2022 Volume 32 Issue 1 Pages 21-24
A hydrogen atom is one of the major components of biological molecules including proteins, and it is involved in hydrogen-bonds important for structure formation/recognition of molecules and in chemical reactions such as hydrolysis. BIX-3 and BIX-4 in JRR-3 are the neutron diffractometers for biological macromolecular crystallography. Many neutron crystal structures have been determined using BIX-3 and BIX-4 before the earthquake in 2011. Neutron crystal structures of rubredoxin and elastase were determined by using BIX-3. These structural studies indicated that the structural information, including hydrogen atoms, is essential for understanding the molecular mechanisms of the proteins. After the restart of JRR-3, neutron diffraction data with higher resolution than previous studies can be obtained by using a new monochromator installed in BIX-3. The high-resolution data will provide much useful information for structural biology.