Im W B, Ling K Y, Faust R G
J Membr Biol. 1982;65(1-2):131-7. doi: 10.1007/BF01870476.
A membrane extract enriched with the Na+ -dependent D-glucose transport system was obtained by differential cholate solubilization of rat renal brush border membranes in the presence of 120 mM Na+ ions. Sodium ions were essential in stabilizing the transport system during cholate treatment. This membrane extract was further purified with respect to its Na+-coupled D-glucose transport activity and protein content by the use of asolectin-equilibrated hydroxylapatite. The reconstituted proteoliposomes prepared from this purified fraction showed a transient accumulation of D-glucose in response to a Na+ gradient. The observed rate of Na+-coupled D-glucose uptake by the proteoliposomes represented about a sevenfold increase as compared to that of the reconstituted system derived from an initial 1.2% cholate extract of the membranes. Other Na+-coupled transport systems such as L-alanine, alpha -ketoglutarate and phosphate were not detected in these reconstituted proteoliposomes.
在120 mM钠离子存在的情况下，通过对大鼠肾刷状缘膜进行差示胆酸盐增溶，获得了富含钠离子依赖性D - 葡萄糖转运系统的膜提取物。在胆酸盐处理过程中，钠离子对于稳定转运系统至关重要。利用大豆卵磷脂平衡的羟基磷灰石，根据其钠离子偶联的D - 葡萄糖转运活性和蛋白质含量，对该膜提取物进一步纯化。由该纯化级分制备的重组蛋白脂质体显示，响应钠离子梯度，D - 葡萄糖出现瞬时积累。与源自膜的初始1.2%胆酸盐提取物的重组系统相比，观察到蛋白脂质体对钠离子偶联的D - 葡萄糖摄取速率增加了约7倍。在这些重组蛋白脂质体中未检测到其他钠离子偶联转运系统，如L - 丙氨酸、α - 酮戊二酸和磷酸盐。
