Fig. 5
From: Design of a novel antimicrobial peptide 1018M targeted ppGpp to inhibit MRSA biofilm formation
The abilities of 1018 and 1018M against MRSA biofilms. a Inhibition effect of IDR-1018 and 1018M on biofilms formation. b–d Observation of MRSA ATCC43300 biofilms by CLSM. MRSA ATCC43300 was incubated with 64 μg/mL IDR-1018 (c), 1018M (d) for 24 h, and biofilms were stained with dyes and visualized by CLSM after removing planktonic bacteria. Live cells are stained in green by SYTO9 and dead cells are stained in red by PI. b The untreated biofilm. e–g Observation of MRSA ATCC43300 biofilms by SEM. e Untreated biofilm, f IDR-1018, g 1018M. h Relative gene expressions of biofilms. MRSA ATCC43300 cells were incubated with 4× MIC peptides or no peptide for 2 h and collected by centrifugation. After isolation RNA from cells, the transcriptional levels of ppGpp metabolism and biofilm formation related genes were detected by qRT-PCR. All assays were performed in triplicate. The analyses were measured by one-way ANOVA, with Duncan’s multiple comparisons test. A probability value of < 0.05 was considered significant. (*) Indicates the significance between control and each of treatment groups. * p < 0.05; ** p < 0. 01. The results are given as the mean ± SD (n = 3)