Esterification of Chlorophyllide in Prolamellar Body (PLB) and Prothylakoid (PT) Fractions from 4̂ vena sativa Etioplasts
نویسندگان
چکیده
Prolamellar Bodies, Thylakoids, Chlorophylls Etioplast membranes were fractionated into enriched prothylakoid (PT) and prolamellar body fraction (PLB) by known procedures [2]. The photoconversion of Protochlide to Chlide was 77% in the PT fraction but only 65% in the PLB fraction with optimum NADPH concentrations. The subsequent esterification reaction proceeds in both fractions indicating that the enzyme chlorophyll synthetase is present in both fractions. In the PLB fraction, 10-15% more Chip is formed than in the PT fraction. It is concluded that the concentration of the endogenous phytol precursor is higher in the membranes still present in the PLB fraction than in the PT fraction.
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