If your purpose is just for doing transformation, harvest and miniprep your vector from DH5a, then it should be ok.

If you want to use this promoter to express gene in E. Coli DH5a, it is another story. If so, what species does this EF1alpha promoter come from? Plants (for example)? Some plants' promoter are not active (doing gene expression) in bacteria. But, EF1alpha gene is pretty conserved, so it might work, I am not sure. You can do a quick cloning and put a GFP gene behind the promoter to see whether the bacteria glow green......

These are two different things.

People have vector with EF1a promoter store in DH5a bacteria. See below vector.

Vector pEF-GFP, a mammalian expression vector for expression of GFP (using EF1a promoter), is grown in bacteria DH5alpha. https://www.addgene.org/11154/

Which organism does the promoter come from? I use the soybean EF1a promoter a lot in my current research, and it transforms well into dh5a using our expressions vectors.

Hi Andika Gunadi,

I know both EF1a and 35S promoter are both constitutive promoter. Why does your lab opt EF1a promoter for gene expression? Most of the people use 35S promoter. Just curious.

@ Ani Ben,

What are you going to do with it after your vector is transformed into DH5a competent cells? Grow the bacteria, miniprep and harvest your vector?

@Yuan-Yeu Yau, my lab is a plant promoter characterization lab, so we find and use various promoters that regulate diverse strength, tissue specificity, inducibility etc. The soy EF1a is one of the strongest constitutive promoter for gene expression in legumes, so it has a wide array of applications.

Hi Andika Gunadi,

Thanks for your response. When you said that you transferred (transformed) DH5a with the vector containing EF1a promoter, was it just for cloning purpose to obtain the final plasmids through miniprep, right? Not for expressing purpose, right?

Yes, we don’t look for expression in E. coli, just for cloning and plasmid extraction.