Help: E.coli recA+ strain with chromosomally encoded IPTG-inducible
T7-polymerase, not containing a prophage.
I want to establish simultaneous expression of two proteins from two
different plasmids. One protein is T7 controlled, and the other is under
control of the mitomycin C-inducible SOS-promoter
For optimal induction with mitomycin C, an E. coli recA+ strain is
necessary. Unfortunately, the Novagen BL21DE3 strain lyses upon a
SOS-response, and HMS174 is recA-. I know the Invitrogen corporation sells
an M13 phage containing the T7 polymerase, but I'm looking for simultaneous
expression in a recA+ strain with chromosomally encoded IPTG-inducible T7
polymerase, not containing a prophage or a phage.
My question is this: does anyone know if an E.coli recA+ strain without a
prophage but with chromosomally encoded IPTG-inducible T7-polymerase
Thank you in advance for your cooperation.
vdwal at bio.vu.nl
Fimme Jan van der Wal
Faculty of Biology
dep. Molecular Microbiology
Vrije Universiteit A'dam
de Boelelaan 1087
1081 HV Amsterdam, The Netherlands