Construction of a modular plasmid family for chromosomal integration in Bacillus subtilis

► A novel vector family for chromosomal integration in B. subtilis was constructed. ► Unique restriction sites allow simple exchange of all modules. ► Untagged or strep-tagged proteins can be expressed under single-copy conditions. ► Constitutive or inducible promoters and a promoterless lacZ gene are included. ► pMG plasmids show in contrast to pBR322-based vectors no structural instability.