FIG. 2.
Stability of R995 and R995ΔincC in different hosts. (A) E. coli host. R995 (□) and R995ΔincC (Δ) in E. coli DF4063 (43). (B) Other gram-negative hosts. R995ΔincC in A. calcoaceticus BD413 (42) (◊), A. tumefaciens A136 (42) (▿), P. aeruginosa PAC452 (43) (Δ), and P. putida ATCC 12633 (6) (○). The results for all hosts with wild-type R995 were indistinguishable from the results for P. aeruginosa, which are displayed here (□). Strains were grown to saturation in the absence of selection and then diluted 105-fold in fresh broth. This procedure was repeated until the strains had grown for at least 65 generations. Growth conditions for all bacteria have been described previously (6, 42, 43). Colonies were screened for the presence of plasmids on medium containing kanamycin or tetracycline.