The story “Neutron Diffraction Overcomes Flux Limits to Resolve a Large Protein Structure” (Physics Today, Physics Today 0031-9228 56 11 2003 17 https://doi.org/10.1063/1.1634521 November 2003, page 17 ) captures the excitement that has been generated in the structural biology community by recent results from neutron diffraction studies of large protein structures. As the scientists who built and operate the protein crystallography station (PCS) featured in the report, we felt compelled to write in order to avoid any misunderstanding about the role of the PCS in the development of neutron protein crystallography.
Experiments in the late 1960s led to a neutron protein crystallography program at the reactor run by Brookhaven National Laboratory (BNL); that program provided important insights into the structure and function of a number of proteins. A similar program was started at the Institut Laue–Langevin (ILL) reactor in France in the 1980s, and another in the 1990s at the reactor run by the Japan Atomic Energy Research Institute (JAERI). The BNL reactor experienced frequent shutdowns in the 1990s, including its permanent shutdown in 1996. Those incidents, coupled with the shutdown of the ILL reactor in 1991, terminated neutron protein crystallography in North America and Europe for most of the 1990s.
After the ILL restarted in 1995, a new type of protein crystallography station, the Laue diffractometer (LADI), was built; it uses the Laue method and the detector technology of neutron image plates. The image plate technology was developed at JAERI on another new protein crystallography station called BIX-3. The two stations have recently started to produce results.
The construction of the PCS at the Los Alamos Neutron Science Center has added to the rebirth of this field. The PCS explores the capabilities of spallation neutrons. Next-generation spallation sources are being built throughout the world and offer the promise of significant gains (in performance and also an increase in the number of protein crystallography stations).
We must emphasize that the increasing availability of optimized neutron protein crystallography stations in general, and not the unique capabilities of the PCS, has made possible a number of recent neutron diffraction studies of large proteins. Readers who are interested in carrying out experiments are welcome to contact us for information on the proposal process and for technical advice.