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G R Shaw - One of the best experts on this subject based on the ideXlab platform.
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first evidence for the production of cylindrospermopsin and deoxy cylindrospermopsin by the freshwater benthic cyanobacterium lyngbya wollei farlow ex gomont speziale and dyck
Harmful Algae, 2007Co-Authors: Mark Seifert, Glenn B Mcgregor, G Eaglesham, W A Wickramasinghe, G R ShawAbstract:Lyngbya wollei (Farlow ex Gomont) Speziale and Dyck is a common mat-forming benthic cyanobacterium from freshwater habitats.We found that two populations from southeast Queensland (Australia) produce the potent cyanotoxin cylindrospermopsin (CYN) and its analogue, deoxy-cylindrospermopsin (deoxy-CYN). The highest concentrations in environmental samples were 20 and 550 mg g1 dry weight for CYN and deoxy-CYN, respectively. A sub-sample maintained in culture for over 16 months yielded concentrations of 33 and 308 mg g1 dry weight for CYN and deoxy-CYN, respectively. The concentration of deoxy-CYN in L. wollei was 10–300 times higher than CYN, suggesting that, unlike many other CYN-producing cyanobacteria, the primary compound produced by L. wollei is deoxy-CYN. The production of CYN and deoxy-CYN by L. wollei represents a potential human health risk and an additional source of these toxins in freshwaters. This is the first report of the production of CYN and deoxy-CYN by L. wollei or any species of the Oscillatoriales.
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first evidence for the production of cylindrospermopsin and deoxy cylindrospermopsin by the freshwater benthic cyanobacterium lyngbya wollei farlow ex gomont speziale and dyck
Harmful Algae, 2007Co-Authors: Mark Seifert, Glenn B Mcgregor, G Eaglesham, W A Wickramasinghe, G R ShawAbstract:Lyngbya wollei (Farlow ex Gomont) Speziale and Dyck is a common mat-forming benthic cyanobacterium from freshwater habitats. We found that two populations from southeast Queensland (Australia) produce the potent cyanotoxin cylindrospermopsin (CYN) and its analogue, deoxy-cylindrospermopsin (deoxy-CYN). The highest concentrations in environmental samples were 20 and 550 m gg � 1 dry weight for CYN and deoxy-CYN, respectively. A sub-sample maintained in culture for over 16 months yielded concentrations of 33 and 308 m gg � 1 dry weight for CYN and deoxy-CYN, respectively. The concentration of deoxy-CYN in L. wollei was 10–300 times higher than CYN, suggesting that, unlike many other CYN-producing cyanobacteria, the primary compound produced byL. wollei is deoxy-CYN. The production of CYN and deoxy-CYN byL. wollei represents a potential human health risk and an additional source of these toxins in freshwaters. This is the first report of the production of CYN and deoxy-CYN by L. wollei or any species of the Oscillatoriales. # 2006 Elsevier B.V. All rights reserved.
Luis Henrique Zanini Branco - One of the best experts on this subject based on the ideXlab platform.
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a widespread cyanobacterium supported by polyphasic approach proposition of koinonema pervagatum gen sp nov Oscillatoriales 1
Journal of Phycology, 2017Co-Authors: Bruna Buch, Mariellen Dornelles Martins, Luis Henrique Zanini BrancoAbstract:Several new genera originally classified as the genus Phormidium, a polyphyletic and taxonomically complex genus within the Oscillatoriales, were recently described. The simple morphology of Phormidium does not reflect its genetic diversity and the delimitation of a natural group is not possible with traditional classification systems based on morphology alone. Therefore, this study used morphological, ecological, and molecular approaches to evaluate four populations morphologically similar to Ammassolinea, Kamptonema, and Ancylothrix (simple, curved, and gradually attenuated at the ends trichome), found in subtropical and tropical Brazilian regions. 16S rRNA gene sequences grouped all the strains in a highly supported clade with other two European strains isolated from thermal springs surrounding areas. The 16S-23S ITS secondary structure corroborated the phylogenetic analysis with all the strains having similar structures. Consequently, a genetically well-defined and cryptic new genus, Koinonema gen. nov., is proposed containing the aquatic, mesophilic, and morphologically homogeneous new species, Koinonema pervagatum sp. nov.
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potamolinea gen nov Oscillatoriales cyanobacteria a phylogenetically and ecologically coherent cyanobacterial genus
International Journal of Systematic and Evolutionary Microbiology, 2016Co-Authors: Mariellen Dornelles Martins, Luis Henrique Zanini BrancoAbstract:Phormidium Kutzing ex Gomont, a common genus of the Cyanobacteria, is widely known as a problematic group. Its simple morphology is not congruent with its genetic heterogeneity and several new generic entities have been described based on 16S rRNA gene sequence analyses from populations with similar morphology. During a study of the diversity of Phormidioideae (Phormidiaceae, Oscillatoriales) in Brazil, ten Phormidium-like strains from south-eastern and mid-western regions were isolated in monospecific cultures and submitted to polyphasic evaluation (morphological, ecological and molecular studies). The populations studied presented homogeneous morphology (trichomes straight, not attenuated and apical cell rounded or obtuse), differing mainly in cell length from the type species of the genus Phormidium (Phormidium lucidum Agardh ex Gomont) and occurring as three morphotypes. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the populations studied, with European Phormidium aerugineo-caeruleum (Gomont) Anagnostidis & Komarek strains, were placed together in a very distinctive and highly supported clade. Thus, the set of characteristics of the strains resulted in the recognition of the new genus Potamolinea Martins et Branco with two species: Potamolinea magna as the type species (strains 47PC and 48PC) and Potamolinea aerugineo-caerulea (Gomont) Martins et Branco (strains 1PC, 2PC and 38PC). These two species plus one still undetermined lineage,Potamolinea sp., are morphologically and genetically distinguishable, whereas the secondary structures of the D1-D1', box-B and V3 regions were conserved within each one. The generic name and specific epithets of the new taxa are proposed under the provisions of the International Code of Nomenclature for algae, fungi and plants.
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phyllonema aviceniicola gen nov sp nov and foliisarcina bertiogensis gen nov sp nov epiphyllic cyanobacteria associated with avicennia schaueriana leaves
International Journal of Systematic and Evolutionary Microbiology, 2016Co-Authors: Danillo Oliveira Alvarenga, Luis Henrique Zanini Branco, Janaina Rigonato, Itamar Soares De Melo, Marli Fatima FioreAbstract:Cyanobacteria dwelling on the salt-excreting leaves of the mangrove tree Avicennia schaueriana were isolated and characterized by ecological, morphological and genetic approaches. Leaves were collected in a mangrove with a history of oil contamination on the coastline of Sao Paulo state, Brazil, and isolation was achieved by smearing leaves on the surface of solid media or by submerging leaves in liquid media. Twenty-nine isolated strains were shown to belong to five cyanobacterial orders (thirteen to Synechococcales, seven to Nostocales, seven to Pleurocapsales, one to Chroococcales, and one to Oscillatoriales) according to morphological and 16S rRNA gene sequence evaluations. More detailed investigations pointed six Rivulariacean and four Xenococcacean strains as novel taxa. These strains were classified as Phyllonema gen. nov. (type species Phyllonema aviceniicola sp. nov. with type strain CENA341T) and Foliisarcina gen. nov. (type species Foliisarcina bertiogensis sp. nov. with type strain CENA333T), according to the International Code of Nomenclature for Algae, Fungi, and Plants. This investigation shows some of the unique cyanobacteria inhabiting the phyllosphere of Avicennia schaueriana can be retrieved by culturing techniques, improving current taxonomy and providing new insights into the evolution, ecology, and biogeography of this phylum.
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aerophytic cyanoprokaryotes from the atlantic rainforest region of sao paulo state brazil chroococcales and Oscillatoriales
Cryptogamie Algologie, 2009Co-Authors: Luis Henrique Zanini Branco, Joana Pozzetti Teixeira, Viviani Ferreira, Lucien Hoffmann, Jose Cesar De Morais FilhoAbstract:Puisque les algues sont principalement aquatiques, il semble presque paradoxal qu'il existe une flore du sol relativement diversifiee ou les cyanoprokaryotes aerophiles sont particulierement abondantes. Cependant, les etudes dans ce domaine ne sont pas tres nombreuses. Le present article se propose de contribuer a la connaissance taxonomique de la flore des cyanoprocaryotes chroococcales et Oscillatoriales dans les regions tropicales. Des echantillons de cyanoprokaryotes ont ete preleves dans une foret ombrophile de l'etat de Sao Paulo, Bresil. Les donnees sur le type et la couleur de la masse des cyanoprokaryotes, le type de substrat, la temperature et l'humidite de la masse et de l'air, le pH et les irradiances absolue et relative ont aussi ete enregistrees. L'etude a montre la presence de 24 especes appartenant aux ordres des Chroococcales et Oscillatoriales (12 especes chacun). Aphanothece (quatre especes) etait le genre le plus riche en especes. En general, la resolution taxonomique sur la base de donnees morphologiques et morphometriques peut parfois demeurer problematique.
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aerophytic cyanoprokaryotes from the atlantic rainforest region of sao paulo state brazil chroococcales and Oscillatoriales
Cryptogamie Algologie, 2009Co-Authors: Luis Henrique Zanini Branco, Joana Pozzetti Teixeira, Viviani Ferreira, Lucien Hoffmann, Jose Cesar De Morais FilhoAbstract:Puisque les algues sont principalement aquatiques, il semble presque paradoxal qu'il existe une flore du sol relativement diversifiee ou les cyanoprokaryotes aerophiles sont particulierement abondantes. Cependant, les etudes dans ce domaine ne sont pas tres nombreuses. Le present article se propose de contribuer a la connaissance taxonomique de la flore des cyanoprocaryotes chroococcales et Oscillatoriales dans les regions tropicales. Des echantillons de cyanoprokaryotes ont ete preleves dans une foret ombrophile de l'etat de Sao Paulo, Bresil. Les donnees sur le type et la couleur de la masse des cyanoprokaryotes, le type de substrat, la temperature et l'humidite de la masse et de l'air, le pH et les irradiances absolue et relative ont aussi ete enregistrees. L'etude a montre la presence de 24 especes appartenant aux ordres des Chroococcales et Oscillatoriales (12 especes chacun). Aphanothece (quatre especes) etait le genre le plus riche en especes. En general, la resolution taxonomique sur la base de donnees morphologiques et morphometriques peut parfois demeurer problematique.
Lothar Krienitz - One of the best experts on this subject based on the ideXlab platform.
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desertifilum fontinale sp nov Oscillatoriales cyanobacteria from a warm spring in east africa based on conventional and molecular studies
Fottea, 2014Co-Authors: Pawan K Dadheech, Huda Mahmoud, Kiplagat Kotut, Lothar KrienitzAbstract:Desertifilum is a filamentous cyanobacterium of crusts and biofilms, recently described from the extreme hot and dry Thar Desert in north-western India. A new species was isolated from a warm spring near Lake Bogoria, Kenya and was characterised by light and electron microscopy and phylogenetically using the 16S rRNA gene, beta and alpha subunits including intergenic spacer (cpcBA-IGS) and 16S-23S internal transcribed spacer (ITS). The aquatic habitat of the new material from Kenya revealed a wider distribution of members of this genus. The new taxon was found to be closest to Desertifilum tharense (Oscillatoriales). The separation of the new species described here as D. fontinale sp. nov., using conventional and molecular traits, was based on differences in phenotypic features, 16S-23S ITS sequence and habitat.
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phormidium etoshii sp nov Oscillatoriales cyanobacteria described from the etosha pan namibia based on morphological molecular and ecological features
Fottea, 2013Co-Authors: Pawan K Dadheech, Dale A Casamatta, Peter Casper, Lothar KrienitzAbstract:An edaphic, filamentous, nonheterocytous cyanobacterium was collected from the Etosha Pan, Namibia. Based on multilocus sequencing of the 16S rRNA gene, beta and alpha subunits (cpcBA-IGS) of the phycocyanin operon and morphological and ecological features, we describe the new species Phormidium etoshii (Oscillatoriales). The taxon was differentiated from the phylogenetically closest taxa in morphological features and ecology.
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polyphasic characterization of cyanobacteria isolated from desert crusts and the description of desertifilum tharense gen et sp nov Oscillatoriales
Phycologia, 2012Co-Authors: Pawan K Dadheech, Raeid M M Abed, Huda Mahmoud, Krishna M Mohan, Lothar KrienitzAbstract:Dadheech P.K., Abed R.M.M., Mahmoud H., Krishna Mohan M. and Krienitz L. 2012. Polyphasic characterization of cyanobacteria isolated from desert crusts, and the description of Desertifilum tharense gen. et sp. nov. (Oscillatoriales) Phycologia 51: 260–270. DOI: 10.2216/09-51.1 Four new cyanobacterial strains isolated from biological desert crusts in Thar Desert, India were characterized using a polyphasic approach. The strains were designated to two mophotypes, but all strains exhibited identical 16S ribosomal RNA (rRNA) gene sequences. On the basis of 16S rRNA phylogenetic reconstruction, the strains belonged to the Oscillatoriales order and formed a coherent cluster in the phylogenetic tree, with more than 5% sequence divergence to the closest relative belonging to a species of Microcoleus Desmazieres ex Gomont. Our strains were different from the genus Microcoleus in phenotypic characters such as organization of thallus, trichome width, cell shape, gas vesicle, thylakoid arrangement and habitat. Althou...
Pawan K Dadheech - One of the best experts on this subject based on the ideXlab platform.
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desertifilum fontinale sp nov Oscillatoriales cyanobacteria from a warm spring in east africa based on conventional and molecular studies
Fottea, 2014Co-Authors: Pawan K Dadheech, Huda Mahmoud, Kiplagat Kotut, Lothar KrienitzAbstract:Desertifilum is a filamentous cyanobacterium of crusts and biofilms, recently described from the extreme hot and dry Thar Desert in north-western India. A new species was isolated from a warm spring near Lake Bogoria, Kenya and was characterised by light and electron microscopy and phylogenetically using the 16S rRNA gene, beta and alpha subunits including intergenic spacer (cpcBA-IGS) and 16S-23S internal transcribed spacer (ITS). The aquatic habitat of the new material from Kenya revealed a wider distribution of members of this genus. The new taxon was found to be closest to Desertifilum tharense (Oscillatoriales). The separation of the new species described here as D. fontinale sp. nov., using conventional and molecular traits, was based on differences in phenotypic features, 16S-23S ITS sequence and habitat.
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phormidium etoshii sp nov Oscillatoriales cyanobacteria described from the etosha pan namibia based on morphological molecular and ecological features
Fottea, 2013Co-Authors: Pawan K Dadheech, Dale A Casamatta, Peter Casper, Lothar KrienitzAbstract:An edaphic, filamentous, nonheterocytous cyanobacterium was collected from the Etosha Pan, Namibia. Based on multilocus sequencing of the 16S rRNA gene, beta and alpha subunits (cpcBA-IGS) of the phycocyanin operon and morphological and ecological features, we describe the new species Phormidium etoshii (Oscillatoriales). The taxon was differentiated from the phylogenetically closest taxa in morphological features and ecology.
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polyphasic characterization of cyanobacteria isolated from desert crusts and the description of desertifilum tharense gen et sp nov Oscillatoriales
Phycologia, 2012Co-Authors: Pawan K Dadheech, Raeid M M Abed, Huda Mahmoud, Krishna M Mohan, Lothar KrienitzAbstract:Dadheech P.K., Abed R.M.M., Mahmoud H., Krishna Mohan M. and Krienitz L. 2012. Polyphasic characterization of cyanobacteria isolated from desert crusts, and the description of Desertifilum tharense gen. et sp. nov. (Oscillatoriales) Phycologia 51: 260–270. DOI: 10.2216/09-51.1 Four new cyanobacterial strains isolated from biological desert crusts in Thar Desert, India were characterized using a polyphasic approach. The strains were designated to two mophotypes, but all strains exhibited identical 16S ribosomal RNA (rRNA) gene sequences. On the basis of 16S rRNA phylogenetic reconstruction, the strains belonged to the Oscillatoriales order and formed a coherent cluster in the phylogenetic tree, with more than 5% sequence divergence to the closest relative belonging to a species of Microcoleus Desmazieres ex Gomont. Our strains were different from the genus Microcoleus in phenotypic characters such as organization of thallus, trichome width, cell shape, gas vesicle, thylakoid arrangement and habitat. Althou...
W A Wickramasinghe - One of the best experts on this subject based on the ideXlab platform.
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first evidence for the production of cylindrospermopsin and deoxy cylindrospermopsin by the freshwater benthic cyanobacterium lyngbya wollei farlow ex gomont speziale and dyck
Harmful Algae, 2007Co-Authors: Mark Seifert, Glenn B Mcgregor, G Eaglesham, W A Wickramasinghe, G R ShawAbstract:Lyngbya wollei (Farlow ex Gomont) Speziale and Dyck is a common mat-forming benthic cyanobacterium from freshwater habitats.We found that two populations from southeast Queensland (Australia) produce the potent cyanotoxin cylindrospermopsin (CYN) and its analogue, deoxy-cylindrospermopsin (deoxy-CYN). The highest concentrations in environmental samples were 20 and 550 mg g1 dry weight for CYN and deoxy-CYN, respectively. A sub-sample maintained in culture for over 16 months yielded concentrations of 33 and 308 mg g1 dry weight for CYN and deoxy-CYN, respectively. The concentration of deoxy-CYN in L. wollei was 10–300 times higher than CYN, suggesting that, unlike many other CYN-producing cyanobacteria, the primary compound produced by L. wollei is deoxy-CYN. The production of CYN and deoxy-CYN by L. wollei represents a potential human health risk and an additional source of these toxins in freshwaters. This is the first report of the production of CYN and deoxy-CYN by L. wollei or any species of the Oscillatoriales.
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first evidence for the production of cylindrospermopsin and deoxy cylindrospermopsin by the freshwater benthic cyanobacterium lyngbya wollei farlow ex gomont speziale and dyck
Harmful Algae, 2007Co-Authors: Mark Seifert, Glenn B Mcgregor, G Eaglesham, W A Wickramasinghe, G R ShawAbstract:Lyngbya wollei (Farlow ex Gomont) Speziale and Dyck is a common mat-forming benthic cyanobacterium from freshwater habitats. We found that two populations from southeast Queensland (Australia) produce the potent cyanotoxin cylindrospermopsin (CYN) and its analogue, deoxy-cylindrospermopsin (deoxy-CYN). The highest concentrations in environmental samples were 20 and 550 m gg � 1 dry weight for CYN and deoxy-CYN, respectively. A sub-sample maintained in culture for over 16 months yielded concentrations of 33 and 308 m gg � 1 dry weight for CYN and deoxy-CYN, respectively. The concentration of deoxy-CYN in L. wollei was 10–300 times higher than CYN, suggesting that, unlike many other CYN-producing cyanobacteria, the primary compound produced byL. wollei is deoxy-CYN. The production of CYN and deoxy-CYN byL. wollei represents a potential human health risk and an additional source of these toxins in freshwaters. This is the first report of the production of CYN and deoxy-CYN by L. wollei or any species of the Oscillatoriales. # 2006 Elsevier B.V. All rights reserved.