Cloning and expression in minicells of the determinant of resistance to fosfomycin from the transposon Tn2921.

The fosfomycin resistance determinant of the transposon Tn2921 has been localized and cloned into the plasmid pBR322. A DNA fragment of 1 kb contains all the information required for full expression of the resistance. The level of resistance was unaffected by the plasmid copy number and by the orientation in which the fragment was cloned. Studies in minicells showed that this 1-kb fragment directed the synthesis of a single polypeptide with a molecular mass of 16 kDa.