Restoration of the Antibiotic Susceptibility of Methicillin-Resistant <i>Staphylococcus aureus</i> and Extended-Spectrum β-Lactamases <i>Escherichia coli</i> Through Combination with Chelerythrine
Mingzhi Wang, Bo Ma, Yunfeng Ni, Xiaoyan Xue, Mingkai Li, Jingru Meng, Xiaoxing Luo, Chao Fang, Zheng Hou
Abstract
Multidrug resistance poses a severe threat to public health and urgently requires new solutions. The natural product chelerythrine (CHE) is a benzophenanthridine alkaloid with antimicrobial potential. In this study, CHE was effective against seven gram-positive bacterial strains, and the minimum inhibitory concentrations (MICs) ranged from 2 to 4 μg/mL. By contrast, CHE showed inferior antibacterial activities against 11 gram-negative strains, and the MICs varied from 16 to 256 μg/mL. We also determined the synergistic/additive effects of combining CHE with nine currently used antibiotics. CHE restored the antibacterial efficacy of the antibiotics against methicillin-resistant Staphylococcus aureus and extended-spectrum β-lactamases producing Escherichia coli . This study suggests that the combination of CHE with conventional antibiotics may be a promising strategy to combat infections caused by multidrug-resistant organisms.