Photo-induced destruction of DOPA-melanin

Studies of the effect of illumination at different wavelengths revealed a high stability of DOPA-melanin to the visible light. Contrariwise, UV-visible light of high intensity upon prolonged (many hours) illumination caused a significant bleaching of the diluted aqueous solution of the pigment. The absorption spectrum of DOPA-melanin in the UV- and IR-regions did not differ from the initial one; however, the illuminated pigment acquired an ability for fluorescence. Stepwise gel chromatography on Toyopearl-55 and Toyopearl-40 columns resulted in three fractions of photobleached DOPA-melanin which differed in their molecular masses, absorption spectra (UV, IR) and fluorescence. It was concluded that the photoinduced bleaching of DOPA-melanin was mainly due to the pigment depolymerization. A possible mechanism of melanin photodestruction is discussed.     

The role of free radical oxidation in the regulation of growth and lipid formation in eukaryotic and prokaryotic organisms

The review considers the effect of free-radical oxidation on the growth of microorganisms, intensity of their metabolism, and composition of the membrane lipids. Using both own research evidence and this presented in the literature, the authors put forward a hypothesis about a certain correlation between physico-chemical properties of the membrane lipids and the intensity of the growth of eucaryotic and procaryotic microorganisms.     

Cyanine-dye-modified 2′-deoxyuridine-5′-triphosphates: Synthesis,applications, and linker effect on substrate properties for Taq DNA polymerase

A number of fluorescently labeled nucleoside triphosphates containing electroneutral indodicarbocyanine dye (Cy) have been synthesized. The dye has been attached to the C5 position of pyrimidine through the transalkene linkers of different structure. The synthesized labeled nucleoside triphosphates have been tested as substrates for Taq polymerase in PCR using the “TB-biochip” test system.     

Features of the Formation of Microbiomes in Two Types of Soils under Pine Provenance Trials of Pinus sibirica Du Tour and Pinus koraiensis Siebold et Zucc.

Biology Bulletin - The effect of pine provenance trials of Pinus sibirica Du Tour and Pinus koraiensis Siebold et Zucc. grown in Krasnoyarsk and Khabarovsk krais on the chemical and biological...     

Amplification of intermethylated sites experimental design and results analysis with <Emphasis Type="Italic">AIMS in silico</Emphasis> computer software

Amplification of intermethylated sites (AIMS) is a powerful tool for differential methylation screening of genomes. Its applications have nevertheless been limited until recently for the absence of systemic approach to AIMS experimental design and of appropriate computer software for the analysis of AIMS results. We have developed AIMS in silico computer suggestion tool capable of predicting possible experimental outcomes, which assists in designing AIMS experiments depending on the research aims and available instrumentation, and in analyzing experimental results from the point of view of genomic locations of the DNA fragments under study. With AIMS in silico we have characterized qualitatively and quantitatively AIMS products obtainable under different conditions; to ease experimental design we demonstrate AIMS products hierarchical structure. We discuss examples of designing AIMS experiments and of results analysis as well as possible relative to AIMS alternative approaches to differential methylation screening. AIMS in silico computer software is intended to standardize AIMS applications and to turn it into one of the principal approaches towards cancer epigenomes studies as well as towards diagnostics in oncology, including early screening.     

Nonenzymatic reduction of methemoglobin by free radical forms of NADH and riboflavin]

Nonenzymatic reduction of methemoglobin (met-Hb) is effectively catalyzed by NADH and riboflavin (RF). At low concentrations of met-Hb the EPR spectra of the ternary complex are characterized by an increased, whereas those at high met-Hb concentrations--by a decreased intensity of the RF semiquinone signal, which suggests that the met Hb reduction by a Leu-form of RF proceeds at a higher rate than that by the RF semiquinone radical. Riboflavin also accelerates the met-Hb reduction by a NADH-Fe2+ or NADH-Fe(2+)-EDTA mixture. It was found that the rate of met-Hb reduction by the organic radical increases in the following order: NAD. < RF H. < RF H2.