Dalgarno D C, Harding M W, Lazarides A, Handschumacher R E, Armitage I M
Biochemistry. 1986 Nov 4;25(22):6778-84. doi: 10.1021/bi00370a008.
High-field 1H NMR spectroscopy has been used to study the conformation of the cytosolic cyclosporin A binding protein cyclophilin. For the drug-free form of cyclophilin, spectral editing methods in conjunction with a pH titration were used to identify all four His residues present in the protein, and two-dimensional COSY and RELAY spectroscopy was used to elucidate the scalar connectivities in the aromatic and upfield methyl regions of the spectrum. From these scalar connectivities, it was possible to distinguish between inter- and intraresidue dipolar interactions within the aromatic and upfield methyl regions of cyclophilin in the NOESY spectrum. The results of this analysis showed extensive interresidue cross-relaxation among and between these latter spectral regions indicative of the proximal relationships of several of these residues and the presence of a hydrophobic core within cyclophilin.
高场¹H核磁共振光谱已被用于研究胞质环孢菌素A结合蛋白亲环蛋白的构象。对于无药物形式的亲环蛋白，采用光谱编辑方法结合pH滴定来鉴定蛋白质中存在的所有四个组氨酸残基，并使用二维COSY和RELAY光谱来阐明光谱中芳香族和高场甲基区域的标量连接性。根据这些标量连接性，可以在NOESY光谱中区分亲环蛋白芳香族和高场甲基区域内的残基间和残基内偶极相互作用。该分析结果表明，这些后光谱区域之间以及它们之间存在广泛的残基间交叉弛豫，这表明其中几个残基存在近端关系，并且亲环蛋白内存在疏水核心。
