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Attheya

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Feixue Fu – 1st expert on this subject based on the ideXlab platform

  • CO_2 and vitamin B_12 interactions determine bioactive trace metal requirements of a subarctic Pacific diatom
    The ISME Journal, 2011
    Co-Authors: Andrew L King, Sergio A Sañudo-wilhelmy, Karine Leblanc, David A Hutchins, Feixue Fu

    Abstract:

    Phytoplankton growth can be limited by numerous inorganic nutrients and organic growth factors. Using the subarctic diatom Attheya sp. in culture studies, we examined how the availability of vitamin B_12 and carbon dioxide partial pressure (pCO_2) influences growth rate, primary productivity, cellular iron (Fe), cobalt (Co), zinc (Zn) and cadmium (Cd) quotas, and the net use efficiencies (NUEs) of these bioactive trace metals (mol C fixed per mol cellular trace metal per day). Under B_12-replete conditions, cells grown at high pCO_2 had lower Fe, Zn and Cd quotas, and used those trace metals more efficiently in comparison with cells grown at low pCO_2. At high pCO_2, B_12-limited cells had ∼50% lower specific growth and carbon fixation rates, and used Fe ∼15-fold less efficiently, and Zn and Cd ∼3-fold less efficiently, in comparison with B_12-replete cells. The observed higher Fe, Zn and Cd NUE under high pCO_2/B_12-replete conditions are consistent with predicted downregulation of carbon-concentrating mechanisms. Co quotas of B_12-replete cells were ∼5- to 14-fold higher in comparison with B_12-limited cells, suggesting that >80% of cellular Co of B_12-limited cells was likely from B_12. Our results demonstrate that CO_2 and vitamin B_12 interactively influence growth, carbon fixation, trace metal requirements and trace metal NUE of this diatom. This suggests the need to consider complex feedback interactions between multiple environmental factors for this biogeochemically critical group of phytoplankton in the last glacial maximum as well as the current and future changing ocean.

  • CO2 and vitamin B12 interactions determine bioactive trace metal requirements of a subarctic Pacific diatom
    The ISME Journal, 2011
    Co-Authors: Andrew L King, Sergio A Sañudo-wilhelmy, Karine Leblanc, David A Hutchins, Feixue Fu

    Abstract:

    Phytoplankton growth can be limited by numerous inorganic nutrients and organic growth factors. Using the subarctic diatom Attheya sp. in culture studies, we examined how the availability of vitamin B-12 and carbon dioxide partial pressure (pCO(2)) influences growth rate, primary productivity, cellular iron (Fe), cobalt (Co), zinc (Zn) and cadmium (Cd) quotas, and the net use efficiencies (NUEs) of these bioactive trace metals (mol C fixed per mol cellular trace metal per day). Under B-12-replete conditions, cells grown at high pCO(2) had lower Fe, Zn and Cd quotas, and used those trace metals more efficiently in comparison with cells grown at low pCO(2). At high pCO(2), B-12-limited cells had similar to 50% lower specific growth and carbon fixation rates, and used Fe similar to 15-fold less efficiently, and Zn and Cd similar to 3-fold less efficiently, in comparison with B-12-replete cells. The observed higher Fe, Zn and Cd NUE under high pCO(2)/B-12-replete conditions are consistent with predicted downregulation of carbon-concentrating mechanisms. Co quotas of B-12-replete cells were similar to 5- to 14-fold higher in comparison with B-12-limited cells, suggesting that >80% of cellular Co of B-12-limited cells was likely from B-12. Our results demonstrate that CO2 and vitamin B-12 interactively influence growth, carbon fixation, trace metal requirements and trace metal NUE of this diatom. This suggests the need to consider complex feedback interactions between multiple environmental factors for this biogeochemically critical group of phytoplankton in the last glacial maximum as well as the current and future changing ocean. The ISME Journal (2011) 5, 1388-1396; doi: 10.1038/ismej.2010.211; published online 20 January 2011

I V Stonik – 2nd expert on this subject based on the ideXlab platform

  • Sterols and Fatty Acids from Attheya Planktonic Diatoms
    Chemistry of Natural Compounds, 2017
    Co-Authors: I V Stonik, N. A. Aizdaicher, I. I. Kapustina, V. I. Svetashev

    Abstract:

    Sterols and fatty-acids isolated from laboratory cultures of the diatoms Attheya decora, A. arenicola, and A. longicornis were studied. The studied cultures of these species were substantially different with respect to the quantitative contents of polyunsaturated fatty acids and sterols. Rare sterols were found in several strains. It was shown that A. arenicola contained primarily 24-ethylcholesterol; A. longicornis and A. decora, 24-ethylcholesterol, 24-methylcholesterol, fucosterol, and 24-methylenecholesterol. Such differences indicate that the genus comprises various groups of species, the phylogenetic positions of which need to be defined.

  • The species composition, morphology, and seasonal distribution of diatoms of the genus Attheya West, 1860 from the Sea of Japan
    Russian Journal of Marine Biology, 2016
    Co-Authors: I V Stonik, N. A. Aizdaicher

    Abstract:

    Six species that belong to the diatom genus Attheya were found in the Russian waters of the Sea of Japan. A. cf. flexuosa is a new record for the seas of Russia. A. decora is recorded for the first time for the Sea of Japan. The peculiarities of the morphology of A. decora and A . cf. flexuosa are described and illustrated. The study of the seasonal distribution, abundance, and ecology of Attheya species in the northwestern Sea of Japan showed that A. longicornis and A. ussurensis were the most numerous and widespread species, reaching maximum densities (up to 1.5 × 10^6 and 1.8 × 10^4 cells/liter, respectively) in the spring, summer, and fall. A . cf. flexuosa and A. septentrionalis were rare and were found in low numbers in the winter and early spring. Based on the ultrastructure of the girdle bands, the form and number of chloroplasts, the presence/absence of rimoportula on the valve, and habitat features, we distinguished two groups of species of the genus Attheya from the Sea of Japan. The first group includes psammophytes A. decora, A. arenicola , and A. ussurensis ; the second one comprises A. longicornis and A . cf. flexuosa epiphytic on other diatoms, as well as A. septentrionalis , which is found in the under-ice plankton and is able to attach to the underside of ice.

  • The morphology, development, and state of the photosynthetic apparatus of the diatom Attheya ussurensis Stonik, Orlova et Crawford, 2006 (Bacillariophyta) in long-term culture
    Russian Journal of Marine Biology, 2011
    Co-Authors: T. Yu. Orlova, I V Stonik, N. A. Aizdaicher, O. G. Schevchenko, S. I. Pogosyan

    Abstract:

    The development of the marine benthic diatom Attheya ussurensis (Bacillariophyta) isolated from Ussuriisky Bay (Sea of Japan) was examined in laboratory culture. It was found that the development of A. ussurensis was characterized by a short lag phase or its absence and high growth rates (about 1.7 divisions per day) during the exponential phase. Resting cells were formed during the stationary growth phase. Morphological and ultrastructural changes in the cells of A. ussurensis during its life cycle are described based on light and electron microscopic observations. Resting cells retained their photosynthetic activity when stored in the dark for a long period of time (up to 1 year) at a temperature of 4–6°C. After 30, 60, 90, 120, 150, and 180 days of storage under such conditions, the culture of A. ussurensis was capable of regeneration due to the existence of the resting cell stage in the life cycle of the microalga.

N. A. Aizdaicher – 3rd expert on this subject based on the ideXlab platform

  • Sterols and Fatty Acids from Attheya Planktonic Diatoms
    Chemistry of Natural Compounds, 2017
    Co-Authors: I V Stonik, N. A. Aizdaicher, I. I. Kapustina, V. I. Svetashev

    Abstract:

    Sterols and fatty-acids isolated from laboratory cultures of the diatoms Attheya decora, A. arenicola, and A. longicornis were studied. The studied cultures of these species were substantially different with respect to the quantitative contents of polyunsaturated fatty acids and sterols. Rare sterols were found in several strains. It was shown that A. arenicola contained primarily 24-ethylcholesterol; A. longicornis and A. decora, 24-ethylcholesterol, 24-methylcholesterol, fucosterol, and 24-methylenecholesterol. Such differences indicate that the genus comprises various groups of species, the phylogenetic positions of which need to be defined.

  • The species composition, morphology, and seasonal distribution of diatoms of the genus Attheya West, 1860 from the Sea of Japan
    Russian Journal of Marine Biology, 2016
    Co-Authors: I V Stonik, N. A. Aizdaicher

    Abstract:

    Six species that belong to the diatom genus Attheya were found in the Russian waters of the Sea of Japan. A. cf. flexuosa is a new record for the seas of Russia. A. decora is recorded for the first time for the Sea of Japan. The peculiarities of the morphology of A. decora and A . cf. flexuosa are described and illustrated. The study of the seasonal distribution, abundance, and ecology of Attheya species in the northwestern Sea of Japan showed that A. longicornis and A. ussurensis were the most numerous and widespread species, reaching maximum densities (up to 1.5 × 10^6 and 1.8 × 10^4 cells/liter, respectively) in the spring, summer, and fall. A . cf. flexuosa and A. septentrionalis were rare and were found in low numbers in the winter and early spring. Based on the ultrastructure of the girdle bands, the form and number of chloroplasts, the presence/absence of rimoportula on the valve, and habitat features, we distinguished two groups of species of the genus Attheya from the Sea of Japan. The first group includes psammophytes A. decora, A. arenicola , and A. ussurensis ; the second one comprises A. longicornis and A . cf. flexuosa epiphytic on other diatoms, as well as A. septentrionalis , which is found in the under-ice plankton and is able to attach to the underside of ice.

  • The morphology, development, and state of the photosynthetic apparatus of the diatom Attheya ussurensis Stonik, Orlova et Crawford, 2006 (Bacillariophyta) in long-term culture
    Russian Journal of Marine Biology, 2011
    Co-Authors: T. Yu. Orlova, I V Stonik, N. A. Aizdaicher, O. G. Schevchenko, S. I. Pogosyan

    Abstract:

    The development of the marine benthic diatom Attheya ussurensis (Bacillariophyta) isolated from Ussuriisky Bay (Sea of Japan) was examined in laboratory culture. It was found that the development of A. ussurensis was characterized by a short lag phase or its absence and high growth rates (about 1.7 divisions per day) during the exponential phase. Resting cells were formed during the stationary growth phase. Morphological and ultrastructural changes in the cells of A. ussurensis during its life cycle are described based on light and electron microscopic observations. Resting cells retained their photosynthetic activity when stored in the dark for a long period of time (up to 1 year) at a temperature of 4–6°C. After 30, 60, 90, 120, 150, and 180 days of storage under such conditions, the culture of A. ussurensis was capable of regeneration due to the existence of the resting cell stage in the life cycle of the microalga.