Scripps acquires Rigaku UV crystal imaging system

Rigaku Americas has announced that it is working with the Joint Center for Structural Genomics (JCSG) on an automated ultraviolet (UV) imaging and protein crystal monitoring system to accelerate identification of crystals to be harvested for X-ray crystallographic structure determination. These new developments, based on the Rigaku Desktop Minstrel UV instrument acquired in 2008 by the JCSG, will supplement the existing large-scale, high-throughput Rigaku CrystalMation system at the JCSG's robotic crystallisation facility housed at The Scripps Research Institute (TSRI).

Protein crystallisation trials at the JCSG rely on automated robotic systems. The introduction of the Rigaku CrystalMation system into the JCSG pipeline has boosted the centre's capacity for crystallisation trials by approximately 4000 96-well plates/month and helped them achieve the phenomenal rate of over 200 unique structures per year. This level of throughput has highlighted areas that have been difficult to automate, such as analysis and scoring of crystallisation trials for the presence of protein crystals.

The UV technology used in the Rigaku Desktop Minstrel UV allows for unambiguous identification of protein crystals, even in drops that contain salt crystals and other amorphous precipitate.

In a recent interview, JCSG researcher Dr Marc Elsliger explains that “in addition to the immediate use of UV imaging to decipher protein from salt crystals, we foresee that this technology can be harnessed for automated identification of protein crystals and, more importantly, a more reliable and quantitative autoscoring of the crystallisation trials”. In discussing the future of robotic crystallisation at the JCSG, he elaborated, “Through a strategic partnership agreement with Rigaku Automation, we aim to attack one of the last few remaining hurdles in fully automated, HT crystallisation screening. We believe that the use of UV crystal imaging integrated with advanced autoscoring algorithms will provide a solution to addressing the current obstacles in automated HT crystal detection and screening.” Experimental work to evaluate and further develop this new system is currently underway.

Rigaku Desktop Minstrel UV is a fully automated ultraviolet imaging and protein crystal monitoring system that uses ultraviolet fluorescence (UVF) microscopy. Engineered and optimised for use in protein crystallisation experiments, this instrument is a major advance over previous visible light microscopy techniques because its UVF technology can easily distinguish protein crystals from non-protein crystals (such as salt). The system is bundled with advanced CrystalTrak software for automatic imaging of crystallisation experiments; furthermore, it links the acquired images with crystallisation conditions in an SQL relational database, providing a complete virtual crystallisation laboratory.