Hydrophobic content and lipid interactions of wild-type and mutant OmpA signal peptides correlate with their in vivo function.
Hydrophobic content and lipid interactions of wild-type and mutant OmpA signal peptides correlate with their in vivo function.
复制标题
野生型和突变型 OmpA 信号肽的疏水含量和脂质相互作用与其体内功能相关。
DOI：
10.1021/bi00106a012
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发表时间：
1991
期刊：
影响因子：
2.9
通讯作者：
Gierasch,LM
中科院分区：
文献类型：
--
作者：
Hoyt,DW;Gierasch,LM
德克萨斯大学西南医学中心生物化学和药理学系，达拉斯，德克萨斯州 75235-9041 收稿日期：1991 年 6 月 11 日；修订稿于 1991 年 8 月 5 日收到摘要：与大肠杆菌外膜蛋白 OmpA 和几个突变体的野生型信号序列相对应的肽已被合成并进行了生物物理表征。这些突变是与井上及其同事合作设计的，以测试对其功能所需的信号序列关键特征的理解。这些突变体的体内结果已被报道[Lehnhardt, S., Pollitt, S., & Inouye, M.(1987) J. Biol.化学。 262、1716-1719； Goldstein, J.、Lehnhardt, S. 和 Inouye, M.(1990) J. Bacteriol。 172、1225-1231； Goldstein, J.、Lehnhardt, S. 和 Inouye, M.(1991) J. Biol。化学。 266, 14413-14417]，本文比较了六种 OmpA 信号肽的构象和膜相互作用特性。与体内功能性 OmpA 信号序列相对应的肽在膜模拟环境中主要呈螺旋状，并且容易插入磷脂双层中。非功能性 OmpA 信号肽可能具有高螺旋含量，但不会深入渗透到双层的酰基链区域。信号肽插入膜的能力及其体内功能与其疏水核心的残基平均疏水性相关。 OmpA 信号肽获得的结果与我们之前对对应于 LamB 信号序列和突变体的肽的观察结果非常相似，认为信号序列的关键生物物理特性是普遍的，尽管它们缺乏一级序列同一性。尽管为了阐明蛋白质输出中信号序列的作用付出了相当大的努力[评论参见 Gierasch (1989), Randall et al.(1987), Benson et al.(1985), Gennity
Departments of Biochemistry and Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75235-9041 Received June 11, 1991; Revised Manuscript Received August 5, 1991 abstract: Peptides corresponding to the wild-type signal sequence of the Escherichia coli outer membrane protein OmpA and several mutants have been synthesized and characterized biophysically. The mutations were designed collaboratively with Inouye and co-workers to test the understanding of the critical char-acteristics of signal sequences required for their functions. The in vivo results for these mutants have been reported [Lehnhardt, S., Pollitt, S., & Inouye, M.(1987) J. Biol. Chem. 262, 1716-1719; Goldstein, J., Lehnhardt, S., & Inouye, M.(1990) J. Bacteriol. 172, 1225-1231; Goldstein, J., Lehnhardt, S., & Inouye, M.(1991) J. Biol. Chem. 266, 14413-14417], and the present paper compares the conformational and membrane-interactive properties of six of the OmpA signal peptides. Peptides corresponding to functional OmpA signal sequences in vivo are predominantly-helical in membrane-mimetic environments and insert readily into phospholipid bilayers. Nonfunctional OmpA signalpeptides may have high helical content but do not penetrate deeply into the acyl chain region of bilayers. The ability of the signal peptides to insert into membranesand their in vivo function correlate with the residue-average hydrophobicity of their hydrophobic cores. The results obtained on OmpA signal peptides parallel closely our previous observations on peptides corresponding to the LamB signal sequence andmutants, arguing that the critical biophysical properties of signal sequences are general despite their lack of primary sequence identity. espite considerable effort directed at elucidating theroles of signal sequences in protein export [for reviews see Gierasch (1989), Randall et al.(1987), Benson et al.(1985), Gennity