Protein structures by spallation neutron crystallography

Abstract

The Protein Crystallography Station at Los Alamos Neutron Science Center is a high-performance beamline that forms the core of a capability for neutron macromolecular structure and function determination. This capability also includes the Macromolecular Neutron Crystallography (MNC) consortium between Los Alamos (LANL) and Lawrence Berkeley National Laboratories for developing computational tools for neutron protein crystallography, a biological deuteration laboratory, the National Stable Isotope Production Facility, and an MNC drug design consortium between LANL and Case Western Reserve University.

Figure 1

The active site in the XN structure of DFPase showing the coordination of the catalytic calcium ion with E21, N175 and key solvent molecules (Blum et al., 2007 ▶). Neutron and X-ray 2F _o − F _c scattering density maps are represented in blue and red, respectively.

Figure 2

The interaction of His 54 with water molecules in the neutron structure of d-xylose isomerase in the absence of substrate with 2F _o − F _c neutron scattering density represented in blue (Katz et al., 2006 ▶).

Figure 3

A schematic representation of the process used for perdeuterating proteins at the BDL at Los Alamos National Laboratory (LANL). A bacterial culture medium, which we designate Altone, is made from the hydrolyzate of algae (e.g. Scenedesmus obliquus) grown in D₂O and used for protein expression in E. coli. Steps represented by framed boxes can be performed robotically at LANL. Steps represented by shaded boxes can be performed either at LANL or the user’s home laboratory.