Sopkova-De Oliveira Santos J, Vincent M, Tabaries S, Chevalier A, Kerboeuf D, Russo-Marie F, Lewit-Bentley A, Gallay J
UFR des Sciences Pharmaceutiques, 5 rue Vaubenard, F-14032 Caen, France.
FEBS Lett. 2001 Mar 30;493(2-3):122-8. doi: 10.1016/s0014-5793(01)02285-2.
The domain III of annexin 5 undergoes a Ca(2+)- and a pH-dependent conformational transition of large amplitude. Modeling of the transition pathway by computer simulations suggested that the interactions between D226 and T229 in the IIID-IIIE loop on the one hand and the H-bond interactions between W187 and T224 on the other hand, are important in this process [Sopkova et al. (2000) Biochemistry 39, 14065-14074]. In agreement with the modeling, we demonstrate in this work that the D226K mutation behaves as a molecular switch of the pH- and Ca(2+)-mediated conformational transition. In contrast, the hydrogen bonds between W187 and T224 seem marginal.
膜联蛋白5的结构域III经历了大幅度的Ca(2+)和pH依赖性构象转变。通过计算机模拟对转变途径进行建模表明，一方面IIID-IIIE环中D226与T229之间的相互作用，另一方面W187与T224之间的氢键相互作用，在这一过程中很重要 [索普科娃等人（2000年）《生物化学》39卷，第14065 - 14074页]。与建模结果一致，我们在这项工作中证明，D226K突变表现为pH和Ca(2+)介导的构象转变的分子开关。相比之下，W187与T224之间的氢键似乎作用不大。
