STRUCTURAL CHARACTERIZATION OF A 39-RESIDUE SYNTHETIC PEPTIDE CONTAINING THE 2 ZINC-BINDING DOMAINS FROM THE HIV-1 P7-NUCLEOCAPSID PROTEIN BY CD AND NMR-SPECTROSCOPY
STRUCTURAL CHARACTERIZATION OF A 39-RESIDUE SYNTHETIC PEPTIDE CONTAINING THE 2 ZINC-BINDING DOMAINS FROM THE HIV-1 P7-NUCLEOCAPSID PROTEIN BY CD AND NMR-SPECTROSCOPY
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DOI：
10.1016/0014-5793(91)80825-n
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发表时间：
1991-11-04
期刊：
影响因子：
3.5
通讯作者：
GRONENBORN, AM
中科院分区：
文献类型：
--
作者：
OMICHINSKI, JG;CLORE, GM;GRONENBORN, AM
采用固相法合成了含有p7核衣壳蛋白两个锌结合区的39个残基的多肽(p7-df)。在锌离子存在和不存在的情况下，用圆二色谱和核磁共振光谱对多肽的溶液结构进行了表征。圆二色谱表明，该多肽在无锌条件下呈无规卷曲构象，在有锌条件下呈有序结构。二维核磁共振谱表明，当每当量的多肽中加入2当量的氯化锌时，多肽中的两个锌结合结构域形成稳定但独立的单位。基于核Overhauser(NOE)数据的结构计算表明，在坐标误差范围内，两个锌结合结构域具有相同的多肽折叠(主链原子、锌原子以及配位的半胱氨酸和组氨酸配体约为0.5埃)。连接区(Arg17-Gly23)的特点是序列NOE的数量非常有限，并且没有任何非序列NOE的存在表明多肽链的这一区域是高度灵活的。后者与大量碱性残基的出现相结合(连接区中七分之四的残基表明它可能用于允许核酸识别序列在蛋白质内的适应性定位。
A 39-residue peptide (p7-DF) containing the two zinc binding domains of the p7 nucleocapsid protein was prepared by solid-phase peptide synthesis. The solution structure of the peptide was characterized using circular dichroic and nuclear magnetic resonance spectroscopy in both the presence and absence of zinc ions. Circular dichroic spectroscopy indicates that the peptide exhibits a random coil conformation in the absence of zinc but appears to form an ordered structure in the presence of zinc. Two-dimensional nuclear magnetic resonance spectroscopy indicates that the two zinc binding domains within the peptide form stable, but independent, units upon the addition of 2 equivalents of ZnCl2 per equivalent of peptide. Structure calculations on the basis of nuclear Overhauser (NOE) data indicate that the two zinc binding domains have the same polypeptide fold within the errors of the coordinates (approximately 0.5 angstrom for the backbone atoms, the zinc atoms and the coordinating cysteine and histidine ligands). The linker region (Arg17-Gly23) is characterized by a very limited number of sequential NOEs and the absence of any non-sequential NOEs suggest that this region of the polypeptide chain is highly flexible. The latter coupled with the occurrence of a large number of basic residues (four out of seven in the linker region suggests that it may serve to allow adaptable positioning of the nucleic acid recognition sequences within the protein.