Acid-bath Phosphorylation in Heptane-extracted Chloroplasts.

When spinach (Spinacia oleracea) chloroplast fragments were lyophilized and extracted with n-heptane, acid-bath phosphorylation was significantly reduced. Phosphorylation could be restored to these chloroplasts, if the extracted material (containing quinones, carotenoids, and other lipids) was added back to dry preparation before rehydration. The results reported suggest it was not quinones which were required for restoration of acid-bath phosphorylation but lipids. It is suggested that the lipids which were extracted by n-heptane serves as structural role in the thylakoid membrane.