[Photo-dependent conversions of cytochrome f in bean chloroplasts and leaves treated with polyene antibiotics].
The photo-dependent absorption changes of cytochrome f in bean chloroplasts and native leaves treated with the polyene antibiotics surgumycin and filipin were studied. Upon incubation of the chloroplasts or leaves with the antibiotics the value of the photo-induced signal of cytochrome f decreased considerably; however, the kinetics of the cytochrome oxidation under the effect of the exciting light and dark reduction remained unchanged. An addition of plastocyanin to the suspension of the antibiotic-treated chloroplasts, which contained no artificial donors and acceptors, only slightly increased the absolute value of the photo-induced signal of cytochrome f. An addition of plastocyanin to the chloroplasts containing the dichlorophenolindophenol-ascorbate-methylviologen system, sharply changed the kinetics of the cytochrome f photoconversions. A simultaneous registration of the photo-induced signal of cytochrome f and the photochemical activity of photosystem I of the antibiotic-treated chloroplasts revealed differences in the degree of inhibition of the photosystem I activity and decrease of the absolute value of the cytochrome f signal. The data obtained are discussed in terms of possible alternative pathways of electron transfer in the part of the electron transporting chain under study.
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002736:Chloroplasts / Q000187:drug effects / Q000378:metabolism*; D003580:Cytochromes / Q000378:metabolism*; D004579:Electron Transport; D005372:Filipin / Q000494:pharmacology*; D007700:Kinetics; D008027:Light; D010944:Plants; D011090:Polyenes / Q000494:pharmacology*; D013053:Spectrophotometry
D000900:Anti-Bacterial Agents; D003580:Cytochromes; D011090:Polyenes; D005372:Filipin
Fotozavisimye prevrashcheniia tsitokhroma f v khloroplastakh i list'iakh bobov, obrabotannykh polienovymi antibiotikami.