Klee H J, Hayford M B, Kretzmer K A, Barry G F, Kishore G M
Monsanto Company, Chesterfield, Missouri 63198.
Plant Cell. 1991 Nov;3(11):1187-93. doi: 10.1105/tpc.3.11.1187.
Synthesis of the phytohormone ethylene is believed to be essential for many plant developmental processes. The control of ripening in climacteric fruits and vegetables is among the best characterized of these processes. One approach to reduce ethylene synthesis in plants is metabolism of its immediate precursor, 1-aminocyclopropane-1-carboxylic acid (ACC). Soil bacteria containing an enzyme, ACC deaminase, were identified by their ability to grow on ACC as a sole nitrogen source. The gene encoding ACC deaminase was cloned and introduced into tomato plants. Reduction in ethylene synthesis in transgenic plants did not cause any apparent vegetative phenotypic abnormalities. However, fruits from these plants exhibited significant delays in ripening, and the mature fruits remained firm for at least 6 weeks longer than the nontransgenic control fruit. These results indicated that ACC deaminase is useful for examining the role of ethylene in many developmental and stress-related processes in plants as well as for extending the shelf life of fruits and vegetables whose ripening is mediated by ethylene.
植物激素乙烯的合成被认为对许多植物发育过程至关重要。在这些过程中，跃变型水果和蔬菜成熟的调控是最具特征的之一。减少植物中乙烯合成的一种方法是代谢其直接前体1-氨基环丙烷-1-羧酸（ACC）。通过在以ACC作为唯一氮源的培养基上生长的能力，鉴定出了含有ACC脱氨酶的土壤细菌。编码ACC脱氨酶的基因被克隆并导入番茄植株中。转基因植株中乙烯合成的减少并未导致任何明显的营养表型异常。然而，这些植株的果实成熟明显延迟，并且成熟果实比非转基因对照果实至少保持坚挺6周。这些结果表明，ACC脱氨酶可用于研究乙烯在植物许多发育和胁迫相关过程中的作用，以及延长由乙烯介导成熟的水果和蔬菜的货架期。
