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Shoshana Arad - One of the best experts on this subject based on the ideXlab platform.
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genes involved in the endoplasmic reticulum n glycosylation pathway of the red microalga Porphyridium sp a bioinformatic study
International Journal of Molecular Sciences, 2014Co-Authors: Oshrat Levyontman, Merav Fisher, Yoram Shotland, Yacob Weinstein, Yoram Tekoah, Shoshana AradAbstract:N-glycosylation is one of the most important post-translational modifications that influence protein polymorphism, including protein structures and their functions. Although this important biological process has been extensively studied in mammals, only limited knowledge exists regarding glycosylation in algae. The current research is focused on the red microalga Porphyridium sp., which is a potentially valuable source for various applications, such as skin therapy, food, and pharmaceuticals. The enzymes involved in the biosynthesis and processing of N-glycans remain undefined in this species, and the mechanism(s) of their genetic regulation is completely unknown. In this study, we describe our pioneering attempt to understand the endoplasmic reticulum N-Glycosylation pathway in Porphyridium sp., using a bioinformatic approach. Homology searches, based on sequence similarities with genes encoding proteins involved in the ER N-glycosylation pathway (including their conserved parts) were conducted using the TBLASTN function on the algae DNA scaffold contigs database. This approach led to the identification of 24 encoded-genes implicated with the ER N-glycosylation pathway in Porphyridium sp. Homologs were found for almost all known N-glycosylation protein sequences in the ER pathway of Porphyridium sp.; thus, suggesting that the ER-pathway is conserved; as it is in other organisms (animals, plants, yeasts, etc.).
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unique n glycan moieties of the 66 kda cell wall glycoprotein from the red microalga Porphyridium sp
Journal of Biological Chemistry, 2011Co-Authors: Oshrat Levyontman, Shoshana Arad, David Harvey, Thomas B Parsons, Antony J Fairbanks, Yoram TekoahAbstract:We report here the structural determination of the N-linked glycans in the 66-kDa glycoprotein, part of the unique sulfated complex cell wall polysaccharide of the red microalga Porphyridium sp. Structures were elucidated by a combination of normal phase/reverse phase HPLC, positive ion MALDI-TOF MS, negative ion electrospray ionization, and MS/MS. The sugar moieties of the glycoprotein consisted of at least four fractions of N-linked glycans, each composed of the same four monosaccharides, GlcNAc, Man, 6-O-MeMan, and Xyl, with compositions Man8–9Xyl1–2Me3GlcNAc2. The present study is the first report of N-glycans with the terminal Xyl attached to the 6-mannose branch of the 6-antenna and to the 3-oxygen of the penultimate (core) GlcNAc. Another novel finding was that all four glycans contain three O-methylmannose residues in positions that have never been reported before. Although it is known that some lower organisms are able to methylate terminal monosaccharides in glycans, the present study on Porphyridium sp. is the first describing an organism that is able to methylate non-terminal mannose residues. This study will thus contribute to understanding of N-glycosylation in algae and might shed light on the evolutionary development from prokaryotes to multicellular organisms. It also may contribute to our understanding of the red algae polysaccharide formation. The additional importance of this research lies in its potential for biotechnological applications, especially in evaluating the use of microalgae as cell factories for the production of therapeutic proteins.
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microorganisms and microalgae as sources of pigments for food use a scientific oddity or an industrial reality
Trends in Food Science and Technology, 2005Co-Authors: Laurent Dufosse, Shoshana Arad, Patrick Galaup, A Yaron, P J Blanc, Kotamballi Chidambara N Murthy, G A RavishankarAbstract:Pigments producing microorganisms and microalgae are quite common in Nature. However, there is a long way from the Petri dish to the market place. Five productions, using Monascus, Penicillium, Dunaliella, Haematococcus and Porphyridium, are discussed. Some companies invested a lot of money as any combination of new source and/or new pigment drives a lot of experimental work, process optimization, toxicological studies and regulatory issues. Time will tell whether investments were cost-effective. Future trends involve combinatorial engineering and production of niche pigments not found in plants.
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antioxidant activity of the polysaccharide of the red microalga Porphyridium sp
Journal of Applied Phycology, 2005Co-Authors: Tehila Tanninspitz, Margalit Bergman, Dorit Vanmoppes, Shlomo Grossman, Shoshana AradAbstract:The cells of the red microalga Porphyridium UTEX 637 are encapsulated within a sulfated polysaccharide whose external part (i.e., the soluble fraction) dissolves into the medium. It is thought that the main function of the polysaccharide is to protect the algal cells from the extreme environmental conditions, such as drought and high light, prevailing in their native sea-sand habitat. In this study, we evaluated the antioxidant properties of the water-soluble polysaccharide of Porphyridium sp. by determining the ability of a polysaccharide solution to inhibit: (1) autooxidation of linoleic acid, as determined by the standard thiobarbituric acid (TBA) and ferrous oxidation (FOX) assays; and (2) oxidative damage to 3T3 cells as determined by the dichlorofluorescein (DCFH) assay. In all three assays, the polysaccharide inhibited oxidative damage in a dose-dependent manner. Antioxidant activity was also exhibited by fractions of the polysaccharide obtained by sonication followed by separation on a reverse-phase HPLC with a C8 semi-preparative column. It is suggested that the antioxidant activity of the sulfated polysaccharide protects the alga against reactive oxygen species produced under high solar irradiation, possibly by scavenging the free radicals produced in the cell under stress conditions and transporting them from the cell to the medium.
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a glycoprotein noncovalently associated with cell wall polysaccharide of the red microalga Porphyridium sp rhodophyta 1
Journal of Phycology, 2004Co-Authors: Roshan P Shrestha, Yacob Weinstein, Dudy Barzvi, Shoshana AradAbstract:The cells of the red microalga Porphyridium sp. (UTEX 637) are encapsulated in a cell wall of a negatively charged mucilaginous polysaccharide complex composed of 10 different sugars, sulfate, and proteins. In this work, we studied the proteins associated with the cell-wall polysaccharide. A number of noncovalently associated proteins were resolved by SDS-PAGE, but no covalently bound proteins were detected. The most prominent protein detected was a 66-kDa glycoprotein consisting of a polypeptide of approximately 58 kDa and a glycan moiety of approximately 8 kDa containing N-linked terminal mannose. In size-exclusion chromatography, the 66-kDa protein was coeluted with the polysaccharide and could be separated from the polysaccharide only after denaturation of the protein, indicating that the 66-kDa protein was tightly bound to the polysaccharide. Western blot analysis revealed that the 66-kDa protein was specific to Porphyridium sp. and P. cruentum, because it was not detected in the other species of red microalgae examined. Indirect immunofluorescence assay confirmed the location of the protein in the algal cell wall. The sequence of cDNA clone encoding the 66-kDa glycoprotein, detected in our in-house expressed sequence tag database of Porphyridium sp., revealed that this is a novel protein with no similarity to any protein in the public domain databases and our in-house expressed sequence tag database of the red microalga Rhodella reticulata. The 66-kDa protein bound polysaccharides from red algae but not from those of other origins tested. Possible roles of the 66-kDa protein in the biosynthesis of the polysaccharide are discussed.
Aulia Citra Islami 141411131066 - One of the best experts on this subject based on the ideXlab platform.
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MANAJEMEN KULTUR MIKROALGA Porphyridium cruentum PADA SKALA LABORATORIUM DAN SKALA INTERMEDIET DI BALAI BESAR PERIKANAN BUDIDAYA AIR PAYAU, JEPARA JAWA TENGAH
Fakultas Perikanan dan Kelautan, 2017Co-Authors: Aulia Citra Islami 141411131066Abstract:Mikroalga Porphyridium cruentum merupakan salah satu pakan alami yang dapat dimanfaatkan dalam bidang industri, kosmetik, pangan, pharmaceutical dan nuetraceutical. Porphyridium cruentum mengandung pigmen fikoeritrin. Pigmen fikoeritrin dapat digunakan untuk pewarna makanan dan pakan alami pada larva ikan hias. Tujuan dari Praktek Kerja Lapang ini adalah untuk mempelajari manajemen kultur mikroalga Porphyridium cruentum pada skala laboratorium dan skala intermediet, faktor-faktor yang perlu diperhatikan dan hambatan yang muncul pada proses kultur Porphyridium cruentum. Metode kerja yang digunakan dalam pelaksanaan Praktek Kerja Lapang adalah metode deskriptif. Data yang diambil berupa data primer serta data sekunder. Pengambilan data dilakukan dengan cara observasi, wawancara, partisipasi aktif, serta studi pustaka. Kegiatan Praktek Kerja Lapang ini dilaksanakan di Balai Besar Perikanan Budidaya Air Payau, Jepara , Kecamatan Jepara, Kabupaten Jepara, Provinsi Jawa Tengah pada tanggal 20 Januari sampai dengan 20 Februari 2017. Kultur Porphyridium cruentum di Balai Besar Perikanan Budidaya Air Payau Jepara dilakukan pada skala laboratorium dan intermediet. Kultur skala laboratorium menggunakan pupuk Walne pro analisis sedangkan pada kultur skala intermediet menggunakan pupuk Walne teknis. Kultur skala laboratorium mengalami puncak kepadatan 4,17 x 106 pada hari keenam. Pada skala intermediet puncak kepadatan terjadi pada hari kelima dengan populasi 1,356 x 106. Hambatan yang muncul kultur Porphyridium cruentum adalah kondisi cuaca yang tidak menentu menyebabkan tingkat pertumbuhan yang tidak dapat tumbuh dengan optimal
Wahju Tjahjaningsih - One of the best experts on this subject based on the ideXlab platform.
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manajemen pasca panen kultur mikroalga Porphyridium cruentum pada skala laboratorium dan skala intermediet di balai besar perikanan budidaya air payau jepara jawa tengah
Journal of Aquaculture and Fish Health, 2019Co-Authors: Ayu Dyah Amini Putri, Wahju TjahjaningsihAbstract:Porphyridium cruentum merupakan salah satu jenis mikroalga dari kelas alga merah yang dapat memproduksi polisakarida dan mengandung beberapa pigmen. Pigmen yang terkandung di dalam P. cruentum memberikan kontribusi yang besar sebagai pewarna makanan dan pakan alami pada larva ikan. Salah satu pigmen yang terdapat pada P. cruentum adalah fikoeritrin. Tujuan praktek kerja lapang ini adalah mengetahui informasi, keterampilan lapangan dan masalah apa saja yang ada tentang manajemen pasca panen kultur mikroalga Porphyridium cruentum pada skala laboratorium dan skala intermediet di BBPBAP Jepara. Praktek Kerja Lapang ini telah dilaksanakan di Balai Besar Perikanan Budidaya Air Payau Jepara, Jawa Tengah pada tanggal 20 Januari - 20 Februari 2017. Metode kerja yang digunakan dalam praktek kerja lapang ini adalah metode deskriptif atau penguraian empiris dengan pendekatan kualitatif. Pengambilan data dilakukan dengan partisipasi aktif, wawancara, observasi dan studi pustaka. Kegiatan yang dilakukan selama praktek kerja lapang adalah proses sterilisasi alat dan bahan, mengkultur mikroalga, menghitung kepadatan mikroalga, memanen mikroalga, mengemas mikroalga, serta menganalisis kelayakan usaha. Berdasarkan perhitungan yang dilakukan, diperoleh pendapatan per siklus sebesar Rp14.760.000,00, Revenue Cost Ratio (R/C) adalah sebesar 1.835. Break Even Point (BEP) skala laboratorium sebesar 251.403 liter bibit, skala intermediet sebesar 12.570 liter bibit Payback period (PP) yang adalah 3.174 tahun atau 38.1 bulan
Yoram Tekoah - One of the best experts on this subject based on the ideXlab platform.
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genes involved in the endoplasmic reticulum n glycosylation pathway of the red microalga Porphyridium sp a bioinformatic study
International Journal of Molecular Sciences, 2014Co-Authors: Oshrat Levyontman, Merav Fisher, Yoram Shotland, Yacob Weinstein, Yoram Tekoah, Shoshana AradAbstract:N-glycosylation is one of the most important post-translational modifications that influence protein polymorphism, including protein structures and their functions. Although this important biological process has been extensively studied in mammals, only limited knowledge exists regarding glycosylation in algae. The current research is focused on the red microalga Porphyridium sp., which is a potentially valuable source for various applications, such as skin therapy, food, and pharmaceuticals. The enzymes involved in the biosynthesis and processing of N-glycans remain undefined in this species, and the mechanism(s) of their genetic regulation is completely unknown. In this study, we describe our pioneering attempt to understand the endoplasmic reticulum N-Glycosylation pathway in Porphyridium sp., using a bioinformatic approach. Homology searches, based on sequence similarities with genes encoding proteins involved in the ER N-glycosylation pathway (including their conserved parts) were conducted using the TBLASTN function on the algae DNA scaffold contigs database. This approach led to the identification of 24 encoded-genes implicated with the ER N-glycosylation pathway in Porphyridium sp. Homologs were found for almost all known N-glycosylation protein sequences in the ER pathway of Porphyridium sp.; thus, suggesting that the ER-pathway is conserved; as it is in other organisms (animals, plants, yeasts, etc.).
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unique n glycan moieties of the 66 kda cell wall glycoprotein from the red microalga Porphyridium sp
Journal of Biological Chemistry, 2011Co-Authors: Oshrat Levyontman, Shoshana Arad, David Harvey, Thomas B Parsons, Antony J Fairbanks, Yoram TekoahAbstract:We report here the structural determination of the N-linked glycans in the 66-kDa glycoprotein, part of the unique sulfated complex cell wall polysaccharide of the red microalga Porphyridium sp. Structures were elucidated by a combination of normal phase/reverse phase HPLC, positive ion MALDI-TOF MS, negative ion electrospray ionization, and MS/MS. The sugar moieties of the glycoprotein consisted of at least four fractions of N-linked glycans, each composed of the same four monosaccharides, GlcNAc, Man, 6-O-MeMan, and Xyl, with compositions Man8–9Xyl1–2Me3GlcNAc2. The present study is the first report of N-glycans with the terminal Xyl attached to the 6-mannose branch of the 6-antenna and to the 3-oxygen of the penultimate (core) GlcNAc. Another novel finding was that all four glycans contain three O-methylmannose residues in positions that have never been reported before. Although it is known that some lower organisms are able to methylate terminal monosaccharides in glycans, the present study on Porphyridium sp. is the first describing an organism that is able to methylate non-terminal mannose residues. This study will thus contribute to understanding of N-glycosylation in algae and might shed light on the evolutionary development from prokaryotes to multicellular organisms. It also may contribute to our understanding of the red algae polysaccharide formation. The additional importance of this research lies in its potential for biotechnological applications, especially in evaluating the use of microalgae as cell factories for the production of therapeutic proteins.
Oshrat Levyontman - One of the best experts on this subject based on the ideXlab platform.
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genes involved in the endoplasmic reticulum n glycosylation pathway of the red microalga Porphyridium sp a bioinformatic study
International Journal of Molecular Sciences, 2014Co-Authors: Oshrat Levyontman, Merav Fisher, Yoram Shotland, Yacob Weinstein, Yoram Tekoah, Shoshana AradAbstract:N-glycosylation is one of the most important post-translational modifications that influence protein polymorphism, including protein structures and their functions. Although this important biological process has been extensively studied in mammals, only limited knowledge exists regarding glycosylation in algae. The current research is focused on the red microalga Porphyridium sp., which is a potentially valuable source for various applications, such as skin therapy, food, and pharmaceuticals. The enzymes involved in the biosynthesis and processing of N-glycans remain undefined in this species, and the mechanism(s) of their genetic regulation is completely unknown. In this study, we describe our pioneering attempt to understand the endoplasmic reticulum N-Glycosylation pathway in Porphyridium sp., using a bioinformatic approach. Homology searches, based on sequence similarities with genes encoding proteins involved in the ER N-glycosylation pathway (including their conserved parts) were conducted using the TBLASTN function on the algae DNA scaffold contigs database. This approach led to the identification of 24 encoded-genes implicated with the ER N-glycosylation pathway in Porphyridium sp. Homologs were found for almost all known N-glycosylation protein sequences in the ER pathway of Porphyridium sp.; thus, suggesting that the ER-pathway is conserved; as it is in other organisms (animals, plants, yeasts, etc.).
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unique n glycan moieties of the 66 kda cell wall glycoprotein from the red microalga Porphyridium sp
Journal of Biological Chemistry, 2011Co-Authors: Oshrat Levyontman, Shoshana Arad, David Harvey, Thomas B Parsons, Antony J Fairbanks, Yoram TekoahAbstract:We report here the structural determination of the N-linked glycans in the 66-kDa glycoprotein, part of the unique sulfated complex cell wall polysaccharide of the red microalga Porphyridium sp. Structures were elucidated by a combination of normal phase/reverse phase HPLC, positive ion MALDI-TOF MS, negative ion electrospray ionization, and MS/MS. The sugar moieties of the glycoprotein consisted of at least four fractions of N-linked glycans, each composed of the same four monosaccharides, GlcNAc, Man, 6-O-MeMan, and Xyl, with compositions Man8–9Xyl1–2Me3GlcNAc2. The present study is the first report of N-glycans with the terminal Xyl attached to the 6-mannose branch of the 6-antenna and to the 3-oxygen of the penultimate (core) GlcNAc. Another novel finding was that all four glycans contain three O-methylmannose residues in positions that have never been reported before. Although it is known that some lower organisms are able to methylate terminal monosaccharides in glycans, the present study on Porphyridium sp. is the first describing an organism that is able to methylate non-terminal mannose residues. This study will thus contribute to understanding of N-glycosylation in algae and might shed light on the evolutionary development from prokaryotes to multicellular organisms. It also may contribute to our understanding of the red algae polysaccharide formation. The additional importance of this research lies in its potential for biotechnological applications, especially in evaluating the use of microalgae as cell factories for the production of therapeutic proteins.
