肌红蛋白力致去折叠的全原子分析

位于脊椎动物骨骼肌中的肌红蛋白在生命过程中扮演着重要角色,其折叠过程依赖于血红素的绑定.本文着重于肌红蛋白在力的作用下去折叠过程的全原子统计分析.结果表明血红素不仅具有生物学上的功能,而且决定其去折叠的动力学过程.在血红素不存在的情况下,肌红蛋白的力致去折叠过程存在一个中间态,其构象不同于化学变性剂所导致的去折叠中间态,发现新的中间态.结论与相关实验结果相符,揭示了肌红蛋白力致去折叠的一般机制.

Atomistic Analysis of Myoglobin Mechanical Unfolding

Myoglobin, which exists widely in skeletal muscle of vertebrates, plays crucial roles in life processes. Its proper folding depends on the binding of heme. In this paper, we report an atomistic and statistical analysis of force-induced unfolding of myoglobin with and without heme binding. It shows that heme is responsible for not only its biological functions, but also its unfolding dynamics. The unfolding pathway of myoglobin without heme binding involve an intermediate configuration. More importantly, it shows that intermediate state in force-induced unfolding process is different from that in chemical denaturant, which leads to the discovery of new intermediate configurations. Our results are in good agreement with related experimental observations and provide significant insight into general mechanisms of myoglobin unfolding.