FIG 3.

Influence of YvnA on pulcherriminic acid biosynthesis. (A) Effects of yvnA on pulcherriminic acid production. The DW2 ΔyvnA ΔyvmB strain was set as a control to exclude the effects of yvmB. DW2/pHY-yvnA and DW2 ΔyvnA ΔyvmB/pHY-yvnA did not produce pulcherriminic acid (data not shown). (B) Effects of yvnA deletion and overexpression on gene transcription. (C) Binding of the YvnA protein to the promoter regions of yvmC and yvmB. Gel shifts of the labeled P2-yvmC (87 bp) and P2-yvmB (87 bp) probes by the YvnA protein are shown. The concentrations of YvnA in lanes 1 to 8 were 0, 1, 2, 5, 0, 1, 2, and 5 ng/μl, respectively. Twenty nanograms of the P2-yvmC (lanes 1 to 4) or P2-yvmB (lanes 5 to 8) probe was added to each lane. The nonspecific competitor poly(dI-dC) was added to the EMSA binding buffer. (D) Expression-level comparisons of PyvmC-amyL and PyvmB-amyL transcriptional fusions. The amyL gene on the chromosome was deleted in DW2 ΔyvmB and DW2 ΔyvmB ΔyvnA for the construction of DW2 ΔyvmB ΔamyL and DW2 ΔyvmB ΔyvnA ΔamyL, respectively. pHY-PyvmC-amyL was transformed into DW2 ΔyvmB ΔamyL and DW2 ΔyvmB ΔyvnA ΔamyL to construct DW2 ΔyvmB ΔamyL/pHY-PyvmC-amyL and DW2 ΔyvmB ΔyvnA ΔamyL/pHY-PyvmC-amyL, respectively. pHY-PyvmB-amyL was transformed into DW2 ΔyvmB ΔamyL and DW2 ΔyvmB ΔyvnA ΔamyL to construct DW2 ΔyvmB ΔamyL/pHY-PyvmB-amyL and DW2 ΔyvmB ΔyvnA ΔamyL/pHY-PyvmB-amyL, respectively.