Correlation between chlorophyllide esterification, Shibata shift and regeneration of protochlorophyllide650 in flash-irradiated etiolated barley leaves
Autor: | Siegrid Schoch, Vladimir Domanskii, N. G. Averina, Valentina Rassadina, Wolfhart Rüdiger |
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Rok vydání: | 2004 |
Předmět: |
Physiology
Stereochemistry Cell Biology Plant Science General Medicine Biology chemistry.chemical_compound Pigment Phytol Protochlorophyllide reductase Geranylgeraniol chemistry Protochlorophyllide visual_art Etiolation Genetics visual_art.visual_art_medium Kinetin sense organs Hordeum vulgare Nuclear chemistry |
Zdroj: | Physiologia Plantarum. 121:556-567 |
ISSN: | 1399-3054 0031-9317 |
Popis: | The pigments of etiolated leaves of barley (Hordeum vulgare L.) were analysed during dark periods after flash illumination, and the results were compared with in vivo spectroscopy of the leaves. Pretreatment of the leaves with kinetin slightly stimulated and pretreatment with NaF and anaerobiosis inhibited the esterification of chlorophyllide a (Chlide) at 10–40 min after the flash, whereas the rapid esterification within 30 s after the flash remained unchanged. Irrespective of pretreatment, the amount of esterified pigment was, at any time, identical with the amount of pigment that had shifted its absorption from 684 to 672 nm (Shibata shift). Cycloheximide (CHI) had only a small inhibitory effect on esterification, but drastically inhibited the hydrogenation of geranylgeraniol to phytol, bound to Chlide. The regeneration of long-wavelength protochlorophyllide a (Pchlide650) was stimulated by kinetin and inhibited by CHI and NaF. During the rapid phase (0–30 s after the flash), the esterification was faster than the regeneration of Pchlide650, and this, in turn, was faster than the formation of photoactive Pchlide. The kinetics changed after pretreatment with 5-aminolaevulinic acid: regeneration of Pchlide650 was the fastest reaction and the Shibata shift preceded the esterification of Chlide. The results are discussed as pigment exchange reactions at NADPH:protochlorophyllide oxidoreductase (POR; EC 1.6.99.1). |
Databáze: | OpenAIRE |
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