Recent Developments at the Center for Structural Molecular Biology at Oak Ridge National Laboratory
Authors:
Hugh O’Neill* ([email protected], PI), Sai Venkatesh Pingali, Wellington Leite, Kevin Weiss, Hong-Hai Zhang, Qiu Zhang, Felicia Gilliland, Volker Urban
Institutions:
Oak Ridge National Laboratory
URLs:
Goals
The Center for Structural Molecular Biology (CSMB) at Oak Ridge National Laboratory (ORNL) is funded to support and develop the user access and science research program of the Biological Small-Angle Neutron Scattering (Bio-SANS) instrument at the High Flux Isotope Reactor (HFIR). Bio-SANS is dedicated to the analysis of the structure, function, and dynamics of complex biological systems. The CSMB also operates a Bio-Deuteration Laboratory (BDL) for expression and purification of deuterium labeled biomacromolecules and for synthesis of small molecules and ligands in support of the biology neutron scattering program. The CSMB supports a vibrant biological research community from academia, industry, and government laboratories.
Abstract
The Bio-SANS instrument is ideally suited for studies of biomacromolecules including proteins, DNA/RNA, lipid membranes and other hierarchical complexes. The Bio-SANS detector system is designed to allow simultaneous access to a wide spatial range that enables utilization of the full potential of the high neutron flux from the ORNL HFIR cold source. This team has recently completed the next development stage of the detector system by installation and commissioning of a mid-range detector to complement the existing main and wing detectors. This development will improve data quality for hierarchical systems, decrease Q-resolution mismatch, increase angular coverage, and enable sub-minute time resolution.
Sample environment (SE) capabilities that can accommodate sample types ranging from biomacromolecules in solution to biomass are critically important to realize the full potential of Bio-SANS. One recent SE development effort was to upgrade the robotic sample changer originally installed in 2019 with a Universal Robot (UR5), which has an expanded a temperature-controlled holding area for up to 66 sample cells. A Peltier heating block at the sample position allows rapid temperature change between 10 to 100°C. New science opportunities include in situ kinetic processes of complex biological systems using time-resolved SANS with simultaneous access to multiple length scales. Further development is underway to expand this capability to allow liquid handling at Bio-SANS for mixing samples directly before measurement. Another example is chromatography—SANS for in beam fractionation of biomacromolecules that can operate in continuous flow mode as well as fractionation of complex mixtures of biomacromolecules. The flow cell design accommodates four cells to minimize down time during sequential purifications of multiple proteins.
To broaden the impact of the CSMB and catalyze the synergy between BER program–funded structural biology resources, the team established collaborative programs with the National Synchrotron Light Source II for joint access to SANS and SAXS and with the BER Facilities Integrating Collaborations for User Science (FICUS) program between the DOE Joint Genome Institute at Lawrence Berkeley National Laboratory and the Environmental Molecular Sciences Laboratory at Pacific Northwest National Laboratory.