ジャーナル: J Struct Biol / 年: 2010 タイトル: The random-model method enables ab initio 3D reconstruction of asymmetric particles and determination of particle symmetry. 著者: Eduardo Sanz-García / Aaron B Stewart / David M Belnap / 要旨: Model-based, 3D reconstruction techniques depend on reliable starting models. We present an extension of the random-model method (RMM) that allows the ab initio generation of suitable starting models ...Model-based, 3D reconstruction techniques depend on reliable starting models. We present an extension of the random-model method (RMM) that allows the ab initio generation of suitable starting models directly from un-averaged, experimental images of asymmetric or symmetric particles. Therefore, the asymmetric RMM can also be used to determine point-group symmetry. The procedure is facilitated by the use of (a) variable angular step-sizes during iterative origin and orientation searches, (b) high numbers of particle images, and (c) highly defocused images. The method is inhibited by mixed-handedness orientation assignments and by particles with inconspicuous features. For symmetric particles, symmetric RMMs can overcome these deficiencies.
アルゴリズム: OTHER / 解像度のタイプ: BY AUTHOR / 解像度: 35.0 Å / 解像度の算出法: FSC 0.5 CUT-OFF / ソフトウェア - 名称: PFT3DR, Bsoft 詳細: Random-model method. Angular step-size was initially set to 20 deg. in the first iteration and gradually decreased by 0.19 deg. in each successive iteration, until a lower limit of 1 deg. was reached. 使用した粒子像数: 4198