If your gene is not toxic then E.coli strain BL21(DE3) should do. Just clone the cDNA of your gene (in some cases you might need to codon optimize your gene if the codons used originally are too rare in E.coli which can by done by any company offering DNA synthesis) into one of the pET vector series that has a T7 promoter (any other vector with a IPTG regulated T7 promoter should also work).

Hi Azadeh!

Check the following link. You can choose a plasmid which has different features like the plasmid sizes, the type of a tag and at which at terminus of your protein it will be. Bl21 (DE3) is often a good choose to express many different proteins.

https://www.addgene.org/search/advanced/?q=plasmid+for+e+coli&depositor=&article=&gene=&vector=&tags=&advanced_query=&results_per_page=20&page=1&selected_facets=vector_types_exact%3Abacterial-expression&sort_type=relevance

Hi Azadeh Beygmoradi , BL21 should do it, also check this article, about optimization of promoters, hope it works!!!

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