IncF plasmids were identified in

In a study, where the location of blaCTX-M-15 in E. coli isolates from different countries was investigated, in only 37% of the isolates the blaCTX-M-15 was transferable by conjugation or transformation which correlates well with the transfer ability described in our study ( Coque et al., 2008b). Possible explanation for transconjugation failure could be either plasmid Concanamycin A or transposition of mobile elements (likely ISEcp1-associated) into the chromosome ( Coque et al., 2008b and Poirel et al., 2005).
The replicon types detected among the 31 transconjugants and one transformant are summarized in Table 1. The most frequently detected replicon types among blaCTX-M-15-carrying plasmids are IncF-type plasmids (n = 12) (mostly as multi replicon plasmids with a combination of following replicons: IncFII, IncFIA and IncFIB), followed by IncI1 (n = 8), IncK (n = 3) and IncR (n = 1). Notably, a number of plasmids (n = 8) could not be assigned to any of the tested replicon types.