FIG 5.

Genome modification impacts plasmid transfer efficiency and electrotransformability. (A) OG1RF wild type, the ΔEfaRFI mutant, and the ΔEfaRFI::EfaRFIpro-complemented strain were used as pCF10 donors in conjugation reactions with OG1SSp as the recipient. In this experimental design, the modification status of pCF10 at 5′-GCWGC-3′ motifs varied. For each trial, the pCF10 transfer efficiency (pCF10 transconjugants/donor) from OG1RF to OG1SSp was set to 1. Transfer efficiencies for the other donor strains were expressed relative to this rate. Bars represent mean values, and standard deviations are shown (n = 8 trials for OG1RF and ΔEfaRFI and n = 5 trials for ΔEfaRFI::EfaRFIpro). Significance was assessed by paired t test. (B) Conjugation frequency assessed as described for panel A, but with donor and recipient strains reversed. For these experiments, OG1SSp donated modified pCF10 to OG1RF and its derivatives. The transfer efficiency from OG1SSp to OG1RF was set to 1. Transfer efficiencies for the other recipient strains were expressed relative to this rate. Three independent experiments were performed. (C) EOT assay results. The EOT from modified pMSP3535 was set to 1. The EOT from unmodified pMSP3535 was significantly lower over three independent experiments. **, P < 0.01; ****, P < 0.0001.