FIGURE 1.
Construction and verification of vipp1 mutant as well as a trans-complemented strain. A, scheme showing the construction of a vipp1 mutant by homologous recombination by using primer set p1 and p2 to amplify the upstream region and primer set p3 and p4 to amplify the downstream region. An antibiotic resistance cassette was ligated into restriction sites added to the appropriate ends of the flanking sequences (see “Experimental Procedures” for other details). B, results of agarose gel electrophoresis of amplicons produced using primers p5 and p6, showing the fully segregated interruption mutant of vipp1. The template DNAs were isolated from the wild type (WT), the trans-complemented vipp1 mutant (Comp), and the vipp1 mutant strain (Δvipp1). The results clearly showed that the wild-type vipp1 and interrupted vipp1::aacC1 alleles had segregated completely in the vipp1 mutant and that the vipp1 gene was still mutated in the Comp strain. Lane M, DNA size markers. C, cultures of equivalent cell density (OD730 nm = 1.0) for WT, Comp, and Δvipp1.