Islam Tunazzina, Poteat Michael, He Jing
Department of Computer Science, Old Dominion University, Norfolk, VA 23529.
ACM BCB. 2017 Aug;2017:650-654.
Electron cryo-microscopy (Cryo-EM) technique produces density maps that are 3-dimensional (3D) images of molecules. It is challenging to derive atomic structures of proteins from 3D images of medium resolutions. Twist of a β-strand has been studied extensively while little of the known information has been directly obtained from the 3D image of a β-sheet. We describe a method to characterize the twist of β-strands from the 3D image of a protein. An analysis of 11 β-sheet images shows that the Averaged Minimum Twist (AMT) angle is larger for a close set than for a far set of β-traces.
电子冷冻显微镜（Cryo-EM）技术可生成分子的三维（3D）图像密度图。从中等分辨率的3D图像推导蛋白质的原子结构具有挑战性。β-链的扭曲已得到广泛研究，而很少有已知信息是直接从β-折叠的3D图像中获得的。我们描述了一种从蛋白质的3D图像中表征β-链扭曲的方法。对11个β-折叠图像的分析表明，β-链迹线紧密组的平均最小扭曲（AMT）角大于远组的平均最小扭曲角。
