Structural studies on apolipoprotein B: controllable heterogeneity of the complex formed with the surfactant, Triton X-100.
Structural studies on apolipoprotein B: controllable heterogeneity of the complex formed with the surfactant, Triton X-100.
复制标题
载脂蛋白 B 的结构研究：与表面活性剂 Triton X-100 形成的复合物的可控异质性。
作者：
B. Patterson;L. L. Kilgore;P. Chun;W. Fisher
与 Triton X-100 (T-ApoB) 复合的载脂蛋白 B 已从人类低密度脂蛋白 (LDL) 中分离出来。通过沉降速度分析时，制剂是异质的，存在主要的 12 S 物质和次要的 17 S 物质。 12ST-ApoB复合物的分子量为880,000，含有400,000道尔顿的蛋白质。该复合物的流体动力学测量结果与轴比为 13:1、结合水为 0.22 g/g 的长椭球模型一致。异质性是由于 12 S 复合物不可逆地聚集成离散的 17 S 和更快的沉积成分而产生的。一个重要的发现是，可以阐明和控制这种 T-apoB 异质性的三个决定因素。首先，聚集的初始状态主要受Triton和LDL混合技术的影响。其次，一旦分离，T-ApoB 复合物会缓慢但自发地在 4°C 下进一步聚集；随着温度的升高，聚集的速率和程度显着增强。最后，展开并暴露蛋白质结构的试剂（高氯酸盐、硫氰酸盐和还原剂）会导致聚集增加。控制异质性的能力对于有关 apoB 与表面活性剂和脂质相互作用的其他研究具有重要意义。
Apolipoprotein B complexed with Triton X-100 (T-ApoB) has been isolated from human low density lipoprotein (LDL). Preparations are heterogeneous when analyzed by sedimentation velocity, with a major 12 S species and minor 17 S species present. The 12 S T-ApoB complex possesses a molecular weight of 880,000 containing 400,000 daltons of protein. Hydrodynamic measurements on this complex are consistent with a prolate ellipsoid model having an axial ratio of 13:1 and 0.22 g/g of bound water. Heterogeneity results from the irreversible aggregation of 12 S complexes into discrete 17 S and faster sedimenting components. A significant finding is that three determinants of this T-apoB heterogeneity could be elucidated and controlled. First, the initial state of aggregation is mainly influenced by the technique by which Triton and LDL are mixed. Second, once isolated, T-ApoB complexes slowly but spontaneously undergo further aggregation at 4 degrees C; the rate and extent of aggregation is enhanced remarkably with increasing temperature. Finally, reagents that unfold and expose protein structure (perchlorate, thiocyanate, and reducing reagents) lead to increased aggregation. The ability to control heterogeneity carries important implications for other studies concerning interactions of apoB with surfactants and lipids.
人血浆载脂蛋白 B 的巯基化学和溶解度特性。
影响因子：
2.9
作者：
Cardin,AD;Witt,KR;Barnhart,CL;Jackson,RL
通讯作者：
Jackson,RL