Sterilized glass plating beads (4 mm) provide an efficient and easy method to achieve optimal spreading on agar plates. The rolling action of the glass beads gently spread the E. coli solution (or any bacterial /fungal solution) to reach areas of the plate that are inaccessible to spread. Multiple plates containing beads and E. coli solution may be stacked and shaken simultaneously to increase spreading throughout and reduce cell stress. The beads may be recovered by washing with 70% ethanol, then sterilized and dried.
- No flaming required
- Bacterial and fungal solution spreading on agar plates
- Plating yeast for two-hybrid screens
For regular plating of ECOS™ Competent Cells, add 5 ~ 10 beads immediately after pipetting 50 ~ 100 μl of transformed cells onto each plate. Move the plate back and forth to roll the beads on the surface and change the direction of shaking a few times to ensure even spreading. When the surface of the agar starts to dry on the plate (20 ~ 40 seconds), pour off the beads and the plates are ready for incubation.
- Pre-warmed glass beads at 37°C for ECOS™ warm plating (protocol 2&4, page3-3)
- Pre-cooled glass beads at 4°C for ECOS™ cold plating (protocol 1&3, page 3-3)
- Room temperature for SCOS and YLOS Transformation Kits
Each lot of beads has to pass contamination test by spreading sterilized water on agar plates containing no selective antibiotics. No bacterial and fugal colonies should be seen after 2 day incubation.