Direct Evidence That the Proton Motive Force Inhibits Membrane Translocation of Positively Charged Residues within Membrane Proteins*
Direct Evidence That the Proton Motive Force Inhibits Membrane Translocation of Positively Charged Residues within Membrane Proteins*
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质子动力抑制膜蛋白内带正电残基的膜易位的直接证据*
DOI：
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发表时间：
1999
影响因子：
4.8
通讯作者：
R. Dalbey
中科院分区：
文献类型：
--
作者：
Tracy A. Schuenemann;Vondolee M. Delgado;R. Dalbey
M13噬菌体前外壳蛋白需要其信号序列和其膜锚序列两者在蛋白质的成熟部分中用于膜插入。其短的酸性周质环的易位是由质子动力（pmf）刺激的，不需要Sec组分。我们现在发现，当信号或膜锚的疏水性逐渐降低时，pmf对于前被膜内带负电荷残基的移位变得越来越重要。相反，我们发现当pmf含有一个或两个带正电荷的残基时，它会抑制周质环的易位。当插入的前外壳蛋白的疏水性受损时，pmf的这种抑制作用更强。没有观察到pmf效应的不带电的周质环易位，即使当疏水性降低。我们还表明，pmf的Δ λ组分是插入代表性构建体所必需和充分的，并且带电残基的易位效应主要是由于pmf的Δ λ组分而不是pH组分。
The M13 phage procoat protein requires both its signal sequence and its membrane anchor sequence in the mature part of the protein for membrane insertion. Translocation of its short acidic periplasmic loop is stimulated by the proton motive force (pmf) and does not require the Sec components. We now find that the pmf becomes increasingly important for the translocation of negatively charged residues within procoat when the hydrophobicity of the signal or membrane anchor is incrementally reduced. In contrast, we find that the pmf inhibits translocation of the periplasmic loop when it contains one or two positively charged residues. This inhibitory effect of the pmf is stronger when the hydrophobicity of the inserting procoat protein is compromised. No pmf effect is observed for translocation of an uncharged periplasmic loop even when the hydrophobicity is reduced. We also show that the ΔΨ component of the pmf is necessary and sufficient for insertion of representative constructs and that the translocation effects of charged residues are primarily due to the ΔΨ component of the pmf and not the pH component.
影响因子：
3.4
作者：
FLEWELLING, RF;HUBBELL, WL
通讯作者：
HUBBELL, WL
DOI：
10.1016/s0021-9258(19)61980-0
发表时间：
1994-11
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
E. Lee;C. Manoil
通讯作者：
E. Lee;C. Manoil
DOI：
10.1146/annurev.bb.15.060186.001115
发表时间：
1986
期刊：
Annual review of biophysics and biophysical chemistry
影响因子：
--
作者：
B. Honig;W. Hubbell;R. Flewelling
通讯作者：
B. Honig;W. Hubbell;R. Flewelling