Elevating the Vitamin E Content of Plants Through Metabolic Engineering

作者：David K. Shintani, Dean DellaPenna · 发表于：Science · 年份：1998 · DOI：10.1126/science.282.5396.2098 · 被引用次数：528 · 研究领域：Photosynthetic Processes and Mechanisms、Microbial Metabolic Engineering and Bioproduction、Antioxidant Activity and Oxidative Stress

alpha-Tocopherol (vitamin E) is a lipid-soluble antioxidant synthesized only by photosynthetic organisms. alpha-Tocopherol is an essential component of mammalian diets, and intakes in excess of the U.S. recommended daily allowance are correlated with decreased incidence of a number of degenerative human diseases. Plant oils, the main dietary source of tocopherols, typically contain alpha-tocopherol as a minor component and high levels of its biosynthetic precursor, gamma-tocopherol. A genomics-based approach was used to clone the final enzyme in alpha-tocopherol synthesis, gamma-tocopherol methyltransferase. Overexpression of gamma-tocopherol methyltransferase in Arabidopsis seeds shifted oil compositions in favor of alpha-tocopherol. Similar increases in agricultural oil crops would increase vitamin E levels in the average U.S. diet.