Matrices, living systems

Looking at the literature in the field of biomineralization, one notices, that the majority of articles is descriptive in nature. On the basis of electron micrographs or thin section studies, the intricate relationships between mineral phase and organic matrix are investigated. Other papers deal with the chemical composition of the mineralized tissue and the minerals. Only a few authors address themselves to the question of metal ion transport mechanisms in cellular systems and the solid state principles involved in mineral deposition on organic substrates. All three sets of information, however, are essential to understand calcification processes. It appears, therefore, that information on the functionality of metal ions in living systems and their role in mineral deposition are particularly desired in this area of research. 

Must the information content of a living system be held in a polymer If so, must it be a standard biopolymer Or can the information to support life be placed in a mineral form or in a matrix that is not molecularly related to Darwinian processes ... 

Simon, P. and Joner, E. (2008). Conceivable interactions of biopersistent nanoparticles with food matrix and living systems following from their physicochemical properties.. Food Nutr. Res. 47, 51-59. 

Biological membranes are by far the most important electrified interfaces in living systems. They consist of a bimolecular layer of lipids (the lipid bilayer) incorporating proteins. Lipid molecules are amphiphilic, that is, they consist of a hydro-phobic section (the hydrocarbon tail) and a hydrophilic section (the polar head). In biological membranes the two lipid monolayers are oriented with the hydrocarbon tails directed toward each other and the polar heads turned toward the aqueous solutions that are in contact with the two sides of the membrane. The resulting lipid bilayer is a matrix that incorporates different proteins performing a variety of functions. 

In summary, one might expect to find calcium-binding proteins playing six distinct roles in living systems 1. binding sites on the outer surface of plasma membranes, 2. transport carriers in cell membranes, 3. intracellular storage reservoirs of calcium, 4. intracellular receptors linked to calcium function (i.e., in contractile systems), 5. as part of matrix of mineralized tissues and, 6. as a co-factor in calcium-activated enzymes. 

The environmental impact of metallic contaminants in soils is dependent both on the chemical speciation of the metal and the response of the matrix to biological and physicochemical conditions. These factors are responsible for the mobilisation of the metal from the solid into the aqueous phase hence transport within the immediate vicinity, has an impact on the rate of dispersal, dilution, uptake and transfer into living systems. The impact of changing environmental conditions on the contaminant inventory can be to enhance or moderate these phenomena, with subsequent consequences for the broader risk assessment of the contaminants. During the last ten years, extensive research in analytical chemistry was initiated to develop highly specific and sensitive methods for measuring potentially harmful substances in various... 

One environmental concern is that around the world there are landfill areas where over the years chromite ore processing residues (COPR) have been dumped, and chromium from these landfills is being leached into the ground water. The environmental impact of chromium in soils and sediments is dependent on specia-tion and on the response of the matrix to biological and physico-chemical conditions. These factors control the mobilization of chromium from the solid into the aquatic phase and uptake and transfer into living systems (Hursthouse 2001). 

V. V, Zharkova, I. I., Shaitan, K. V, Sklyanchuk, E. D., Guryev, E. D. Fibrillar matrixes for tissue engineering constructions from poly(3-hydroxybutyrate) and its composites (In Rus). Technology of living systems. 2013,10(8), 74-79. 

In all of the multistep immobilized enzyme work done to date, theoretical or experimental, for modelling purposes or for applications, there exists one common factor the chemical reactions are affected by the diffusive processes so that the macroscopically observed kinetics are strongly perturbed by the incorporation of the enzymes into a gel. This perturbation is caused by the development of localized concentrations and concentration gradients within the gel which are quite different from that found in free solution. Only one instance appears to have been reported where exact modelling of real experimental data has been attempted. All other work has been either purely theoretical or qualitative interpretations of limited experimental data. There is still much to be learned of the role played by the gel matrix in affecting the overall kinetic performance of gel entrapped multienzyme systems before they can be well designed for applications or used with any confidence in a quantitative way as models for living systems. 

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