thus the runaway replication plasmid antibacterial strategy of the invention comprises the following basic components 1 a plasmid that alone or with the assistance of a helper plasmid comprises the genes necessary to effect conjugative transfer of the plasmid from a donor cell to a recipient cell the replication of the plasmid is negatively controlled by a gene that can be de activated via mutation so as to release the negative control on plasmid replication referred to as a u201c runaway replication plasmid u201d 2 optionally a helper plasmid with the requisite transfer genes and 3 a donor cell for maintaining the runaway replication plasmid in a replication suppressed state so as not to be killed by the plasmid a number of conjugative plasmids have been well characterized and can serve as subjects for mutagenesis to create runaway mutants which may be used in embodiments of the present invention such mutants contain all components needed for conjugative self transfer from donor to recipient cells but are defective in their replicative repressor rep function examples of such mutants both broad range and narrow range are known in the art haugan et al plasmid 33 27 39 1995 molin et al j bacterial 143 1046 1048 1980 toukdarian amp helinski gene 223 205 211 1998 a particularly preferred plasmid of this type is a mutant of plasmid r6k as described in detail in examples 1 and 2 other examples include but are not limited to rk2 pcu1 pl5a pip501 pam u03b2t and pcrg1600 as an alternative to the use of mutants it may sometimes be preferable to use various components of conjugative plasmids whose features are well understood to create plasmids having.