The Experts below are selected from a list of 3102 Experts worldwide ranked by ideXlab platform
Thankgod E Ebenezer - One of the best experts on this subject based on the ideXlab platform.
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metabolic quirks and the colourful history of the euglena gracilis secondary Plastid
New Phytologist, 2020Co-Authors: Anna Novak M G Vanclova, Martin Zoltner, Steven L Kelly, Petr Soukal, Kristina Zahonova, Zoltan Fussy, Thankgod E EbenezerAbstract:Euglena spp. are phototrophic flagellates with considerable ecological presence and impact. Euglena gracilis harbours secondary green Plastids, but an incompletely characterised proteome precludes accurate understanding of both Plastid function and evolutionary history. Using subcellular fractionation, an improved sequence database and MS we determined the composition, evolutionary relationships and hence predicted functions of the E. gracilis Plastid proteome. We confidently identified 1345 distinct Plastid protein groups and found that at least 100 proteins represent horizontal acquisitions from organisms other than green algae or prokaryotes. Metabolic reconstruction confirmed previously studied/predicted enzymes/pathways and provided evidence for multiple unusual features, including uncoupling of carotenoid and phytol metabolism, a limited role in amino acid metabolism, and dual sets of the SUF pathway for FeS cluster assembly, one of which was acquired by lateral gene transfer from Chlamydiae. Plastid paralogues of trafficking-associated proteins potentially mediating fusion of transport vesicles with the outermost Plastid Membrane were identified, together with derlin-related proteins, potential translocases across the middle Membrane, and an extremely simplified TIC complex. The Euglena Plastid, as the product of many genomes, combines novel and conserved features of metabolism and transport.
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proteome of the secondary Plastid of euglena gracilis reveals metabolic quirks and colourful history
bioRxiv, 2019Co-Authors: Anna Novak M G Vanclova, Martin Zoltner, Petr Soukal, Kristina Zahonova, Thankgod E Ebenezer, Steve Kelly, Z Fuiˆssy, Lacova E Dobakova, Marek EliasAbstract:Abstract Euglena gracilis is a well-studied biotechnologically exploitable phototrophic flagellate harbouring secondary green Plastids. Here we describe its Plastid proteome obtained by high-resolution proteomics. We identified 1,345 candidate Plastid proteins and assigned functional annotations to 774 of them. More than 120 proteins are affiliated neither to the host lineage nor the Plastid ancestor and may represent horizontal acquisitions from various algal and prokaryotic groups. Reconstruction of Plastid metabolism confirms both the presence of previously studied/predicted enzymes/pathways and also provides direct evidence for unusual features of its metabolism including uncoupling of carotenoid and phytol metabolism, a limited role in amino acid metabolism and the presence of two sets of the SUF pathway for FeS cluster assembly. Most significantly, one of these was acquired by lateral gene transfer (LGT) from the chlamydiae. Plastidial paralogs of Membrane trafficking-associated proteins likely mediating a poorly understood fusion of transport vesicles with the outermost Plastid Membrane were identified, as well as derlin-related proteins that potentially act as protein translocases of the middle Membrane, supporting an extremely simplified TIC complex. The proposed innovations may be also linked to specific features of the transit peptide-like regions described here. Hence the Euglena Plastid is demonstrated to be a product of several genomes and to combine novel and conserved metabolism and transport processes.
Agnieszka Mostowska - One of the best experts on this subject based on the ideXlab platform.
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galactolipid deficiency disturbs spatial arrangement of the thylakoid network in arabidopsis thaliana plants
Journal of Experimental Botany, 2019Co-Authors: Radoslaw Mazur, Maciej Garstka, Agnieszka Mostowska, Joanna Szach, Katarzyna Gieczewska, Joanna Wojtowicz, Katarzyna Bednarska, łucja KowalewskaAbstract:The chloroplast thylakoid network is a dynamic structure which, through possible rearrangements, plays a crucial role in regulation of photosynthesis. Although the importance of the main components of the thylakoid Membrane matrix, galactolipids, in the formation of the network of internal Plastid Membrane was found before, the structural role of monogalactosyldiacylglycerol (MGDG) and digalactosylidacylglycerol (DGDG) is still largely unknown. We elucidated detailed structural modifications of the thylakoid Membrane system in Arabidopsis thaliana MGDG- and DGDG-deficient mutants. An altered MGDG/DGDG ratio was structurally reflected by formation of smaller grana, local changes in grana stacking repeat distance, and significant changes in the spatial organization of the thylakoid network compared with wild-type plants. The decrease of the MGDG level impaired the formation of the typical helical grana structure and resulted in a 'helical-dichotomic' arrangement. DGDG deficiency did not affect spatial grana organization but changed the shape of the thylakoid Membrane network in situ from lens like into a flattened shape. Such structural disturbances were accompanied by altered composition of carotenoid and chlorophyll-protein complexes, which eventually led to the decreased photosynthetic efficiency of MGDG- and DGDG-deficient plants.
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three dimensional visualization of the tubular lamellar transformation of the internal Plastid Membrane network during runner bean chloroplast biogenesis
The Plant Cell, 2016Co-Authors: łucja Kowalewska, Radoslaw Mazur, S Suski, Maciej Garstka, Agnieszka MostowskaAbstract:Chloroplast biogenesis is a complex process that is integrated with plant development, leading to fully differentiated and functionally mature Plastids. In this work, we used electron tomography and confocal microscopy to reconstruct the process of structural Membrane transformation during the etioplast-to-chloroplast transition in runner bean (Phaseolus coccineus). During chloroplast development, the regular tubular network of paracrystalline prolamellar bodies (PLBs) and the flattened porous Membranes of prothylakoids develop into the chloroplast thylakoids. Three-dimensional reconstruction is required to provide us with a more complete understanding of this transformation. We provide spatial models of the bean chloroplast biogenesis that allow such reconstruction of the internal Membranes of the developing chloroplast and visualize the transformation from the tubular arrangement to the linear system of parallel lamellae. We prove that the tubular structure of the PLB transforms directly to flat slats, without dispersion to vesicles. We demonstrate that the grana/stroma thylakoid connections have a helical character starting from the early stages of appressed Membrane formation. Moreover, we point out the importance of particular chlorophyll-protein complex components in the Membrane stacking during the biogenesis. The main stages of chloroplast internal Membrane biogenesis are presented in a movie that shows the time development of the chloroplast biogenesis as a dynamic model of this process.
Kristina Zahonova - One of the best experts on this subject based on the ideXlab platform.
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metabolic quirks and the colourful history of the euglena gracilis secondary Plastid
New Phytologist, 2020Co-Authors: Anna Novak M G Vanclova, Martin Zoltner, Steven L Kelly, Petr Soukal, Kristina Zahonova, Zoltan Fussy, Thankgod E EbenezerAbstract:Euglena spp. are phototrophic flagellates with considerable ecological presence and impact. Euglena gracilis harbours secondary green Plastids, but an incompletely characterised proteome precludes accurate understanding of both Plastid function and evolutionary history. Using subcellular fractionation, an improved sequence database and MS we determined the composition, evolutionary relationships and hence predicted functions of the E. gracilis Plastid proteome. We confidently identified 1345 distinct Plastid protein groups and found that at least 100 proteins represent horizontal acquisitions from organisms other than green algae or prokaryotes. Metabolic reconstruction confirmed previously studied/predicted enzymes/pathways and provided evidence for multiple unusual features, including uncoupling of carotenoid and phytol metabolism, a limited role in amino acid metabolism, and dual sets of the SUF pathway for FeS cluster assembly, one of which was acquired by lateral gene transfer from Chlamydiae. Plastid paralogues of trafficking-associated proteins potentially mediating fusion of transport vesicles with the outermost Plastid Membrane were identified, together with derlin-related proteins, potential translocases across the middle Membrane, and an extremely simplified TIC complex. The Euglena Plastid, as the product of many genomes, combines novel and conserved features of metabolism and transport.
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proteome of the secondary Plastid of euglena gracilis reveals metabolic quirks and colourful history
bioRxiv, 2019Co-Authors: Anna Novak M G Vanclova, Martin Zoltner, Petr Soukal, Kristina Zahonova, Thankgod E Ebenezer, Steve Kelly, Z Fuiˆssy, Lacova E Dobakova, Marek EliasAbstract:Abstract Euglena gracilis is a well-studied biotechnologically exploitable phototrophic flagellate harbouring secondary green Plastids. Here we describe its Plastid proteome obtained by high-resolution proteomics. We identified 1,345 candidate Plastid proteins and assigned functional annotations to 774 of them. More than 120 proteins are affiliated neither to the host lineage nor the Plastid ancestor and may represent horizontal acquisitions from various algal and prokaryotic groups. Reconstruction of Plastid metabolism confirms both the presence of previously studied/predicted enzymes/pathways and also provides direct evidence for unusual features of its metabolism including uncoupling of carotenoid and phytol metabolism, a limited role in amino acid metabolism and the presence of two sets of the SUF pathway for FeS cluster assembly. Most significantly, one of these was acquired by lateral gene transfer (LGT) from the chlamydiae. Plastidial paralogs of Membrane trafficking-associated proteins likely mediating a poorly understood fusion of transport vesicles with the outermost Plastid Membrane were identified, as well as derlin-related proteins that potentially act as protein translocases of the middle Membrane, supporting an extremely simplified TIC complex. The proposed innovations may be also linked to specific features of the transit peptide-like regions described here. Hence the Euglena Plastid is demonstrated to be a product of several genomes and to combine novel and conserved metabolism and transport processes.
łucja Kowalewska - One of the best experts on this subject based on the ideXlab platform.
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galactolipid deficiency disturbs spatial arrangement of the thylakoid network in arabidopsis thaliana plants
Journal of Experimental Botany, 2019Co-Authors: Radoslaw Mazur, Maciej Garstka, Agnieszka Mostowska, Joanna Szach, Katarzyna Gieczewska, Joanna Wojtowicz, Katarzyna Bednarska, łucja KowalewskaAbstract:The chloroplast thylakoid network is a dynamic structure which, through possible rearrangements, plays a crucial role in regulation of photosynthesis. Although the importance of the main components of the thylakoid Membrane matrix, galactolipids, in the formation of the network of internal Plastid Membrane was found before, the structural role of monogalactosyldiacylglycerol (MGDG) and digalactosylidacylglycerol (DGDG) is still largely unknown. We elucidated detailed structural modifications of the thylakoid Membrane system in Arabidopsis thaliana MGDG- and DGDG-deficient mutants. An altered MGDG/DGDG ratio was structurally reflected by formation of smaller grana, local changes in grana stacking repeat distance, and significant changes in the spatial organization of the thylakoid network compared with wild-type plants. The decrease of the MGDG level impaired the formation of the typical helical grana structure and resulted in a 'helical-dichotomic' arrangement. DGDG deficiency did not affect spatial grana organization but changed the shape of the thylakoid Membrane network in situ from lens like into a flattened shape. Such structural disturbances were accompanied by altered composition of carotenoid and chlorophyll-protein complexes, which eventually led to the decreased photosynthetic efficiency of MGDG- and DGDG-deficient plants.
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three dimensional visualization of the tubular lamellar transformation of the internal Plastid Membrane network during runner bean chloroplast biogenesis
The Plant Cell, 2016Co-Authors: łucja Kowalewska, Radoslaw Mazur, S Suski, Maciej Garstka, Agnieszka MostowskaAbstract:Chloroplast biogenesis is a complex process that is integrated with plant development, leading to fully differentiated and functionally mature Plastids. In this work, we used electron tomography and confocal microscopy to reconstruct the process of structural Membrane transformation during the etioplast-to-chloroplast transition in runner bean (Phaseolus coccineus). During chloroplast development, the regular tubular network of paracrystalline prolamellar bodies (PLBs) and the flattened porous Membranes of prothylakoids develop into the chloroplast thylakoids. Three-dimensional reconstruction is required to provide us with a more complete understanding of this transformation. We provide spatial models of the bean chloroplast biogenesis that allow such reconstruction of the internal Membranes of the developing chloroplast and visualize the transformation from the tubular arrangement to the linear system of parallel lamellae. We prove that the tubular structure of the PLB transforms directly to flat slats, without dispersion to vesicles. We demonstrate that the grana/stroma thylakoid connections have a helical character starting from the early stages of appressed Membrane formation. Moreover, we point out the importance of particular chlorophyll-protein complex components in the Membrane stacking during the biogenesis. The main stages of chloroplast internal Membrane biogenesis are presented in a movie that shows the time development of the chloroplast biogenesis as a dynamic model of this process.
Martin Zoltner - One of the best experts on this subject based on the ideXlab platform.
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metabolic quirks and the colourful history of the euglena gracilis secondary Plastid
New Phytologist, 2020Co-Authors: Anna Novak M G Vanclova, Martin Zoltner, Steven L Kelly, Petr Soukal, Kristina Zahonova, Zoltan Fussy, Thankgod E EbenezerAbstract:Euglena spp. are phototrophic flagellates with considerable ecological presence and impact. Euglena gracilis harbours secondary green Plastids, but an incompletely characterised proteome precludes accurate understanding of both Plastid function and evolutionary history. Using subcellular fractionation, an improved sequence database and MS we determined the composition, evolutionary relationships and hence predicted functions of the E. gracilis Plastid proteome. We confidently identified 1345 distinct Plastid protein groups and found that at least 100 proteins represent horizontal acquisitions from organisms other than green algae or prokaryotes. Metabolic reconstruction confirmed previously studied/predicted enzymes/pathways and provided evidence for multiple unusual features, including uncoupling of carotenoid and phytol metabolism, a limited role in amino acid metabolism, and dual sets of the SUF pathway for FeS cluster assembly, one of which was acquired by lateral gene transfer from Chlamydiae. Plastid paralogues of trafficking-associated proteins potentially mediating fusion of transport vesicles with the outermost Plastid Membrane were identified, together with derlin-related proteins, potential translocases across the middle Membrane, and an extremely simplified TIC complex. The Euglena Plastid, as the product of many genomes, combines novel and conserved features of metabolism and transport.
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proteome of the secondary Plastid of euglena gracilis reveals metabolic quirks and colourful history
bioRxiv, 2019Co-Authors: Anna Novak M G Vanclova, Martin Zoltner, Petr Soukal, Kristina Zahonova, Thankgod E Ebenezer, Steve Kelly, Z Fuiˆssy, Lacova E Dobakova, Marek EliasAbstract:Abstract Euglena gracilis is a well-studied biotechnologically exploitable phototrophic flagellate harbouring secondary green Plastids. Here we describe its Plastid proteome obtained by high-resolution proteomics. We identified 1,345 candidate Plastid proteins and assigned functional annotations to 774 of them. More than 120 proteins are affiliated neither to the host lineage nor the Plastid ancestor and may represent horizontal acquisitions from various algal and prokaryotic groups. Reconstruction of Plastid metabolism confirms both the presence of previously studied/predicted enzymes/pathways and also provides direct evidence for unusual features of its metabolism including uncoupling of carotenoid and phytol metabolism, a limited role in amino acid metabolism and the presence of two sets of the SUF pathway for FeS cluster assembly. Most significantly, one of these was acquired by lateral gene transfer (LGT) from the chlamydiae. Plastidial paralogs of Membrane trafficking-associated proteins likely mediating a poorly understood fusion of transport vesicles with the outermost Plastid Membrane were identified, as well as derlin-related proteins that potentially act as protein translocases of the middle Membrane, supporting an extremely simplified TIC complex. The proposed innovations may be also linked to specific features of the transit peptide-like regions described here. Hence the Euglena Plastid is demonstrated to be a product of several genomes and to combine novel and conserved metabolism and transport processes.