【摘要】 本试验研究了高温胁迫下小麦幼苗膜结合ATPase的动力学参数变化以及Ca²⁺对它的影响。主要结果如下:①高温胁迫下的Km值低于常温下的Km值。②Ca²⁺处理的Km值低于对照的Km值。③常迫下的V_max值高于高温下的V_max值。④Ca²⁺处理的V_max高于对照的V_max值。由此可以看出,高温胁迫下,ATPase与底物结合的亲和力增大了,但酶量减少了,使V_max值下降。Ca²⁺处理对两者都有正效应,因而对高温胁迫有减缓作用。更多还原

【Abstract】 The dynamic parameter changes of membrane-bound ATPase in wheat seedlings under high-temperature stress and the effect of Ca²⁺ on them are primarily investigated. The main results are as follows: 1) Km values of high-temperature stressed seedlings are lower than those of the seedlings grown in the normal temperature. 2) Km values of Ca²⁺ treated seed-lings are lower than those of the control. 3) Vmax values of normally grown seedlings are higher than those of the high-temperature stressed ones. 4) Vmax values of Ca²⁺treated seedlings are higher than those of the control. It is suggested that under high-temperature stress, 1) the compatibility between ATPase and its substrate is increased, but the decreased amount of the enzyme greatly reduces the Vmax value; 2) Ca²⁺treatment has positive effect on both of the Km and Vmax values, and thus reduces the damages from high-temperature stress.更多还原