Growth inhibition at the ice prismatic plane induced by a spruce budworm antifreeze protein : a molecular dynamics simulation study
Growth inhibition at the ice prismatic plane induced by a spruce budworm antifreeze protein : a molecular dynamics simulation study
复制标题
云杉芽虫抗冻蛋白诱导的冰棱面生长抑制：分子动力学模拟研究
DOI：
10.1039/c1cp21929d
复制
发表时间：
2011
影响因子：
3.3
通讯作者：
灘浩樹,古川義純
中科院分区：
文献类型：
--
作者：
F. Mikami;K. Matsuda;H. Kataura;Y. Maniwa;灘浩樹,古川義純
采用分子动力学模拟方法研究了云杉芽虫抗冻蛋白在冰棱界面上的生长动力学。两个初始的结合构象的蛋白质在界面上一个能量稳定和其他能量不稳定进行了检查。对于这两种结合构象，周围的蛋白质观察到冰的生长。冰生长的速度急剧下降，观察周围的蛋白质，最初具有能量稳定的结合构象。模拟结果表明，所观察到的冰的生长速率下降是由于吉布斯-汤姆森效应所造成的熔点下降。最初具有能量不稳定的结合构象的蛋白质显著松弛，从而稳定地结合到生长的冰的棱柱平面界面;此后，也观察到冰生长速率的降低。然而，蛋白质在松弛期间接近的结合构象与最初具有能量稳定结合构象的蛋白质不同。因此，模拟表明存在两种结合构象诱导冰的生长速率下降。这一结果可能与云杉芽虫抗冻蛋白在真实的系统中的高活性有关。
A molecular dynamics simulation was conducted to investigate the growth kinetics at the ice prismatic interface to which a spruce budworm antifreeze protein was bound. Two initial binding conformations of the protein at the interface—one energetically stable and the other energetically unstable—were examined. For both binding conformations, the growth of ice was observed around the protein. A sharp decrease in the rate of ice growth was observed around the protein that initially had the energetically stable binding conformation. Simulation results suggest that the observed decrease in the ice growth rate was attributable to melting point depression caused by the Gibbs–Thomson effect. The protein that initially had the energetically unstable binding conformation markedly relaxed so as to stably bind to the prismatic plane interface of the grown ice; thereafter, a decrease in the ice growth rate was observed as well. However, the binding conformation that the protein approached during the relaxation was different from that of the protein that initially had the energetically stable binding conformation. Thus, the simulation indicates the existence of two binding conformations for inducing a decrease in the ice growth rate. The results are possibly related to the hyperactivity of a spruce budworm antifreeze protein in real systems.