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James L Wee - One of the best experts on this subject based on the ideXlab platform.
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Silica-scaled chrysophytes and synurophytes from East Texas
Texas Journal of Science, 2002Co-Authors: De Wujek, James L Wee, James E. Van KleyAbstract:A total of 27 scale-bearing species of the algal classes Chrysophyceae and Synurophyceae, referred to herein as scaled chrysophytes, were recorded in 35 water bodies from 11 eastern Texas counties using transmission electron microscopy. These were distributed between the Chrysophyceae (one Chrysosphaerella sp., one Paraphysomonas sp. and two Spiniferomonas sp.) and Synurophyceae (14 Mallomonas sp. and nine Synura sp.). The number of taxa per collection varied from zero to six. Twenty-three taxa are new records for Texas. Mallomonas multisetigera is reported for the first time from North America. Scales of the colorless free-living flagellate Gyromitus disomatus, an organism of uncertain taxonomic affinity, were also observed.
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a reassessment of its 5 8s dna sequence variation and phylogenetic signal in the Synurophyceae
Journal of Phycology, 2000Co-Authors: James L WeeAbstract:Previously, DNA sequences were determined for the entire ITS/5.8S region by direct sequencing of PCR amplification products. 28 sequences were obtained from 12 species of Synurophyceae, including Tessellaria volvocina, Chrysodidymus synuroideus, six species of Synura and four species of Mallomonas. Sequences also were determined from multiple strains of some species, including 15 strains of Synura petersenii. The length of these sequences varied from 495–598 bp. The large amount of ITS/5.8S length variation made initial attempts in determining reliable sequence alignment difficult and precluded their use in phylogenetic analyses of the class. Subsequently, the approach of Bogler & Simpson (1996) was investigated where reiterative, computer assisted alignments were generated and the quality of the alignment was evaluated by homoplasy index and consistency index values. However, these alignments also were equivocal. ITS/5.8S sequences sorted the 15 S. petersenii strains into two well supported ITS lineages. One ITS type included ten isolates from North America while isolates from the second ITS type included one each from Germany and Australia and three from North America. Results are presented here where the sequences from the 15 S. petersenii isolates were used to characterize ITS-1 and ITS-2 RNA transcript secondary structure. Next, this information was expanded to include ITS/5.8S sequences from the other taxa in the class. Finally, the characteristics of ITS 1 and ITS 2 RNA transcript secondary structure were used as a guide to align all of the ITS/5.8S sequences from the Synurophyceae in a final phylogenetic analysis.
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A floristic and biogeographic survey of the Synurophyceae from Southeastern Australia
Nordic Journal of Botany, 2000Co-Authors: Alane E. Furlotte, John A. Ferguson, James L WeeAbstract:The Synurophyceae are freshwater, golden-brown flagellates characterized by a cell covering of overlapping siliceous scales. Species-level identification usually requires electron microscopy of the scales, and numerous studies have demonstrated that most species of Synurophyceae have a worldwide distribution. Although algal endemism is suggested as relatively common in Australia, floristic investigations of the Synurophyceae in Australia are few in number, and southeastern Australia, in particular, is poorly represented in these studies. This study examines the Synurophyceae in south central Victoria, northeastern New South Wales, and southern, coastal Queensland in Australia. The sampled habitats include mountainous and boggy areas, temperate and subtropical rainforests, as well as pools, small ponds, lakes and reservoirs. Biogeographic and taxonomic information is emphasized. Eighty-six phytoplankton collections were made during June and July of 1996. Of these, 43 collections contain Synurophyceae. 18 Mallomonas taxa, 7 Synura taxa, Chrysodidymus synumideus, Tessellaria volvocina, and 3 unknown scale types were observed. Five taxa are reported for the first time in Australia and one is reported for the first time since its initial description in western Australia.
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A REASSESSMENT OF ITS/5.8S DNA SEQUENCE VARIATION AND PHYLOGENETIC SIGNAL IN THE Synurophyceae
Journal of Phycology, 2000Co-Authors: James L WeeAbstract:Previously, DNA sequences were determined for the entire ITS/5.8S region by direct sequencing of PCR amplification products. 28 sequences were obtained from 12 species of Synurophyceae, including Tessellaria volvocina, Chrysodidymus synuroideus, six species of Synura and four species of Mallomonas. Sequences also were determined from multiple strains of some species, including 15 strains of Synura petersenii. The length of these sequences varied from 495–598 bp. The large amount of ITS/5.8S length variation made initial attempts in determining reliable sequence alignment difficult and precluded their use in phylogenetic analyses of the class. Subsequently, the approach of Bogler & Simpson (1996) was investigated where reiterative, computer assisted alignments were generated and the quality of the alignment was evaluated by homoplasy index and consistency index values. However, these alignments also were equivocal. ITS/5.8S sequences sorted the 15 S. petersenii strains into two well supported ITS lineages. One ITS type included ten isolates from North America while isolates from the second ITS type included one each from Germany and Australia and three from North America. Results are presented here where the sequences from the 15 S. petersenii isolates were used to characterize ITS-1 and ITS-2 RNA transcript secondary structure. Next, this information was expanded to include ITS/5.8S sequences from the other taxa in the class. Finally, the characteristics of ITS 1 and ITS 2 RNA transcript secondary structure were used as a guide to align all of the ITS/5.8S sequences from the Synurophyceae in a final phylogenetic analysis.
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production of the taste odor causing compound trans 2 cis 6 nonadienal within the Synurophyceae
Journal of Applied Phycology, 1994Co-Authors: James L Wee, Susan A Harris, James P Smith, Christopher P Dionigi, David F MillieAbstract:Although several species of the Synurophyceae have been associated with taste and odor problems in potable water supplies, electron microscopic-based field studies linked problematic blooms only toSynura petersenii Korshikov. Eventually, the organic compoundtrans-2,cis-6-nonadienal was implicated to cause the associated ‘cucumberlike’ odors. The objective of this study was to survey unialgal cultures of various Synurophycean species for the occurrence oftrans-2,cis-6-nonadienal. The compound was detected throughout a 24-day growth assay with aS. petersenii isolate, but was not detected in an identical assay withSynura sphagnicola (Korshikov) Korshikov. In separate 24-day cultures,trans-2,cis-6-nonadienal was detected in two isolates from theS. petersenii species complex, but was not detected in isolates of twoMallomonas or fourSynura taxa not from theS. petersenii complex. These results support the hypothesis that production oftrans-2,cis-6-nonadienal is unique to taxa within theS. petersenii complex. When contrast-enhancing optics and specific specimen preparation techniques are employed, light microscopy can be used to distinguish taxa in theS. petersenii complex from all other Synurophycean taxa. These methods are suggested as an efficient way to monitortrans-2,cis-6-nonadienal-producing taxa in potable water supplies.
David F Millie - One of the best experts on this subject based on the ideXlab platform.
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production of the taste odor causing compound trans 2 cis 6 nonadienal within the Synurophyceae
Journal of Applied Phycology, 1994Co-Authors: James L Wee, Susan A Harris, James P Smith, Christopher P Dionigi, David F MillieAbstract:Although several species of the Synurophyceae have been associated with taste and odor problems in potable water supplies, electron microscopic-based field studies linked problematic blooms only toSynura petersenii Korshikov. Eventually, the organic compoundtrans-2,cis-6-nonadienal was implicated to cause the associated ‘cucumberlike’ odors. The objective of this study was to survey unialgal cultures of various Synurophycean species for the occurrence oftrans-2,cis-6-nonadienal. The compound was detected throughout a 24-day growth assay with aS. petersenii isolate, but was not detected in an identical assay withSynura sphagnicola (Korshikov) Korshikov. In separate 24-day cultures,trans-2,cis-6-nonadienal was detected in two isolates from theS. petersenii species complex, but was not detected in isolates of twoMallomonas or fourSynura taxa not from theS. petersenii complex. These results support the hypothesis that production oftrans-2,cis-6-nonadienal is unique to taxa within theS. petersenii complex. When contrast-enhancing optics and specific specimen preparation techniques are employed, light microscopy can be used to distinguish taxa in theS. petersenii complex from all other Synurophycean taxa. These methods are suggested as an efficient way to monitortrans-2,cis-6-nonadienal-producing taxa in potable water supplies.
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Production of the taste/odor-causing compound,trans-2,cis-6-nonadienal, within the Synurophyceae
Journal of Applied Phycology, 1994Co-Authors: James L Wee, Susan A Harris, James P Smith, Christopher P Dionigi, David F MillieAbstract:Although several species of the Synurophyceae have been associated with taste and odor problems in potable water supplies, electron microscopic-based field studies linked problematic blooms only to Synura petersenii Korshikov. Eventually, the organic compound trans -2, cis -6-nonadienal was implicated to cause the associated ‘cucumberlike’ odors. The objective of this study was to survey unialgal cultures of various Synurophycean species for the occurrence of trans -2, cis -6-nonadienal. The compound was detected throughout a 24-day growth assay with a S. petersenii isolate, but was not detected in an identical assay with Synura sphagnicola (Korshikov) Korshikov. In separate 24-day cultures, trans -2, cis -6-nonadienal was detected in two isolates from the S. petersenii species complex, but was not detected in isolates of two Mallomonas or four Synura taxa not from the S. petersenii complex. These results support the hypothesis that production of trans -2, cis -6-nonadienal is unique to taxa within the S. petersenii complex. When contrast-enhancing optics and specific specimen preparation techniques are employed, light microscopy can be used to distinguish taxa in the S. petersenii complex from all other Synurophycean taxa. These methods are suggested as an efficient way to monitor trans -2, cis -6-nonadienal-producing taxa in potable water supplies.
Jorgen Kristiansen - One of the best experts on this subject based on the ideXlab platform.
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mallomonas parana Synurophyceae synurales a new chrysophyte species from a river flood plain lake of the parana river system argentina
Nordic Journal of Botany, 2003Co-Authors: Maria Susana Vigna, Jorgen KristiansenAbstract:Mallomonas parana sp. nov. (Synurophyceae, Synurales) was found in a river flood-plain lake of the Parana River system, Santa Fe Province, Argentina. Transmission and scanning electron microscopic observations were made. The new taxon is referred to the series Allorgei of the section Quadratae, and biogeographical aspects of this series are dicusssed.
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Mallomonas parana (Synurophyceae, Synurales), a new chrysophyte species from a river flood‐plain lake of the Parana River system, Argentina
Nordic Journal of Botany, 2003Co-Authors: Maria Susana Vigna, Jorgen KristiansenAbstract:Mallomonas parana sp. nov. (Synurophyceae, Synurales) was found in a river flood-plain lake of the Parana River system, Santa Fe Province, Argentina. Transmission and scanning electron microscopic observations were made. The new taxon is referred to the series Allorgei of the section Quadratae, and biogeographical aspects of this series are dicusssed.
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chrysophyceae y Synurophyceae de tierra del fuego argentina
Monografías del Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", 2002Co-Authors: Jorgen Kristiansen, Maria Susana VignaAbstract:Chrysophyceae and Synurophyceae of Tierra del Fuego, Argentina. This monograph deals with the study of the Chrysophyceae and Synurophyceae of Tierra del Fuego, Argentina. One hundred and one samples are studied. Twenty-one taxa of Chrysophyceae and thirty-four taxa of Synurophyceae are described, among them forty-two taxa are studied by means of transmission and scanning electron microscopy. Synura spinosa has the widest distribution in the studied area. Chrysopyxis inaequalis, C. iwanoffi, Lagynium delicatulum, L. janei, Chrysococcus rufescens, Ch. triporus, Epipyxis utriculus var. acuta, Spiniferomonas abei, Synura petersenii f. glabra and Mallomonas pillula f. valdiviana, are recorded for the first time for Argentina. The biogeographic distribution of the species is analized. Descriptions of all the taxa, keys to genera, sections and species, illustrations, and notes on the habitat for each species are presented.
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Silica-scaled chrysophytes in Bulgaria
Cryptogamie Algologie, 1998Co-Authors: Jorgen Kristiansen, Maya P. StoynevaAbstract:Treize especes de chrysophytes a ecailles silicieuses (Chrysophyceae et Synurophyceae) ont ete identifiees par examen, en microscopie electronique a transmission, d'echantillons de 21 localites d'eau douce (lacs, etangs, tourbieres et rivieres), en Bulgarie. Trois de ces especes etaient deja signalees en Bulgarie, mais une seule avait fait l'objet d'une etude en microscopie electronique. Huit des especes sont cosmopolites, les cinq autres sont limitees aux regions temperees, dont deux avec une distribution temperee bipolaire. Presque toutes ces especes sont connues dans des pays limitrophes.
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STUDIES ON SILICA-SCALED CHRYSOPHYTES FROM FUJIAN PROVINCE, CHINA
Chinese Journal of Oceanology and Limnology, 1998Co-Authors: Wei Yin-xin, Jorgen KristiansenAbstract:In 19 phytoplankton samples collected from 14 water bodies in the southeasterm part of China and examined by electron microscopy, 27 taxa of silica-scaled chrysophytes (8 of them belonging to the Chrysophyceae and 19 to the Synurophyceae) were found. All these taxa are new to Fujian Province; 24 of them were previously found in China, but 3, viz.Chrysosphaerella septispina, Mallomonas rasilis andM. guttata var.simplex are new to China.M. guttata var.simplex has only been reported from the Ontario region, Canada. The silica-scaled chrysophyte flora and their geographical distribution in this region are discussed.
James P Smith - One of the best experts on this subject based on the ideXlab platform.
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production of the taste odor causing compound trans 2 cis 6 nonadienal within the Synurophyceae
Journal of Applied Phycology, 1994Co-Authors: James L Wee, Susan A Harris, James P Smith, Christopher P Dionigi, David F MillieAbstract:Although several species of the Synurophyceae have been associated with taste and odor problems in potable water supplies, electron microscopic-based field studies linked problematic blooms only toSynura petersenii Korshikov. Eventually, the organic compoundtrans-2,cis-6-nonadienal was implicated to cause the associated ‘cucumberlike’ odors. The objective of this study was to survey unialgal cultures of various Synurophycean species for the occurrence oftrans-2,cis-6-nonadienal. The compound was detected throughout a 24-day growth assay with aS. petersenii isolate, but was not detected in an identical assay withSynura sphagnicola (Korshikov) Korshikov. In separate 24-day cultures,trans-2,cis-6-nonadienal was detected in two isolates from theS. petersenii species complex, but was not detected in isolates of twoMallomonas or fourSynura taxa not from theS. petersenii complex. These results support the hypothesis that production oftrans-2,cis-6-nonadienal is unique to taxa within theS. petersenii complex. When contrast-enhancing optics and specific specimen preparation techniques are employed, light microscopy can be used to distinguish taxa in theS. petersenii complex from all other Synurophycean taxa. These methods are suggested as an efficient way to monitortrans-2,cis-6-nonadienal-producing taxa in potable water supplies.
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Production of the taste/odor-causing compound,trans-2,cis-6-nonadienal, within the Synurophyceae
Journal of Applied Phycology, 1994Co-Authors: James L Wee, Susan A Harris, James P Smith, Christopher P Dionigi, David F MillieAbstract:Although several species of the Synurophyceae have been associated with taste and odor problems in potable water supplies, electron microscopic-based field studies linked problematic blooms only to Synura petersenii Korshikov. Eventually, the organic compound trans -2, cis -6-nonadienal was implicated to cause the associated ‘cucumberlike’ odors. The objective of this study was to survey unialgal cultures of various Synurophycean species for the occurrence of trans -2, cis -6-nonadienal. The compound was detected throughout a 24-day growth assay with a S. petersenii isolate, but was not detected in an identical assay with Synura sphagnicola (Korshikov) Korshikov. In separate 24-day cultures, trans -2, cis -6-nonadienal was detected in two isolates from the S. petersenii species complex, but was not detected in isolates of two Mallomonas or four Synura taxa not from the S. petersenii complex. These results support the hypothesis that production of trans -2, cis -6-nonadienal is unique to taxa within the S. petersenii complex. When contrast-enhancing optics and specific specimen preparation techniques are employed, light microscopy can be used to distinguish taxa in the S. petersenii complex from all other Synurophycean taxa. These methods are suggested as an efficient way to monitor trans -2, cis -6-nonadienal-producing taxa in potable water supplies.
Susan A Harris - One of the best experts on this subject based on the ideXlab platform.
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production of the taste odor causing compound trans 2 cis 6 nonadienal within the Synurophyceae
Journal of Applied Phycology, 1994Co-Authors: James L Wee, Susan A Harris, James P Smith, Christopher P Dionigi, David F MillieAbstract:Although several species of the Synurophyceae have been associated with taste and odor problems in potable water supplies, electron microscopic-based field studies linked problematic blooms only toSynura petersenii Korshikov. Eventually, the organic compoundtrans-2,cis-6-nonadienal was implicated to cause the associated ‘cucumberlike’ odors. The objective of this study was to survey unialgal cultures of various Synurophycean species for the occurrence oftrans-2,cis-6-nonadienal. The compound was detected throughout a 24-day growth assay with aS. petersenii isolate, but was not detected in an identical assay withSynura sphagnicola (Korshikov) Korshikov. In separate 24-day cultures,trans-2,cis-6-nonadienal was detected in two isolates from theS. petersenii species complex, but was not detected in isolates of twoMallomonas or fourSynura taxa not from theS. petersenii complex. These results support the hypothesis that production oftrans-2,cis-6-nonadienal is unique to taxa within theS. petersenii complex. When contrast-enhancing optics and specific specimen preparation techniques are employed, light microscopy can be used to distinguish taxa in theS. petersenii complex from all other Synurophycean taxa. These methods are suggested as an efficient way to monitortrans-2,cis-6-nonadienal-producing taxa in potable water supplies.
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Production of the taste/odor-causing compound,trans-2,cis-6-nonadienal, within the Synurophyceae
Journal of Applied Phycology, 1994Co-Authors: James L Wee, Susan A Harris, James P Smith, Christopher P Dionigi, David F MillieAbstract:Although several species of the Synurophyceae have been associated with taste and odor problems in potable water supplies, electron microscopic-based field studies linked problematic blooms only to Synura petersenii Korshikov. Eventually, the organic compound trans -2, cis -6-nonadienal was implicated to cause the associated ‘cucumberlike’ odors. The objective of this study was to survey unialgal cultures of various Synurophycean species for the occurrence of trans -2, cis -6-nonadienal. The compound was detected throughout a 24-day growth assay with a S. petersenii isolate, but was not detected in an identical assay with Synura sphagnicola (Korshikov) Korshikov. In separate 24-day cultures, trans -2, cis -6-nonadienal was detected in two isolates from the S. petersenii species complex, but was not detected in isolates of two Mallomonas or four Synura taxa not from the S. petersenii complex. These results support the hypothesis that production of trans -2, cis -6-nonadienal is unique to taxa within the S. petersenii complex. When contrast-enhancing optics and specific specimen preparation techniques are employed, light microscopy can be used to distinguish taxa in the S. petersenii complex from all other Synurophycean taxa. These methods are suggested as an efficient way to monitor trans -2, cis -6-nonadienal-producing taxa in potable water supplies.
