Glycerol Stock Preparation for S. elongatus
Akashdutta
Abstract
Bacterial cultures in the form of agar plates or liquid cultures are not suitable for long term storage at low temperatures such as 4 degrees. Long-term storage of bacteria is best at temperatures around -80 degrees. However, agar plates and liquid cultures cannot be stored at such temperatures, as the water crystallizes in and around the bacterial cells, rupturing and killing them. Glycerol or DMSO (anti-freezing agents) is added to the media to store samples at such temperatures.
Steps
To make n stocks, take an aliquot of the S. elongatus culture such that the OD times the volume is at least 5n.
Centrifuge this aliquot in a falcon at 5000rpm,25°C
Discard the supernatant.
Resuspend the pellet in the minimum amount of BG11 medium required to do so.
Add n mL of 25% glycerol and mix well.
Separate equally into n cryovial tubes.
Store in the stocks in -80°C
.