Internal packing of helical membrane proteins
Internal packing of helical membrane proteins
复制标题
DOI：
10.1073/pnas.97.11.5796
复制
发表时间：
2000-05-23
影响因子：
11.1
通讯作者：
Fleming, PJ
中科院分区：
文献类型：
--
作者：
Eilers, M;Shekar, SC;Fleming, PJ
螺旋堆积在膜蛋白的折叠、稳定和结合中起重要作用，对7个完整膜蛋白和37个可溶性蛋白质螺旋部分的堆积分析表明，膜蛋白的螺旋堆积数值(0.431)高于可溶性蛋白质的堆积数值(0.405)，整体膜蛋白中最高的堆积数值来自小疏水氨基酸(G和A)和小羟基氨基酸(S和T)，而在可溶性蛋白质中，大疏水和芳香族残基的堆积数值最高，膜蛋白在跨膜螺旋-螺旋界面的堆积数值最高。甘氨酸和丙氨酸是膜蛋白中埋藏氨基酸中出现频率最高的，而亮氨酸和丙氨酸是可溶性蛋白中最常见的埋藏残基，这与膜蛋白中螺旋之间的轴向间隔较短是一致的。分析中揭示的紧密螺旋堆积有助于膜蛋白的稳定性，并可能弥补作为膜中螺旋-螺旋结合驱动力的疏水效应的缺乏。
Helix packing is important in the folding, stability, and association of membrane proteins, Packing analysis of the helical portions of 7 integral membrane proteins and 37 soluble proteins show that the helices in membrane proteins have higher packing values (0.431) than in soluble proteins (0.405), The highest packing values in integral membrane proteins originate from small hydrophobic (G and A) and small hydroxyl-containing (S and T) amino acids, whereas in soluble proteins large hydrophobic and aromatic residues have the highest packing values, The highest packing values for membrane proteins are found in the transmembrane helix-helix interfaces. Glycine and alanine have the highest occurrence among the buried amino acids in membrane proteins, whereas leucine and alanine are the most common buried residue in soluble proteins, These observations are consistent with a shorter axial separation between helices in membrane proteins. The tight helix packing revealed in this analysis contributes to membrane protein stability and likely compensates for the lack of the hydrophobic effect as a driving force for helix-helix association in membranes.