Photoreduction of Zinc Protopheophorbide b with NADPH-Protochlorophyllide Oxidoreductase from Etiolated Wheat (Triticum aestivum L.)
Autor: | Christer Sundqvist, Wolfhart Rüdiger, Siegrid Schoch, Margareta Ryberg, Michael Helfrich, Bengt Wiktorsson |
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Rok vydání: | 1995 |
Předmět: |
Chlorophyll
chemistry.chemical_classification Chlorophyll b Oxidoreductases Acting on CH-CH Group Donors Light Photochemistry chemistry.chemical_element Zinc Biology Biochemistry chemistry.chemical_compound Enzyme chemistry Protochlorophyllide Oxidoreductase Etiolation Etioplasts NADPH-protochlorophyllide oxidoreductase Oxidoreductases Triticum |
Zdroj: | European Journal of Biochemistry. 229:291-298 |
ISSN: | 1432-1033 0014-2956 |
Popis: | A preparation of prolamellar bodies from wheat etioplasts was used as a source for NADPH-protochlorophyllide oxidoreductase (pchlide reductase). The enzyme was solubilized with Triton X-100 after reduction of the endogenous photoconvertible protochlorophyllide a to chlorophyllide a by saturating illumination. Protochlorophylls a and b, protochlorophyllide a and zinc protopheophorbide b were added to the soluble enzyme preparation to determine if they were reduced in the dark or in the light. None of the compounds were reduced (with NADPH) in the dark; however, light-dependent reduction was demonstrated with protochlorophyllide a and zinc protopheophorbide b. The yield was approximately 50% for both substrates. Photoreduction did not occur with the esterified protochlorophylls a and b. Photoreduction of zinc protopheophorbide b, the zinc analogue of protochlorophyllide b, is the first demonstration of the reduction of a chlorophyll-b-related compound by pchlide reductase. |
Databáze: | OpenAIRE |
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