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BL21A or simliar - (Oct/29/2009 )

My lab has recently started going through a lot of DpnI and I have found a source for the plasmid as well as a method of purification. However, the enzyme needs to be produced in a dam- cell line. The only IPTG inducable cell line I have found seems to be BL21A (DE3) but it was suggested by someone on another site that the person who wrote the paper/used the cell line also created the cell line. I have tried locating the author however the article is over 20 years old and I quickly hit a dead end. I have not been able to find it or an equivalent anywhere. I can find plenty of plasmid propagation cells that are dam- (INV110 SCS110 JM110 GM33) but I cannot seem to find a dam- protein expression line.

Does anyone know where I might be able to acquire BL21A (DE3) or an equivalent? Or can anyone suggest something else entirely?

Thanks so much!


buy it or get it from some ppl working in molecular lab close to you.
BL21 (DE3) is a pretty common strain especially if the lab is working on protein expression.


I have plenty of BL21 and many derivatives. I cannot find BL21A which is a dam- expression line.