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Charles Yarish - One of the best experts on this subject based on the ideXlab platform.
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bioremediation efficiency in the removal of dissolved inorganic nutrients by the red seaweed Porphyra yezoensis cultivated in the open sea
Water Research, 2008Co-Authors: Hanye Zhang, Shanshan Wen, Yongjing Dai, Senjie Lin, Charles YarishAbstract:Abstract The bioremediation capability and efficiency of large-scale Porphyra cultivation in the removal of inorganic nitrogen and phosphorus from open sea area were studied. The study took place in 2002–2004, in a 300 ha nori farm along the Lusi coast, Qidong County, Jiangsu Province, China, where the valuable rhodophyte seaweed Porphyra yezoensis has been extensively cultivated. Nutrient concentrations were significantly reduced by the seaweed cultivation. During the non-cultivation period of P. yezoensis , the concentrations of NH 4 -N, NO 2 -N, NO 3 -N and PO 4 -P were 43–61, 1–3, 33–44 and 1–3 μmol L −1 , respectively. Within the Porphyra cultivation area, the average nutrient concentrations during the Porphyra cultivation season were 20.5, 1.1, 27.9 and 0.96 μmol L −1 for NH 4 -N, NO 2 -N, NO 3 -N and PO 4 -P, respectively, significantly lower than in the non-cultivation season ( p Porphyra farming resulted in the reduction of NH 4 -N, NO 2 -N, NO 3 -N and PO 4 -P by 50–94%, 42–91%, 21–38% and 42–67%, respectively. Nitrogen and phosphorus contents in dry Porphyra thalli harvested from the Lusi coast averaged 6.3% and 1.0%, respectively. There were significant monthly variations in tissue nitrogen content ( p p >0.05). The highest tissue nitrogen content, 7.65% in dry wt, was found in December and the lowest value, 4.85%, in dry wt, in April. The annual biomass production of P. yezoensis was about 800 kg dry wt ha −1 at the Lusi Coast in 2003–2004. An average of 14708.5 kg of tissue nitrogen and 2373.5 kg of tissue phosphorus in P. yezoensis biomass were harvested annually from 300 ha of cultivation from Lusi coastal water. These results indicated that Porphyra efficiently removed excess nutrient from nearshore eutrophic coastal areas. Therefore, large-scale cultivation of P. yezoensis could alleviate eutrophication in coastal waters economically.
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exploring northeast american and asian species of Porphyra for use in an integrated finfish algal aquaculture system
Aquaculture, 2006Co-Authors: George P Kraemer, R Carmona, Charles YarishAbstract:Many aquaculture industries generate a nutrient-rich waste stream that can lead to eutrophication of coastal waters. To address this environmental issue, the bioremediation potential of several native Northeast American species of Porphyra was assessed and compared to the well-known Asian species. Porphyra thalli were cultured over 4 weeks at 15 °C at a stocking density of 0.4 g FW L �1 . At 3- to 4-day intervals nutrient uptake, tissue N accumulation and phycobiliprotein concentration (PBP) were determined as functions of nitrogen (N) concentration (25–300 μM) and N source (nitrate vs. ammonium). Growth rates were measured weekly. Growth and tissue N reached maximal levels at inorganic N concentrations of 150–300 μM. Maximum growth rates ranged from 10% to 25% day �1 , although induction of archeospores reduced average growth rates in many cases. No evidence of ammonium toxicity (reductions in growth rate) was observed; in fact, similar values were found with both N sources. Ammonium generally yielded higher PBP and tissue N contents than nitrate. Porphyra amplissima presented the highest growth rate, followed by the Asian Porphyra yezoensis. Under the experimental conditions, Porphyra spp. removed 70–100% of N within 3–4 days at N concentrations up to 150 μM, but was less efficient in removing inorganic phosphorus (35–91% removal). The highest tissue N and PBP concentrations were found at 150–300 μM of N, with N values close to 7% DW. Overall, Porphyra appears to be an excellent choice for bioremediation of moderately eutrophic effluents, with the added benefit that tissue may be harvested for sale.
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Identification of north-western Atlantic Porphyra (Bangiaceae, Bangiales) based on sequence variation in nuclear SSU and plastid rbcL genes
Phycologia, 2003Co-Authors: Anita S. Klein, Christopher D. Neefus, Danielle F. Cain, Heather A. Taylor, Andrew L. West, Juliet Brodie, Brian W. Teasdale, Edward J Hehre, Arthur C. Mathieson, Charles YarishAbstract:Six species of Porphyra have commonly been recognized in the north-western Atlantic from Long Island Sound to the Canadian Maritimes: P. amplissima, P. leucosticta, P. linearis, P. miniata, P. purpurea, and P. umbilicalis. Distinguishing them with certainty has been problematic. A DNA-based system of molecular identification was developed using partial sequences of the nuclear small subunit ribosomal RNA gene (SSU) or the plastid ribulose-1.5-bisphosphate carboxylase-oxygenase large subunit gene (rbcL). Multiple samples of each taxon were surveyed for intraspecific variation. Intraspecific SSU divergences for Porphyra 'lelucosticta', P. 'miniata', P 'umbilicalis', and P. 'purpurea' ranged from 0% to 1%. There was more variation for P. 'amplissima' (0-2.1%) and P. 'linearis' (0-3.5%); however, each taxon was monophyletic. No intraspecific differences were observed for these taxa in rbcL (one to eight samples per taxon). These sequences were compared with P. yezoensis U51, introduced to Maine, and with P. 'dioica', a north-east Atlantic Porphyra easily confused with P. 'purpurea'. To discriminate between P. 'purpurea'. P. 'umbilicalis', and P. 'leucosticta', SSU variation was used to design primers for the Allele-Specific Polymerase Chain Reaction. With molecular tools we could classify over 80% of the monostromatic specimens surveyed, but the residue of unidentifiable specimens may indicate the existence of further monostromatic species in the north-west Atlantic. Porphyra 'purpurea' was found to occur further south than previously recorded. A morphologically cryptic Porphyra was discovered at Herring Cove, Nova Scotia. Canada. Phylogenetic analyses using SSU or rbcL sequences showed 'soft incongruence' between gene trees, i.e. the topologies of the phylograms were similar but not identical, with only weak to moderate bootstrap support for the nodes that differed. Both trees strongly supported a elide including P. 'purpurea', P. 'umbilicalis', P. 'linearis', and P. 'dioica'. Porphyra sp. Herring Cove was allied with the remaining Porphyra taxa in the SSU tree. The rbcL phylogeny was less well resolved, consisting of a polytomy of a P. 'purpurea'-P. 'umbilicalis'-P. 'linearis'-P. "dioica' clade. Porphyra sp. Herring Cove, a clade comprising P. 'amplissima' and P. 'miniata', and a P. 'suborbiculata'-P. 'leucosticta'-P. yezoensis clade.
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A reassessment of the taxonomic status of Porphyra suborbiculata, Porphyra carolinensis and Porphyra lilliputiana (Bangiales, Rhodophyta) based on molecular and morphological data
European Journal of Phycology, 2002Co-Authors: Judy E. Broom, Charles Yarish, Wendy A. Nelson, Wyn A. Jones, R. Aguilar Rosas, L.e Aguilar RosasAbstract:We examined three species of diminutive Porphyra, Porphyra suborbiculata Kjellman from the North Pacific, Porphyra lilliputiana W. A. Nelson, G. A. Knight et M. W. Hawkes from the South Pacific, and Porphyra carolinensis Coll et J. Cox from the western North Atlantic. These taxa were compared in terms of morphology, habitat data and sequence haplotypes of nuclear small subunit rDNA (SSU) and internal transcribed spacers of the nuclear rDNA cistron (ITS). These three species have similar morphologies and growth habits, and share very similar type descriptions and habitat records. Haplotype variation was found within the 11 samples of P. lilliputiana we examined and within P. suborbiculata samples from two locations, but the single P. carolinensis haplotype (from collections from two separate locations) was identical to one found in several widespread P. lilliputiana samples. Unrooted phylogenetic trees based on sequence data do not support any of the three species as being a monophyletic group. We conclude...
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Porphyra SUBORBICULATA, Porphyra CAROLINENSIS AND Porphyra LILLIPUTIANA ‐ THREE NAMES FOR ONE SMALL Porphyra
Journal of Phycology, 2000Co-Authors: J. E. Broom, Charles Yarish, Wendy A. Nelson, Wyn A. Jones, R. Aguilar Rosas, L.e Aguilar RosasAbstract:The genus Porphyra is ancient, successful, and morphologically simple. Its members provide a particular challenge to systematists who must decide whether shared features are a result of homoplasy, or reflect recent common ancestry. Three species of diminutive Porphyra with widespread geographic origins share many common morphological features: P suborbiculata Kjellm. has been reported from the west Pacific and Indian Oceans, P. carolinensis Coll et J. Cox from the west Atlantic, and P lilliputiana W. A. Nelson, G. A.Knight et M. W. Hawkes from New Zealand. Comparison of 18S rDNA sequence data from small Porphyra thalli from Mexico, Japan, New Zealand, Australia and Connecticut indicate that these three taxa in fact belong to one cosmopolitan species, which is distributed over three oceans and two hemispheres. Analysis of sequence data from introns present in the 18S rDNA and from the ITS region suggest that this distribution may be linked to human activity, and raises the question of to which geographic locality this entity is truly endemic?
Quanbin Zhang - One of the best experts on this subject based on the ideXlab platform.
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in vitro evaluation of the neuroprotective effect of oligo Porphyran from Porphyra yezoensis in pc12 cells
Journal of Applied Phycology, 2019Co-Authors: Yingjuan Liu, Jing Wang, Zhenzhen Deng, Lihua Geng, Quanbin ZhangAbstract:Porphyran, derived from the marine red algae Porphyra and Pyropia, is a type of polysaccharide. Oligo-Porphyran (OP) was prepared from Porphyran (isolated from Pyropia yezoensis) through the acidolysis reaction containing a linear backbone of alternating 3-linked β-d-galactose and 4-linked α-l-galactose-6-sulfate. Our previous studies have shown that oligo-Porphyran could attenuate MPTP-induced behavioral deficits in mice by inhibiting the tyrosine hydroxylase (TH) loss. In the present study, we further investigated how OP protects the dopamine neurons from loss in PC12 cells. OP significantly attenuated LDH release and the production of reactive oxygen species (ROS) lesioned by 6-OHDA. Moreover, OP alleviated the mitochondrial membrane potential (MMP) loss, the ratio of Bax/Bcl-2, and upregulated the PI3K/ Akt/PKC pathway, the level of tyrosine hydroxylase (TH), and dopamine transporter (DAT). Furthermore, OP decreased the production of proinflammatory cytokines. Terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) staining further indicated that OP treatment inhibited apoptosis. These results might contribute to the overall understanding of the potential health benefits of OP for food and drug applications.
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regioselective syntheses of sulfated Porphyrans from Porphyra haitanensis and their antioxidant and anticoagulant activities in vitro
Carbohydrate Polymers, 2010Co-Authors: Zhongshan Zhang, Quanbin Zhang, Jing Wang, Houfang Song, Hong Zhang, Xizhen NiuAbstract:Porphyran extracted from Porphyra haitanensis is a sulfated polysaccharide, which possesses excellent antioxidant activities. In this study, we prepared Porphyran and alkali-treated Porphyran and their derivatives, sulfated Porphyran. And then we evaluated their antioxidant and anticoagulant activities in vitro and characterized the relationship between activities and chemical characteristics. The activities were strongly dependant on the degree of sulfation and the position of sulfate. In this study, the antioxidant activities mainly depend on degree of substitution, and the anticoagulant activities mainly depend on the position of sulfate. Further studies are needed to improve our understanding of antioxidant and anticoagulant activities mechanism. (c) 2009 Elsevier Ltd. All rights reserved.
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chemical modification and influence of function groups on the in vitro antioxidant activities of Porphyran from Porphyra haitanensis
Carbohydrate Polymers, 2010Co-Authors: Zhongshan Zhang, Quanbin Zhang, Jing Wang, Houfang Song, Hong Zhang, Xizhen NiuAbstract:Porphyran extracted from Porphyra haitanensis is a sulfated polysaccharide, which possesses excellent antioxidant activities. In this study, we prepared Porphyran and alkali-treated Porphyran and their derivatives, sulfated Porphyran and acetylated Porphyran. Their antioxidant activities including scavenging effect on superoxide radical, 1,1-diphenyl-2-picrylhydrazyl radical and reducing power were investigated. The results of chemical analysis and FT-IR spectrums indicated that the modification was successful. And in addition, we found that certain derivative exhibited stronger antioxidant activity than raw material Porphyran. The sulfated derivative with certain DS showed stronger antioxidant activity. The acetylated derivative showed the most excellent antioxidant activity in three assays we made, and so this derivative needs to be attended to. (C) 2009 Elsevier Ltd. All rights reserved.
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in vitro antioxidant activities of acetylated phosphorylated and benzoylated derivatives of Porphyran extracted from Porphyra haitanensis
Carbohydrate Polymers, 2009Co-Authors: Zhongshan Zhang, Quanbin Zhang, Jing Wang, Houfang Song, Xuelian Shi, Jingjing ZhangAbstract:Porphyran extracted from red algae Porphyra haitanensis is a sulfated polysaccharide, which possesses excellent antioxidant activities. In this study, we prepared the acetylated, phosphorylated and benzoylated derivatives of Porphyran. And then the antioxidant activities of all the samples were investigated including scavenging effects of superoxide and hydroxyl radicals and reducing power. The results of chemical analysis and FT-IR spectrum showed the modifications of Porphyran were successful. And in addition, we found that certain derivative exhibited stronger antioxidant activity than raw material. And the mechanism of the structure-function relationship of these derivatives needs to be attended to. (C) 2009 Elsevier Ltd. All rights reserved.
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preparation of the different derivatives of the low molecular weight Porphyran from Porphyra haitanensis and their antioxidant activities in vitro
International Journal of Biological Macromolecules, 2009Co-Authors: Zhongshan Zhang, Quanbin Zhang, Jing Wang, Hong Zhang, Xizhen NiuAbstract:Porphyran extracted from Porphyra haitanensis is a sulfated polysaccharide, which possesses excellent antioxidant activities. In this study, we prepared one low-molecular-weight Porphyran and its sulfated, acetylated, phosphorylated and benzoylated derivatives. Their antioxidant activities were investigated including scavenging effect of superoxide, hydroxyl and 1,1-diphenyl-2-picrylhydrazyl radicals. The results of chemical analysis and FT-IR spectrums showed the modification was successful. And in addition, we found that certain derivative exhibited stronger antioxidant activity than low-molecular-weight Porphyran. The benzoylated derivative showed the most excellent antioxidant activity in three assays, so this derivative needs to be attended to.
Wendy A. Nelson - One of the best experts on this subject based on the ideXlab platform.
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Porphyra migitae sp. nov. (Bangiales, Rhodophyta) from Japan
Phycologia, 2010Co-Authors: Norio Kikuchi, Wendy A. Nelson, Shogo Arai, Goro Yoshida, Jong-ahm Shin, Judy E. Broom, Masahiko MiyataAbstract:Abstract Kikuchi N., Arai S., Yoshida G., Shin J.-A., Broom J.E., Nelson W.A. and Miyata M. 2010. Porphyra migitae sp. nov. (Bangiales, Rhodophyta) from Japan. Phycologia 49: 345–354. DOI: 10.2216/09-82.1 A new species of Porphyra, Porphyra migitae sp. nov., coloured fire red and collected subtidally in two localities in Japan, is described based on morphology, life history and molecular analyses. The new species can be distinguished from other fire-red coloured Porphyra species by a range of characters including the presence of conchospores and many archeospores and neutral spores on foliose thalli. Foliose thalli, which are sometimes lobed, are monoecious, and clearly distinguishable patches of spermatangial sori are not formed. Many holes are formed on the foliose thalli after release of spermatia. This species has a heteromorphic life history in which the macroscopic gametophytic foliose thalli alternate with the microscopic sporophytic filamentous thalli (conchocelis). In addition, the life history i...
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A reassessment of the taxonomic status of Porphyra suborbiculata, Porphyra carolinensis and Porphyra lilliputiana (Bangiales, Rhodophyta) based on molecular and morphological data
European Journal of Phycology, 2002Co-Authors: Judy E. Broom, Charles Yarish, Wendy A. Nelson, Wyn A. Jones, R. Aguilar Rosas, L.e Aguilar RosasAbstract:We examined three species of diminutive Porphyra, Porphyra suborbiculata Kjellman from the North Pacific, Porphyra lilliputiana W. A. Nelson, G. A. Knight et M. W. Hawkes from the South Pacific, and Porphyra carolinensis Coll et J. Cox from the western North Atlantic. These taxa were compared in terms of morphology, habitat data and sequence haplotypes of nuclear small subunit rDNA (SSU) and internal transcribed spacers of the nuclear rDNA cistron (ITS). These three species have similar morphologies and growth habits, and share very similar type descriptions and habitat records. Haplotype variation was found within the 11 samples of P. lilliputiana we examined and within P. suborbiculata samples from two locations, but the single P. carolinensis haplotype (from collections from two separate locations) was identical to one found in several widespread P. lilliputiana samples. Unrooted phylogenetic trees based on sequence data do not support any of the three species as being a monophyletic group. We conclude...
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Porphyra SUBORBICULATA, Porphyra CAROLINENSIS AND Porphyra LILLIPUTIANA ‐ THREE NAMES FOR ONE SMALL Porphyra
Journal of Phycology, 2000Co-Authors: J. E. Broom, Charles Yarish, Wendy A. Nelson, Wyn A. Jones, R. Aguilar Rosas, L.e Aguilar RosasAbstract:The genus Porphyra is ancient, successful, and morphologically simple. Its members provide a particular challenge to systematists who must decide whether shared features are a result of homoplasy, or reflect recent common ancestry. Three species of diminutive Porphyra with widespread geographic origins share many common morphological features: P suborbiculata Kjellm. has been reported from the west Pacific and Indian Oceans, P. carolinensis Coll et J. Cox from the west Atlantic, and P lilliputiana W. A. Nelson, G. A.Knight et M. W. Hawkes from New Zealand. Comparison of 18S rDNA sequence data from small Porphyra thalli from Mexico, Japan, New Zealand, Australia and Connecticut indicate that these three taxa in fact belong to one cosmopolitan species, which is distributed over three oceans and two hemispheres. Analysis of sequence data from introns present in the 18S rDNA and from the ITS region suggest that this distribution may be linked to human activity, and raises the question of to which geographic locality this entity is truly endemic?
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Epiphytic species of Porphyra (Bangiales, Rhodophyta) from New Zealand
Botanica Marina, 1993Co-Authors: Wendy A. NelsonAbstract:Two new epiphytic species of Porphyra (Bangiales, Rhodophyta) from New Zealand are described: Porphyra adamsiae sp. nov., a species found in the subantarctic growing on Cenacrum subsutum Ricker et Kraft, and Porphyra cameronii sp. nov., restricted to the brown alga Lessonia tholiformis Hay which is endemic to the Chatham Islands. Three epiphytic species of Porphyra (Bangiales, Rhodophyta) have been described previously from New Zealand waters: P. kaspar W. A. Nelson et N. M. Adams on Sargassum johnsonii Chapman, P. subtumens J. Agardh ex Laing on Durvillaea spp., P. woolhousiae Harvey on Macrocystis pyrifera L.) C. Agardh. Porphyra subtumens is lectotypified. All species of epiphytic Porphyra in New Zealand waters are monostromatic and monoecious
Bin Wang - One of the best experts on this subject based on the ideXlab platform.
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Genetic variation in 14 Porphyra lines using restriction site amplified polymorphism (RSAP)
Journal of Applied Phycology, 2011Co-Authors: Lixian Qiao, Baotai Guo, Jingshan Wang, Bin WangAbstract:Restriction site amplified polymorphism (RSAP) is a molecular marker technique which just requires a simple polymerase chain reaction to amplify fragments around restriction sites. The RSAP analytic system was set up and applied to Porphyra genetic variation analysis in this study for the first time. Fourteen Porphyra lines were screened by the RSAP analytic system with 30 primer combinations, 12 of which produced stable and reproducible amplification patterns in three repeated experiments. The 12 primer combinations produced 408 amplified fragments, 402 of which (98.53%) were polymorphic, with an average of 33.5 polymorphic fragments for each primer combination, ranging in size from 50 to 500 bp. The 408 fragments were scored one by one and then used to develop a dendrogram of the 14 Porphyra lines with unweighted pair-group method arithmetic average. The genetic distance among these Porphyra lines ranged from 0.10 to 0.50. These Porphyra lines were divided into two major groups at the 0.71 similarity level: one group contained only Porphyra haitanensis lines and the other group contained Porphyra yezoensis lines. In addition, some specific RSAP markers were acquired from each Porphyra line apart from P. yezoensis Yqd-2-1, and five of them were sequenced. One of the specific markers, R1/R3-8119 from P. yezoensis Y-9101, was successfully converted into sequence characterized amplification region marker. The result suggested that TRAP was a simple, stable, polymorphic, and reproducible molecular marker technique for the classification and resource protection of Porphyra lines.
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molecular identification of 16 Porphyra lines using sequence related amplified polymorphism markers
Aquatic Botany, 2007Co-Authors: Manli Weng, Delin Duan, Lixian Qiao, Baotai Guo, Hong-yu Liu, Ji-xun Dai, Bin WangAbstract:Sequence-related amplified polymorphism (SRAP) is a novel molecular marker technique designed to amplify open reading frames (ORFs). The SRAP analytic system was set up and applied to Porphyra germplasm identification in this study for the first time. Sixteen Porphyra lines were screened by SRAP technique with 30 primer combinations. In the analysis, 14 primer combinations produced stable and reproducible amplification patterns in three repetitive experiments. Among the total 533 amplified fragments, 522 (98%) were polymorphic, with an average of 38 fragments for each primer combination, ranging in size from 50 to 500 bp. The 533 fragments were visually scored one by one and then used to develop a dendrogram with Unweighted Pair-Group Method Arithmetic Average (UPGMA), and the 16 Porphyra lines were divided into two major groups at the 0.68 similarity level. From the total 533 fragments, 11 amplified by two primer combinations, ME1/EM1 and ME4/EM6, were used to develop the DNA fingerprints of the 16 Porphyra lines. The DNA fingerprints were then converted into binary codes, with 1 and 0 representing presence and absence of the corresponding amplified fragment, respectively. In the DNA fingerprints, each of the 16 Porphyra lines has its unique binary code and can be easily distinguished from the others. This is the first report on the development of SRAP technique and its utilization in germplasm identification of seaweeds. The results demonstrated that SRAP is a simple, stable, polymorphic and reproducible molecular marker technique for the classification and identification of Porphyra lines.
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Application of Target Region Amplification Polymorphism (TRAP) Technique to Porphyra (Bangiales, Rhodophyta) Fingerprinting
Phycologia, 2007Co-Authors: Lixian Qiao, Jianwei Sun, Tao Liu, Guo Baotai, Manli Weng, Hong-yu Liu, Feng Zhao, Ji-xun Dai, Bin WangAbstract:Abstract To demonstrate the applicability of the target region amplification polymorphism (TRAP) marker technique to Porphyra, 15 Porphyra lines, representing three species, were fingerprinted with 32 primer-combinations. Ten primer-combinations that gave a stable and reproducible amplification pattern were selected. In total 432 fragments from 50 to 500 base pairs (bp) in length were amplified with these 10 selected primer-combinations, and all the fragments were polymorphic. The 432 fragments were scored respectively and used to construct a dendrogram of the 15 Porphyra lines with unweighted pair-group method arithmetic average (UPGMA). These Porphyra lines were divided into two major groups at the 0.71 similarity level. This result is basically consistent with the conventional Porphyra taxonomy. Twelve of the 432 fragments, which were amplified by two primer-combinations, Tps/1F and Tps/3F, were chosen and used to develop the DNA fingerprints of these Porphyra lines. The developed DNA fingerprints then...
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Development of SSR primers from EST sequences and their application in germplasm identification of Porphyra lines (Rhodophyta)
European Journal of Phycology, 2006Co-Authors: Jianwei Sun, Tao Liu, Guo Baotai, Demin Jin, Manli Weng, Yanbin Feng, Delin Duan, Bin WangAbstract:This paper reports the development of SSR markers from EST data and their utilization in germplasm identification of Porphyra. The publicly available EST (expressed sequence tag) sequences of Porphyra were searched from the Internet (www.kazura.or.jp/en/plant/Porphyra/EST/). From a total of 20,779 obtained EST sequences, 391 SSRs (simple sequence repeats) were analysed with SSRIT software (www.gramene.org/db/searches/ssrtool). From those, 48 SSR primer-pairs were designed and tested by commonly used SSR reaction conditions using 22 Porphyra DNA samples as templates. Results showed that 41 SSR primer-pairs gave good amplification patterns. These were used to conduct SSR analyses of genetic diversity and variety identification of the 22 Porphyra lines. A dendrogram and the DNA fingerprints of the Porphyra lines were developed based on the obtained SSR data.
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Identification of Porphyra lines (rhodophyta) by AFLP DNA fingerprinting and molecular markers
Plant Molecular Biology Reporter, 2005Co-Authors: Jianwei Sun, Manli Weng, Min De Jin, Chunjiang Zhou, Qing Kai Yang, Lin De Duan, Bin WangAbstract:Twenty-seven Porphyra lines, including lines widely used in China, wild lines and lines introduced to China from abroad in recent years, were screened by random amplified polymorphic DNA (RAPD) technique with 120 operon primers. From the generated RAPD products, 11 bands that showed stable and repeatable RAPD patterns amplified by OPC-04, OPJ-18 and OPX-06, respectively were scored and used to develop the DNA fingerprints of the 27 Porphyra lines. Moreover, the DNA fingerprinting patterns were converted into computer language expressed with two digitals, 1 and 0, which represented the presence (numbered as 1) or absence (numbered as 0) of the corresponding band, respectively. Based on the above results, computerized DNA fingerprints were constructed in which each of the 27 Porphyra lines has its unique fingerprinting pattern and can be easily distinguished from others. Software named PGI (Porphyra germplasm identification) was designed for identification of the 27 Porphyra lines. In addition, seven specific RAPD markers from seven Porphyra lines were identified and two of them were successfully converted into SCAR (sequence characterized amplification region) markers. The developed DNA fingerprinting and specific molecular markers provide useful ways for the identification, classification and resource protection of the Porphyra lines.
L.e Aguilar Rosas - One of the best experts on this subject based on the ideXlab platform.
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A reassessment of the taxonomic status of Porphyra suborbiculata, Porphyra carolinensis and Porphyra lilliputiana (Bangiales, Rhodophyta) based on molecular and morphological data
European Journal of Phycology, 2002Co-Authors: Judy E. Broom, Charles Yarish, Wendy A. Nelson, Wyn A. Jones, R. Aguilar Rosas, L.e Aguilar RosasAbstract:We examined three species of diminutive Porphyra, Porphyra suborbiculata Kjellman from the North Pacific, Porphyra lilliputiana W. A. Nelson, G. A. Knight et M. W. Hawkes from the South Pacific, and Porphyra carolinensis Coll et J. Cox from the western North Atlantic. These taxa were compared in terms of morphology, habitat data and sequence haplotypes of nuclear small subunit rDNA (SSU) and internal transcribed spacers of the nuclear rDNA cistron (ITS). These three species have similar morphologies and growth habits, and share very similar type descriptions and habitat records. Haplotype variation was found within the 11 samples of P. lilliputiana we examined and within P. suborbiculata samples from two locations, but the single P. carolinensis haplotype (from collections from two separate locations) was identical to one found in several widespread P. lilliputiana samples. Unrooted phylogenetic trees based on sequence data do not support any of the three species as being a monophyletic group. We conclude...
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Porphyra SUBORBICULATA, Porphyra CAROLINENSIS AND Porphyra LILLIPUTIANA ‐ THREE NAMES FOR ONE SMALL Porphyra
Journal of Phycology, 2000Co-Authors: J. E. Broom, Charles Yarish, Wendy A. Nelson, Wyn A. Jones, R. Aguilar Rosas, L.e Aguilar RosasAbstract:The genus Porphyra is ancient, successful, and morphologically simple. Its members provide a particular challenge to systematists who must decide whether shared features are a result of homoplasy, or reflect recent common ancestry. Three species of diminutive Porphyra with widespread geographic origins share many common morphological features: P suborbiculata Kjellm. has been reported from the west Pacific and Indian Oceans, P. carolinensis Coll et J. Cox from the west Atlantic, and P lilliputiana W. A. Nelson, G. A.Knight et M. W. Hawkes from New Zealand. Comparison of 18S rDNA sequence data from small Porphyra thalli from Mexico, Japan, New Zealand, Australia and Connecticut indicate that these three taxa in fact belong to one cosmopolitan species, which is distributed over three oceans and two hemispheres. Analysis of sequence data from introns present in the 18S rDNA and from the ITS region suggest that this distribution may be linked to human activity, and raises the question of to which geographic locality this entity is truly endemic?
