FIG 4.

Effect of the CovSY39H variant on SpeB and SLO production. Shown are the relative abundances of the accumulated SpeB (A and C) or SLO (B and D) in the supernatants of M1-CovS-WT (closed circles) and M1-CovS-Y39H (open squares) grown in THY broth or THY broth with MgCl₂ (A and B) or in THY broth or THY broth with LL-37 (C and D) compared to those in the supernatants of the wild-type strain grown in THY broth. Strains were grown to the late (OD₆₀₀ = 0.6 to 0.7) and early (OD₆₀₀ = 0.3 to 0.4) exponential phases for SpeB and SLO quantifications, respectively. The experiments were carried out for the SpeB and the SLO quantifications 10 and 4 times, respectively. Statistical analysis was performed by a Kruskal-Wallis test with a Dunn posttest and by two-way ANOVA with a Bonferroni posttest for SpeB and SLO analyses, respectively (Prism 9). *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001.