Fig. 4: Redox-signal transduction by MgrA to vancomycin resistance is achieved by regulating cell wall thickness and cell autolysis.
a, b Cell wall thickness was measured by transmission electron microscopy (TEM). Representative TEM images of the WT, mgrAC12S and Δnos strains cultured with shaking at 220 rpm for 16 h at 37 °C are displayed (a). Scale bar = 500 nm. Cell wall thickness of n = 5 individual cells from each strain were measured three times randomly and expressed as means with SD (b). Triton X-100-induced autolysis of the WT and Δnos strains (c) or the WT and mgrAC12S strains (d) was measured in Tri-HCl buffer supplemented with or without 5 μM SNP (displayed as N-5 or N-0). The percentage of the initial OD600 was displayed. Data are means of n = 3 biological replicates with SD. e The transcriptional levels of the indicated genes that reported to regulate autolysis activity were tested in the WT and mgrAC12S mutant strains by using qRT-PCR. Data are means of n = 3 biological replicates with SD. The transcriptional levels of lytN and sarV were measured in both strains after incubation with different concentrations of SNP (f) or H2O2 (g) as indicated. Data are means of n = 3 biological replicates with SD. Two-sided unpaired Student’s t-test, *p ≤ 0.05; ***p ≤ 0.001; ****p ≤ 0.0001; ns not significant (b, e, f, g). Source data are provided as a Source Data file.
