title: Anomalous difference signal in protein crystals.
abstract: A scattering-angle-dependent formula is obtained for estimation of anomalous diffraction signals in Friedel pairs in protein crystals. In addition to the angle dependences of atomic form factor and temperature factor, a correlation form factor is introduced for the first time to take into account anomalous-scattering clusters such as disulfide bonds. Good agreements with experimental observations suggest that such correlated anomalous difference signals may be visible from measurements before a complete structural solution is obtained.
authors.affiliation: Cornell High Energy Synchrotron Source (CHESS), Wilson Laboratory, Cornell University, Ithaca, NY 14853, USA. qs11@cornell.edu
authors.forename: Qun
authors.initials: Q
authors.lastname: Shen
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Steven E
authors.initials: SE
authors.lastname: Ealick
mesh_terms: D003460:Crystallization; D008962:Models, Theoretical; D011506:Proteins / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods*
chemical_list: D011506:Proteins