Cotransformation

[waikhay]

Hi all! :)

I would like to transform 2 plasmids i.e. an expression vector (carrying the
gene of interest) and a reporter vector (into which the promoter of interest
has been cloned) into BL21(DE3) cells. Would you recommend/suggest
transforming both plasmids into the cells at once (cotransform) or
transforming one plasmid after another (i.e. transform the reporter vector
into the cells first, select for transformants, then only transform the
expression vector and select for cotransformants)?

Thanks much,
Waikhay