Ringe D, Petsko G A, Kerr D E, Ortiz de Montellano P R
Biochemistry. 1984 Jan 3;23(1):2-4. doi: 10.1021/bi00296a001.
X-ray crystallographic studies of myoglobin do not show an entrance or exit path for potential ligands from the surface to the heme cavity. Efforts to locate such a path have so far centered around dynamic calculations. A structure has now been determined that has a clear opening. Phenylhydrazine reacts with myoglobin in such a way that a phenyl group remains bound to the iron atom. The structure of this complex shows that the side chains of His-64(E7), Arg-45-(CD3), and Val-68(E11) have been forced aside to form an open channel to the surface. Although this may not be the only channel to the iron atom, it seems likely that it is an important one.
对肌红蛋白的X射线晶体学研究未显示潜在配体从表面进入或离开血红素腔的路径。迄今为止，寻找此类路径的工作主要集中在动态计算上。现已确定了一种具有明显开口的结构。苯肼与肌红蛋白反应，使得一个苯基仍然与铁原子结合。该复合物的结构表明，组氨酸-64（E7）、精氨酸-45（CD3）和缬氨酸-68（E11）的侧链已被推开，形成了一条通向表面的开放通道。尽管这可能不是通向铁原子的唯一通道，但它似乎很可能是一条重要通道。
