Terpenoid Metabolism in Plastids

Abstract

The synthesis of alpha-tocopherol from 2,3-dimethylphytylquinol and S-adenosyl-l-methionine was achieved using Capsicum annuum fruit chromoplasts. The enzymes involved in the cyclization (2,3-dimethyl-phytylquinol cyclase) and methylation (S-adenosyl methionine:gamma-tocopherol methyl-transferase) are both localized in the chromoplast membrane fraction (envelopes and/or a-chlorophyll lamellae), in contrast to the stroma fraction.