Brown F F, Sussman I, Avron M, Degani H
Biochim Biophys Acta. 1982 Sep 9;690(2):165-73. doi: 10.1016/0005-2736(82)90319-4.
Glycerol diffusional permeabilities through the cytoplasmic cell membrane of Dunaliella salina, the cell envelope of pig erythrocyte and egg phosphattidylcholine vesicles were measured by NMR spectroscopy employing the spin-echo method and nuclear T1 relaxation. The following permeability coefficients (P) and corresponding enthalpies of activation (delta H not equal to ) were determined for glycerol at 25 degree C: for phosphatidylcholine vesicles 5 . 10-6 cm/s and 11 +/- 2 kcal/mol; for pig erythrocytes 7 . 10-8 cm/s and 18 +/- 3 kcal/mol, respectively; for the cytoplasmic membrane of D. salina the permeability at 17 degrees C was found to be exceptionally low and only a lower limit (P less than 5 . 10-11 cm/s) could be calculated. At temperatures above 50 degree C a change in membrane permeability occurred leading to rapid leakage of glycerol accompanied by cell death. The data reinforce the notion that the cytoplasmic membrane of Dunaliella represents a genuine anomaly in its exceptional low permeability to glycerol.
采用自旋回波法和核 T1 弛豫，通过核磁共振光谱测定了甘油在盐生杜氏藻细胞质细胞膜、猪红细胞细胞膜和卵磷脂酰胆碱囊泡中的扩散渗透率。在 25℃下测定了甘油的下列渗透系数（P）和相应的活化焓（ΔH≠）：对于磷脂酰胆碱囊泡，为 5×10⁻⁶ cm/s 和 11±2 kcal/mol；对于猪红细胞，分别为 7×10⁻⁸ cm/s 和 18±3 kcal/mol；对于盐生杜氏藻的细胞质膜，发现在 17℃时渗透率极低，只能计算出下限（P＜5×10⁻¹¹ cm/s）。在高于 50℃的温度下，膜渗透率发生变化，导致甘油快速泄漏并伴随细胞死亡。这些数据强化了这样一种观点，即盐生杜氏藻的细胞质膜对甘油的渗透率极低，是一种真正的异常情况。
