S. Qian, S.V. Pingali, K. Weiss, V. Urban, H.M. O'Neill, P. Langan
Oak Ridge National Laboratory,
Keywords: neutron scattering, structural biology, SANS, protein, membrane, RNA, DNA
Summary:Structure-function relationships remain a critical theme in understanding many important biological processes regarding energy, disease and other applications. At Oak Ridge National Laboratory, home to two of the most powerful neutron sources for research High Flux Isotope Reactor (HFIR) and Spallation Neutron Source (SNS), we have developed an open-access user instrument, the Bio-SANS. As an instrument dedicated for biological-related research, it applies techniques of small angle neutron scattering (SANS) to a broad range of research topics. The unique advantage of neutron scattering contrast, often naturally occurring between different types of biomolecules such as protein, lipids, RNA/DNA, etc., affords researchers the ability to study structures of individual components in complex biological systems and at a more biologically relevant condition. Furthermore, the high penetration power of neutrons and the lack of radiation damage make SANS well-suited to the study of large, multi-component biological complexes both in situ and in vivo, by using neutron contrast variation techniques in combination with selective deuterium labeling. With the HFIR neutron source, we have developed the Bio-SANS into a high flux and low experimental background tool versatile for different biological research areas. In addition, a Bio-Deuteration Laboratory is also available to assist and train users in the preparation of deuterium-labeled biomolecules, which allows researchers to take full advantage of neutron scattering. Here we will present a few examples of SANS studies on protein structures in solution and in membrane mimetic environments, a protein-RNA complex, membrane active antibiotic-lipid interactions and hierarchical structures during the biofuel pretreatment.