UCM53 is an inhibitor of bacterial cell division. It binds to the GTP site of the cell division protein FtsZ from B. subtilis in a fluorescent anisotropy assay. In B. subtilis, UCM53 (3 μM) reduces the number of FtsZ rings and increases the number of foci, as well as induces filamentation when used at a concentration of 12 μM. It is active against laboratory strains and clinical isolates of the Gram-positive bacteria B. subtilis, S. aureus, E. faecium, and E. faecalis (MICs = 2-8 mg/L) but is less effective against S. pneumoniae and the Gram-negative bacteria P. aeruginosa, E. coli, and K. pneumoniae (MICs = 32-128 mg/L). UCM53 inhibits cell growth in a panel of cancerous (IC50s = 16.9-76.5 mg/L) and non-cancerous mammalian cell lines (IC50s = 23.5-93.9 mg/L).
