Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Nacre morphology and chemical composition in Atlantic winged oyster Pteria colymbus (Roding, 1798).

ABSTRACT: The microstructure and nanostructure of nacre in Pteria colymbus were studied with high-resolution field emission scanning electron microscopy (FESEM). The tablets were found to be flat and polyhedral with four to eight sides, and lengths ranging from 0.6 to 3.0 µm. They consisted of nanocrystals 41 nm wide, growing in the same direction. X-ray diffraction showed the crystals to be mineral phase aragonite, which was confirmed by Raman spectroscopy. Fourier transform infrared spectroscopy identified a band at 1,786.95 cm^-1 attributed to carboxylate (carbonyl) groups of the proteins present in the organic matrix as well as bands characteristic of calcium carbonate. X-ray fluorescence showed the nacre to contain 98% calcium carbonate, as well as minor elements (Si, Na, S and Sr) and trace elements (Mg, P, Cu, Al, Fe, Cl, K and Zn).

SUBMITTER: Santana P

PROVIDER: S-EPMC8286703 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Nacre morphology and chemical composition in Atlantic winged oyster Pteria colymbus (Röding, 1798).

Santana Pablo P Aldana Aranda Dalila D

PeerJ 20210715

The microstructure and nanostructure of nacre in Pteria colymbus were studied with high-resolution field emission scanning electron microscopy (FESEM). The tablets were found to be flat and polyhedral with four to eight sides, and lengths ranging from 0.6 to 3.0 µm. They consisted of nanocrystals 41 nm wide, growing in the same direction. X-ray diffraction showed the crystals to be mineral phase aragonite, which was confirmed by Raman spectroscopy. Fourier transform infrared spectroscopy ...[more]

PMID: 34316389

Similar Datasets

Novel matrix proteins of Pteria penguin pearl oyster shell nacre homologous to the jacalin-related β-prism fold lectins.

Project description:Nacreous layers of pearl oyster are one of the major functional biominerals. By participating in organic compound-crystal interactions, they assemble into consecutive mineral lamellae-like photonic crystals. Their biomineralization mechanisms are controlled by macromolecules; however, they are largely unknown. Here, we report two novel lectins termed PPL2A and PPL2B, which were isolated from the mantle and the secreted fluid of Pteria penguin oyster. PPL2A is a hetero-dimer composed of α and γ subunits, and PPL2B is a homo-dimer of β subunit, all of which surprisingly shared sequence homology with the jacalin-related plant lectin. On the basis of knockdown experiments at the larval stage, the identification of PPLs in the shell matrix, and in vitro CaCO3 crystallization analysis, we conclude that two novel jacalin-related lectins participate in the biomineralization of P. penguin nacre as matrix proteins. Furthermore, it was found that trehalose, which is specific recognizing carbohydrates for PPL2A and is abundant in the secreted fluid of P. penguin mantle, functions as a regulatory factor for biomineralization via PPL2A. These observations highlight the unique functions, diversity and molecular evolution of this lectin family involved in the mollusk shell formation.

| S-EPMC4223035 | biostudies-literature

Control of nacre biomineralization by Pif80 in pearl oyster.

Project description:Molluscan nacre is a fascinating biomineral consisting of a highly organized calcium carbonate composite that provides unique fracture toughness and an iridescent color. Organisms elaborately control biomineralization using organic macromolecules. We propose the involvement of the matrix protein Pif80 from the pearl oyster Pinctada fucata in the development of the inorganic phase during nacre biomineralization, based on experiments using the recombinant form of Pif80. Through interactions with calcium ions, Pif80 participates in the formation of polymer-induced liquid precursor-like amorphous calcium carbonate granules and stabilizes these granules by forming calcium ion-induced coacervates. At the calcification site, the disruption of Pif80 coacervates destabilizes the amorphous mineral precursors, resulting in the growth of a crystalline structure. The redissolved Pif80 controls the growth of aragonite on the polysaccharide substrate, which contributes to the formation of polygonal tablet structure of nacre. Our findings provide insight into the use of organic macromolecules by living organisms in biomineralization.

| S-EPMC5540247 | biostudies-other

Sulfated Polysaccharide Isolated from the Nacre of Pearl Oyster Improves Scopolamine-Induced Memory Impairment.

Project description:Pearl and nacre have been used in traditional medicines for treating brain dysfunctions, such as epilepsy, myopia, palpitations and convulsions. We previously showed that a pearl oyster nacre extract improves scopolamine-induced memory impairments using the Y-maze, Banes maze and object recognition tests. In this study, we aimed to isolate the memory-improving substance using ion-exchange column chromatography and reverse-phase column chromatography and elucidate the molecular mechanism underlying its memory-improving activity. The isolated substance was found to be a sulfated polysaccharide with a molecular weight of approximately 750 kDa. Monosaccharide composition analysis showed that it was rich in galactose, glucose, mannose and uronic acid. Furthermore, the mRNA expression levels of oxidative stress, inflammatory response and neuroprotective factors in the cerebral cortex were investigated. Treatment with the polysaccharide increased the expression levels of the antioxidant enzymes Cu, Zn -superoxide dismutase (SOD) and catalase and attenuated the scopolamine-mediated upregulation of the inflammatory cytokines interleukin-1 and interleukin-6. In addition, the polysaccharide suppressed the decrease in the expression levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). These findings strongly suggest that the polysaccharide in the nacre extract mediated its antiamnesic effects by preventing oxidative stress and inflammation and increasing the expression levels of BDNF and NGF.

| S-EPMC8063846 | biostudies-literature

Morphology and Chemical Composition of Magnetic Particles Separated from Coal Fly Ash.

Project description:Iron and other metal compounds are the materials that often appear in coal seams, because they also appear as a component of former organic matter in coal rocks. Although iron is the dominant element in coal rocks, other metals such as titanium, lead, cobalt, nickel, and copper are also present. In this study, the properties of magnetic particles of a size between 1 and 20 µm of globular structure and iron containing, were separated from coal fly ash, and studied using a scanning electron microscopy, energy disperse spectroscopy, and X-ray diffraction spectroscopy. The investigations were comprised of micrographs of the structure of these particles, their elemental composition, and phase analysis.

| S-EPMC8779241 | biostudies-literature

MicroRNA, Pm-miR-2305, Participates in Nacre Formation by Targeting Pearlin in Pearl Oyster Pinctada martensii.

Project description:MicroRNAs (miRNAs) are noncoding RNA molecules that function as negative regulators of target genes. In our previous research, 258 pm-miRNAs were identified in Pinctada martensii by Solexa deep sequencing. Pm-miR-2305 was one of the identified pm-miRNAs with a potential function in biomineralization. In the present study, the precursor of pm-miR-2305 was predicted with 96 bp, containing a characteristic hairpin structure. Stem-loop qRT-PCR analysis indicated that pm-miR-2305 was constitutively expressed in all the tissues (adductor muscle, gill, mantle, hepatopancreas, foot, and gonad) of P. martensii and was highly expressed in the foot. After the over-expression of pm-miR-2305 in the mantle by mimics injection into the muscle of P. martensii, nacre demonstrated disorderly growth, as detected by scanning electron microscopy. Dual luciferase reporter gene assay indicated that pm-miR-2305 mimics could significantly inhibit the luciferase activity of the reporter containing the 3'UTR of the pearlin gene. Western blot analysis demonstrated that the protein expression of pearlin was down-regulated in the mantle tissue after the over-expression of pm-miR-2305. Therefore, our data showed that pm-miR-2305 participated in nacre formation by targeting pearlin in P. martensii.

| S-EPMC4613262 | biostudies-literature

Different secretory repertoires control the biomineralization processes of prism and nacre deposition of the pearl oyster shell.

Project description:Mollusca evolutionary success can be attributed partly to their efficiency to sustain and protect their soft body with an external biomineralized structure, the shell. Current knowledge of the protein set responsible for the formation of the shell microstructural polymorphism and unique properties remains largely patchy. In Pinctada margaritifera and Pinctada maxima, we identified 80 shell matrix proteins, among which 66 are entirely unique. This is the only description of the whole "biomineralization toolkit" of the matrices that, at least in part, is thought to regulate the formation of the prismatic and nacreous shell layers in the pearl oysters. We unambiguously demonstrate that prisms and nacre are assembled from very different protein repertoires. This suggests that these layers do not derive from each other.

| S-EPMC3529032 | biostudies-literature

Wood chemical composition in species of Cactaceae: the relationship between lignification and stem morphology.

Project description:In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs) and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content) in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous) with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35%) of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level.

| S-EPMC4399841 | biostudies-literature

Annual gametogenic phenology of oyster, Magallana bilineata (Roding, 1798) collected from the west coast of Moheshkhali Island, Cox's Bazar, Bangladesh.

Project description:The current study aimed to describe the annual gametogenic phenology of the oyster Magallana bilineata (Röding, 1798) (=Crassostrea madrasensis), which is found on the west coast of Moheshkhali Island, Cox's Bazar, Bangladesh. Samples were drawn monthly from the intertidal region during low tide, from which 20 adult individuals were selected at random for biometry and histology. The mean condition index (CI), a ratio of tissue wet weight (g) to shell length (cm), varied from 0.58 ± 0.08 to 1.32 ± 0.36. Histology revealed two spawning cycles in the habitat of M. bilineata over the 12 months of the study. Gametogenesis initiated in December and May, and ripe animals principally occurred from July to September and February to May. In the habitat, M.bilineata exhibited two spawning peak periods: April to June and August to October. The undifferentiated stage as a preparatory step for the next spawning extended from November to February for the first spawning cycle and for a brief period in June for the next spawning cycle. The initiation of spawning in March could be associated with the high-level decline of salinity and increased temperature between February and March, in association with the annual rainfall start, whereas the next spawning cycle could be associated with a gradual increase in salinity. No spawning activity was reported from December to February, when the water temperature remained below 22 °C. Further study could be undertaken on the timing of spatfall of M.bilineata in the habitat to harvest spats for commercial farming of this promising species.

| S-EPMC11004762 | biostudies-literature

Correction: Wood Chemical Composition in Species of Cactaceae: The Relationship between Lignification and Stem Morphology.

Project description: Not available

| S-EPMC4454700 | biostudies-literature

Chemical epigenetics alters the secondary metabolite composition of guttate excreted by an atlantic-forest-soil-derived Penicillium citreonigrum.

Project description:Chemical epigenetic manipulation of Penicillium citreonigrum led to profound changes in the secondary metabolite profile of its guttate. While guttate from control cultures exhibited a relatively simple assemblage of secondary metabolites, the guttate collected from cultures treated with 50 muM 5-azacytidine (a DNA methyltransferase inhibitor) was highly enriched in compounds representing at least three distinct biosynthetic families. The metabolites obtained from the fungus included six azaphilones (sclerotiorin (1), sclerotioramine (6), ochrephilone (2), dechloroisochromophilone III (3), dechloroisochromophilone IV (4), and 6-((3E,5E)-5,7-dimethyl-2-methylenenona-3,5-dienyl)-2,4-dihydroxy-3-methylbenzaldehyde (5)), pencolide (7), and two new meroterpenes (atlantinones A and B (9 and 10, respectively)). While pencolide was detected in the exudates of both control and 5-azacytidine-treated cultures, all of the other natural products were found exclusively in the guttates of the epigenetically modified fungus. All of the metabolites from the P. citreonigrum guttate were tested for antimicrobial activity in a disk diffusion assay. Both sclerotiorin and sclerotioramine caused modest inhibition of Staphylococcus epidermidis growth; however, only sclerotioramine was active against a panel of Candida strains.

| S-EPMC2878378 | biostudies-literature