STUDY OF SPIN LABELED WALP PEPTIDES

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 我们开始使用WALP和KALP肽研究脂质-蛋白质相互作用。这些α-螺旋跨膜肽，具有不同长度的亮氨酸和丙氨酸的疏水序列，在两端侧接两个作为膜锚定物的色氨酸或赖氨酸。WALP：Ac-GWW（LA）nLWWA，例如对于WALP 23 n=8，以及KALP：Ac-GKK（LA）nLKKA。这些肽，不像我们小组以前研究的天然肽，可以合成各种α-螺旋长度。这将使我们能够系统地研究肽长度和脂质双层厚度之间的疏水性错配的作用。从疏水匹配/错配的角度研究脂质-蛋白质相互作用是我们小组熟悉的方法;例如，参见我们对短杆菌肽A在各种脂质相中的研究。在相同的脂质相中使用几种具有不同α-螺旋长度的肽将允许我们将疏水错配的特定效应与脂质环境的效应分开。我们的主要兴趣是疏水性错配对模型膜中螺旋倾斜和聚集数WALP/KALP肽的影响。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We started studying lipid-protein interactions using WALP and KALP peptides. These alpha-helical transmembrane peptides, with a hydrophobic sequence of leucine and alanine of varying length, are flanked at both ends by two tryptophans or lysines as membrane anchors. WALP: Ac-GWW(LA)nLWWA, for example for WALP23 n=8, and KALP: Ac-GKK(LA)nLKKA. These peptides, unlike natural peptides previously studied in our group, can be synthesized in a variety of alpha-helical lengths. It will allow us to engage in a systematic study of the role of hydrophobic mismatch between the peptide length and the lipid bilayer thickness. Studying lipid-protein interactions from the standpoint of hydrophobic matching/mismatching is a familiar approach for our group; see for example our study of Gramicidin A in a variety of lipid phases. Use of several of peptides with different alpha-helical length in the same lipid phase will allow us to separate specific effects of hydrophobic mismatch from effects of lipid environment, in general. Our primary interest is the effect of hydrophobic mismatch on helical tilt and aggregation number WALP/KALP peptides in model membranes.