2-Aminoimidazole Analogs Target PhoP Altering DNA Binding Activity and Affect Outer Membrane Stability in Gram-Negative Bacteria

Multidrug-resistant bacteria cause immense public health concerns as once effective antibiotics no longer work against even common infections. Concomitantly, there has been a decline in the discovery of new antibiotics, and the current global clinical pipeline is woefully inadequate, especially against resistant Gram-negative bacteria. One major contribution to Gram-negative resistance is the presence of a protective outer membrane. Consequently, an appealing option for tackling resistance is to adversely affect that outer membrane. With that in mind, we define the response regulator PhoP as a target for new 2-aminoimidazole compounds and show that they affect the integrity of the outer membrane in resistant strains of <i>Escherichia coli</i> and <i>Klebsiella pneumoniae</i>. We also provide empirical evidence for the 2-aminoimidazole mechanism of action.