||A Novel Neutron Diffractometer for Protein Crystallography at J-PARC: Targetting Large Membrane Proteins and Protein Complexes
栗原, 和男 ,
友寄, 克亮 ,
平野, 優玉田, 太郎
The structural information of hydrogen atoms and hydration waters obtained by neutron protein crystallography is expected to contribute to elucidation and improvement of protein function. However, many proteins, especially membrane proteins and protein complexes, have larger molecular weight and then unit cells of their crystals have larger volume, which is out of range of measurable unit cell volume for conventional diffractometers. For this reason, our group had designed the diffractometer at J-PARC which can cover crystals with large unit cell volume. Larger unit cell volume causes a problem to separate spots closer to each other in spatial as well as time dimension in diffraction images. Therefore, our proposed diffractometer adopts longer camera distance (L2 = 800mm) and more than 40 novel large-area detectors (larger than 300mm × 300mm). In addition, decoupled hydrogen moderator is selected as neutron source which has shorter pulse width. This diffractometer is estimated to cover crystals with a lattice length of 220 Å in each axis at d-space of 2.0 Å. Ellipsoidal and curved shape were introduced in the vertical and the horizontal design of the guide design, respectively, which provide about 20 or larger as compared with BIX-3/4 diffractometers operated in the research reactor JRR-3.
第1回QST国際シンポジウム 「量子生命科学 -Quantum Life Science-」