Search results for "Minerali"
showing 10 items of 374 documents
Hierarchical architecture of sponge spicules: biocatalytic and structure-directing activity of silicatein proteins as model for bioinspired applicati…
2016
Since the first description of the silicateins, a group of enzymes that mediate the formation of the amorphous, hydrated biosilica of the skeleton of the siliceous sponges, much progress has been achieved in the understanding of this biomineralization process. These discoveries include, beside the proof of the enzymatic nature of the sponge biosilica formation, the dual property of the enzyme, to act both as a structure-forming and structure-guiding protein, and the demonstration that the initial product of silicatein is a soft, gel-like material that has to undergo a maturation process during which it achieves its favorable physical-chemical properties allowing the development of various t…
Minerality in wine: Towards the reality behind the myths
2018
Revue non indexée dans JCR. This article belongs to the Special Issue Wine Components and Chemical Mechanisms for Health; Tasting minerality in wine is highly fashionable, but it is unclear what this involves. The present review outlines published work concerning how minerality in wine is perceived and conceptualised by wine professionals and consumers. Studies investigating physico-chemical sources of perceived minerality in wine are reviewed also. Unusually, for a wine sensory descriptor, the term frequently is taken to imply a genesis: the sensation is the taste of minerals in the wine that were transported through the vine from the vineyard rocks and soils. Recent studies exploring tast…
SNPs in bone-related miRNAs are associated with the osteoporotic phenotype
2017
AbstractBiogenesis and function of microRNAs can be influenced by genetic variants in the pri-miRNA sequences leading to phenotypic variability. This study aims to identify single nucleotide polymorphisms (SNPs) affecting the expression levels of bone-related mature microRNAs and thus, triggering an osteoporotic phenotype. An association analysis of SNPs located in pri-miRNA sequences with bone mineral density (BMD) was performed in the OSTEOMED2 cohort (n = 2183). Functional studies were performed for assessing the role of BMD-associated miRNAs in bone cells. Two SNPs, rs6430498 in the miR-3679 and rs12512664 in the miR-4274, were significantly associated with femoral neck BMD. Further, we…
The shell of the invasive bivalve species Dreissena polymorpha: biochemical, elemental and textural Investigations.
2016
28 pages; International audience; The zebra mussel Dreissena polymorpha is a well-established invasive model organism. Although extensively used in environmental sciences, virtually nothing is known of the molecular process of its shell calcification. By describing the microstructure, geochemistry and biochemistry/proteomics of the shell, the present study aims at promoting this species as a model organism in biomineralization studies, in order to establish a bridge with ecotoxicology, while sketching evolutionary conclusions. The shell of D. polymorpha exhibits the classical crossed-lamellar/complex crossed lamellar combination found in several heterodont bivalves, in addition to an extern…
Biomineralization toolkit: the importance of sample cleaning prior to the characterization of biomineral proteomes.
2013
In an interesting work published recently in PNAS, Drake et al. (1) presented a proteomic study of the skeleton from the stony coral Stylophora pistillata . This study identified proteins that are associated to the mineral phase (i.e., that potentially contribute to shape the skeleton). In other words, this set of proteins is supposed to represent the so-called “biomineralization toolkit.” Although some of the 36 proteins reported in Drake et al. (1) appear as genuine extracellular matrix (ECM) proteins related to biomineralization, such as coral acid-rich proteins or carbonic anhydrase, some others are obvious intracellular contaminants that should not be considered as skeletal organic mat…
Comparative evaluation of bioactive cements on biomimetic remineralization of dentin
2020
Background This study was designed to quantitatively compare the presence of apatite peaks on demineralized dentin to induced bio-mimetically by bioactive commercial materials. Material and methods Dentin slice specimens (n=6) were prepared and demineralized by by17% EDTA for 2 hours. Each disks materials (Theracal, Biodentine, CPP-ACP) were freshly prepared and was maintained in close contact with a demineralized dentin specimen immersed in PBS solution during one week. To evaluation of bioactivity, cements disks (n=6) were prepared from each material and immersed in PBS solution for one week. The bioactivity and remineralization ability was evaluated using FTIR spectroscopy and Scanning E…
atzgene expressions during atrazine degradation in the soil drilosphere
2010
One of the various ecosystemic services sustained by soil is pollutant degradation mediated by adapted soil bacteria. The pathways of atrazine biodegradation have been elucidated but in situ expression of the genes involved in atrazine degradation has yet to be demonstrated in soil. Expression of the atzA and atzD genes involved in atrazine dechlorination and s-triazine ring cleavage, respectively, was investigated during in situ degradation of atrazine in the soil drilosphere and bulked samples from two agricultural soils that differed in their ability to mineralize atrazine. Interestingly, expression of the atzA gene, although present in both soils, was not detected. Atrazine mineralizati…
Silicateins, silicatein interactors and cellular interplay in sponge skeletogenesis: formation of glass fiber-like spicules
2012
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 …
2,4-D impact on bacterial communities, and the activity and genetic potential of 2,4-D degrading communities in soil
2006
The key role of telluric microorganisms in pesticide degradation is well recognized but the possible relationships between the biodiversity of soil microbial communities and their functions still remain poorly documented. If microorganisms influence the fate of pesticides, pesticide application may reciprocally affect soil microorganisms. The objective of our work was to estimate the impact of 2,4-D application on the genetic structure of bacterial communities and the 2,4-D-degrading genetic potential in relation to 2,4-D mineralization. Experiments combined isotope measurements with molecular analyses. The impact of 2,4-D on soil bacterial populations was followed with ribosomal intergenic…
Diuron mineralisation in a Mediterranean vineyard soil: impact of moisture content and temperature
2010
BACKGROUND: The diuron-mineralising ability of the microbiota of a Mediterranean vineyard soil exposed each year to this herbicide was measured. The impact of soil moisture and temperature on this microbial activity was assessed. RESULTS: The soil microbiota was shown to mineralise diuron. This mineralising activity was positively correlated with soil moisture content, being negligible at 5% and more than 30% at 20% soil moisture content. According to a double Gaussian model applied to fit the dataset, the optimum temperature/soil moisture conditions were 27.9 °C/19.3% for maximum mineralisation rate and 21.9 °C/18.3% for maximum percentage mineralisation. The impact of temperature and soil…