FIG 1.

MpkB is important for repressing melanin production. (A) Phenotypic tests were performed by inoculating A. fumigatus conidia onto solid MM agar plates with or without sorbitol. Agar plates were incubated for 5 days at 37°C. (B) Numbers of conidia produced in the wild-type, ΔmpkB, and mpkBc (complemented) strains. The results are the averages of three repetitions ± standard deviations. One-way analysis of variance (ANOVA) with Tukey’s multiple comparison test was used for statistical analysis, and an asterisk represents a P value of <0.05. (C) A. fumigatus conidia were inoculated into liquid MM for 72 h at 37°C with 200 rpm shaking. (D) Results of qRT-PCRs showing the A. fumigatus pksP mRNA steady-state levels in the wild-type and ΔmpkB strains grown at 37°C for 24 and 48 h, respectively. The results represent the averages of three repetitions ± standard deviations and are expressed as the cDNA concentration of pksP divided by the cDNA concentration of the β-tubulin gene. The results are the averages of three repetitions ± standard deviation. One-way ANOVA with Bonferroni posttest was used for statistical analysis, and an asterisk represents a P value of <0.05. (E) Visualization of melanin by copper-silver staining of hyphae and conidiophores of wild-type and ΔmpkB strains grown for 48 h at 37°C. Bars, 10 µm.