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tryptone soy broth - (Mar/25/2009 )

we are running out of LB and the new products are still on the board. we now only have tryptone soy broth, can it be used for antibiotic selection or blue white screening? we use DH5 alpha as cloning strain


The difference between the tow mediums is yeast extract.
LB has both tryptone and yeast extract.
The tryptone is used to provide essential amino acids to the growing bacteria.
The yeast extract is used to provide a plethora of organic compounds helpful for bacterial growth.

I don't think that you can use it for antibiotic selection or blue white screening only to sustain your cultures until the LB arrives.


DH5 alpha is thiamine minus . As long as u have thiamine in the trytone or soy i think u should be fine. i really don't see a harm in trying it out.


thx guys. I have tried the soy broth and the result was awesome. The bacteria grow much faster and showed less satellite colonies than on LA plate (the only LA I left) after O/N incubation. I keep on using the remaining plates for screening and so far no problems are encountered.