Search results for "Antimycin A"
showing 4 items of 4 documents
Photoreceptors and respiratory electron flow involvement in the activity of acifluorfen-methyl and LS 82-556 on nonchlorophyllous soybean cells
1987
Abstract The diphenyl ether acifluorfen-methyl [AFM; methyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate] and the pyridine derivative LS 82-556 [( S )-3- N -(methylbenzyl)carbamoyl-5-propionyl-2,6-lutidine] induce light-dependent polyunsaturated fatty acid peroxidation, leading to general membrane disruption. Although devoid of functional chloroplasts, cultured soybean cells are sensitive to AFM and LS 82-556 only in the light. The possible involvement of carotenoids and respiratory electron flow was examined by monitoring ethane evolution, fluorescein release, and dry weight/fresh weight ratio alteration. Herbicide effects on cells exposed to white light or blue light (380–540 n…
Evaluation of whole antioxidant defenses of human mononuclear cells by a new in vitro biological test: lack of correlation between erythrocyte and mo…
2009
1873-2933 (Electronic) Journal Article; OBJECTIVES: This work aims to evaluate the resistance of mononuclear cells to oxidative stress using a "KRL" test, formerly utilized to evaluate the resistance of erythrocyte to free radicals. METHODS: The "KRL" test evaluates the resistance to lysis of cells treated by free radicals generated under standardized conditions. RESULTS: We defined new analytical parameters (level of radical production, time course, number of cells) to obtain an accurate assay determining the resistance to oxidative stress of mononuclear cells, in comparison to that of erythrocytes. This test allows the evaluation of change in the redox state of mononuclear cells (improved…
Fluorescence induction kinetics as a tool to detect a chlororespiratory activity in the prasinophycean alga, Mantoniella squamata
1990
Abstract Pulse-modulated fluorescence measuring systems were used to study the fluorescence induction kinetics of the primitive prasinophycean alga, Mantoniella squamata . DCMU-treated cells show a very strong non-photochemical quenching which is insensitive to uncouplers and can not be attributed to state transitions or photoinhibition. In order to analyze the origin for this quenching, different inhibitors of the photosynthetic electron flow were applied. It was found that DCCD, an inhibitor of the ATP-synthase as well as of the cytochrome- c oxidase, enhances the fluorescence quenching, whereas antimycin A, which blocks the cyclic electron flow around PS I, stimulates it. The effect of b…
Two changes of the same nucleotide confer resistance to diuron and antimycin in the mitochondrial cytochrome b gene of Schizosaccharomyces pombe
1988
AbstractDiuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) and antimycin, both inhibitors of mitochondrial respiration, block electron flow between cytochromes b and c1. Mutants resistant to either drug have been selected using Schizosaccharomyces pombe strains with an extrachromosomally inherited mutator. In analogy to Saccharomyces cerevisiae these mutational sites were assumed to map in the cytochrome b gene. DNA sequence analysis showed that two changes in the same nucleotide are responsible for resistance to antimycin and diuron. Analysis of resistant and sensitive progeny of crosses between the mutants and the wild type confirmed the correlation between mutational alteration and resista…