Biological systems identification

Density-based methods Wave function-based methods Some technical aspects Excitations in various systems Excitations in metal clusters Excitations in semiconductor nanoparticles Excitations in organic and biological systems Identification of structure Dynamics in excited states Conclusions... 

Marmarelis, V.Z. 1977. A family of quasi-white random signals and its optimal use in biological system identification I. Theor. Biol. Cybem. 27 49. 

In as far as other analytical methods are concerned, many specific reactions have been elaborated for the quantitative determination of 2-deoxy aldoses. 2-Deoxy-D-ribose (2-deoxy-D-erythro-pentose), a compound which was recognized early as playing an important role in biological systems, has been of particular interest. Overend and Stacey (43) have given a critical review of the methods available until 1952 for the estimation of 2-deoxy pentoses. A recent summary of specific methods for the identification and quantitative estimation of the different classes of deoxy sugars has been prepared by Dische (13). 

To ensure microbial strains are viable and pure a suite of morphological, biochemical, and cytochemical tests are used to confirm characteristics specific to their taxons. A number of commercially available rapid identification kits are also employed for some common genera. In addition to these taxon specific tests, many of the cultures are tested for their fatty acid methyl ester (FAME) profiles using the commercial MIDI system. The FAME profiles can be compared to the MIDI database for species identification/confirmation purposes. The Biolog system, which yields a metabolic fingerprint of an organism, is another alternative for rapid identification. 

In situ generation of these cation-radicals has been used in their identification as biological metabolites. A valid alternative was to synthesize the cation-radical as a solid salt, isolate it, and investigate its reactions with various nucleophiles including DNA. Such studies were conducted to better understand the role of those intermediates in biological systems (Murata and Shine 1969, Ristagno and Shine 1971, Cremonesi et al. 1994, Stack et al. 1995). 

In this type of spin traps, 5,5-dimethyl-l-pyrroline-Af-oxide (DMPO) deserves particular mention. DMPO is widely employed as a spin trap in the detection of transient radicals or ion-radicals in chemical and biological systems (see, e.g., Siraki et al. 2007). Characteristic ESR spectra arising from the formation of spin adducts are used for identification of specific spin species. In common opinion, such identification is unambiguous. However, in reactions with superoxide ion (Villamena et al. 2004, 2007b), carbon dioxide anion-radical (Villamena et al. 2006), or carbonate anion-radical (Villamena et al. 2007a), this spin trap gives rise to two adducts. Let us consider the case of carbonate anion-radical. The first trapped product arises from direct addition of carbonate anion-radical, second adduct arises from partial decarboxylation of the first one. Scheme 4.25 illustrates such reactions based on the example of carbonate anion-radical. 

Santos AF, Zaltsman AB, Martin RC et al (2008) Angiogenesis an improved in vitro biological system and automated image-based workflow to aid identification and characterization of angiogenesis and angiogenic modulators. ASSAY Drug Devel Technol 6 693-710... 

The first observations of the additions of transient radicals to nitroso compounds (equation 60) and nitrones (equation 61) to form stable nitroxyl radicals, which could be conveniently detected by ESR for the identification of the transient radicals, were reported in the mid-1960s. This technique has been extensively applied in chemical "" and biological systems. " ... 

They are also potentially Interconvertible (5 ). Recent advances have allowed the Identification of IO2 in photochemical damage of biological systems by the use of quenchers W or D2O which enhances the lifetime of 02 (,]) Superoxide is detected in photc— oxidations by the use of the scavenging enzyme superoxlde dlsmutase (8). Important target molecules are proteins, lipids (especially cholesterol) and nucleic acids (, 9) but the... 

Vanin, A. F. (1967). Identification of divalent iron complexes with cysteine in biological systems by the EPR method. Biochemistry (USSR) 32, 228-232. 

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