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Dieter Hanelt - One of the best experts on this subject based on the ideXlab platform.
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ultrastructure of Cosmarium strains zygnematophyceae streptophyta collected from various geographic locations shows species specific differences both at optimal and stress temperatures
Protoplasma, 2014Co-Authors: Marija Stamenkovic, Elke Woelken, Dieter HaneltAbstract:Plant species collected from various climatic zones and stressed in vitro at various temperatures reveal changes in cellular ultrastructure which are in accordance with the climate at their sampling sites. This observation initiated the investigation to establish if stress at different temperatures may cause diverse extents of changes in the ultrastructure of microalgal strains originating from different geographic zones. The study revealed that the six Cosmarium strains demonstrated ultrastructural characteristics that were consistent with their source location under optimal, low and high temperature conditions, pointing to their preference to specific climatic niches. Interestingly, chloroplasts of all of the Cosmarium strains correspond to a sun-adapted type, which is concomitant with earlier statements that these strains are rendered as high-light adapted algae. The Cosmarium strains developed multiple ultrastructural responses which enabled them to cope with excessive temperatures, occasionally occurring in desmid natural habitats. The appearance of cubic membranes and increased number of plastoglobules may represent the first line in protection against high-temperature stress, which is accompanied by the alteration of protein synthesis and the appearance of stress granules in order to preserve cell homeostasis. However, the prolonged warm- or cold-temperature stress obviously initiated the programmed cell death, as concluded from the appearance of several ultrastructural features observed in all of the Cosmarium strains. The fair acclimation possibilities and the ability to undergo programmed cell death in order to save the population, certainly favor the cosmopolitan distribution of the genus Cosmarium.
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xanthophyll cycle pool size and composition in several Cosmarium strains zygnematophyceae streptophyta are related to their geographic distribution patterns
Protist, 2014Co-Authors: Marija Stamenkovic, Kai Bischof, Dieter HaneltAbstract:The photosynthetic behaviour and composition of photosynthetic pigments of four Cosmarium strains collected from different geographic areas were examined under moderate and photoinhibitory white light by means of PAM fluorometry and high-performance liquid chromatography. Generally, all of the Cosmarium strains displayed the photosynthetic performance and the composition of xanthophyll cycle pigments corresponding to that of high-light adapted plants and algae, when grown under the standard laboratory conditions. However, photoinhibitory treatments provoked several strain- and species-specific characteristics despite the long-term cultivation in laboratory conditions. The typical arctic taxon, C. crenatum var. boldtianum, displayed an incomplete violaxanthin cycle yielding an accumulation of antheraxanthin during high light stress, which is considered as an adaptation to occasional high irradiances in the polar zone due to the albedo. So far, the violaxanthin/antheraxanthin turnover was known only in some prasinophycean algae. Antheraxanthin actively participated in the heat dissipation from PSII centres in C. crenatum, as concluded from a significant positive correlation between non-photochemical quenching (NPQ) and the quantity of antheraxanthin. In contrast, all the other Cosmarium strains displayed a complete violaxanthin de-epoxidase action during the high light treatments, as judged from the relatively high production of zeaxanthin which participated in thermal dissipation of excess energy.
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protection strategies of Cosmarium strains zygnematophyceae streptophyta isolated from various geographic regions against excessive photosynthetically active radiation
Photochemistry and Photobiology, 2013Co-Authors: Marija Stamenkovic, Dieter HaneltAbstract:Numerous in vitro investigations have suggested that macroalgae exhibit regular geographic and depth distribution patterns in accordance with the light and temperature predominance at their habitats; however, there have been only a few similar studies concerning microalgae. We examined the potential influence of irradiance on patterns of distribution of four Cosmarium strains isolated from various climatic zones and cultured long term (>15 years) under a constant temperature-light regime. All the Cosmarium strains demonstrated physiological responses that were consistent with the light intensity prevailing at their source location, confirming that these responses are genetically preserved, as concluded from chlorophyll fluorescence and oxygen evolution rates measurements. Addition of inhibitors of chloroplast-encoded protein synthesis (chloramphenicol and streptomycin) and violaxanthin de-epoxidase (dithiothreitol) indicated that the Cosmarium strains developed "sun- or shade-plant" protection strategies, in accordance with the climate at their sampling sites. The polar Cosmarium strains exhibited a "shade-plant strategy"-to suffer some photoinhibition, but acquire increasing protection from photoinhibited PSII centers, whereas the tropical strains displayed a "sun-plant strategy"-to counteract photoinhibition of PSII by a high rate of repair of photoinhibited PSII reaction centers and a high xanthophyll cycle turnover.
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adaptation of growth and photosynthesis to certain temperature regimes is an indicator for the geographical distribution of Cosmarium strains zygnematophyceae streptophyta
European Journal of Phycology, 2013Co-Authors: Marija Stamenkovic, Dieter HaneltAbstract:In contrast to the many investigations on possible relationships between climate and geographical distributions in macroalgae, there are almost no similar studies regarding microalgae. In this study we consider the potential influence of temperature on patterns of distribution of six Cosmarium strains isolated from various climate zones that have been cultured long-term (> 15 years) in a relatively low temperature–low light regime. Growth and photosynthetic parameters, obtained from PAM fluorometry, were used to estimate the physiological characteristics of the strains during and after various temperature treatments. Acclimation to constant temperature and light conditions tended to affect photosynthetic parameters more than algal growth characteristics. However, all of the Cosmarium strains demonstrated physiological responses that were consistent with their source location under both low and high temperature conditions, confirming that such responses are genetically preserved. The Cosmarium strains disp...
Peter F. M. Coesel - One of the best experts on this subject based on the ideXlab platform.
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Taxonomic notes on desmids from the Netherlands III, with a description of five new species
Phytotaxa, 2020Co-Authors: Marien Van Westen, Peter F. M. CoeselAbstract:From the Netherlands, five desmid species are described as new to science: Cosmarium arcuatiporosum, Cosmarium logiensiforme, Cosmarium mandosii, Euastrum neogutwinskii and Euastrum dubioides. Furthermore, Euastrum binale var. tumoriferum is raised to species level with the name Euastrum tumoriferum. The affinity with similarly looking taxa is discussed.
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Taxonomic notes on desmids from the Netherlands II, with a description of six new species
Phytotaxa, 2018Co-Authors: Marien Van Westen, Peter F. M. CoeselAbstract:From the Netherlands, six desmid species are described as new to science: Closterium joostenii, Cosmarium abbreviatiforme, Cosmarium kouwetsii, Cosmarium spierense, Staurastrum exlooënse, and Staurastrum subcomptum. Furthermore, Closterium archerianum var. pseudocynthia is raised to species level with the name Closterium cynthiaforme. The affinity with similarly looking taxa is discussed.
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Taxonomic notes on desmids from the Netherlands II, with a description of six new species
Phytotaxa, 2018Co-Authors: Marien Van Westen, Peter F. M. CoeselAbstract:From the Netherlands, six desmid species are described as new to science: Closterium joostenii , Cosmarium abbreviatiforme, Cosmarium kouwetsii , Cosmarium spierense , Staurastrum exlooense, and Staurastrum subcomptum . Furthermore, Closterium archerianum var. pseudocynthia is raised to species level with the name Closterium cynthiaforme . The affinity with similarly looking taxa is discussed.
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Remarkable desmid species from the southern Patagonian highlands
Fottea, 2017Co-Authors: Peter F. M. Coesel, Sol Porcel, Alfred Van Geest, Irina IzaguirreAbstract:Phytoplankton research in a number of shallow lakes in southern Patagonia revealed the occurrence of three noteworthy Cosmarium species. One of them, Cosmarium decussare Brook et Williamson, found only once before in Antarctica, is remarkable for its highly asymmetric cell morphology. The other two species, Cosmarium chapuense and Cosmarium mickeyoides, striking by an unusual cell shape, are described as new to science. Ecological and biogeographical characteristics are discussed.
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Taxonomic notes on Dutch desmids VII (new species, new names, new record)
Phytotaxa, 2015Co-Authors: Peter F. M. Coesel, Koos MeestersAbstract:From the Netherlands, Cosmarium bipyrenoideum and Euastrum spondylosioides were described as new to science. Cosmarium laeve var. distentum was raised to Cosmarium distentum , whereas Cosmarium cataractarum was newly reported for the Dutch flora. All four species were discussed for possible affiliations with other desmid taxa.
Marija Stamenkovic - One of the best experts on this subject based on the ideXlab platform.
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ultrastructure of Cosmarium strains zygnematophyceae streptophyta collected from various geographic locations shows species specific differences both at optimal and stress temperatures
Protoplasma, 2014Co-Authors: Marija Stamenkovic, Elke Woelken, Dieter HaneltAbstract:Plant species collected from various climatic zones and stressed in vitro at various temperatures reveal changes in cellular ultrastructure which are in accordance with the climate at their sampling sites. This observation initiated the investigation to establish if stress at different temperatures may cause diverse extents of changes in the ultrastructure of microalgal strains originating from different geographic zones. The study revealed that the six Cosmarium strains demonstrated ultrastructural characteristics that were consistent with their source location under optimal, low and high temperature conditions, pointing to their preference to specific climatic niches. Interestingly, chloroplasts of all of the Cosmarium strains correspond to a sun-adapted type, which is concomitant with earlier statements that these strains are rendered as high-light adapted algae. The Cosmarium strains developed multiple ultrastructural responses which enabled them to cope with excessive temperatures, occasionally occurring in desmid natural habitats. The appearance of cubic membranes and increased number of plastoglobules may represent the first line in protection against high-temperature stress, which is accompanied by the alteration of protein synthesis and the appearance of stress granules in order to preserve cell homeostasis. However, the prolonged warm- or cold-temperature stress obviously initiated the programmed cell death, as concluded from the appearance of several ultrastructural features observed in all of the Cosmarium strains. The fair acclimation possibilities and the ability to undergo programmed cell death in order to save the population, certainly favor the cosmopolitan distribution of the genus Cosmarium.
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xanthophyll cycle pool size and composition in several Cosmarium strains zygnematophyceae streptophyta are related to their geographic distribution patterns
Protist, 2014Co-Authors: Marija Stamenkovic, Kai Bischof, Dieter HaneltAbstract:The photosynthetic behaviour and composition of photosynthetic pigments of four Cosmarium strains collected from different geographic areas were examined under moderate and photoinhibitory white light by means of PAM fluorometry and high-performance liquid chromatography. Generally, all of the Cosmarium strains displayed the photosynthetic performance and the composition of xanthophyll cycle pigments corresponding to that of high-light adapted plants and algae, when grown under the standard laboratory conditions. However, photoinhibitory treatments provoked several strain- and species-specific characteristics despite the long-term cultivation in laboratory conditions. The typical arctic taxon, C. crenatum var. boldtianum, displayed an incomplete violaxanthin cycle yielding an accumulation of antheraxanthin during high light stress, which is considered as an adaptation to occasional high irradiances in the polar zone due to the albedo. So far, the violaxanthin/antheraxanthin turnover was known only in some prasinophycean algae. Antheraxanthin actively participated in the heat dissipation from PSII centres in C. crenatum, as concluded from a significant positive correlation between non-photochemical quenching (NPQ) and the quantity of antheraxanthin. In contrast, all the other Cosmarium strains displayed a complete violaxanthin de-epoxidase action during the high light treatments, as judged from the relatively high production of zeaxanthin which participated in thermal dissipation of excess energy.
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protection strategies of Cosmarium strains zygnematophyceae streptophyta isolated from various geographic regions against excessive photosynthetically active radiation
Photochemistry and Photobiology, 2013Co-Authors: Marija Stamenkovic, Dieter HaneltAbstract:Numerous in vitro investigations have suggested that macroalgae exhibit regular geographic and depth distribution patterns in accordance with the light and temperature predominance at their habitats; however, there have been only a few similar studies concerning microalgae. We examined the potential influence of irradiance on patterns of distribution of four Cosmarium strains isolated from various climatic zones and cultured long term (>15 years) under a constant temperature-light regime. All the Cosmarium strains demonstrated physiological responses that were consistent with the light intensity prevailing at their source location, confirming that these responses are genetically preserved, as concluded from chlorophyll fluorescence and oxygen evolution rates measurements. Addition of inhibitors of chloroplast-encoded protein synthesis (chloramphenicol and streptomycin) and violaxanthin de-epoxidase (dithiothreitol) indicated that the Cosmarium strains developed "sun- or shade-plant" protection strategies, in accordance with the climate at their sampling sites. The polar Cosmarium strains exhibited a "shade-plant strategy"-to suffer some photoinhibition, but acquire increasing protection from photoinhibited PSII centers, whereas the tropical strains displayed a "sun-plant strategy"-to counteract photoinhibition of PSII by a high rate of repair of photoinhibited PSII reaction centers and a high xanthophyll cycle turnover.
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adaptation of growth and photosynthesis to certain temperature regimes is an indicator for the geographical distribution of Cosmarium strains zygnematophyceae streptophyta
European Journal of Phycology, 2013Co-Authors: Marija Stamenkovic, Dieter HaneltAbstract:In contrast to the many investigations on possible relationships between climate and geographical distributions in macroalgae, there are almost no similar studies regarding microalgae. In this study we consider the potential influence of temperature on patterns of distribution of six Cosmarium strains isolated from various climate zones that have been cultured long-term (> 15 years) in a relatively low temperature–low light regime. Growth and photosynthetic parameters, obtained from PAM fluorometry, were used to estimate the physiological characteristics of the strains during and after various temperature treatments. Acclimation to constant temperature and light conditions tended to affect photosynthetic parameters more than algal growth characteristics. However, all of the Cosmarium strains demonstrated physiological responses that were consistent with their source location under both low and high temperature conditions, confirming that such responses are genetically preserved. The Cosmarium strains disp...
A. F. Luknitskaya - One of the best experts on this subject based on the ideXlab platform.
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To the flora of сonjugates (Streptophyta, Conjugatophyceae) of the Valdai District area of the National Park «Valdaiskiy» (Novgorod Region, Russia)
Novosti sistematiki nizshikh rastenii, 2014Co-Authors: A. F. LuknitskayaAbstract:76 species, 3 varieties and 1 form from 21 genera of Streptophyta, Conjugatophyceae (Actinotaenium, Bambusina, Closterium, Cosmarium, Cylindrocystis, Euastrum, Gonatozygon, Haplotaenium, Micrasterias, Mougeotia, Netrium, Penium, Planotaenium, Pleurotaenium, Raphidiastrum, Spirogyra, Spirotaenia, Staurastrum, Staurodesmus, Tetmemorus, Xanthidium) were found in the basins of the Valdai District area of the National Park «Valdaiskiy» (Novgorod Region, Russia). The list of species is annotated with data on the species distribution in 55 collecting sites of 29 water bodies of the national park, and species abundance in collected samples according to Luknitskaya (2009). Among above mentioned genera, the genus Cosmarium is represented by the greatest number of species (20). Staurastrum chaetoceros has been found for the first time for the Novgorod Region.
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To the flora of Zygnematophyceae (Streptophyta) of Valdaiskoe Lake (Novgorod Region, Russia)
Novosti sistematiki nizshikh rastenii, 2013Co-Authors: A. F. LuknitskayaAbstract:49 species and 2 varietas from 11 genera of Streptophyta, Zygnematophyceae (Closterium, Cosmarium, Cosmoastrum, Euastrum, Micrasterias, Mougeotia, Pleurotaenium, Raphidiastrum, Spirogyra, Staurastrum, Staurodesmus) were found in Valdaiskoe Lake (National Park «Valdaisky», Novgorod Region, Russia). Leading genus is Cosmarium (23 species).
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The additional data for the flora of conjugates (Streptophyta, Zygnematophyceae) of Mshinskaya Wetland System (Leningrad Region)
Novosti sistematiki nizshikh rastenii, 2012Co-Authors: A. F. LuknitskayaAbstract:51 species from 18 genera of Streptophyta, Zygnematophyceae (Actinotaenium, Bambusina, Closterium, Cylindrocystis, Cosmarium, Cosmoastrum, Docidium, Euastrum, Micrasterias, Mougeotia, Netrium, Pleurotaenium, Raphidiastrum, Spirogyra, Staurastrum, Staurodesmus, Tetmemorus, Xanthidium) were found in Mshinskaya Wetland System (Leningrad Region, Russia). Leading genera are Cosmarium (10 species), Closterium (10), Staurastrum (8 species).
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Preliminary data to the flora of conjugates (Streptophyta, Zygnematophyceae) of Mshinskoye Bog System (Leningrad Region)
Novosti sistematiki nizshikh rastenii, 2011Co-Authors: A. F. LuknitskayaAbstract:73 species and varieties from 15 genera of Streptophyta, Zygnematophyceae (Actinotaenium, Closterium, Cylindrocystis, Cosmarium, Cosmoastrum, Desmidium, Euastrum, Gonatozygon, Mougeotia, Netrium, Pleurotaenium, Spirogyra, Spondylosium, Staurastrum, Staurodesmus) were found in Mshinskoye Bog System (Leningrad Region, Russia). Cosmarium (17 species), Closterium (16), Euastrum (8 species) are leading genera.
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Additions to the flora of algae (Streptophyta, Zygnematophyceae) of Sebezhsky National Park (Pskov Region, Russia)
Novosti sistematiki nizshikh rastenii, 2009Co-Authors: A. F. LuknitskayaAbstract:120 species and varieties from 21 genera of Streptophyta, Zygnematophyceae were found in the “Sebezhsky” National Park (Pskov Region, Russia) in 2005–2007. Leading genera are Cosmarium (34 species), Staurastrum (19 species) and Closterium (14 species).
Okmin Lee - One of the best experts on this subject based on the ideXlab platform.
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Additions to the six taxa of the genus Cosmarium (Desmidiaceae, Charophyta) in Korea
Journal of Ecology and Environment, 2015Co-Authors: Okmin LeeAbstract:Abstract The samples were collected at lowland swamps, reservoirs, mountainous wetlands, and sphagnum bogs from 2012 to 2014. The followings were newly recorded in Korea: two species, three varieties, and one form, including six taxa of the genus Cosmarium. The newly recorded Korean species were Cosmarium bioculatum var. hians , C. bireme , C. pseudobire -mum, C. nitidulum var. pseudorectangulare, C. trilobulatum f. retusum , and C. trilobulatum var. depressum . The flora of the genus Cosmarium contains 303 taxa in total in Korea. The specimens were cultured and deposited on the algal culture collection of Kyonggi University (ACKU) and National Institute of Botanical Resources (NIBR). Key words: flora, freshwater algae, genus Cosmarium , newly recorded species of Korea INTRODUCTION Desmids, which are exclusively freshwater algae, at-tracted the attention of early microscopists due to their forms. In particular, they exhibit great diversity in their external morphology and show a remarkably complex cell symmetry. As consequence of their diversity, more than 6,000 species have been described from fresh water in all parts of the world (Brook 1981).
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molecular phylogeny of the genera staurastrum and staurodesmus zygnematophyceae streptophyta based on nuclear 18s rdna and chloroplast gene atpb sequences
Algae, 2007Co-Authors: Byeongryeol Moon, Okmin LeeAbstract:To gain insights into the phylogenetic relationships of genus Staurastrum and Staurodesmus, we analyzed nuclearencoded small subunit rDNA of 82 strains, and chloroplast atpB gene sequences of 44 strains belonging to three genera (Staurastrum, Staurodesmus, Cosmarium). Excluding the Staurastrum muticum and S. orbiculare, forty five strains of genus Staurastrum formed a well supported clade. It was shown that with no cell wall sculpture and processes, these two species have a strong phylogenetic relationship with genus Staurodesmus. Therefore, it is strongly recommended to transfer Staurastrum without processes and cell wall sculpture into Staurodesmus. S. obsoletus is a taxa that is transferred from Cosmarium. But, from this study, it has shown a phylogenetic relationship with Cosmarium. Therefore, this species is strongly recommended to transfer back to Cosmarium instead of Staurodesmus. As it was studied before, genus Staurastrum has shown monophyletic. Since the genus taurodesmus groups with Cosmarium, they were shown to be polyphyletic.
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an addition of 6 taxa of the genus Cosmarium chlorophyta in korea
Algae, 2004Co-Authors: Junghoon Park, Okmin LeeAbstract:Six taxa of unrecorded Korean species of genus Cosmarium were collected from several freshwater sites of South Korea in 2003. They were 3 species and 3 varieties of Genus Cosmarium. Genus Cosmarium of Korea was reported to totally 273 taxa 125 species, 113 varieties and 35 forms including this study.
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a phylogenetic significance of several species from genus Cosmarium chlorophyta of korea based on mitochondrial coxiii gene sequences
Algae, 2003Co-Authors: Byeongryeol Mun, Okmin LeeAbstract:It has been considered that genus Cosmarium including Staurastrum had the problems in grouping by morphological characters. Sequence data for the Cytochrome Oxidase subunit III (coxIII) were employed to compare with taxa of two divisions of this genus, with sections in each, for evaluating the taxonomic stability of these morphological characters. The division and section systems were not coincided with the phylogeny inferred from coxIII sequences, as the previous reports from us using nuclear rDNA ITS and chloroplast rbcL sequence comparisons in this genus. Two taxa of Staurastrum were not placed within a same clade each other, and one taxon of these was grouped in Arthrodesmus clade. Two genera, Cosmarium and Staurastrum, cannot be regarded as monophyletic from this result. Mitochondrial coxIII gene was considered as a useful phylogenetic tool to evaluate evolutionary relationships of desmids as in the case of land plants.耀Ѐက
