Early Changes in the Envelope Permeability of Developing Chloroplasts

Abstract

Application of the technique of silicone oil centrifugal filtration has shown that for some compounds, particularly oxaloacetate and succinate, there is a pronounced increase in permeability after 1–2 h of greening. Other compounds such as malate, glycine, and glutamate are progressively less permeable during plastid morphogenesis. Alanine, aspartate, and 3-phosphoglycerate show an initial decline in permeability after 1 h illumination but ready uptake into 2–4 h etiochloroplasts. There is also evidence that a translocator system for dicarboxylic acids involving malate exists within the plastid envelopes of Avena.