FIG 6 .
Growth assay for functional complementation of plasmid-borne PopZAt deletion mutants. RS-popZAt cells with the pSRKGm vector, empty or carrying one of the deletion mutants, were grown for 24 h and the optical density (wavelength = 600 nm) was measured every hour. Positive controls, cells grown in 0.5 mM theophylline to induce chromomosal expression of full-length PopZAt (blue curves); negative controls, cells grown without theophylline (red curves); experimental tests of different plasmid-borne deletion constructs induced for expression by the use of 2.5 mM IPTG without theophylline (i.e., no chromosomal expression of full-length PopZAt) (purple curves). Each curve represents the results of 3 replicates.