Noji M, Saito M, Nakamura M, Aono M, Saji H, Saito K
Graduate School of Pharmaceutical Sciences, Department of Molecular Biology and Biotechnology, Chiba University, Yayoi-cho 1-33, Inage-ku, Chiba 263-8522, Japan.
Plant Physiol. 2001 Jul;126(3):973-80. doi: 10.1104/pp.126.3.973.
Cysteine (Cys) synthase [O-acetyl-L-Ser(thiol)-lyase, EC 4.2.99.8; CSase] is responsible for the final step in biosynthesis of Cys. Transgenic tobacco (Nicotiana tabacum; F(1)) plants with enhanced CSase activities in the cytosol and in the chloroplasts were generated by cross-fertilization of two transformants expressing cytosolic CSase or chloroplastic CSase. The F(1) transgenic plants were highly tolerant to toxic sulfur dioxide and sulfite. Upon fumigation with 0.1 microL L(-1) sulfur dioxide, the Cys and glutathione contents in leaves of F(1) plants were increased significantly, but not in leaves of non-transformed control plants. Furthermore, the leaves of F(1) plants exhibited the increased resistance to paraquat, a herbicide generating active oxygen species.
半胱氨酸(Cys)合酶[O-乙酰-L-丝氨酸(硫醇)裂解酶,EC 4.2.99.8;CSase]负责半胱氨酸生物合成的最后一步。通过将两个分别表达胞质CSase或叶绿体CSase的转化体进行杂交,培育出了在胞质溶胶和叶绿体中CSase活性增强的转基因烟草(烟草;F(1))植株。F(1)转基因植株对有毒的二氧化硫和亚硫酸盐具有高度耐受性。在用0.1微升/升的二氧化硫熏蒸后,F(1)植株叶片中的半胱氨酸和谷胱甘肽含量显著增加,但未转化的对照植株叶片中则没有。此外,F(1)植株的叶片对百草枯(一种产生活性氧的除草剂)表现出更强的抗性。