Lower activation energy for sliding of F-actin on a less thermostable isoform of carp myosin.
Lower activation energy for sliding of F-actin on a less thermostable isoform of carp myosin.
复制标题
F-肌动蛋白在耐热性较差的鲤鱼肌球蛋白亚型上滑动的活化能较低。
DOI：
10.1093/oxfordjournals.jbchem.a021480
复制
发表时间：
1996
影响因子：
2.7
通讯作者：
S. Watabe
中科院分区：
文献类型：
--
作者：
S. Chaen;M. Nakaya;X. F. Guo;S. Watabe
我们已经研究了温度依赖性的滑动速度的荧光F-肌动蛋白分离肌球蛋白从10摄氏度和30摄氏度的驯化鲤鱼。滑动的F-肌动蛋白的活化能分别为63和111千焦/摩尔的10摄氏度和30摄氏度的驯化鲤鱼肌球蛋白，分别。从10摄氏度和30摄氏度的适应鲤鱼肌球蛋白的滑动速度的Arrhenius图显示相交在高温（约30摄氏度）。通过测量Ca（2-）-ATP酶活性估计的热稳定性低于肌球蛋白从10 ℃-比30 ℃-驯化鲤鱼。我们认为，在冷驯化鲤鱼肌球蛋白的热稳定性较低的结构的结果在一个减少的激活能的收缩过程中，这使得F-肌动蛋白滑动快速，即使在低温下。
We have examined the temperature-dependence of sliding velocity of fluorescent F-actin on myosins isolated from 10 degrees C- and 30 degrees C-acclimated carp. Activation energies for the sliding of F-actin were 63 and 111 kJ/mol for the 10 degrees C- and 30 degrees C-acclimated carp myosins, respectively. Arrhenius plots of the sliding velocity from 10 degrees C- and 30 degrees C-acclimated carp myosin were shown to intersect at high temperature (about 30 degrees C). The thermostability estimated by measuring the Ca(2-)-ATPase activity was less for myosin from 10 degrees C- than 30 degrees C-acclimated carp. We suggest that a less thermostable structure in cold-acclimated carp myosin results in a reduced activation energy for the contractile process, which allows the F-actin to slide fast even at low temperatures.