Introduction to the XZ™ plates.
Dialysis and the XZ™ plates
Dialysis protein crystallization is a well-established method for protein crystallization developed during the early days of structural biology. Dialysis is the only technique that allows crystallization of a biological macromolecule by either salting in or salting out. Although it is a proven crystallization method, that has been used to crystallize and solve the structure of hundreds of proteins (examples listed below), it has been labor intensive and required significant amounts of protein.
- Aspartate carbamoyl transferase (Steitz et.al. PNAS)
- Poliovirus (Hogle et.al. Science)
- Theiler’s murine encephalomyelitis virus (Grant et.al. PNAS)
- Liver alcohol dehydrogenase (Cho et.al. Biochemistry)
- Neuroaminidase (Vargese et.al. J.Mol.Bio.)
- L-arabinose binding protein (Quiocho et.al. Nature)
- Photosystem I reaction centre (Krauss et.al. Nature)
The disposable XZ™ microfluidic dialysis technology has been developed to specifically address these issues. With the XZ™ microfluidic dialysis technology, dialysis protein crystallization trials as low as 15nL/reaction can be easily and quickly setup. This reaction volume represents a reduction in protein consumption per experiment that is > 3,000 times lower than the currently available dialysis products. Another major advantage of the XZ™ plates is its high-throughput compatibility with common liquid dispensing and imaging systems. In addition, the XZ™ microfluidic dialysis technology offers a clear path to structure due to straight forward scale-up designs, easy loop access for crystal harvesting, and in-situ x-ray diffraction capability.
XZ™ design
The XZ™ dialysis protein crystallography plate is composed of a microfluidic plate bonded to an open bottom microtiter plate. The microfluidic plate contains a microfluidic network on the bottom which delivers a protein sample solution to the dialysis chambers. The microfluidic plate is sealed on the bottom (microfluidic channel side) with a clear film and on the top with dialysis membrane discs over the dialysis chambers. The dialysis disc side of the microfluidic plate is then bonded to an open-bottom microtiter plate.
For Formulation of the Salting In/Salting out screen please
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