Rotational motion of the sarcoplasmic reticulum Ca2+-ATPase.
Rotational motion of the sarcoplasmic reticulum Ca2+-ATPase.
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肌浆网 Ca2-ATP 酶的旋转运动。
DOI：
10.1073/pnas.75.11.5488
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发表时间：
1978
影响因子：
11.1
通讯作者：
C. Hidalgo
中科院分区：
文献类型：
--
作者：
D. D. Thomas;C. Hidalgo
使用饱和转移电子顺磁共振，我们已经检测到的自旋标记的旋转运动刚性连接到肌浆网Ca 2 +-ATP酶（ATP磷酸水解酶，EC 3.6.1.3）。在4 ℃时，光谱表明60微秒的有效旋转相关时间，通过与从理论计算和从模型系统的实验中获得的参考光谱进行比较来确定。这种运动似乎对应于酶相对于膜的旋转，因为当膜片段通过沉降固定时，运动持续，并且当多肽链而不是膜囊泡通过戊二醛交联时，运动停止。酶的旋转流动性随着温度的升高而增加，当温度超过20 ℃时，这种增加变得更加平缓;先前已经观察到脂质流动性和酶活性的相同类型的温度依赖性。
Using saturation transfer electron paramagnetic resonance, we have detected the rotational motion of a spin label rigidly attached to the sarcoplasmic reticulum Ca2+-ATPase (ATP phosphohydrolase, EC 3.6.1.3). At 4 degrees C, the spectrum indicates an effective rotational correlation time of 60 microsec, determined by comparison with reference spectra obtained from theoretical calculations and from experiments on model systems. This motion appears to correspond to rotation of the enzyme with respect to the membrane, because the motion persists when the membrane fragments are immobilized by sedimentation and the motion stops when the polypeptide chains, but not the membrane vesicles, are crosslinked by glutaraldehyde. The rotational mobility of the enzyme increases with increasing temperature, and this increase becomes more gradual when the temperature exceeds 20 degrees C; the same kind of temperature dependence has been observed previously for lipid fluidity and enzymatic activity.