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Werner E G Muller - One of the best experts on this subject based on the ideXlab platform.
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flexible minerals self assembled calcite Spicules with extreme bending strength
Science, 2013Co-Authors: Werner E G Muller, Filipe Natalio, Tomas P Corrales, Martin Panthofer, Dieter Schollmeyer, Ingo Lieberwirth, Michael Kappl, Hansjurgen Butt, Wolfgang TremelAbstract:Silicatein-α is responsible for the biomineralization of silicates in sponges. We used silicatein-α to guide the self-assembly of calcite "Spicules" similar to the Spicules of the calcareous sponge Sycon sp. The self-assembled Spicules, 10 to 300 micrometers (μm) in length and 5 to 10 μm in diameter, are composed of aligned calcite nanocrystals. The Spicules are initially amorphous but transform into calcite within months, exhibiting unusual growth along [100]. They scatter x-rays like twinned calcite crystals. Whereas natural Spicules evidence brittle failure, the synthetic Spicules show an elastic response, which greatly enhances bending strength. This remarkable feature is linked to a high protein content. With nano-thermogravimetric analysis, we measured the organic content of a single spicule to be 10 to 16%. In addition, the Spicules exhibit waveguiding properties even when they are bent.
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silicateins silicatein interactors and cellular interplay in sponge skeletogenesis formation of glass fiber like Spicules
FEBS Journal, 2012Co-Authors: Xiaohong Wang, Ute Schlosmacher, Heinz C Schroder, Matthias Wiens, Renato Batel, Werner E G MullerAbstract:Biomineralization processes are characterized by controlled deposition of inorganic polymers/minerals mediated by functional groups linked to organic templates. One metazoan taxon, the siliceous sponges, has utilized these principles and even gained the ability to form these polymers/minerals by an enzymatic mechanism using silicateins. Silicateins are the dominant protein species present in the axial canal of the skeletal elements of the siliceous sponges, the Spicules, where they form the axial filament. Silicateins also represent a major part of the organic components of the silica lamellae, which are cylindrically arranged around the axial canal. With the demosponge Suberites domuncula as a model, quantitative enzymatic studies revealed that both the native and the recombinant enzyme display in vitro the same biosilica-forming activity as the enzyme involved in spicule formation in vivo. Monomeric silicatein molecules assemble into filaments via fractal intermediates, which are stabilized by the silicatein-interacting protein silintaphin-1. Besides the silicateins, a silica-degrading enzyme silicase acting as a catabolic enzyme has been identified. Growth of Spicules proceeds in vivo in two directions: first, by axial growth, a process that is controlled by evagination of cell protrusions and mediated by the axial filament-associated silicateins; and second, by appositional growth, which is driven by the extraspicular silicateins, a process that provides the Spicules with their final size and morphology. This radial layer-by-layer accretion is directed by organic cylinders that are formed around the growing spicule and consist of galectin and silicatein. The cellular interplay that controls the morphogenetic processes during spiculogenesis is outlined.
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bio sintering processes in hexactinellid sponges fusion of bio silica in giant basal Spicules from monorhaphis chuni
Journal of Structural Biology, 2009Co-Authors: Werner E G Muller, Zaklina Burghard, Joachim Bill, Xiaohong Wang, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, Matthias WiensAbstract:Abstract The two sponge classes, Hexactinellida and Demospongiae, comprise a skeleton that is composed of siliceous skeletal elements (Spicules). Spicule growth proceeds by appositional layering of lamellae that consist of silica nanoparticles, which are synthesized via the sponge-specific enzyme silicatein. While in demosponges during maturation the lamellae consolidate to a solid rod, the lamellar organization of hexactinellid Spicules largely persists. However, the innermost lamellae, near the spicule core, can also fuse to a solid axial cylinder. Similar to the fusion of siliceous nanoparticles and lamella, in several hexactinellid species individual Spicules unify during sintering-like processes. Here, we study the different stages of a process that we termed bio-sintering, within the giant basal spicule (GBS) of Monorhaphis chuni. During this study, a major GBS protein component (27 kDa) was isolated and analyzed by MALDI-TOF-MS. The sequences were used to isolate and clone the encoding cDNA via degenerate primer PCR. Bioinformatic analyses revealed a significant sequence homology to silicatein. In addition, the native GBS protein was able to mediate bio-silica synthesis in vitro. We conclude that the syntheses of bio-silica in M. chuni, and the subsequent fusion of nanoparticles to lamellae, and finally to Spicules, are enzymatically-driven by a silicatein-like protein. In addition, evidence is now presented that in hexactinellids those fusions involve sintering-like processes.
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axial growth of hexactinellid Spicules formation of cone like structural units in the giant basal Spicules of the hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Xiaohong Wang, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, David Brandt, Jinhe Li, Jaap A Kaandorp, Hermann Gotz, H Duschner, Werner E G MullerAbstract:The glass sponge Monorhaphis chuni (Porifera: Hexactinellida) forms the largest bio-silica structures on Earth; their giant basal Spicules reach sizes of up to 3 m and diameters of 8.5 mm. Previously, it had been shown that the thickness growth proceeds by appositional layering of individual lamellae; however, the mechanism for the longitudinal growth remained unstudied. Now we show, that the surface of the Spicules have towards the tip serrated relief structures that are consistent in size and form with the protrusions on the surface of the Spicules. These protrusions fit into the collagen net that surrounds the Spicules. The widths of the individual lamellae do not show a pronounced size tendency. The apical elongation of the spicule proceeds by piling up cone-like structural units formed from silica. As a support of the assumption that in the extracellular space silicatein(-like) molecules exist that associate with the external surface of the respective spicule immunogold electron microscopic analyses were performed. With the primmorph system from Suberites domuncula we show that silicatein(-like) molecules assemble as string- and net-like arrangements around the Spicules. At their tips the silicatein(-like) molecules are initially stacked and at a later stay also organized into net-like structures. Silicatein(-like) molecules have been extracted from the giant basal spicule of Monorhaphis. Applying the SDS-PAGE technique it could be shown that silicatein molecules associate to dimers and trimers. Higher complexes (filaments) are formed from silicatein(-like) molecules, as can be visualized by electron microscopy (SEM). In the presence of ortho-silicate these filaments become covered with 30-60 nm long small rod-like/cuboid particles of silica. From these data we conclude that the apical elongation of the Spicules of Monorhaphis proceeds by piling up cone-like silica structural units, whose synthesis is mediated by silicatein(-like) molecules. (C) 2008 Elsevier Inc. All rights reserved.
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bioorganic inorganic hybrid composition of sponge Spicules matrix of the giant Spicules and of the comitalia of the deep sea hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Werner E G Muller, Xiaohong Wang, Alexandra Boreiko, Wolfgang Tremel, Carsten Eckert, Klaus Kropf, Hiroshi Ushijima, Werner Geurtsen, Muhammad Nawaz Tahir, Ute SchlosmacherAbstract:The giant basal Spicules of the siliceous sponges Monorhaphis chuni and Monorhaphis intermedia (Hexactinellida) represent the largest biosilica structures on earth (up to 3 m long). Here we describe the construction (lamellar organization) of these Spicules and of the comitalia and highlight their organic matrix in order to understand their mechanical properties. The Spicules display three distinct regions built of biosilica: (i) the outer lamellar zone (radius: >300 mu m), (ii) the bulky axial cylinder (radius: <75 mu m), and (iii) the central axial canal (diameter: <2 mu m) with its organic axial filament. The Spicules are loosely covered with a collagen net which is regularly perforated by 7-10 mu m large holes; the net can be silicified. The silica layers forming the lamellar zone are approximate to 5 mu m thick; the central axial cylinder appears to be composed of almost solid silica which becomes porous after etching with hydrofluoric acid (HF). Dissolution of a complete spicule discloses its complex structure with distinct lamellae in the outer zone (lamellar coating) and a more resistant central part (axial barrel). Rapidly after the release of the organic coating from the lamellar zone the protein layers disintegrate to form irregular clumps/aggregates. In contrast, the proteinaceous axial barrel, hidden in the siliceous axial cylinder, is set up by rope-like filaments. Biochemical analysis revealed that the (dominant) molecule of the lamellar coating is a 27-kDa protein which displays catalytic, proteolytic activity. High resolution electron microscopic analysis showed that this protein is arranged within the lamellae and stabilizes these surfaces by palisade-like pillars. The mechanical behavior of the Spicules was analyzed by a 3-point bending assay, coupled with scanning electron microscopy. The load-extension curve of the spicule shows a biphasic breakage/cracking pattern. The outer lamellar zone cracks in several distinct steps showing high resistance in concert with comparably low elasticity, while the axial cylinder breaks with high elasticity and lower stiffness. The complex bioorganic/inorganic hybrid composition and structure of the Monorhaphis Spicules might provide the blueprint for the synthesis of bio-inspired material, with unusual mechanical properties (strength, stiffness) without losing the exceptional properties of optical transmission. (C) 2007 Elsevier Inc. All rights reserved.
Heinz C Schroder - One of the best experts on this subject based on the ideXlab platform.
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silicateins silicatein interactors and cellular interplay in sponge skeletogenesis formation of glass fiber like Spicules
FEBS Journal, 2012Co-Authors: Xiaohong Wang, Ute Schlosmacher, Heinz C Schroder, Matthias Wiens, Renato Batel, Werner E G MullerAbstract:Biomineralization processes are characterized by controlled deposition of inorganic polymers/minerals mediated by functional groups linked to organic templates. One metazoan taxon, the siliceous sponges, has utilized these principles and even gained the ability to form these polymers/minerals by an enzymatic mechanism using silicateins. Silicateins are the dominant protein species present in the axial canal of the skeletal elements of the siliceous sponges, the Spicules, where they form the axial filament. Silicateins also represent a major part of the organic components of the silica lamellae, which are cylindrically arranged around the axial canal. With the demosponge Suberites domuncula as a model, quantitative enzymatic studies revealed that both the native and the recombinant enzyme display in vitro the same biosilica-forming activity as the enzyme involved in spicule formation in vivo. Monomeric silicatein molecules assemble into filaments via fractal intermediates, which are stabilized by the silicatein-interacting protein silintaphin-1. Besides the silicateins, a silica-degrading enzyme silicase acting as a catabolic enzyme has been identified. Growth of Spicules proceeds in vivo in two directions: first, by axial growth, a process that is controlled by evagination of cell protrusions and mediated by the axial filament-associated silicateins; and second, by appositional growth, which is driven by the extraspicular silicateins, a process that provides the Spicules with their final size and morphology. This radial layer-by-layer accretion is directed by organic cylinders that are formed around the growing spicule and consist of galectin and silicatein. The cellular interplay that controls the morphogenetic processes during spiculogenesis is outlined.
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bio sintering processes in hexactinellid sponges fusion of bio silica in giant basal Spicules from monorhaphis chuni
Journal of Structural Biology, 2009Co-Authors: Werner E G Muller, Zaklina Burghard, Joachim Bill, Xiaohong Wang, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, Matthias WiensAbstract:Abstract The two sponge classes, Hexactinellida and Demospongiae, comprise a skeleton that is composed of siliceous skeletal elements (Spicules). Spicule growth proceeds by appositional layering of lamellae that consist of silica nanoparticles, which are synthesized via the sponge-specific enzyme silicatein. While in demosponges during maturation the lamellae consolidate to a solid rod, the lamellar organization of hexactinellid Spicules largely persists. However, the innermost lamellae, near the spicule core, can also fuse to a solid axial cylinder. Similar to the fusion of siliceous nanoparticles and lamella, in several hexactinellid species individual Spicules unify during sintering-like processes. Here, we study the different stages of a process that we termed bio-sintering, within the giant basal spicule (GBS) of Monorhaphis chuni. During this study, a major GBS protein component (27 kDa) was isolated and analyzed by MALDI-TOF-MS. The sequences were used to isolate and clone the encoding cDNA via degenerate primer PCR. Bioinformatic analyses revealed a significant sequence homology to silicatein. In addition, the native GBS protein was able to mediate bio-silica synthesis in vitro. We conclude that the syntheses of bio-silica in M. chuni, and the subsequent fusion of nanoparticles to lamellae, and finally to Spicules, are enzymatically-driven by a silicatein-like protein. In addition, evidence is now presented that in hexactinellids those fusions involve sintering-like processes.
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axial growth of hexactinellid Spicules formation of cone like structural units in the giant basal Spicules of the hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Xiaohong Wang, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, David Brandt, Jinhe Li, Jaap A Kaandorp, Hermann Gotz, H Duschner, Werner E G MullerAbstract:The glass sponge Monorhaphis chuni (Porifera: Hexactinellida) forms the largest bio-silica structures on Earth; their giant basal Spicules reach sizes of up to 3 m and diameters of 8.5 mm. Previously, it had been shown that the thickness growth proceeds by appositional layering of individual lamellae; however, the mechanism for the longitudinal growth remained unstudied. Now we show, that the surface of the Spicules have towards the tip serrated relief structures that are consistent in size and form with the protrusions on the surface of the Spicules. These protrusions fit into the collagen net that surrounds the Spicules. The widths of the individual lamellae do not show a pronounced size tendency. The apical elongation of the spicule proceeds by piling up cone-like structural units formed from silica. As a support of the assumption that in the extracellular space silicatein(-like) molecules exist that associate with the external surface of the respective spicule immunogold electron microscopic analyses were performed. With the primmorph system from Suberites domuncula we show that silicatein(-like) molecules assemble as string- and net-like arrangements around the Spicules. At their tips the silicatein(-like) molecules are initially stacked and at a later stay also organized into net-like structures. Silicatein(-like) molecules have been extracted from the giant basal spicule of Monorhaphis. Applying the SDS-PAGE technique it could be shown that silicatein molecules associate to dimers and trimers. Higher complexes (filaments) are formed from silicatein(-like) molecules, as can be visualized by electron microscopy (SEM). In the presence of ortho-silicate these filaments become covered with 30-60 nm long small rod-like/cuboid particles of silica. From these data we conclude that the apical elongation of the Spicules of Monorhaphis proceeds by piling up cone-like silica structural units, whose synthesis is mediated by silicatein(-like) molecules. (C) 2008 Elsevier Inc. All rights reserved.
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analysis of the axial filament in Spicules of the demosponge geodia cydonium different silicatein composition in microscleres asters and megascleres oxeas and triaenes
European Journal of Cell Biology, 2007Co-Authors: Werner E G Muller, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Wolfgang Tremel, Carsten Eckert, Stephan E Wolf, Hiroshi Ushijima, Isabel M Muller, Heinz C SchroderAbstract:Abstract The skeleton of the siliceous sponges (Porifera: Hexactinellida and Demospongiae) is supported by Spicules composed of bio-silica. In the axial canals of megascleres, harboring the axial filaments, three isoforms of the enzyme silicatein (- α , - β and - γ ) have been identified until now, using the demosponges Tethya aurantium and Suberites domuncula . Here we describe the composition of the proteinaceous components of the axial filament from small Spicules, the microscleres, in the demosponge Geodia cydonium that possesses megascleres and microscleres. The morphology of the different spicule types is described. Also in G. cydonium the synthesis of the Spicules starts intracellularly and they are subsequently extruded to the extracellular space. In contrast to the composition of the silicateins in the megascleres (isoforms: - α , - β and - γ ), the axial filaments of the microscleres contain only one form of silicatein, termed silicatein- α / β , with a size of 25 kDa. Silicatein- α / β undergoes three phosphorylation steps. The gene encoding silicatein- α / β was identified and found to comprise the same characteristic sites, described previously for silicateins- α or - β . It is hypothesized, that the different composition of the axial filaments, with respect to silicateins, contributes to the morphology of the different types of Spicules.
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formation of giant Spicules in the deep sea hexactinellid monorhaphis chuni schulze 1904 electron microscopic and biochemical studies
Cell and Tissue Research, 2007Co-Authors: Werner E G Muller, Xiaohong Wang, Ute Schlosmacher, Wolfgang Tremel, Carsten Eckert, Klaus Kropf, Christopf Seckert, Stephan E Wolf, Heinz C SchroderAbstract:The siliceous sponge Monorhaphis chuni (Hexactinellida) synthesizes the largest biosilica structures on earth (3 m). Scanning electron microscopy has shown that these Spicules are regularly composed of concentrically arranged lamellae (width: 3–10 μm). Between 400 and 600 lamellae have been counted in one giant basal spicule. An axial canal (diameter: ~2 μm) is located in the center of the Spicules; it harbors the axial filament and is surrounded by an axial cylinder (100–150 μm) of electron-dense homogeneous silica. During dissolution of the Spicules with hydrofluoric acid, the axial filament is first released followed by the release of a proteinaceous tubule. Two major proteins (150 kDa and 35 kDa) have been visualized, together with a 24-kDa protein that cross-reacts with antibodies against silicatein. The Spicules are surrounded by a collagen net, and the existence of a hexactinellidan collagen gene has been demonstrated by cloning it from Aphrocallistes vastus. During the axial growth of the Spicules, silicatein or the silicatein-related protein is proposed to become associated with the surface of the Spicules and to be finally internalized through the apical opening to associate with the axial filament. Based on the data gathered here, we suggest that, in the Hexactinellida, the growth of the Spicules is mediated by silicatein or by a silicatein-related protein, with the orientation of biosilica deposition being controlled by lectin and collagen.
Ute Schlosmacher - One of the best experts on this subject based on the ideXlab platform.
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silicateins silicatein interactors and cellular interplay in sponge skeletogenesis formation of glass fiber like Spicules
FEBS Journal, 2012Co-Authors: Xiaohong Wang, Ute Schlosmacher, Heinz C Schroder, Matthias Wiens, Renato Batel, Werner E G MullerAbstract:Biomineralization processes are characterized by controlled deposition of inorganic polymers/minerals mediated by functional groups linked to organic templates. One metazoan taxon, the siliceous sponges, has utilized these principles and even gained the ability to form these polymers/minerals by an enzymatic mechanism using silicateins. Silicateins are the dominant protein species present in the axial canal of the skeletal elements of the siliceous sponges, the Spicules, where they form the axial filament. Silicateins also represent a major part of the organic components of the silica lamellae, which are cylindrically arranged around the axial canal. With the demosponge Suberites domuncula as a model, quantitative enzymatic studies revealed that both the native and the recombinant enzyme display in vitro the same biosilica-forming activity as the enzyme involved in spicule formation in vivo. Monomeric silicatein molecules assemble into filaments via fractal intermediates, which are stabilized by the silicatein-interacting protein silintaphin-1. Besides the silicateins, a silica-degrading enzyme silicase acting as a catabolic enzyme has been identified. Growth of Spicules proceeds in vivo in two directions: first, by axial growth, a process that is controlled by evagination of cell protrusions and mediated by the axial filament-associated silicateins; and second, by appositional growth, which is driven by the extraspicular silicateins, a process that provides the Spicules with their final size and morphology. This radial layer-by-layer accretion is directed by organic cylinders that are formed around the growing spicule and consist of galectin and silicatein. The cellular interplay that controls the morphogenetic processes during spiculogenesis is outlined.
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bio sintering processes in hexactinellid sponges fusion of bio silica in giant basal Spicules from monorhaphis chuni
Journal of Structural Biology, 2009Co-Authors: Werner E G Muller, Zaklina Burghard, Joachim Bill, Xiaohong Wang, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, Matthias WiensAbstract:Abstract The two sponge classes, Hexactinellida and Demospongiae, comprise a skeleton that is composed of siliceous skeletal elements (Spicules). Spicule growth proceeds by appositional layering of lamellae that consist of silica nanoparticles, which are synthesized via the sponge-specific enzyme silicatein. While in demosponges during maturation the lamellae consolidate to a solid rod, the lamellar organization of hexactinellid Spicules largely persists. However, the innermost lamellae, near the spicule core, can also fuse to a solid axial cylinder. Similar to the fusion of siliceous nanoparticles and lamella, in several hexactinellid species individual Spicules unify during sintering-like processes. Here, we study the different stages of a process that we termed bio-sintering, within the giant basal spicule (GBS) of Monorhaphis chuni. During this study, a major GBS protein component (27 kDa) was isolated and analyzed by MALDI-TOF-MS. The sequences were used to isolate and clone the encoding cDNA via degenerate primer PCR. Bioinformatic analyses revealed a significant sequence homology to silicatein. In addition, the native GBS protein was able to mediate bio-silica synthesis in vitro. We conclude that the syntheses of bio-silica in M. chuni, and the subsequent fusion of nanoparticles to lamellae, and finally to Spicules, are enzymatically-driven by a silicatein-like protein. In addition, evidence is now presented that in hexactinellids those fusions involve sintering-like processes.
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axial growth of hexactinellid Spicules formation of cone like structural units in the giant basal Spicules of the hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Xiaohong Wang, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, David Brandt, Jinhe Li, Jaap A Kaandorp, Hermann Gotz, H Duschner, Werner E G MullerAbstract:The glass sponge Monorhaphis chuni (Porifera: Hexactinellida) forms the largest bio-silica structures on Earth; their giant basal Spicules reach sizes of up to 3 m and diameters of 8.5 mm. Previously, it had been shown that the thickness growth proceeds by appositional layering of individual lamellae; however, the mechanism for the longitudinal growth remained unstudied. Now we show, that the surface of the Spicules have towards the tip serrated relief structures that are consistent in size and form with the protrusions on the surface of the Spicules. These protrusions fit into the collagen net that surrounds the Spicules. The widths of the individual lamellae do not show a pronounced size tendency. The apical elongation of the spicule proceeds by piling up cone-like structural units formed from silica. As a support of the assumption that in the extracellular space silicatein(-like) molecules exist that associate with the external surface of the respective spicule immunogold electron microscopic analyses were performed. With the primmorph system from Suberites domuncula we show that silicatein(-like) molecules assemble as string- and net-like arrangements around the Spicules. At their tips the silicatein(-like) molecules are initially stacked and at a later stay also organized into net-like structures. Silicatein(-like) molecules have been extracted from the giant basal spicule of Monorhaphis. Applying the SDS-PAGE technique it could be shown that silicatein molecules associate to dimers and trimers. Higher complexes (filaments) are formed from silicatein(-like) molecules, as can be visualized by electron microscopy (SEM). In the presence of ortho-silicate these filaments become covered with 30-60 nm long small rod-like/cuboid particles of silica. From these data we conclude that the apical elongation of the Spicules of Monorhaphis proceeds by piling up cone-like silica structural units, whose synthesis is mediated by silicatein(-like) molecules. (C) 2008 Elsevier Inc. All rights reserved.
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bioorganic inorganic hybrid composition of sponge Spicules matrix of the giant Spicules and of the comitalia of the deep sea hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Werner E G Muller, Xiaohong Wang, Alexandra Boreiko, Wolfgang Tremel, Carsten Eckert, Klaus Kropf, Hiroshi Ushijima, Werner Geurtsen, Muhammad Nawaz Tahir, Ute SchlosmacherAbstract:The giant basal Spicules of the siliceous sponges Monorhaphis chuni and Monorhaphis intermedia (Hexactinellida) represent the largest biosilica structures on earth (up to 3 m long). Here we describe the construction (lamellar organization) of these Spicules and of the comitalia and highlight their organic matrix in order to understand their mechanical properties. The Spicules display three distinct regions built of biosilica: (i) the outer lamellar zone (radius: >300 mu m), (ii) the bulky axial cylinder (radius: <75 mu m), and (iii) the central axial canal (diameter: <2 mu m) with its organic axial filament. The Spicules are loosely covered with a collagen net which is regularly perforated by 7-10 mu m large holes; the net can be silicified. The silica layers forming the lamellar zone are approximate to 5 mu m thick; the central axial cylinder appears to be composed of almost solid silica which becomes porous after etching with hydrofluoric acid (HF). Dissolution of a complete spicule discloses its complex structure with distinct lamellae in the outer zone (lamellar coating) and a more resistant central part (axial barrel). Rapidly after the release of the organic coating from the lamellar zone the protein layers disintegrate to form irregular clumps/aggregates. In contrast, the proteinaceous axial barrel, hidden in the siliceous axial cylinder, is set up by rope-like filaments. Biochemical analysis revealed that the (dominant) molecule of the lamellar coating is a 27-kDa protein which displays catalytic, proteolytic activity. High resolution electron microscopic analysis showed that this protein is arranged within the lamellae and stabilizes these surfaces by palisade-like pillars. The mechanical behavior of the Spicules was analyzed by a 3-point bending assay, coupled with scanning electron microscopy. The load-extension curve of the spicule shows a biphasic breakage/cracking pattern. The outer lamellar zone cracks in several distinct steps showing high resistance in concert with comparably low elasticity, while the axial cylinder breaks with high elasticity and lower stiffness. The complex bioorganic/inorganic hybrid composition and structure of the Monorhaphis Spicules might provide the blueprint for the synthesis of bio-inspired material, with unusual mechanical properties (strength, stiffness) without losing the exceptional properties of optical transmission. (C) 2007 Elsevier Inc. All rights reserved.
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analysis of the axial filament in Spicules of the demosponge geodia cydonium different silicatein composition in microscleres asters and megascleres oxeas and triaenes
European Journal of Cell Biology, 2007Co-Authors: Werner E G Muller, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Wolfgang Tremel, Carsten Eckert, Stephan E Wolf, Hiroshi Ushijima, Isabel M Muller, Heinz C SchroderAbstract:Abstract The skeleton of the siliceous sponges (Porifera: Hexactinellida and Demospongiae) is supported by Spicules composed of bio-silica. In the axial canals of megascleres, harboring the axial filaments, three isoforms of the enzyme silicatein (- α , - β and - γ ) have been identified until now, using the demosponges Tethya aurantium and Suberites domuncula . Here we describe the composition of the proteinaceous components of the axial filament from small Spicules, the microscleres, in the demosponge Geodia cydonium that possesses megascleres and microscleres. The morphology of the different spicule types is described. Also in G. cydonium the synthesis of the Spicules starts intracellularly and they are subsequently extruded to the extracellular space. In contrast to the composition of the silicateins in the megascleres (isoforms: - α , - β and - γ ), the axial filaments of the microscleres contain only one form of silicatein, termed silicatein- α / β , with a size of 25 kDa. Silicatein- α / β undergoes three phosphorylation steps. The gene encoding silicatein- α / β was identified and found to comprise the same characteristic sites, described previously for silicateins- α or - β . It is hypothesized, that the different composition of the axial filaments, with respect to silicateins, contributes to the morphology of the different types of Spicules.
Wolfgang Tremel - One of the best experts on this subject based on the ideXlab platform.
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siliceous Spicules enhance fracture resistance and stiffness of pre colonial amazonian ceramics
Scientific Reports, 2015Co-Authors: Filipe Natalio, Tomas P Corrales, Michael Kappl, Hansjurgen Butt, Stephanie Wanka, Paul Zaslansky, Helena Pinto Lima, Wolfgang TremelAbstract:Pottery was a traditional art and technology form in pre-colonial Amazonian civilizations, widely used for cultural expression objects, utensils and as cooking vessels. Abundance and workability of clay made it an excellent choice. However, inferior mechanical properties constrained their functionality and durability. The inclusion of reinforcement particles is a possible route to improve its resistance to mechanical and thermal damage. The Amazonian civilizations incorporated freshwater tree sponge Spicules (cauixi) into the clay presumably to prevent shrinkage and crack propagation during drying, firing and cooking. Here we show that isolated siliceous Spicules are almost defect-free glass fibres with exceptional mechanical stability. After firing, the spicule Young’s modulus increases (from 28 ± 5 GPa to 46 ± 8 GPa) inferring a toughness increment. Laboratory-fabricated ceramic models containing different inclusions (sand, glass-fibres, sponge Spicules) show that mutually-oriented siliceous spicule inclusions prevent shrinkage and crack propagation leading to high stiffness clays (E = 836 ± 3 MPa). Pre-colonial amazonian potters were the first civilization known to employ biological materials to generate composite materials with enhanced fracture resistance and high stiffness in the history of mankind.
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flexible minerals self assembled calcite Spicules with extreme bending strength
Science, 2013Co-Authors: Werner E G Muller, Filipe Natalio, Tomas P Corrales, Martin Panthofer, Dieter Schollmeyer, Ingo Lieberwirth, Michael Kappl, Hansjurgen Butt, Wolfgang TremelAbstract:Silicatein-α is responsible for the biomineralization of silicates in sponges. We used silicatein-α to guide the self-assembly of calcite "Spicules" similar to the Spicules of the calcareous sponge Sycon sp. The self-assembled Spicules, 10 to 300 micrometers (μm) in length and 5 to 10 μm in diameter, are composed of aligned calcite nanocrystals. The Spicules are initially amorphous but transform into calcite within months, exhibiting unusual growth along [100]. They scatter x-rays like twinned calcite crystals. Whereas natural Spicules evidence brittle failure, the synthetic Spicules show an elastic response, which greatly enhances bending strength. This remarkable feature is linked to a high protein content. With nano-thermogravimetric analysis, we measured the organic content of a single spicule to be 10 to 16%. In addition, the Spicules exhibit waveguiding properties even when they are bent.
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bioorganic inorganic hybrid composition of sponge Spicules matrix of the giant Spicules and of the comitalia of the deep sea hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Werner E G Muller, Xiaohong Wang, Alexandra Boreiko, Wolfgang Tremel, Carsten Eckert, Klaus Kropf, Hiroshi Ushijima, Werner Geurtsen, Muhammad Nawaz Tahir, Ute SchlosmacherAbstract:The giant basal Spicules of the siliceous sponges Monorhaphis chuni and Monorhaphis intermedia (Hexactinellida) represent the largest biosilica structures on earth (up to 3 m long). Here we describe the construction (lamellar organization) of these Spicules and of the comitalia and highlight their organic matrix in order to understand their mechanical properties. The Spicules display three distinct regions built of biosilica: (i) the outer lamellar zone (radius: >300 mu m), (ii) the bulky axial cylinder (radius: <75 mu m), and (iii) the central axial canal (diameter: <2 mu m) with its organic axial filament. The Spicules are loosely covered with a collagen net which is regularly perforated by 7-10 mu m large holes; the net can be silicified. The silica layers forming the lamellar zone are approximate to 5 mu m thick; the central axial cylinder appears to be composed of almost solid silica which becomes porous after etching with hydrofluoric acid (HF). Dissolution of a complete spicule discloses its complex structure with distinct lamellae in the outer zone (lamellar coating) and a more resistant central part (axial barrel). Rapidly after the release of the organic coating from the lamellar zone the protein layers disintegrate to form irregular clumps/aggregates. In contrast, the proteinaceous axial barrel, hidden in the siliceous axial cylinder, is set up by rope-like filaments. Biochemical analysis revealed that the (dominant) molecule of the lamellar coating is a 27-kDa protein which displays catalytic, proteolytic activity. High resolution electron microscopic analysis showed that this protein is arranged within the lamellae and stabilizes these surfaces by palisade-like pillars. The mechanical behavior of the Spicules was analyzed by a 3-point bending assay, coupled with scanning electron microscopy. The load-extension curve of the spicule shows a biphasic breakage/cracking pattern. The outer lamellar zone cracks in several distinct steps showing high resistance in concert with comparably low elasticity, while the axial cylinder breaks with high elasticity and lower stiffness. The complex bioorganic/inorganic hybrid composition and structure of the Monorhaphis Spicules might provide the blueprint for the synthesis of bio-inspired material, with unusual mechanical properties (strength, stiffness) without losing the exceptional properties of optical transmission. (C) 2007 Elsevier Inc. All rights reserved.
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analysis of the axial filament in Spicules of the demosponge geodia cydonium different silicatein composition in microscleres asters and megascleres oxeas and triaenes
European Journal of Cell Biology, 2007Co-Authors: Werner E G Muller, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Wolfgang Tremel, Carsten Eckert, Stephan E Wolf, Hiroshi Ushijima, Isabel M Muller, Heinz C SchroderAbstract:Abstract The skeleton of the siliceous sponges (Porifera: Hexactinellida and Demospongiae) is supported by Spicules composed of bio-silica. In the axial canals of megascleres, harboring the axial filaments, three isoforms of the enzyme silicatein (- α , - β and - γ ) have been identified until now, using the demosponges Tethya aurantium and Suberites domuncula . Here we describe the composition of the proteinaceous components of the axial filament from small Spicules, the microscleres, in the demosponge Geodia cydonium that possesses megascleres and microscleres. The morphology of the different spicule types is described. Also in G. cydonium the synthesis of the Spicules starts intracellularly and they are subsequently extruded to the extracellular space. In contrast to the composition of the silicateins in the megascleres (isoforms: - α , - β and - γ ), the axial filaments of the microscleres contain only one form of silicatein, termed silicatein- α / β , with a size of 25 kDa. Silicatein- α / β undergoes three phosphorylation steps. The gene encoding silicatein- α / β was identified and found to comprise the same characteristic sites, described previously for silicateins- α or - β . It is hypothesized, that the different composition of the axial filaments, with respect to silicateins, contributes to the morphology of the different types of Spicules.
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formation of giant Spicules in the deep sea hexactinellid monorhaphis chuni schulze 1904 electron microscopic and biochemical studies
Cell and Tissue Research, 2007Co-Authors: Werner E G Muller, Xiaohong Wang, Ute Schlosmacher, Wolfgang Tremel, Carsten Eckert, Klaus Kropf, Christopf Seckert, Stephan E Wolf, Heinz C SchroderAbstract:The siliceous sponge Monorhaphis chuni (Hexactinellida) synthesizes the largest biosilica structures on earth (3 m). Scanning electron microscopy has shown that these Spicules are regularly composed of concentrically arranged lamellae (width: 3–10 μm). Between 400 and 600 lamellae have been counted in one giant basal spicule. An axial canal (diameter: ~2 μm) is located in the center of the Spicules; it harbors the axial filament and is surrounded by an axial cylinder (100–150 μm) of electron-dense homogeneous silica. During dissolution of the Spicules with hydrofluoric acid, the axial filament is first released followed by the release of a proteinaceous tubule. Two major proteins (150 kDa and 35 kDa) have been visualized, together with a 24-kDa protein that cross-reacts with antibodies against silicatein. The Spicules are surrounded by a collagen net, and the existence of a hexactinellidan collagen gene has been demonstrated by cloning it from Aphrocallistes vastus. During the axial growth of the Spicules, silicatein or the silicatein-related protein is proposed to become associated with the surface of the Spicules and to be finally internalized through the apical opening to associate with the axial filament. Based on the data gathered here, we suggest that, in the Hexactinellida, the growth of the Spicules is mediated by silicatein or by a silicatein-related protein, with the orientation of biosilica deposition being controlled by lectin and collagen.
Alexandra Boreiko - One of the best experts on this subject based on the ideXlab platform.
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bio sintering processes in hexactinellid sponges fusion of bio silica in giant basal Spicules from monorhaphis chuni
Journal of Structural Biology, 2009Co-Authors: Werner E G Muller, Zaklina Burghard, Joachim Bill, Xiaohong Wang, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, Matthias WiensAbstract:Abstract The two sponge classes, Hexactinellida and Demospongiae, comprise a skeleton that is composed of siliceous skeletal elements (Spicules). Spicule growth proceeds by appositional layering of lamellae that consist of silica nanoparticles, which are synthesized via the sponge-specific enzyme silicatein. While in demosponges during maturation the lamellae consolidate to a solid rod, the lamellar organization of hexactinellid Spicules largely persists. However, the innermost lamellae, near the spicule core, can also fuse to a solid axial cylinder. Similar to the fusion of siliceous nanoparticles and lamella, in several hexactinellid species individual Spicules unify during sintering-like processes. Here, we study the different stages of a process that we termed bio-sintering, within the giant basal spicule (GBS) of Monorhaphis chuni. During this study, a major GBS protein component (27 kDa) was isolated and analyzed by MALDI-TOF-MS. The sequences were used to isolate and clone the encoding cDNA via degenerate primer PCR. Bioinformatic analyses revealed a significant sequence homology to silicatein. In addition, the native GBS protein was able to mediate bio-silica synthesis in vitro. We conclude that the syntheses of bio-silica in M. chuni, and the subsequent fusion of nanoparticles to lamellae, and finally to Spicules, are enzymatically-driven by a silicatein-like protein. In addition, evidence is now presented that in hexactinellids those fusions involve sintering-like processes.
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axial growth of hexactinellid Spicules formation of cone like structural units in the giant basal Spicules of the hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Xiaohong Wang, Alexandra Boreiko, Ute Schlosmacher, Heinz C Schroder, David Brandt, Jinhe Li, Jaap A Kaandorp, Hermann Gotz, H Duschner, Werner E G MullerAbstract:The glass sponge Monorhaphis chuni (Porifera: Hexactinellida) forms the largest bio-silica structures on Earth; their giant basal Spicules reach sizes of up to 3 m and diameters of 8.5 mm. Previously, it had been shown that the thickness growth proceeds by appositional layering of individual lamellae; however, the mechanism for the longitudinal growth remained unstudied. Now we show, that the surface of the Spicules have towards the tip serrated relief structures that are consistent in size and form with the protrusions on the surface of the Spicules. These protrusions fit into the collagen net that surrounds the Spicules. The widths of the individual lamellae do not show a pronounced size tendency. The apical elongation of the spicule proceeds by piling up cone-like structural units formed from silica. As a support of the assumption that in the extracellular space silicatein(-like) molecules exist that associate with the external surface of the respective spicule immunogold electron microscopic analyses were performed. With the primmorph system from Suberites domuncula we show that silicatein(-like) molecules assemble as string- and net-like arrangements around the Spicules. At their tips the silicatein(-like) molecules are initially stacked and at a later stay also organized into net-like structures. Silicatein(-like) molecules have been extracted from the giant basal spicule of Monorhaphis. Applying the SDS-PAGE technique it could be shown that silicatein molecules associate to dimers and trimers. Higher complexes (filaments) are formed from silicatein(-like) molecules, as can be visualized by electron microscopy (SEM). In the presence of ortho-silicate these filaments become covered with 30-60 nm long small rod-like/cuboid particles of silica. From these data we conclude that the apical elongation of the Spicules of Monorhaphis proceeds by piling up cone-like silica structural units, whose synthesis is mediated by silicatein(-like) molecules. (C) 2008 Elsevier Inc. All rights reserved.
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bioorganic inorganic hybrid composition of sponge Spicules matrix of the giant Spicules and of the comitalia of the deep sea hexactinellid monorhaphis
Journal of Structural Biology, 2008Co-Authors: Werner E G Muller, Xiaohong Wang, Alexandra Boreiko, Wolfgang Tremel, Carsten Eckert, Klaus Kropf, Hiroshi Ushijima, Werner Geurtsen, Muhammad Nawaz Tahir, Ute SchlosmacherAbstract:The giant basal Spicules of the siliceous sponges Monorhaphis chuni and Monorhaphis intermedia (Hexactinellida) represent the largest biosilica structures on earth (up to 3 m long). Here we describe the construction (lamellar organization) of these Spicules and of the comitalia and highlight their organic matrix in order to understand their mechanical properties. The Spicules display three distinct regions built of biosilica: (i) the outer lamellar zone (radius: >300 mu m), (ii) the bulky axial cylinder (radius: <75 mu m), and (iii) the central axial canal (diameter: <2 mu m) with its organic axial filament. The Spicules are loosely covered with a collagen net which is regularly perforated by 7-10 mu m large holes; the net can be silicified. The silica layers forming the lamellar zone are approximate to 5 mu m thick; the central axial cylinder appears to be composed of almost solid silica which becomes porous after etching with hydrofluoric acid (HF). Dissolution of a complete spicule discloses its complex structure with distinct lamellae in the outer zone (lamellar coating) and a more resistant central part (axial barrel). Rapidly after the release of the organic coating from the lamellar zone the protein layers disintegrate to form irregular clumps/aggregates. In contrast, the proteinaceous axial barrel, hidden in the siliceous axial cylinder, is set up by rope-like filaments. Biochemical analysis revealed that the (dominant) molecule of the lamellar coating is a 27-kDa protein which displays catalytic, proteolytic activity. High resolution electron microscopic analysis showed that this protein is arranged within the lamellae and stabilizes these surfaces by palisade-like pillars. The mechanical behavior of the Spicules was analyzed by a 3-point bending assay, coupled with scanning electron microscopy. The load-extension curve of the spicule shows a biphasic breakage/cracking pattern. The outer lamellar zone cracks in several distinct steps showing high resistance in concert with comparably low elasticity, while the axial cylinder breaks with high elasticity and lower stiffness. The complex bioorganic/inorganic hybrid composition and structure of the Monorhaphis Spicules might provide the blueprint for the synthesis of bio-inspired material, with unusual mechanical properties (strength, stiffness) without losing the exceptional properties of optical transmission. (C) 2007 Elsevier Inc. All rights reserved.
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analysis of the axial filament in Spicules of the demosponge geodia cydonium different silicatein composition in microscleres asters and megascleres oxeas and triaenes
European Journal of Cell Biology, 2007Co-Authors: Werner E G Muller, Anatoli Krasko, Alexandra Boreiko, Ute Schlosmacher, Wolfgang Tremel, Carsten Eckert, Stephan E Wolf, Hiroshi Ushijima, Isabel M Muller, Heinz C SchroderAbstract:Abstract The skeleton of the siliceous sponges (Porifera: Hexactinellida and Demospongiae) is supported by Spicules composed of bio-silica. In the axial canals of megascleres, harboring the axial filaments, three isoforms of the enzyme silicatein (- α , - β and - γ ) have been identified until now, using the demosponges Tethya aurantium and Suberites domuncula . Here we describe the composition of the proteinaceous components of the axial filament from small Spicules, the microscleres, in the demosponge Geodia cydonium that possesses megascleres and microscleres. The morphology of the different spicule types is described. Also in G. cydonium the synthesis of the Spicules starts intracellularly and they are subsequently extruded to the extracellular space. In contrast to the composition of the silicateins in the megascleres (isoforms: - α , - β and - γ ), the axial filaments of the microscleres contain only one form of silicatein, termed silicatein- α / β , with a size of 25 kDa. Silicatein- α / β undergoes three phosphorylation steps. The gene encoding silicatein- α / β was identified and found to comprise the same characteristic sites, described previously for silicateins- α or - β . It is hypothesized, that the different composition of the axial filaments, with respect to silicateins, contributes to the morphology of the different types of Spicules.
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siliceous Spicules in marine demosponges example suberites domuncula
Micron, 2006Co-Authors: Werner E G Muller, Alexandra Boreiko, Wolfgang Tremel, Sergey I Belikov, Carole C Perry, Winfried W C Gieskes, Heinz C SchroderAbstract:All metazoan animals comprise a body plan of different complexity. Since—especially based on molecular and cell biological data—it is well established that all metazoan phyla, including the Porifera (sponges), evolved from a common ancestor the search for common, basic principles of pattern formation (body plan) in all phyla began. Common to all metazoan body plans is the formation of at least one axis that runs from the apical to the basal region; examples for this type of organization are the Porifera and the Cnidaria (diploblastic animals). It seems conceivable that the basis for the formation of the Bauplan in sponges is the construction of their skeleton by Spicules. In Demospongiae (we use the model species Suberites domuncula) and Hexactinellida, the Spicules consist of silica. The formation of the Spicules as the building blocks of the skeleton, starts with the expression of an enzyme which was termed silicatein. Spicule growth begins intracellularly around an axial filament composed of silicatein. When the first layer of silica is made, the Spicules are extruded from the cells and completed extracellularly to reach their the final form and size. While the first steps of spicule formation within the cells are becoming increasingly clear, it remains to be studied how the extracellularly present silicatein strings are formed. The understanding of especially this morphogenetic process will allow an insight into the construction of the amazingly diverse skeleton of the siliceous sponges; animals which evolved between two periods of glaciations, the Sturtian glaciation (710– 680 MYA) and the Varanger-Marinoan ice ages (605–585 MYA). Sponges are—as living fossils—witnesses of evolutionary trends which remained unique in the metazoan kingdom. q 2005 Elsevier Ltd. All rights reserved.
