Fig. 1
Clostridial KO vector pMTL-ME3 and pMTL-SC7515. Plasmid components are: CatP, the catP gene of C. perfringens conferring thiamphenicol resistance; Csp-pyrE, the pyrE gene of C. sporogenes; ColE1 RNAII, the replication region of the E.coli plasmid ColE1; traJ, transfer function of plasmid RP4 oriT region; ΩCD0164, a transcriptional terminator isolated from downstream of the C. difficile strain 630 CD0164 gene; lacZα MCS, the lacZ’ gene encoding the alpha fragment of the E.coli β-galactosidase, containing a multiple cloning site, MCS, region derived from plasmid pMTL20; Ω(fdx), a transcriptional terminator of the ferredoxin gene of C. pasteurianum; repL is the replication protein of plasmid pIM13; codA, the cytosine deaminase gene of E. coli, and; the promoter in front of codA is the Pfac promoter of pMTL007