Purification of Chloroplast Envelope, Thylakoids, and Stroma from Angiosperm Leaves

Abstract

Plant cell chloroplasts are bounded by a two-membrane envelope. Their photosynthetic function is based on the development of an operational large internal membrane network, called the thylakoids, and on enzymatic processes present in the chloroplast matrix, called the stroma. Thylakoid membranes are distinct from the chloroplast envelope, and their biogenesis is dependent on biosynthetic and transport activities specific of the chloroplast envelope. Starting with the isolation of intact chloroplasts, the method presents the separation by differential centrifugation of the three compartments. A protocol is detailed for leaves of spinach, Arabidopsis or pea.

Keywords: Chloroplast; Chloroplast fractionation; Differential centrifugation; Envelope; Membrane; Stroma; Thylakoids.