title: Applications of direct methods in protein crystallography for dealing with diffraction data down to 5 Å resolution.
abstract: Apart from solving the heavy-atom substructure in proteins and ab initio phasing of protein diffraction data at atomic resolution, direct methods have also been successfully combined with other protein crystallographic methods in dealing with diffraction data far below atomic resolution, leading to significantly improved results. In this respect, direct methods provide phase constraints in reciprocal space within a dual-space iterative framework rather than solve the phase problem independently. Applications of this type of direct methods to difficult SAD phasing, model completion and low-resolution phase extension will be described in detail.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
authors.forename: Haifu
authors.initials: H
authors.lastname: Fan
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
authors.forename: Yuanxin
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
authors.forename: Yao
authors.initials: Y
authors.lastname: He
authors.affiliation: Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China.
authors.forename: Zhengjiong
authors.initials: Z
authors.lastname: Lin
authors.affiliation: School of Life Sciences, Tsinghua University, Beijing, 100084, People's Republic of China.
authors.forename: Jiawei
authors.initials: J
authors.lastname: Wang
authors.affiliation: Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, People's Republic of China.
authors.forename: Deqiang
authors.initials: D
authors.lastname: Yao
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
mesh_terms: D000465:Algorithms; D018360:Crystallography, X-Ray / Q000379:methods; D029968:Escherichia coli Proteins / Q000737:chemistry; D026901:Membrane Transport Proteins / Q000737:chemistry; D008958:Models, Molecular
chemical_list: D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; C093118:UraA protein, E coli
keywords: SAD phasing; direct methods; model completion; phase extension; proteins