Electric field strength of membrane lipids from vertebrate species: membrane lipid composition and Na+-K+-ATPase molecular activity.
Electric field strength of membrane lipids from vertebrate species: membrane lipid composition and Na+-K+-ATPase molecular activity.
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脊椎动物膜脂的电场强度：膜脂组成和 Na -K -ATP 酶分子活性。
DOI：
10.1152/ajpregu.00434.2004
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
R. Clarke
中科院分区：
文献类型：
--
作者：
T. Starke;N. Turner;P. Else;R. Clarke
膜内电场强度很可能是活细胞中离子转运膜蛋白活性的决定因素。在没有任何跨膜电位或表面电位的情况下，其大小由膜脂质成分及其相关水合水的偶极电位决定。在这里，我们已经使用了荧光方法来量化的偶极电位的囊泡从肾脏和脑的11种不同的动物物种从四个不同的脊椎动物类提取的脂质形成。将偶极电位与脂肪酸组成和每种制剂的Na（+）-K（+）-ATP酶分子活性进行比较。发现偶极电位的大小在所有动物物种中相对恒定，即，对于由总膜脂质制备的囊泡为236-334 mV，对于单独的磷脂为223-256 mV。单独磷脂的显著较低值可能与胆固醇和/或其他常见可溶性脂质分子从膜中的去除有关。令人惊讶的是，没有发现偶极电位对脂肪酸组成的显着依赖性。然而，这可能是由于脂质头基组成的伴随补偿变化造成的。Na（+）-K（+）-ATP酶的分子活性随偶极电位的增加而增加。在大范围的动物物种中，偶极电位保持在相对恒定的值，这一事实表明，它可能在确保膜内正确的离子泵构象和功能方面发挥重要作用。
Intramembrane electric field strength is a very likely determinant of the activity of ion-transporting membrane proteins in living cells. In the absence of any transmembrane electrical potential or surface potential, its magnitude is determined by the dipole potential of the membrane's lipid components and their associated water of hydration. Here we have used a fluorometric method to quantify the dipole potential of vesicles formed from lipids extracted from kidney and brain of 11 different animal species from four different vertebrate classes. The dipole potential was compared with the fatty acid composition and with the Na(+)-K(+)-ATPase molecular activity of each preparation. The magnitude of the dipole potential was found to be relatively constant across all animal species, i.e., 236-334 mV for vesicles prepared from the total membrane lipids and 223-256 mV for phospholipids alone. The significantly lower value for phospholipids alone is potentially related to the removal of cholesterol and/or other common soluble lipid molecules from the membrane. Surprisingly, no significant dependence of the dipole potential on fatty acid composition was found. This may, however, be due to concomitant compensatory variations in lipid head group composition. The molecular activity of the Na(+)-K(+)-ATPase was found to increase with increasing dipole potential. The fact that the dipole potential is maintained at a relatively constant value over a wide range of animal species suggests that it may play a fundamental role in ensuring correct ion pump conformation and function within the membrane.
影响因子：
3.4
作者：
SMABY, JM;BROCKMAN, HL
通讯作者：
BROCKMAN, HL
DOI：
10.1146/annurev.bb.15.060186.001115
发表时间：
1986
期刊：
Annual review of biophysics and biophysical chemistry
影响因子：
--
作者：
B. Honig;W. Hubbell;R. Flewelling
通讯作者：
B. Honig;W. Hubbell;R. Flewelling
含有一个或两个二十二碳六烯酰基链的磷脂酰胆碱对磷脂单层和双层性质的比较。
DOI：
10.1016/0005-2736(95)00058-b
发表时间：
1995
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Zerouga,M;Jenski,LJ;Stillwell,W
通讯作者：
Stillwell,W