Composition of M9 media.

sl3wx at sl3wx at
Wed Oct 11 13:42:27 EST 1995

Hi netters,
I would be grateful for some information regarding minimal medium. 
I am trying to express a protease via E.coli XL-1 . The bug grows very 
slowly in LB media (the expression vector is pIN-III-ompA 2 ) and I can 
see a band on a Cooomassie Blue gel at a position corresponding to the 
pure enzyme. However the expression level is not very high and I suspect
the promoter may be leaky. I tried M9 media (according to Maniatis) but 
after innoculation of a colony into 5ml media the flask shows no turbidity
even after 24 hrs. 
My questions are
1) Can anyone provide me with a recipe for Minimal Media that worked fine
for them???
2) How long is one expected to wait to observe growth??
 Look forward to assistance.
Thanks in advance

More information about the Methods mailing list