e coli strain selection for protein expression - (Jun/23/2010 )

Hello, in our lab we have BL21 pRARE chemically competent cells which I have been told are used in protein expression experiments. Does this mean the pRARE plasmid is already transformed into the strain? If so, how can I then transform in my plasmid expressing my protein? The pRARE gives chloramphenicol resistance while my plasmid gives kanamycin resistance. Should I grow the cells on plates with both or just kanamycin?

Thank you

pRARE has a p15a origin of replication and is therefore compatible with common expression vectors like the pET family who have a ColE1-like origin of replication ...so you don't have to worry!

I would use both antibiotics to prevent plasmid loss of both plasmids!

Good luck for your expression experiments!

Regards,
p

You'll need both antibiotics. You may need chlor in the recovery SOC medium, tho'.

When all else fails, I'd just check with the website...