Biotechnology Research Institute, National Key Facility of Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Transgenic Res. 2013 Oct;22(5):1021-8. doi: 10.1007/s11248-013-9713-8. Epub 2013 May 4.
Tocochromanol, or vitamin E, plays a crucial role in human and animal nutrition and is synthesized only by photosynthetic organisms. γ-Tocopherol methyltransferase (γ-TMT), one of the key enzymes in the tocopherol biosynthetic pathway in plants, converts γ, δ-tocopherols into α-, β-tocopherols. Tocopherol content was investigated in 15 soybean cultivars and GmTMT2 was isolated from five varieties based on tocopherol content. GmTMT2a was expressed in E. coli and the purified protein effectively converted γ-tocopherol into α-tocopherol in vitro. Overexpression of GmTMT2a enhanced α-tocopherol content 4-6-fold in transgenic Arabidopsis, and α-tocopherol content increased 3-4.5-fold in transgenic maize seed, which correlated with the accumulation of GmTMT2a. Transgenic corn that is α-tocopherol-rich may be beneficial for animal health and growth.
生育三烯酚，或维生素 E，在人类和动物营养中起着至关重要的作用，只能由光合生物合成。γ-生育酚甲基转移酶（γ-TMT）是植物生育酚生物合成途径中的关键酶之一，它将γ、δ-生育酚转化为α、β-生育酚。对 15 个大豆品种的生育酚含量进行了研究，并根据生育酚含量从五个品种中分离出 GmTMT2。GmTMT2a 在大肠杆菌中表达，纯化后的蛋白在体外有效地将γ-生育酚转化为α-生育酚。GmTMT2a 的过表达使转基因拟南芥中的α-生育酚含量增加了 4-6 倍，转基因玉米种子中的α-生育酚含量增加了 3-4.5 倍，这与 GmTMT2a 的积累有关。富含α-生育酚的转基因玉米可能有益于动物的健康和生长。
