Preparation of Physiologically Active Chloroplasts from Arabidopsis

Only structurally intact chloroplasts with a functional envelope exhibit metabolic activities comparable to those of the original tissues. Therefore, the most important objectives that should guide the isolation of chloroplasts from any plant species are then morphological and physiological integrity The use of intact chloroplasts is absolutely essential for studying processes like light-driven CO2 fixation, CO_2- dependent O2 evolution, zn organello RNA and protein synthesis, import of cytoplasmically made polypeptides into chloroplasts, or mcorporation of labeled precursors to dissect the enzymatic machinery involved m fatty acid biosynthesis and fatty acid incorporation into chloroplast lipids In some plant species, like spinach or pea, highly active chloroplasts can be obtained by followmg several simple rules: