Search results for "brachiopods"
showing 4 items of 4 documents
Shell proteome of rhynchonelliform brachiopods.
2015
7 pages; International audience; Brachiopods are a phylum of marine invertebrates that have an external bivalved shell to protect their living tissues. With few exceptions, this biomineralized structure is composed of calcite, mixed together with a minor organic fraction, comprising secreted proteins that become occluded in the shell structure, once formed. This organic matrix is thought to display several functions, in particular, to control mineral deposition and to regulate crystallite shapes. Thus, identifying the primary structure of matrix proteins is a prerequisite for generating bioinspired materials with tailored properties. In this study, we employed a proteomic approach to identi…
LES VARIATIONS DU NIVEAU MARIN SUR LE BASSIN DE PARIS AU BATHONIEN-CALLOVIEN. IMPACTS SUR LES COMMUNAUTÉS BENTHIQUES ET SUR L'ÉVOLUTION DES ORNITHELL…
1992
The study deals with the biological impacts of sea-Ievel changes on evolution of a Jurassic benthic fossil group (Ornithellida, Brachiopoda). The different time and scale at which the shifts in marine environments occur leads to the recognition of three interacting dynamic systems: environmental, communities, populations dynamics. The analysis is thus divided into a three steps hierarchy: sequence stratigraphy, analysis of the diversity of brachiopod assemblages, and analysis of morphological variations within omithellid populations. Sequence stratigraphy of the Dogger marly and carbonate successions in the Paris basin provides accurate correlations of depositional environments from shallow…
Productidinid brachiopods (Strophomenata, Productida), including Martinezchaconia luisae, new genus and new species of Linoproductidae, from the Carb…
2018
We describe three brachiopod species of the Suborder Productidina from the Ixtaltepec Formation, Carboniferous of the north of Oaxaca State, southern Mexico, found in peri-reef deposits. Stegacanthia bowsheri and Undaria sp. are members of the families Sentosiidae and Monticuliferidae respectively and were found in strata of the Visean (Middle Mississippian). Martinezchaconia luisae, new genus and species of the Family Linoproductidae, was recollected in Bashkirian-Moscovian (Lower-Middle Pennsylvanian) strata. The respective ages are inferred from the index species of brachiopods associated with the productidines herein described.
Biochemical characteristics of the soluble organic matrix from the shell of three recent terebratulid brachiopod species.
2008
7 pages; International audience; To build their shells, brachiopods secrete a mixture of proteins and polysaccharides, collectively called the organic matrix. This matrix mediates the calcification process by allowing crystal nucleation followed by elongation and finally by stopping the crystal growth. Ultimately, the matrix controls the different microstructures formed. Brachiopod shells are composites with both organic and inorganic constituents intimately associated. This work represents an attempt to characterize the matrices using two combined approaches: (1) scanning electron microscopy for localization within the shell, (2) analysing extracted matrices at the molecular level to deter…