Seeding allows one to grow crystals in the metastable zone. Crystallization in this zone provides control, reproducibility and an improved likelihood of a successful crystallization experiment. Also, crystals can grow from seeds but cannot spontaneously nucleate. By placing a seed or solution of seeds in a drop which is saturated to the metastable zone, one can use the seeds to grow larger single crystals. By controlling the number of seeds introduced into the drop, one can control the number of crystals grown. It is not practically possible to measure and know the number of seeds introduced to a drop, but by performing serial dilutions from a concentrated seed stock, one can control the number of crystals grown in the drop.

Using the Seed Bead kits, one can create crystal seed stock for subsequent seeding experiments. Crystals are placed in the microcentrifuge tube with the Seed Bead(s) and either vortexed or sonicated to generate a seed stock. Then by performing serial dilutions, one can control the number and size of crystals in the experiment.

The Seed Bead kit is useful for the preparation of seed stocks for automated and semi-automated microseeding (D’Arcy 2007, Harlos 2008).

Each Seed Bead Kit (HR2-320) contains 24 special microcentrifuge tubes, each tube containing a single 3mm PTFE Seed Bead.

Each Seed Bead Steel Kit (HR4-780) contains 24 special microcentrifuge tubes, each tube containing a six 1.6 mm Stainless Steel Seed Beads.

Each Seed Bead Ceramic Kit (HR4-781) contains 24 special microcentrifuge tubes, each tube containing a ten 1.0 mm Zirconium Silicate Ceramic Seed Beads.

Each Seed Bead Glass Kit (HR4-782) contains 24 special microcentrifuge tubes, each tube containing a ten 1.0 mm Glass Seed Beads.

Seed Bead Kit

Seed Bead Steel Kit

Seed Bead Ceramic Kit

Seed Bead Glass Kit

1. Stura, E.A., Wilson, I.A., Methods: A Companion to Methods in Enzymology (1990) 1, 38-49.

2. Stura, E.A., Wilson, I.A., “Seeding Techniques” in Crystallization of Nucleic Acids and Proteins: A Practical Approach. Oxford University Press (1992) 99-126.

3. A method to produce microseed stock for use in the crystallization of biological macromolecules Luft, J.R., DeTitta, G.T. Acta Cryst. (1999). D55, 988-993.

4. J.R. Luft and G.T. DeTitta, Methods in Enzymology (1997) 276, 110-131.

5. Structure of an orthorhombic form of xylanase II from Trichoderma reesei and analysis of thermal displacement. Watanabe et al. Acta Cryst. (2006). D62, 784-792.

6. Crystallization and preliminary crystallographic analysis of p40phox, a regulatory subunit of NADPH oxidase. K. Honbou, S. Yuzawa, N. N. Suzuki, Y. Fujioka, H. Sumimoto and F. Inagaki. Acta Cryst. (2006). F62, 1021-1023 (Used seed bead to optimize)

7. Purification, crystallization and preliminary X-ray diffraction study of human ribosomal protein L10 core domain. Yuji Kobayashi et al. Acta Cryst. (2007). F63, 950-952

8. An automated microseed matrix-screening method. Allan D′Arcy, Frederic Villard and May Marsh. Acta Cryst. (2007). D63, 550-554

9. The role of bias in crystallization conditions in automated microseeding. Edwin Pozharski et al. Acta Cryst. (2008). D64, 1222-1227.

10. Transmission electron microscopy for the evaluation and optimization of crystal growth. Hilary P. Stevenson & Guillermo Calero et al. Acta Cryst. (2016) D72, 603-615.

11. Microseed matrix screening for optimization in protein crystallization: what have we learned? D’Arcy A, Bergfors T, Cowan-Jacob SW, Marsh M. Acta Crystallogr F Struct Biol Commun. 2014 Sep;70 (Pt 9):1117-26. doi: 10.1107/S2053230X14015507. Epub 2014 Aug 29.