Freezing of concentrated OP50

I am currently doing liqiud media testing with c elegans and often find that I have large amounts of concentrated OP50 in surplus. I grow the bacteria in 2X YT broth over night at 37 degrees and spin it down, rinsing the broth out with M9 buffer. Is there a good way to freeze concentrated amounts of OP50? So that it can be thawed and used for liquid media testing?

Hope someone can help :slight_smile:

Lisbeth

Back when I was growing worm in liquid culture for microarray experiments, I used the methods from Stuart Kim’s lab - growing large amounts of WT E. coli (Na22, HB101) in SuperBroth and a fermenter. You may not have access to a fermenter, but if you have excess bacteria then the second part of the method will probably work for you. Resuspend the bacteria in M9 that has 20% glycerol. See Kim lab methods here http://cmgm.stanford.edu/~kimlab/index_methods.html