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1.
Martinovich G. G. Martinovich I. V. Vcherashniaya A. V. Shadyro O. I. Cherenkevich S. N. 《Biophysics》2016,61(6):963-970
Biophysics - Mechanisms of tumor-cell responses to 2-isopropyl-5-methyl-1,4-benzoquinone (thymoquinone) and 1,4-benzoquinone were studied using fluorescence and the inhibition assay. It was shown... 相似文献
2.
Further studies on the role of cell-wall-degrading enzymes in cell-wall loosening in oat coleoptiles
A fungal endo-ß-l,3-glucanase was compared with afungal exo-ß-1,3-glucanase with respect to their effectson elongation and cell-wall extensibility in oat coleoptilesegments. The exo-enzyme enhanced elongation and extensibilityof the cell wall. Its effect was not additive to the effectof indole-3-acetic acid when given together with the latter,at least during 3 hr of incubation. Endo-glucanase showed nosignificant effect on elongation and no interaction with theexo-enzyme. Auxin and exo-glucanase increased extensibilityof the cell wall. The exo-glucanase was separated by isoelectricfocusing. The two fractions which were separated and showedglucanase activity induced elongation and cell wall loosening. (Received March 16, 1970; ) 相似文献
3.
E A Grintsevich V V Senchuk A V Puchkaev O I Shadyro D I Metelitsa 《Bioorganicheskaia khimiia》2000,26(11):825-837
A comparative kinetic study on the poly(gallic acid disulfide) (poly(DSGA)) inhibition of the iodide ion oxidation and on the 2-hydroxy-3,5-di-tert-butyl-N-phenylaniline (butaminophene) inhibition of 3,3',5,5'-tetramethylbenzidine (TMB) oxidation involving human thyroid peroxidase (hTPO) and horseradish peroxidase (HRP) was performed. The inhibition processes were characterized with the inhibition constants Ki and stoichiometric inhibition coefficients f, indicating the number of radical particles perishing on one inhibitor molecule. In the case of poly(DSGA), the Ki values for the I- oxidation were 0.60 and 0.04 microM, and the coefficients f were 13.6 and 16.5 for hTPO and HRP, respectively, which evidences the regeneration and high effectiveness of the polymeric inhibitor. In the case of butaminophene, the Ki values for TMB oxidation were 38 and 46 microM for hTPO and HRP, respectively. The coefficients f were 1.33 and 1.47, respectively, to reveal that butaminophene does not regenerate. The inhibition mechanisms for I- and TMB oxidation involving the two peroxidases are discussed. 相似文献
4.
Metelitsa DI Naumchik IV Karaseva EI Polozov GI Shadyro OI 《Prikladnaia biokhimiia i mikrobiologiia》2003,39(4):401-412
Peroxidase-catalyzed oxidation of o-phenylene diamine (OPD) was competitively inhibited by trimethylhydroquinone (TMHQ), 4-tert-butylpyrocatechol (In5), and 4,6-di-tert-butyl-3-sulfanyl-1,2-dihydroxybenzene (In6). In6 was the most efficient inhibitor (Ki = 11 microM at 20 degrees C in 0.015 M phosphate-citrate buffer, pH 6.0). The effects of In5 and In6 were not preceded by periods of induction of OPD oxidation products (contrary to TMHQ). Peroxidase-catalyzed oxidation of tetramethylbenzidine (TMB) was non-competitively inhibited by In6 and 3-(2-hydroxyethylthio)-4,6-di-tert-butylpyrocatechol (In4), whereas o-aminophenol (OAP) acted as a mixed-type inhibitor. The effects of all three inhibitors were preceded by an induction period, during which TMB oxidation products were formed. Again, In6 was the most efficient inhibitor (Ki = 16 microM at 20 degrees C in 0.015 M phosphate-citrate buffer supplemented with 5% ethanol, pH 6.0). Judging by the characteristics of the inhibitors, taken in aggregate, it is advisable to use the pairs OPD-In5 and OPD-In6 in systems for testing the total antioxidant activity of biological fluids of humans. 相似文献
5.
Shadyro OI Sosnovskaya AA Edimecheva IP Ostrovskaya NI Kazem KM Hryntsevich IB Alekseev AV 《Bioorganic & medicinal chemistry letters》2007,17(22):6383-6386
The coenzymes Q and Vitamin K(3), as well as their synthetic analogues, have been found to inhibit free-radical processes of fragmentation of hydroxyl-containing organic compounds and oxidation of the latter by molecular oxygen. It has been established that the observed effects are due to the ability of quinones to oxidize the alpha-hydroxyl-containing carbon-centered radicals formed from the starting compounds. 相似文献
6.
Under the action of free-radical reaction initiators on membrane phospholipids, complex processes are taking place in both hydrophobic and hydrophilic parts of the phospholipids. Realization of these processes results in a mixture consisting of the initial lipids and their peroxidation and fragmentation products. Identification of compounds in such mixtures requires analytical methods of high sensitivity, reproducibility and accuracy to be applied. These properties are characteristic of the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) method. In the studies of radiation-induced free-radical transformations of phosphatidylglycerol, the MALDI-TOF MS in combination with thin layer chromatography (TLC) has been shown to be able to detect and identify products of free-radical transformations taking place in both hydrophilic and hydrophobic parts of the phospholipid. Thus, the MALDI-TOF MS can serve as a suitable analytical tool to investigate free-radical transformations of lipids. 相似文献
7.
Brinkevich SD Ostrovskaya NI Parkhach ME Samovich SN Shadyro OI 《Free radical research》2012,46(3):295-302
Effects of curcumin and related compounds on product formation in radiolysis of aerated and deaerated ethanol were studied. Ab initio calculations of enthalpy values relating to O-H bond dissociation and H-atom addition to > C = O bonds of the compounds under study have been performed. The obtained data allowed the conclusion that the presence of a 7-carbon chain containing conjugated > C = C < and > C = O bonds in the structures of curcumin and its analogues makes these compounds capable of inhibiting the reactions involving α-hydroxyl-containing carbon-centered radicals. This finding broadens the existing views concerning radical-regulating properties of curcuminoids, and it should be taken into account when practical use of these compounds is envisaged. 相似文献
8.
The activities of green cell-free extracts of spinach leavesin performing photochemical transphosphorylation, photosyntheticphosphorylation, the HILL reaction and the light-induced formationof the endogenous reducing substance (ascorbic acid) were followedin parallel during the growth process of the plant. There wasa certain parallelism between the development of the activitiesof photochemical transphosphorylation, of photo-synthetic phosphorylationand of the HILL reaction, activities being low in the earlierstage of growth, reaching a maximum just before efflorescence,and showing thereafter a more or less sharp decline. The activityin the light-induced formation of endogenous reducing substancewas undetectable for the first 35 day-period of growth, reacheda maximum about one week earlier than the other three activities,and again disappeared after 60 days of growth. (Received September 9, 1960; ) 相似文献
9.
It has been shown using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and its combination with thin-layer chromatography (TLC) that the action of the ascorbate/Fe(2+)/H(2)O(2) oxidizing system on cardiolipin and galactocerebroside results in the formation of phosphatidic acid (PA) and ceramide (Cer), respectively. These data, when combined with results obtained on radiolysis of similar substances, allowed the conclusion that the formation of PA and Cer occurs via an OH-induced fragmentation taking place in polar moiety of the starting substrates. 相似文献
10.
Brinkevich SD Boreko EI Savinova OV Pavlova NI Shadyro OI 《Bioorganic & medicinal chemistry letters》2012,22(7):2424-2427
The ability of ascorbic acid and a number of its derivatives to suppress replication of Herpes simplex virus type I was investigated in human rhabdomyosarcoma cell line. In parallel, interaction of the test compounds with carbon- and oxygen-centered radicals formed on radiolysis of hydroxyl-containing organic compounds was studied using the steady state radiolysis method. It has been shown that 2-O-glycoside of ascorbic acid, displaying marked antiviral properties against Herpes simplex virus type I, is also capable of inhibiting fragmentation and recombination reactions of α-hydroxyl-containing carbon-centered radicals while not affecting processes involving oxygen-centered radicals. 相似文献