论文标题
无分子的分子动力学:搜索具有生成神经网络的蛋白质的构象空间
Molecular dynamics without molecules: searching the conformational space of proteins with generative neural networks
论文作者
论文摘要
全原子和粗粒分子动力学是两个广泛使用的计算工具,用于研究蛋白质的构象状态。然而,这两种仿真方法遭受了这样的事实,即在没有获得超级计算资源的情况下,这些状态可检测到的时间和长度尺度很难实现。这种方法的一种替代方法是基于编码分子动力学的原子轨迹作为没有物理粒子的速记版本,然后学习通过使用人工智能来传播编码的轨迹。在这里,我们表明,作为Ramachandran盆地类的向量,分子动力学轨迹框架的简单文本表示保留了蛋白质在每个框架中的完整原子化表示的大多数结构信息,并且可用于生成等效的无原子轨迹,适用于适合训练不同类型的生成性神经网络。反过来,训练有素的生成模型可用于无限期地扩展无原子动力学,或从其在潜在的模型中从其表示中采样蛋白质的构象空间。我们将这种方法定义为没有分子的分子动力学,并表明它可以涵盖与传统分子动力学难以访问的蛋白质的物理相关状态。
All-atom and coarse-grained molecular dynamics are two widely used computational tools to study the conformational states of proteins. Yet, these two simulation methods suffer from the fact that without access to supercomputing resources, the time and length scales at which these states become detectable are difficult to achieve. One alternative to such methods is based on encoding the atomistic trajectory of molecular dynamics as a shorthand version devoid of physical particles, and then learning to propagate the encoded trajectory through the use of artificial intelligence. Here we show that a simple textual representation of the frames of molecular dynamics trajectories as vectors of Ramachandran basin classes retains most of the structural information of the full atomistic representation of a protein in each frame, and can be used to generate equivalent atom-less trajectories suitable to train different types of generative neural networks. In turn, the trained generative models can be used to extend indefinitely the atom-less dynamics or to sample the conformational space of proteins from their representation in the models latent space. We define intuitively this methodology as molecular dynamics without molecules, and show that it enables to cover physically relevant states of proteins that are difficult to access with traditional molecular dynamics.