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Kirsten Heimann - One of the best experts on this subject based on the ideXlab platform.
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First outdoor cultivation of the N2-fixing cyanobacterium Tolypothrix sp. in low-cost suspension and biofilm systems in tropical Australia
Journal of Applied Phycology, 2015Co-Authors: Chander Velu, Carlos Alvarez-roa, Samuel Cirés, Kirsten HeimannAbstract:Tropical N2-fixing cyanobacteria offer an attractive alternative for production of biomass and bioproducts with potentially low cultivation and harvesting costs. The present study evaluated the biomass productivity of the N2-fixing cyanobacterium Tolypothrix sp. NQAIF319 grown in nitrogen-free medium in outdoor suspension and biofilm prototype cultivation systems in tropical Australia (Queensland). One-week cycles yielded maximum biomass productivities—estimated based on ground area occupied by single systems—of 45–49 g dry weight m−2 day−1 (suspension) and 1.0–1.2 g dry weight m−2 day−1 (biofilm) with minimal biological contamination (Tolypothrix sp. biomass representing 94–98 % of the photosynthetic community). Moderate productivities of the pigments phycocyanin/phycoerythrin (0.1–2.8 g m−2 day−1), fatty acids (0.1–2.0 g m−2 day−1), and nitrogen stored in the biomass (0.1–5.9 g m−2 day−1) were reached in biofilm and suspension systems, respectively, opening avenues for production of low-value commodities with potentially big markets (nitrogen-rich biofertilizers and aquaculture feed) and higher-value chemicals (phycobiliproteins and fatty acids). Simulated multi-system arrangements yielded theoretical overall areal productivities four to six times lower than those in single systems thus highlighting the need for future tests fine-tuning inter-system separation to minimize shadowing while maximizing the efficiency in land use in larger-scale production plants. Biofilm and self-flocculated biomass showed 80-fold and 53-fold reduced extracellular-water contents compared to suspension cultures, respectively, which will need to be considered for techno-economic and water/carbon footprint evaluation of each of the possible bioproduct synthesis pathways. In conclusion, the flexible and simple prototypes developed together with the good properties of Tolypothrix sp. represent a promising platform for low-cost production of cyanobacterial bioproducts in tropical regions using low nitrogen-containing water sources.
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First outdoor cultivation of the N_2-fixing cyanobacterium Tolypothrix sp. in low-cost suspension and biofilm systems in tropical Australia
Journal of Applied Phycology, 2015Co-Authors: Chinnathambi Velu, Carlos Alvarez-roa, Samuel Cirés, Kirsten HeimannAbstract:Tropical N_2-fixing cyanobacteria offer an attractive alternative for production of biomass and bioproducts with potentially low cultivation and harvesting costs. The present study evaluated the biomass productivity of the N_2-fixing cyanobacterium Tolypothrix sp. NQAIF319 grown in nitrogen-free medium in outdoor suspension and biofilm prototype cultivation systems in tropical Australia (Queensland). One-week cycles yielded maximum biomass productivities—estimated based on ground area occupied by single systems—of 45–49 g dry weight m^−2 day^−1 (suspension) and 1.0–1.2 g dry weight m^−2 day^−1 (biofilm) with minimal biological contamination ( Tolypothrix sp. biomass representing 94–98 % of the photosynthetic community). Moderate productivities of the pigments phycocyanin/phycoerythrin (0.1–2.8 g m^−2 day^−1), fatty acids (0.1–2.0 g m^−2 day^−1), and nitrogen stored in the biomass (0.1–5.9 g m^−2 day^−1) were reached in biofilm and suspension systems, respectively, opening avenues for production of low-value commodities with potentially big markets (nitrogen-rich biofertilizers and aquaculture feed) and higher-value chemicals (phycobiliproteins and fatty acids). Simulated multi-system arrangements yielded theoretical overall areal productivities four to six times lower than those in single systems thus highlighting the need for future tests fine-tuning inter-system separation to minimize shadowing while maximizing the efficiency in land use in larger-scale production plants. Biofilm and self-flocculated biomass showed 80-fold and 53-fold reduced extracellular-water contents compared to suspension cultures, respectively, which will need to be considered for techno-economic and water/carbon footprint evaluation of each of the possible bioproduct synthesis pathways. In conclusion, the flexible and simple prototypes developed together with the good properties of Tolypothrix sp. represent a promising platform for low-cost production of cyanobacterial bioproducts in tropical regions using low nitrogen-containing water sources.
Jean Houmard - One of the best experts on this subject based on the ideXlab platform.
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Regulated expression of glutamyl-tRNA synthetase is directed by a mobile genetic element in the cyanobacterium Tolypothrix sp. PCC 7601.
Molecular microbiology, 2006Co-Authors: Ignacio Luque, Gérald Zabulon, Alfonso Andújar, Lin Jia, Nicole Tandeau De Marsac, Enrique Flores, Jean HoumardAbstract:The genome of Tolypothrix sp. PCC 7601 carries two copies of a novel insertion sequence, ISTosp1. One of the two copies is located upstream of the gene encoding glutamyl-tRNA synthetase, an enzyme playing a key role in protein and pigment synthesis. The tnpA gene of the IS element and gltX were co-transcribed and their expression was transiently upregulated upon retrieval of the ammonium source irrespective of whether nitrate or no nitrogen source were available. The second copy is also transcribed and shows a similar regulatory pattern. Structural elements of the promoter (-10 and -35 sequences) directing the expression of the tnpA-gltX operon have been localized within the IS. Regulatory sequences involving the NtcA transcription factor in the control of tnpA-gltX expression were found both within and in sequences upstream of the insertion element. The expression of gltX in a closely related cyanobacterium, Nostoc sp. PCC 7120, which lacks the insertion upstream of gltX, decreased upon ammonium retrieval, a regulatory pattern that markedly differs from that observed in Tolypothrix sp. PCC 7601. ISTosp1 constitutes a good example of how cells can make use of a transposable element to evolve an original regulatory mechanism.
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Immunolocalization of NblA, a protein involved in phycobilisome turnover, during heterocyst differentiation in cyanobacteria.
Microbiology (Reading England), 2004Co-Authors: Jesús A G Ochoa De Alda, Christiane Lichtlé, Jean-claude Thomas, Jean HoumardAbstract:In unicellular non-diazotrophic cyanobacteria, NblA is a small polypeptide required for phycobilisome degradation during macronutrient limitation. In the filamentous N(2)-fixing Tolypothrix sp., a nblA gene (nblAI) lies upstream of the cpeBA operon that encodes phycoerythrin apoproteins. Using a specific anti-NblAI antibody it was found that in strains of Tolypothrix sp. NblAI abundance increases under nitrogen-limiting conditions but the protein is also present in cells grown in nitrogen-replete medium. Gold immunolabelling experiments showed that, upon a nitrogen shift-down, NblAI is preferentially located in the differentiated heterocysts, where O(2) evolution has to be shut off for nitrogenase to operate. The results lead to the proposal that NblAI is a necessary 'cofactor' but not the triggering factor that governs phycobilisome degradation in Tolypothrix sp.
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The NblAI protein from the filamentous cyanobacterium Tolypothrix PCC 7601: regulation of its expression and interactions with phycobilisome components.
Molecular microbiology, 2003Co-Authors: Ignacio Luque, Jesús A G Ochoa De Alda, Jean-claude Thomas, Catherine Richaud, Gérald Zabulon, Jean HoumardAbstract:Summary Cyanobacteria respond to changes in light or nutrient availability by modifications in their photosynthetic light harvesting antenna. In unicellular cyanobacteria a small polypeptide (NblA) is required for phycobilisome degradation following environmental stresses. In the filamentous strain Tolypothrix sp. PCC 7601 the nblAI gene, encoding a NblA homologue, is located upstream of the operon coding for phycoerythrin (cpeBA). The nblAI transcripts all originate from a single transcription start point; their intracellular levels vary according to nitrogen regimes but not with light spectral quality. Using recombinant His-tagged NblAI protein, we found that in vitro NblAI has affinity for both phycocyanin and phycoerythrin subunits from Tolypothrix sp. PCC 7601, but not for allophycocyanin from this cyanobacterium or for phycobiliproteins from other cyanobacterial species. We also observed that although nblAI is mainly expressed under nitrogen starvation, NblAI polypeptides are always present in the cell; a significant portion of them co-purify with phycobilisome preparations but only if cells were grown under red light. Our data indicate that NblAI attaches to the phycobilisomes even under non-inducing conditions and suggest a preferential affinity of NblAI for phycocyanin.
Ignacio Luque - One of the best experts on this subject based on the ideXlab platform.
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Regulated expression of glutamyl-tRNA synthetase is directed by a mobile genetic element in the cyanobacterium Tolypothrix sp. PCC 7601.
Molecular microbiology, 2006Co-Authors: Ignacio Luque, Gérald Zabulon, Alfonso Andújar, Lin Jia, Nicole Tandeau De Marsac, Enrique Flores, Jean HoumardAbstract:The genome of Tolypothrix sp. PCC 7601 carries two copies of a novel insertion sequence, ISTosp1. One of the two copies is located upstream of the gene encoding glutamyl-tRNA synthetase, an enzyme playing a key role in protein and pigment synthesis. The tnpA gene of the IS element and gltX were co-transcribed and their expression was transiently upregulated upon retrieval of the ammonium source irrespective of whether nitrate or no nitrogen source were available. The second copy is also transcribed and shows a similar regulatory pattern. Structural elements of the promoter (-10 and -35 sequences) directing the expression of the tnpA-gltX operon have been localized within the IS. Regulatory sequences involving the NtcA transcription factor in the control of tnpA-gltX expression were found both within and in sequences upstream of the insertion element. The expression of gltX in a closely related cyanobacterium, Nostoc sp. PCC 7120, which lacks the insertion upstream of gltX, decreased upon ammonium retrieval, a regulatory pattern that markedly differs from that observed in Tolypothrix sp. PCC 7601. ISTosp1 constitutes a good example of how cells can make use of a transposable element to evolve an original regulatory mechanism.
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The NblAI protein from the filamentous cyanobacterium Tolypothrix PCC 7601: regulation of its expression and interactions with phycobilisome components.
Molecular microbiology, 2003Co-Authors: Ignacio Luque, Jesús A G Ochoa De Alda, Jean-claude Thomas, Catherine Richaud, Gérald Zabulon, Jean HoumardAbstract:Summary Cyanobacteria respond to changes in light or nutrient availability by modifications in their photosynthetic light harvesting antenna. In unicellular cyanobacteria a small polypeptide (NblA) is required for phycobilisome degradation following environmental stresses. In the filamentous strain Tolypothrix sp. PCC 7601 the nblAI gene, encoding a NblA homologue, is located upstream of the operon coding for phycoerythrin (cpeBA). The nblAI transcripts all originate from a single transcription start point; their intracellular levels vary according to nitrogen regimes but not with light spectral quality. Using recombinant His-tagged NblAI protein, we found that in vitro NblAI has affinity for both phycocyanin and phycoerythrin subunits from Tolypothrix sp. PCC 7601, but not for allophycocyanin from this cyanobacterium or for phycobiliproteins from other cyanobacterial species. We also observed that although nblAI is mainly expressed under nitrogen starvation, NblAI polypeptides are always present in the cell; a significant portion of them co-purify with phycobilisome preparations but only if cells were grown under red light. Our data indicate that NblAI attaches to the phycobilisomes even under non-inducing conditions and suggest a preferential affinity of NblAI for phycocyanin.
Siba Prasad Adhikary - One of the best experts on this subject based on the ideXlab platform.
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estimation of growth and exopolysaccharide production by two soil cyanobacteria scytonema tolypothrichoides and Tolypothrix bouteillei as determined by cultivation in irradiance and temperature crossed gradients
Engineering in Life Sciences, 2019Co-Authors: Jana Kviderova, Dhanesh Kumar, Jaromir Lukavský, Petr Kastanek, Siba Prasad AdhikaryAbstract:Two filamentous cyanobacteria of the genera Scytonema and Tolypothrix were reported to be effective for stabilizing soil in arid areas due to the production of significant amounts of extracellular polysaccharides (EPS). These EPS may also have applications in the biotechnology industry. Therefore, two cyanobacterial species, Scytonema tolypothrichoides and Tolypothrix bouteillei were examined using crossed gradients of temperature (8-40°C) and irradiance (3-21 W m-2) to identify their temperature and irradiance optima for maximum biomass and EPS production. According to their reported temperature requirements, both strains were considered mesophilic. The optimum growth range of temperature in S. tolypothrichoides (27 to 34°C) was higher than T. bouteillei (22-32°C). The optimum irradiance range for growth of S. tolypothrichoides (9-13 W m-2) was slightly lower than T. bouteillei (7-18 W m-2). Maximum EPS production by S. tolypothrichoides occurred at similar temperatures (28-34°C) as T. bouteillei (27-34°C), both slightly higher than for maximum growth. The optimum irradiance range for EPS production was comparable to that for growth in S. tolypotrichoides (8-13 W m-2), and slightly lower in T. bouteillei (7-17 W m-2). The Redundancy Analysis confirmed that temperature was the most important controlling factor and protocols for field applications or for mass cultivation can now be developed.
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Diversity of Cyanobacteria in Biological Crusts on Arid Soils in the Eastern Region of India and their Molecular Phylogeny
Current Science, 2016Co-Authors: Dhanesh Kumar, Petr Kastanek, Siba Prasad AdhikaryAbstract:The biological crusts on lateritic soils, red soils and mine-waste burdened soils in the eastern region of India covering a transect of about 800 km were principally composed of sheathed cyanobacteria of the genera Scytonema, Tolypothrix and Lyngbya along with few other species of Cylindrospermum, Nostoc , Calothrix and Fischerella . Molecular phylogeny based on 16S rRNA gene sequence of these cyanobacteria along with those occurring in different habitats of four different continents formed a distinct clade, however, were clustered close to other filamentous cyanobacteria.
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Draft Genome Sequence of Bioactive-Compound-Producing Cyanobacterium Tolypothrix campylonemoides Strain VB511288.
Genome announcements, 2015Co-Authors: Subhadeep Das, Siba Prasad Adhikary, Mathu Malar Chandrababunaidu, Deeksha Singh, Akash Gupta, Madhavi Madduluri, Sucheta TripathyAbstract:We report here the draft genome sequence of Tolypothrix campylonemoides VB511288, isolated from building facades in Santiniketan, India. The members of this genus produce several compounds of commercial importance. The draft assembly is 10,627,177 bases in 135 scaffolds, and it contains 7,886 protein-coding genes, 994 pseudogenes, 18 rRNA genes, and 76 tRNA genes.
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Cyanobacteria in biofilms on stone temples of Bhubaneswar, Eastern India
Algological Studies, 2015Co-Authors: Siba Prasad Adhikary, Nitin Keshari, Clara Urzì, Roberto De PhilippisAbstract:The exterior facades of several stone temples of Bhubaneswar (eastern India), built during the 6th to 13th centuries, are now covered with blackish-brown biofilms dominated by cyanobacteria. The architectural carvings show various degrees of deterioration of lithic faces underneath the biofilms, indicating the contribution of these phototrophic microorganisms to this process. A total of 17 species of cyanobacteria, belonging to the genera Gloeocapsa, Gloeocapsopsis, Porphyrosiphon, Leptolyngbya, Lyngbya, Phormidium, Nostoc, Scytonema, Tolypothrix, Hassallia and Stigonema were found in biofilms during the hot months of the tropical summers. The organisms were identified on the basis of their morphological features and those species that were isolated in pure culture were taxonomically validated by 16S rRNA gene sequencing. The temperature at the exterior of these stone monuments exceeds 60°C, especially during summer, coupled with extreme dryness. Consequently, only cyanobacteria are able to form biofilms. In contrast, during the rainy season, biofilms contained 25 additional cyanobacteria species belonging to the genera Cyanosarcina, Gloeocapsopsis, Phormidium, Pseudophormidium, Schizothrix, Lyngbya, Plectonema, Nostoc, Scytonema, Tolypothrix, Dichothrix and Calothrix together with the green alga Chlorella sphaerica.
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Draft Genome Sequence of Tolypothrix boutellei Strain VB521301
Genome announcements, 2015Co-Authors: Mathu Malar Chandrababunaidu, Siba Prasad Adhikary, Deeksha Singh, Diya Sen, Sushma Bhan, Subhadeep Das, Akash Gupta, Sucheta TripathyAbstract:We report here the draft genome sequence of the filamentous nitrogen-fixing cyanobacterium Tolypothrix boutellei strain VB521301. The organism is lipid rich and hydrophobic and produces polyunsaturated fatty acids which can be harnessed for industrial purpose. The draft genome sequence assembled into 11,572,263 bp with 70 scaffolds and 7,777 protein coding genes.
Gérald Zabulon - One of the best experts on this subject based on the ideXlab platform.
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Regulated expression of glutamyl-tRNA synthetase is directed by a mobile genetic element in the cyanobacterium Tolypothrix sp. PCC 7601.
Molecular microbiology, 2006Co-Authors: Ignacio Luque, Gérald Zabulon, Alfonso Andújar, Lin Jia, Nicole Tandeau De Marsac, Enrique Flores, Jean HoumardAbstract:The genome of Tolypothrix sp. PCC 7601 carries two copies of a novel insertion sequence, ISTosp1. One of the two copies is located upstream of the gene encoding glutamyl-tRNA synthetase, an enzyme playing a key role in protein and pigment synthesis. The tnpA gene of the IS element and gltX were co-transcribed and their expression was transiently upregulated upon retrieval of the ammonium source irrespective of whether nitrate or no nitrogen source were available. The second copy is also transcribed and shows a similar regulatory pattern. Structural elements of the promoter (-10 and -35 sequences) directing the expression of the tnpA-gltX operon have been localized within the IS. Regulatory sequences involving the NtcA transcription factor in the control of tnpA-gltX expression were found both within and in sequences upstream of the insertion element. The expression of gltX in a closely related cyanobacterium, Nostoc sp. PCC 7120, which lacks the insertion upstream of gltX, decreased upon ammonium retrieval, a regulatory pattern that markedly differs from that observed in Tolypothrix sp. PCC 7601. ISTosp1 constitutes a good example of how cells can make use of a transposable element to evolve an original regulatory mechanism.
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The NblAI protein from the filamentous cyanobacterium Tolypothrix PCC 7601: regulation of its expression and interactions with phycobilisome components.
Molecular microbiology, 2003Co-Authors: Ignacio Luque, Jesús A G Ochoa De Alda, Jean-claude Thomas, Catherine Richaud, Gérald Zabulon, Jean HoumardAbstract:Summary Cyanobacteria respond to changes in light or nutrient availability by modifications in their photosynthetic light harvesting antenna. In unicellular cyanobacteria a small polypeptide (NblA) is required for phycobilisome degradation following environmental stresses. In the filamentous strain Tolypothrix sp. PCC 7601 the nblAI gene, encoding a NblA homologue, is located upstream of the operon coding for phycoerythrin (cpeBA). The nblAI transcripts all originate from a single transcription start point; their intracellular levels vary according to nitrogen regimes but not with light spectral quality. Using recombinant His-tagged NblAI protein, we found that in vitro NblAI has affinity for both phycocyanin and phycoerythrin subunits from Tolypothrix sp. PCC 7601, but not for allophycocyanin from this cyanobacterium or for phycobiliproteins from other cyanobacterial species. We also observed that although nblAI is mainly expressed under nitrogen starvation, NblAI polypeptides are always present in the cell; a significant portion of them co-purify with phycobilisome preparations but only if cells were grown under red light. Our data indicate that NblAI attaches to the phycobilisomes even under non-inducing conditions and suggest a preferential affinity of NblAI for phycocyanin.
