Research Institute for Biochemical Regulation, Faculty of Agriculture, Nagoya University, Nagoya, Japan.
Planta. 1972 Jun;105(2):165-73. doi: 10.1007/BF00385575.
Ethylene production was induced in excised hypocotyl segments of etiolated mungbean seedlings in response to exogenous auxin. 1,2,3,4-(14)C-Methionine was efficiently incorporated into C2H4, although cold methionine added at substrate level did not enhance C2H4 production. Incorporation of labeled glucose into C2H4 was reduced when hypocotyl segments were incubated with cold methionine and homoserine, but the rate of labeling of CO2 was not affected. Feeding of labeled glucose to segments resulted in production of labeled methionine both in the presence and the absence of auxin, and auxin did not affect rate of methionine synthesis from glucose. The decrease in the amount of endogenous methionine during auxin treatment approximated the amount of C2H4 produced. The timecourse pattern of incorporation of radioactivity from labeled methionine into C2H4 during removal or re-addition of auxin was very similar to that of C2H4 production. The role of endogenous methionine as a C2H4 precursor is discussed.
乙烯的产生是在对外部生长素的反应中，由黄化绿豆幼苗的切下的下胚轴片段诱导的。尽管在基质水平上添加冷的蛋氨酸不会增强乙烯的产生，但 1,2,3,4-(14)C-蛋氨酸被有效地掺入到 C2H4 中。当下胚轴片段与冷蛋氨酸和高丝氨酸一起孵育时，标记的葡萄糖掺入到 C2H4 中的速率降低，但 CO2 的标记速率不受影响。将标记的葡萄糖供给片段会导致在有和没有生长素的情况下产生标记的蛋氨酸，并且生长素不会影响从葡萄糖合成蛋氨酸的速率。在生长素处理期间内源性蛋氨酸的减少量与产生的乙烯量相近。在去除或重新添加生长素时，标记的蛋氨酸中的放射性掺入到 C2H4 中的时间进程模式与 C2H4 的产生非常相似。内源性蛋氨酸作为 C2H4 前体的作用被讨论。
