The control of transmembrane helix transverse position in membranes by hydrophilic residues
The control of transmembrane helix transverse position in membranes by hydrophilic residues
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DOI：
10.1016/j.jmb.2007.10.032
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发表时间：
2007-12-14
影响因子：
5.6
通讯作者：
London, Erwin
中科院分区：
文献类型：
--
作者：
Krishnakumar, Shyarn S.;London, Erwin
在模型膜囊泡中研究了亲水性残基转移双层内跨膜（TM）螺旋横向位置的能力。通过荧光测量疏水序列中心的色氨酸残基的膜深度来检测横向位移。它们也估计从TM跨越序列的有效长度，来自TM配置的稳定性条件下的负疏水性错配。亲水性残基（在第五位的21个残基的疏水序列组成的交替亮氨酸和丙氨酸残基和两侧两端由两个赖氨酸）诱导的横向位移，移动亲水性残基更接近膜表面。在pH 7时，位移程度对亲水残基身份的依赖性按以下顺序增加：
The ability of hydrophilic residues to shift the transverse position of transmembrane (TM) helices within bilayers was studied in model membrane vesicles. Transverse shifts were detected by fluorescence measurements of the membrane depth of a Trp residue at the center of a hydrophobic sequence. They were also estimated from the effective length of the TM-spanning sequence, derived from the stability of the TM configuration under conditions of negative hydrophobic mismatch. Hydrophilic residues (at the fifth position in a 21-residue hydrophobic sequence composed of alternating Leu and Ala residues and flanked on both ends by two Lys) induced transverse shifts that moved the hydrophilic residue closer to the membrane surface. At pH 7, the dependence of the extent of shift upon the identity of the hydrophilic residue increased in the order: L