Structure and topography of the membrane-binding C2 domain of factor VIII in the presence of dodecylphosphocholine micelles.
Structure and topography of the membrane-binding C2 domain of factor VIII in the presence of dodecylphosphocholine micelles.
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十二烷基磷酸胆碱胶束存在下因子 VIII 膜结合 C2 结构域的结构和形貌。
DOI：
10.1042/bj3320549
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Gilbert,GE
中科院分区：
文献类型：
--
作者：
Veeraraghavan,S;Baleja,JD;Gilbert,GE
来自抗血友病因子VIII的C2结构域的21个残基肽与因子VIII竞争体外膜结合位点。在这里，我们提供的结构和地形的肽在溶液中，十二烷基磷酸胆碱（DPC）胶束，确定using 1H-NMR光谱。该肽呈现两亲性结构，包括延伸的N-末端区域和C-末端螺旋。Ile 6 ~ Arg 18骨架原子叠加在最低能量结构上的平均均方根偏差为0.7±0.2 μ m。而骨干构象是类似的SDS胶束中，Trp 11侧链的方向是显着改变。吲哚环在SDS胶束中几乎平行于肽骨架，而在DPC胶束中垂直于肽骨架。此外，两个组氨酸的pKa值在SDS中相对于DPC改变超过1个pH单位，这将咪唑环定位于界面区域。由自旋标记的磷脂酰胆碱诱导的谱线增宽表明，大多数穿透DPC胶束的氨基酸侧链是疏水性的。因此，肽的长轴平行于胶束表面，α-螺旋的疏水面提供疏水膜相互作用。SDS中Trp 11和N-末端氨基酸残基相对于DPC显示出较大的化学位移变化，表明该区域可能参与膜磷脂的识别，1H-NMR归属、CD谱、一维1H-NMR谱、化学位移分析和核Overhauser效应信息在补充出版物19950184中报道（11页），其已保藏在英国图书馆文献供应中心，Boston Spa，Wetherby，West约克郡LS 23 7 BQ，U.K，可根据Biochem. J.（1997）321，8中所示的条款从其获得副本。
A 21 residue peptide from the C2 domain of the antihaemophilic factor VIII competes with factor VIII for membrane-binding sitesin vitro. Here, we provide the structure and topography of the peptide in solution, on dodecylphosphocholine (DPC) micelles, determined using1H-NMR spectroscopy. The peptide assumes an amphipathic structure comprising an extended N-terminal region and a C-terminal helix. The average root-mean-square deviation is 0.7±0.2 Å for the superimposition of the backbone atoms of Ile6to Arg18on the lowest energy structure. Whereas the backbone conformation is similar to that in SDS micelles, the Trp11side-chain orientation is dramatically changed. The indole ring is nearly parallel to the peptide backbone in SDS micelles but perpendicular in DPC micelles. Further, pKavalues of the two histidines change by more than 1 pH unit in SDS relative to DPC, which localizes the imidazole rings to the interfacial region. Line-broadening induced by spin-labelled phosphatidylcholine shows that most of the amino acid side-chains that penetrate the DPC micelle are hydrophobic. Thus, the long axis of the peptide lies parallel to the micelle surface and the hydrophobic face of the α-helix provides hydrophobic membrane interaction. The large chemical shift changes shown by Trp11and N-terminal amino acid residues in SDS relative to DPC indicate that this region may be involved in membrane phospholipid recognition.1H-NMR assignments, CD spectra, one-dimensional1H-NMR spectra, chemical-shift analysis and nuclear Overhauser effect information are reported in Supplementary Publication SUP 50184 (11 pages), which has been deposited at the British Library Document Supply Centre, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K, from whom copies can be obtained according to the terms indicated in Biochem. J. (1997)321, 8.