Fig. 5: Small-molecule compounds inhibit OmpV-mediated adhesion and BEV internalization.

a–d Biacore SPR kinetic analyses of C607-0736 (a), E521-1356 (b), Y020-0697 (c), and S823-2720 (d) binding to OmpV. Sensorgram and saturation curve of the titration of different substrates on OmpV immobilized on a CM5 chip. e–h Adherence of V. cholerae WT and ΔompV incubated with or without the small-molecule inhibitors C607-0736 (e), E521-1356 (f), Y020-0697 (g), and S823-2720 (d) to Caco-2 cells (n = 3 independent experiments). i–l Membrane fusion mediated by BEVs derived from the WT and ΔompV strains incubated with or without small-molecule inhibitors was observed via confocal microscopy (i, k), and the fluorescence intensity of BEVs (j, l) was measured to reflect BEV uptake (n = 15 representative fields of view per group). BEVs were stained with rhodamine isothiocyanate B-R18 (orange), and nuclei were stained with DAPI (blue). Scale bar, 20 μm. m, n CETSA assays and quantitative analysis determined the effect of C607-0736(m) and DMSO(n) on the thermal stability of OmpV-FLAG and RNAP (negative control) at whole-cell level (n = 3 independent experiments). Significance was determined by a two-tailed unpaired Student’s t-test (e–h, j, l, m, n) and is indicated by the p value. *p < 0.05, **p < 0.01, ***p < 0.001; ns no significant difference. The data were presented as the mean ± s.d. (e–h, j, l, m, n). The source data are included in the Source Data file.