Search

Your search keyword '"Shubin V"' showing total 1,196 results
Start Over Author "Shubin V"
1,196 results on '"Shubin V"'

251. Effect of Ionophores on Activity of Na,Cl(HCO)-ATPase.

Author

Yurkiv, V., Melikhov, V., and Shubin, V.

Subjects
IONOPHORES, HISTAMINE, ADENOSINE triphosphatase, DINITROPHENOL, HYDROGEN-ion concentration
Abstract

We studied the effects of ionophores on activity of Na,Cl(HCO)-ATPase. The most significant effect on the activity of this enzyme was produced by protonophore 2,4-dinitrophenol. The effect of this drug largely depended on the cation and anion composition and pH of the incubation medium and its pH. Activity of Na,Cl(HCO)-ATPase increased at neutral and weakly alkaline pH and decreased at pH below 6.5-6.7. In control animals (without histamine injection) with very weak or absent Na,Cl(HCO)-ATPase activity, the observed effect of the protonophore on ATPase activity was also virtually absent. The stimulatory effect of other ionophores (monensine, valinomycin, and A) was significantly weaker and depended on pH of the incubation medium, its cationic and anionic composition, and concentration of these ionophores. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

299. An increase in the resistance of R-phycoerythrin to thermal aggregation by silver nanoparticles synthesized in nanochannels of the pigment.

Author

Bekasova, O., Borzova, V., Shubin, V., Kovalyov, L., Stein-Margolina, V., and Kurganov, B.

Subjects
SILVER nanoparticles, PHYCOERYTHRIN, THERMAL stability, LIGHT scattering, CIRCULAR dichroism
Abstract

R-phycoerithrin, a water soluble photosynthetic pigment of red algae, was used as a matrix and a reducer for the synthesis of Ag nanoparticles. The diameter of dominating Ag nanoparticles determined from the electron microscope images was 6.5 ± 0.5 nm. Dynamic light scattering in the regime of heating with a constant rate showed that the hydrodynamic radius of R-phycoerithrin molecules began to increase at a temperature of more than 50°C. The hydrodynamic radius of R-phycoerithrin with Ag nanoparticles synthesized in the inner cavity remained constant upon heating to 90°C. It was shown by circular dichroism that the temperature at which the portion of the denatured protein reached 50% was 51.7 ± 0.1°C for R-phycoerithrin and 58.0 ± 0.1°C for R-phycoerithrin with synthesized Ag nanoparticles. This indicated that thermal stability of R-phycoerythrin increased when its cavity was filled with an Ag nanoparticle. According to the comparative spectral studies of R-phycoerythrin before and after the synthesis of Ag nanoparticles and the heat treatment, we conclude that an increase in thermal stability of R-phycoerythrin is caused by chemical intramolecular cross-linking of a protein molecule with an Ag nanoparticle. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results