Mayo K H, Schaudies P, Savage C R, De Marco A, Kaptein R
Biochem J. 1986 Oct 1;239(1):13-8. doi: 10.1042/bj2390013.
Aromatic amino acid residues in epidermal growth factor (EGF) isolated from the rat have been investigated by proton n.m.r. and nuclear Overhauser methods at 500 MHz and by photochemically induced dynamic nuclear polarization (photo-c.i.d.n.p.) experiments at 360 MHz. Rat EGF contains six aromatic residues, i.e. one histidine and five tyrosine residues. pH titration data allow identification of the histidine imidazole ring protons, whereas two-dimensional n.m.r. correlated spectroscopy establishes connectivities between tyrosine ring (2,6) and (3,5) proton resonances. Photo-c.i.d.n.p. data give evidence for solvent exposure of the one histidine and the five tyrosine residues in rat EGF. Nuclear Overhauser experiments and pH titration data suggest proximity relationships among four of the tyrosine residues and the histidine residue. These data indicate the presence of a clustered, aromatic, structural domain on the protein surface and may provide a clue to the understanding of the functional structure of EGF.
通过500兆赫的质子核磁共振和核Overhauser方法以及360兆赫的光化学诱导动态核极化（光化学诱导动态核极化）实验，对从大鼠中分离出的表皮生长因子（EGF）中的芳香族氨基酸残基进行了研究。大鼠EGF含有六个芳香族残基，即一个组氨酸和五个酪氨酸残基。pH滴定数据可确定组氨酸咪唑环质子，而二维核磁共振相关光谱则确定了酪氨酸环（2,6）和（3,5）质子共振之间的连接关系。光化学诱导动态核极化数据证明了大鼠EGF中一个组氨酸和五个酪氨酸残基暴露于溶剂中。核Overhauser实验和pH滴定数据表明四个酪氨酸残基和组氨酸残基之间存在邻近关系。这些数据表明蛋白质表面存在一个聚集的芳香结构域，可能为理解EGF的功能结构提供线索。
