Biologically active organic species

Phosphazene Rings and High Polymers Linked to Transition Metals or Biologically Active Organic Species... 

ENDOR methods can be especially useful for investigating biological systems because powder-type spectra can yield isotropic and anisotropic coupling constants with a higher resolution and precision than can conventional ESR spectroscopy. Typical examples are the radical ions occurring as primary photoproducts in reaction centers of photosynthetic bacteria. Liquid-state ENDOR measurements have been made on biologically active organic species such as the vitamin quinones. 

A current area of interest is the use of AB cements as devices for the controlled release of biologically active species (Allen et al, 1984). AB cements can be formulated to be degradable and to release bioactive elements when placed in appropriate environments. These elements can be incorporated into the cement matrix as either the cation or the anion cement former. Special copper/cobalt phosphates/selenates have been prepared which, when placed as boluses in the rumens of cattle and sheep, have the ability to decompose and release the essential trace elements copper, cobalt and selenium in a sustained fashion over many months (Chapter 6). Although practical examples are confined to phosphate cements, others are known which are based on a variety of anions polyacrylate (Chapter 5), oxychlorides and oxysulphates (Chapter 7) and a variety of organic chelating anions (Chapter 9). The number of cements available for this purpose is very great. 

Fischer, brilliant results were achieved, and in succession the a-amylases of pig pancreas, of Bacillus subtilis, of human saliva, of human pancreas, and of Aspergillus oryzae, and the /3-amylase of malt, were successfully crystallized. Important biological deductions were gained from this study whereas the amylases of human pancreas and saliva cannot be distinguished from one another, amylases from pig pancreas and from human pancreas are different. These differences are manifested in molecular weight, crystalline forms, electrophoretic mobility, and influence of the pH on the activity however, all the amylases have the same specific biochemical action. The identity of the enzymes seems to be dependent on the species and not on the organ. Interest in biologically active proteins led Meyer to a study of the protein hormones, a field in which he was very active at the time of his death. 

Electron transfer (ET) is a key reaction in biological processes such as photosynthesis and respiration [1], Photosynthetic and respiratory chain redox proteins contain one or more redox-active prosthetic groups, which may be metal complexes or organic species. Since it is known from crystal structure analyses that the prosthetic groups often are located in the protein interior, it is likely that ET in protein-protein complexes will occur over large molecular distances ( > 10 A) [2-4],... 

Biological activity is an important indicator of the decomposition of soil organic matter within the soil. High biological activity promotes metabolism between soil and plants and is an essential part of sustainable plant production and fertiliser management. Earthworms, as a key species for soil macro-fauna, are an appropriate indicator of soil s biological activities due to their sensitivity to any kind of soil disturbance. Microbial activity of soils is an indicator of soil micro-fauna. Both indicators are reviewed below. 

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