Small-angle X-ray scattering from RNA, proteins, and protein complexes.
Small-angle X-ray scattering (SAXS) is increasingly used to characterize the structure and interactions of biological macromolecules and their complexes in solution. Although still a low-resolution technique, the advent of high-flux synchrotron sources and the development of algorithms for the reconstruction of 3-D electron density maps from 1-D scattering profiles have made possible the generation of useful low-resolution molecular models from SAXS data. Furthermore, SAXS is well suited for the study of unfolded or partially folded conformational ensembles as a function of time or solution conditions. Here, we review recently developed algorithms for 3-D structure modeling and applications to protein complexes. Furthermore, we discuss the emerging use of SAXS as a tool to study membrane protein-detergent complexes. SAXS is proving useful to study the folding of functional RNA molecules, and finally we discuss uses of SAXS to study ensembles of denatured proteins.
Lipfert
Jan
J
Department of Physics, Biophysics Program, Stanford University, Stanford, California 94305, USA. lipfert@stanford.edu
Doniach
Sebastian
S
D000818:Animals; D001703:Biophysics / Q000379:methods*; D003902:Detergents / Q000737:chemistry; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D008968:Molecular Conformation; D017785:Photons; D011489:Protein Denaturation; D017510:Protein Folding; D011506:Proteins / Q000737:chemistry*; D012313:RNA / Q000737:chemistry*; D012542:Scattering, Radiation; D014965:X-Rays
D003902:Detergents; D008823:Micelles; D011506:Proteins; D012313:RNA