Confocal Science (CFS) : C-Kit Ground Pro XRD

To grow high quality protein crystals

C-Kit Ground Pro XRD

• This is a kit that allows easy optimization of crystallization conditions to grow high quality protein crystals.
• XRD = C-Kit Ground Pro XRD is for X-ray diffraction
• This kit contains two types of experimental tools; one is for the counter diffusion method (CD) and the other is for the diffusion pair under osmotic concentration method (DPOC). The instructions for both methods are included in the kit.
• Counter diffusion method (CD) is an established method for apo- and complex- protein crystal growth. It’s self-searching mechanism increases the probability of generating high quality protein crystals. In addition, diffusion process decreases the concentrations of co-existing small molecules around protein, so that the crystallization conditions are less affected by contaminated chemicals in protein than the conventional vapor diffusion method (VD). Seeding is also available in this method for the robust crystallization.
• Diffusion pair under osmotic concentration method (DPOC) is a new method. In this method, the precipitant and the protein are tandemly loaded to form a diffusion pair in a silicon tubing. They diffuse into each other and are osmotically concentrated at the same time. As a result, protein is crystallized by both VD and CD mechanisms. DPOC is recommended in the cases when the protein concentration is not optimal, the quantity of the ligand for the co-crystallization is limited, or when CD generates no crystal. Seeding is also available in this method for the robust crystallization.

Principle of counter-diffusion method

The counter-diffusion method is a crystallization method in which the protein sample and the crystallization reagent are mutually diffused in the capillary. Protein molecules diffuse from the inside to the outside of the capillary, and crystallization reagent molecules diffuse from the outside to the inside of the capillary, forming a concentration gradient within the capillary. A wide range of concentration conditions is realized in the capillary over time, and crystal growth starts when the crystal growth conditions are realized. Therefore, by setting the concentration of the crystallization reagent in the external solution high, it is possible to easily search for a wide range of crystallization conditions. In other words, with the counter-diffusion method, you are screening an infinite number of crystallization conditions in a single capillary.

Catalog Number	Product Name	Size
CFS-CRT101-1	C-Kit GroundPro (XRD)	1 Set

Item	Quantity	Counter diffusion method (CD)	Diffusion pair under osmotic concentration method (DPOC)	Details
Capillary	15	〇		Glass capillary (ID 0.5 mm, OD 1.2 mm, length 47 mm).
Gel-tube	18	〇		ID 1 mm, OD 2 mm, length 10 mm
5mL test tube	23	〇	〇	For incubating loaded samples
DPOC-tube	8		〇	Silicon tube (ID 1.0 mm, OD 2.0 mm, length 39.5 mm) without an osmo-resistant cover.
C-Cap	16		〇	For protect DPOC-tube ends from osmotic pressure.
Silicon-tube	50cm		〇	For sample loading
Instruction Manual	1	〇	〇
Sealing compound	1	〇	〇

 

References

1) Tanaka, Hiroaki, et al. "A simplified counter diffusion method combined with a 1D simulation program for optimizing crystallization conditions." Journal of synchrotron radiation 11.1 (2004): 45-48.

2) Takahashi, Sachiko, et al. "JCB-SGT crystallization devices applicable to PCG experiments and their crystallization conditions." International Journal of Microgravity Science and Application 36.1 (2019): 360107.