Figure 2

Generation and genotype confirmation of the chromosomal and megaplasmid par mutants. (A) Genotype confirmation of the parABc mutant by Southern blot. The genomic DNA was digested with BamHI and hybridization was performed with a 992-bp biotin-labeled DNA fragment. The in silico predicted sizes are 5.13 kbp for the wild type and 4.68 kbp for ΔparABc. (B) Schematic diagrams showing exchange of the N-terminus-encoding region of ParAm (amino acid positions 1–40) with blm. Gray arrowhead denotes the promoter region of parABm; black arrowhead, promoter of blm. (C) Genotype confirmation of the ΔparAmN-1 and ΔparAmN-2 mutants by Southern blot. The genomic DNA was digested with PstI, the predicted sizes are 2.26 kbp for the wild type and 2.73 kbp for ΔparAmN-1 and ΔparAmN-2. (D) Transcription levels of the truncated parAm and parBm genes in ΔparAmN-1 and ΔparAmN-2 relative to those of the wild type determined by RT-qPCR. Gray bar represents the relative expression level of the truncated parAm, white bar represents that of parBm. The average values and SDs shown are from three experiments.