenic and non-pathogenic Sporothrix. There is a critical need for new diagnostic tools that are specific, sensitive, and cost-effective. Methodology We developed a panel of novel markers, based on calmodulin (CAL) gene sequences, for the large-scale diagnosis and epidemiology of clinically relevant members of the Sporothrix genus, and its relative, Ophiostoma. We identified specific PCR-based markers for S. brasiliensis, S. schenckii, S. globosa, S. mexicana, S. pallida, and O. stenoceras. We employed a murine model of disseminated sporotrichosis to optimize a PCR assay for detecting Sporothrix in clinical specimens. Results Primer-BLAST searches revealed candidate sequences that were conserved within a single species. Species-specific primers showed no significant homology with human, mouse, or microorganisms outside the Sporothrix genus. The detection limit was 10–100 fg of DNA in a single round of PCR for identifying S. brasiliensis, S. schenckii, S. globosa, S. mexicana, and S. pallida. A simple, direct PCR assay, with conidia as a source of DNA, was effective for rapid, low-cost genotyping. Samples from a murine model of disseminated sporotrichosis confirmed the feasibility of detecting S. brasiliensis and S. schenckii DNA in spleen, liver, lungs, heart, brain, kidney, tail, and feces of infected animals. Conclusions This PCR-based method could successfully detect and identify a single species in samples

  17. Identification and speciation of Malassezia in patients clinically suspected of having pityriasis versicolor

    Directory of Open Access Journals (Sweden)

    Avani Shah

    2013-01-01

    Full Text Available Background: Malassezia is a lipid-dependent yeast known to cause Pityriasis versicolor, a chronic, recurrent superficial infection of skin and present as hypopigmented or hyperpigmented lesions on areas of skin. If not diagnosed and treated, it may lead to disfigurement of the areas involved and also result in deep invasive infections. Aim: The aim of the present study was to identify and speciate Malassezia in patients clinically suspected of having Pityriasis versicolor. Materials and Methods: Total 139 patients suspected of having Pityriasis versicolor were evaluated clinically and diagnosis was done by Wood′s lamp examination, confirmed mycologically by using KOH, cultivation on Sabouraud′s dextrose agar and modified Dixon agar at a tertiary care hospital in Mumbai. The total duration of study was 12 months. Results: Majority of the patients were males (59.71% in the age group of 21-30 years (33.81% who were students (30.21% by profession. The incidence of Malassezia in Pityriasis versicolor was 50.35%. The most common isolate was M. globosa (48.57%, followed by M. furfur (34.28%. Majority of the patients had hypopigmented lesions, with M. globosa as the predominant isolate. Neck was the most common site affected; 88.48% were Wood′s lamp positive of which 56.91% of Malassezia isolates grew on culture. KOH mount was positive in 82.01% of which 61.40% Malassezia isolates grew on culture. Conclusions: The procedure of culture and antifungal testing is required to be performed as different species of Malassezia are involved in Pityriasis versicolor and susceptibility is different among different species. Thus, it would help to prevent recurrences and any systemic complications.

  18. Novel and known constituents from Buddleja species and their activity against leukocyte eicosanoid generation.

    Science.gov (United States)

    Liao, Y H; Houghton, P J; Hoult, J R

    1999-09-01

    We have undertaken a systematic survey of the genus Buddleja used in traditional Chinese medicine for antiinflammatory and other indications by testing extracts and isolated natural products for their activity against the enzymes of the arachidonate cascade. This was done by using elicited rat peritoneal leukocytes, a physiologically relevant established whole cell system that expresses both cyclo-oxygenase (COX) and 5-lipoxygenase (5-LOX) activity. Lipophilic extracts of B. globosa roots and B. myriantha stem exhibited inhibitory activities in the 5-LOX and COX enzyme assays, whereas those of B. officinalis flowers, B. yunanesis stems, and B. asiatica stems showed inhibitory activities only against COX. The phytochemical investigation of these extracts, and consequent structure elucidation of isolated compounds using spectroscopic data, led to the isolation from B. globosa of three new terpenoid compounds named dihydrobuddledin A, buddledone A, and buddledone B and four known compounds-buddledins A, B, and C and zerumbone; 12 known compounds from B. officinalis-calceolarioside, campneoside, verbascoside, echinacoside, forsythoside B, angoroside A, crocetin monogentibiosyl ester, acacetin, acacetin-7-O-alpha-L-rhamnopyranosyl (1-6)-beta-D-glucopyranoside, acacetin-7-O-alpha-L-rhamnopyranosyl (1-6)[alpha-L-rhamnopyranosyl (1-2)]-beta-D-glucopyranoside, songarosaponin A, delta-amyrone; and eight known compounds fromB. yunanesis-11,14-dihydroxy-8,11, 13-abietatrien-7-one, beta-sitosterol, verbascoside, echinacoside, forsythoside B, angoroside A, methylcatapol, and sucrose. Tests on the isolated compounds for inhibition of eicosanoid synthesis showed that buddledin A, crocetin monogentibiosyl ester, and acacetin exhibited an inhibitory effect on COX with IC(50) values of 13.7 microM, 28.2 microM, and 77.5 microM, respectively, whereas buddledin A exhibited inhibitory effect on 5-LOX with an IC(50) value of 50.4 microM.

  19. Maximum growth rates and possible life strategies of different bacterioplankton groups in relation to phosphorus availability in a freshwater reservoir

    Czech Academy of Sciences Publication Activity Database

    Šimek, Karel; Horňák, Karel; Jezbera, Jan; Nedoma, Jiří; Vrba, Jaroslav; Straškrábová, Viera; Macek, Miroslav; Dolan, J. R.; Hahn, M.W.

    2006-01-01

    Roč. 8, č. 9 (2006), s. 1613-1624 ISSN 1462-2912 R&D Projects: GA ČR(CZ) GA206/05/0007; GA AV ČR(CZ) 1QS600170504 Grant - others:MŠM(CZ) 60076658/01 Institutional research plan: CEZ:AV0Z60170517 Keywords : bacterioplankton community composition * growth of bacteria and flagellates * phosphorus availability * reservoir * top-down and bottom-up control Subject RIV: EE - Microbiology, Virology Impact factor: 4.630, year: 2006

  20. Description of a bacterium associated with redmouth disease of rainbow trout (Salmo gairdneri)

    Science.gov (United States)

    Ross, A.J.; Rucker, R.R.; Ewing, W.H.

    1966-01-01

    A description was given of a gram-negative, peritrichously flagellated, fermentative bacterium that was isolated on numerous occasions from kidney tissues of rainbow trout (Salmo gairdneri) afflicted with redmouth disease. Although the bacteria apparently were members of the family Enterobacteriaceae, it was impossible to determine their taxonomic position within the family with certainty. Hence it was recommended that their taxonomic position remain sub judice for the present. As a temporary designation RM bacterium was used. Redmouth disease was transmitted from infected to normal fish through the medium of water.

  1. Population dynamics of active and total ciliate populations in arable soil amended with wheat

    DEFF Research Database (Denmark)

    Ekelund, F.; Frederiksen, Helle B.; Ronn, R.

    2002-01-01

    of the population may be encysted. The factors governing the dynamics of active and encysted cells in the soil are not well understood. Our objective was to determine the dynamics of active and encysted populations of ciliates during the decomposition of freshly added organic material. We monitored, in soil...... microcosms, the active and total populations of ciliates, their potential prey (bacteria and small protozoa), their potential competitors (amoebae, flagellates, and nematodes), and their potential predators (nematodes). We sampled with short time intervals (2 to 6 days) and generated a data set, suitable...

  2. Fuentes proteínicas no tradicionales y su efecto sobre el crecimiento y supervivencia, durante la masculinización del pez Cichlasoma urophthalmus (Perciformes: Cichlidae)

    OpenAIRE

    Cuenca-Soria, Carlos A.; Navarro Angulo, Leonardo I.; Castillo-Domínguez, Alfonso; Melgar Valdes, Carolina E.; Pérez-Palafox, Xchel A.; Ortiz-Hernández, Mateo

    2016-01-01

    ResumenEn el sureste de México, la acuicultura se ha visto seriamente afectada por los altos costos de los alimentos comerciales. Como parte de la búsqueda de alimentos no tradicionales, probamos el pez de agua dulce Astyanax aeneus y el caracol Pomacea flagellata como posibles fuentes de proteínas para Cichlasoma urophthalmus. Aplicamos la hormona androgénica fluoximesterona durante 45 días. Un kilogramo de dieta experimental (P. flagellate/A. aeneus) y uno de los alimentos comerciales se ro...

  3. Nontraditional protein sources and their effect on growth and survival, during masculinization, of the fish Cichlasoma urophthalmus (Perciformes: Cichlidae)

    OpenAIRE

    Cuenca-Soria, Carlos A.; Navarro Angulo, Leonardo I.; Castillo-Domínguez, Alfonso; Melgar Valdes, Carolina E.; Pérez-Palafox, Xchel A.; Ortiz-Hernández, Mateo

    2016-01-01

    In Southeastern Mexico, aquaculture has been seriously affected by the high costs of commercial food. As part of the search for alternative foods we tested the freshwater fish Astyanax aeneus and the snail Pomacea flagellata as possible protein sources for Cichlasoma urophthalmus. We applied fluoxymesterone androgenic hormone for 45 days. One kilogram of experimental food (P. flagellate/A. aeneus) and one of commercial food were sprayed with solution of fluoxymesterone/absolute ethanol, at 5m...

  4. Sloth biology: an update on their physiological ecology, behavior and role as vectors of arthropods and arboviruses

    Directory of Open Access Journals (Sweden)

    Gilmore D.P.

    2001-01-01

    Full Text Available This is a review of the research undertaken since 1971 on the behavior and physiological ecology of sloths. The animals exhibit numerous fascinating features. Sloth hair is extremely specialized for a wet tropical environment and contains symbiotic algae. Activity shows circadian and seasonal variation. Nutrients derived from the food, particularly in Bradypus, only barely match the requirements for energy expenditure. Sloths are hosts to a fascinating array of commensal and parasitic arthropods and are carriers of various arthropod-borne viruses. Sloths are known reservoirs of the flagellate protozoan which causes leishmaniasis in humans, and may also carry trypanosomes and the protozoan Pneumocystis carinii.

  5. Effect of enhanced UV-B radiation on motile microorganisms

    International Nuclear Information System (INIS)

    Haeder, D.P.

    1985-02-01

    The effect of slightly increased UV-B radiation was studied in four taxonomically very different microorganisms: the gliding prokaryotic cyanobacterium, Phormidium, the unicellular green alga Cosmarium, the flagellate Euglena and the cellular slime mold Dictyostelium. UV-B doses which can be expected as a result of a slight decrease of the protective ozone layer in the stratosphere, do not kill or damage the microorganisms visibly. However, such UV-B doses impair the development, motility and photoorientation of these organisms. Due to the inhibition of these physiological important parameters the organisms cannot respond adequately to the changing factors in their environment, which prevents the survival of the populations. (orig.) [de

  6. Phytoplankton aggregate formation: observations of patterns and mechanisms of cell sticking and the significance of exopolymeric material

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Hansen, Jorgen L. S.

    1993-01-01

    are sticky in themselves, and coagulation depends on cell-cell sticking and does not involve mucus. Aggregates are composed solely of cells. Cells of the diatom Chaetoceros affinis, on the other hand, are not in themselves sticky. Transparent exopolymeric particles (TEP), produced by the diatom, cause...... the cells to aggregate and coagulation depends on TEP-cell rather than cell-cell sticking. Aggregates are formed of a mixture of mucus and cells. We found several species of diatoms and one flagellate species to produce copious amounts of TEP. TEP from some species (e.g. Coscinodiscus sp.) is sticky and may...

  7. Grazer and virus-induced mortality of bacterioplankton accelerates development of .i.Flectobacillus./i. populations in a freshwater community

    Czech Academy of Sciences Publication Activity Database

    Šimek, Karel; Weinbauer, M.G.; Horňák, Karel; Jezbera, Jan; Nedoma, Jiří; Dolan, J. R.

    2007-01-01

    Roč. 9, č. 3 (2007), s. 789-800 ISSN 1462-2912 R&D Projects: GA ČR(CZ) GA206/05/0007; GA AV ČR(CZ) 1QS600170504 Grant - others:MŠMT(CZ) Barrande 2004-004-2 Institutional research plan: CEZ:AV0Z60170517 Source of funding: V - iné verejné zdroje Keywords : bacterioplankton community composition * virus lysis * flagellate bacterivory * reservoir * FISH analysis of food vacuoles * microautoradiography Subject RIV: EE - Microbiology, Virology Impact factor: 4.929, year: 2007

  8. 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.

  9. Alternative leech vectors for frog and turtle trypanosomes.

    Science.gov (United States)

    Siddall, M E; Desser, S S

    1992-06-01

    Trypanosoma pipientis infections were achieved by exposing laboratory-raised bullfrog tadpoles (Rana catesbeiana) to the leech Desserobdella picta that had fed on infected frogs. Likewise, a laboratory-raised snapping turtle (Chelydra serpentina) was infected with Trypanosoma chrysemydis following exposure to infected Placobdella ornata. Transmission of the trypanosomes by these leeches constitutes new vector records for the parasites. The biology of D. picta and P. ornata suggests that they are more important in transmitting these flagellates than the species of leech previously reported as vectors.

  10. Hematophagous insects as vectors for frog trypanosomes.

    Science.gov (United States)

    Ramos, B; Urdaneta-Morales, S

    1977-12-01

    Experimental infections of three hematophagous arthropods (Rhodnius prolixus, Aedes aegypti, and Culex pipiens) with a trypanosome of the Trypanosoma rotatorium complex found in the frogs Hyla crepitans and Leptodactylus insularum revealed that A. aegypti is a good host for the flagellate; the course of development in the intestinal tract of the mosquito is described from 15 minutes to 168 hours. C. pipiens showed only low intestinal infections and R. prolixus did not permit development of the parasite. It is postulated that, in addition to the transmission of T. rotatorium by leeches, batrachophilic mosquitoes may transmit the parasite to frogs of more terrestrial habits by being ingested by these anurans.

  11. New thermophilic anaerobes that decompose crystalline cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Taya, M; Hinoki, H; Suzuki, Y; Yagi, T; Yap, M G.S.; Kobayashi, T

    1985-01-01

    Two strains (designated as 25A and 3B) of cellulolytic, thermophilic, anaerobic, spore-forming bacteria were newly isolated from an alkaline hot spring through enrichment cultures at 60/sup 0/C. Though strain 25A was nearly identical to Clostridium thermocellum ATCC 27405 as a reference strain, strain 3B had some characteristics different from the reference; no flagellation, alkalophilic growth property (optimum pH of 7.5-8) and orange-colored pigmentation of the cell mass. Strain 3B effectively decomposed micro-crystalline cellulose (Avicel) and raw cellulosics (rice straw, newspaper, and bagasse) without physical or chemical pretreatments. 20 references, 2 figures, 2 tables.

  12. Ecological studies on algae isolated from the effluents of an oil refinery, a fertilizer factory and a brewery

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, H D [Banarus Hindu Univ.; Bisaria, G P; Bhandari, L M; Rana, B C; Sharma, V

    1974-07-01

    Tha algal flora and physico-chemical characteristics of the effluents of the Indian Oil Refinery, Barauni; the Sindri Fertilizer Factory, Sindri; and the Mohan Meakin Brewery, Ghaziabad were studied. The studies indicate that algae can tolerate and grow in highly polluted waters. The blue-green algae, flagellates and euglenoids are mostly associated with organically rich effluents, low in dissolved oxygen, whereas waters rich in nitrogenous compounds favor the growth of green algae, e.g., Chlorella. A combination of algal and chemical characteristics may be successfully employed to evaluate the water quality of a given habitat.

  13. Soil fauna communities and microbial respiration in high Arctic tundra soils at Zackenberg, Northeast Greenland

    DEFF Research Database (Denmark)

    Sørensen, Louise I.; Holmstrup, Martin; Maraldo, Kristine

    2006-01-01

    The soil fauna communities were described for three dominant vegetation types in a high arctic site at Zackenberg, Northeast Greenland. Soil samples were extracted to quantify the densities of mites, collembolans, enchytraeids, diptera larvae, nematodes and protozoa. Rates of microbial respiration...... densities (naked amoeba and heterotrophic flagellates) were equal. Respiration rate of unamended soil was similar in soil from the three plots. However, a higher respiration rate increase in carbon + nutrient amended soil and the higher densities of soil fauna (with the exception of mites and protozoa...

  14. New Scenarios of Chagas Disease Transmission in Northern Colombia

    Directory of Open Access Journals (Sweden)

    Catalina Tovar Acero

    2017-01-01

    Full Text Available Chagas disease (CD is a systemic parasitic infection caused by the flagellated form of Trypanosoma cruzi. Córdoba department, located in the Colombian Caribbean Coast, was not considered as a region at risk of T. cruzi transmission. In this article, we describe the first acute CD case in Salitral village in Sahagún, Córdoba, confirmed by microscopy and serological tests. Our results draw attention to a new scenario of transmission of acute CD in nonendemic areas of Colombia and highlight the need to include CD in the differential diagnosis of febrile syndromes in this region.

  15. Induction of phospholipase- and flagellar synthesis in Serratia liquefaciens is controlled by expression of the flagellar master operon flhD

    DEFF Research Database (Denmark)

    Givskov, M; Eberl, L; Christiansen, Gunna

    1995-01-01

    . Expression of flagella is demonstrated to follow a growth-phase-dependent pattern. Cloning, complementation studies and DNA-sequencing analysis has identified a genetic region in Serratia liquefaciens which exhibits extensive homology to the Escherichia coli flhD flagellar master operon. Interruption...... of the chromosomal flhD operon in S. liquefaciens results in non-flagellated and phospholipase-negative cells, but the synthesis of other exoenzymes is not affected. By placing the flhD operon under the control of a foreign inducible promoter we have shown that increased transcription through the flhD operon leads...

  16. Herpetomonas spp. isolated from tomato fruits (Lycopersicon esculentum) in southern Spain.

    Science.gov (United States)

    Marín, Clotilde; Fabre, Sandrine; Sánchez-Moreno, Manuel; Dollet, Michel

    2007-05-01

    A flagellate of the family Trypanosomatidae was isolated from fruits of Lycopersicon esculentum (tomato) in southeastern Spain. The isolate was successfully adapted to in vitro culture in monophasic media. The morphology showed the kinetoplast to be positioned towards the middle of the body, and the typical opistomastigote form characteristic of members of the genus Herpetomonas. Amplification of the mini-exon gene was negative, whilst for the 5S ribosomal rRNA gene the result was positive. The DNA sequence was obtained and its alignment with other trypasomatids, obtained using the BLAST algorithm, suggested it was closely related to Herpetomonas samuelpessoai.

  17. Numerical Analysis of Small Deformation of Flexible Helical Flagellum of Swimming Bacteria

    Science.gov (United States)

    Takano, Yasunari; Goto, Tomonobu

    Formulations are conducted to numerically analyze the effect of flexible flagellum of swimming bacteria. In the present model, a single-flagellate bacterium is assumed to consist of a rigid cell body of the prolate spheroidal shape and a flexible flagellum of the helical form. The resistive force theory is applied to estimate the force exerted on the flagellum. The torsional as well as the bending moments determine the curvature and the torsion of the deformed flagellum according to the Kirchhoff model for an elastic rod. The unit tangential vector along the deformed flagellum is calculated by applying evolution equations for space curves, and also a deformed shape of the flagellum is obtained.

  18. Papposphaera obpyramidalis (Haptophyta, Papposphaeraceae): New findings from both Polar Regions

    DEFF Research Database (Denmark)

    Thomsen, Helge Abildhauge; Egge, Jorun Karin; Heldal, Mikal

    2016-01-01

    Papposphaera obpyramidalis is reinvestigated based on additional high latitude sampling from the southern hemisphere. The material used here comprises better preserved transmission electron microscope (TEM) material including several cells with complete flagellation, as well as light microscopy (....... However, here we present also findings of the species from Arctic realms based on recent SEM surveys from the Svalbard region, indicating a bipolar distribution.......) of living material. The re-examination basically confirms the findings that were part of the species description but also adds details on, for example, nutritional mode and the presence of an underlayer of unmineralized scales. P. obpyramidalis has hitherto been considered confined to Antarctic waters...

  19. Biological processes in the North Sea: comparison of Calanus helgolandicus and Calanus finmarchicus vertical distribution and production

    DEFF Research Database (Denmark)

    Jonasdottir, Sigrun; Koski, Marja

    2011-01-01

    stratified with a tidally generated deep chlorophyll maximum at 30 m depth. When co-occurring, a separation of the species was evident, where C. finmarchicus preferred colder (9°C) deeper waters, while C. helgolandicus stayed in the warmer (16°C) surface waters. Egg production rates (EPRs) were...... not statistically different between the species, and the population egg production depended primarily on female abundance and was generally higher for C. finmarchicus. EPRs of the Calanus spp. were best explained by the abundance of autotrophic and heterotrophic dinoflagellates, flagellates and ciliates. Hatching...

  20. Food selection by bacterivorous protists: insight from the analysis of the food vacuole content by means of fluorescence in situ hybridization

    Czech Academy of Sciences Publication Activity Database

    Jezbera, Jan; Horňák, Karel; Šimek, Karel

    2005-01-01

    Roč. 52, č. 3 (2005), s. 351-363 ISSN 0168-6496. [Symposium on Aquatic Microbial Ecology /9./. Helsinky, 21.08.2005-26.08.2005] R&D Projects: GA ČR(CZ) GA206/02/0003; GA ČR(CZ) GA206/05/0007 Grant - others:MŠMT(CZ) 1058/2004 Institutional research plan: CEZ:AV0Z60170517 Keywords : hybridization * grazing * flagellates Subject RIV: DA - Hydrology ; Limnology Impact factor: 2.787, year: 2005

  1. Rôle fonctionnel des protistes hétéro/mixotrophes dans le réseau trophique d'un écosystème conchylicole: le marais atlantique

    OpenAIRE

    Dupuy, Christine

    1999-01-01

    L'huître Crassostrea gigas se nourrit en filtrant le phytoplancton, mais dans les marais atlantiques, cette production phytoplanctonique ne suffit pas pour équilibrer son bilan énergétique. L'analyse du réseau microbien planctonique au cours de l'isolement du marais en mortes-eaux montre une succession de peuplements : des diatomées qui épuisent rapidement les nutriments, puis des bactéries et enfin des protistes flagellés et ciliés. La production bactérienne représente une ressource énergéti...

  2. The secondary structure of large-subunit rRNA divergent domains, a marker for protist evolution

    DEFF Research Database (Denmark)

    Lenaers, G; Nielsen, Henrik; Engberg, J

    1988-01-01

    The secondary structure of the large-subunit ribosomal RNA (24-26S rRNA) has been studied with emphasis on comparative analysis of the folding patterns of the divergent domains in the available protist sequences, that is Prorocentrum micans (dinoflagellate), Saccharomyces carlsbergensis (yeast......), Tetrahymena thermophila (ciliate), Physarum polycephalum and Dictyostelium discoideum (slime moulds), Crithidia fasciculata and Giardia lamblia (parasitic flagellates). The folding for the D3, D7a and D10 divergent domains has been refined and a consensus model for the protist 24-26S rRNA structure...

  3. Inactivation of Giardia muris cysts by free chlorine.

    OpenAIRE

    Leahy, J G; Rubin, A J; Sproul, O J

    1987-01-01

    The chlorine resistance of cysts of the flagellate protozoan Giardia muris was examined. This organism, which is pathogenic to mice, is being considered as a model for the inactivation of the human pathogen Giardia lamblia. Excystation was used as the criterion for cyst viability. Experiments were performed at pH 5, 7, and 9 at 25 degrees C and pH 7 at 5 degrees C. Survival curves were "stepladder"-shaped, but concentration-time data generally conformed to Watson's Law. Chlorine was most effe...

  4. [Spread of hemoparasites in reptiles and amphibians in Italy].

    Science.gov (United States)

    Ricci, M

    1999-12-01

    Hemoparasites were harvested from 993 individuals belonging to 15 reptilian and 1 amphibian species, from various Italian localities. Hemogregarins were found in 10 reptilian species while a flagellate and microfilariae were found only in Tarentola mauritanica from Lampedusa. For each host species and place of origin the frequencies of hemogregarins are reported and discussed. Longitudinal studies with periodical thin smears were carried out on 5 Tarentola mauritanica, 4 Lacerta viridis, 26 Podarcis filfolensis, 10 Podarcis muralis, 38 Podarcis sicula, 8 Chalcides ocellatus. This material, whose study has not yet been completed, is made available by the author who strongly encourages further investigations on this subject.

  5. An overview on the ecology of Triatominae (Hemiptera:Reduviidae).

    Science.gov (United States)

    Galvão, Cleber; Justi, Silvia A

    2015-11-01

    Chagas disease, the American trypanosomiasis, is an important neglected tropical illness caused by the flagellate protozoan Trypanosoma cruzi (Kinetoplastida, Trypanosomatidae) and transmitted by insects of the subfamily Triatominae (Hemiptera: Reduviidae). Here we provide an overview on the current knowledge about Triatominae ecology, its association with human, T. cruzi infection and the immediate consequences of habitat fragmentation. We also discuss the geographic distribution of the species and the importance of predicting their distributions to control programs. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Ultrastructural study of spermatogenesis in Phoronopsis harmeri (Lophophorata, Phoronida)

    Science.gov (United States)

    Reunov, Arkadiy; Klepal, Waltraud

    2004-02-01

    The process of sperm development in Phoronopsis harmeri was studied by electron microscopy. Developing spermatogenical cells are aggregated around the capillaries of the haemal plexus. The spermatogonia, which are situated around the capillary walls of the caeca, are remarkable for the presence of germ-line vesicles and contain their centrioles near the cell membrane. The spermatocytes and spermatids are flagellated cells arranged in clusters. During spermiogenesis the basal body/flagellum complex migrates to the apical pole of the spermatid. The acrosome-like structure arises from material produced by the Golgi complex. It lacks a surrounding membrane and has a fibrillar content. The nucleus elongates and the condensation of chromatin is caused by an activation of 'initiation centres'. The late spermatid and the spermatozoon appear as two-armed 'V'-shaped cells in which one arm contains the nucleus and posteriorly located mitochondria, and the other one is the axoneme. Spermatogenesis of P. harmeri is an interesting example of gamete differentiation where advanced sperm structure is combined with a plesiomorphic pattern of sperm development characterized as 'flagellate spermatogenesis'.

  7. Using of ants and earthworm to modify of soil biological quality and its effect on cocoa seedlings growth

    Science.gov (United States)

    Kilowasid, Laode Muhammad Harjoni; Budianto, Wayan; Syaf, Hasbullah; Tufaila, Muhammad; Safuan, La Ode

    2015-09-01

    Ant and earthworm can act as soil ecosystem engineers. Ant and earthworm are very dominant in smallholder cocoa plantation. The first experiment aimed to study the effect of the abundance of ants and earthworms on soil microbial activity and microfauna, and the second experiment to analyse the effect of soil modified by ants and earthworms on the cocoa seedlings growth. Ant (Ponera sp.) and earthworm (Pontoscolex sp.) collected from smallholder cocoa plantation, and kept in a container up to applied. In the first experiment, nine combinations of the abundance of ants and earthworms applied to each pot containing 3 kg of soil from smallholder cocoa plantation, and each combination of the abundance was repeated five times in a completely randomized design. After the soil was incubated for thirty days, ants and earthworms removed from the soil using hand sorting techniques. Soil from each pot was analysed for soil microbial activity, abundance of flagellates and nematodes. In the second experiment, the soil in each pot was planted with cocoa seedlings and maintained up to ninety days. The results showed the FDA hydrolytic activity of microbes, the abundance of flagellates and nematodes between the combination of the abundance of ants and earthworms have been significantly different. Dry weight of root, shoot and seedling cacao have been significantly different between the combination of the abundance of ants and earthworms. It was concluded that the combination of the abundance of ants and earthworms can be used in ecological engineering to improve soil quality.

  8. Between a Pod and a Hard Test: The Deep Evolution of Amoebae.

    Science.gov (United States)

    Kang, Seungho; Tice, Alexander K; Spiegel, Frederick W; Silberman, Jeffrey D; Pánek, Tomáš; Cepicka, Ivan; Kostka, Martin; Kosakyan, Anush; Alcântara, Daniel M C; Roger, Andrew J; Shadwick, Lora L; Smirnov, Alexey; Kudryavtsev, Alexander; Lahr, Daniel J G; Brown, Matthew W

    2017-09-01

    Amoebozoa is the eukaryotic supergroup sister to Obazoa, the lineage that contains the animals and Fungi, as well as their protistan relatives, and the breviate and apusomonad flagellates. Amoebozoa is extraordinarily diverse, encompassing important model organisms and significant pathogens. Although amoebozoans are integral to global nutrient cycles and present in nearly all environments, they remain vastly understudied. We present a robust phylogeny of Amoebozoa based on broad representative set of taxa in a phylogenomic framework (325 genes). By sampling 61 taxa using culture-based and single-cell transcriptomics, our analyses show two major clades of Amoebozoa, Discosea, and Tevosa. This phylogeny refutes previous studies in major respects. Our results support the hypothesis that the last common ancestor of Amoebozoa was sexual and flagellated, it also may have had the ability to disperse propagules from a sporocarp-type fruiting body. Overall, the main macroevolutionary patterns in Amoebozoa appear to result from the parallel losses of homologous characters of a multiphase life cycle that included flagella, sex, and sporocarps rather than independent acquisition of convergent features. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  9. Biomanufacturing and self-propulsion dynamics of nanoscale bacteria-enabled autonomous delivery systems

    Energy Technology Data Exchange (ETDEWEB)

    Traore, Mahama A.; Behkam, Bahareh, E-mail: behkam@vt.edu [Mechanical Engineering Department, Virginia Tech, Blacksburg, Virginia 24061 (United States); School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, Virginia 24061 (United States); Damico, Carmen M. [Mechanical Engineering Department, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2014-10-27

    Flagellated bacteria have superb self-propulsion capabilities and are able to effectively move through highly viscous fluid and semi-solid (porous) environments. This innate aptitude has been harvested for whole-cell actuation of bio-hybrid microrobotic systems with applications in directed transport and microassembly. In this work, we present the biomanufacturing of Nanoscale Bacteria-Enabled Autonomous Delivery Systems (NanoBEADS) by controlled self-assembly and investigate the role of nanoparticle load on the dynamics of their self-propulsion in aqueous environments. Each NanoBEADS agent is comprised of spherical polystyrene nanoparticles assembled onto the body of a flagellated Escherichia coli bacterium. We demonstrate that the NanoBEADS assembly configuration is strongly dependent upon the nanoparticles to bacteria ratio. Furthermore, we characterized the stochastic motion of the NanoBEADS as a function of the quantity and size of the nanoparticle load and computationally analyzed the effect of the nanoparticle load on the experienced drag force. We report that the average NanoBEADS swimming speed is reduced to 65% of the free-swimming bacteria speed (31 μm/s) at the highest possible load. NanoBEADS can be utilized as single agents or in a collaborative swarm in order to carry out specific tasks in a wide range of applications ranging from drug delivery to whole cell biosensing.

  10. pH-Taxis of Biohybrid Microsystems

    Science.gov (United States)

    Zhuang, Jiang; Wright Carlsen, Rika; Sitti, Metin

    2015-06-01

    The last decade has seen an increasing number of studies developing bacteria and other cell-integrated biohybrid microsystems. However, the highly stochastic motion of these microsystems severely limits their potential use. Here, we present a method that exploits the pH sensing of flagellated bacteria to realize robust drift control of multi-bacteria propelled microrobots. Under three specifically configured pH gradients, we demonstrate that the microrobots exhibit both unidirectional and bidirectional pH-tactic behaviors, which are also observed in free-swimming bacteria. From trajectory analysis, we find that the swimming direction and speed biases are two major factors that contribute to their tactic drift motion. The motion analysis of microrobots also sheds light on the propulsion dynamics of the flagellated bacteria as bioactuators. It is expected that similar driving mechanisms are shared among pH-taxis, chemotaxis, and thermotaxis. By identifying the mechanism that drives the tactic behavior of bacteria-propelled microsystems, this study opens up an avenue towards improving the control of biohybrid microsystems. Furthermore, assuming that it is possible to tune the preferred pH of bioactuators by genetic engineering, these biohybrid microsystems could potentially be applied to sense the pH gradient induced by cancerous cells in stagnant fluids inside human body and realize targeted drug delivery.

  11. Models of Plankton Community Changes during a Warm Water Anomaly in Arctic Waters Show Altered Trophic Pathways with Minimal Changes in Carbon Export

    Directory of Open Access Journals (Sweden)

    Maria Vernet

    2017-05-01

    Full Text Available Carbon flow through pelagic food webs is an expression of the composition, biomass and activity of phytoplankton as primary producers. In the near future, severe environmental changes in the Arctic Ocean are expected to lead to modifications of phytoplankton communities. Here, we used a combination of linear inverse modeling and ecological network analysis to study changes in food webs before, during, and after an anomalous warm water event in the eastern Fram Strait of the West Spitsbergen Current (WSC that resulted in a shift from diatoms to flagellates during the summer (June–July. The model predicts substantial differences in the pathways of carbon flow in diatom- vs. Phaeocystis/nanoflagellate-dominated phytoplankton communities, but relatively small differences in carbon export. The model suggests a change in the zooplankton community and activity through increasing microzooplankton abundance and the switching of meso- and macrozooplankton feeding from strict herbivory to omnivory, detritivory and coprophagy. When small cells and flagellates dominated, the phytoplankton carbon pathway through the food web was longer and the microbial loop more active. Furthermore, one step was added in the flow from phytoplankton to mesozooplankton, and phytoplankton carbon to higher trophic levels is available via detritus or microzooplankton. Model results highlight how specific changes in phytoplankton community composition, as expected in a climate change scenario, do not necessarily lead to a reduction in carbon export.

  12. Composition, diversity and distribution of microbenthos across the intertidal zones of Ryazhkov Island (the White Sea).

    Science.gov (United States)

    Azovsky, Andrey; Saburova, Maria; Tikhonenkov, Denis; Khazanova, Ksenya; Esaulov, Anton; Mazei, Yuri

    2013-11-01

    The composition and distribution of the main unicellular eukaryotic groups (diatom algae, ciliates, dinoflagellates (DF), other phototrophic (PF) and heterotrophic flagellates (HF)) were investigated in sandy sediments at five stations allocated across the tidal sheltered beach of the White Sea. Overall, 75 diatoms, 98 ciliates, 16 DF, 3 PF and 34 HF species were identified; some are new records for the White Sea. Common species for each group are illustrated. Diatoms and ciliates showed high alpha-diversity (species richness per sample), whereas flagellates were characterized by high beta-diversity (species turnover across the intertidal flat). Each group demonstrated its own spatial pattern that was best matched with its own subset of abiotic variables, reflecting group-specific responses to environmental gradients. Species richness increased from the upper intertidal zone seaward for ciliates but decreased for HF, whereas autotrophs showed a relatively uniform pattern with a slight peak at the mid-intertidal zone. Across the littoral zone, all groups showed distinct compositional changes; however, the position of the boundary between "upper" and "lower" intertidal communities varied among groups. Most of the species found at Ryazhkov Island are known from many other regions worldwide, indicating a wide geographic distribution of microbial eukaryotic species. Copyright © 2013 Elsevier GmbH. All rights reserved.

  13. Peridomiciliary colonies of Triatoma vitticeps (Stal, 1859 (Hemiptera, Reduviidae, Triatominae infected with Trypanosoma cruzi in rural areas of the state of Espírito Santo, Brazil

    Directory of Open Access Journals (Sweden)

    Claudiney Biral dos Santos

    2005-08-01

    Full Text Available In Brazil, the colonization of human dwellings by triatomines occurs in areas with native vegetation of the caatinga or cerrado types. In areas of Atlantic forest such as in the Brazilian state of Espírito Santo, there are no species adapted to live in human habitations. The few autochthonous cases of Chagas disease encountered in Espírito Santo have been attributed to adult specimens of Triatoma vitticeps that invade houses from forest remnants. In recent years, the entomology unit of the Espírito Santo State Health Secretariat has recorded nymphs infected with flagellates similar to Trypanosoma cruzi in rural localities. Entomological surveys were carried out in the residences and outbuildings in which the insects were found, and serological examinations for Chagas disease performed on the inhabitants. Four colonies were found, all associated with nests of opossums (Didelphis aurita, 111 specimens of T. vitticeps, and 159 eggs being collected. All the triatomines presented flagellates in their frass. Mice inoculated with the faeces presented trypomastigotes in the circulating blood and groups of amastigotes in the cardiac muscle fibres. Serological tests performed on the inhabitants were negative for T. cruzi. Even with the intense devastation of the forest in Espírito Santo, there are no indications of change in the sylvatic habits of T. vitticeps. Colonies of this insect associated with opossum nests would indicate an expansion of the sylvatic environment into the peridomicile.

  14. Snow as a habitat for microorganisms

    Science.gov (United States)

    Hoham, Ronald W.

    1989-01-01

    There are three major habitats involving ice and snow, and the microorganisms studied from these habitats are most eukaryotic. Sea ice is inhabited by algae called diatoms, glacial ice has sparse populations of green algai cal desmids, and the temporary and permanent snows in mountainous regions and high latitudes are inhabited mostly by green algal flagellates. The life cycle of green algal flagellates is summarized by discussing the effects of light, temperature, nutrients, and snow melts. Specific examples of optimal conditions and environmental effects for various snow algae are given. It is not likely that the eukaryotic snow algae presented are candidated for life on the planet Mars. Evolutionally, eukaryotic cells as know on Earth may not have had the opportunity to develop on Mars (if life evolved at all on Mars) since eukaryotes did not appear on Earth until almost two billion years after the first prokaryotic organisms. However, the snow/ice ecosystems on Earth present themselves as extreme habitats were there is evidence of prokaryotic life (eubacteria and cyanbacteria) of which literally nothing is known. Any future surveillances of extant and/or extinct life on Mars should include probes (if not landing sites) to investigate sites of concentrations of ice water. The possibility of signs of life in Martian polar regions should not be overlooked.

  15. Morphological characteristics of developmental stages of Acanthamoeba and Naegleria species before and after staining by various techniques.

    Science.gov (United States)

    Ithoi, Init; Ahmad, Arine-Fadzlun; Mak, J W; Nissapatorn, Veeranoot; Lau, Yee-Ling; Mahmud, Rohela

    2011-11-01

    Seven stains were studied to determine the best color and contrast for staining the developmental stages of free living pathogenic Acanthamoeba and Naegleria species. The acid-fast bacilli stain (AFB) produced a blue color without contrast; trichrome-eosin and modified Field's showed various color contrasts; Giemsa, iron-hematoxylin, modified AFB and Gram produced only one color which distinguished the nucleus, nucleolus, cytoplasm, food- and water-vacuoles. The motile organs (acanthopodia, pseudopodia, lobopodia and flagella) were also clearly differentiated but produced a similar color as the cytoplasm. These motile organelles were first induced by incubating at 37 degrees C for at least 15 minutes and then fixing with methanol in order to preserve the protruding morphology prior to staining. The trichrome-eosin and iron-hematoxylin stains showed good color contrast for detecting all three stages, the trophozoite, cyst and flagellate; Giemsa and Gram stained the trophozoite and flagellate stages; the modified Field's and modified AFB stains stained only the trophozoite stage. Depending on the purpose, all these stains (except the AFB stain) can be used to identify the developmental stages of Acanthamoeba and Naegleria for clinical, epidemiological or public health use.

  16. Estudo Comparativo das Sensilas Antenais de Operárias de Melipona scutellaris Latreille (Hymenoptera: Apidae de Diferentes Altitudes

    Directory of Open Access Journals (Sweden)

    Marcília Aparecida Nascimento

    2013-04-01

    Full Text Available Sensilas são estruturas sensoriais presentes nas antenas dos insetos e são responsáveis pela higro- quimio-, termo- e mecanorrecepção. No presente trabalho, as sensilas presentes nos três flagelômeros (F mais distais de Melipona scutellaris Latreille (Hymenopera: Apidae coletadas em diferentes altitudes (200 e acima de 900m foram avaliadas qualitativamente e quantitativamente. A identificação, contagem e medição das sensilas foram feitas a partir de imagens da superfície dorsal das antenas que foram obtidas com o auxílio de microscópio eletrônico de varredura. Foram observadas as sensilas placoide, basicônica, celocônica, ampulácea, campaniforme e tricoide reta e curvada. Comparativamente, o grupo localizado a 200m de altitude possui sensilas tricoides retas em maior quantidade nos três flagelômeros, enquanto que o grupo de altitudes acima de 900m apresentou maior quantidade de sensilas tricoides curvadas no F9, sendo as mesmas maiores para o F10. Essas diferenças foram discutidas em função da localização geográfica dos diferentes grupos aqui estudados. Os resultados da investigação da estrutura antenal de M. scutellaris contribuem para um melhor entendimento da biologia dessa espécie.

  17. ECOLOGY AND PARASITOLOGICAL ANALYSIS OF HORSE FLIES (DIPTERA: TABANIDAE IN ANTIOQUIA, COLOMBIA

    Directory of Open Access Journals (Sweden)

    PARRA-HENAO GABRIEL

    2008-07-01

    Full Text Available During the months of June to September 2006, collections of tabanids (Diptera:Tabanidae and ticks were conducted in the Caucasia municipality, Antioquia,Colombia. Tabanids were caught on horses during daylight using hand nets and pots atthe ecotone zone between secondary forests and paddock habitats. Ticks were collecteddirectly from cattle by hand. The purpose of the study was to identify possible vectorsof bovine trypanosomosis, and register the diversity and abundance of tabanids inthe zone. The arthropods were brought to the laboratory for taxonomic determinationand protozooans searching in proboscis, midgut, and salivary glands of flies. Inthe case of ticks, protozoans were searched in hemolymph. One hundred and fortytabanids belonging to four genera and nine species were caught. Among the species,Lepiselaga crassipes was the most abundant (43.6%, with the highest abundancein July and a biting peak at 14:00 h. The highest diversity of tabanids was observedduring September. Three tabanids were found infected with flagellates morphologicallycompatible with Trypanosoma vivax. 315 ticks belonging to Boophilus microplusspecies were collected, all of them negative to flagellates. These results suggest T.vivax transmission by tabanids in the study area. However, the specific status ofthe parasites should be determined by molecular techniques and the transmissionmechanism should be established too by controlled studies

  18. The evolutionary transition from subsocial to eusocial behaviour in Dictyoptera: phylogenetic evidence for modification of the "shift-in-dependent-care" hypothesis with a new subsocial cockroach.

    Science.gov (United States)

    Pellens, Roseli; D'Haese, Cyrille A; Bellés, Xavier; Piulachs, Maria-Dolors; Legendre, Frédéric; Wheeler, Ward C; Grandcolas, Philippe

    2007-05-01

    Cockroaches have always been used to understand the first steps of social evolution in termites because they are close relatives with less complex and integrated social behaviour. Termites are all eusocial and ingroup comparative analysis would be useless to infer the origin of their social behaviour. The cockroach genus Cryptocercus was used as a so-called "prototermite" model because it shows key-attributes similar to the termites (except Termitidae): wood-feeding, intestinal flagellates and subsocial behaviour. In spite of these comparisons between this subsocial cockroach and eusocial termites, the early and remote origin of eusocial behaviour in termites is not well understood yet and the study of other relevant "prototermite" models is however needed. A molecular phylogenetic analysis was carried out to validate a new "prototermite" model, Parasphaeria boleiriana which shows a peculiar combination of these key-attributes. It shows that these attributes of Parasphaeria boleiriana have an independent origin from those of other wood-eating cockroaches and termites. The case of P. boleiriana suggests that a short brood care was selected for with life on an ephemeral wood resource, even with the need for transmission of flagellates. These new phylogenetic insights modify evolutionary hypotheses, contradicting the assumption made with Cryptocercus model that a long brood care is necessary for cooperation between broods in the "shift-in-dependent-care" hypothesis. An ephemeral wood resource is suggested to prompt generation overlap and the evolution of cooperation, even if brood care is shortened.

  19. Attractiveness of black and white modified Shannon traps to phlebotomine sandflies (Diptera, Psychodidae in the Brazilian Amazon Basin, an area of intense transmission of American cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Brilhante Andreia Fernandes

    2017-01-01

    Full Text Available In the Amazon region the phlebotomine fauna is considered one of the most diverse in the world. The use of Shannon traps may provide information on the anthropophily of the species and improve the traps’ performance in terms of diversity and quantity of insects collected when white and black colored traps are used together. This study sought to verify the attractiveness of the traps to the phlebotomine species of the Brazilian Amazon basin using Shannon traps under these conditions. The insects were collected using two Shannon traps installed side by side, one white and the other black, in a primary forest area of the municipality of Xapuri, Acre, Brazil. Samples were collected once a month during the period August 2013 to July 2015. A sample of females was dissected to test for natural infection by flagellates. A total of 6,309 (864 males and 5,445 females specimens (36 species were collected. Psychodopygus carrerai carrerai (42%, Nyssomyia shawi (36%, and Psychodopygus davisi (13%, together represented 90% of the insects collected. Nyssomyia shawi and Psychodopygus davisi were more attracted by the white color. Specimens of Nyssomyia shawi, Nyssomyia whitmani, and Psychodopygus hirsutus hirsutus were found naturally infected by flagellates in the mid and hindgut. This is the first study in Acre state using and comparing both black and white Shannon traps, demonstrating the richness, diversity, and anthropophilic behavior of the phlebotomine species and identifying proven and putative vectors of the etiological agents of leishmaniasis.

  20. Impact and control of protozoan parasites in maricultured fishes.

    Science.gov (United States)

    Buchmann, Kurt

    2015-01-01

    Aquaculture, including both freshwater and marine production, has on a world scale exhibited one of the highest growth rates within animal protein production during recent decades and is expected to expand further at the same rate within the next 10 years. Control of diseases is one of the most prominent challenges if this production goal is to be reached. Apart from viral, bacterial, fungal and metazoan infections it has been documented that protozoan parasites affect health and welfare and thereby production of fish in marine aquaculture. Representatives within the main protozoan groups such as amoebae, dinoflagellates, kinetoplastid flagellates, diplomonadid flagellates, apicomplexans, microsporidians and ciliates have been shown to cause severe morbidity and mortality among farmed fish. Well studied examples are Neoparamoeba perurans, Amyloodinium ocellatum, Spironucleus salmonicida, Ichthyobodo necator, Cryptobia salmositica, Loma salmonae, Cryptocaryon irritans, Miamiensis avidus and Trichodina jadranica. The present report provides details on the parasites' biology and impact on productivity and evaluates tools for diagnosis, control and management. Special emphasis is placed on antiprotozoan immune responses in fish and a strategy for development of vaccines is presented.

  1. Control of cell division and the spatial localization of assembled gene products in Caulobacter crescentus

    International Nuclear Information System (INIS)

    Nathan, P.D.

    1988-01-01

    Experiments are described that examine the role of penicillin-binding proteins (PBPs) in the regulation of cell division in Caulobacter crescentus; and the spatial localization of methyl-accepting chemotaxis proteins (MCPs) in C. crescentus swarmer and predivisional cells. In the analysis of PBP function, in vivo and in vitro assays are used to directly label C. crescentus PBPs with [ 3 H] penicillin G in wild type strain CB15, in a series of conditional cell division mutants and in new temperature sensitive cephalosporin C resistant mutants PC8002 and PC8003. 14 PBPs are characterized and a high molecular weight PBP (PBP 1B) that is required for cell division is identified. PBP 1B competes for β-lactams that induce filament formation and may be a high affinity binding protein. A second high molecular weight PBP (PBP 1C) is also associated with defective cell division. The examination of PBP patterns in synchronous swarmer cells reveals that the in vivo activity of PBP 1B and PBP 1C increases at the time that the cell division pathway is initiated. None of the PBPs, however, appear to be differentially localized in the C. crescentus cell. In the analysis of MCP localization, in vivo and in vitro assays are used to directly label C. crescentus MCPs with methyl- 3 H. MCPs are examined in flagellated and non-flagellated vesicles prepared from cells by immunoaffinity chromatography

  2. Bacteria exploit a polymorphic instability of the flagellar filament to escape from traps.

    Science.gov (United States)

    Kühn, Marco J; Schmidt, Felix K; Eckhardt, Bruno; Thormann, Kai M

    2017-06-13

    Many bacterial species swim by rotating single polar helical flagella. Depending on the direction of rotation, they can swim forward or backward and change directions to move along chemical gradients but also to navigate their obstructed natural environment in soils, sediments, or mucus. When they get stuck, they naturally try to back out, but they can also resort to a radically different flagellar mode, which we discovered here. Using high-speed microscopy, we monitored the swimming behavior of the monopolarly flagellated species Shewanella putrefaciens with fluorescently labeled flagellar filaments at an agarose-glass interface. We show that, when a cell gets stuck, the polar flagellar filament executes a polymorphic change into a spiral-like form that wraps around the cell body in a spiral-like fashion and enables the cell to escape by a screw-like backward motion. Microscopy and modeling suggest that this propagation mode is triggered by an instability of the flagellum under reversal of the rotation and the applied torque. The switch is reversible and bacteria that have escaped the trap can return to their normal swimming mode by another reversal of motor direction. The screw-type flagellar arrangement enables a unique mode of propagation and, given the large number of polarly flagellated bacteria, we expect it to be a common and widespread escape or motility mode in complex and structured environments.

  3. Validation of a modified fluorimetric assay for the screening of trichomonacidal drugs

    Directory of Open Access Journals (Sweden)

    Alexandra Ibáñez Escribano

    2012-08-01

    Full Text Available A fluorimetric microassay that uses a redox dye to determine the viability of the flagellate Trichomonas vaginalis has been optimised to provide a more sensitive method to evaluate potential trichomonacidal compounds. Resazurin has been used in recent years to test drugs against different parasites, including trichomonadid protozoa; however, the reproducibility of these resazurin-based methods in our laboratory has been limited because the flagellate culture medium spontaneously reduces the resazurin. The objective of this work was to refine the fluorimetric microassay method previously developed by other research groups to reduce the fluorescence background generated by the media and increase the sensitivity of the screening assay. The experimental conditions, time of incubation, resazurin concentration and media used in the microtitre plates were adjusted. Different drug sensitivity studies against T. vaginalis were developed using the 5-nitroimidazole reference drugs, new 5-nitroindazolinones and 5-nitroindazole synthetic derivatives. Haemocytometer count results were compared with the resazurin assay using a 10% solution of 3 mM resazurin dissolved in phosphate buffered saline with glucose (1 mg/mL. The fluorimetric assay and the haemocytometer counts resulted in similar percentages of trichomonacidal activity in all the experiments, demonstrating that the fluorimetric microtitre assay has the necessary accuracy for high-throughput screening of new drugs against T. vaginalis.

  4. Engineering of Soil Biological Quality from Nickel Mining Stockpile Using Two Earthworm Ecological Groups

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    L M H Kilowasid

    2015-04-01

    Full Text Available Earthworms have the ability in modifying soil biological quality for plant growth. Their ability is mostly depending on its ecological groups. The objectives of the research were to study the influence of two ecological groups of earthworms on soil microbial activity and soil micro-fauna abundance, and to know the potential of soil modified by earthworms as plant growth medium. Eight combination of individual earthworm from epigeic and endogeic groups was applied into pot that was filled by soil from two years of nickel stockpile and each treatment was repeated by five times. The experiment was following complete randomize design procedure. After sixteen days of research, the soil sample from each pot was analyzed for soil FDA activity, number of flagellate and nematodes. Furthermore, one kg of the soil from each pot was taken and every pot was grown by Paraserianthes falcataria seedling with the age of five days and continued its growth for two months. The results indicated that the soil FDA activity, number of flagellate and nematodes among treatments were significantly differences. In addition, it indicated the significant differences in dry weight of shoot, root, total plant, and root to shoot ratio of P. falcataria seedlings. It concluded that the combination of an individual number of epigeic and endogeic earthworms improved soil biological quality of stock pile, amd most suitable for seedlings growth in nickel mining area.

  5. Isolation, in vitro culture, ultrastructure study, and characterization by lectin-agglutination tests of Phytomonas isolated from tomatoes (Lycopersicon esculentum) and cherimoyas (Anona cherimolia) in southeastern Spain.

    Science.gov (United States)

    Sanchez-Moreno, M; Fernandez-Becerra, C; Mascaro, C; Rosales, M J; Dollet, M; Osuna, A

    1995-01-01

    Plants of Lycopersicon esculentum (grown in greenhouses) and Anona cherimolia cultivated in southeastern Spain were examined for the presence of trypanosomatid flagellates. Kinetoplastid protozoa were found in the fruits but not in the phloem or other plant tissues. Parasites were detected from the onset of fruiting. Isolates were detected from the onset of fruiting. Isolates were adapted to in vitro culturing in monophase media. The form and the structural organization was studied by scanning and transmission electron microscopy. The parasites showed an ultrastructural pattern similar to that of other species of the genus Phytomonas. In tomatoes experimentally inoculated with flagellates cultivated in vitro, we observed that the parasites did not lose their infectious capacity. Three strains of trypanosomatids of the genus Phytomonas, isolated from different species of Euphorbia (E. characias and E. hyssopifolia) and from Cocos nucifera, were compared with our isolates by lectin-agglutination tests. Our isolates were different from the two strains isolated from Euphorbia, but with this technique we could not differentiate our isolates from those of the coconut, nor could we differentiate between the isolates, their ultrastructural similarity together with their similar behavior in the lectin-agglutination test suggesting that these isolates have a common origin.

  6. Unravelling the differences: comparative proteomic analysis of a clonal virulent and an attenuated Histomonas meleagridis strain.

    Science.gov (United States)

    Monoyios, Andreas; Patzl, Martina; Schlosser, Sarah; Hess, Michael; Bilic, Ivana

    2018-02-01

    The current study focused on Histomonas meleagridis, a unicellular protozoan, responsible for histomonosis in poultry. Recently, the occurrence of the disease increased due to the ban of effective chemotherapeutic drugs. Basic questions regarding the molecular biology, virulence mechanisms or even life cycle of the flagellate are still puzzling. In order to address some of these issues, we conducted a comparative proteomic analysis of a virulent and an attenuated H. meleagridis strain traced back to a single cell and propagated in vitro as monoxenic mono-eukaryotic cultures. Using two-dimensional electrophoresis (2-DE) for proteome visualization with computational 2-DE gel image and statistical analysis, upregulated proteins in either of the two H. meleagridis strains were detected. Statistical analysis fulfilling two criteria (≥threefold upregulation and P singled out 32 spots as specific for the flagellate. These spots were shown to correspond to 24 different proteins that reflect the increased metabolism, in vitro adaptation of the parasite, and amoeboid morphology. In addition to H. meleagridis proteins, the analysis identified differential expression of Escherichia coli DH5α proteins that could have been influenced by the co-cultivated H. meleagridis strain, indicating a reciprocal interaction of these two organisms during monoxenic cultivation. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  7. Removal of bacteria from boar ejaculates by Single Layer Centrifugation can reduce the use of antibiotics in semen extenders.

    Science.gov (United States)

    Morrell, J M; Wallgren, M

    2011-01-01

    There is considerable interest world-wide in reducing the use of antibiotics to stem the development of antibiotic-resistant strains of bacteria. An alternative to the routine addition of antibiotics to semen extenders in livestock breeding would be to separate the spermatozoa from bacterial contaminants in the semen immediately after collection. The present study was designed to determine whether such separation was possible by Single Layer Centrifugation (SLC) using the colloid Androcoll™-P. The results showed that complete removal (6 out of 10 samples), or considerable reduction of bacterial contaminants (4 out of 10 samples) was possible with this method. The type of bacteria and/or the length of time between collection and SLC-processing affected the removal of bacteria, with motile flagellated bacteria being more likely to be present after SLC than non-flagellated bacteria. Although further studies are necessary, these preliminary results suggest that the use of SLC when processing boar semen for AI doses might enable antibiotic usage in semen extenders to be reduced. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Combined effects of nitrogen content in media and Ochromonas sp. grazing on colony formation of cultured Microcystis aeruginosa

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    Zhou YANG

    2010-08-01

    Full Text Available To gain insight into the combined effects of nitrogen content in media and flagellate grazing on colony formation of Microcystis aeruginosa, we added Ochromonas sp. to M. aeruginosa cultured in different nitrogen content media for 7 days. Results showed that M. aeruginosa could be efficiently ingested by Ochromonas sp., no matter what nitrogen content media M. aeruginosa was cultured in. Colony formation was observed in M. aeruginosa in all Ochromonas sp. grazing treatments during the experiment. In contrast, M. aeruginosa populations in the controls were strongly dominated by unicellular and paired cell forms, and no colonies were observed. Among all Ochromonas sp. grazing treatments, the mean numbers of cells per particle of M. aeruginosa increased with decreased nitrogen concentration (except 0% N, therefore colony formation of M. aeruginosa can be enhanced under lower nitrogen conditions. This suggests that both nitrogen content and Ochromonas sp. grazing combine to affect M. aeruginosa colony formation. Three-way ANOVA showed a statistically significant interaction between time (day 1, 3, 5, and 7, treatment (with and without Ochromonas sp. grazing and N content (0%, 10%, 25%, and 100% N on the mean numbers of cells per particle, i.e. the extent of colony formation. At the end of the experiment, the influence of nitrogen content (except 0% N on the numbers of cells per particle followed a rectangular hyperbolic response. The experiments demonstrated that there exists a combined effect of nitrogen concentration and flagellate grazing on colony formation of M. aeruginosa under laboratory conditions.

  9. Natural infection of phlebotomines (Diptera: Psychodidae) by Leishmania (Leishmania) amazonensis in an area of ecotourism in Central-Western Brazil.

    Science.gov (United States)

    Brilhante, Andreia Fernandes; Nunes, Vânia Lúcia Brandão; Kohatsu, Kleber Augusto; Galati, Eunice Aparecida Bianchi; Rocca, Maria Elizabeth Ghizzi; Ishikawa, Edna Aoba Yassui

    2015-01-01

    Bonito municipality, known as an area of ecoturism, in Mato Grosso do Sul state, Brazil, is also a focus of visceral and cutaneous leishmaniases, with cases registered in both human and canine populations. This study sought to investigate natural infection by flagellate forms of Leishmania in phlebotomines of the urban area of Bonito. Sand flies were collected fortnightly from October 2005 to July 2006 with modified automatic light traps installed in peridomiciles and animal shelters in the center and on the outskirts of the city. The females were dissected and their guts observed under an optical microscope. A total of 1977 specimens were captured, Lutzomyia longipalpis (88.4 %) and Bichromomyia flaviscutelata (3.0 %) being the most frequent species. Bi. flaviscutellata was found infected by flagellates that were identified as Leishmania (Leishmania) amazonensis by indirect immunofluorescence reaction, employing monoclonal antibodies and the biotin-avidin system. This is the first report of natural infection by L. amazonensis in Bi. flaviscutellata in a Brazilian urban area. As Bi. flaviscutellata is only slightly attracted by humans, the transmission of L. amazonensis in the study area may have a zoonotic character; however, the sympatric occurrence of this parasite and Lu. longipalpis should be taken into consideration by the local health authorities since this sand fly has already been found with L. amazonensis DNA in a focus of canine visceral leishmaniasis in Bonito municipality.

  10. Leishmania amazonensis DNA in wild females of Lutzomyia cruzi (Diptera: Psychodidae) in the state of Mato Grosso do Sul, Brazil.

    Science.gov (United States)

    Oliveira, Everton Falcão de; Casaril, Aline Etelvina; Mateus, Nathália Lopes Fontoura; Murat, Paula Guerra; Fernandes, Wagner Souza; Oshiro, Elisa Teruya; Oliveira, Alessandra Gutierrez de; Galati, Eunice Aparecida Bianchi

    2015-12-01

    Studies on natural infection by Leishmania spp of sandflies collected in endemic and nonendemic areas can provide important information on the distribution and intensity of the transmission of these parasites. This study sought to investigate the natural infection by Leishmaniain wild female sandflies. The specimens were caught in the city of Corumbá, state of Mato Grosso do Sul (Brazil) between October 2012-March 2014, and dissected to investigate flagellates and/or submitted to molecular analysis to detect Leishmania DNA. A total of 1,164 females (77.56% of which were Lutzomyia cruzi) representing 11 species were investigated using molecular analysis; 126 specimens of Lu. cruziwere dissected and also submitted to molecular analysis. The infection rate based on the presence of Leishmania DNA considering all the sandfly species analysed was 0.69%; only Leishmania (Leishmania) amazonensis was identified in Lu. cruzi by the molecular analysis. The dissections were negative for flagellates. This is the first record of the presence of L. (L.) amazonensis DNA in Lu. cruzi, and the first record of this parasite in this area. These findings point to the need for further investigation into the possible role of this sandfly as vector of this parasite.

  11. Spatial patterns in abundance, taxonomic composition and carbon biomass of nano- and microphytoplankton in Subarctic and Arctic Seas

    Science.gov (United States)

    Crawford, David W.; Cefarelli, Adrián O.; Wrohan, Ian A.; Wyatt, Shea N.; Varela, Diana E.

    2018-03-01

    In the summers of 2007 and 2008, we studied assemblages of nano- and microphytoplankton from the subsurface chlorophyll maximum (SCM) across five broad oceanographic domains in the seas surrounding northern North America. These domains are the eastern Subarctic North Pacific (ESNP), Bering and Chukchi Seas (BE-CH), Beaufort Sea and Canada Basin (BS-CB), Canadian Arctic Archipelago (CAA), and Baffin Bay and Labrador Sea (BB-LS). Average abundance and total carbon biomass (C) of phytoplankton (>2 μm) varied ∼10-fold and ∼20-fold, respectively, across the five domains. In the BE-CH, CAA and BB-LS, diatoms averaged 35-70% and dinoflagellates 11-45% of total phytoplankton C (>2 μm), whereas in the ESNP and BS-CB, unidentified flagellates/coccoids (2-8 μm) represented a greater proportion of total C (27% and 39% respectively) than in the other domains. In the BE-CH and BB-LS, phytoplankton C (>2 μm) was dominated by dinoflagellates of the genus Gymnodinium, centric diatoms including Thalassiosira spp. and Chaetoceros spp., unidentified flagellates/coccoids (2-8 μm), and cryptomonads. In contrast, diatoms such as Thalassiosira spp. and its resting spores dominated C in the CAA, with dinoflagellates being less significant than in the BE-CH and BB-LS. Unidentified flagellates/coccoids (2-8 μm), Gymnodinium spp., and cryptomonads dominated in the ESNP, and particularly in the BS-CB, where diatoms contributed only 18% of the very low levels of total phytoplankton C (>2 μm). Phytoplankton C (>2 μm) to chlorophyll a ratios (phyto C:chl a) averaged only 31 g C g chl a-1 in the oligotrophic BS-CB domain, and 51-150 g C g chl a-1 in the other domains, whereas ratios of biogenic silica to phytoplankton C (>2 μm) (bSi:phyto C) were lowest in the eastern domains. Estimates of phytoplankton C were highly sensitive to the choice of C to cell volume equations (C:vol) adopted in the calculations, particularly in diatom-rich areas. This study highlights how diatoms and

  12. A numerical analysis of carbon dynamics of the Southern Ocean phytoplankton community: the roles of light and grazing in effecting both sequestration of atmospheric CO 2 and food availability to larval krill

    Science.gov (United States)

    Walsh, John J.; Dieterle, Dwight A.; Lenes, Jason

    2001-01-01

    Reduced ice extent within coastal regions of the Southern Ocean may lead to deeper surface mixed layers (SML), as prevail in offshore areas. A future decline of ice melt-induced stability of the water column may be associated with a shift in dominant food webs, from larger, sun-adapted diatoms grazed by euphausiids to smaller, shade-adapted flagellates consumed by salps. A basically one-dimensional numerical model of three dominant groups of the Antarctic phytoplankton community (diatoms, cryptophytes, and colonial prymnesiophytes) and four types of herbivore (protozoans, salps, copepods, and euphausiids) is used to explore the seasonal importance of both light limitation and grazing pressure on the amount of annual carbon sequestration and larval krill survival within contrasting oceanic and neritic waters, where respective validation data have been gathered during austral spring by the European JGOFS and RACER programs. With imposition of moderate and large grazing stresses, thought to be typical of offshore waters, we were able to replicate the European JGOFS 1992 observations of light penetration, phytoplankton biomass, primary production, pCO 2, bacterial biomass, labile DOC, ammonium, and total particle effluxes at 100 m within the deep SML of our model. The fidelity of such a large set of simulated state variables suggests that multiple limiting factors are indeed operating on different components of the oceanic phytoplankton community — selective grazing losses on the flagellates, but light limitation of diatoms. Release of protozoan grazing pressure in our model instead leads to unobserved spring blooms of cryptophytes, found only in laboratory enclosures. On an annual basis, weak sequestration of atmospheric CO 2 is simulated in a habitat typical of the Polar Front, while evasion of carbon dioxide occurs under biophysical conditions of the Antarctic Circumpolar Current. Stratification in shallow SML and the same absolute grazing demands by krill and

  13. Diagnosis of Pentatrichomonas hominis from domestic cats in Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Caroline S. dos Santos

    2015-12-01

    Full Text Available ABSTRACT. dos Santos C.S., McIntosh D., Berto B.P., de Jesus V.L.T., da Rocha C.N.C., Fernandes J.I., Scott F.B. & Lopes C.W.G. Diagnosis of Pentatrichomonas hominis from domestic cats in Southeastern Brazil. [Diagnóstico de Pentatrichomonas hominis em gatos no sudeste do Brasil.] Revista Brasileira de Medicina Veterinária, 37(Supl.1:25-31, 2015. Curso de Pós-Graduação em Ci- ências Veterinárias, Anexo 1, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR-465 Km 7, Campus Seropédica, RJ 23897-970, Brasil. E-mail: carolinespitz@yahoo.com.br The parabasalid flagellate Tritrichomonas foetus is recognized as the causative agent of large bowel diarrhea in domestic cats. A second species of parabasalid flagellate Pentatrichomonas hominis, has also been reported in association with domestic cats, albeit almost exclusively as a commensal organism. However, there is growing evidence to suggest that P. hominis may also be involved in feline gastro-intestinal disorders including diarrhea and that the incidence of infection with P. hominis may have been underestimated due to it being misidentified as T. foetus. The aim of the current study was to establish the basis for routine morphological identification of P. hominis employing light microscopy and to apply the methodology to the examination of cases of diarrhea in a laboratory population of Brazilian domestic cats (n =39. A detailed morphological description of P. hominis isolated from 11 cats with diarrhea was produced and molecular analyses were performed in support of the morphological data and to demonstrate the absence of T. foetus in infected cats. All animals with diarrhea were demonstrated to be infected solely with P. hominis. The findings of the current study provide a straight forward and validated method for the differential diagnosis of P. hominis and contribute to the on-going debate surrounding the pathogenic potential of this parabasalid flagellate.

  14. Reclassificação taxonômica de espécies do gênero Malassezia: revisão da literatura sobre as implicações clinicolaboratoriais Reclassification of Malassezia species: a review of its clinical and laboratory significance

    Directory of Open Access Journals (Sweden)

    Fábio dos Santos Schlottfeldt

    2002-07-01

    Full Text Available O gênero Malassezia compreende leveduras lipofílicas e lipodependentes que recentemente sofreram mudanças em sua classificação taxonômica, com a introdução de quatro novas espécies: M. globosa, M. obtusa, M. slooffiae e M. restricta, além das espécies M. furfur, M. pachydermatis e M. sympodialis, já descritas. Estas leveduras estão associadas a vários quadros patológicos que incluem infecções como a pitiríase versicolor ou dermatoses, como dermatite seborréica e dermatite atópica, entre outros. Estes quadros eram, até pouco tempo atrás, considerados devidos exclusivamente à espécie M. furfur. Estas mudanças na classificação taxonômica de Malassezia levaram a uma reavaliação dos procedimentos laboratoriais que eram utilizados para a identificação do agente etiológico. Entre eles podemos citar o estudo e a caracterização morfológica das espécies, sua tolerância térmica, suas necessidades nutricionais para determinados tipos de ácidos graxos, bem como a composição e as características do DNA de cada uma delas.The genus Malassezia comprises lipophylic and lipodependent yeast species that recently suffered a change in their taxonomic classification, with the description of four new species: M. globosa, M. obtusa, M. slooffiae and M. restricta besides the already described species M. furfur, M. pachydermatis and M. sympodialis. These yeasts are associated to pathologies that include tinea versicolor, seborrheic and atopic dermatitis, among others. These diseases were previously thought to be exclusively due to the species M. furfur. The taxonomical changes observed for species of Malassezia genus has led to a reassessment of the laboratory methodologies that were formerly used for the identification of the etiologic agent. Morphologic and physiologic variations for each species, termo-tolerance, their requirements for certain long-chain fatty acid sources, as well the composition and characteristics of their

  15. Exploring virulence and immunogenicity in the emerging pathogen Sporothrix brasiliensis.

    Science.gov (United States)

    Della Terra, Paula Portella; Rodrigues, Anderson Messias; Fernandes, Geisa Ferreira; Nishikaku, Angela Satie; Burger, Eva; de Camargo, Zoilo Pires

    2017-08-01

    Sporotrichosis is a polymorphic chronic infection of humans and animals classically acquired after traumatic inoculation with soil and plant material contaminated with Sporothrix spp. propagules. An alternative and successful route of transmission is bites and scratches from diseased cats, through which Sporothrix yeasts are inoculated into mammalian tissue. The development of a murine model of subcutaneous sporotrichosis mimicking the alternative route of transmission is essential to understanding disease pathogenesis and the development of novel therapeutic strategies. To explore the impact of horizontal transmission in animals (e.g., cat-cat) and zoonotic transmission on Sporothrix fitness, the left hind footpads of BALB/c mice were inoculated with 5×106 yeasts (n = 11 S. brasiliensis, n = 2 S. schenckii, or n = 1 S. globosa). Twenty days post-infection, our model reproduced both the pathophysiology and symptomology of sporotrichosis with suppurating subcutaneous nodules that progressed proximally along lymphatic channels. Across the main pathogenic members of the S. schenckii clade, S. brasiliensis was usually more virulent than S. schenckii and S. globosa. However, the virulence in S. brasiliensis was strain-dependent, and we demonstrated that highly virulent isolates disseminate from the left hind footpad to the liver, spleen, kidneys, lungs, heart, and brain of infected animals, inducing significant and chronic weight loss (losing up to 15% of their body weight). The weight loss correlated with host death between 2 and 16 weeks post-infection. Histopathological features included necrosis, suppurative inflammation, and polymorphonuclear and mononuclear inflammatory infiltrates. Immunoblot using specific antisera and homologous exoantigen investigated the humoral response. Antigenic profiles were isolate-specific, supporting the hypothesis that different Sporothrix species can elicit a heterogeneous humoral response over time, but cross reaction was observed

  16. Survey on germination and species composition of dinoflagellates from ballast tanks and recent sediments in ports on the South Coast of Finland, North-Eastern Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Pertola, Sari [Finnish Institute of Marine Research, Department of Biological Research, P.O. Box 2, FI-00561 Helsinki (Finland)]. E-mail sari.pertola@fimr.fi; Faust, Maria A. [Department of Botany, US National Herbarium, Smithsonian Institution, 4210 Silver Hill Road, Suitland, Maryland 20746 (United States); Kuosa, Harri [Tvaerminne Zoological Station, University of Helsinki, FI-10900 Hanko (Finland)

    2006-08-15

    Cyst beds in ships and ports in Finland have previously been unstudied. Therefore, sediments from ships' ballast water tanks and four Finnish ports were sampled for dinoflagellate cysts and other phytoplankton. Untreated sediments were incubated at 10 {sup o}C and 20 {sup o}C in the local 6 psu salinity for 1, 4 and 7 days, and vegetative cells were examined with light and scanning electron microscope. Sediments were inhabited by various dinoflagellates, diatoms, chlorophytes, cyanophytes and small flagellates. Germinated dinoflagellates were found in 90% of ballast tanks and in all ports. Gymnodiniales spp. and Heterocapsa rotundata formed a major proportion of the proliferating dinoflagellate cells. One species, Peridinium quinquecorne, not previously reported from the Baltic Sea, was identified with SEM. The study emphasises that ships are potential transport vehicles for dinoflagellate cysts even in the low salinity Finnish waters, and small-sized dinoflagellates should be focused upon in ballast water studies.

  17. Physiological characterization of gravitaxis in Euglena gracilis and Astasia longa studied on sounding rocket flights.

    Science.gov (United States)

    Richter, P R; Lebert, M; Tahedl, H; Hader, D P

    2001-01-01

    Euglena gracilis is a photosynthetic, unicellular flagellate found in eutrophic freshwater habitats. The organisms control their vertical position in the water column using gravi- and phototaxis. Recent experiments demonstrated that negative gravitaxis cannot be explained by passive buoyancy but by an active physiological mechanism. During space experiments, the threshold of gravitaxis was determined to be between 0.08 and 0.12 x g. A strong correlation between the applied acceleration and the intracellular cAMP and Ca2+ was observed. The results support the hypothesis, that the cell body of Euglena, which is denser than the surrounding medium exerts a pressure onto the lower membrane and activates mechanosensitive Ca2+ channels. Changes in the membrane potential and the cAMP concentration are most likely subsequent elements in a signal transduction chain, which results in reorientation strokes of the flagellum. c 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  18. Rapid centriole assembly in Naegleria reveals conserved roles for both de novo and mentored assembly.

    Science.gov (United States)

    Fritz-Laylin, Lillian K; Levy, Yaron Y; Levitan, Edward; Chen, Sean; Cande, W Zacheus; Lai, Elaine Y; Fulton, Chandler

    2016-03-01

    Centrioles are eukaryotic organelles whose number and position are critical for cilia formation and mitosis. Many cell types assemble new centrioles next to existing ones ("templated" or mentored assembly). Under certain conditions, centrioles also form without pre-existing centrioles (de novo). The synchronous differentiation of Naegleria amoebae to flagellates represents a unique opportunity to study centriole assembly, as nearly 100% of the population transitions from having no centrioles to having two within minutes. Here, we find that Naegleria forms its first centriole de novo, immediately followed by mentored assembly of the second. We also find both de novo and mentored assembly distributed among all major eukaryote lineages. We therefore propose that both modes are ancestral and have been conserved because they serve complementary roles, with de novo assembly as the default when no pre-existing centriole is available, and mentored assembly allowing precise regulation of number, timing, and location of centriole assembly. © 2016 Wiley Periodicals, Inc.

  19. Early decomposer assemblages of soil organisms in litterbags with vetch and rye roots

    DEFF Research Database (Denmark)

    Georgieva, Slavka; Christensen, Søren; Petersen, Henning

    2005-01-01

    and predatory nematodes (the intraguild predator) protozoa (the intraguild prey) and bacteria (the common prey). The much higher fungal biomass in rye than in vetch litterbags was not reflected in the biomass of the fungal feeders. Due to the generally lower intrinsic rate of increase of the fungivores, as well...... as of the omnivores and predators, in comparison with the bacterial feeders, they were not able to generate dense populations at this early stage of decomposition....... relationship to flagellated protozoa. This suggests that these nematodes controlled the protozoan biomass constituting a lower fraction of the bacterivore biomass in vetch compared to in rye. Such intraguild predator-prey relationship is therefore indicated for microbivorous organisms among bacterivorous...

  20. In vitro activity of Arbutus unedo leaf extracts against Trichomonas vaginalis trophozoites.

    Science.gov (United States)

    Ertabaklar, Hatice; Kivçak, Bijen; Mert, Tuba; Ozensoy Töz, Seray

    2009-01-01

    Trichomonas vaginalis (T. vaginalis) is a flagellated protozoan commonly causing sexually transmitted disease. T. vaginalis infections are treated with a 5-nitroimidazole derivate. However, drug resistance has been known to occur for a long time and new alternatives are under investigation. Arbutus unedo is a wild plant mainly growing in maquis and rocky places of the seaboard in Southern Europe. In our study, ethanolic, water, hexane and ethyl acetate extracts of Arbutus unedo leaves were tested in vitro against T. vaginalis trophozoites and the ethyl acetate extract of Arbutus unedo leaves was found to be effective (Growth inhibition rate (GI): 100%, at the concentration of 500 microg/ml). It may be a promising anti-trichomonacidal agent in the future and further experiments are needed.

  1. Action of sodium deoxycholate on Escherichia coli

    International Nuclear Information System (INIS)

    D'Mello, A.; Yotis, W.W.

    1987-01-01

    Sodium deoxycholate is used in a number of bacteriological media for the isolation and classification of gram-negative bacteria from food and the environment. Initial experiments to study the effect of deoxycholate on the growth parameters of Escherichia coli showed an increase in the lag time constant and generation time and a decrease in the growth rate constant total cell yield of this microorganisms. Cell fractionation studies indicated that sodium deoxycholate at levels used in bacteriological media interferes with the incorporation of [U- 14 C]glucose into the cold-trichloroacetic acid-soluble, ethanol-soluble, and trypsin-soluble cellular fractions of E. coli. Finally, sodium deoxycholate interfered with the flagellation and motility of Proteus mirabilis and E. coli. It would appear then that further improvement of the deoxycholate medium may be in order

  2. Microalgal composition and primary production in Arctic sea ice: a seasonal study from Kobbeijord (Kangerluarsunnguaq), West Greenland

    DEFF Research Database (Denmark)

    Mikkelsen, Ditte Marie; Rysgaard, Søren; Glud, Ronnie N.

    2008-01-01

    We investigated the microalgal community in sea ice and in the water column of Kobbefjord, west Greenland, through an entire sea ice season, Temporal variation in physical (photosynthetically active radiation [PAR), temperature, brine volume) and chemical (salinity, nutrient concentration......) properties confirmed that sea ice is a very dynamic habitat. Nevertheless, a viable sea ice algal comuunity was present throughout the year, with a species succession from flagellate dominance (dinoflagellates and cryptophytes) in December to February, followed by Chaetoceros simplex (a centric diatom...... (maxima of 1.8 and 2.6 mu g chl](-1) in March and May, respectively). Primary production mirrored biomass dynamic, which had 2 seasonal peaks of ca. 21 and 15 mg Cm-2 d(-1). Integrated primary production over 7 mo was 0.8 g Cm-2 in sea ice and 94.4 g C m(-2) in the water column, with the vast majority...

  3. Survey on germination and species composition of dinoflagellates from ballast tanks and recent sediments in ports on the South Coast of Finland, North-Eastern Baltic Sea

    International Nuclear Information System (INIS)

    Pertola, Sari . E-mail sari.pertola@fimr.fi; Faust, Maria A.; Kuosa, Harri

    2006-01-01

    Cyst beds in ships and ports in Finland have previously been unstudied. Therefore, sediments from ships' ballast water tanks and four Finnish ports were sampled for dinoflagellate cysts and other phytoplankton. Untreated sediments were incubated at 10 o C and 20 o C in the local 6 psu salinity for 1, 4 and 7 days, and vegetative cells were examined with light and scanning electron microscope. Sediments were inhabited by various dinoflagellates, diatoms, chlorophytes, cyanophytes and small flagellates. Germinated dinoflagellates were found in 90% of ballast tanks and in all ports. Gymnodiniales spp. and Heterocapsa rotundata formed a major proportion of the proliferating dinoflagellate cells. One species, Peridinium quinquecorne, not previously reported from the Baltic Sea, was identified with SEM. The study emphasises that ships are potential transport vehicles for dinoflagellate cysts even in the low salinity Finnish waters, and small-sized dinoflagellates should be focused upon in ballast water studies

  4. Impacts of radiation exposure on the experimental microbial ecosystem: a particle-based model simulation approach

    International Nuclear Information System (INIS)

    Doi, M.; Tanaka, N.; Fuma, S.; Kawabata, Z.

    2004-01-01

    Well-designed experimental model ecosystem could be a simple reference of the actual environment and complex ecological systems. For ecological toxicity test of radiation and other environmental toxicants, we investigated and aquatic microbial ecosystem (closed microcosm) in the test tube with initial substrates,autotroph flagellate algae (Euglena, G.), heterotroph ciliate protozoa (Tetrahymena T.) and saprotroph bacteria (E, coli). These species organizes by itself to construct the ecological system, that keeps the sustainable population dynamics for more than 2 years after inoculation only by adding light diurnally and controlling temperature at 25 degree Celsius. Objective of the study is to develop the particle-based computer simulation by reviewing interactions among microbes and environment, and analyze the ecological toxicities of radiation on the microcosm by replicating experimental results in the computer simulation. (Author) 14 refs

  5. Swimming in an anisotropic fluid: How speed depends on alignment angle

    Science.gov (United States)

    Shi, Juan; Powers, Thomas R.

    2017-12-01

    Orientational order in a fluid affects the swimming behavior of flagellated microorganisms. For example, bacteria tend to swim along the director in lyotropic nematic liquid crystals. To better understand how anisotropy affects propulsion, we study the problem of a sheet supporting small-amplitude traveling waves, also known as the Taylor swimmer, in a nematic liquid crystal. For the case of weak anchoring of the nematic director at the swimmer surface and in the limit of a minimally anisotropic model, we calculate the swimming speed as a function of the angle between the swimmer and the nematic director. The effect of the anisotropy can be to increase or decrease the swimming speed, depending on the angle of alignment. We also show that elastic torque dominates the viscous torque for small-amplitude waves and that the torque tends to align the swimmer along the local director.

  6. Oxygen respiration rates of benthic foraminifera as measured with oxygen microsensors

    DEFF Research Database (Denmark)

    Geslin, E.; Risgaard-Petersen, N.; Lombard, Fabien

    2011-01-01

    of the foraminiferal specimens. The results show a wide range of oxygen respiration rates for the different species (from 0.09 to 5.27 nl cell−1 h−1) and a clear correlation with foraminiferal biovolume showed by the power law relationship: R = 3.98 10−3 BioVol0.88 where the oxygen respiration rate (R) is expressed......Oxygen respiration rates of benthic foraminifera are still badly known, mainly because they are difficult to measure. Oxygen respiration rates of seventeen species of benthic foraminifera were measured using microelectrodes and calculated on the basis of the oxygen fluxes measured in the vicinity...... groups (nematodes, copepods, ostracods, ciliates and flagellates) suggests that benthic foraminifera have a lower oxygen respiration rates per unit biovolume. The total contribution of benthic foraminifera to the aerobic mineralisation of organic matter is estimated for the studied areas. The results...

  7. Characterization of a Novel Association between Two Trypanosome-Specific Proteins and 5S rRNA

    Science.gov (United States)

    Ciganda, Martin; Williams, Noreen

    2012-01-01

    P34 and P37 are two previously identified RNA binding proteins in the flagellate protozoan Trypanosoma brucei. RNA interference studies have determined that the proteins are essential and are involved in ribosome biogenesis. Here, we show that these proteins interact in vitro with the 5S rRNA with nearly identical binding characteristics in the absence of other cellular factors. The T. brucei 5S rRNA has a complex secondary structure and presents four accessible loops (A to D) for interactions with RNA-binding proteins. In other eukaryotes, loop C is bound by the L5 ribosomal protein and loop A mainly by TFIIIA. The binding of P34 and P37 to T. brucei 5S rRNA involves the LoopA region of the RNA, but these proteins also protect the L5 binding site located on LoopC. PMID:22253864

  8. Visceral leishmaniasis and HIV coinfection in the Mediterranean region.

    Directory of Open Access Journals (Sweden)

    Begoña Monge-Maillo

    2014-08-01

    Full Text Available Visceral leishmaniasis is hypoendemic in Mediterranean countries, where it is caused by the flagellate protozoan Leishmania infantum. VL cases in this area account for 5%-6% of the global burden. Cases of Leishmania/HIV coinfection have been reported in the Mediterranean region, mainly in France, Italy, Portugal, and Spain. Since highly active antiretroviral therapy was introduced in 1997, a marked decrease in the number of coinfected cases in this region has been reported. The development of new diagnostic methods to accurately identify level of parasitemia and the risk of relapse is one of the main challenges in improving the treatment of coinfected patients. Clinical trials in the Mediterranean region are needed to determine the most adequate therapeutic options for Leishmania/HIV patients as well as the indications and regimes for secondary prophylaxis. This article reviews the epidemiological, diagnostic, clinical, and therapeutic aspects of Leishmania/HIV coinfection in the Mediterranean region.

  9. On the General Analytical Solution of the Kinematic Cosserat Equations

    KAUST Repository

    Michels, Dominik L.

    2016-09-01

    Based on a Lie symmetry analysis, we construct a closed form solution to the kinematic part of the (partial differential) Cosserat equations describing the mechanical behavior of elastic rods. The solution depends on two arbitrary analytical vector functions and is analytical everywhere except a certain domain of the independent variables in which one of the arbitrary vector functions satisfies a simple explicitly given algebraic relation. As our main theoretical result, in addition to the construction of the solution, we proof its generality. Based on this observation, a hybrid semi-analytical solver for highly viscous two-way coupled fluid-rod problems is developed which allows for the interactive high-fidelity simulations of flagellated microswimmers as a result of a substantial reduction of the numerical stiffness.

  10. Ichthyouris voltagrandensis n.sp. (Nematoda: Pharyngodonidae) from Myleus tiete Eigenmann & Norris, 1900 (Osteichthyes: Characidae) in the Volta Grande Reservoir, MG, Brazil.

    Science.gov (United States)

    Martins, M L; Yoshitoshi, E R; Umekita, H

    2001-05-01

    The present work studied helminth parasites of "pacu-manteiga", Myleus tiete (Osteichthyes: Characidae) from Volta Grande Reservoir, MG, Brazil. Fishes with 142.6 +/- 24.7 g weight and 17.3 +/- 1.0 cm total length were collected. Five out six analysed fish (prevalence 83.3%) were parasitized in the intestine with an average of 535.6 +/- 334.6 oxyurid nematodes per fish. The helminth was identified as Ichthyouris voltagrandensis n.sp. (Nematoda: Pharyngodonidae). It differs from I. brasiliensis (Moravec et al., 1992a) by the absence of lateral alae, higher measures of tail and caudal alae of males, esophageal isthmus length, distance of excretory pore from anterior end and spicule length. In addition, eggs were provided by two long filaments in just one pole and by the first time the authors observed flagellate spermatozoa from dissected males. The authors exposes comparative table of measures of the five described species of the genus Ichthyouris.

  11. Leishmania hijacking of the macrophage intracellular compartments.

    Science.gov (United States)

    Liévin-Le Moal, Vanessa; Loiseau, Philippe M

    2016-02-01

    Leishmania spp., transmitted to humans by the bite of the sandfly vector, are responsible for the three major forms of leishmaniasis, cutaneous, diffuse mucocutaneous and visceral. Leishmania spp. interact with membrane receptors of neutrophils and macrophages. In macrophages, the parasite is internalized within a parasitophorous vacuole and engages in a particular intracellular lifestyle in which the flagellated, motile Leishmania promastigote metacyclic form differentiates into non-motile, metacyclic amastigote form. This phenomenon is induced by Leishmania-triggered events leading to the fusion of the parasitophorous vacuole with vesicular members of the host cell endocytic pathway including recycling endosomes, late endosomes and the endoplasmic reticulum. Maturation of the parasitophorous vacuole leads to the intracellular proliferation of the Leishmania amastigote forms by acquisition of host cell nutrients while escaping host defense responses. © 2015 FEBS.

  12. Amoebae and other protozoa in material samples from moisture-damaged buildings

    International Nuclear Information System (INIS)

    Yli-Pirilae, T.; Kusnetsov, Jaana; Haatainen, Susanna; Haenninen, Marja; Jalava, Pasi; Reiman, Marjut; Seuri, Markku; Hirvonen, Maija-Riitta; Nevalainen, Aino

    2004-01-01

    Mold growth in buildings has been shown to be associated with adverse health effects. The fungal and bacterial growth on moistened building materials has been studied, but little attention has been paid to the other organisms spawning in the damaged materials. We examined moist building materials for protozoa, concentrating on amoebae. Material samples (n=124) from moisture-damaged buildings were analyzed for amoebae, fungi, and bacteria. Amoebae were detected in 22% of the samples, and they were found to favor cooccurrence with bacteria and the fungi Acremonium spp., Aspergillus versicolor, Chaetomium spp., and Trichoderma spp. In addition, 11 seriously damaged samples were screened for other protozoa. Ciliates and flagellates were found in almost every sample analyzed. Amoebae are known to host pathogenic bacteria, such as chlamydiae, legionellae, and mycobacteria and they may have a role in the complex of exposure that contributes to the health effects associated with moisture damage in buildings

  13. The structure of the pelagic food web in relation to water column structure in the Skagerrak

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Kaas, H.; Kruse, B.

    1990-01-01

    by a doming of the pycnocline, with a deep mixed layer along the periphery and a very shallow pycnocline in central parts. Average phytoplankton size increased with the depth of the upper mixed layer, and the central stratified area was characterized by small flagellates while large and chain-forming diatoms...... on particle surface area rather than particle volume or chl a, and showed a distributional pattern that was nearly the inverse of the distribution of copepod activity. That is, peak bacterial growth rates occurred in central, stratified parts and lower rates were found along the margin with a deep mixed layer....... Thus a 'microbial loop' type of food web seemed to be evolving in the central, strongly stratified parts of the Skagerrak, while a shorter 'classical' type of food web appeared to dominate along the margin. The relation between food web structure and vertical mixing processes observed on oceanwide...

  14. Consideraciones sobre «Ferrando Spagnuolo» y otros maestros ibéricos

    Directory of Open Access Journals (Sweden)

    Condorelli, Adele

    1998-12-01

    Full Text Available The review of the two exhibitions on the Hernandos held at Valencia and, on a minor scale, in Florence, sheds a special light on the noteworthy contribution given by the two Spanish painters to the dissemination of the oil painting technique in Florentine circles at the end of the 15th Century; mention is made of how Yañez drew inspiration from a drawing by Pollaiolo in conceiving the scene of the Baptist's Decollation. As for the Florence exhibition, the review rejects the attribution to Yañez of a part of Pecori's Circumcision. The problem of the Master of Bolea, with regard to Atri's paintings, is raised once again with specific references to drawings of Perugino for the Nativity and of Pollaiolo for the Flagellation.No disponible

  15. Bacterial growth on macrophyte leachate and fate of bacterial production

    International Nuclear Information System (INIS)

    Findlay, S.; Carlough, L.; Crocker, M.T.; Gill, H.K.; Meyer, J.L.; Smith, P.J.

    1986-01-01

    The role bacteria play in transferring organic carbon to other trophic levels in aquatic ecosystems depends on the efficiency with which they convert dissolved organic [ 14 C]-labelled carbon into bacterial biomass and on the ability of consumers to graze bacteria. The authors have measured the conversion efficiency for bacteria growing on macrophyte-derived dissolved organic carbon and estimated the amount of bacterial production removed by grazing. Bacteria converted this DOC into new tissue with an efficiency of 53%, substantially higher than the apparent conversion efficiency of macrophyte-derived particulate organic carbon or other types of DOC. Two estimates of grazing indicate that the decline in bacterial numbers after the bloom was probably due to grazing by flagellates. These results show the significance of the bacterial link between DOC and other trophic levels

  16. Bacteria are not too small for spatial sensing of chemical gradients: An experimental evidence

    DEFF Research Database (Denmark)

    Thar, Roland; Kühl, Michael

    2003-01-01

    By analyzing the chemotactic behavior of a recently described marine bacterial species, we provide experimental evidence that bacteria are not too small for sensing chemical gradients spatially. The bipolar flagellated vibrioid bacteria (typical size 2 × 6 µm) exhibit a unique motility pattern...... as they translate along as well as rotate around their short axis, i.e., the pathways of the cell poles describe a double helix. The natural habitat of the bacteria is characterized by steep oxygen gradients where they accumulate in a band at their preferred oxygen concentration of ˜2 µM. Single cells leaving...... the band toward the oxic region typically return to the band within 16 s following a U-shaped track. A detailed analysis of the tracks reveals that the cells must be able to sense the oxygen gradient perpendicular to their swimming direction. Thus, they can detect oxygen gradients along a distance of ˜5 µm...

  17. Virus-like particles suppress growth of the red-tide-forming marine dinoflagellate Gymnodinium mikimotoi.

    Science.gov (United States)

    Onji, Masashi; Nakano, Shin-ichi; Suzuki, Satoru

    2003-01-01

    We isolated 2 virus-like agents that suppressed growth of Gymnodinium mikimotoi from coastal waters of the Uwa Sea, Japan. The agents found in the flagellate cells, named GM6 and GM7, were filterable in a 0.22-microm-pore filter with approximately 100-nm shapes. Electron microscopic observation showed the presence of virus-like particles in severely damaged G. mikimotoi cells infected by GM6. The growth-suppression activity of the agents (GM6 or GM7) was lost by heating at 50 degrees C, with treatments of DNase and protease, and filtration through a 0.05-microm filter. Our results suggest that the agents are DNA viruses infectious to and virulent for G. mikimotoi. This is the first report of a virus-like agent specific to G. mikimotoi.

  18. Microalgal composition and primary production in Arctic sea ice: a seasonal study from Kobbeijord (Kangerluarsunnguaq), West Greenland

    DEFF Research Database (Denmark)

    Mikkelsen, Ditte Marie; Rysgaard, Søren; Glud, Ronnie N.

    2008-01-01

    We investigated the microalgal community in sea ice and in the water column of Kobbefjord, west Greenland, through an entire sea ice season, Temporal variation in physical (photosynthetically active radiation [PAR), temperature, brine volume) and chemical (salinity, nutrient concentration...... (maxima of 1.8 and 2.6 mu g chl](-1) in March and May, respectively). Primary production mirrored biomass dynamic, which had 2 seasonal peaks of ca. 21 and 15 mg Cm-2 d(-1). Integrated primary production over 7 mo was 0.8 g Cm-2 in sea ice and 94.4 g C m(-2) in the water column, with the vast majority......) properties confirmed that sea ice is a very dynamic habitat. Nevertheless, a viable sea ice algal comuunity was present throughout the year, with a species succession from flagellate dominance (dinoflagellates and cryptophytes) in December to February, followed by Chaetoceros simplex (a centric diatom...

  19. Minimal infectious doses and prepatent periods in Giardia muris, Spironucleus muris and Tritrichomonas muris.

    Science.gov (United States)

    Stachan, R; Kunstýr, I

    1983-12-01

    The minimal infectious doses (MID) of Giardia muris cysts, Spironucleus muris cysts and Tritrichomonas muris pseudocysts for athymic mice were determined. A novel micromanipulator-aided technique was developed for selecting small exact numbers of specified fresh or old cysts/pseudocysts from a faecal homogenate. This technique can also be of value in manipulating protozoan parasites of any particular species. Only fresh cysts/pseudocysts, which appeared bright under phase contrast optics, were infectious. Older cysts and pseudocysts which appeared dark in phase contrast were not infectious. The MID for three murine intestinal flagellates addressed above were: 10 (between 5 and 20), 1 and 5 cysts/pseudocysts respectively. Corresponding prepatent periods (PP) were 8, 5 and 10 days. A relation was evident between the infectious dose and the PP: The prepatent period shortened with an increased infectious dose.

  20. Natural infection of the sand fly Phlebotomus kazeruni by Trypanosoma species in Pakistan

    Directory of Open Access Journals (Sweden)

    Iwata Hiroyuki

    2010-02-01

    Full Text Available Abstract The natural infection of phlebotomine sand flies by Leishmania parasites was surveyed in a desert area of Pakistan where cutaneous leishmaniasis is endemic. Out of 220 female sand flies dissected, one sand fly, Phlebotomus kazeruni, was positive for flagellates in the hindgut. Analyses of cytochrome b (cyt b, glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH and small subunit ribosomal RNA (SSU rRNA gene sequences identified the parasite as a Trypanosoma species of probably a reptile or amphibian. This is the first report of phlebotomine sand flies naturally infected with a Trypanosoma species in Pakistan. The possible infection of sand flies with Trypanosoma species should be taken into consideration in epidemiological studies of vector species in areas where leishmaniasis is endemic.

  1. Growth and differentiation on a trypanosome of the subgenus Schizotrypanum from the bat Phyllostomus hastatus

    Directory of Open Access Journals (Sweden)

    Sônia I. Hamanaka

    1993-12-01

    Full Text Available The effects of temperature, pH, osmolarity and aeration on the growth and differentiation of a trypanosome ofthe subgenus Schizotrypanum isolatedfrom the bat Phyllostomus hastatus were studied. In general, the growth characteristics ofthe flagellate were similar to those of Trypanosoma (Schizotrypanum cruzi. However, the parasite did not growth at 33 or 37C. Increase in the osmolarity and aeration promoted growth at 33C. Significant metacyclogenesis was detected only in the growth condition where maximal growth occured (28C, pH 7.3, 380m0s/kg, in tissue cullure flasks, at the end ofthe exponential growth phase. The begining of the metacyclogenesis process was coincident with most glucose utilization and lowest pH. During metacyclogenesis both culture medium pH and osmolarity increased steadly.

  2. Soil fauna communities and microbial respiration in high Arctic tundra soils at Zackenberg, Northeast Greenland

    DEFF Research Database (Denmark)

    Sørensen, Louise I.; Holmstrup, Martin; Maraldo, Kristine

    2006-01-01

    The soil fauna communities were described for three dominant vegetation types in a high arctic site at Zackenberg, Northeast Greenland. Soil samples were extracted to quantify the densities of mites, collembolans, enchytraeids, diptera larvae, nematodes and protozoa. Rates of microbial respiration...... densities (naked amoeba and heterotrophic flagellates) were equal. Respiration rate of unamended soil was similar in soil from the three plots. However, a higher respiration rate increase in carbon + nutrient amended soil and the higher densities of soil fauna (with the exception of mites and protozoa...... were also assessed. Collembolans were found in highest densities in dry heath soil, about 130,000 individuals m-2, more than twice as high as in mesic heath soils. Enchytraeids, diptera larvae and nematodes were also more abundant in the dry heath soil than in mesic heath soils, whereas protozoan...

  3. Protist community in soil: Effects of different land-use types

    DEFF Research Database (Denmark)

    Santos, Susana; Schöler, Anne; Winding, Anne

    Soil protist microorganisms represent an important part of the soil microbial community being major players in providing ecosystem services. Changes in their community structure and dynamics may influence the rate and kind of soil formation and fertility. Corroborative studies indicate that protist...... microorganisms exhibit high levels of molecular and functional diversity in soils. However, studies questioning the protist diversity in soil and their variability across different soil land-use types, have received far less attention. The purpose of our study was to obtain relative abundances of flagellate......, cilliates and amoeboid soil protists, and to relate the expected changes in community composition to space and land-use. Within the EU FP7 project EcoFINDERS, soils were collected from six long-term observatories (LTO’s) scattered around Europe, covering different climatic zones and different vegetation...

  4. Alternative cytoskeletal landscapes: cytoskeletal novelty and evolution in basal excavate protists

    Science.gov (United States)

    Dawson, Scott C.; Paredez, Alexander R.

    2016-01-01

    Microbial eukaryotes encompass the majority of eukaryotic evolutionary and cytoskeletal diversity. The cytoskeletal complexity observed in multicellular organisms appears to be an expansion of components present in genomes of diverse microbial eukaryotes such as the basal lineage of flagellates, the Excavata. Excavate protists have complex and diverse cytoskeletal architectures and life cycles – essentially alternative cytoskeletal “landscapes” – yet still possess conserved microtubule- and actin-associated proteins. Comparative genomic analyses have revealed that a subset of excavates, however, lack many canonical actin-binding proteins central to actin cytoskeleton function in other eukaryotes. Overall, excavates possess numerous uncharacterized and “hypothetical” genes, and may represent an undiscovered reservoir of novel cytoskeletal genes and cytoskeletal mechanisms. The continued development of molecular genetic tools in these complex microbial eukaryotes will undoubtedly contribute to our overall understanding of cytoskeletal diversity and evolution. PMID:23312067

  5. Aerobic mitochondria of parasitic protists: Diverse genomes and complex functions.

    Science.gov (United States)

    Zíková, Alena; Hampl, Vladimír; Paris, Zdeněk; Týč, Jiří; Lukeš, Julius

    In this review the main features of the mitochondria of aerobic parasitic protists are discussed. While the best characterized organelles are by far those of kinetoplastid flagellates and Plasmodium, we also consider amoebae Naegleria and Acanthamoeba, a ciliate Ichthyophthirius and related lineages. The simplistic view of the mitochondrion as just a power house of the cell has already been abandoned in multicellular organisms and available data indicate that this also does not apply for protists. We discuss in more details the following mitochondrial features: genomes, post-transcriptional processing, translation, biogenesis of iron-sulfur complexes, heme metabolism and the electron transport chain. Substantial differences in all these core mitochondrial features between lineages are compatible with the view that aerobic protists harbor organelles that are more complex and flexible than previously appreciated. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Nanoplankton protists from the western Mediterranean Sea. II. Cryptomonads (Cryptophyceae = Crptomonadea

    Directory of Open Access Journals (Sweden)

    Gianfranco Novarino

    2005-03-01

    Full Text Available This paper is an electron microscopical account of cryptomonad flagellates (Cryptophyceae = Cryptomonadea in the plankton of the western Mediterranean Sea. Bottle samples collected during the spring-summer of 1998 in the Sea of Alboran and Barcelona coastal waters contained a total of eleven photosynthetic species: Chroomonas (sensu auctorum sp., Cryptochloris sp., 3 species of Hemiselmis, 3 species of Plagioselmis including Plagioselmis nordica stat. nov/sp. nov., Rhinomonas reticulata (Lucas Novarino, Teleaulax acuta (Butcher Hill, and Teleaulax amphioxeia (Conrad Hill. Identification was based largely on cell surface features, as revealed by scanning electron microscopy (SEM. Cells were either dispersed in the water-column or associated with suspended particulate matter (SPM. Plagioselmis prolonga was the most common species both in the water-column and in association with SPM, suggesting that it might be a key primary producer of carbon. Taxonomic keys are given based on SEM.

  7. [Changes in Cell Surface Properties and Biofilm Formation Efficiency in Azospirillum brasilense Sp245 Mutants in the Putative Genes of Lipid Metabolism mmsB1 and fabG1].

    Science.gov (United States)

    Shumilova, E; Shelud'ko, A V; Filip'echeva, Yu A; Evstigneeva, S S; Ponomareva, E G; Petrova, L P; Katsy, E I

    2016-01-01

    The previously obtained insertion mutants ofAzospirillum brasilense Sp245 in the genes mmsBl and fabG1 (strains SK039 and Sp245.1610, respectively) were characterized by impaired flagellation and motility. The putative products of expression of these genes are 3-hydroxyisobutyrate dehydrogenase and 3-oxoacyl-[acyl-carrier protein] reductase, respectively. In the present work, A. brasilense- Sp245 strains SK039 and Sp245.1610 were found to have differences in the content of 3-hydroxyhexadecanoic, hexadecanoic, 3-hydroxytetradecanoic, hexadecenoic, octadecenoic, and nonadecanoic acids in their lipopolysaccharide prepa- rations, as well as in cell hydrophobicity and hemagglutination activity and dynamics of cell aggregation, in biomass amount, and in the relative content of lipopolysaccharide antigens in mature biofilms formed on hydrophilic or hydrophobic surfaces.

  8. [Biofilm Formation by the Nonflagellated flhB1 Mutant of Azospirillum brasilense Sp245].

    Science.gov (United States)

    Shelud'ko, A V; Filip'echeva, Yu A; Shumiliva, E M; Khlebtsov, B N; Burov, A M; Petrova, L P; Katsy, E I

    2015-01-01

    Azospirillum brasilense Sp245 with mixed flagellation are able to form biofilms on various surfaces. A nonflagellated mutant of this strain with inactivated chromosomal copy of the flhB gene (flhB1) was shown to exhibit specific traits at the later stages of biofilm formation on a hydrophilic (glass) surface. Mature biofilms of the flhB1::Omegon-Km mutant Sp245.1063 were considerably thinner than those of the parent strain Sp245. The biofilms of the mutant were more susceptible to the forces of hydrodynamic shear. A. brasilense Sp245 cells in biofilms were not found to possess lateral flagella. Cells with polar flagella were, however, revealed by atomic force microscopy of mature native biofilms of strain Sp245. Preservation of a polar flagellum (probably nonmotile) on the cells of A. brasilense Sp245 may enhance the biofilm stability.

  9. Heterotrophic utilization of acetate and glucose in Swartvlei, South Africa

    International Nuclear Information System (INIS)

    Robarts, R.D.

    1979-01-01

    The utilization of dissolved organic compounds in Swartvlei was measured by the addition of single concentrations of 14 C-labelled acetate and glucose to water samples. The results indicated acetate uptake was greatest in the aerobic zone while glucose was predominantly utilized in the anaerobic zone. With the exception of two months, integral glucose uptake was usually greater than the uptake of acetate. In August and September 1971 acetate was indicated as being utilized predominantly by flagellates and in December 1971 by dinoflagellates. During the remainder of the study, bacteria were assumed to be responsible for the uptake of acetate. The extensive weed beds which surround the upper reaches of Swartvlei may be a major source of acetate and glucose in the pelagic water column

  10. Morphologic aspects of Tetratrichomonas didelphidis isolated from opossums Didelphis marsupialis and Lutreolina crassicaudata

    Directory of Open Access Journals (Sweden)

    Tiana Tasca

    2001-02-01

    Full Text Available Tetratrichomonas didelphidis (Hegner & Ratcliffe, 1927 Andersen & Reilly, 1965 is a flagellate protozoan found in the intestine, cecum, and colon of Didelphis marsupialis. The parasitic protozoa used in this study was found and isolated in the intestine of opossums in Pavlova starch-containing medium in Florianópolis, State of Santa Catarina, Brazil, from D. marsupialis and Lutreolina crassicaudata. The strains were cultivated in Diamond medium without maltose and with starch solution, pH 7.5 at 28°C. The specimens were stained by the Giemsa method and Heidenhain's iron hematoxylin. The light microscopy study of the trophozoites revealed the same morphologic characteristics as specimens previously described.

  11. Anothor Trypanosoma, distinct from T. cruzi, multiplies in the lumen of the anal glands the opossum Didelphis marsupialis

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    Maria P. Deane

    1986-03-01

    Full Text Available Epimastigotes were found multiplying in the anal glands and in hemocultures of an opossum; rare metacyclics were seen in the cultures. The flagellate is possibly T. (Megatrypanum freitasi Rego, Magalhães & Siqueira, 1957, but its final identification is still pending.Um tripanosoma ainda não identificado foi encontrado multiplicando-se como epimastigotas extracelulares na glândulas anais de um gambá. Trata-se possivelmente do T. (M. freitasi. O achado demonstra que tal localização não se restringe ao T. cruzi e sugere que os tripanosomatídeos devem ser buscados nesta e em outras situações inortodoxas, no organismo dos hospedeiros vertebrados.

  12. Action of sodium deoxycholate on Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    D' Mello, A.; Yotis, W.W.

    1987-08-01

    Sodium deoxycholate is used in a number of bacteriological media for the isolation and classification of gram-negative bacteria from food and the environment. Initial experiments to study the effect of deoxycholate on the growth parameters of Escherichia coli showed an increase in the lag time constant and generation time and a decrease in the growth rate constant total cell yield of this microorganisms. Cell fractionation studies indicated that sodium deoxycholate at levels used in bacteriological media interferes with the incorporation of (U-/sup 14/C)glucose into the cold-trichloroacetic acid-soluble, ethanol-soluble, and trypsin-soluble cellular fractions of E. coli. Finally, sodium deoxycholate interfered with the flagellation and motility of Proteus mirabilis and E. coli. It would appear then that further improvement of the deoxycholate medium may be in order.

  13. Human sperm steer with second harmonics of the flagellar beat.

    Science.gov (United States)

    Saggiorato, Guglielmo; Alvarez, Luis; Jikeli, Jan F; Kaupp, U Benjamin; Gompper, Gerhard; Elgeti, Jens

    2017-11-10

    Sperm are propelled by bending waves traveling along their flagellum. For steering in gradients of sensory cues, sperm adjust the flagellar waveform. Symmetric and asymmetric waveforms result in straight and curved swimming paths, respectively. Two mechanisms causing spatially asymmetric waveforms have been proposed: an average flagellar curvature and buckling. We image flagella of human sperm tethered with the head to a surface. The waveform is characterized by a fundamental beat frequency and its second harmonic. The superposition of harmonics breaks the beat symmetry temporally rather than spatially. As a result, sperm rotate around the tethering point. The rotation velocity is determined by the second-harmonic amplitude and phase. Stimulation with the female sex hormone progesterone enhances the second-harmonic contribution and, thereby, modulates sperm rotation. Higher beat frequency components exist in other flagellated cells; therefore, this steering mechanism might be widespread and could inspire the design of synthetic microswimmers.

  14. On the General Analytical Solution of the Kinematic Cosserat Equations

    KAUST Repository

    Michels, Dominik L.; Lyakhov, Dmitry; Gerdt, Vladimir P.; Hossain, Zahid; Riedel-Kruse, Ingmar H.; Weber, Andreas G.

    2016-01-01

    Based on a Lie symmetry analysis, we construct a closed form solution to the kinematic part of the (partial differential) Cosserat equations describing the mechanical behavior of elastic rods. The solution depends on two arbitrary analytical vector functions and is analytical everywhere except a certain domain of the independent variables in which one of the arbitrary vector functions satisfies a simple explicitly given algebraic relation. As our main theoretical result, in addition to the construction of the solution, we proof its generality. Based on this observation, a hybrid semi-analytical solver for highly viscous two-way coupled fluid-rod problems is developed which allows for the interactive high-fidelity simulations of flagellated microswimmers as a result of a substantial reduction of the numerical stiffness.

  15. Seasonality of Lutzomyia fairtigi (Diptera: Psychodidae: Phlebotominae), a species endemic to Eastern Colombia.

    Science.gov (United States)

    Molina, Jorge Alberto; Ortiz, Mario Iván; Guhl, Felipe

    2008-08-01

    The bionomics of sand flies (Diptera: Phlebotominae) was studied monthly for two consecutive years in alluvial gallery forests in the department of Casanare, Northeastern Colombia. A total of 2,365 specimens and 10 species were captured using CDC light traps and Shannon traps, and from diurnal resting places, and human landing collections. Lutzomyia fairtigi Martins (55%), Lutzomyia micropyga (Mangabeira) (20.9%), and Lutzomyia antunesi (Coutinho) (13.5%) were the predominant species in the region. Lutzomyia flaviscutellata and Lutzomyia panamensis, potential vectors of Leishmania in Colombia and neighboring countries, were also collected, but in low numbers. Lu. fairtigi is an endemic species to Colombia, and minimal data are available on its biology and distribution. The present study provides additional information about Lu. fairtigi, such as the diurnal activity displayed by females on cloudy days, the greater density during the rainy season (April to October), marked anthropophilia, and the presence of flagellates in the midgut of one female.

  16. Motile male gametes of the araphid diatom Tabularia fasciculata search randomly for mates.

    Directory of Open Access Journals (Sweden)

    Robyn Edgar

    Full Text Available Sexuality in the marine araphid diatom Tabularia involves an unusual type of gamete, not only among diatoms but possibly in all of nature. The non-flagellated male gamete is free and vigorously motile, propelled by pseudopodia. However, the cues (if any in their search for compatible female gametes and the general search patterns to locate them are unknown. We tracked and compared male gamete movements in the presence and absence of receptive female gametes. Path linearity of male movement was not affected by presence of female gametes. Male gametes did not move towards female gametes regardless of their proximity to each other, suggesting that the detection range for a compatible mate is very small compared to known algal examples (mostly spermatozoids and that mate recognition requires (near contact with a female gamete. We therefore investigated how male gametes move to bring insight into their search strategy and found that it was consistent with the predictions of a random-walk model with changes in direction coming from an even distribution. We further investigated the type of random walk by determining the best-fit distribution on the tail of the move length distribution and found it to be consistent with a truncated power law distribution with an exponent of 2.34. Although consistent with a Lévy walk search pattern, the range of move lengths in the tail was too narrow for Lévy properties to emerge and so would be best described as Brownian motion. This is somewhat surprising because female gametes were often outnumbered by male gametes, thus contrary to the assumption that a Brownian search mode may be most optimal with an abundant target resource. This is also the first mathematically analysed search pattern of a non-flagellated protistan gamete, supporting the notion that principles of Brownian motion have wide application in biology.

  17. Morphological evidence by scanning electron microscopy of excretion of metacyclic forms of Trypanosoma cruzi in vector's urine

    Directory of Open Access Journals (Sweden)

    Rodrigo Zeledon

    1988-09-01

    Full Text Available Comparision by scanning electron microscopy (SEM of Trypanosoma cruzi flagellates attached to the cuticle of the rectal gland of infected Dipetalogaster maxima nymphs, showed marked differences before amd after feeding. Before feeding numerous metacyclic trypomastigotes were observed among the abundant epimastigotes that formed the carpet of flagellates. On the other hand, in insects that were allowed to urinate for 24 hours after a meal, the metacyclics were scarce,indicating that they had been detached by the urine flow. An asymetric type of cell division, probably originating both an epi-and a trypomastigote, was occasionally observed. The occurrence of swellings at different levels of the flagella of epimastigotes suggests that secondary sites of attachment may be common.Observando-se, em microscopia eletrônica de varedura, formas flageladas do Trypanosoma cruzi presas a cutícula da glândula retal de ninfas infectadas de Dipetalogaster maxima verificaram-se nítidas diferenças antes e depois da alimentação. Antes, viam-se numerosos tripomastigotas metacíclicos entre os abundantes epimastigotas que formavam o tapete de flagelados, ao passo que nos insetos que urinavam dentro das 24 horas após o repasto os metacíclicos eram raros, indicando que haviam sido desprendidos pelo fluxo urinário. Foi notado, as vezes, um tipo assimétrico de divisão celular, originando um epi e um tripomastigota. Nos flagelados dos epimastigotas a presença de dilatações a diferentes níveis sugere que lugares secundários de aderência podem ser comuns.

  18. Temporal variability of the microbial food web (viruses to ciliates under the influence of the Black Sea Water inflow (N. Aegean, E. Mediterranean

    Directory of Open Access Journals (Sweden)

    A. GIANNAKOUROU

    2014-12-01

    Full Text Available Τhe entire pelagic microbial food web was studied during the winter-spring period in the frontal area of the North Aegean Sea. Abundance of viruses, heterotrophic bacteria, cyanobacteria, auto- and hetero-trophic flagellates, and ciliates, as well as bacterial production, were measured at three stations (MD1, MD2, MD3 situated along a N-S transect between the area directly influenced by the inflowing Black Sea water and the area covered by the Levantine water. Samples were collected in December 2009, and January, March, April, and May 2011. Station MD1 exhibited the highest values of abundance and integrated biomass of all microbial groups and bacterial production during all months, and MD3 the lowest. Bacteria dominated the total integrated biomass at all stations and months, followed by cyanobacteria, auto-, hetero-trophic flagellates and ciliates. On a temporal scale, the microbial food web was less important in March as all microbial parameters at all stations showed the lowest values. After the phytoplankton bloom in March, the heterotrophic part of the microbial food web (mainly strongly increased, though the intensity of the phenomenon was diminished from North to South. Pico-sized plankton was found to be heterotrophic whereas nanoplankton was autotrophic. It seems that the influence of the Black Sea water on station MD1, permanent throughout the study period of early winter to late spring, was reflected in all microbial populations studied, and produced a more productive pelagic food web system, with potential consequences for the upper trophic levels.

  19. Shiitake dermatitis recorded by French Poison Control Centers - new case series with clinical observations.

    Science.gov (United States)

    Boels, D; Landreau, A; Bruneau, C; Garnier, R; Pulce, C; Labadie, M; de Haro, L; Harry, P

    2014-07-01

    Shiitake (Lentinula edodes) is an edible mushroom which was initially grown in Japan and China and is now sold on the European market. Flagellate erythema may arise following shiitake consumption and was first described in Japan in 1974. This paper reports a French shiitake dermatitis case series. The findings of retrospective study of shiitake dermatitis cases, reported to French Poison Control Centres (PCC) from January 2000 to December 2013, are reported. Among 32 exposed patients, 15 presented flagellate urticarial lesions after raw shiitake consumption. The first case of this series was reported in 2006 and the last nine cases were reported as of 2012. After shared meals, no symptoms were reported among guests, who preferred cooked shiitake to the raw mushroom. In this series, rashes appeared 12 h to 5 days (median: 24 h) after raw shiitake ingestion. Linear and itchy urticarial lesions formed on the trunk, arms, and legs within a few hours and persisted for 3-21 days. In four cases, rash and pruritus were either triggered or worsened by sun exposure. Eleven patients received corticosteroids, antihistamines, or both. All patients completely recovered. Due to the rapidly increasing consumption of exotic food in Western countries, it is no surprise that cases of shiitake dermatitis are now appearing in Europe. The mechanism of shiitake dermatitis is thought to be toxic and due to lentinan, a polysaccharide component of the mushroom. There is no specific validated treatment for shiitake dermatitis. Health professionals and the general population should be aware of both the risk associated with raw shiitake consumption and of the good prognosis of this very spectacular and uncomfortable toxic dermatitis.

  20. Phytoplankton communities and acclimation in a cyclonic eddy in the southwest Indian Ocean

    Science.gov (United States)

    Barlow, R.; Lamont, T.; Gibberd, M.-J.; Airs, R.; Jacobs, L.; Britz, K.

    2017-06-01

    A study of phytoplankton in a cyclonic eddy was undertaken in the Mozambique Basin between Madagascar and southern Africa during austral winter. CHEMTAX analysis of pigment data indicated that the community comprised mainly haptophytes and diatoms, with Prochlorococcus, prasinophytes and pelagophytes also being prominent to the east and west of the eddy. There was little difference in community structure, chlorophyll-specific absorption [a*ph(440)] and pigment:TChla ratios between the surface and the sub-surface chlorophyll maximum (SCM), reflecting acclimation to fluctuating light conditions in a well mixed upper layer. Values for a*ph(440) were low for diatom dominance, high where prokaryote proportion was high, and intermediate for flagellate dominated communities. Chlorophyll c and fucoxanthin:TChla ratios were elevated over most of the eddy, while 19‧-hexanoyloxyfucoxanthin ratios increased in the eastern and western sectors. In a community comprising mainly flagellates and Prochlorococcus to the west of the eddy, there was high a*ph(440) at the surface and elevated ratios for divinyl chlorophyll a, chlorophyll b and 19‧-hexanoyloxyfucoxanthin at the SCM. An increase in diadinoxanthin:TChla ratios and a decline in the quantum efficiency of photochemistry in PSII under high light conditions, indicated some photoprotection and photoinhibition at the surface even in a well mixed environment. Diadinoxanthin was the main photoprotective carotenoid within the eddy, while zeaxanthin was the dominant photoprotective pigment outside the eddy. The results of this study will be useful inputs into appropriate remote sensing models for estimating primary production and the size class distribution of phytoplankton in eddies in the southwest Indian Ocean.

  1. Retrospective of fossil dinoflagellate studies in Brazil: their relationship with the evolution of petroleum exploration in the Cretaceous of continental margin basins; Historico do estudo de dinoflagelados fosseis no Brasil: sua relacao com a evolucao da exploracao petrolifera no Cretaceo das bacias da margem continental

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Mitsuru; Lana, Cecilia Cunha [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Gerencia de Bioestratigrafia e Paleoecologia]. E-mail: arai@cenpes.petrobras.com.br

    2004-05-01

    Palynostratigraphy of the Brazilian Cretaceous was mainly based on terrestrial palynomorphs (mostly spores and pollen grains) until the end of the nineteen eighties. This was so because, for several decades, petroleum exploration in Brazil was focused on the essentially non marine sediments of the Reconcavo Basin. During the nineteen sixties, PETROBRAS extended oil exploration to the Brazilian continental shelf (offshore areas). Nevertheless, at that time the company did not invest immediately in marine palynostratigraphy, because it was believed that bio stratigraphic schemes based on foraminifera and calcareous nanno fossils would be more efficient than palynology in marine sequences. This belief changed only in the seventies, when commercial oil reservoirs were discovered in the Campos Basin, within the Macae Formation, a rock unit deposited in a carbonate shelf environment. Its environmental conditions were certainly hostile to the development and post-mortem preservation of foraminifera and calcareous nanno fossil-producing algae. As a result, no more than two or three bio zones could be identified in the Macae carbonate section on the basis of such organisms. Besides, carbonate shelf sediments, subject to only minor terrigenous input, are usually poor in terrestrial palynomorphs. On the other hand, the palynological content of some Macae strata consists mainly (up to 100%) of such marine palynomorphs as dino flagellates, acritarchs e palynoforaminifera. Consequently, PETROBRAS recognized the importance of developing a zonal framework based on these organisms. The first Cretaceous dinoflagellate zonation in Brazil was erected in 1976, and since the nineteen eighties, marine Cretaceous palynostratigraphy has made significant advances mainly due to the use of dino flagellates. Hundreds of Cretaceous dinoflagellate index species have been introduced into PETROBRAS databanks, becoming widely applicable to the bio stratigraphy of all Brazilian continental margin

  2. Environmental controls on phytoplankton community composition in the Thames plume, U.K.

    Science.gov (United States)

    Weston, Keith; Greenwood, Naomi; Fernand, Liam; Pearce, David J.; Sivyer, David B.

    2008-11-01

    The aim of this study was to investigate controls on the phytoplankton community composition and biogeochemistry of the estuarine plume zone of the River Thames, U.K. using an instrumented moored buoy for in situ measurements and preserved sample collection, and laboratory-based measurements from samples collected at the same site. Instrumentation on the moored buoy enabled high frequency measurements of a suite of environmental variables including in situ chlorophyll, water-column integrated irradiance, macronutrients throughout an annual cycle for 2001 e.g. nitrate and silicate, and phytoplankton biomass and species composition. The Thames plume region acts as a conduit for fluvial nutrients into the wider southern North Sea with typical winter concentrations of 45 μM nitrate, 17 μM silicate and 2 μM phosphate measured. The spring bloom resulted from water-column integrated irradiance increasing above 60 W h m - 2 d - 1 and was initially dominated by a diatom bloom mainly composed of Nitzschia sp. and Odontella sinesis. The spring bloom then switched after ˜ 30 days to become dominated by the flagellate Phaeocystis reaching a maximum chlorophyll concentration of 37.8 μg L - 1 . During the spring bloom there were high numbers of the heterotrophic dinoflagellates Gyrodinium spirale and Katodinium glaucum that potentially grazed the phytoplankton bloom. This diatom-flagellate switch was predicted to be due to a combination of further increasing water-column integrated irradiance > 100 W h m - 2 d - 1 and/or silicate reaching potentially limiting concentrations (nutrient and phytoplankton processing and transport to the southern North Sea. The use of a combination of moorings and ship-based sampling was essential in understanding the factors influencing nutrient transport, phytoplankton biomass and species composition in this shelf sea plume region.

  3. Contrasting response to nutrient manipulation in Arctic mesocosms are reproduced by a minimum microbial food web model.

    Science.gov (United States)

    Larsen, Aud; Egge, Jorun K; Nejstgaard, Jens C; Di Capua, Iole; Thyrhaug, Runar; Bratbak, Gunnar; Thingstad, T Frede

    2015-03-01

    A minimum mathematical model of the marine pelagic microbial food web has previously shown to be able to reproduce central aspects of observed system response to different bottom-up manipulations in a mesocosm experiment Microbial Ecosystem Dynamics (MEDEA) in Danish waters. In this study, we apply this model to two mesocosm experiments (Polar Aquatic Microbial Ecology (PAME)-I and PAME-II) conducted at the Arctic location Kongsfjorden, Svalbard. The different responses of the microbial community to similar nutrient manipulation in the three mesocosm experiments may be described as diatom-dominated (MEDEA), bacteria-dominated (PAME-I), and flagellated-dominated (PAME-II). When allowing ciliates to be able to feed on small diatoms, the model describing the diatom-dominated MEDEA experiment give a bacteria-dominated response as observed in PAME I in which the diatom community comprised almost exclusively small-sized cells. Introducing a high initial mesozooplankton stock as observed in PAME-II, the model gives a flagellate-dominated response in accordance with the observed response also of this experiment. The ability of the model originally developed for temperate waters to reproduce population dynamics in a 10°C colder Arctic fjord, does not support the existence of important shifts in population balances over this temperature range. Rather, it suggests a quite resilient microbial food web when adapted to in situ temperature. The sensitivity of the model response to its mesozooplankton component suggests, however, that the seasonal vertical migration of Arctic copepods may be a strong forcing factor on Arctic microbial food webs.

  4. Cutaneous adverse reactions of chemotherapy in cancer patients: A clinicoepidemiological study

    Directory of Open Access Journals (Sweden)

    Saumita Ghosh Biswal

    2018-01-01

    Full Text Available Background: The diagnosis of cutaneous adversities in the cancer patient is especially difficult, given the complexity of their illness and combination protocols used for the treatment. The present study was undertaken to know the spectrum of cutaneous adversities in patients undergoing chemotherapy and the drug(s most commonly associated with it. Materials and Methods: A total of 1000 patients with malignancies under chemotherapy in the oncology ward and outpatient department were screened in this observational study from January 2013 to February 2015. Relevant investigations for diagnosis of malignancies under chemotherapy and dermatological disorders were carried out. Results: Three hundred and eighty-four patients presented with cutaneous adversities of chemotherapy. The most common was anagen effluvium (78.6%, followed by xerosis (4.4%, thrombophlebitis (3.1%, generalised pruritus (2.9%, melanonychia (2.9%, hand-foot syndrome (2.6%, extravasation reactions (1.8%, flagellate dermatosis (1.3%, prurigo nodularis (0.8%, exfoliation (0.5%, ichthyosis (0.5%, papulopustular rash (0.3%, bullous photodermatitis (0.3%, and Sweet's syndrome (0.3%. Chemotherapeutic drugs were mostly given in combinations. Most common drugs to cause anagen effluvium were alkylating agents in combinations, hand-foot syndrome by taxanes (docetaxel, flagellate dermatoses by antitumour antibiotics (bleomycin, and exfoliation by antimetabolites (methotrexate. The limitation of this study was to imply a specific drug as the causation of the cutaneous adversities since the chemotherapy mostly consisted of combination protocols. Therefore, we have tried to associate the drug combination itself. Conclusion: Chemotherapeutic drugs produce a range of cutaneous adversities, certain specific adversities pertaining to drugs, and their combinations have been implicated which should be looked for and managed accordingly. Knowledge of the adverse effects of anticancer drugs will help

  5. Environmental biogeography of near-surface phytoplankton in the southeast Pacific Ocean

    Science.gov (United States)

    Hardy, John; Hanneman, Andrew; Behrenfeldt, Michael; Horner, Rita

    1996-10-01

    Biogeographic interpretation of large-scale phytoplankton distribution patterns in relation to surface hydrography is essential to understanding pelagic food web dynamics and biogeochemical processes influencing global climate. We examined the abundance and biomass of phytoplankton in relation to physical and chemical parameters in the southeast Pacific Ocean. Samples were collected along longitude 110°W, between 10°N and 60°S during late austral summer. Patterns of taxa abundance and hydrographic variables were interpreted by principal components analysis. Five distinct phytohydrographic regions were identified: (i) a north equatorial region of moderate productivity dominated by small flagellates, low nitrate and low-to-moderate pCO 2; (ii) a south equatorial region characterized by high primary productivity dominated by diatoms, high nutrient levels, and relatively high pCO 2; (iii) a central gyre region characterized by low productivity dominated by small flagellates, low nitrate, and high pCO 2; (iv) a sub-Antarctic region with moderate productivity dominated by coccolithophores, moderate nitrate concentrations, and low pCO 2; and (v) an Antarctic region with high productivity dominated by diatoms, very high nitrate, and low pCO 2. Productivity and average phytoplankton cell size were positively correlated with nitrate concentration. Total phytoplankton abundance was negatively correlated with pCO 2, photosynthetically active radiation, and ultraviolet-B radiation. The interaction between phytoplankton carbon assimilation, atmospheric CO2, and the inhibitory effect of ultraviolet radiation could have implications for the global climate. These data suggest that the effects would be greatest at southern mid-latitudes (40-50°S) where present phytoplankton production and predicted future increases in UV-B are both relatively high.

  6. Enrichment of specific protozoan populations during in situ bioremediation of uranium-contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, Dawn; Giloteaux, L.; Williams, Kenneth H.; Wrighton, Kelly C.; Wilkins, Michael J.; Thompson, Courtney A.; Roper, Thomas J.; Long, Philip E.; Lovley, Derek

    2013-07-28

    The importance of bacteria in the anaerobic bioremediation of groundwater polluted with organic and/or metal contaminants is well-recognized and in some instances so well understood that modeling of the in situ metabolic activity of the relevant subsurface microorganisms in response to changes in subsurface geochemistry is feasible. However, a potentially significant factor influencing bacterial growth and activity in the subsurface that has not been adequately addressed is protozoan predation of the microorganisms responsible for bioremediation. In field experiments at a uranium-contaminated aquifer located in Rifle, CO, acetate amendments initially promoted the growth of metal-reducing Geobacter species followed by the growth of sulfate-reducers, as previously observed. Analysis of 18S rRNA gene sequences revealed a broad diversity of sequences closely related to known bacteriovorous protozoa in the groundwater prior to the addition of acetate. The bloom of Geobacter species was accompanied by a specific enrichment of sequences most closely related to the amoeboid flagellate, Breviata anathema, which at their peak accounted for over 80% of the sequences recovered. The abundance of Geobacter species declined following the rapid emergence of B. anathema. The subsequent growth of sulfate-reducing Peptococcaceae was accompanied by another specific enrichment of protozoa, but with sequences most similar to diplomonadid flagellates from the family Hexamitidae, which accounted for up to 100% of the sequences recovered during this phase of the bioremediation. These results suggest a prey-predator response with specific protozoa responding to increased availability of preferred prey bacteria. Thus, quantifying the influence of protozoan predation on the growth, activity, and composition of the subsurface bacterial community is essential for predictive modeling of in situ uranium bioremediation strategies.

  7. Screening for unicellular algae as possible bioassay organisms for monitoring marine water samples.

    Science.gov (United States)

    Millán de Kuhn, Rosmary; Streb, Christine; Breiter, Roman; Richter, Peter; Neesse, Thomas; Häder, Donat-Peter

    2006-08-01

    ECOTOX is an automatic early warning system to monitor potential pollution of freshwater, municipal or industrial waste waters or aquatic ecosystems. It is based on a real time image analysis of the motility and orientation parameters of the unicellular, photosynthetic flagellate Euglena gracilis. In order to widen the use of the device to marine habitats and saline waters nine marine flagellates were evaluated as putative bioassay organisms, viz. Dunaliella salina, Dunaliella viridis, Dunaliella bardawil, Prorocentrum minimum Kattegat, P. minimum Lissabon, Tetraselmis suecica, Heterocapsa triquetra, Gyrodinium dorsum and Cryptomonas maculata. Because of their slow growth the last three strains were excluded from further evaluation. Selection criteria were ease of culture, density of cell suspension, stability of motility and gravitactic orientation. The sensitivity toward toxins was tested using copper(II) ions. The instrument allows the user to automatically determine effect-concentration (EC) curves from which the EC(50) values can be calculated. For the interpretation of the EC curves a sigmoid logistic model was proposed which proved to be satisfactory for all tested strains. The inhibition of the motility was considered as the most appropriate movement parameter as an endpoint. The Dunaliella species had the lowest sensitivity to copper with EC(50) values of 220, 198 and 176 mg/L for D. salina, D. bardawil and D. viridis, respectively, followed by T. suecica with an EC(50) value of 40 mg/L. The Prorocentrum species were found to be the most sensitive with an EC(50) value of 13.5 mg/L for P. minimum Lissabon and 7.5 mg/L for P. minimum Kattegat.

  8. Not all are free-living: high-throughput DNA metabarcoding reveals a diverse community of protists parasitizing soil metazoa.

    Science.gov (United States)

    Geisen, S; Laros, I; Vizcaíno, A; Bonkowski, M; de Groot, G A

    2015-09-01

    Protists, the most diverse eukaryotes, are largely considered to be free-living bacterivores, but vast numbers of taxa are known to parasitize plants or animals. High-throughput sequencing (HTS) approaches now commonly replace cultivation-based approaches in studying soil protists, but insights into common biases associated with this method are limited to aquatic taxa and samples. We created a mock community of common free-living soil protists (amoebae, flagellates, ciliates), extracted DNA and amplified it in the presence of metazoan DNA using 454 HTS. We aimed at evaluating whether HTS quantitatively reveals true relative abundances of soil protists and at investigating whether the expected protist community structure is altered by the co-amplification of metazoan-associated protist taxa. Indeed, HTS revealed fundamentally different protist communities from those expected. Ciliate sequences were highly over-represented, while those of most amoebae and flagellates were under-represented or totally absent. These results underpin the biases introduced by HTS that prevent reliable quantitative estimations of free-living protist communities. Furthermore, we detected a wide range of nonadded protist taxa probably introduced along with metazoan DNA, which altered the protist community structure. Among those, 20 taxa most closely resembled parasitic, often pathogenic taxa. Therewith, we provide the first HTS data in support of classical observational studies that showed that potential protist parasites are hosted by soil metazoa. Taken together, profound differences in amplification success between protist taxa and an inevitable co-extraction of protist taxa parasitizing soil metazoa obscure the true diversity of free-living soil protist communities. © 2015 John Wiley & Sons Ltd.

  9. Plant exudates promote PCB degradation by a rhodococcal rhizobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Toussaint, Jean-Patrick; Pham, Thi Thanh My; Barriault, Diane; Sylvestre, Michel [Instiut National de la Recherche Scientifique INRS, Laval, QC (Canada). Inst. Armand-Frappier

    2012-09-15

    Rhodococcus erythropolis U23A is a polychlorinated biphenyl (PCB)-degrading bacterium isolated from the rhizosphere of plants grown on a PCB-contaminated soil. Strain U23A bphA exhibited 99% identity with bphA1 of Rhodococcus globerulus P6. We grew Arabidopsis thaliana in a hydroponic axenic system, collected, and concentrated the plant secondary metabolite-containing root exudates. Strain U23A exhibited a chemotactic response toward these root exudates. In a root colonizing assay, the number of cells of strain U23A associated to the plant roots (5.7 x 105 CFU g{sup -1}) was greater than the number remaining in the surrounding sand (4.5 x 104 CFU g{sup -1}). Furthermore, the exudates could support the growth of strain U23A. In a resting cell suspension assay, cells grown in a minimal medium containing Arabidopsis root exudates as sole growth substrate were able to metabolize 2,3,4'- and 2,3',4-trichlorobiphenyl. However, no significant degradation of any of congeners was observed for control cells grown on Luria-Bertani medium. Although strain U23A was unable to grow on any of the flavonoids identified in root exudates, biphenyl-induced cells metabolized flavanone, one of the major root exudate components. In addition, when used as co-substrate with sodium acetate, flavanone was as efficient as biphenyl to induce the biphenyl catabolic pathway of strain U23A. Together, these data provide supporting evidence that some rhodococci can live in soil in close association with plant roots and that root exudates can support their growth and trigger their PCB-degrading ability. This suggests that, like the flagellated Gram-negative bacteria, non-flagellated rhodococci may also play a key role in the degradation of persistent pollutants. (orig.)

  10. Seasonal variations of phytoplankton dynamics in Nunatsiavut fjords (Labrador, Canada) and their relationships with environmental conditions

    Science.gov (United States)

    Simo-Matchim, Armelle-Galine; Gosselin, Michel; Blais, Marjolaine; Gratton, Yves; Tremblay, Jean-Éric

    2016-04-01

    We assessed phytoplankton dynamics and its environmental control in four Labrador fjords (Nachvak, Saglek, Okak, and Anaktalak) during summer, early fall and late fall. Primary production and chlorophyll a (chl a) biomass were measured at seven optical depths, including the depth of subsurface chl a maximum (SCM). Phytoplankton abundance, size structure and taxonomy were determined at the SCM. Principal component analysis and non-metric multidimensional scaling were used to analyze relationships between production, biomass and community composition in relation to environmental variables. We observed a marked seasonal variability, with significant differences in phytoplankton structure and function between summer and fall. Surprisingly, primary production and chl a biomass were not significantly different from one fjord to another. The highest values of primary production (1730 mg C m- 2 day- 1) and chl a biomass (96 mg chl a m- 2) were measured during the summer bloom, and those high values indicate that Labrador fjords are highly productive ecosystems. The summer community showed relatively high abundance of nanophytoplankton (2-20 μm) while the fall community was characterized by low primary production and chl a biomass as well as relatively high abundance of picophytoplankton (< 2 μm). The low value of carbon potentially exported out of the euphotic zone throughout the study (≤ 31% of total primary production) suggests that phytoplankton production was mainly grazed by microzooplankton rather than being exported to greater depths. We observed a mixed assemblage of diatoms and flagellates in summer, whereas the fall community was largely dominated by flagellates. Seasonal variations in phytoplankton dynamics were mainly controlled by the strength of the vertical stratification and by the large differences in day length due to the northerly location of Labrador fjords. This study documents for the very first time phytoplankton structure and function in

  11. Chemical Composition, Antimicrobial Activity, and Mode of Action of Essential Oils against Paenibacillus larvae, Etiological Agent of American Foulbrood on Apis mellifera.

    Science.gov (United States)

    Pellegrini, María C; Alonso-Salces, Rosa M; Umpierrez, María L; Rossini, Carmen; Fuselli, Sandra R

    2017-04-01

    This study aimed to characterize the chemical composition of Aloysia polystachia, Acantholippia seriphioides, Schinus molle, Solidago chilensis, Lippia turbinata, Minthostachys mollis, Buddleja globosa, and Baccharis latifolia essential oils (EOs), and to evaluate their antibacterial activities and their capacity to provoke membrane disruption in Paenibacillus larvae, the bacteria that causes the American Foulbrood (AFB) disease on honey bee larvae. The relationship between the composition of the EOs and these activities on P. larvae was also analyzed. Monoterpenes were the most abundant compounds in all EOs. All EOs showed antimicrobial activity against P. larvae and disrupted the cell wall and cytoplasmic membrane of P. larvae provoking the leakage of cytoplasmic constituents (with the exception of B. latifolia EO). While, the EOs' antimicrobial activity was correlated most strongly to the content of pulegone, carvone, (Z)-β-ocimene, δ-cadinene, camphene, terpinen-4-ol, elemol, β-pinene, β-elemene, γ-cadinene, α-terpineol, and bornyl acetate; the volatiles that better explained the membrane disruption were carvone, limonene, cis-carvone oxide, pentadecane, trans-carvyl acetate, trans-carvone oxide, trans-limonene oxide, artemisia ketone, trans-carveol, thymol, and γ-terpinene (positively correlated) and biciclogermacrene, δ-2-carene, verbenol, α-pinene, and α-thujene (negatively correlated). The studied EOs are proposed as natural alternative means of control for the AFB disease. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  12. Contribution to the knowledge of the lichen biota of Bolivia. 8

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    Flakus Adam

    2016-07-01

    Full Text Available This paper presents new records of 135 lichen taxa in Bolivia. Two species, Myriotrema laeviusculum (Nyl. Hale and Graphis tenoriensis Chaves & Lücking, are new for the Southern Hemisphere; two, Cladonia uncialis (L. Weber ex F. H. Wigg. and Thelocarpon laureri (Flot. Nyl., are new for South America; and 27 species are new for Bolivia: Acanthotrema brasilianum (Hale Frisch, Bulbothrix laevigatula (Nyl. Hale, B. leprieurii Aubel, Canoparmelia salacinifera (Hale Hale, Catolechia wahlenbergii (Flot. ex Ach. Körb., Chapsa alborosella (Nyl. Frisch, Coccocarpia dissecta Swinscow & Krog, Graphis apertoinspersa Rivas Plata & Lücking, G. cinerea Fée, G. globosa (Fée Spreng., G. haleana R. C. Harris, G. marginata Raddi, G. pilarensis Cáceres & Lücking, G. striatula (Ach. Spreng., Hemithecium oryzaeforme (Fée Staiger, Hypotrachyna protochlorina Sipman, Elix & T. H. Nash, H. sinuosella Elix, T. H. Nash & Sipman, H. tariensis Elix, Parmeliella isidiopannosa Jørg., Parmotrema conferendum Hale, P. enteroxanthum Hale, P. laciniellum (Ferraro & Elix Blanco et al., P. pilosum (Stizenb. Krog & Swinscow, P. recipiendum (Nyl. Hale, P. ruptum (Lynge Hale ex DePriest & Hale, Pyxine pungens Zahlbr. and Xanthoparmelia substenophylloides Hale. Notes on distribution are provided for the species. Bulbothrix goebelii (Zenker Hale is excluded from the list of Bolivian lichens; the record is referred to B. laevigatula.

  13. From ratites to rats: the size of fleshy fruits shapes species' distributions and continental rainforest assembly.

    Science.gov (United States)

    Rossetto, Maurizio; Kooyman, Robert; Yap, Jia-Yee S; Laffan, Shawn W

    2015-12-07

    Seed dispersal is a key process in plant spatial dynamics. However, consistently applicable generalizations about dispersal across scales are mostly absent because of the constraints on measuring propagule dispersal distances for many species. Here, we focus on fleshy-fruited taxa, specifically taxa with large fleshy fruits and their dispersers across an entire continental rainforest biome. We compare species-level results of whole-chloroplast DNA analyses in sister taxa with large and small fruits, to regional plot-based samples (310 plots), and whole-continent patterns for the distribution of woody species with either large (more than 30 mm) or smaller fleshy fruits (1093 taxa). The pairwise genomic comparison found higher genetic distances between populations and between regions in the large-fruited species (Endiandra globosa), but higher overall diversity within the small-fruited species (Endiandra discolor). Floristic comparisons among plots confirmed lower numbers of large-fruited species in areas where more extreme rainforest contraction occurred, and re-colonization by small-fruited species readily dispersed by the available fauna. Species' distribution patterns showed that larger-fruited species had smaller geographical ranges than smaller-fruited species and locations with stable refugia (and high endemism) aligned with concentrations of large fleshy-fruited taxa, making them a potentially valuable conservation-planning indicator. © 2015 The Author(s).

  14. An original method for producing acetaldehyde and diacetyl by yeast fermentation

    Directory of Open Access Journals (Sweden)

    Irina Rosca

    Full Text Available Abstract In this study a natural culture medium that mimics the synthetic yeast peptone glucose medium used for yeast fermentations was designed to screen and select yeasts capable of producing high levels of diacetyl and acetaldehyde. The presence of whey powder and sodium citrate in the medium along with manganese and magnesium sulfate enhanced both biomass and aroma development. A total of 52 yeasts strains were cultivated in two different culture media, namely, yeast peptone glucose medium and yeast acetaldehyde-diacetyl medium. The initial screening of the strains was based on the qualitative reaction of the acetaldehyde with Schiff's reagent (violet color and diacetyl with Brady's reagent (yellow precipitate. The fermented culture media of 10 yeast strains were subsequently analyzed by gas chromatography to quantify the concentration of acetaldehyde and diacetyl synthesized. Total titratable acidity values indicated that a total titratable acidity of 5.5 °SH, implying culture medium at basic pH, was more favorable for the acetaldehyde biosynthesis using strain D15 (Candida lipolytica; 96.05 mg L-1 acetaldehyde while a total titratable acidity value of 7 °SH facilitated diacetyl flavor synthesis by strain D38 (Candida globosa; 3.58 mg L-1 diacetyl. Importantly, the results presented here suggest that this can be potentially used in the baking industry.

  15. Domestication of a Mesoamerican cultivated fruit tree, Spondias purpurea.

    Science.gov (United States)

    Miller, Allison; Schaal, Barbara

    2005-09-06

    Contemporary patterns of genetic variation in crops reflect historical processes associated with domestication, such as the geographic origin(s) of cultivated populations. Although significant progress has been made in identifying several global centers of domestication, few studies have addressed the issue of multiple origins of cultivated plant populations from different geographic regions within a domestication center. This study investigates the domestication history of jocote (Spondias purpurea), a Mesoamerican cultivated fruit tree. Sequences of the chloroplast spacer trnG-trnS were obtained for cultivated and wild S. purpurea trees, two sympatric taxa (Spondias mombin var. mombin and Spondias radlkoferi), and two outgroups (S. mombin var. globosa and Spondias testudinus). A phylogeographic approach was used and statistically significant associations of clades and geographical location were tested with a nested clade analysis. The sequences confirm that wild populations of S. purpurea are the likely progenitors of cultivated jocote trees. This study provides phylogeographic evidence of multiple domestications of this Mesoamerican cultivated fruit tree. Haplotypes detected in S. purpurea trees form two clusters, each of which includes alleles recovered in both cultivated and wild populations from distinct geographic regions. Cultivated S. purpurea populations have fewer unique trnG-trnS alleles than wild populations; however, five haplotypes were absent in the wild. The presence of unique alleles in cultivation may reflect contemporary extinction of the tropical dry forests of Mesoamerica. These data indicate that some agricultural habitats may be functioning as reservoirs of genetic variation in S. purpurea.

  16. Polonium-210 activity concentration, transfer and dose to certain invertebrates found in the vicinity of the Kudankulam Nuclear Power Project, Tamil Nadu, India

    International Nuclear Information System (INIS)

    Benjamin, J.; Wesley, S.G.; Rajan, M.P.

    2013-01-01

    Invertebrates are significant reference organisms, and some of them tend to accumulate certain radionuclides in increased levels. It is imperative that the levels of radionuclides are measured in certain organism in the vicinity of any major nuclear power project before its commissioning; hence, this study was carried out in the surroundings of the Kudankulam Nuclear Power Project site. The natural radionuclide polonium-210 having affinity to the organic matter in the soil and to the protein content of the animals, is very significant as it delivers a high internal dose to the organisms. The activity concentration of this radionuclide, its transfer and dose were assessed in two terrestrial (earthworm, Pheretima posthuma and land snail, Trachea vittata) and two aquatic (apple snail, Pila globosa and bivalve mollusc, Lamellidens marginalis) invertebrates. The activity concentration of 210 Po was found to be the highest in the earthworm and the lowest in the land snail. The per-animal dose due to 210 Po was the highest for the apple snail and the lowest for the earthworm. The results indicate that 210 Po does not constitute a significant radiological threat to the organisms. (author)

  17. Malassezia intra-specific diversity and potentially new species in the skin microbiota from Brazilian healthy subjects and seborrheic dermatitis patients.

    Directory of Open Access Journals (Sweden)

    Renan Cardoso Soares

    Full Text Available Malassezia yeasts are part of the resident cutaneous microbiota, and are also associated with skin diseases such as seborrheic dermatitis (SD. The role these fungi play in skin diseases and why they are pathogenic for only some individuals remain unclear. This study aimed to characterize Malassezia microbiota from different body sites in healthy and SD subjects from Brazil. Scalp and forehead samples from healthy, mild SD and severe SD subjects were collected. Non-scalp lesions from severe SD patients were also sampled. 5.8S rDNA/ITS2 amplicons from Malassezia sp. were analyzed by RFLP and sequencing. Results indicate that Malassezia microbiota did not group according to health condition or body area. Phylogenetic analysis revealed that three groups of sequences did not cluster together with any formally described species, suggesting that they might belong to potential new species. One of them was found in high proportions in scalp samples. A large variety of Malassezia subtypes were detected, indicating intra-specific diversity. Higher M. globosa proportions were found in non-scalp lesions from severe SD subjects compared with other areas, suggesting closer association of this species with SD lesions from areas other than scalp. Our results show the first panorama of Malassezia microbiota in Brazilian subjects using molecular techniques and provide new perspectives for further studies to elucidate the association between Malassezia microbiota and skin diseases.

  18. The Ecological Genomics of Fungi: Repeated Elements in Filamentous Fungi with a Focus on Wood-Decay Fungi

    Energy Technology Data Exchange (ETDEWEB)

    Murat, Claude [INRA, Nancy, France; Payen, Thibaut [INRA, Nancy, France; Petitpierre, Denis [INRA, Nancy, France; Labbe, Jessy L [ORNL

    2013-01-01

    In the last decade, the genome of several dozen filamentous fungi have been sequenced. Interestingly, vast diversity in genome size was observed (Fig. 2.1) with 14-fold differences between the 9 Mb of the human pathogenic dandruff fungus (Malassezia globosa; Xu, Saunders, et al., 2007) and the 125 Mb of the ectomycorrhizal black truffle of P rigord (Tuber melanosporum; Martin, Kohler, et al., 2010). Recently, Raffaele and Kamoun (2012) highlighted that the genomes of several lineages of filamentous plant pathogens have been shaped by repeat-driven expansion. Indeed, repeated elements are ubiquitous in all prokaryote and eukaryote genomes; however, their frequencies can vary from just a minor percentage of the genome to more that 60 percent of the genome. Repeated elements can be classified in two major types: satellites DNA and transposable elements. In this chapter, the different types of repeated elements and how these elements can impact genome and gene repertoire will be described. Also, an intriguing link between the transposable elements richness and diversity and the ecological niche will be highlighted.

  19. IDENTIFICATION AND CHARACTERIZATION OF CARMOVIRUS ON CARNATION (Dianthus caryophyllus L. IN WEST JAVA, INDONESIA

    Directory of Open Access Journals (Sweden)

    Erniawati Diningsih

    2015-06-01

    Full Text Available Carnation has a highly economic demand of cut flower in Indonesia. Field observations in West Java Indonesia was conducted in order to find the typical mottle symptoms that was a suspect caused by a virus disease. Identification of the virus was respectively conducted by performing ELISA test with four anti sera and characterizations held by bioassay, observing of virion particles, detecting of nucleic acid by RT-PCR and nucleotide sequencing. Total of 403 samples were collected from plants with or no virus-like symptoms. Among those all tested, 83% were found to be infected by Carnation mottle virus (CarMV, but negatively against Carnation ringspot virus (CRSV, Carnation laten virus (CLV, and Carnation vein mottle virus (CVMV antisera. By mechanical inoculation, the virus was able to infect systemically Cenopodium quinoa and locally infect on others. However on Phalaenopsis sp and Gomprena globosa, there was symptompless found. The isometric CarMV particles size was approximately 30 nm. RT-PCR using specific primers of CP gene of CarMV successfully amplified a DNA sized 1000 bp. CarMV West Java Indonesian (Idn-WJ isolates possessed the highest nucleotide and amino acid homology with CarMV from Spain and was in the same cluster with CarMV from China, Taiwan and Israel.

  20. Molecular identification of the Sporothrix schenckii complex.

    Science.gov (United States)

    Oliveira, Manoel Marques Evangelista; Almeida-Paes, Rodrigo; Gutierrez-Galhardo, Maria Clara; Zancope-Oliveira, Rosely M

    2014-01-01

    Sporothrix schenckii, an ascomycetous dimorphic organism that for over a century was recognized as the sole agent of sporotrichosis, a subcutaneous mycosis with a worldwide distribution. However, it has been proposed, based on physiologic and molecular aspects, that S. schenckii is a complex of distinct species: Sporothrix brasiliensis, Sporothrix mexicana, Sporothrix globosa, S. schenckii sensu strictu, Sporothrix luriei, and Sporothrix albicans (formerly Sporothrix pallida). Human disease has a broad range of clinical manifestations and can be classified into fixed cutaneous, lymphocutaneous, disseminated cutaneous, and extracutaneous sporotrichosis. The gold standard for the diagnosis of sporotrichosis is the culture; however, serologic, histopathologic and molecular approaches have been recently adopted for the diagnosis of this mycosis. Few molecular methods have been applied to the diagnosis of sporotrichosis to detect S. schenckii DNA from clinical specimens, and to identify Sporothrix spp. in culture. Until now, Sporothrix is the unique clinically relevant dimorphic fungus without an elucidated genome sequence, thus limiting molecular knowledge about the cryptic species of this complex, and the sexual form of all S. schenckii complex species. In this review we shall focus on the current diagnosis of the sporotrichosis, and discuss the current molecular tools applied to the diagnosis and identification of the Sporothrix complex species. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  1. Two-dimensional gel electrophoresis data for proteomic profiling of Sporothrix yeast cells

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    Anderson Messias Rodrigues

    2015-03-01

    Full Text Available Sporotrichosis is a chronic infection of the skin and subcutaneous tissues of human and other mammals caused by a complex of cryptic dimorphic fungi in the plant-associated order Ophiostomatales. With major differences between routes of transmission, Sporothrix infections are emerging as new threat in tropical and subtropical areas, particularly in form of outbreaks. The mechanisms underlying the pathogenesis and invasion of Sporothrix spp. are still poorly understood and many virulence factors remain unidentified. In this scenario, a global analysis of proteins expressed by clinical Sporothrix species combined with the identification of seroreactive proteins is overdue. Optimization of sample preparation and electrophoresis conditions are key steps toward reproducibility of gel-based proteomics assays. We provide the data generated using an efficient protocol of protein extraction for rapid and large-scale proteome analysis using two-dimensional gel electrophoresis. The protocol was established and optimized for pathogenic and non-pathogenic Sporothrix spp. including Sporothrix brasiliensis (CBS 132990, Sporothrix schenckii sensu stricto (CBS 132974, Sporothrix globosa (CBS 132922, and Sporothrix mexicana (CBS 120341. The data, supplied in this article, are related to the research article entitled “Immunoproteomic analysis reveals a convergent humoral response signature in the Sporothrix schenckii complex” (Rodrigues et al., 2014 [1].

  2. Sporotrichosis between 1898 and 2017: The evolution of knowledge on a changeable disease and on emerging etiological agents.

    Science.gov (United States)

    Lopes-Bezerra, Leila M; Mora-Montes, Hector M; Zhang, Yu; Nino-Vega, Gustavo; Rodrigues, Anderson Messias; de Camargo, Zoilo Pires; de Hoog, Sybren

    2018-04-01

    The description of cryptic species with different pathogenic potentials has changed the perspectives on sporotrichosis. Sporothrix schenckii causes a benign chronic subcutaneous mycosis, Sporothrix brasiliensis is highly virulent, and Sporothrix globosa mainly causes fixed cutaneous lesions. Furthermore, S. brasiliensis is the prevalent species related to cat-transmitted sporotrichosis. Sources of infection, transmission, and distribution patterns also differ between species, and variability differs between species because of different degrees of clonality. The present review article will cover several aspects of the biology of clinically relevant agents of sporotrichosis, including epidemiological aspects of emerging species. Genomic information of Sporothrix spp. is also discussed. The cell wall is an essential structure for cell viability, interaction with the environment, and the host immune cells and contains several macromolecules involved in virulence. Due to its importance, aspects of glycosylation and cell wall polysaccharides are reviewed. Recent genome data and bioinformatics analyses helped to identify specific enzymes of the biosynthetic glycosylation routes, with no homologs in mammalian cells, which can be putative targets for development of antifungal drugs. A diversity of molecular techniques is available for the recognition of the clinically relevant species of Sporothrix. Furthermore, antigens identified as diagnostic markers and putative vaccine candidates are described. Cell-mediated immunity plays a key role in controlling infection, but Sporothrix species differ in their interaction with the host. The adaptive branch of the immune response is essential for appropriate control of infection.

  3. Ostracoda (Arthropoda, Crustacea from the Riachuelo Formation, Sergipe-Alagoas Basin, Brazil, Upper Aptian-Albian

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    Lucas Silveira Antonietto

    2016-11-01

    Full Text Available The Sergipe-Alagoas Basin has one of the most complete, exposed lithological successions of the Cretaceous period in the continental margin of Brazil. It captures several phases of the evolution of the South Atlantic Ocean, including rift, gulf and drift. The upper Aptian–Albian Riachuelo Formation corresponds to the first stages of the southern proto-Atlantic Ocean invasion in that basin. The present study reviews the taxonomic identification and ecology of 39 ostracod species of this formation, proposing a new genus – Gabonorygma gen. nov. – and three new species – Praebythoceratina deltalata sp. nov., Gabonorygma sergipana gen. et sp. nov. and Brachycythere smithsoniana sp. nov. Other taxa include Conchoecia? sp. 1, Cytherella sp. 1, C. besrineensis comb. nov., Cytherelloidea aff. globosa, C. btaterensis, Bairdoppilata sp. 1, Bairdoppilata sp. 2, B. comanchensis comb. nov., B. pseudoseptentrionalis, Robsoniella falklandensis, Cetacella sp. 1, Paracypris eniotmetos, Harbinia sinuata?, H. crepata, Liasina sp. 1, Praebythoceratina amsittenensis comb. nov., P. trinodosa comb. nov., Patellacythere sp. 1, P. shimonensis comb. nov., Xestoleberis? sp. 1, Xestoleberis? sp. 2, Apatocythere? sp. 1, Neocythere? aff. pseudovanveeni, N. (Physocythere tenuis, Aracajuia antiqua comb. nov., A. benderi, A. fragilis comb. nov., Eocytheropteron sp. 1, Metacytheropteron aff. minuta, Microceratina? sp. 1, M. azazoulensis, Veenia guianensis, Algeriana? sp. 1, Quasihermanites? sp. 1 and Sergipella viviersae.

  4. Diagnostic value of nested-PCR for identification of Malassezia species in dandruff

    Science.gov (United States)

    Jusuf, N. K.; Nasution, T. A.; Ullyana, S.

    2018-03-01

    Dandruff or pityriasis simplex is a condition of abnormal occurrence of formation of yellowish white scales from the scalp. Many factors play a role in the pathogenesis of dandruff, i.e.colonization of Malassezia species. Examination of Malassezia species previously done by culture as the gold standard. However, there are various difficulties in doing the culture. Identification method with anested-polymerase chain reaction (nested-PCR) is expected to provide quickly and easily detected. This study aimedto determine the diagnostic value of nested-PCR in the identification of Malassezia species in dandruff. From 21 subjects, scales from the scalp were taken and sent to the laboratory for nested-PCR identification. Statistical analysis of diagnostic test carried out to determine sensitivity, specificity, positive predictive value, and negative predictive value. The results showed nested-PCR detected 10 sample (47.6%) positive for Malassezia species consist of M. sympodialis (23.8%); M. slooffiae (9.5%); M. furfur (4.8%); M. globosa and M. furfur (4.8%); and M. restricta and M. sympodialis (4.8%). Detection of Malassezia species by nested-PCR has 100% in sensitivity whereas the specificity was 55%. Nested-PCR test has high sensitivity. Therefore nested-PCR may be considered for a faster and simpler alternative examination in identification for Malassezia species in dandruff.

  5. Microbial and viral-like rhodopsins present in coastal marine sediments from four polar and subpolar regions

    Energy Technology Data Exchange (ETDEWEB)

    López, José L.; Golemba, Marcelo; Hernández, Edgardo; Lozada, Mariana; Dionisi, Hebe; Jansson, Janet K.; Carroll, Jolynn; Lundgren, Leif; Sjöling, Sara; Mac Cormack, Walter P.; Sobecky, Patricia

    2016-11-03

    Rhodopsins are broadly distributed. In this work, we analyzed 23 metagenomes corresponding to marine sediment samples from four regions that share cold climate conditions (Norway; Sweden; Argentina and Antarctica). In order to investigate the genes evolution of viral rhodopsins, an initial set of 6224 bacterial rhodopsin sequences according to COG5524 were retrieved from the 23 metagenomes. After selection by the presence of transmembrane domains and alignment, 123 viral (51) and non-viral (72) sequences (>50 amino acids) were finally included in further analysis. Viral rhodopsin genes were homologs of Phaeocystis globosa virus and Organic lake Phycodnavirus. Non-viral microbial rhodopsin genes were ascribed to Bacteroidetes, Planctomycetes, Firmicutes, Actinobacteria, Cyanobacteria, Proteobacteria, Deinococcus-Thermus and Cryptophyta and Fungi. A rescreening using Blastp, using as queries the viral sequences previously described, retrieved 30 sequences (>100 amino acids). Phylogeographic analysis revealed a geographical clustering of the sequences affiliated to the viral group. This clustering was not observed for the microbial non-viral sequences. The phylogenetic reconstruction allowed us to propose the existence of a putative ancestor of viral rhodopsin genes related to Actinobacteria and Chloroflexi. This is the first report about the existence of a phylogeographic association of the viral rhodopsin sequences from marine sediments.

  6. Sporothrix schenckii COMPLEX: SUSCEPTIBILITIES TO COMBINED ANTIFUNGAL AGENTS AND CHARACTERIZATION OF ENZYMATIC PROFILES

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    Daniele Carvalho OLIVEIRA

    2015-08-01

    Full Text Available SUMMARY Sporothrix schenckiiwas reclassified as a complex encompassing six cryptic species, which calls for the reassessment of clinical and epidemiological data of these new species. We evaluated the susceptibility of Sporothrix albicans (n = 1 , S. brasiliensis (n = 6 , S. globosa (n = 1, S. mexicana(n = 1 and S. schenckii(n = 36 to terbinafine (TRB alone and in combination with itraconazole (ITZ, ketoconazole (KTZ, and voriconazole (VRZ by a checkerboard microdilution method and determined the enzymatic profile of these species with the API-ZYM kit. Most interactions were additive (27.5%, 32.5% and 5% or indifferent (70%, 50% and 52.5% for TRB+KTZ, TRB+ITZ and TRB+VRZ, respectively. Antagonisms were observed in 42.5% of isolates for the TRB+VRZ combination. Based on enzymatic profiling, the Sporothrix schenckii strains were categorized into 14 biotypes. Leucine arylamidase (LA activity was observed only for S. albicans and S. mexicana. The species S. globosaand S. mexicanawere the only species without β-glucosidase (GS activity. Our results may contribute to a better understanding of virulence and resistance among species of the genus Sporothrixin further studies.

  7. Biodeterioration of epoxy resin: a microbial survey through culture-independent and culture-dependent approaches.

    Science.gov (United States)

    Pangallo, Domenico; Bučková, Maria; Kraková, Lucia; Puškárová, Andrea; Šaková, Nikoleta; Grivalský, Tomaš; Chovanová, Katarina; Zemánková, Milina

    2015-02-01

    During the 20th century, synthetic polymers were greatly used in the field of art. In particular, the epoxy resins were used for both conservation and for creating sculptures. The biodeterioration of these polymers has not been adequately studied. The aim of this investigation was to examine the microflora responsible for the deterioration of an epoxy statue exposed to outdoor conditions. Fungal and bacterial microflora were isolated from the art object, clustered by fluorescence-ITS (internal transcribed spacer), identified by ITS and 16S rRNA sequencing and tested for their lipolytic abilities by three agar assays. Different algal, bacterial, cyanobacterial and fungal clone libraries were constructed. The surrounding airborne microflora was analyzed using culture-dependent and culture-independent approaches. The results indicated the presence, on the statue surface, of an interesting and differentiate microbial community composed of rock-inhabiting members, algal photobionts (Trebouxia spp., Chloroidium ellipsoideum and Chlorella angustoellipsoidea), Cyanobacteria (Leptolyngbya sp., Phormidium sp., Cylindrospermum stagnale, Hassallia byssoidea and Geitlerinema sp.), black yeasts related to the species Friedmanniomyces endolithicus, Pseudotaeniolina globosa, Phaeococcomyces catenatus and Catenulostroma germanicum and several plant-associated fungi. This investigation provides new information on the potential microfloral inhabitants of epoxy resin discovering a new ecological niche, occupied mainly by several members of rock-colonizing microbial species. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  8. FUNGI ISOLATED FROM THE EXCRETA OF WILD BIRDS IN SCREENING CENTERS IN PELOTAS, RS, BRAZIL

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    Josiara Furtado Mendes

    2014-12-01

    Full Text Available The identification of the fungal species belonging to the healthy microflora in animals is a precondition for the recognition of pathological processes causing them. The aim of this study was to investigate the presence of potentially pathogenic fungi in the feces of wild birds collected in Screening Centers. Samples were collected from the feces of 50 cages with different species of birds. The samples were processed according to the modified method STAIB and the plates incubated at 32 °C for up to ten days with daily observation for detection of fungal growth. The isolation of the following species was observed: Malassezia pachydermatis, Candida albicans, C. famata, C. guilliermondii, C. sphaerica, C. globosa, C. catenulata, C. ciferri, C. intermedia, Cryptococcus laurentii, Trichosporon asahii, Geotrichum klebahnii, Aspergillus spp., A. niger and Penicillium spp. Knowing the character of some opportunistic fungi is important in identifying them, facilitating the adoption of preventive measures, such as proper cleaning of cages, since the accumulation of excreta may indicate a risk for both health professionals and centers for screening public health.

  9. Mutation in Torenia fournieri Lind. UFO homolog confers loss of TfLFY interaction and results in a petal to sepal transformation.

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    Sasaki, Katsutomo; Yamaguchi, Hiroyasu; Aida, Ryutaro; Shikata, Masahito; Abe, Tomoko; Ohtsubo, Norihiro

    2012-09-01

    We identified a Torenia fournieri Lind. mutant (no. 252) that exhibited a sepaloid phenotype in which the second whorls were changed to sepal-like organs. This mutant had no stamens, and the floral organs consisted of sepals and carpels. Although the expression of a torenia class B MADS-box gene, GLOBOSA (TfGLO), was abolished in the 252 mutant, no mutation of TfGLO was found. Among torenia homologs such as APETALA1 (AP1), LEAFY (LFY), and UNUSUAL FLORAL ORGANS (UFO), which regulate expression of class B genes in Arabidopsis, only accumulation of the TfUFO transcript was diminished in the 252 mutant. Furthermore, a missense mutation was found in the coding region of the mutant TfUFO. Intact TfUFO complemented the mutant phenotype whereas mutated TfUFO did not; in addition, the transgenic phenotype of TfUFO-knockdown torenias coincided with the mutant phenotype. Yeast two-hybrid analysis revealed that the mutated TfUFO lost its ability to interact with TfLFY protein. In situ hybridization analysis indicated that the transcripts of TfUFO and TfLFY were partially accumulated in the same region. These results clearly demonstrate that the defect in TfUFO caused the sepaloid phenotype in the 252 mutant due to the loss of interaction with TfLFY. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.

  10. Potential of some aquatic plants for removal of arsenic from wastewater by green technology

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    Mohammed Barznji Dana A.

    2015-03-01

    Full Text Available Phytoremediation or green technology is counted among the successful and effective biological contaminated water treatment techniques. Basically, the concept of this green, cost-effective, simple, environmentally nondisruptive method consists in using plants and microbiological processes to reduce contaminants in the ecosystem. Different species from aquatic plants (emerged, free-floating, and submerged have been studied to mitigate toxic contaminants such as arsenic, cadmium, chromium, copper, lead, mercury, zinc, etc. Arsenic is one of the most severe toxic elements; it is widely distributed in the environment, usually found in combination with chloride, oxygen, sulphur and metal ions as a result of mineral dissolution from sedimentary or volcanic rocks and the dilution of geothermal water. The effluents from both industrial and agricultural sectors are also regarded as sources to contaminate water. From the accumulation point of view, several aquatic plants have been mentioned as good arsenic accumulators and their performance is evaluated using the green technology method. These include Spirodela polyrhiza, Wolffia globosa, Lemna gibba, L. minor, Eichhornia crassipes, Azolla caroliniana, Azolla filiculoides, Azolla pinnata, Ceratophyllum demersum and Pistia stratiotes. The up-to-date information illustrated in this review paper generates knowledge about the ability of some common aquatic plants around the globe to remediate arsenic from contaminated water.

  11. Effects of Ionizing Radiation in Atopic Patients Exposed to Radiation

    International Nuclear Information System (INIS)

    Radwan, N.K.A.

    2014-01-01

    Atopic dermatitis is a chronic relapsing inflammatory skin disease that arises most commonly during early infancy, and is characterized by severe pruritus, age-dependant skin manifestations, and a fluctuating clinical course. Hereditary, environmental and immunological factors are involved in the aetiopathogenesis of AD. Also the differentiation of helper T- cells, local cytokine profile, IgE, infectious agents and superantigens are factors identified as being involved in the pathogenesis of AD. One hundred patients with AD were selected from the outpatient clinic of the National Center for Radiation Research and Technology in Cairo, Egypt. They were divided into 2 groups; group 1 included radiation workers in the Hall of gamma irradiation unit and group 2 included workers outside controlled area and not exposed to radiation with comparable age and sex. The severity of the disease was evaluated according to the grade of atopic dermatitis. Total and specific serum IgE was measured and Complete Blood Count was also carried out. Four Malassezia species were isolated from AD patients M. globosa, M. furfur, M. sympodialis and M. obtusa. The clinical isolates consisted of two bacterial strains, S. aureus and S. epidermidis. The significant increase of AD severity seems to be more closely related to the prevalence of S. aureus and Malassezia on the skin of radiation workers. This was proved by the presence of high IgE and eosinophils in radiation workers. So, the interactions of low gamma radiation and skin seems to further complicate the risk of assessments of atopic dermatitis

  12. Identification of clinical yeasts by Vitek MS system compared with API ID 32 C.

    Science.gov (United States)

    Durán-Valle, M Teresa; Sanz-Rodríguez, Nuria; Muñoz-Paraíso, Carmen; Almagro-Moltó, María; Gómez-Garcés, José Luis

    2014-05-01

    We performed a clinical evaluation of the Vitek MS matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) system with the commercial database version 2.0 for rapid identification of medically important yeasts as compared with the conventional phenotypic method API ID 32 C. We tested 161 clinical isolates, nine isolates from culture collections and five reference strains. In case of discrepant results or no identification with one or both methods, molecular identification techniques were employed. Concordance between both methods was observed with 160/175 isolates (91.42%) and misidentifications by both systems occurred only when taxa were not included in the respective databases, i.e., one isolate of Candida etchellsii was identified as C. globosa by Vitek MS and two isolates of C. orthopsilosis were identified as C. parapsilosis by API ID 32 C. Vitek MS could not identify nine strains (5.14%) and API ID 32 C did not identify 13 (7.42%). Vitek MS was more reliable than API ID 32 C and reduced the time required for the identification of clinical isolates to only a few minutes.

  13. Seawater: an alternative grassy weed control method for post emergence herbicides in tropical turfgrass

    International Nuclear Information System (INIS)

    Uddin, M.K.; Ismail, M.R.; Juraimi, A.S.; Hamdani, S.A.

    2014-01-01

    Research was designed to reduce herbicide use by replacing post emergence herbicides with readily available sea water to control tropical turfgrass weeds. In studies evaluating the use of saline solutions for weed control, four salinity levels (0, 24, 48 and 72 dS m/sup -1/) were applied once to 30 grassy weed species, along with seashore paspalum (Paspalum vaginatum Swartz) (as a control) during December, 2007 to March, 2008. The results on injury ratings for salt tolerant weeds were categorized as highly susceptible, moderately susceptible and extremely tolerant. C. dactylon, E. indica, E. virescense, E. unioloides and I. globosa were very susceptible and found to be effectively controlled (100%) at 72 dS m/sup -1/ salinity treatment. However, two most serious weeds viz. wiry eragrostis (E. atrovirens) and lesser dropseed (S. diander), were found to be extremely tolerant, and were not controlled even at the highest salinity level of 72 dS m/sup -1/. P. vaginatum and E. atrovirens did not show significant decrease in shoot and root dry weight at highest salinity levels (72 dS m/sup -1/). The results indicate that sea water has excellent potential for sustainable control of several common grassy weeds in tropical turf. (author)

  14. Biochemical Properties of a New Cold-Active Mono- and Diacylglycerol Lipase from Marine Member Janibacter sp. Strain HTCC2649

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    Dongjuan Yuan

    2014-06-01

    Full Text Available Mono- and di-acylglycerol lipase has been applied to industrial usage in oil modification for its special substrate selectivity. Until now, the reported mono- and di-acylglycerol lipases from microorganism are limited, and there is no report on the mono- and di-acylglycerol lipase from bacteria. A predicted lipase (named MAJ1 from marine Janibacter sp. strain HTCC2649 was purified and biochemical characterized. MAJ1 was clustered in the family I.7 of esterase/lipase. The optimum activity of the purified MAJ1 occurred at pH 7.0 and 30 °C. The enzyme retained 50% of the optimum activity at 5 °C, indicating that MAJ1 is a cold-active lipase. The enzyme activity was stable in the presence of various metal ions, and inhibited in EDTA. MAJ1 was resistant to detergents. MAJ1 preferentially hydrolyzed mono- and di-acylglycerols, but did not show activity to triacylglycerols of camellia oil substrates. Further, MAJ1 is low homologous to that of the reported fungal diacylglycerol lipases, including Malassezia globosa lipase 1 (SMG1, Penicillium camembertii lipase U-150 (PCL, and Aspergillus oryzae lipase (AOL. Thus, we identified a novel cold-active bacterial lipase with a sn-1/3 preference towards mono- and di-acylglycerides for the first time. Moreover, it has the potential, in oil modification, for special substrate selectivity.

  15. Seasonal variation of the protozooplanktonic community in a tropical oligotrophic environment (Ilha Solteira reservoir, Brazil).

    Science.gov (United States)

    Mansano, A S; Hisatugo, K F; Leite, M A; Luzia, A P; Regali-Seleghim, M H

    2013-05-01

    The seasonal variation of the protozooplanktonic community (ciliates and testate amoebae) was studied in a tropical oligotrophic reservoir in Brazil, which was under the influence of two contrasting climatic seasons (rainy/warm and dry/cold). The aim of this study was to evaluate the effect of these climatic changes on physical, chemical and biological variables in the dynamic of this community. The highest mean density of total protozoans occurred in the rainy/warm season (5683.2 ind L-1), while the lowest was in the dry/cold (2016.0 ind L-1). Considering the seasonal variations, the protozoan groups that are truly planktonic, such as the oligotrichs (Spirotrichea), predominated in the dry season, whereas during the rainy season, due to the material input and resuspension of sediment, sessile protozoans of the Peritrichia group were the most important ones. The dominant protozoans were Urotricha globosa, Cothurnia annulata, Pseudodifflugia sp. and Halteria grandinella. The highest densities of H. grandinella were associated with more oxygenated and transparent water conditions, while the highest densities of C. annulata occurred in sites with high turbidity, pH and trophic state index (TSI). The study demonstrated that density and composition of protozooplanktonic species and groups of the reservoir suffered seasonal variation due to the environmental variables (mainly temperature, turbidity, water transparency, dissolved oxygen and TSI) and the biological variables (e.g. morphological characteristics, eating habits and escape strategies from predation of the species).

  16. Transference of function shapes organ identity in the dove tree inflorescence.

    Science.gov (United States)

    Vekemans, Dries; Viaene, Tom; Caris, Pieter; Geuten, Koen

    2012-01-01

    • An important evolutionary mechanism shaping the biodiversity of flowering plants is the transfer of function from one plant organ to another. To investigate whether and how transference of function is associated with the remodeling of the floral organ identity program we studied Davidia involucrata, a species with conspicuous, petaloid bracts subtending a contracted inflorescence with reduced flowers. • A detailed ontogeny enabled the interpretation of expression patterns of B-, C- and E-class homeotic MADS-box genes using qRT-PCR and in situ hybridization techniques. We investigated protein-protein interactions using yeast two-hybrid assays. • Although loss of organs does not appear to have affected organ identity in the retained organs of the reduced flowers of D. involucrata, the bracts express the B-class TM6 (Tomato MADS box gene 6) and GLOBOSA homologs, but not DEFICIENS, and the C-class AGAMOUS homolog, representing a subset of genes also involved in stamen identity. • Our results may illustrate how petal identity can be partially transferred outside the flower by expressing a subset of stamen identity genes. This adds to the molecular mechanisms explaining the diversity of plant reproductive morphology. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  17. Morphological, Molecular Identification and Their Genetic Diversity of Aquatic Plant Duckweeds in Fujian Province%福建水生植物浮萍的形态学和分子系统学鉴定及遗传多样性研究

    Institute of Scientific and Technical Information of China (English)

    叶松建; 韩冰莹; 张家明

    2017-01-01

    119 duckweed germplasms were collected in 53 cities or countries in Fujian Province.They were classified into four genera:Landoltia,Spirodela,Wolffia,and Lemna using morphological analysis based on leaf size,root and leaf number.The chloroplast atpF-atpH internal sequence and the rpS16 intron sequence were obtained by PCR amplification and sequencing.Phylogenetic analysis indicated that these germplams belong to four species:Landoltia punctata,Spirodela polyrhiza,Wolffia globosa,and Lemna aequinoctialis.Genetic diversity analysis using DnaSP 5.10.01 software showed that germplasms had rich diversity,and rpS16 presented more diversity than atpF-atpH.The nucleotide diversity of atpF-atpH and rpS16 was 0.031 53 and 0.051 23,respectively;the distinct nucleotide number per kb was 20.374 and 44.675,respectively;the population mutation rate was 0.03640 and 0.051 64,respectively,and the haplotype diversity was 0.577 and 0.617,respectively.The haplotype numbers of atpF-atpH and rpS16 were 4,2,and 2,respectively.The genetic diversity in South Fujian was higher than that in North Fujian,and the nucleotide diversity,different nucleotide number and the population mutation rate of atpF-atpH in South Fujian were twice as high as those in the North.%在福建53个市县(区)收集获得119份浮萍种质.通过叶片大小、根系和叶脉数等形态性状初步鉴定为4个属:少根紫萍属(Landohia)、多根紫萍属(Spirodela)、无根萍属(Wolffia)、浮萍属(Lemna).利用叶绿体atpF-atpH间隔序列和rpS16内含子序列进行系统发育分析.结果表明,119份浮萍种质分别属于4个种Landoltia punctata,Spirodela polyrhiza,Wolffia globosa,Lemna aequinoctialis.利用DnaSP 5.10.01软件分析结果显示,福建浮萍种质存在丰富的遗传多样性,且rpS16比atp F-atpH多样性大,两者的核苷酸多态性指数分别为0.051 23和0.031 53,每kb平均核苷酸差异数为44.675和20.374,群体突变率分别为0.051 64和0.036 40,单倍

  18. Temperature, productivity and sediment characteristics as drivers of seasonal and spatial variations of dissolved methane in the near-shore coastal areas (Belgian coastal zone, North Sea)

    Science.gov (United States)

    Borges, Alberto V.; Speeckaert, Gaëlle; Champenois, Willy; Scranton, Mary I.; Gypens, Nathalie

    2017-04-01

    The open ocean is a modest source of CH4 to the atmosphere compared to other natural and anthropogenic CH4 emissions. Coastal regions are more intense sources of CH4 to the atmosphere than open oceanic waters, in particular estuarine zones. The CH4 emission to the atmosphere from coastal areas is sustained by riverine inputs and methanogenesis in the sediments due to high organic matter (OM) deposition. Additionally, natural gas seeps are sources of CH4 to bottom waters leading to high dissolved CH4 concentrations in bottom waters (from tenths of nmol L-1 up to several µmol L-1). We report a data set of dissolved CH4 concentrations obtained at nine fixed stations in the Belgian coastal zone (Southern North Sea), during one yearly cycle, with a bi-monthly frequency in spring, and a monthly frequency during the rest of the year. This is a coastal area with multiple possible sources of CH4 such as from rivers and gassy sediments, and where intense phytoplankton blooms are dominated by the high dimethylsulfoniopropionate (DMSP) producing micro-algae Phaeocystis globosa, leading to DMSP and dimethylsulfide (DMS) concentrations. Furthermore, the BCZ is a site of important OM sedimentation and accumulation unlike the rest of the North Sea. Spatial variations of dissolved CH4 concentrations were very marked with a minimum yearly average of 9 nmol L-1 in one of the most off-shore stations and maximum yearly average of 139 nmol L-1 at one of the most near-shore stations. The spatial variations of dissolved CH4 concentrations were related to the organic matter (OM) content of sediments, although the highest concentrations seemed to also be related to inputs of CH4 from gassy sediments associated to submerged peat. In the near-shore stations with fine sand or muddy sediments with a high OM content, the seasonal cycle of dissolved CH4 concentration closely followed the seasonal cycle of water temperature, suggesting the control of methanogenesis by temperature in these OM

  19. Tomato yellow vein streak virus: relationship with Bemisia tabaci biotype B and host range Tomato yellow vein streak virus: interação com a Bemisia tabaci biótipo B e gama de hospedeiros

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    Ana Carolina Firmino

    2009-12-01

    Full Text Available The Tomato yellow vein streak virus (ToYVSV is a putative species of begomovirus, which was prevalent on tomato crops in São Paulo State, Brazil, until 2005. The objectives of this study were to evaluate the interaction between ToYVSV and its vector Bemisia tabaci biotype B and to identify alternative hosts for the virus. The minimum acquisition and inoculation access periods of ToYVSV by B. tabaci were 30 min and 10 min, respectively. Seventy five percent of tomato-test plants were infected when the acquisition and inoculation access periods were 24 h. The latent period of the virus in the insect was 16 h. The ToYVSV was retained by B. tabaci until 20 days after acquisition. First generation of adult whiteflies obtained from viruliferous females were virus free as shown by PCR analysis and did not transmit the virus to tomato plants. Out of 34 species of test-plants inoculated with ToYVSV only Capsicum annuum, Chenopodium amaranticolor, C. quinoa, Datura stramonium, Gomphrena globosa, Nicotiana clevelandii and N. tabacum cv. TNN were susceptible to infection. B. tabaci biotype B was able to acquire the virus from all these susceptible species, transmitting it to tomato plants.O Tomato yellow vein streak virus (ToYVSV é uma espécie putativa de begomovirus que infecta o tomateiro (Solanum lycopersicon em diversas regiões do Brasil onde se cultiva essa solanácea, sendo a espécie prevalente no estado de São Paulo até 2005. Estudou-se a interação do ToYVSV com a Bemisia tabaci biótipo B e identificaram-se hospedeiras alternativas deste vírus. Os períodos de acesso mínimo de aquisição (PAA e de inoculação (PAI foram de 30 min e 10 min, respectivamente. A porcentagem de plantas infectadas chegou até cerca de 75% após um PAA e PAI de 24 h. O período de latência do vírus no vetor foi de 16 horas. O ToYVSV foi retido pela B. tabaci até 20 dias após a aquisição do vírus. Não foi detectada transmissão do vírus para prog

  20. Expression of paralogous SEP-, FUL-, AG- and STK-like MADS-box genes in wild-type and peloric Phalaenopsis flowers.

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    Roberta eAcri-Nunes-Miranda

    2014-03-01

    Full Text Available The diverse flowers of Orchidaceae are the result of several major morphological transitions, among them the most studied is the differentiation of the inner median tepal into the labellum, a perianth organ key in pollinator attraction. Type A peloria lacking stamens and with ectopic labella in place of inner lateral tepals are useful for testing models on the genes specifying these organs by comparing their patterns of expression between wild-type and peloric flowers. Previous studies focused on DEFICIENS and GLOBOSA-like MADS-box genes because of their conserved role in perianth and stamen development. The ‘orchid code’ model summarizes this work and shows in Orchidaceae there are four paralogous lineages of DEFICIENS/AP3-like genes differentially expressed in each floral whorl. Experimental tests of this model showed the conserved, higher expression of genes from two specific DEF-like gene lineages is associated with labellum development. The present study tests whether eight MADS-box candidate SEP-, FUL-, AG- and STK-like genes have been specifically duplicated in the Orchidaceae and are also differentially expressed in association with the distinct flower organs of Phalaenopsis hyb. Athens. The gene trees indicate orchid-specific duplications. In a way analogous to what is observed in labellum-specific DEF-like genes, a two-fold increase in the expression of SEP3-like gene PhaMADS7 was measured in the labellum-like inner lateral tepals of peloric flowers. The overlap between SEP3-like and DEF-like genes suggests both are associated with labellum specification and similar positional cues determine their domains of expression. In contrast, the uniform messenger levels of FUL-like genes suggest they are involved in the development of all organs and their expression in the ovary suggests cell differentiation starts before pollination. As previously reported AG-like and STK-like are exclusively expressed in gynostemium and ovary, however no

  1. Comparative metagenomics approaches to characterize the soil fungal communities of western coastal region, Saudi Arabia.

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    Tarek A A Moussa

    Full Text Available A total of 145007 reads were obtained from pyrosequencing for all the 4 samples. The total count ranged from 11,301,014 (Mecca old road to 23,503,512 bp (Thuwal. A total of 460 fungal species belonging to 133 genera, 58 families, 33 orders, 13 classes and 4 phyla was identified across the four sites. The most abundant phylum at all four sites was Ascomycota followed by Basidiomycota. Four phyla (Ascomycota-99.31%, Basidiomycota-0.59%, Chytridiomycota-0.04%, Glomeromycota-0.03% were detected in Khulais. Except for Glomeromycota, all phyla were detected at Mecca old road (Ascomycota-74.26%, Basidiomycota-25.71%, Chytridiomycota-0.01% and Thuwal (Ascomycota-99.59%, Basidiomycota-0.40%, Chytridiomycota-0.002%; while only Ascomycota-90.98% and Basidiomycota-9.01% were detected in Asfan road. At the class level, Sordariomycetes was predominantly observed at Asfan road-59.88%, Khulais-68.26% and Thuwal-94.84%; while Pezizomycetes was dominant at Mecca old road-56.01%, was absent at Asfan road. Agaricomycetes was present only at Mecca old road-25.73%; while Tremellomycetes-5.77%, Malasseizomycetes-2.13% and Microbotryomycetes-1.10% were found only at Asfan road. The phylogenetic trees revealed that clear genus level differences are visible across all the four sites, with an overall predominance of Thielavia followed by Madurella, Aspergillus, and Gelasinospora. Chaetomium sp., Aspergillus caespitosus and Aspergillus sp. were found in moderate (Mecca old road and Thuwal to abundant (Asfan road and Khulais quantities. Thielavia sp., Thielavia hyalocarpa and Madurella sp. are found in moderate quantities at Khulais and Mecca old road, while in abundant levels at Asfan road and Thuwal. Fusarium equisati and F. oxysporum were detected at Thuwal and Khulais. Sordaria araneosa was present at Khulais, while Malasseiza globosa species was detected in moderate quantities across all sites except Khulais.

  2. Polimorfismos genéticos de aislamientos del género Malassezia obtenidos en Colombia de pacientes con lesión dermatológica y sin ella.

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    Adriana M. Celis

    2005-12-01

    Full Text Available Introducción. Las especies del género Malassezia se consideran levaduras oportunistas emergentes de gran importancia. Han sido asociadas a diferentes patologías dermatológicas y sistémicas de las cuales se aislan una o más especies de este género. El papel de estas levaduras en las enfermedades dermatológicas no se ha aclarado completamente, ya que la Malassezia spp. pertenece a la flora normal de la piel. Objetivo. Buscar marcadores genéticos en los aislamientos de Malassezia spp. que permitan correlacionar las lesiones dermatológicas con las especies aisladas. Materiales y métodos. Se obtuvieron 103 aislamientos de Malassezia spp. a partir de muestras de pacientes con pitiriasis versicolor, dermatitis seborreica, dermatitis seborreica en pacientes positivos para VIH, dermatitis atópica, y de individuos sanos. Para los controles se usaron ocho cepas del Centraalbureau voor Schimmelcultures (CBS, Holanda. El perfil genético se realizó utilizando la técnica de ADN polimórfico amplificado aleatorio (RAPD con tres iniciadores (OPA2, OPA4, OPA13. Los datos obtenidos se analizaron con los programas Diversity Database y SYN-TAX-PC. Resultados. Se observó heterogeneidad genética intraespecífica en Malassezia furfur, Malassezia globosa, Malassezia restricta, Malassezia slooffiae y Malassezia obtusa, mientras que Malassezia sympodialis mostró mayor homogeneidad. Conclusión. No se determinó ningún patrón genético específico mediante la técnica de RAPD para las especies de Malassezia que se pudiera relacionar con la entidad dermatológica implicada.

  3. Yeast identification in floral nectar of Mimulus aurantiacus (Invited)

    Science.gov (United States)

    Kyauk, C.; Belisle, M.; Fukami, T.

    2009-12-01

    Nectar is such a sugar-rich resource that serves as a natural habitat in which microbes thrive. As a result, yeasts arrive to nectar on the bodies of pollinators such as hummingbirds and bees. Yeasts use the sugar in nectar for their own needs when introduced. This research focuses on the identification of different types of yeast that are found in the nectar of Mimulus aurantiacus (commonly known as sticky monkey-flower). Unopened Mimulus aurantiacus flower buds were tagged at Jasper Ridge and bagged three days later. Floral nectar was then extracted and plated on potato dextrose agar. Colonies on the plates were isolated and DNA was extracted from each sample using QIAGEN DNeasy Plant Mini Kit. The DNA was amplified through PCR and ran through gel electrophoresis. The PCR product was used to clone the nectar samples into an E.coli vector. Finally, a phylogenetic tree was created by BLAST searching sequences in GenBank using the Internal Transcribed Space (ITS) locus. It was found that 18 of the 50 identified species were Candida magnifica, 14 was Candida rancensis, 6 were Crytococcus albidus and there were 3 or less of the following: Starmella bombicola, Candida floricola, Aureobasidium pullulans, Pichia kluyvera, Metschnikowa cibodaserisis, Rhodotorua colostri, and Malassezia globosa. The low diversity of the yeast could have been due to several factors: time of collection, demographics of Jasper Ridge, low variety of pollinators, and sugar concentration of the nectar. The results of this study serve as a necessary first step for a recently started research project on ecological interactions between plants, pollinators, and nectar-living yeast. More generally, this research studies the use of the nectar-living yeast community as a natural microcosm for addressing basic questions about the role of dispersal and competitive and facilitative interactions in ecological succession.

  4. Microbiomes associated with infective stages of root-knot and lesion nematodes in soil.

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    Ahmed Elhady

    Full Text Available Endoparasitic root-knot (Meloidogyne spp. and lesion (Pratylenchus spp. nematodes cause considerable damage in agriculture. Before they invade roots to complete their life cycle, soil microbes can attach to their cuticle or surface coat and antagonize the nematode directly or by induction of host plant defenses. We investigated whether the nematode-associated microbiome in soil differs between infective stages of Meloidogyne incognita and Pratylenchus penetrans, and whether it is affected by variation in the composition of microbial communities among soils. Nematodes were incubated in suspensions of five organically and two integrated horticultural production soils, recovered by sieving and analyzed for attached bacteria and fungi after washing off loosely adhering microbes. Significant effects of the soil type and nematode species on nematode-associated fungi and bacteria were revealed as analyzed by community profiling using denaturing gradient gel electrophoresis. Attached microbes represented a small specific subset of the soil microbiome. Two organic soils had very similar bacterial and fungal community profiles, but one of them was strongly suppressive towards root-knot nematodes. They were selected for deep amplicon sequencing of bacterial 16S rRNA genes and fungal ITS. Significant differences among the microbiomes associated with the two species in both soils suggested specific surface epitopes. Among the 28 detected bacterial classes, Betaproteobacteria, Bacilli and Actinobacteria were the most abundant. The most frequently detected fungal genera were Malassezia, Aspergillus and Cladosporium. Attached microbiomes did not statistically differ between these two soils. However, Malassezia globosa and four fungal species of the family Plectosphaerellaceae, and the bacterium Neorhizobium galegae were strongly enriched on M. incognita in the suppressive soil. In conclusion, the highly specific attachment of microbes to infective stages of

  5. Formation of Chromophoric Dissolved Organic Matter by Bacterial Degradation of Phytoplankton-Derived Aggregates

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    Joanna D. Kinsey

    2018-01-01

    Full Text Available Organic matter produced and released by phytoplankton during growth is processed by heterotrophic bacterial communities that transform dissolved organic matter into biomass and recycle inorganic nutrients, fueling microbial food web interactions. Bacterial transformation of phytoplankton-derived organic matter also plays a poorly known role in the formation of chromophoric dissolved organic matter (CDOM which is ubiquitous in the ocean. Despite the importance of organic matter cycling, growth of phytoplankton and activities of heterotrophic bacterial communities are rarely measured in concert. To investigate CDOM formation mediated by microbial processing of phytoplankton-derived aggregates, we conducted growth experiments with non-axenic monocultures of three diatoms (Skeletonema grethae, Leptocylindrus hargravesii, Coscinodiscus sp. and one haptophyte (Phaeocystis globosa. Phytoplankton biomass, carbon concentrations, CDOM and base-extracted particulate organic matter (BEPOM fluorescence, along with bacterial abundance and hydrolytic enzyme activities (α-glucosidase, β-glucosidase, leucine-aminopeptidase were measured during exponential growth and stationary phase (~3–6 weeks and following 6 weeks of degradation. Incubations were performed in rotating glass bottles to keep cells suspended, promoting cell coagulation and, thus, formation of macroscopic aggregates (marine snow, more similar to surface ocean processes. Maximum carbon concentrations, enzyme activities, and BEPOM fluorescence occurred during stationary phase. Net DOC concentrations (0.19–0.46 mg C L−1 increased on the same order as open ocean concentrations. CDOM fluorescence was dominated by protein-like signals that increased throughout growth and degradation becoming increasingly humic-like, implying the production of more complex molecules from planktonic-precursors mediated by microbial processing. Our experimental results suggest that at least a portion of open

  6. Hybridization among distantly related species: Examples from the polyploid genus Curcuma (Zingiberaceae).

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    Záveská, Eliška; Fér, Tomáš; Šída, Otakar; Marhold, Karol; Leong-Škorničková, Jana

    2016-07-01

    Discerning relationships among species evolved by reticulate and/or polyploid evolution is not an easy task, although it is widely discussed. The economically important genus Curcuma (ca. 120 spp.; Zingiberaceae), broadly distributed in tropical SE Asia, is a particularly interesting example of a group of palaeopolyploid origin whose evolution is driven mainly by hybridization and polyploidization. Although a phylogeny and a new infrageneric classification of Curcuma, based on commonly used molecular markers (ITS and cpDNA), have recently been proposed, significant evolutionary questions remain unresolved. We applied a multilocus approach and a combination of modern analytical methods to this genus to distinguish causes of gene tree incongruence and to identify hybrids and their parental species. Five independent regions of nuclear DNA (DCS, GAPDH, GLOBOSA3, LEAFY, ITS) and four non-coding cpDNA regions (trnL-trnF, trnT-trnL, psbA-trnH and matK), analysed as a single locus, were employed to construct a species tree and hybrid species trees using (*)BEAST and STEM-hy. Detection of hybridogenous species in the dataset was also conducted using the posterior predictive checking approach as implemented in JML. The resulting species tree outlines the relationships among major evolutionary lineages within Curcuma, which were previously unresolved or which conflicted depending upon whether they were based on ITS or cpDNA markers. Moreover, by using the additional markers in tests of plausible topologies of hybrid species trees for C. vamana, C. candida, C. roscoeana and C. myanmarensis suggested by previous molecular and morphological evidence, we found strong evidence that all the species except C. candida are of subgeneric hybrid origin. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Phylogenetic analysis reveals a high prevalence of Sporothrix brasiliensis in feline sporotrichosis outbreaks.

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    Rodrigues, Anderson Messias; de Melo Teixeira, Marcus; de Hoog, G Sybren; Schubach, Tânia Maria Pacheco; Pereira, Sandro Antonio; Fernandes, Geisa Ferreira; Bezerra, Leila Maria Lopes; Felipe, Maria Sueli; de Camargo, Zoilo Pires

    2013-01-01

    Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics of sporotrichosis occurred in Brazil due to zoonotic transmission, and cats were pointed out as key susceptible hosts. In order to understand the eco-epidemiology of feline sporotrichosis and its role in human sporotrichosis a survey was conducted among symptomatic cats. Prevalence and phylogenetic relationships among feline Sporothrix species were investigated by reconstructing their phylogenetic origin using the calmodulin (CAL) and the translation elongation factor-1 alpha (EF1α) loci in strains originated from Rio de Janeiro (RJ, n = 15), Rio Grande do Sul (RS, n = 10), Paraná (PR, n = 4), São Paulo (SP, n =3) and Minas Gerais (MG, n = 1). Our results showed that S. brasiliensis is highly prevalent among cats (96.9%) with sporotrichosis, while S. schenckii was identified only once. The genotype of Sporothrix from cats was found identical to S. brasiliensis from human sources confirming that the disease is transmitted by cats. Sporothrix brasiliensis presented low genetic diversity compared to its sister taxon S. schenckii. No evidence of recombination in S. brasiliensis was found by split decomposition or PHI-test analysis, suggesting that S. brasiliensis is a clonal species. Strains recovered in states SP, MG and PR share the genotype of the RJ outbreak, different from the RS clone. The occurrence of separate genotypes among strains indicated that the Brazilian S. brasiliensis epidemic has at least two distinct sources. We suggest that cats represent a major host and the main source of cat and human S. brasiliensis infections in Brazil.

  8. Genetic diversity and antifungal susceptibility profiles in causative agents of sporotrichosis

    Science.gov (United States)

    2014-01-01

    Background Sporotrichosis is a chronic subcutaneous mycosis of humans and animals, which is typically acquired by traumatic inoculation of plant material contaminated with Sporothrix propagules, or via animals, mainly felines. Sporothrix infections notably occur in outbreaks, with large epidemics currently taking place in southeastern Brazil and northeastern China. Pathogenic species include Sporothrix brasiliensis, Sporothrix schenckii s. str., Sporothrix globosa, and Sporothrix luriei, which exhibit differing geographical distribution, virulence, and resistance to antifungals. The phylogenetically remote species Sporothrix mexicana also shows a mild pathogenic potential. Methods We assessed a genetically diverse panel of 68 strains. Susceptibility profiles of medically important Sporothrix species were evaluated by measuring the MICs and MFCs for amphotericin B (AMB), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), posaconazole (PCZ), flucytosine (5FC), and caspofungin (CAS). Haplotype networks were constructed to reveal interspecific divergences within clinical Sporothrix species to evaluate genetically deviant isolates. Results ITC and PCZ were moderately effective against S. brasiliensis (MIC90 = 2 and 2 μg/mL, respectively) and S. schenckii (MIC90 = 4 and 2 μg/mL, respectively). PCZ also showed low MICs against the rare species S. mexicana. 5FC, CAS, and FLC showed no antifungal activity against any Sporothrix species. The minimum fungicidal concentration ranged from 2 to >16 μg/mL for AMB against S. brasiliensis and S. schenckii, while the MFC90 was >16 μg/mL for ITC, VRC, and PCZ. Conclusion Sporothrix species in general showed high degrees of resistance against antifungals. Evaluating a genetically diverse panel of strains revealed evidence of multidrug resistant phenotypes, underlining the need for molecular identification of etiologic agents to predict therapeutic outcome. PMID:24755107

  9. Asexual propagation of a virulent clone complex in a human and feline outbreak of sporotrichosis.

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    Teixeira, Marcus de Melo; Rodrigues, Anderson Messias; Tsui, Clement K M; de Almeida, Luiz Gonzaga Paulo; Van Diepeningen, Anne D; van den Ende, Bert Gerrits; Fernandes, Geisa Ferreira; Kano, Rui; Hamelin, Richard C; Lopes-Bezerra, Leila Maria; Vasconcelos, Ana Tereza Ribeiro; de Hoog, Sybren; de Camargo, Zoilo Pires; Felipe, Maria Sueli Soares

    2015-02-01

    Sporotrichosis is one of the most frequent subcutaneous fungal infections in humans and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual as no sexual stage has ever been reported in Sporothrix schenckii, Sporothrix brasiliensis, or Sporothrix globosa. We have identified the mating type (MAT) loci in the S. schenckii (strain 1099-18/ATCC MYA-4821) and S. brasiliensis (strain 5110/ATCC MYA-4823) genomes by using comparative genomic approaches to determine the mating type ratio in these pathogen populations. Our analysis revealed the presence of a MAT1-1 locus in S. schenckii while a MAT1-2 locus was found in S. brasiliensis representing genomic synteny to other Sordariomycetes. Furthermore, the components of the mitogen-activated protein kinase (MAPK)-pheromone pathway, pheromone processing enzymes, and meiotic regulators have also been identified in the two pathogens, suggesting the potential for sexual reproduction. The ratio of MAT1-1 to MAT1-2 was not significantly different from 1:1 for all three Sporothrix species, but the population of S. brasiliensis in the outbreaks originated from a single mating type. We also explored the population genetic structure of these pathogens using sequence data of two loci to improve our knowledge of the pattern of geographic distribution, genetic variation, and virulence phenotypes. Population genetics data showed significant population differentiation and clonality with a low level of haplotype diversity in S. brasiliensis isolates from different regions of sporotrichosis outbreaks in Brazil. In contrast, S. schenckii isolates demonstrated a high degree of genetic variability without significant geographic differentiation, indicating the presence of recombination. This study demonstrated that two species causing the same disease have contrasting reproductive strategies and genetic variability

  10. Ontogeny and Structure of the Pericarp of Schinus terebinthifolius Raddi (Anacardiaceae

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    Sandra Maria Carmello-Guerreiro

    2002-03-01

    Full Text Available The fruit of Schinus terebinthifolius Raddi is a globose red drupe with friable exocarp when ripe and composed of two lignified layers: the epidermis and hypodermis. The mesocarp is parenchymatous with large secretory ducts associated with vascular bundles. In the mesocarp two regions are observed: an outer region composed of only parenchymatous cells and an inner region, bounded by one or more layers of druse-like crystals of calcium oxalate, composed of parenchymatous cells, secretory ducts and vascular bundles. The mesocarp detaches itself from the exocarp due to degeneration of the cellular layers in contact with the hypodermis. The lignified endocarp is composed of four layers: the outermost layer of polyhedral cells with prismatic crystals of calcium oxalate, and the three innermost layers of sclereids in palisade.O fruto de Schinus terebinthifolius Raddi é uma drupa vermelha, globosa, com exocarpo friável quando maduro e composto de duas camadas lignificadas: a epiderme e a hipoderme. O mesocarpo é parenquimático com grandes canais secretores associados aos feixes vasculares. No mesocarpo distinguem-se duas regiões uma externa composta apenas de células parenquimáticas e uma interna, delimitada por uma ou mais camadas de células contendo cristais de oxalato de cálcio do tipo drusa, composta de células parenquimáticas, canais secretores e feixes vasculares. O mesocarpo desprende-se do exocarpo devido à degeneração das camadas celulares em contato com a hipoderme. O endocarpo é lignificado e composto de quatro camadas: uma mais externa de células poliédricas com cristais prismáticos de oxalato de cálcio e três mais internas de esclereides em paliçada.

  11. Microplanktonic community structure in a coastal system relative to a Phaeocystis bloom inferred from morphological and tag pyrosequencing methods.

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    Sébastien Monchy

    Full Text Available BACKGROUND: Massive phytoplankton blooms, like the recurrent Phaeocystis proliferation observed every year in the Eastern English Channel (EEC, have a significant influence on the overall planktonic community structure and their food web dynamics. As well as being an important area for local fisheries, the EEC is an ideal ecosystem for work on microbial diversity. This is because, although its environmental context is relatively complex, it is reasonably well understood due to several years of monitoring and morphological observations of its planktonic organisms. The objective of our study was to better understand the under-explored microbial eukaryotic diversity relative to the Phaeocystis bloom. METHODOLOGY AND PRINCIPAL FINDINGS: The community structure of microplankton (diatoms, haptophytes, ciliates and dinoflagellates was studied through morphological observations and tag pyrosequencing. During the annual Phaeocystis spring bloom, the phytoplankton biomass increased by 34-fold, while the microzooplankton biomass showed a 4-fold increase, representing on average about 4.6% of the biomass of their phytoplankton prey. Tag pyrosequencing unveiled an extensive diversity of Gymnodiniaceae, with G. spirale and G. fusiformis representing the most abundant reads. An extended diversity of Phaeocystales, with partial 18S rDNA genes sequence identity as low as 85% was found, with taxa corresponding to P. globosa, but also to unknown Phaeocystaceae. CONCLUSIONS: Morphological analyses and pyrosequencing were generally in accordance with capturing frequency shifts of abundant taxa. Tag pyrosequencing allowed highlighting the maintenance of microplankton diversity during the Phaeocystis bloom and the increase of the taxa presenting low number of reads (minor taxa along with the dominant ones in response to biotic and/or abiotic changing conditions. Although molecular approaches have enhanced our perception on diversity, it has come to light that the

  12. Modelos de regressão para estimativa da área foliar de espécies brasileiras do gênero Tillandsia L. (Bromeliaceae.

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    Patrícia Gabarra Mendonça

    2005-06-01

    Full Text Available O objetivo deste trabalho foi ajustar equações de regressão para estimativa da área foliar de Tillandsia spp. nativas do Brasil. Determinaram-se o comprimento ao longo da nervura principal (C, a largura máxima (L e a área foliar real de, no mínimo, 100 folhas de cada espécie, mantidas intactas nas plantas. Calcularam-se relações lineares existentes entre a área foliar real e as dimensões C, L e CL (produto entre o comprimento e a largura da folha. O modelo de regressão linear com intercepto foi o mais adequado, e as equações recomendadas, sendo AFE= área foliar estimada, foram: para Tillandsia carminea, AFE= 0,281188 + 0,562219 CL (R2= 0,7296; :Tillandsia dura, AFE= 0,891231 + 0,412457 CL (R2= 0,8432; Tillandsia gardneri, AFE= 2,54412 + 0,445525 CL (R2= 0,8662; Tillandsia geminiflora, AFE= 0,674484 + 0,444418 CL (R2= 0,8474; Tillandsia globosa, AFE= 1,9494 + 0,3804 CL (R2= 0,8178; Tillandsia grazielae, AFE= 0,518512 + 0,530259 CL (R2= 0,7608; Tillandsia kautskyi, AFE= 0,59338 + 0,374353 CL (R2= 0,6931; Tillandsia reclinata, AFE= 0,0379111 + 0,641623 CL (R2= 0,9169; Tillandsia stricta, AFE= 0,3937 + 0,4277 C (R2= 0,8661, ou AFE= 1,21336 + 0,385727 CL (R2= 0,8607; Tillandsia tenuifolia, AFE= 0,991226 + 0,402221 CL (R2= 0,7523.

  13. In vitro activity of kombucha tea ethyl acetate fraction against Malassezia species isolated from seborrhoeic dermatitis.

    Science.gov (United States)

    Mahmoudi, E; Saeidi, M; Marashi, M A; Moafi, A; Mahmoodi, V; Zeinolabedini Zamani, M

    2016-12-01

    Seborrheic dermatitis is a chronic and recurrent superficial dermatitis in which Malassezia species play an important role. There are different Malassezia species, which have been recently reported to be resistant to common antifungals. Natural sources can be useful alternatives to reduce the emergence of this resistance. Kombucha tea is believed to have potential antimicrobial properties. Regarding this, the present study aimed to investigate the antifungal activity of Kombucha tea ethyl acetate fraction (KEAF) against Malassezia species obtained from the patients with seborrheic dermatitis. A total of 23 clinical isolates were identified by direct microscopic examination and Tween assimilation, and then confirmed by DNA sequencing of ITS regions for Malassezia species. Kombucha tea was fractionated using ethyl acetate (1:2 v/v). The minimum inhibitory concentration (MIC) microdilution assay was used to evaluate the anti- Malssezia activity of KEAF at three concentrations of 10, 40, and 80 mg/mL. The results of the DNA sequence analysis indicated that M. furfur (39.13%) was the predominant species, followed by M. globosa (30.43%), M. sloofie (13.04%), M. sympodialis (13.04%), and M. restricta (4.34%), respectively. Furthermore, KEAF showed inhibitory activity against Malassezia species. Accordingly, KEAF had the lowest and highest MIC value against M. sloofie and M. restricta , respectively. Moreover, the inhibitory effect of the extract was equivalent to that of ketoconazole at 4.8 µg/mL. The findings of the current study highlighted the antifungal properties of KEAF. Therefore, this extract can be promoted as complementary medicine for the treatment of the infections caused by Malassezia .

  14. Parallel evolution of TCP and B-class genes in Commelinaceae flower bilateral symmetry

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    Preston Jill C

    2012-03-01

    Full Text Available Abstract Background Flower bilateral symmetry (zygomorphy has evolved multiple times independently across angiosperms and is correlated with increased pollinator specialization and speciation rates. Functional and expression analyses in distantly related core eudicots and monocots implicate independent recruitment of class II TCP genes in the evolution of flower bilateral symmetry. Furthermore, available evidence suggests that monocot flower bilateral symmetry might also have evolved through changes in B-class homeotic MADS-box gene function. Methods In order to test the non-exclusive hypotheses that changes in TCP and B-class gene developmental function underlie flower symmetry evolution in the monocot family Commelinaceae, we compared expression patterns of teosinte branched1 (TB1-like, DEFICIENS (DEF-like, and GLOBOSA (GLO-like genes in morphologically distinct bilaterally symmetrical flowers of Commelina communis and Commelina dianthifolia, and radially symmetrical flowers of Tradescantia pallida. Results Expression data demonstrate that TB1-like genes are asymmetrically expressed in tepals of bilaterally symmetrical Commelina, but not radially symmetrical Tradescantia, flowers. Furthermore, DEF-like genes are expressed in showy inner tepals, staminodes and stamens of all three species, but not in the distinct outer tepal-like ventral inner tepals of C. communis. Conclusions Together with other studies, these data suggest parallel recruitment of TB1-like genes in the independent evolution of flower bilateral symmetry at early stages of Commelina flower development, and the later stage homeotic transformation of C. communis inner tepals into outer tepals through the loss of DEF-like gene expression.

  15. Insect galls from Atlantic Forest areas of Santa Teresa, Espírito Santo, Brazil: characterization and occurrence

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    Valéria Cid Maia

    2014-01-01

    Full Text Available Galhas de insetos de areas de Mata Atlântica de Santa Teresa, Espírito Santo, Brasil: caracterização e ocorrência. Três áreas protegidas de Mata atlântica foram investigadas em  Santa Teresa, Espírito Santo, de junho de 2007 a agosto de 2009: Estação Biológica de Santa Lúcia, Reserva Biológica Augusto Ruschi e Parque Natural Municipal São Lourenço. A vegetação local foi examinada à procura de galhas de insetos. Foram encontrados 265 morfotipos de galhas em 141 espécies de plantas (104 gêneros e 49 famílias. Asteraceae, Fabaceae, Myrtaceae, Melastomataceae e Rubiaceae foram as famílias de planta com maior riqueza de galhas. Os gêneros super-hospedeiros foram Mikania Willd. (Asteraceae, Myrcia DC. ex. Guill. (Myrtaceae e Inga Mill. (Fabaceae. A espécie super-hospedeira foi Guapira opposita (Vell. Reitz. (Nyctaginaceae. As galhas foram encontradas em folhas, caules, botões, raízes e gavinhas. As folhas foram o órgão vegetal mais galhado, seguidas pelos caules e botões. Os indutores pertencem a quatro ordens de insetos: Diptera, Lepidoptera, Hemiptera e Thysanoptera, sendo Cecidomyiidae (Diptera os mais frequentes e diversificados galhadores. Inquilinos foram obtidos de seis morfotipos de galhas, estando representados por Cecidomyiidae and Muscomorpha. Nove species galhadoras são registradas pela primeira vez no Estado do Espírito Santo, e Cordiamyia globosa Maia, 1996 é assinalada pela primeira vez para o município de Santa Teresa. O presente estudo indica Santa Teresa (ES como a área de Mata Atlântica com maior riqueza de galhas de insetos.

  16. Are plants used for skin care in South Africa fully explored?

    Science.gov (United States)

    Lall, Namrita; Kishore, Navneet

    2014-04-11

    capense, Hyaenanche globosa, Harpephyllum caffrum, Ximenia americana, Leucosidea sericea Artemisia afra, and six Aloe species have been scientifically validated by our research group for skin hyperpigmentation problems. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  17. Grazing experiments and model simulations of the role of zooplankton in Phaeocystis food webs

    Science.gov (United States)

    Verity, P. G.

    2000-08-01

    A combined empirical and modelling study was conducted to further examine the potential importance of grazing by zooplankton in pelagic food webs in which Phaeocystis is a significant or dominant component. Laboratory experiments were designed to measure ingestion of Phaeocystis and other potential prey items which co-occur with Phaeocystis. Grazers included copepods and ciliates, and prey included Phaeocystis colonies and solitary cells, diatoms, ciliates, bacteria, and detritus. These data were expressed in the model currency of nitrogen units, and fit to hyperbolic tangent equations which included minimum prey thresholds. These equations and literature data were used to constrain a food web model whose purpose was to investigate trophic interactions rather than to mimic actual events. Nevertheless, the model output was similar to the general pattern and magnitude of development of Phaeocystis-diatom communities in some environments where they occur, e.g. north Norwegian waters. The model included three forms of nitrogen, three phytoplankton groups, bacteria, two zooplankton groups, and detritus, with detailed flows between compartments. An important component of the model was inclusion of variable prey preferences for zooplankton. The experiments and model simulations suggest several salient conclusions. Phaeocystis globosa colonies were eaten by a medium-sized copepod species, but ingestion appeared to be strongly dependent upon a proper size match between grazer and prey. If not, colonies were eaten little if at all. Phaeocystis solitary cells were ingested rapidly by ciliate microzooplankton, in agreement with prior literature observations. In contrast, detritus was eaten comparatively slowly by both ciliates and copepods. Both types of zooplankton exhibited apparent minimum prey thresholds below which grazing did not occur or was inconsequential. Model simulations implied that transitions between life cycle stages of Phaeocystis may potentially be important

  18. Vegetation description of the Doornhoek section of the Mountain Zebra National Park (MZNP, South Africa

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    Hugo Bezuidenhout

    2008-12-01

    Full Text Available The Mountain Zebra National Park (MZNP has been extended over the last couple of years. One of the newly procured areas is the Doornhoek section, which had been adjacent to the park. To develop scientifically sound management programmes for conservation areas, it is essential that an inventory of their natural resources be undertaken. The aim of this study was to classify, describe and map the vegetation of the Doornhoek section of the park. The floristic data were analysed in accordance with the Braun-Blanquet procedures using the BBPC suite. The data analysis resulted in the identification of eight communities, which can be grouped into seven major community types (Rhus lucida–Buddleja glomerata Shrubland, Rhigozum obovatum–Rhus longispina Shrubland, Helichrysum dregeanum–Aristida diffusa Grassland, Pentzia globosa–Enneapogon scoparius Grassland, Aristida adscensionus–Pentzia globosa Grassland, Cadaba aphylla–Acacia karroo Woodland and Lycium oxycarpum–Acacia karroo Woodland. Four of these communities occur on the higher-lying plateau, mid-slope and crest areas, while the other four communities are located on the lower-lying mid-plateau and foot slope, along drainage lines and in valley-bottom areas. The description of the plant communities, together with the vegetation map, can serve as a basis for formulating a management programme for the larger park. Although sections of Doornhoek have been overgrazed and degraded in the past, its recent addition to the MZNP contributes to the available habitat preferred by large herbivores, such as valley bottoms, foot-slopes and plateaux.

  19. Morphological "primary homology" and expression of AG-subfamily MADS-box genes in pines, podocarps, and yews.

    Science.gov (United States)

    Englund, Marie; Carlsbecker, Annelie; Engström, Peter; Vergara-Silva, Francisco

    2011-01-01

    The morphological variation among reproductive organs of extant gymnosperms is remarkable, especially among conifers. Several hypotheses concerning morphological homology between various conifer reproductive organs have been put forward, in particular in relation to the pine ovuliferous scale. Here, we use the expression patterns of orthologs of the ABC-model MADS-box gene AGAMOUS (AG) for testing morphological homology hypotheses related to organs of the conifer female cone. To this end, we first developed a tailored 3'RACE procedure that allows reliable amplification of partial sequences highly similar to gymnosperm-derived members of the AG-subfamily of MADS-box genes. Expression patterns of two novel conifer AG orthologs cloned with this procedure-namely PodAG and TgAG, obtained from the podocarp Podocarpus reichei and the yew Taxus globosa, respectively-are then further characterized in the morphologically divergent female cones of these species. The expression patterns of PodAG and TgAG are compared with those of DAL2, a previously discovered Picea abies (Pinaceae) AG ortholog. By treating the expression patterns of DAL2, PodAG, and TgAG as character states mapped onto currently accepted cladogram topologies, we suggest that the epimatium-that is, the podocarp female cone organ previously postulated as a "modified" ovuliferous scale-and the canonical Pinaceae ovuliferous scale can be legitimally conceptualized as "primary homologs." Character state mapping for TgAG suggests in turn that the aril of Taxaceae should be considered as a different type of organ. This work demonstrates how the interaction between developmental-genetic data and formal cladistic theory could fruitfully contribute to gymnosperm systematics. © 2011 Wiley Periodicals, Inc.

  20. An ethnobotanical survey of medicinal plants in Trinidad.

    Science.gov (United States)

    Clement, Y N; Baksh-Comeau, Y S; Seaforth, C E

    2015-09-15

    An ethnobotanical survey was conducted on the Caribbean island of Trinidad to identify medicinal plants commonly used in traditional medicine to treat a variety of medical conditions. A pilot survey was conducted to identify the top ten most common ailments where medicinal plants were used. The results of the foregoing study guided a wider national survey conducted between October 2007 and July 2008. A total of 450 households from 50 rural communities were interviewed using the TRAMIL (Traditional Medicine in the Islands) questionnaire for data collection. Details of plants, part(s) used, and remedy formulations were elicited from informants and voucher specimens collected for identification at the National Herbarium of Trinidad and Tobago. The TRAMIL methodology set a limit of a plant with 20 % or more citations for any particular ailment as having significant or popular use. At the end of the survey 917 single plant remedies were identified. The majority of species were from the following families; Asteraceae, Lamiaceae, Leguminosae, Verbenaceae and Poaceae. Applying the TRAMIL 20 % citation of a plant for popular use as significant, Leonotis nepetifolia (for cough/common cold), Gomphrena globosa (for "stoppage-of-water"), Curcuma longa and Senna occidentalis (for "afterbirth"), Cymbopogon citratus and Neurolaena lobata (for fever), and Citrus limon (for kidney stones) qualified in our study. Those not reaching the TRAMIL 20 % significant (popular) use were Stachytarpheta jamaicensis (L.) Vahl, Senna alata (L.) Roxb.and Momordica charantia L. which were widely used as "'cooling/cleanser'" in our survey. Our survey showed significant retention of traditional knowledge of medicinal plants in rural Trinidad. More interestingly, a large remnant of medico-cultural concepts such as "cooling/cleanser", "afterbirth", "stoppage-of-water" and "womb infection" persist in the rural population. Although the scientific literature show that some of the cited plants possessed

  1. Export of a Winter Shelf Phytoplankton Bloom at the Shelf Margin of Long Bay (South Atlantic Bight, USA)

    Science.gov (United States)

    Nelson, J.; Seim, H.; Edwards, C. R.; Lockhart, S.; Moore, T.; Robertson, C. Y.; Amft, J.

    2016-02-01

    A winter 2012 field study off Long Bay (seaward of Myrtle Beach, South Carolina) investigated exchange processes along the shelf margin. Topics addressed included mechanisms of nutrient input (upper slope to outer shelf), phytoplankton blooms and community characteristics (mid-to-outer shelf), and possible export of shelf bloom material (transport to and across the shelf break to the upper slope). Observations utilized three moorings (mid-shelf, shelf break, upper slope), two gliders and ship operations (repeat cruises with profiling, water sampling and towed body surveys) along with satellite SST and ocean color imagery and near-by NOAA buoy records. Here we focus on the late January to early February period, when a mid-shelf bloom of Phaeocystis globosa (which forms large gelatinous colonies) was transported to the shelf break. The presence of Phaeocystis colonies resulted in strong spiking in chlorophyll (chl) fluorescence profiles. A partitioning approach was adapted to estimate chl in colonies (spikes) and small forms (baseline signal) and to account for an apparent difference in measured in vivo fluorescence per unit chl (lower in colonies). Up to 40-50% of chl in the bloom (surface to bottom on the mid-shelf) was estimated to be in the colonies. In late January, there a pronounced seaward slumping of relatively dense mid-shelf water along the bottom under warmer surface water derived from the inshore edge of a broad jet of Gulf Stream water flowing southwestward along the upper slope. We describe the evolution of this event and the conditions which set up this mechanism for episodic near-bed transport of fresh bloom material produced on the shelf to the upper slope off Long Bay. Down-slope transport may have been enhanced in this case by the high phytoplankton biomass in gelatinous colonies, which appeared to be settling in the water column on the shelf prior to the transport event.

  2. Efficacy of medicinal essential oils against pathogenic Malassezia sp. isolates.

    Science.gov (United States)

    Khosravi, A R; Shokri, H; Fahimirad, S

    2016-03-01

    The purposes of this study were to evaluate the distribution pattern and population size of Malassezia species in dogs with atopic dermatitis (AD) and the inhibitory efficacy of Zataria multiflora, Thymus kotschyanus, Mentha spicata, Artemisia sieberi, Rosmarinus officinalis and Heracleum persicum essential oils against pathogenic Malassezia isolates. The samples were collected from 5 different anatomical sites of 33 atopic dogs and cultured onto modified Dixon agar (MDA) and Sabouraud dextrose agar (SDA) media. The essential oil extraction was performed by steam distillation using Clevenger system. Anti-Malassezia efficacy of medicinal essential oils and standard drugs was evaluated using broth microdilution method. A total of 103 yeast colonies were isolated from dogs with AD. Eight different Malassezia species were identified as follows: Malassezia pachydermatis (81.4%), M. globosa (7.8%), M. restricta (3.9%), M. sloofiae (2.9%), M. furfur (1%), M. nana (1%), M. obtusa (1%) and M. sympodialis (1%). The most and least infected sites were: anal (21.2%) and ear (10.6%) respectively. M. pachydermatis was the most frequent Malassezia species isolated from both skin and mucosa of dogs with AD. Antifungal susceptibility test revealed the inhibitory efficacy of essential oils on pathogenic Malassezia isolates with minimum inhibitory concentration (MIC(90)) values ranging from 30 to 850 μg/mL. Among the tested oils, Z. multiflora and T. kotschyanus exhibited the highest inhibitory effects (Pessential oils of Z. multiflora and T. kotschyanus showed strong antifungal activity against pathogenic Malassezia species tested. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  3. Caracterização morfológica de frutos, sementes e germinação de Sideroxylon obtusifolium (Roem. e Schult. Penn. (Sapotaceae

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    Kelina Bernardo Silva

    2012-02-01

    Full Text Available Estudos que visam ao conhecimento da morfologia de sementes e plântulas contribuem para a identificação das espécies, facilitando o reconhecimento das fases iniciais do seu desenvolvimento. Assim, os objetivos deste trabalho foram caracterizar morfologicamente as estruturas externa e interna dos frutos e das sementes de Sideroxylon obtusifolium (Roem. e Schult. Penn., além de descrever e ilustrar a morfologia externa da plântula. Para a descrição dos frutos foram observados detalhes externos e internos do pericarpo, referentes a textura, consistência, cor, pilosidade, brilho, forma, número de sementes por fruto e deiscência. Foram analisadas as seguintes variáveis externas das sementes: dimensões, cor, textura, consistência, forma e posição do hilo e da micrópila; e as internas: presença ou ausência de endosperma, tipo, forma, cor, posição dos cotilédones, eixo-hipocótilo-radícula e plúmula. A germinação foi considerada desde o intumescimento da semente até a emissão dos protófilos, sendo a plântula considerada estabelecida quando os protófilos já estavam totalmente expandidos. Os frutos de S. obtusifolium são dos tipos bacoide, globoso ou elipsoide, indeiscente e monospérmico. As sementes variam de globosas a elipsoides, e o embrião é do tipo cotiledonar e ocupa posição basal na semente. A germinação tem início no décimo segundo dia e pode ser encerrada no vigésimo primeiro dia após a semeadura.

  4. Rapid identification of emerging human-pathogenic Sporothrix species with rolling circle amplification

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    Anderson Messias Rodrigues

    2015-12-01

    Full Text Available Sporothrix infections are emerging as an important human and animal threat among otherwise healthy patients, especially in Brazil and China. Correct identification of sporotrichosis agents is beneficial for epidemiological surveillance, enabling implementation of adequate public-health policies and guiding antifungal therapy. In areas of limited resources where sporotrichosis is endemic, high-throughput detection methods that are specific and sensitive are preferred over phenotypic methods that usually result in misidentification of closely related Sporothrix species. We sought to establish rolling circle amplification (RCA as a low-cost screening tool for species-specific identification of human-pathogenic Sporothrix. We developed six species-specific padlock probes targeting polymorphisms in the gene encoding calmodulin. BLAST-searches revealed candidate probes that were conserved intraspecifically; no significant homology with sequences from humans, mice, plants or microorganisms outside members of Sporothrix were found. The accuracy of our RCA-based assay was demonstrated through the specificity of probe-template binding to 25 S. brasiliensis, 58 S. schenckii, 5 S. globosa, 1 S. luriei, 4 S. mexicana, and 3 S. pallida samples. No cross reactivity between closely related species was evident in vitro, and padlock probes yielded 100% specificity and sensitivity down to 3 x 10 6 copies of the target sequence. RCA-based speciation matched identifications via phylogenetic analysis of the gene encoding calmodulin and the rDNA operon (kappa 1.0; 95% confidence interval 1.0-1.0, supporting its use as a reliable alternative to DNA sequencing. This method is a powerful tool for rapid identification and specific detection of medically relevant Sporothrix, and due to its robustness has potential for ecological studies.

  5. Swarming and complex pattern formation in Paenibacillus vortex studied by imaging and tracking cells

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    Jacob Eshel

    2008-02-01

    Full Text Available Abstract Background Swarming motility allows microorganisms to move rapidly over surfaces. The Gram-positive bacterium Paenibacillus vortex exhibits advanced cooperative motility on agar plates resulting in intricate colonial patterns with geometries that are highly sensitive to the environment. The cellular mechanisms that underpin the complex multicellular organization of such a simple organism are not well understood. Results Swarming by P. vortex was studied by real-time light microscopy, by in situ scanning electron microscopy and by tracking the spread of antibiotic-resistant cells within antibiotic-sensitive colonies. When swarming, P. vortex was found to be peritrichously flagellated. Swarming by the curved cells of P. vortex occurred on an extremely wide range of media and agar concentrations (0.3 to 2.2% w/v. At high agar concentrations (> 1% w/v rotating colonies formed that could be detached from the main mass of cells by withdrawal of cells into the latter. On lower percentage agars, cells moved in an extended network composed of interconnected "snakes" with short-term collision avoidance and sensitivity to extracts from swarming cells. P. vortex formed single Petri dish-wide "supercolonies" with a colony-wide exchange of motile cells. Swarming cells were coupled by rapidly forming, reversible and non-rigid connections to form a loose raft, apparently connected via flagella. Inhibitors of swarming (p-Nitrophenylglycerol and Congo Red were identified. Mitomycin C was used to trigger filamentation without inhibiting growth or swarming; this facilitated dissection of the detail of swarming. Mitomycin C treatment resulted in malcoordinated swarming and abortive side branch formation and a strong tendency by a subpopulation of the cells to form minimal rotating aggregates of only a few cells. Conclusion P. vortex creates complex macroscopic colonies within which there is considerable reflux and movement and interaction of cells. Cell

  6. Lactobacillus ruminis strains cluster according to their mammalian gut source.

    Science.gov (United States)

    O' Donnell, Michelle M; Harris, Hugh Michael B; Lynch, Denise B; Ross, Reynolds Paul; O'Toole, Paul W

    2015-04-01

    Lactobacillus ruminis is a motile Lactobacillus that is autochthonous to the human gut, and which may also be isolated from other mammals. Detailed characterization of L. ruminis has previously been restricted to strains of human and bovine origin. We therefore sought to expand our bio-bank of strains to identify and characterise isolates of porcine and equine origin by comparative genomics. We isolated five strains from the faeces of horses and two strains from pigs, and compared their motility, biochemistry and genetic relatedness to six human isolates and three bovine isolates including the type strain 27780(T). Multilocus sequence typing analysis based on concatenated sequence data for six individual loci separated the 16 L. ruminis strains into three clades concordant with human, bovine or porcine, and equine sources. Sequencing the genomes of four additional strains of human, bovine, equine and porcine origin revealed a high level of genome synteny, independent of the source animal. Analysis of carbohydrate utilization, stress survival and technological robustness in a combined panel of sixteen L. ruminis isolates identified strains with optimal survival characteristics suitable for future investigation as candidate probiotics. Under laboratory conditions, six human isolates of L. ruminis tested were aflagellate and non-motile, whereas all 10 strains of bovine, equine and porcine origin were motile. Interestingly the equine and porcine strains were hyper-flagellated compared to bovine isolates, and this hyper-flagellate phenotype correlated with the ability to swarm on solid medium containing up to 1.8% agar. Analysis by RNA sequencing and qRT-PCR identified genes for the biosynthesis of flagella, genes for carbohydrate metabolism and genes of unknown function that were differentially expressed in swarming cells of an equine isolate of L. ruminis. We suggest that Lactobacillus ruminis isolates have potential to be used in the functional food industry. We

  7. Assessing Drivers of Coastal Primary Production in Northern Marguerite Bay, Antarctica

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    Patrick D. Rozema

    2017-06-01

    Full Text Available The coastal ocean of the climatically-sensitive west Antarctic Peninsula is experiencing changes in the physical and (photochemical properties that strongly affect the phytoplankton. Consequently, a shift from diatoms, pivotal in the Antarctic food web, to more mobile and smaller flagellates has been observed. We seek to identify the main drivers behind primary production (PP without any assumptions beforehand to obtain the best possible model of PP. We employed a combination of field measurements and modeling to discern and quantify the influences of variability in physical, (photochemical, and biological parameters on PP in northern Marguerite Bay. Field data of high-temporal resolution (November 2013–March 2014 collected at a long-term monitoring site here were combined with estimates of PP derived from photosynthesis-irradiance incubations and modeled using mechanistic and statistical models. Daily PP varied greatly and averaged 1,764 mg C m−2 d−1 with a maximum of 6,908 mg C m−2 d−1 after the melting of sea ice and the likely release of diatoms concentrated therein. A non-assumptive random forest model (RF with all possibly relevant parameters (MRFmax showed that variability in PP was best explained by light availability and chlorophyll a followed by physical (temperature, mixed layer depth, and salinity and chemical (phosphate, total nitrogen, and silicate water column properties. The predictive power from the relative abundances of diatoms, cryptophytes, and haptophytes (as determined by pigment fingerprinting to PP was minimal. However, the variability in PP due to changes in species composition was most likely underestimated due to the contrasting strategies of these phytoplankton groups as we observed significant negative relations between PP and the relative abundance of flagellates groups. Our reduced model (MRFmin showed how light availability, chlorophyll a, and total nitrogen concentrations can be used to obtain the best

  8. The metabolic response of marine copepods to environmental warming and ocean acidification in the absence of food

    Science.gov (United States)

    Mayor, Daniel J.; Sommer, Ulf; Cook, Kathryn B.; Viant, Mark R.

    2015-09-01

    Marine copepods are central to the productivity and biogeochemistry of marine ecosystems. Nevertheless, the direct and indirect effects of climate change on their metabolic functioning remain poorly understood. Here, we use metabolomics, the unbiased study of multiple low molecular weight organic metabolites, to examine how the physiology of Calanus spp. is affected by end-of-century global warming and ocean acidification scenarios. We report that the physiological stresses associated with incubation without food over a 5-day period greatly exceed those caused directly by seawater temperature or pH perturbations. This highlights the need to contextualise the results of climate change experiments by comparison to other, naturally occurring stressors such as food deprivation, which is being exacerbated by global warming. Protein and lipid metabolism were up-regulated in the food-deprived animals, with a novel class of taurine-containing lipids and the essential polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid and docosahexaenoic acid, changing significantly over the duration of our experiment. Copepods derive these PUFAs by ingesting diatoms and flagellated microplankton respectively. Climate-driven changes in the productivity, phenology and composition of microplankton communities, and hence the availability of these fatty acids, therefore have the potential to influence the ability of copepods to survive starvation and other environmental stressors.

  9. Proximity Interactions among Basal Body Components in Trypanosoma brucei Identify Novel Regulators of Basal Body Biogenesis and Inheritance

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    Hung Quang Dang

    2017-01-01

    Full Text Available The basal body shares similar architecture with centrioles in animals and is involved in nucleating flagellar axonemal microtubules in flagellated eukaryotes. The early-branching Trypanosoma brucei possesses a motile flagellum nucleated from the basal body that consists of a mature basal body and an adjacent pro-basal body. Little is known about the basal body proteome and its roles in basal body biogenesis and flagellar axoneme assembly in T. brucei. Here, we report the identification of 14 conserved centriole/basal body protein homologs and 25 trypanosome-specific basal body proteins. These proteins localize to distinct subdomains of the basal body, and several of them form a ring-like structure surrounding the basal body barrel. Functional characterization of representative basal body proteins revealed distinct roles in basal body duplication/separation and flagellar axoneme assembly. Overall, this work identified novel proteins required for basal body duplication and separation and uncovered new functions of conserved basal body proteins in basal body duplication and separation, highlighting an unusual mechanism of basal body biogenesis and inheritance in this early divergent eukaryote.

  10. "Ormilo disease" a disorder of zebu cattle in Tanzania: bovine cerebral theileriosis or new protozoan disease?

    Science.gov (United States)

    Catalano, Deborah; Biasibetti, Elena; Lynen, Godelieve; Di Giulio, Giuseppe; De Meneghi, Daniele; Tomassone, Laura; Valenza, Federico; Capucchio, Maria Teresa

    2015-06-01

    "Ormilo" disease is a neurological disorder of cattle described by Maasai herders in Tanzania. It is attributed to infection by Theileria species, although no detailed data are available in the literature. The authors describe the macroscopical and histological changes observed in 30 brains of indigenous short-horn zebu cattle from Northern Tanzania, aged 2-9 years, with the characteristic neurological signs of "Ormilo". Moreover, the ultrastructural details observed in 14 selected brain samples were reported. Areas of congestion and hemorrhages, associated with the obstruction of the cerebral vessels with large numbers of parasitized lymphoid cells, were observed. Electron microscopy showed the presence of intralymphocytic parasites morphologically comparable to flagellated protozoa, not previously described in the lymphoid cells of cattle, but only reported during the sexual stages within the vector. Theileria taurotragi was detected by polymerase chain reaction (PCR) and reverse line blot (RLB) in nine samples. The authors hypothesize that the parasite detected by electron microscopy could be a strain of a Theileria endemic to this region till now not investigated, having an intralymphocytic phase and being associated with other Theileria spp. infestation. Further studies are needed to better understand the etiology of "Ormilo" disease and to characterize the morphology of the observed parasite, clarifying its role in the disease in Tanzania.

  11. Ciguatera fish poisoning: a first epidemic in Germany highlights an increasing risk for European countries.

    Science.gov (United States)

    Mattei, César; Vetter, Irina; Eisenblätter, Anneka; Krock, Bernd; Ebbecke, Martin; Desel, Herbert; Zimmermann, Katharina

    2014-12-01

    Toxin-producing microalgae are thriving worldwide due to coral reef destruction and global warming with major consequences on ecosystems, international trade and human health. Microalgae belonging to the family of flagellate protists, in particular dinoflagellates, secrete a variety of high-molecular-weight polyether toxins that accumulate through the marine food chain to cause disease in humans by acting as sodium channel activator toxins; ciguatera is the most frequent seafood-borne illness worldwide with 50,000 to 500,000 global incidences per annum and is usually limited to endemic areas located between 35° northern and 35° southern latitude. The rising global incidence frequency renders it a major human health problem, because no curative treatment is available yet and reliable detection assays are lacking. During the last decade ciguatera has increasingly become endemic in previously unaffected areas for two reasons: first global warming has contributed to the emergence of dinoflagellate species in subtropical and even temperate regions that previously had been constrained to tropical areas and second: in Europe globalization of fishing industry and tourism has led to a progressive increase in the number of ciguatera cases and a lack of awareness among medical personnel contributes to under-reporting. We review, through a recent ciguatera outbreak in Germany, the risk for ciguatera poisoning in Europe and highlight characteristic symptoms, current knowledge about disease pathomechanisms and treatment options.

  12. Há 100 anos, a descoberta do Treponema pallidum A hundred years ago, the discovery of Treponema pallidum

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    Elemir Macedo de Souza

    2005-10-01

    Full Text Available A descoberta do Treponema pallidum por Schaudinn & Hoffmann em 3 de março de 1905 foi influenciada pela comunicação de Siegel, sobre a descoberta do agente etiológico da sífilis. Encarada com ceticismo, a comunicação acarretou novas investigações, conduzidas pelo zoologista Schaudinn e pelo dermatologista Hoffmann -primeiros observadores do agente da sífilis, denominado Spirochaeta pallida. A descoberta foi o passo inicial para o desenvolvimento dos procedimentos diagnósticos e terapêuticos nos anos subseqüentes.The discovery of Treponema pallidum by Schaudinn & Hoffmann, on March 3rd 1905, was influenced by Siegels' communication on the finding of the etiological agent of syphilis. John Siegel, working at the Institut of Zoology, University of Berlin, claimed to have found a flagellate protozoon in syphilitic lesions. Because of the skepticism it was received with, this communcation yielded further investigation, conducted by zoologist Schaudinn and dermatologist Hoffmann. They were the first investigators to find the etiological agent of syphilis, described under the name of Spirochaeta pallida. The discovery of Treponema pallidum on March 3rd 1905 was the first step towards the development of diagnostic and therapeutic procedures in subsequent years.

  13. Protein preparation, crystallization and preliminary X-ray analysis of Trypanosoma cruzi nucleoside diphosphate kinase 1

    International Nuclear Information System (INIS)

    Gómez Barroso, J. A.; Pereira, H.; Miranda, M.; Pereira, C.; Garratt, R. C.; Aguilar, C. F.

    2010-01-01

    T. cruzi TcNDPK1 was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. The flagellated protozoan parasite Trypanosoma cruzi is the aetiological agent of Chagas disease. Nucleoside diphosphate kinases (NDPKs) are enzymes that are involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform, was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. Crystals grew after 72 h in 0.2 M MgCl 2 , 20% PEG 3350. Data were collected to 3.5 Å resolution using synchrotron X-ray radiation at the National Synchrotron Light Laboratory (Campinas, Brazil). The crystals belonged to the trigonal space group P3, with unit-cell parameters a = b = 127.84, c = 275.49 Å. Structure determination is under way and will provide relevant information that may lead to the first step in rational drug design for the treatment of Chagas disease

  14. Ribosomal RNA analysis indicates a benthic pennate diatom ancestry for the endosymbionts of the dinoflagellates Peridinium foliaceum and Peridinium balticum (Pyrrhophyta).

    Science.gov (United States)

    Chesnick, J M; Kooistra, W H; Wellbrock, U; Medlin, L K

    1997-01-01

    The establishment of chloroplasts as cellular organelles in the dinoflagellate, heterokont (stramenopile), haptophyte, and cryptophyte algae is widely accepted to have been the result of secondary endosymbiotic events, that is, the uptake of a photosynthetic eukaryote by a phagotrophic eukaryote. However, the circumstances that promote such associations between two phylogenetically distinct organisms and result in the integration of their genomes to form a single functional photosynthetic cell is unclear. The dinoflagellates Peridinium foliaceum and Peridinium balticum are unusual in that each contains a membrane-bound eukaryotic heterokont endosymbiont. These symbioses have been interpreted, through data derived from ultrastructural and biochemical investigations, to represent an intermediate stage of secondary endosymbiotic chloroplast acquisition. In this study we have examined the phylogenetic origin of the P. foliaceum and P. balticum heterokont endosymbionts through analysis of their nuclear small subunit ribosomal RNA genes. Our analyses clearly demonstrate both endosymbionts are pennate diatoms belonging to the family Bacillariaceae. Since members of the Bacillariaceae are usually benthic, living on shallow marine sediments, the manner in which establishment of a symbiosis between a planktonic flagellated dinoflagellate and a bottom-dwelling diatom is discussed. In particular, specific environmentally-associated life strategy stages of the host and symbiont, coupled with diatom food preferences by the dinoflagellate, may have been vital to the formation of this association.

  15. The crystal structure of Giardia duodenalis 14-3-3 in the apo form: when protein post-translational modifications make the difference.

    KAUST Repository

    Fiorillo, Annarita

    2014-03-21

    The 14-3-3s are a family of dimeric evolutionary conserved pSer/pThr binding proteins that play a key role in multiple biological processes by interacting with a plethora of client proteins. Giardia duodenalis is a flagellated protozoan that affects millions of people worldwide causing an acute and chronic diarrheal disease. The single giardial 14-3-3 isoform (g14-3-3), unique in the 14-3-3 family, needs the constitutive phosphorylation of Thr214 and the polyglycylation of its C-terminus to be fully functional in vivo. Alteration of the phosphorylation and polyglycylation status affects the parasite differentiation into the cyst stage. To further investigate the role of these post-translational modifications, the crystal structure of the g14-3-3 was solved in the unmodified apo form. Oligomers of g14-3-3 were observed due to domain swapping events at the protein C-terminus. The formation of filaments was supported by TEM. Mutational analysis, in combination with native PAGE and chemical cross-linking, proved that polyglycylation prevents oligomerization. In silico phosphorylation and molecular dynamics simulations supported a structural role for the phosphorylation of Thr214 in promoting target binding. Our findings highlight unique structural features of g14-3-3 opening novel perspectives on the evolutionary history of this protein family and envisaging the possibility to develop anti-giardial drugs targeting g14-3-3.

  16. What if the Diatoms of the Deep Chlorophyll Maximum Can Ascend?

    Science.gov (United States)

    Villareal, T. A.

    2016-02-01

    Buoyancy regulation is an integral part of diatom ecology via its role in sinking rates and is fundamental to understanding their distribution and abundance. Numerous studies have documented the effects of size and nutrition on sinking rates. Many pelagic diatoms have low intrinsic sinking rates when healthy and nutrient-replete (deep chlorophyll maximum. The potential for ascending behavior adds an additional layer of complexity by allowing both active depth regulation similar to that observed in flagellated taxa and upward transport by some fraction of deep euphotic zone diatom blooms supported by nutrient injection. In this talk, I review the data documenting positive buoyancy in small diatoms, offer direct visual evidence of ascending behavior in common diatoms typical of both oceanic and coastal zones, and note the characteristics of sinking rate distributions within a single species. Buoyancy control leads to bidirectional movement at similar rates across a wide size spectrum of diatoms although the frequency of ascending behavior may be only a small portion of the individual species' abundance. While much remains to be learned, the paradigm of unidirectional downward movement by diatoms is both inaccurate and an oversimplification.

  17. Evaluation of Zosteric Acid for Mitigating Biofilm Formation of Pseudomonas putida Isolated from a Membrane Bioreactor System

    Directory of Open Access Journals (Sweden)

    Andrea Polo

    2014-05-01

    Full Text Available This study provides data to define an efficient biocide-free strategy based on zosteric acid to counteract biofilm formation on the membranes of submerged bioreactor system plants. 16S rRNA gene phylogenetic analysis showed that gammaproteobacteria was the prevalent taxa on fouled membranes of an Italian wastewater plant. Pseudomonas was the prevalent genus among the cultivable membrane-fouler bacteria and Pseudomonas putida was selected as the target microorganism to test the efficacy of the antifoulant. Zosteric acid was not a source of carbon and energy for P. putida cells and, at 200 mg/L, it caused a reduction of bacterial coverage by 80%. Biofilm experiments confirmed the compound caused a significant decrease in biomass (−97% and thickness (−50%, and it induced a migration activity of the peritrichous flagellated P. putida over the polycarbonate surface not amenable to a biofilm phenotype. The low octanol-water partitioning coefficient and the high water solubility suggested a low bioaccumulation potential and the water compartment as its main environmental recipient and capacitor. Preliminary ecotoxicological tests did not highlight direct toxicity effects toward Daphnia magna. For green algae Pseudokirchneriella subcapitata an effect was observed at concentrations above 100 mg/L with a significant growth of protozoa that may be connected to a concurrent algal growth inhibition.

  18. Mechanisms of growth inhibition of Phytomonas serpens by the alkaloids tomatine and tomatidine

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    Jorge Mansur Medina

    2015-02-01

    Full Text Available Phytomonas serpens are flagellates in the family Trypanosomatidae that parasitise the tomato plant (Solanum lycopersicum L., which results in fruits with low commercial value. The tomato glycoalkaloid tomatine and its aglycone tomatidine inhibit the growth of P. serpens in axenic cultures. Tomatine, like many other saponins, induces permeabilisation of the cell membrane and a loss of cell content, including the cytosolic enzyme pyruvate kinase. In contrast, tomatidine does not cause permeabilisation of membranes, but instead provokes morphological changes, including vacuolisation. Phytomonas treated with tomatidine show an increased accumulation of labelled neutral lipids (BODYPY-palmitic, a notable decrease in the amount of C24-alkylated sterols and an increase in zymosterol content. These results are consistent with the inhibition of 24-sterol methyltransferase (SMT, which is an important enzyme that is responsible for the methylation of sterols at the 24 position. We propose that the main target of tomatidine is the sterols biosynthetic pathway, specifically, inhibition of the 24-SMT. Altogether, the results obtained in the present paper suggest a more general effect of alkaloids in trypanosomatids, which opens potential therapeutic possibilities for the treatment of the diseases caused by these pathogens.

  19. Serological survey for Leishmania sp. infection in wild animals from the municipality of Maringá, Paraná state, Brazil

    Directory of Open Access Journals (Sweden)

    EM Voltarelli

    2009-01-01

    Full Text Available Leishmania sp. infection was investigated in wild animals from the Ingá Park, in the municipality of Maringá, Paraná state, Brazil, where American cutaneous leishmaniasis (ACL is an endemic disease. Sixty-five mammals, comprising Didelphis albiventris, Cerdocyon thous, Lycalopex vetulus, Cebus apella, Dasyprocta azarae, Dasypus novemcinctus, Procyon cancrivorus and Nasua nasua, were captured. Blood samples were collected for parasite cultivation. Antibodies were investigated by direct agglutination test (DAT using Leishmania (Viannia braziliensis as antigen. Flagellates were observed in blood cultures of 14 (35.9% Didelphis albiventris. Anti-Leishmania antibodies were detected in 31 (51.6% specimens of Cerdocyon thous, Lycalopex vetulus, Cebus apella, Dasyprocta azarae, Procyon cancrivorus and Nasua nasua. These results suggest that Cerdocyon thous and Lycalopex vetulus (crab-eating fox, Cebus apella (capuchin monkey, Dasyprocta azarae (agouti, Procyon cancrivorus (crab-eating raccoon and Nasua nasua (coati play an important role in the ACL transmission cycle in the northwestern region of Paraná, Brazil.

  20. Visualization of Twitching Motility and Characterization of the Role of the PilG in Xylella fastidiosa.

    Science.gov (United States)

    Shi, Xiangyang; Lin, Hong

    2016-04-08

    Xylella fastidiosa is a Gram-negative non-flagellated bacterium that causes a number of economically important diseases of plants. The twitching motility provides X. fastidiosa a means for long-distance intra-plant movement and colonization, contributing toward pathogenicity in X. fastidiosa. The twitching motility of X. fastidiosa is operated by type IV pili. Type IV pili of Xylella fastidiosa are regulated by pilG, a chemotaxis regulator in Pil-Chp operon encoding proteins that are involved with signal transduction pathways. To elucidate the roles of pilG in the twitching motility of X. fastidiosa, a pilG-deficient mutant XfΔpilG and its complementary strain XfΔpilG-C containing native pilG were developed. A microfluidic chambers integrated with a time-lapse image recording system was used to observe twitching motility in XfΔpilG, XfΔpilG-C and its wild type strain. Using this recording system, it permits long-term spatial and temporal observations of aggregation, migration of individual cells and populations of bacteria via twitching motility. X. fastidiosa wild type and complementary XfΔpilG-C strain showed typical twitching motility characteristics directly observed in the microfluidic flow chambers, whereas mutant XfΔpliG exhibited the twitching deficient phenotype. This study demonstrates that pilG contributes to the twitching motility of X. fastidiosa. The microfluidic flow chamber is used as a means for observing twitching motility.

  1. [Dog (Canis familiaris) infectivity to Lutzomyia youngi in Trujillo, Venezuela].

    Science.gov (United States)

    Hernández, Dalila; Rojas, Elina; Scorza, José Vicente; Jorquera, Alicia

    2006-10-01

    In Trujillo, Venezuela the prevalence for American tegumentary leishmaniasis (ATL) is 38 per 100,000 inhabitants. In a periurban, rural settlement of the capital city Trujillo, we studied the potential capability of the domestic dog (Canis familiaris) as a source of infection for Lutzomyia youngi, a phlebotomine sand fly species abundant in the study area and whose domestic vectorial activity has been proven. Dogs with dermal lesions suggestive of ATL and parasitological confirmation of infection, were selected for xenodiagnosis by allowing sylvatic phlebotomines from a ATL free area, to feed ad libitum over each animal's entire body surface. The insects' intestinal tracts were dissected 5 days after the blood meal in order to look for flagellate forms. When these were found, parasitological identification was performed by the multiplex-PCR technique. Four hundred and fifty five sand flies engorged over two dogs in three different assays; promastigotes were found in 4 (0.88%) of the specimens on only one occasion. PCR identified DNA of the Leishmania Viannia subgenus. The household dog has the potential of being a domestic risk factor in the ATL transmission cycle.

  2. The Sensor Kinase GacS Negatively Regulates Flagellar Formation and Motility in a Biocontrol Bacterium, Pseudomonas chlororaphis O6

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    Ji Soo Kim

    2014-06-01

    Full Text Available The GacS/GacA two component system regulates various traits related to the biocontrol potential of plant-associated pseudomonads. The role of the sensor kinase, GacS, differs between strains in regulation of motility. In this study, we determined how a gacS mutation changed cell morphology and motility in Pseudomonas chlororaphis O6. The gacS mutant cells were elongated in stationary-phase compared to the wild type and the complemented gacS mutant, but cells did not differ in length in logarithmic phase. The gacS mutant had a two-fold increase in the number of flagella compared with the wild type strain; flagella number was restored to that of the wild type in the complemented gacS mutant. The more highly flagellated gacS mutant cells had greater swimming motilities than that of the wild type strain. Enhanced flagella formation in the gacS mutant correlated with increased expression of three genes, fleQ, fliQ and flhF, involved in flagellar formation. Expression of these genes in the complemented gacS mutant was similar to that of the wild type. These findings show that this root-colonizing pseudomonad adjusts flagella formation and cell morphology in stationary-phase using GacS as a major regulator.

  3. The Phanerozoic diversification of silica-cycling testate amoebae and its possible links to changes in terrestrial ecosystems

    Science.gov (United States)

    Bosak, Tanja; Lara, Enrique; Mitchell, Edward A.D.

    2015-01-01

    The terrestrial cycling of Si is thought to have a large influence on the terrestrial and marine primary production, as well as the coupled biogeochemical cycles of Si and C. Biomineralization of silica is widespread among terrestrial eukaryotes such as plants, soil diatoms, freshwater sponges, silicifying flagellates and testate amoebae. Two major groups of testate (shelled) amoebae, arcellinids and euglyphids, produce their own silica particles to construct shells. The two are unrelated phylogenetically and acquired biomineralizing capabilities independently. Hyalosphenids, a group within arcellinids, are predators of euglyphids. We demonstrate that hyalosphenids can construct shells using silica scales mineralized by the euglyphids. Parsimony analyses of the current hyalosphenid phylogeny indicate that the ability to “steal” euglyphid scales is most likely ancestral in hyalosphenids, implying that euglyphids should be older than hyalosphenids. However, exactly when euglyphids arose is uncertain. Current fossil record contains unambiguous euglyphid fossils that are as old as 50 million years, but older fossils are scarce and difficult to interpret. Poor taxon sampling of euglyphids has also prevented the development of molecular clocks. Here, we present a novel molecular clock reconstruction for arcellinids and consider the uncertainties due to various previously used calibration points. The new molecular clock puts the origin of hyalosphenids in the early Carboniferous (∼370 mya). Notably, this estimate coincides with the widespread colonization of land by Si-accumulating plants, suggesting possible links between the evolution of Arcellinid testate amoebae and the expansion of terrestrial habitats rich in organic matter and bioavailable Si. PMID:26734499

  4. Remarkable Anti-Trichomonas vaginalis Activity of Plants Traditionally Used by the Mbyá-Guarani Indigenous Group in Brazil

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    Clara Lia Costa Brandelli

    2013-01-01

    Full Text Available Trichomonas vaginalis, a flagellate protozoan, is the causative agent of trichomonosis, the most common nonviral sexually transmitted disease worldwide. Taking into account the increased prevalence of metronidazole-resistant isolates, alternative drugs are essential for the successful treatment. Natural products are the source of most new drugs, and popular wisdom about the use of medicinal plants is a powerful tool in this search. In this study, the activity of 10 medicinal plants extensively used in daily life by Mbyá-Guarani indigenous group was evaluated against seven different T. vaginalis isolates. Among the aqueous extracts tested, Verbena sp. (Guachu ka'a in Mbyá-Guarani language and Campomanesia xanthocarpa (Guavira in Mbyá-Guarani language showed the highest activity against T. vaginalis with MIC value of 4.0 mg/mL reaching 100% of efficacy against the parasite. The kinetic growth assays showed that the extracts promoted complete growth abolishment after 4 h of incubation. In addition, the extracts tested did not promote a significant hemolytic activity against human erythrocytes. Our results show for the first time the potential activity of Verbena sp. and C. xanthocarpa against T. vaginalis. In addition, this study demonstrates that indigenous knowledge is an important source of new prototype antiprotozoal agents.

  5. Network of interactions between ciliates and phytoplankton during spring

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    Thomas ePosch

    2015-11-01

    Full Text Available The annually recurrent spring phytoplankton blooms in freshwater lakes initiate pronounced successions of planktonic ciliate species. Although there is considerable knowledge on the taxonomic diversity of these ciliates, their species-specific interactions with other microorganisms are still not well understood. Here we present the succession patterns of 20 morphotypes of ciliates during spring in Lake Zurich, Switzerland, and we relate their abundances to phytoplankton genera, flagellates, heterotrophic bacteria, and abiotic parameters. Interspecific relationships were analyzed by contemporaneous correlations and time-lagged co-occurrence and visualized as association networks. The contemporaneous network pointed to the pivotal role of distinct ciliate species (e.g., Balanion planctonicum, Rimostrombidium humile as primary consumers of cryptomonads, revealed a clear overclustering of mixotrophic / omnivorous species, and highlighted the role of Halteria / Pelagohalteria as important bacterivores. By contrast, time-lagged statistical approaches (like local similarity analyses, LSA proved to be inadequate for the evaluation of high-frequency sampling data. LSA led to a conspicuous inflation of significant associations, making it difficult to establish ecologically plausible interactions between ciliates and other microorganisms. Nevertheless, if adequate statistical procedures are selected, association networks can be powerful tools to formulate testable hypotheses about the autecology of only recently described ciliate species.

  6. The Fantastic Voyage of the Trypanosome: A Protean Micromachine Perfected during 500 Million Years of Engineering

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    Timothy Krüger

    2018-02-01

    Full Text Available The human body is constantly attacked by pathogens. Various lines of defence have evolved, among which the immune system is principal. In contrast to most pathogens, the African trypanosomes thrive freely in the blood circulation, where they escape immune destruction by antigenic variation and incessant motility. These unicellular parasites are flagellate microswimmers that also withstand the harsh mechanical forces prevailing in the bloodstream. They undergo complex developmental cycles in the bloodstream and organs of the mammalian host, as well as the disease-transmitting tsetse fly. Each life cycle stage has been shaped by evolution for manoeuvring in distinct microenvironments. Here, we introduce trypanosomes as blueprints for nature-inspired design of trypanobots, micromachines that, in the future, could explore the human body without affecting its physiology. We review cell biological and biophysical aspects of trypanosome motion. While this could provide a basis for the engineering of microbots, their actuation and control still appear more like fiction than science. Here, we discuss potentials and challenges of trypanosome-inspired microswimmer robots.

  7. Comparative evaluations of the detection of antinuclear antibodies by means of various immunofluorescence techniques and by means of a radioimmunoassay under particular consideration of disseminated Lupus erythematodus

    International Nuclear Information System (INIS)

    Gemuend, R.

    1980-01-01

    On a group of 146 test persons (in 50 cases desseminated lupus erythematodus had been confirmed), for the first time comparative evaluations were made with four methods (A to D) under the application of a repurified fluorescinisothiocyanat FITC) serum, in order to detect antinuclear antibodies (ANA). The ANA detection was obtained by immunofluorescence (IFL) on frozen sections of mouse livers; by IFL on chicken erythrocytes smears, previously treated with hydrochloric acid; by IFL on ethanol-fixed flagellates Crithidia luciliae; and by the radioimmunoassay (RIA) of a test kit with reference sera. These two tests served to detect antibodies - with respect to negative DNA - which are of particular importance in lupous nephritis. A good correlation of both methods was proved by means of various statistic methods and by follow-up observations and examinations of the reference sera. Possible reasons responsible for the deviations, which were found between the two tests, are described. Of all 4 tests, RIA and IFL on Crithida resulted to be the most closely ones to the relevant laboratory values and reflect very evidently the activity of the desseminated lupus erethematodus. The particularly well correlation with the blood sedimentation rate, proteinuria and with the complement level becomes very obvious. The advantages and disadvantages of the applied methods are discussed and it is emphasized that at present the method of choice for the detection of DNA antibodies is the combined examination of the patient serum, both, in the IFL on Crithidia and in the RIA. (orig./MG) [de

  8. Canine visceral leishmaniasis in the metropolitan area of São Paulo: Pintomyia fischeri as potential vector of Leishmania infantum

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    Galvis-Ovallos Fredy

    2017-01-01

    Full Text Available American visceral leishmaniasis is a zoonosis caused by Leishmania infantum and transmitted mainly by Lutzomyia longipalpis. However, canine cases have been reported in the absence of this species in the Greater São Paulo region, where Pintomyia fischeri and Migonemyia migonei are the predominant species. This raises the suspicion that they could be acting as vectors. Therefore, this study sought to investigate specific vector capacity parameters of these species and to compare them with those of Lu. longipalpis s.l. Among these parameters the blood feeding rate, the survival, and the susceptibility to the development of Le. infantum were evaluated for the three species, and the attractiveness of dogs to Pi. fischeri and Mg. migonei was evaluated. The estimated interval between blood meals was shorter for Lu. longipalpis s.l, followed by Pi. fischeri and Mg. migonei. The infection rate with Le. infantum flagellates in Lu. longipalpis was 9.8%, in Pi. fischeri 4.8%, and in Mg. migonei nil. The respective infective life expectancies (days of Lu. longipalpis, Mg. migonei, and Pi. fischeri were 2.4, 1.94, and 1.68. Both Pi. fischeri and Mg. migonei were captured in the kennel with a predominance (95% of Pi. fischeri. Considering the great attractiveness of dogs to Pi. fischeri, its susceptibility to infection by Le. infantum, infective life expectancies, and predominance in Greater São Paulo, this study presents evidence of Pi. fischeri as a potential vector of this parasite in the region.

  9. [A brief history of resuscitation - the influence of previous experience on modern techniques and methods].

    Science.gov (United States)

    Kucmin, Tomasz; Płowaś-Goral, Małgorzata; Nogalski, Adam

    2015-02-01

    Cardiopulmonary resuscitation (CPR) is relatively novel branch of medical science, however first descriptions of mouth-to-mouth ventilation are to be found in the Bible and literature is full of descriptions of different resuscitation methods - from flagellation and ventilation with bellows through hanging the victims upside down and compressing the chest in order to stimulate ventilation to rectal fumigation with tobacco smoke. The modern history of CPR starts with Kouwenhoven et al. who in 1960 published a paper regarding heart massage through chest compressions. Shortly after that in 1961Peter Safar presented a paradigm promoting opening the airway, performing rescue breaths and chest compressions. First CPR guidelines were published in 1966. Since that time guidelines were modified and improved numerously by two leading world expert organizations ERC (European Resuscitation Council) and AHA (American Heart Association) and published in a new version every 5 years. Currently 2010 guidelines should be obliged. In this paper authors made an attempt to present history of development of resuscitation techniques and methods and assess the influence of previous lifesaving methods on nowadays technologies, equipment and guidelines which allow to help those women and men whose life is in danger due to sudden cardiac arrest. © 2015 MEDPRESS.

  10. Remarkable anti-trichomonas vaginalis activity of plants traditionally used by the Mbyá-Guarani indigenous group in Brazil.

    Science.gov (United States)

    Brandelli, Clara Lia Costa; Vieira, Patrícia de Brum; Macedo, Alexandre José; Tasca, Tiana

    2013-01-01

    Trichomonas vaginalis, a flagellate protozoan, is the causative agent of trichomonosis, the most common nonviral sexually transmitted disease worldwide. Taking into account the increased prevalence of metronidazole-resistant isolates, alternative drugs are essential for the successful treatment. Natural products are the source of most new drugs, and popular wisdom about the use of medicinal plants is a powerful tool in this search. In this study, the activity of 10 medicinal plants extensively used in daily life by Mbyá-Guarani indigenous group was evaluated against seven different T. vaginalis isolates. Among the aqueous extracts tested, Verbena sp. (Guachu ka'a in Mbyá-Guarani language) and Campomanesia xanthocarpa (Guavira in Mbyá-Guarani language) showed the highest activity against T. vaginalis with MIC value of 4.0 mg/mL reaching 100% of efficacy against the parasite. The kinetic growth assays showed that the extracts promoted complete growth abolishment after 4 h of incubation. In addition, the extracts tested did not promote a significant hemolytic activity against human erythrocytes. Our results show for the first time the potential activity of Verbena sp. and C. xanthocarpa against T. vaginalis. In addition, this study demonstrates that indigenous knowledge is an important source of new prototype antiprotozoal agents.

  11. The ecological coherence of temperature and salinity tolerance interaction and pigmentation in a non-marine vibrio isolated from Salar de Atacama

    Directory of Open Access Journals (Sweden)

    Karem Gallardo

    2016-12-01

    Full Text Available The occurrence of microorganisms from the Vibrio genus in saline lakes from northern Chile had been evidenced using Numerical Taxonomy decades before and, more recently, by phylogenetic analyses of environmental samples and isolates. Most of the knowledge about this genus came from marine isolates and showed temperature and salinity to be integral agents in shaping the niche of the Vibrio populations. The stress tolerance phenotypes of Vibrio sp. Teb5a1 isolated from Salar de Atacama was investigated. It was able to grow without NaCl and tolerated up to 100 g/L of the salt. Furthermore, it grew between 17° and 49°C (optimum 30°C in the absence of NaCl, and the range was expanded into cold temperature (4-49°C in the presence of the salt. Other additional adaptive strategies were observed in response to the osmotic stress: pigment production, identified as the known antibacterial prodigiosin, swimming and swarming motility and synthesis of a polar flagellum. It is possible to infer that environmental congruence might explain the cellular phenotypes observed in Vibrio sp. considering that coupling between temperature and salinity tolerance, the production of antibacterial agents at higher temperatures, flagellation and motility increase the chance of Vibrio sp. to survive in salty environments with high daily temperature swings and UV radiation.

  12. Effect of grazers and viruses on bacterial community structure and production in two contrasting trophic lakes

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    Domaizon Isabelle

    2011-04-01

    Full Text Available Abstract Background Over the last 30 years, extensive studies have revealed the crucial roles played by microbes in aquatic ecosystems. It has been shown that bacteria, viruses and protozoan grazers are dominant in terms of abundance and biomass. The frequent interactions between these microbiological compartments are responsible for strong trophic links from dissolved organic matter to higher trophic levels, via heterotrophic bacteria, which form the basis for the important biogeochemical roles of microbial food webs in aquatic ecosystems. To gain a better understanding of the interactions between bacteria, viruses and flagellates in lacustrine ecosystems, we investigated the effect of protistan bacterivory on bacterial abundance, production and structure [determined by 16S rRNA PCR-DGGE], and viral abundance and activity of two lakes of contrasting trophic status. Four experiments were conducted in the oligotrophic Lake Annecy and the mesotrophic Lake Bourget over two seasons (early spring vs. summer using a fractionation approach. In situ dark vs. light incubations were performed to consider the effects of the different treatments in the presence and absence of phototrophic activity. Results The presence of grazers (i.e. Conclusions Our results highlight the importance of a synergistic effect, i.e. the positive influence of grazers on viral activities in sustaining (directly and indirectly bacterial production and affecting composition, in both oligotrophic and mesotrophic lakes.

  13. Modeling the locomotion of the African trypanosome using multi-particle collision dynamics

    International Nuclear Information System (INIS)

    Babu, Sujin B; Stark, Holger

    2012-01-01

    The African trypanosome is a single flagellated micro-organism that causes the deadly sleeping sickness in humans and animals. We study the locomotion of a model trypanosome by modeling the spindle-shaped cell body using an elastic network of vertices with additional bending rigidity. The flagellum firmly attached to the model cell body is either straight or helical. A bending wave propagates along the flagellum and pushes the trypanosome forward in its viscous environment, which we simulate with the method of multi-particle collision dynamics. The relaxation dynamics of the model cell body due to a static bending wave reveals the sperm number from elastohydrodynamics as the relevant parameter. Characteristic cell body conformations for the helically attached flagellum resemble experimental observations. We show that the swimming velocity scales as the root of the angular frequency of the bending wave reminiscent of predictions for an actuated slender rod attached to a large viscous load. The swimming velocity for one geometry collapses on a single master curve when plotted versus the sperm number. The helically attached flagellum leads to a helical swimming path and a rotation of the model trypanosome about its long axis as observed in experiments. The simulated swimming velocity agrees with the experimental value. (paper)

  14. Heterokont predator Develorapax marinus gen. et sp. nov. – a model of the ochrophyte ancestor

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    Vladimir V. Aleoshin

    2016-08-01

    Full Text Available Heterotrophic lineages of Heterokonta (or stramenopiles, in contrast to a single monophyletic group of autotrophs, Ochrophyta, form several clades that independently branch off the heterokont stem lineage. The nearest neighbors of Ochrophyta in the phylogenetic tree appear to be almost exclusively bacterivorous, whereas the hypothesis of plastid acquisition by the ancestors of the ochrophyte lineage suggests an ability to engulf eukaryotic alga. In line with this hypothesis, the heteretrophic predator at the base of the ochrophyte lineage may be regarded as a model for the ochrophyte ancestor. Here we present a new genus and species of marine free-living heterotrophic heterokont Develorapax marinus, which falls into an isolated heterokont cluster, along with the marine flagellate Developayella elegans, and is able to engulf eukaryotic cells. Together with environmental sequences D. marinus and D. elegans form a class-level clade Developea nom. nov. represented by species adapted to different environmental conditions and with a wide geographical distribution. The position of Developea among Heterokonta in large-scale phylogenetic tree is discussed. We propose that members of the Developea clade represent a model for transition from bacterivory to a predatory feeding mode by selection for larger prey. Presumably, such transition in the grazing strategy is possible in the presence of bacterial biofilms, and has likely occured in the ochrophyte ancestor.

  15. Phylogenomic Analyses Indicate that Early Fungi Evolved Digesting Cell Walls of Algal Ancestors of Land Plants

    Science.gov (United States)

    Chang, Ying; Wang, Sishuo; Sekimoto, Satoshi; Aerts, Andrea L.; Choi, Cindy; Clum, Alicia; LaButti, Kurt M.; Lindquist, Erika A.; Yee Ngan, Chew; Ohm, Robin A.; Salamov, Asaf A.; Grigoriev, Igor V.; Spatafora, Joseph W.; Berbee, Mary L.

    2015-01-01

    As decomposers, fungi are key players in recycling plant material in global carbon cycles. We hypothesized that genomes of early diverging fungi may have inherited pectinases from an ancestral species that had been able to extract nutrients from pectin-containing land plants and their algal allies (Streptophytes). We aimed to infer, based on pectinase gene expansions and on the organismal phylogeny, the geological timing of the plant–fungus association. We analyzed 40 fungal genomes, three of which, including Gonapodya prolifera, were sequenced for this study. In the organismal phylogeny from 136 housekeeping loci, Rozella diverged first from all other fungi. Gonapodya prolifera was included among the flagellated, predominantly aquatic fungal species in Chytridiomycota. Sister to Chytridiomycota were the predominantly terrestrial fungi including zygomycota I and zygomycota II, along with the ascomycetes and basidiomycetes that comprise Dikarya. The Gonapodya genome has 27 genes representing five of the seven classes of pectin-specific enzymes known from fungi. Most of these share a common ancestry with pectinases from Dikarya. Indicating functional and sequence similarity, Gonapodya, like many Dikarya, can use pectin as a carbon source for growth in pure culture. Shared pectinases of Dikarya and Gonapodya provide evidence that even ancient aquatic fungi had adapted to extract nutrients from the plants in the green lineage. This implies that 750 million years, the estimated maximum age of origin of the pectin-containing streptophytes represents a maximum age for the divergence of Chytridiomycota from the lineage including Dikarya. PMID:25977457

  16. Saharan Dust Deposition Effects on the Microbial Food Web in the Eastern Mediterranean: A Study Based on a Mesocosm Experiment

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    Paraskevi Pitta

    2017-05-01

    Full Text Available The effect of episodicity of Saharan dust deposition on the pelagic microbial food web was studied in the oligotrophic Eastern Mediterranean by means of a mesocosm experiment in May 2014. Two different treatments in triplicates (addition of natural Saharan dust in a single-strong pulse or in three smaller consecutive doses of the same total quantity, and three unamended controls were employed; chemical and biological parameters were measured during a 10-day experiment. Temporal changes in primary (PP and bacterial (BP production, chlorophyll a (Chl a concentration and heterotrophic bacteria, Synechococcus and mesozooplankton abundance were studied. The results suggested that the auto- and hetero-trophic components of the food web (at least the prokaryotes were enhanced by the dust addition (and by the nitrogen and phosphorus added through dust. Furthermore, a 1-day delay was observed for PP, BP, and Chl a increases when dust was added in three daily doses; however, the maximal values attained were similar in the two treatments. Although, the effect was evident in the first osmotrophic level (phytoplankton and bacteria, it was lost further up the food web, masked under the impact of grazing exerted by predators such as heterotrophic flagellates, ciliates and dinoflagellates. This was partly proved by two dilution experiments. This study demonstrates the important role of atmospheric deposition and protist grazing when evaluating the effect on oligotrophic systems characterized by increased numbers of trophic levels.

  17. The Bacterial Symbiont Phaeobacter inhibens Shapes the Life History of Its Algal Host Emiliania huxleyi

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    Anna R. Bramucci

    2018-05-01

    Full Text Available Marine microbes form host-associated biofilm communities that are shaped by complex interactions between bacteria and their host. The roseobacter Phaeobacter inhibens exploits both symbiotic and pathogenic niches while interacting with its microalgal host Emiliania huxleyi. During co-cultivation over extended periods with E. huxleyi, we show that P. inhibens selectively kills two host cell types, the diploid calcifying strain and the haploid flagellated strain. Meanwhile, various non-calcifying diploid strains are resistant to this pathogen or the pathogen is avirulent to this cell type. This differential pathogenesis has the potential of dramatically altering the composition of E. huxleyi blooms, which are typically dominated by the roseobacter-susceptible calcifying strain. This cell type makes calcite plates, which are an important sink in the marine carbon cycle and forms part of the marine paleobotanic record. P. inhibens kills the haploid cells, which have been proposed as critical to the survival of the algae, as they readily escape both eukaryotic predation and viral infection. Consequently, bacteria such as P. inhibens could influence E. huxleyi's life history by selective pathogenesis, thereby altering the composition of cell types within E. huxleyi populations and its bloom-bust lifestyle.

  18. The effect of visible light stress on chemical signaling in two life stages of Emiliania huxleyi

    Science.gov (United States)

    Valentin-Alvarado, L.; Cooney, E.; Bright, K.; Strom, S.

    2016-02-01

    The cosmopolitan marine phytoplankton species Emiliania huxleyi presents a digenetic heteromorphic life cycle, with the non-motile diploid phase bearing coccoliths and the flagellated haploid phase being non-calcified. E. huxleyi contains high concentrations of dimethylsulphoniopropionate (DMSP), the precursor of dimethylsulphide (DMS). DMSP is a multifactorial compound; it acts as a compatible solute in cell metabolism and as a chemical signal influencing bacterial and protist behavior. In the atmosphere DMS enhances cloud formation influencing climate. However, little has been documented on E. huxleyi chemical signal responses to high light stress, and how this relates to the heteromorphic life cycle. To this end, low light acclimated cultures of both haploid and diploid E. huxleyi were exposed to high light for 2 hr and allowed to recover in low light for 2 hr. During and after these treatments, growth, photosynthetic efficiency (Fv/Fm), DMSP (intracellular and released) and cell chlorophyll content were measured. Our preliminary results suggest that presence of high light decreased Fv/Fm to a greater extent in haploid than in diploid (calcified) cells, while recovery of Fv/Fm was rapid in both life stages. The chlorophyll content and intracellular DMSP was not different in both life stages. However, the dissolved DMSP increased after light stress in diploid cells suggesting a possible advantage as antioxidant protection or another cellular function, such as grazing protection in this life stage.

  19. In situ survey of life cycle phases of the coccolithophore Emiliania huxleyi (Haptophyta).

    Science.gov (United States)

    Frada, Miguel J; Bidle, Kay D; Probert, Ian; de Vargas, Colomban

    2012-06-01

    The cosmopolitan coccolithophore Emiliania huxleyi is characterized by a strongly differentiated haplodiplontic life cycle consisting of a diploid phase, generally bearing coccoliths (calcified) but that can be also non-calcified, and a non-calcified biflagellated haploid phase. Given most studies have focused on the bloom-producing calcified phase, there is little-to-no information about non-calcified cells in nature. Using field mesocoms as experimental platforms, we quantitatively surveyed calcified and non-calcified cells using the combined calcareous detection fluorescent in situ hybridization (COD-FISH) method and qualitatively screened for haploid specific transcripts using reverse transcription-PCR during E. huxleyi bloom successions. Diploid, calcified cells formed dense blooms that were followed by the massive proliferation of E. huxleyi viruses (EhVs), which caused bloom demise. Non-calcified cells were also detected throughout the experiment, accounting for a minor fraction of the population but becoming progressively more abundant during mid-late bloom periods concomitant with EhV burst. Non-calcified cell growth also paralleled a distinct window of haploid-specific transcripts and the appearance of autotrophic flagellates morphologically similar to haploid cells, both of which are suggestive of meiosis and sexual life cycling during natural blooms of this prominent marine phytoplankton species. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  20. Effects of altered temperature and precipitation on desert protozoa associated with biological soil crusts.

    Science.gov (United States)

    Darby, Brian J; Housman, David C; Zaki, Amr M; Shamout, Yassein; Adl, Sina M; Belnap, Jayne; Neher, Deborah A

    2006-01-01

    Biological soil crusts are diverse assemblages of bacteria, cyanobacteria, algae, fungi, lichens, and mosses that cover much of arid land soils. The objective of this study was to quantify protozoa associated with biological soil crusts and test the response of protozoa to increased temperature and precipitation as is predicted by some global climate models. Protozoa were more abundant when associated with cyanobacteria/lichen crusts than with cyanobacteria crusts alone. Amoebae, flagellates, and ciliates originating from the Colorado Plateau desert (cool desert, primarily winter precipitation) declined 50-, 10-, and 100-fold, respectively, when moved in field mesocosms to the Chihuahuan Desert (hot desert, primarily summer rain). However, this was not observed in protozoa collected from the Chihuahuan Desert and moved to the Sonoran desert (hot desert, also summer rain, but warmer than Chihuahuan Desert). Protozoa in culture began to encyst at 37 degrees C. Cysts survived the upper end of daily temperatures (37-55 degrees C), and could be stimulated to excyst if temperatures were reduced to 15 degrees C or lower. Results from this study suggest that cool desert protozoa are influenced negatively by increased summer precipitation during excessive summer temperatures, and that desert protozoa may be adapted to a specific desert's temperature and precipitation regime.

  1. Occurrence of synanthropic triatomines (Hemiptera: Reduviidae in the Federal District of Brazil

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    Maicon Hitoshi Maeda

    2012-02-01

    Full Text Available INTRODUCTION: Entomological surveillance of Chagas disease in the Federal District of Brazil (DF, has recorded the following triatomine species: Panstrongylus megistus, P. geniculatus, P. diasi, Rhodnius neglectus, Triatoma pseudomaculata, and T. sordida. We aimed to analyze the spatial and temporal occurrence of triatomine species collected in DF, and their indices of natural infection with trypanosomes. METHODS: The Health State Secretariat of DF recorded triatomines between 2002 and 2010 in 20 administrative regions. This retrospective analysis considered the number of adults and nymphs of each species collected and infected in both intradomicile and peridomicile. RESULTS: A total of 754 triatomines were collected in 252 reported domiciles. Panstrongylus megistus was the most frequent species (65%, followed by T. pseudomaculata (14%. Of the 309 examined insects, only 3 (1% specimens of P. megistus were infected with flagellates morphologically similar to Trypanosoma cruzi. The spatial occurrence indicated a higher diversity of triatomines and frequency of T. sordida in rural areas. Moreover, there was a predominance of P. megistus in urban areas. The number of records of P. megistus in the rainy season was two times higher than that during the dry season. The largest number of triatomines was collected in November. CONCLUSIONS: The presence of P. megistus specimens infected with trypanosomes in domiciles, shows the potential risk of human infection in DF. Thus, it is essential to continue entomological surveillance, intensifying it in the rainy season and in regions of greater occurrence.

  2. Survey the Outbreak of Giardiasis Among Food Supply and Distribution Staff of South Pars Economic Zone Petrochemicals

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    Sadegh Niazi

    2013-12-01

    Full Text Available Background & Objectives: Giardiasis is one of the parasitic infections in the gastrointestinal tract which caused by flagellate protozoa that called giardia and it causes diarrhea. Giardia cysts defecate from infected people. These cysts can enter the body through contaminated hands, water, and food products. Diarrhea, weight loss, abdominal pains, growth failure, malabsorption of carbohydrates, fats and vitamins are the giardiasis symptoms. Methods: In this study, samples were taken from 203 people that were working in different food supply and distribution centers in the South Pars petrochemical. After sampling, samples were analyzed according to standard procedures. The results of examinations were studied after verification them by laboratory chief and their related physicians. Results: Out of the whole examined people in this study, kitchen (28% and salad maker (14% centers were the maximum and minimum population, respectively. 8.87% of the total populations were infected by giardia, which salad making center had the greatest share. As well as, the rate of infectious by giardia among the administrative and dishes washing centers was the lowest. Conclusion: Education level and personal hygiene such as hand washing with a detergent can be important in reducing infection due to giardia. So, the training of workers and also periodic testing of individuals can reduce these pollutants.

  3. First human cases of Leishmania (Viannia) naiffi infection in Ecuador and identification of its suspected vector species.

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    Kato, Hirotomo; Calvopiña, Manuel; Criollo, Hipatia; Hashiguchi, Yoshihisa

    2013-12-01

    Epidemiological surveillance of leishmaniasis was conducted in a northern Amazonian region of Ecuador, in which cutaneous leishmaniasis cases were recently reported. Sand flies were captured in the military training camp, and the natural infection of sand flies by Leishmania species was examined. Out of 334 female sand flies dissected, the natural infection by flagellates was microscopically detected in 3.9% of Lutzomyia yuilli yuilli and 3.7% of Lutzomyia tortura, and the parasite species were identified as Endotrypanum and Leishmania (Viannia) naiffi, respectively. After the sand fly surveillance, specimens from cutaneous leishmaniasis (CL) patients considered to have acquired the infection in the training camp area were obtained, and the infected parasite species were identified as L. (V.) naiffi. The present study reported first cases of CL caused by L. (V.) naiffi infection in Ecuador. In addition, a high ratio of infection of Lu. tortura by L. (V.) naiffi in the same area strongly suggested that Lu. tortura is responsible for the transmission of L. (V.) naiffi in this area. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Cutaneous reaction associated with weekly docetaxel administration.

    Science.gov (United States)

    Chew, Lita; Chuen, Vivianne Shih Lee

    2009-03-01

    Docetaxel-based chemotherapy will remain clinically relevant and many of our patients will continue to receive the drug. In a recent phase 2 study of docetaxel 35 mg/m2 (weekly) in patients with metastatic breast cancer, the incidence of grade 3 cutaneous toxicity is 19%. The skin toxicity observed consists of limb/palmar-plantar erythematous reactions, or fixed-plaque erythrodysesthesia. Case series or reports have reported varied manifestations of skin reactions and include erythema multiforme, nail changes (onycholysis, pigmentation, paronychia), scleroderma, supravenous discoloration, radiation recall dermatitis, and flagellate erythema. We would like to report four patients with cutaneous reactions resulting from weekly administration of docetaxel. All cases are heavily pre-treated patients, receiving docetaxel as second or third line therapy. The cutaneous reactions occur at cycle 5. The time between chemotherapy to development of skin lesions is from 1 to 7 days. Lesions usually resolve with desquamation leaving behind areas with hyper-pigmentation or hypo-pigmentation over a period of 2 to 3 weeks. The management strategies include hand elevation, warm or cold compresses, topical and/or systemic antibiotics, topical and/or systemic corticosteroids, and cessation of drug. There is a need for a systematic approach to manage these cutaneous reactions. Oncology trained pharmacists play vital roles in assessing, managing, documenting and patient education.

  5. Gravitactic orientation of Euglena gracilis – a sensitive endpoint for ecotoxicological assessment of water pollutants

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    Aziz eUllah

    2013-12-01

    Full Text Available Pollution of aquatic environments with natural and anthropogenically produced substances is one of the major environmental problems of the world. In many countries the decreasing quantity of water coupled with its increasing usage in multiple sectors has adversely affected water quality and caused problems of water pollution. Polluted water has been a main cause of adverse effects on plants, animals and humans throughout the world. Physicochemical analysis of water, which is a common method used for quality assessment of water, alone may not be enough as it cannot evaluate the impact on living organisms. Therefore, bioassessment of water and wastewater quality is considered to be essential to reflect the ultimate effects on living organisms. Many organisms like bacteria, algae, fish, invertebrates and protozoan are used as bioassay organisms for assessment of water quality. This review article elucidates the use of Euglena gracilis, a freshwater motile flagellate of the phylum Euglenophyta, as a suitable organism in ecotoxicological studies with special emphasis on its gravitactic orientation as a sensitive end point in ecotoxicological assessment of water pollutants.

  6. Pseudomonas aestus sp. nov., a plant growth-promoting bacterium isolated from mangrove sediments.

    Science.gov (United States)

    Vasconcellos, Rafael L F; Santos, Suikinai Nobre; Zucchi, Tiago Domingues; Silva, Fábio Sérgio Paulino; Souza, Danilo Tosta; Melo, Itamar Soares

    2017-10-01

    Strain CMAA 1215 T , a Gram-reaction-negative, aerobic, catalase positive, polarly flagellated, motile, rod-shaped (0.5-0.8 × 1.3-1.9 µm) bacterium, was isolated from mangrove sediments, Cananéia Island, Brazil. Analysis of the 16S rRNA gene sequences showed that strain CMAA 1215 T forms a distinct phyletic line within the Pseudomonas putida subclade, being closely related to P. plecoglossicida ATCC 700383 T , P. monteilii NBRC 103158 T , and P. taiwanensis BCRC 17751 T of sequence similarity of 98.86, 98.73, and 98.71%, respectively. Genomic comparisons of the strain CMAA 1215 T with its closest phylogenetic type strains using average nucleotide index (ANI) and DNA:DNA relatedness approaches revealed 84.3-85.3% and 56.0-63.0%, respectively. A multilocus sequence analysis (MLSA) performed concatenating 16S rRNA, gyrB and rpoB gene sequences from the novel species was related with Pseudomonas putida subcluster and formed a new phylogenetic lineage. The phenotypic, physiological, biochemical, and genetic characteristics support the assignment of CMAA 1215 T to the genus Pseudomonas, representing a novel species. The name Pseudomonas aestus sp.nov. is proposed, with CMAA 1215 T (=NRRL B-653100 T  = CBMAI 1962 T ) as the type strain.

  7. Silicon utilizing microorganisms in the sea act as the environmental bellwether which foretell future trends in weather fluctuations

    Science.gov (United States)

    Das, S.

    2012-12-01

    It is well known that the southerly shift of the Gulf Stream is associated with major storms, heavy rains and mudslide in the adjoining northern part of the globe. Phytoplanktons particularly their silicon utilizing members like diatoms were found to play a major part in this phenomenon. A decrease in silicon utilizing phytoplanktons and chlorophyll-a , which sometimes occurs even more than 10 fold was found associated with a parallel significant decrease of zooplanktons as reflected in the CPR survey, leads to fall of sea temperature causing a shift of the Gulf Stream. This sea temperature changes is also associated with cooling of the adjoining atmosphere in a remarkable way which leads to weather changes. The association of silicon utilizing diatoms and the ocean currents guides the future trends in the climatic swing known as NAO, one of the great fluctuations that occur in the global climate, the largest of which is the ENSO phenomenon in the Pacific Ocean, which cause destruction all around the tropics. When total density and biovolume of phytoplanktons were studied it was found that the changes of pennate diatoms was unique and occurred in an opposite way in comparison to green algae, blue green algae, chrysophyte, cryptophytes, dinoflagellates and green flagellates.

  8. SAS6-like protein in Plasmodium indicates that conoid-associated apical complex proteins persist in invasive stages within the mosquito vector.

    Science.gov (United States)

    Wall, Richard J; Roques, Magali; Katris, Nicholas J; Koreny, Ludek; Stanway, Rebecca R; Brady, Declan; Waller, Ross F; Tewari, Rita

    2016-06-24

    The SAS6-like (SAS6L) protein, a truncated paralogue of the ubiquitous basal body/centriole protein SAS6, has been characterised recently as a flagellum protein in trypanosomatids, but associated with the conoid in apicomplexan Toxoplasma. The conoid has been suggested to derive from flagella parts, but is thought to have been lost from some apicomplexans including the malaria-causing genus Plasmodium. Presence of SAS6L in Plasmodium, therefore, suggested a possible role in flagella assembly in male gametes, the only flagellated stage. Here, we have studied the expression and role of SAS6L throughout the Plasmodium life cycle using the rodent malaria model P. berghei. Contrary to a hypothesised role in flagella, SAS6L was absent during gamete flagellum formation. Instead, SAS6L was restricted to the apical complex in ookinetes and sporozoites, the extracellular invasive stages that develop within the mosquito vector. In these stages SAS6L forms an apical ring, as we show is also the case in Toxoplasma tachyzoites. The SAS6L ring was not apparent in blood-stage invasive merozoites, indicating that the apical complex is differentiated between the different invasive forms. Overall this study indicates that a conoid-associated apical complex protein and ring structure is persistent in Plasmodium in a stage-specific manner.

  9. Deduction of upstream sequences of Xanthomonas campestris flagellar genes responding to transcription activation by FleQ

    International Nuclear Information System (INIS)

    Hu, R.-M.; Yang, T.-C.; Yang, S.-H.; Tseng, Y.-H.

    2005-01-01

    Xanthomonas campestris pv. campestris (Xcc), a close relative to Pseudomonas aeruginosa, is the pathogen causing black rot in cruciferous plants. In P. aeruginosa, FleQ serves as a cognate activator of σ 54 in transcription from several σ 54 -dependent promoters of flagellar genes. These P. aeruginosa promoters have been analyzed for FleQ-binding sequences; however, no consensus was deduced. Xcc, although lacks fleSR, has a fleQ homologue residing among over 40 contiguously clustered flagellar genes. A fleQ mutant, Xc17fleQ, constructed by insertional mutation is deficient in FleQ protein, non-flagellated, and immobile. Transcriptional fusion assays on six putative σ 54 -dependent promoters of the flagellar genes, fliE, fliQ, fliL, flgG, flgB, and flhF, indicated that each of them is also FleQ dependent. Each of these promoters has a sequence with weak consensus to 5'-gaaacCCgccgCcgctTt-3', immediately upstream of the predicted σ 54 -binding site, with an imperfect inverted repeat containing a GC-rich center flanked by several A and T at 5'- and 3'-ends, respectively. Replacing this region in fliE promoter with a HindIII recognition sequence abolished the transcription, indicating that this region responds to transcription activation by FleQ

  10. Structured attachment of bacterial molecular motors for defined microflow induction

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    Woerdemann Mike

    2014-01-01

    Full Text Available Bacterial rotational motor complexes that propel flagellated bacteria possess unique properties like their size of a few nanometres and the ability of selfreproduction that have led to various exciting applications including biohybrid nano-machines. One mandatory prerequisite to utilize bacterial nano motors in fluid applications is the ability to transfer force and torque to the fluid, which usually can be achieved by attachment of the bacterial cell to adequate surfaces. Additionally, for optimal transfer of force or torque, precise control of the position down to the single cell level is of utmost importance. Based on a PIV (particle image velocimetry evaluation of the induced flow of single bacteria,we propose and demonstrate attachment of arbitrary patterns of motile bacterial cells in a fast light-based two-step process for the first time to our knowledge. First, these cells are pre-structured by holographic optical tweezers and then attached to a homogeneous, polystyrene-coated surface. In contrast to the few approaches that have been implemented up to now and which rely on pre-structured surfaces, our scheme allows for precise control on a single bacterium level, is versatile, interactive and has low requirements with respect to the surface preparation.

  11. Development of a rapid HRM genotyping method for detection of dog-derived Giardia lamblia.

    Science.gov (United States)

    Tan, Liping; Yu, Xingang; Abdullahi, Auwalu Yusuf; Wu, Sheng; Zheng, Guochao; Hu, Wei; Song, Meiran; Wang, Zhen; Jiang, Biao; Li, Guoqing

    2015-11-01

    Giardia lamblia is a zoonotic flagellate protozoan in the intestine of human and many mammals including dogs. To assess a threat of dog-derived G. lamblia to humans, the common dog-derived G. lamblia assemblages A, C, and D were genotyped by high-resolution melting (HRM) technology. According to β-giardin gene sequence, the qPCR-HRM primers BG5 and BG7 were designed. A series of experiments on the stability, sensitivity, and accuracy of the HRM method were also tested. Results showed that the primers BG5 and BG7 could distinguish among three assemblages A, C, and D, which Tm value differences were about 1 °C to each other. The melting curves of intra-assay reproducibility were almost coincided, and those of inter-assay reproducibility were much the same shape. The lowest detection concentration was about 5 × 10(-6)-ng/μL sample. The genotyping results from 21 G. lamblia samples by the HRM method were in complete accordance with sequencing results. It is concluded that the HRM genotyping method is rapid, stable, specific, highly sensitive, and suitable for clinical detection and molecular epidemiological survey of dog-derived G. lamblia.

  12. The crystal structure of Giardia duodenalis 14-3-3 in the apo form: when protein post-translational modifications make the difference.

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    Annarita Fiorillo

    Full Text Available The 14-3-3s are a family of dimeric evolutionary conserved pSer/pThr binding proteins that play a key role in multiple biological processes by interacting with a plethora of client proteins. Giardia duodenalis is a flagellated protozoan that affects millions of people worldwide causing an acute and chronic diarrheal disease. The single giardial 14-3-3 isoform (g14-3-3, unique in the 14-3-3 family, needs the constitutive phosphorylation of Thr214 and the polyglycylation of its C-terminus to be fully functional in vivo. Alteration of the phosphorylation and polyglycylation status affects the parasite differentiation into the cyst stage. To further investigate the role of these post-translational modifications, the crystal structure of the g14-3-3 was solved in the unmodified apo form. Oligomers of g14-3-3 were observed due to domain swapping events at the protein C-terminus. The formation of filaments was supported by TEM. Mutational analysis, in combination with native PAGE and chemical cross-linking, proved that polyglycylation prevents oligomerization. In silico phosphorylation and molecular dynamics simulations supported a structural role for the phosphorylation of Thr214 in promoting target binding. Our findings highlight unique structural features of g14-3-3 opening novel perspectives on the evolutionary history of this protein family and envisaging the possibility to develop anti-giardial drugs targeting g14-3-3.

  13. Modified Field's staining--a rapid stain for Trichomonas vaginalis.

    Science.gov (United States)

    Afzan, M Yusuf; Sivanandam, S; Kumar, G Suresh

    2010-10-01

    Trichomonas vaginalis, a flagellate protozoan parasite commonly found in the human genitourinary tract, is transmitted primarily by sexual intercourse. Diagnosis is usually by in vitro culture method and staining with Giemsa stain. There are laboratories that use Gram stain as well. We compared the use of modified Field's (MF), Giemsa, and Gram stains on 2 axenic and xenic isolates of T. vaginalis, respectively. Three smears from every sediment of spun cultures of all 4 isolates were stained, respectively, with each of the stains. We showed that MF staining, apart from being a rapid stain (20 s), confers sharper staining contrast, which differentiates the nucleus and the cytoplasm of the organism when compared to Giemsa and Gram staining especially on parasites from spiked urine samples. The alternative staining procedure offers in a diagnostic setting a rapid stain that can easily visualize the parasite with sharp contrasting characteristics between organelles especially the nucleus and cytoplasm. Vacuoles are more clearly visible in parasites stained with MF than when stained with Giemsa. Copyright © 2010 Elsevier Inc. All rights reserved.

  14. Small scale temporal variability in the phytoplankton of Independencia Bay, Pisco, Perú

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    Noemí Ochoa

    2013-06-01

    Full Text Available Temporal variations at small scale of the coastal marine phytoplankton assemblages were studied. Water samples were collected at a fixed station in Bahia Independencia (Pisco-Peru. The sampling took place in the morning (08:00 h. and afternoon (15:00 h over a period of 29 days (March 28 to April 25, 1988. Surface temperatures also were taken, fluctuating from 15,4 °C to 17,2 °C. Diatoms were the principal component of the phytoplankton community and were more related with the total of phytoplankton. Other groups as Dinoflagellates, Coccolitophorids, Silicoflagellates and small flagellates were present but were less important. Skeletonema costatum was the dominant specie during the first nine days of sampling, after that it was substituted by Thalassionema nitzschioides, which remained as dominant until the end of the study. Small variation in species composition but large fluctuations in density of phytoplankton were recorded over a period of few hours. Small increments in temperature influenced in the phytoplankton assemblages.

  15. Update on pathology of ocular parasitic disease.

    Science.gov (United States)

    Das, Dipankar; Ramachandra, Varsha; Islam, Saidul; Bhattacharjee, Harsha; Biswas, Jyotirmay; Koul, Akanksha; Deka, Panna; Deka, Apurba

    2016-11-01

    Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa) or multicellular (helminths and arthropods). The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

  16. Risk factors associated with Trypanosoma cruzi exposure in domestic dogs from a rural community in Panama.

    Science.gov (United States)

    Saldaña, Azael; Calzada, José E; Pineda, Vanessa; Perea, Milixa; Rigg, Chystrie; González, Kadir; Santamaria, Ana Maria; Gottdenker, Nicole L; Chaves, Luis F

    2015-11-01

    Chagas disease, caused by Trypanosoma cruzi infection, is a zoonosis of humans, wild and domestic mammals, including dogs. In Panama, the main T. cruzi vector is Rhodnius pallescens, a triatomine bug whose main natural habitat is the royal palm, Attalea butyracea. In this paper, we present results from three T. cruzi serological tests (immunochromatographic dipstick, indirect immunofluorescence and ELISA) performed in 51 dogs from 24 houses in Trinidad de Las Minas, western Panama. We found that nine dogs were seropositive (17.6% prevalence). Dogs were 1.6 times more likely to become T. cruzi seropositive with each year of age and 11.6 times if royal palms where present in the peridomiciliary area of the dog's household or its two nearest neighbours. Mouse-baited-adhesive traps were employed to evaluate 12 peridomestic royal palms. All palms were found infested with R. pallescens with an average of 25.50 triatomines captured per palm. Of 35 adult bugs analysed, 88.6% showed protozoa flagellates in their intestinal contents. In addition, dogs were five times more likely to be infected by the presence of an additional domestic animal species in the dog's peridomiciliary environment. Our results suggest that interventions focused on royal palms might reduce the exposure to T. cruzi infection.

  17. The mystery of clade X: Orciraptor gen. nov. and Viridiraptor gen. nov. are highly specialised, algivorous amoeboflagellates (Glissomonadida, Cercozoa).

    Science.gov (United States)

    Hess, Sebastian; Melkonian, Michael

    2013-09-01

    In freshwater ecosystems a vast diversity of elusive protists exists that specifically feed on microalgae. Due to difficulties in isolation and long-term maintenance, most of these are still poorly known. In this study stable, bacteria-free cultures of several limnetic, algivorous amoeboflagellates were investigated by light microscopy and molecular phylogenetic analyses. All strains represent naked, biflagellate cells, either occurring as rigid flagellates or as surface-attached amoebae. They perforate cell walls of certain Zygnematophyceae and Chlorophyceae (Viridiplantae) and phagocytose algal cell contents. Time-lapse microscopy revealed the feeding behaviour, locomotional processes and life histories of the amoeboflagellates. Clear differences in cell morphology and food range specificity led to the description of two new, monotypic genera Orciraptor and Viridiraptor, which occupy similar, but distinct ecological niches in aquatic ecosystems as 'necrophytophagous' and 'parasitoid' protists, respectively. Molecular phylogenetic analyses based on 18S rDNA sequence data demonstrated that Orciraptor and Viridiraptor belonged to 'clade X' within the order Glissomonadida (Cercozoa, Rhizaria). In conclusion, we established the phenotypic identity of a clade, which until now was exclusively known from environmental sequences, and erect the new family Viridiraptoridae for 'clade X'. Its algivorous members are compared with other glissomonads and nomenclatural, methodological and ecological aspects of these novel 'raptorial' amoeboflagellates are discussed. Copyright © 2013 Elsevier GmbH. All rights reserved.

  18. Man-biting sand fly species and natural infection with the Leishmania promastigote in leishmaniasis-endemic areas of Ecuador.

    Science.gov (United States)

    Gomez, Eduardo A; Kato, Hirotomo; Hashiguchi, Yoshihisa

    2014-12-01

    A countrywide surveillance of sand flies was performed to obtain information on their geographical distribution and natural infection by Leishmania protozoa in Ecuador. A total of 18,119 sand flies were collected by human landing collections during 32 years from 1982 to 2014, and 29 species were recognized. The most prevalent 10 species were Lutzomyia gomezi, Lu. robusta, Lu. hartmanni, Lu. shannoni, Lu. trapidoi, Lu. panamensis, Lu. maranonensis, Lu. ayacuchensis, Lu. tortura and Lu. yuilli yuilli, and their topographical and vertical distributions were identified. Among all the sand flies, only 197 (1.09%) flies of four Lutzomyia species, Lu. gomezi, Lu. trapidoi, Lu. tortura and Lu. ayacuchensis, were positive for Leishmania. Endotrypanum, a flagellate parasite not pathogenic to humans, were detected in five Lutzomyia species, Lu. robusta, Lu. hartmanni, Lu. trapidoi, Lu. panamensis and Lu. yuilli yuilli, suggesting wide vector-ranges of Endotrypanum species. These data on the genus Lutzomyia and their natural infections with Leishmania and Endotrypanum will be useful for transmission studies and surveillance of leishmaniasis. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. A Novel Association between Two Trypanosome-Specific Factors and the Conserved L5-5S rRNA Complex

    Science.gov (United States)

    Ciganda, Martin; Prohaska, Kimberly; Hellman, Kristina; Williams, Noreen

    2012-01-01

    P34 and P37 are two previously identified RNA binding proteins in the flagellate protozoan Trypanosoma brucei. RNA interference studies have determined that the proteins are involved in and essential for ribosome biogenesis. The proteins interact with the 5S rRNA with nearly identical binding characteristics. We have shown that this interaction is achieved mainly through the LoopA region of the RNA, but P34 and P37 also protect the L5 binding site located on LoopC. We now provide evidence to show that these factors form a novel pre-ribosomal particle through interactions with both 5S rRNA and the L5 ribosomal protein. Further in silico and in vitro analysis of T. brucei L5 indicates a lower affinity for 5S rRNA than expected, based on other eukaryotic L5 proteins. We hypothesize that P34 and P37 complement L5 and bridge the interaction with 5S rRNA, stabilizing it and aiding in the early steps of ribosome biogenesis. PMID:22859981

  20. Phylogenomic analyses support the monophyly of Excavata and resolve relationships among eukaryotic "supergroups".

    Science.gov (United States)

    Hampl, Vladimir; Hug, Laura; Leigh, Jessica W; Dacks, Joel B; Lang, B Franz; Simpson, Alastair G B; Roger, Andrew J

    2009-03-10

    Nearly all of eukaryotic diversity has been classified into 6 suprakingdom-level groups (supergroups) based on molecular and morphological/cell-biological evidence; these are Opisthokonta, Amoebozoa, Archaeplastida, Rhizaria, Chromalveolata, and Excavata. However, molecular phylogeny has not provided clear evidence that either Chromalveolata or Excavata is monophyletic, nor has it resolved the relationships among the supergroups. To establish the affinities of Excavata, which contains parasites of global importance and organisms regarded previously as primitive eukaryotes, we conducted a phylogenomic analysis of a dataset of 143 proteins and 48 taxa, including 19 excavates. Previous phylogenomic studies have not included all major subgroups of Excavata, and thus have not definitively addressed their interrelationships. The enigmatic flagellate Andalucia is sister to typical jakobids. Jakobids (including Andalucia), Euglenozoa and Heterolobosea form a major clade that we name Discoba. Analyses of the complete dataset group Discoba with the mitochondrion-lacking excavates or "metamonads" (diplomonads, parabasalids, and Preaxostyla), but not with the final excavate group, Malawimonas. This separation likely results from a long-branch attraction artifact. Gradual removal of rapidly-evolving taxa from the dataset leads to moderate bootstrap support (69%) for the monophyly of all Excavata, and 90% support once all metamonads are removed. Most importantly, Excavata robustly emerges between unikonts (Amoebozoa + Opisthokonta) and "megagrouping" of Archaeplastida, Rhizaria, and chromalveolates. Our analyses indicate that Excavata forms a monophyletic suprakingdom-level group that is one of the 3 primary divisions within eukaryotes, along with unikonts and a megagroup of Archaeplastida, Rhizaria, and the chromalveolate lineages.