Calcium binding by organic matrix of developing bovine enamel

1981 ◽  
Vol 26 (6) ◽  
pp. 483-485 ◽  
Author(s):  
C. Drinkard ◽  
L. Gibson ◽  
M.A. Crenshaw ◽  
J.W. Bawden
Keyword(s):  
Calcium Binding ◽  
Organic Matrix ◽  
Bovine Enamel

Fluoride-binding by the organic matrix of developing bovine enamel

1978 ◽  
Vol 23 (4) ◽  
pp. 285-287 ◽  
Author(s):  
M.A. Crenshaw ◽  
A. Wennberg ◽  
J.W. Bawden
Keyword(s):  
Organic Matrix ◽  
Bovine Enamel

Absence of in-vitro fluoride-binding by the organic matrix of developing bovine enamel

1988 ◽  
Vol 33 (7) ◽  
pp. 531-533 ◽  
Author(s):  
A. Lussi ◽  
R.A. Fridell ◽  
M.A. Crenshaw ◽  
J.W. Bawden
Keyword(s):  
Organic Matrix ◽  
Bovine Enamel

Phosphopeptides of Enamel Matrix

1979 ◽  
Vol 58 (2_suppl) ◽  
pp. 790-809 ◽  
Author(s):  
M.J. Glimcher
Keyword(s):  
Calcium Binding ◽  
Cyanogen Bromide ◽  
Peptide Sequencing ◽  
Partial Sequence ◽  
Enamel Matrix ◽  
Ordered Structures ◽  
Enamel Proteins ◽  
Polypeptide Chains ◽  
Bovine Enamel

Although the tripeptides Glu-O-Phosphoserine-Tyr and Glu-O-Phosphoserine-Leu have been identified in embryonic bovine enamel proteins,1,2 the issue of whether both sequences occur in each of the phosphopeptides, or whether certain sequences occur in specific peptides only, has recently been resolved by isolating homogeneous samples of E33 and E44. All three of the Ser residues of both peptides are phosphorylated. All three in E3 are in the sequence Glu-O-Phosphoserine-Leu, and all three in E4 are in the sequence Glu-O-Phosphoserine-Tyr. It was not possible to sequence either of the polypeptide chains directly by automatic peptide sequencing. However, a partial sequence of E4 was constructed from data derived from peptides isolated after cyanogen bromide, trypsin and chymotrypsin digestions. The presence of Glu, Tyr and Leu adjacent to and near the O-Phosphoserine [Ser(L)] residues and the 2°, 3° and higher ordered structures of the enamel phosphopeptides may be important in calcium binding and mineralization.

The in vitro Uptake of Fluoride by Secretory and Maturation Stage Bovine Enamel

1988 ◽  
Vol 67 (2) ◽  
pp. 487-490 ◽  
Author(s):  
R.A. Fridell ◽  
A. Lussi ◽  
M.A. Crenshaw ◽  
J.W. Bawden
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Organic Matrix ◽  
Maturation Stage ◽  
Fluoride Uptake ◽  
Surface Areas ◽  
Bet Method ◽  
Two Stages ◽  
Bovine Enamel

The objectives of this study were to determine the specific surface area of secretory-stage and of maturation-stage enamel, to compare the fluoride uptake by isolated enamel at these two stages on a surface-area basis, and to examine the effect of the organic matrix on the fluoride uptake by whole enamel. Fetal bovine secretory and maturation stage enamel samples were collected, and a portion of the enamel at each developmental stage was treated with hydrazine for removal of the organic matrix. The specific surface areas of the enamel mineral, as determined by the multi-point BET method, were 59.3 m2/ g in the secretory stage and 37.9 m2/g in the maturation stage. Whole and deproteinated enamel samples were equilibrated in buffered solutions containing 10 -5 to 10-3 mol/L fluoride, and the uptake was measured with a fluoride specific electrode. The results indicate that the in vitro fluoride uptake was controlled solely by the surface area of the apatitic mineral and that the organic matrix did not contribute to the fluoride uptake.

Micro Energy-Dispersive X-Ray Fluoresence Mapping of Enamel and Dental Materials after Chemical Erosion

2012 ◽  
Vol 18 (5) ◽  
pp. 1112-1117 ◽  
Author(s):  
Luís Eduardo Silva Soares ◽  
Rodrigo de Oliveira ◽  
Sídnei Nahórny ◽  
Ana Maria do Espírito Santo ◽  
Airton Abrahão Martin
Keyword(s):  
Soft Drink ◽  
Dental Materials ◽  
Glass Ionomer Cement ◽  
Chemical Properties ◽  
Organic Matrix ◽  
Energy Dispersive ◽  
X Ray ◽  
Surface Sealants ◽  
Bovine Enamel ◽  
Mineral Loss

AbstractEnergy-dispersive X-ray fluorescence was employed to test the hypothesis that beverage consumption or mouthwash utilization will change the chemical properties of dental materials and enamel mineral content. Bovine enamel samples (n = 45) each received two cavity preparations (n = 90), each pair filled with one of three dental materials (R: nanofilled composite resin; GIC: glass-ionomer cement; RMGIC: resin-modified GIC). Furthermore, they were treated with three different solutions (S: saliva; E: erosion/Pepsi Twist®; or EM: erosion+mouthwash/Colgate Plax®). It was found that mineral loss in enamel was greater in GICE samples than in RE > RMGICE > RMGICEM > REM > GICEM. An increased percentage of Zr was found in REM indicating organic matrix degradation. Dental materials tested (R, GIC, and RMGIC) were not able to protect adjacent enamel from acid erosion by the soft drink tested. The use of mouthwash promoted protection of enamel after erosion by the soft drink. To avoid chemical dissolution by mouthwashes, protection by resin composites with surface sealants is recommended.

scholarly journals Evolution of the Avian Eggshell Biomineralization Protein Toolkit – New Insights From Multi-Omics

2021 ◽  
Vol 12 ◽  
Author(s):  
Nathalie Le Roy ◽  
Lilian Stapane ◽  
Joël Gautron ◽  
Maxwell T. Hincke
Keyword(s):  
Calcium Binding ◽  
Egg Quality ◽  
Current Knowledge ◽  
Bird Species ◽  
Mechanical Damage ◽  
Organic Matrix ◽  
Human Consumption ◽  
Terrestrial Environment ◽  
Avian Reproduction ◽  
Evolutionary Context

The avian eggshell is a remarkable biomineral, which is essential for avian reproduction; its properties permit embryonic development in the desiccating terrestrial environment, and moreover, are critically important to preserve unfertilized egg quality for human consumption. This calcium carbonate (CaCO3) bioceramic is made of 95% calcite and 3.5% organic matrix; it protects the egg contents against microbial penetration and mechanical damage, allows gaseous exchange, and provides calcium for development of the embryonic skeleton. In vertebrates, eggshell occurs in the Sauropsida and in a lesser extent in Mammalia taxa; avian eggshell calcification is one of the fastest known CaCO3 biomineralization processes, and results in a material with excellent mechanical properties. Thus, its study has triggered a strong interest from the researcher community. The investigation of eggshell biomineralization in birds over the past decades has led to detailed characterization of its protein and mineral constituents. Recently, our understanding of this process has been significantly improved using high-throughput technologies (i.e., proteomics, transcriptomics, genomics, and bioinformatics). Presently, more or less complete eggshell proteomes are available for nine birds, and therefore, key proteins that comprise the eggshell biomineralization toolkit are beginning to be identified. In this article, we review current knowledge on organic matrix components from calcified eggshell. We use these data to analyze the evolution of selected matrix proteins and underline their role in the biological toolkit required for eggshell calcification in avian species. Amongst the panel of eggshell-associated proteins, key functional domains are present such as calcium-binding, vesicle-binding and protein-binding. These technical advances, combined with progress in mineral ultrastructure analyses, have opened the way for new hypotheses of mineral nucleation and crystal growth in formation of the avian eggshell, including transfer of amorphous CaCO3 in vesicles from uterine cells to the eggshell mineralization site. The enrichment of multi-omics datasets for bird species is critical to understand the evolutionary context for development of CaCO3 biomineralization in metazoans, leading to the acquisition of the robust eggshell in birds (and formerly dinosaurs).

scholarly journals THE STRUCTURE AND ORGANIZATION OF, AND THE RELATIONSHIP BETWEEN THE ORGANIC MATRIX AND THE INORGANIC CRYSTALS OF EMBRYONIC BOVINE ENAMEL

1964 ◽  
Vol 23 (3) ◽  
pp. 447-497 ◽  
Author(s):  
Dorothy F. Travis ◽  
Melvin J. Glimcher
Keyword(s):  
Organic Matrix ◽  
Thin Plates ◽  
Crystal Thickness ◽  
Mineralized Tissue ◽  
Cross Sectional ◽  
Thin Filaments ◽  
Inorganic Crystals ◽  
The Individual ◽  
Oriented Parallel ◽  
Bovine Enamel

Electron microscope and electron diffraction studies of developing embryonic bovine enamel have revealed the organization of the organic matrix and the inorganic crystals. The most recently deposited inorganic crystals located at the ameloblast-enamel junction are thin plates, approximately 1300 A long, 400 A wide, and 19 A thick. During maturation of the enamel, crystal growth occurs primarily by an increase in crystal thickness. Statistical analyses failed to show a significant change in either the width or the length of the crystals during the period of maturation studied. Even in the earliest stages of calcification, the crystals are organized within the prisms so that their long axes (c-axes) are oriented parallel to the long axes of the prisms but randomly distributed about their long axes. With maturation of the enamel, the crystals become more densely packed and more highly oriented within the prisms. The organic matrix in decalcified sections of enamel is strikingly similar in its over-all organization to that of the fully mineralized tissue. When viewed in longitudinal prism profiles, the intraprismatic organic matrix is composed of relatively thin dense lines, approximately 48 A wide, which are relatively parallel to each other and have their fiber axes parallel to the long axes of the prisms within which they are located. Many of these dense lines, which have the appearance of thin filaments, are organized into doublets, the individual 48 A wide filaments of the doublets being separated by approximately 120 A. When observed in oblique prism profiles, the intraprismatic organic matrix is likewise remarkably similar in general orientation and organization to that of the fully mineralized tissue. Moreover, the spaces between adjacent doublets or between single filaments have the appearance of compartments. These compartments, more clearly visualized in cross- or near cross-sectional prism profiles, are oval or near oval in shape. Therefore, the appearance of the intraprismatic organic matrix (in longitudinal, oblique, and cross-sectional prism profiles) indicates that it is organized into tubular sheaths which are oriented with their long axes parallel to the long axes of the prisms in which they are located, but randomly oriented about their own long axes, an orientation again remarkably "blue printing" that of the inorganic crystals. The predominant feature of the walls of the tubular sheaths, when viewed in cross- or near cross-section, is that of continuous sheets, although in many cases closely packed dot-like structures of approximately 48 A were also observed, suggesting that the wall of the sheaths consists of a series of closely packed filaments. The 48 A wide dense lines (filaments) representing the width of the sheath wall were resolved into two dense strands when viewed in longitudinal prism profiles. Each strand was 12 A wide and was separated by a less electron-dense space 17 A wide. The intraprismatic organic matrix is surrounded by a prism sheath which corresponds in mineralized sections to the electron-lucent uncalcified regions separating adjacent prisms. Structurally, the prism sheaths appear to consist of filaments arranged in basket-weave fashion.

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