Discovery of Amphiphilic Xanthohumol Derivatives as Membrane-Targeting Antimicrobials against Methicillin-Resistant <i>Staphylococcus aureus</i>

Abstract

Infections caused by multidrug-resistant (MDR) bacteria are increasing worldwide, and with limited clinically available antibiotics, it is urgent to develop new antimicrobials to combat these MDR bacteria. Here, a class of novel amphiphilic xanthohumol derivatives were prepared using a building-block approach. Bioactivity assays showed that the molecule <b>IV15</b> not only exhibited a remarkable antibacterial effect against clinical methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) isolates (MICs: 1-2 μg/mL) but also had the advantages of rapid bactericidal properties, low toxicity, good plasma stability, and not readily inducing bacterial resistance. Mechanistic studies indicated that <b>IV15</b> has good membrane-targeting ability and can bind to phosphatidylglycerol and cardiolipin in bacterial membranes, thus disrupting the bacterial cell membranes and causing increased intracellular reactive oxygen species and leakage of proteins and DNA, eventually resulting in bacterial death. Notably, <b>IV15</b> exhibited remarkable <i>in vivo</i> anti-MRSA efficacy, superior to vancomycin, making it a potential candidate to combat MRSA infections.