Molekulare Mechanismen der Biomineralisation bei der Bildung von Kalkschalen

Krampitz, G.; Graser, Gabriele

doi:10.1002/ange.19881000906

Cited by 17 publications

(3 citation statements)

References 78 publications

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“…Compared with membrane-controlled nucleation processes in shells, however (Krampitz & Graser, 1988), bacterially induced calcification processes are strongly dependent on the type and texture of the environment in which they proceed. It is quite evident, therefore, that the heterogeneous and dynamic environment of biolaminated deposits controls size, form and spatial arrangement of carbonate precipitates.…”

Section: Substrate Heterogeneity and Form Variation Of Particlesmentioning

confidence: 99%

Structural diversity of biogenic carbonate particles in microbial mats

et al. 1994

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Non-skeletal carbonate particles in microbial mats were studied using thin sections and scanning electron microscopy. The microbial mats form biolaminated units (so-called potential stromatolites) in salterns. This study emphasizes the coexistence of different particle forms and makes a genetic connection between the heterogeneity of the organic substrate built by bacteria and diatoms and their extracellular polymeric substances (EPS). Whereas allochthonous particles are scarce, Lanzarote microbial mats provide various autochthonous surfaces for the attachment of cells and EPS, including sheaths and capsules of cyanobacteria, frustules of diatoms, metabolic products such as gas bubbles, liquid globules and faecal pellets, as well as the carbonate precipitates themselves. Morphologically different carbonate precipitates are: (i) calcified organic clumps (peloids), (ii) particles composed of concentric aragonite and biofilm laminae (ooids and oncoids), (iii) isolated particles floating in gel-supported mats and coated by rims of fibrous cement (cortoids), (iv) particles bound by cryptocrystalline matrices or cement, resulting in aggregate grains and (v) lobate cement which fills out spaces and pores and fixes the particles. Peloids are suggested to represent faecal pellets although microbial systems also generate cell clumps by non-faecal processes. Ooid and oncoid constructions clearly record alternating processes of biofilm accumulation and aragonite encrustation. Further characteristic features of carbonate particles generated within a microbial mat are: (i) an irregular distribution ranging from isolated particles floating within the gel-like matrix to closely packed particles, (ii) the amalgamation of different particle types (e.g. peloids and ooids) in aggregate grains, (iii) the heterogeneous nature of nuclei comprising bacterial clumps, intraclasts, individual cells, cell colonies and bubbles, (iv) the enrichment of remains, casts and imprints of cells within precipitates and (v) deformation (e.g. truncated cortices) of particles.

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Section: Substrate Heterogeneity and Form Variation Of Particlesmentioning

confidence: 99%

Structural diversity of biogenic carbonate particles in microbial mats

et al. 1994

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“…It is the main constituent of bones and teeth. These two metal ions play an essential role in the activation of enzymes, complexation with nucleic acids, nerve impulse transmission, muscle contraction, and carbohydrate metabolism. − A range of model complexes containing these two metals have been prepared as probes to elucidate the mode of binding of these metals. , The studies have focused on the use of aspartate, glutamate, orontate, or pyroglutamate ligands 13 as careful investigation of the calcium or magnesium binding sites on proteins has shown that the acidic groups of l -aspartic acid and l -gluatmic acid are the key anchoring positions for these ions. − On the other hand, barium and strontium are considered as trace elements in the body. Strontium is rated nontoxic, and traces of it appear to be essential, though the reason for this is not yet known.…”

Section: Introductionmentioning

confidence: 99%

Reactions of 2-Mercaptobenzoic Acid with Divalent Alkaline Earth Metal Ions: Synthesis, Spectral Studies, and Single-Crystal X-ray Structures of Calcium, Strontium, and Barium Complexes of 2,2‘-Dithiobis(benzoic acid)^,

2001

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The treatment of MCl(2).nH(2)O (M = Ca, Sr, or Ba) with 2-mercaptobenzoic acid (H-2-MBA) in a 1:2 ratio in an EtOH/H(2)O/NH(3) mixture leads to the formation of extended polymeric solids [[Ca(OOCC(6)H(4)SSC(6)H(4)COO)(H(2)O)(2)].0.5(C(2)H(5)OH)](n)(1), [[Sr(OOCC(6)H(4)SSC(6)H(4)COO)(H(2)O)(2)].0.5(C(2)H(5)OH)](n)(2), and [[Ba(2)(OOCC(6)H(4)SSC(6)H(4)COO)(2)(H(2)O)(2)].0.5H(2)O](n)(3), respectively. In all of the cases, under the reaction conditions employed, the H-2-MBA ligand undergoes thiol oxidation to form 2,2'-dithiobis(benzoic acid) (H(2)-DTBB). While the DTBB forms a 1:1 complex with heavier alkaline earth metals (1-3), only an ammonium salt, [(HOOCC(6)H(4)SSC(6)H(4)COOH)(HOOCC(6)H(4)SSC(6)H(4)COONH(4))] (4), was obtained as the final product in the reaction of H-2-MBA with MgCl(2).6H(2)O. Compounds 1-4 have been characterized with the aid of elemental analysis, thermal analysis, and infrared spectroscopic studies. All of the products are found to be thermally stable and do not melt on heating to 250 degrees C. Thermogravimetry on complexes 1-3 indicates the loss of coordinated and lattice water/solvent molecules below 200 degrees C (for complex 2) or 350 degrees C (for complexes 1 and 3). The solid-state structures of all of the derivatives 1-4 have been established by single-crystal X-ray diffraction studies. The calcium and strontium coordination polymers 1 and 2 are isomorphous. The DTBB ligands in 1 and 2 are hexadentate, and the compounds have a channel structure in which solvent ethanol molecules are included. In compound 3, barium ion forms a complex 3-dimensional coordination polymer where both the carboxylate and the sulfur centers of the DTBB ligands (which are hepta- and octadentate) coordinate to the metal.

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“…It rather pro ceeds on an extracellular organic network which consists of phospho-and glycoproteins of unusual composition [1][2][3][4][5][6][7]. The role of these matrix pro teins during hard tissue form ation, especially du ring mineralization, is still obscure.…”

Section: Introductionmentioning

confidence: 99%

Phosphohydrolase Activities in Developing and Mature Dental Tissues

Warth

Jeck

1990

Zeitschrift Für Naturforschung C

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Phosphohydrolases, Dental Tissues, Tooth D evelopm ent, MineralizationIn the course o f the odontogenesis o f bovine incisors several clearly distinguishable phos phohydrolase activities are observed in the pulp and in dental hard tissues. Using various sub strates and inhibitors, unspecific alkaline phosphatase, two isoenzymes o f acid phosphatase, Ca2+-activated ATPase and inorganic pyrophosphatase are characterized. The enzymatic ac tivity o f alkaline phosphatase in pulp and hard tissues is significantly high at the beginning o f dentine and enamel mineralization. The specific activity o f this enzyme decreases quite fast with the beginning o f root form ation, then more slowly, until it reaches a constant final value. Histochemical studies show that during mineralization the maximum o f alkaline phosphatase activity is in the subodontoblasts. Lower enzyme concentrations are found in the stratum intermedium and in the outer enamel epithelium during that process.The specific activities o f ATPase, acid phosphatases and pyrophosphatase show little tem poral variation during tooth developm ent, but they also appear in a characteristic spatial pattern in the dental tissues.

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Molekulare Mechanismen der Biomineralisation bei der Bildung von Kalkschalen

Cited by 17 publications

References 78 publications

Structural diversity of biogenic carbonate particles in microbial mats

Structural diversity of biogenic carbonate particles in microbial mats

Reactions of 2-Mercaptobenzoic Acid with Divalent Alkaline Earth Metal Ions: Synthesis, Spectral Studies, and Single-Crystal X-ray Structures of Calcium, Strontium, and Barium Complexes of 2,2‘-Dithiobis(benzoic acid)^,

Phosphohydrolase Activities in Developing and Mature Dental Tissues

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Molekulare Mechanismen der Biomineralisation bei der Bildung von Kalkschalen

Cited by 17 publications

References 78 publications

Structural diversity of biogenic carbonate particles in microbial mats

Structural diversity of biogenic carbonate particles in microbial mats

Reactions of 2-Mercaptobenzoic Acid with Divalent Alkaline Earth Metal Ions: Synthesis, Spectral Studies, and Single-Crystal X-ray Structures of Calcium, Strontium, and Barium Complexes of 2,2‘-Dithiobis(benzoic acid),

Phosphohydrolase Activities in Developing and Mature Dental Tissues

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Reactions of 2-Mercaptobenzoic Acid with Divalent Alkaline Earth Metal Ions: Synthesis, Spectral Studies, and Single-Crystal X-ray Structures of Calcium, Strontium, and Barium Complexes of 2,2‘-Dithiobis(benzoic acid)^,