Structural Biology

X-ray crystallography has been the most widely utilized method for 3D structure determination of biological macromolecules

at atomic resolution. Since modern biology is studied at the molecular level, the 3D structures of biological macromolecules

provide critical information for rational biological studies. X-ray crystallography is therefore becoming an essential tool for

molecular and cellular biology and is increasingly being adopted by non-crystallographers. To facilitate this movement, the

Structural Biology Research Center (SBRC) in KEK has developed several robotics and automation systems for crystallization,

data collection, and structure determination. For the initial crystallization screening, we have developed protein crystallization

system (PXS) that can automatically perform initial crystallization screenings in a sitting drop setting. Th e PXS possesses

an automated image acquisition function for crystallization droplets. Th e obtained images can be checked from outside the

KEK campus via a VPN connection. Moreover, the crystallization plate can be directly mounted to a specifi c goniometer at

BL-17A for in situ data collection. Our protein crystallography beamlines, BL-1A, 5A, 17A, AR-NW12A, and AR-NE3A,

are highly automated by the PReMo program. Once a cassette containing protein crystals is set to the system, a robot can

mount a crystal to the goniometer in a beamline; do the centering of the crystal and start data collection. Beginning in May

2018, we will provide a fully automated data collection service for users. In this service, the obtained diff raction data sets will

be automatically processed by a data-processing routine in PReMo. Th e processed data can then further be analyzed with

PReMo for structural determination using the SAD method. Although at present the structure determination following the

data processing must be performed manually, we are developing a new routine for automated structure determination. It is

of note that all these automated functions are based on a database system in PReMo, and thus data from crystallization to

structure determination can be treated in an integrated manner. Our service is expected to provide the basis of an intelligent

system for crystallography.