To clarify: I am not implying that I've worked with many proteins that express better in XL1-blue cells than they would express in BL21(DE3) or such if cloned into a pET vector or similar. In fact I can probably recall only one or two that expressed *better* in XL1 cells. However in the good old days pQE series of vectors was quite commonly used and I had things in that were inherited from others - these 'things' were fairly simple to express in XL1-blue whereas they gave me loads of trouble in other strains and I was too busy/lazy to re-clone them.
Artem > Hello Artem, > > We express almost all our proteins in BL21 derivatives. It sounds > like you've worked with many proteins that express/behave better in > XL1-Blue? > > > ho > UC Berkeley > > ------------------------------------------------------------------------------------------------- > XL1-Blue is a strain of E. coli. Whether it is or isn't an expression host > depends on the definition, and I am not going to argue semantics. > > The T5 promoter works with regular garden variety RNApol of E. coli. > Therefore ANY E. coli strain is an 'expression host' for vectors that > contain this promoter. > > I've expressed many proteins in XL1-Blue and I see no reason why you can't > express yours, either. > > Artem >
