Meunier B, Colson A M, Rich P R
Glynn Research Institute, Bodmin, Cornwall, UK.
Biochim Biophys Acta. 1995 Nov 15;1253(1):13-5. doi: 10.1016/0167-4838(95)92373-4.
Second-site revertants were selected from a respiratory-deficient mutant carrying the mutation D369N located in a loop between helices IX and X close to H376 and H378, the proposed ligands of haem a3 and haem a, respectively. A reversion was observed in subunit II, in the vicinity of the CuA ligands. This same reversion compensates the subunit I deficiency mutation, S140L, assumed to be near H62, the second putative histidine ligand to haem a. These data enable us to propose a three-dimensional topology in which CuA in subunit II is located on top of the Positive-side of subunit I and in proximity to all three of its metal centres.
从一个呼吸缺陷型突变体中筛选出二次位点回复突变体，该突变体携带位于螺旋IX和X之间的环中的D369N突变，靠近分别为血红素a3和血红素a的假定配体H376和H378。在亚基II中靠近CuA配体的位置观察到了回复突变。同样的回复突变补偿了亚基I的缺陷突变S140L，该突变假定靠近H62，H62是血红素a的第二个假定组氨酸配体。这些数据使我们能够提出一种三维拓扑结构，其中亚基II中的CuA位于亚基I的正极侧顶部，并且靠近其所有三个金属中心。
