Post Harvest Plant Physiology Laboratory, Beltsville Agricultural Research Center, Beltsville, Maryland 20705.
Plant Physiol. 1977 Sep;60(3):402-6. doi: 10.1104/pp.60.3.402.
Shake cultures, in contrast to static cultures of Penicillium digitatum grown in liquid medium, were induced by methionine to produce ethylene. The induction was concentration-dependent, and 7 mM was optimum for the methionine effect. In the presence of methionine, glucose (7 mM) enhanced ethylene production but did not itself induce ethylene production. The induction process lasted several hours, required the presence of viable mycelium, exhibited a lag period for ethylene production, and was effectively inhibited by cycloheximide and actinomycin D. Thus, the methionine-induced ethylene production appeared to involve induction of an enzyme system(s). Methionine not only induced ethylene production but was also utilized as a substrate since labeled ethylene was produced from [(14)C]methionine.Following induction by the fungus, filtrates of induced shake cultures also evolved ethylene in increasing amounts by both enzymic and monenzymic reactions. Tracer experiments indicated that the ethylene released by the filtrate was derived from a fungal metabolite of methionine and not directly from methionine.
与在液体培养基中静态培养的青霉相比，摇瓶培养的青霉经蛋氨酸诱导后可产生乙烯。这种诱导作用具有浓度依赖性，蛋氨酸的最佳效应浓度为 7mM。在蛋氨酸存在的情况下，葡萄糖（7mM）可增强乙烯的产生，但自身不能诱导乙烯的产生。诱导过程持续数小时，需要有活力的菌丝体存在，表现出乙烯产生的滞后期，并且环已酰亚胺和放线菌素 D 可有效抑制诱导过程。因此，蛋氨酸诱导的乙烯产生似乎涉及诱导一个酶系统。蛋氨酸不仅诱导了乙烯的产生，而且还被用作底物，因为从 [(14)C]蛋氨酸中产生了标记的乙烯。真菌诱导后，诱导摇瓶培养的滤液也通过酶促和单酶反应以递增的量产生乙烯。示踪实验表明，滤液中释放的乙烯来源于蛋氨酸的真菌代谢物，而不是直接来源于蛋氨酸。
