Flanking aromatic residue competition influences transmembrane peptide helix dynamics
Flanking aromatic residue competition influences transmembrane peptide helix dynamics
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DOI：
10.1002/1873-3468.13926
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发表时间：
2020-09
期刊：
影响因子：
3.5
通讯作者：
M. McKay;D. Greathouse;R. Koeppe
中科院分区：
文献类型：
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作者：
M. McKay;D. Greathouse;R. Koeppe
为了研究支持膜蛋白性质的生物物理原理和脂类相互作用，利用氢谱研究了GW4，20ALP23(乙酰-GGAW4A(LA)6LAW20AGA-酰胺)高动态跨膜螺旋上色氨酸残基邻位的变化。研究发现，L5，19GW4，20ALP23，一个低到中等动态的GW5，19ALP23的序列异构体，保持着高度的动态。相比之下，移除W4以产生F4，5GW20ALP23可以恢复低水平的动态平均，类似于F4，5GW19ALP23螺旋。有趣的是，高水平的动态平均要求色氨酸残基W4和W20都存在于螺旋的相反面上，而不取决于残基5是亮氨酸还是丙氨酸。关于螺旋动态平均和特定残基在磷胆碱膜界面的位置，讨论了螺旋解旋和潜在的齐聚作用。
To address biophysical principles and lipid interactions that underlie the properties of membrane proteins, modifications that vary the neighbors of tryptophan residues in the highly dynamic transmembrane helix of GW4,20ALP23 (acetyl‐GGAW4A(LA)6LAW20AGA‐amide) were examined using deuterium NMR spectroscopy. It was found that L5,19GW4,20ALP23, a sequence isomer of the low to moderately dynamic GW5,19ALP23, remains highly dynamic. By contrast, a removal of W4 to produce F4,5GW20ALP23 restores a low level of dynamic averaging, similar to that of the F4,5GW19ALP23 helix. Interestingly, a high level of dynamic averaging requires the presence of both tryptophan residues W4 and W20, on opposite faces of the helix, and does not depend on whether residue 5 is Leu or Ala. Aspects of helix unwinding and potential oligomerization are discussed with respect to helix dynamic averaging and the locations of particular residues at a phosphocholine membrane interface.