The microstructure and composition of two mollusc shells were investigated using a combination of light microscopy, SEM, EPMA, and XANES. The shells of Pinna and Pinctada are composed of calcite prisms separated by organic walls. The prismatic units of Pinna are monocrystalline, and those of Pinctada are polycrystalline with internal organic radial membranes. High-spatial-resolution XANES maps for the different S species across adjacent prisms show that sulfate is the principal component in both the intraprismatic organic matrices and the outer membranes. Additionally, these maps confirm that the inner structures of the prismatic units are different for both genera. In many ways, the prisms of Pinna and Pinctada are different and invalidate the "simple prism" concept.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/s1047-8477(03)00054-6 | DOI Listing |
Mar Pollut Bull
December 2024
Institute of Science and Technology for Energy and Environment, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi 11300, Viet Nam; Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi 11300, Viet Nam. Electronic address:
This study aimed to assess the presence of microplastics in bottom sediment and bivalve species, including Pinna bicolor, Atrina vexillum, Saccostrea sp., and Pinctada margaritifera, living in coral reefs on Vietnam's Southern coastal. The average microplastic abundance were 0.
View Article and Find Full Text PDFActa Biomater
April 2022
Aix-Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France. Electronic address:
Biomineralization integrates complex physical and chemical processes bio-controlled by the living organisms through ionic concentration regulation and organic molecules production. It allows tuning the structural, optical and mechanical properties of hard tissues during ambient-condition crystallisation, motivating a deeper understanding of the underlying processes. By combining state-of-the-art optical and X-ray microscopy methods, we investigated early-mineralized calcareous units from two bivalve species, Pinctada margaritifera and Pinna nobilis, revealing chemical and crystallographic structural insights.
View Article and Find Full Text PDFJ Struct Biol
February 2019
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam 14424, Germany.
Cross-sections of calcitic prismatic layers in mollusk shells, cut perpendicular to growth direction, reveal well-defined polygonal shapes of individual "grains" clearly visible by light and electron microscopy. For several kinds of shells, it was shown that the average number of edges in an individual prism approaches six during the growth process. Taking into account the rhombohedral symmetry of calcite, often presented in hexagonal axes, all this led to the long-standing opinion that calcitic prisms grow along the c-axis of calcite.
View Article and Find Full Text PDFSoft Matter
July 2018
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam 14424, Germany.
Numerous mussel species produce byssal threads - tough proteinaceous fibers, which anchor mussels in aquatic habitats. Byssal threads from Mytilus species, which are comprised of modified collagen proteins - have become a veritable archetype for bio-inspired polymers due to their self-healing properties. However, threads from different species are comparatively much less understood.
View Article and Find Full Text PDFJ Microsc
May 2018
CR2P, Centre de Recherche sur la Paléodiversité et les Paléoenvironnements, UMR 7207, MNHN CNRS, Paris, France.
Mollusc shells are complex organomineral structures, the arrangement and composition depending on the species. Most studies are dedicated to shells composed of an aragonite nacreous and a calcite prismatic layer, so the nacreous prismatic model based on Pinctada and Atrina-Pinna. Here, we studied the micro- and nanostructure, the mineralogy and composition of a nacroprismatic bivalve species: Unio pictorum.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!