AUTHOR=Liu Xiaoye , Zhang Yafei , Li Zengshun , Zhang Pengpeng , Sun Ying-Jian , Wu Yi-Jun 

TITLE=Paeoniflorin Derivative in Paeoniae Radix Aqueous Extract Suppresses Alpha-Toxin of Staphylococcus aureus

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.649390

DOI=10.3389/fmicb.2021.649390

ISSN=1664-302X

ABSTRACT=<p>The emergence and dissemination of bacterial infections is paralyzing our public health systems worldwide. Worse still, there are no effective antibiotics against bacterial toxins, which facilitate the infection. Natural herbs that target bacterial toxins may be a better choice for therapy of infectious diseases. However, most natural drugs present unknown compositions and unclear mechanisms. Here we demonstrated that the Chinese herb Paeoniae Radix aqueous extract (PRAE) could suppress alpha-toxin (α-toxin) of <italic>Staphylococcus aureus</italic>. We observed that the paeoniflorin derivative (PRAE-a) derivative in PRAE significantly abolished the hemolytic activity of <italic>S. aureus</italic> α-toxin. The analyses of high-performance liquid chromatography (HPLC), mass spectrometer (MS), Fourier transform infrared spectrometer (FTIR), and nuclear magnetic resonance (NMR) showed that PRAE-a was a glycoside compound with a paeoniflorin nucleus. We further found that PRAE-a disrupted the pore-forming ability of α-toxin by prevention of the dimer to heptamer. Therefore, PRAE-a proved to be an effective therapy for <italic>S. aureus</italic> lung infections in mice by inhibiting α-toxin. Collectively, these results highlighted that PRAE-a can be used as an antibacterial agent to attenuate <italic>S. aureus</italic> virulence by targeting α-toxin.</p>