Hinokiflavone Attenuates the Virulence of Methicillin-Resistant Staphylococcus aureus by Targeting Caseinolytic...

Area of Science:

• Microbiology
• Pharmacology
• Biochemistry

Background:

• Drug-resistant bacteria, particularly Methicillin-resistant Staphylococcus aureus (MRSA), pose a significant global health threat.
• Caseinolytic protease P (ClpP) is a critical enzyme in MRSA, essential for its survival and pathogenicity, making it a prime therapeutic target.

Purpose of the Study:

• To identify novel natural compounds that inhibit MRSA ClpP activity.
• To evaluate the anti-virulence and anti-infective potential of hinokiflavone against MRSA.

Main Methods:

• Screening of natural compounds for ClpP inhibition.
• Biochemical assays to determine IC50 values.
• Cellular thermal shift assay (CETSA), thermal shift assay (TSA), local surface plasmon resonance (LSPR), and molecular docking (MD) to confirm direct binding.
• In vivo studies using a mouse model of MRSA-induced pneumonia.

Main Results:

• Hinokiflavone demonstrated significant inhibition of MRSA ClpP with an IC50 of 34.36 μg/mL.
• Hinokiflavone reduced MRSA virulence by inhibiting multiple virulence factors.
• Molecular assays confirmed direct binding of hinokiflavone to ClpP at specific sites (SER-22, LYS-26, ARG-28).
• In vivo, hinokiflavone combined with vancomycin provided superior protection against MRSA pneumonia compared to vancomycin alone.

Conclusions:

• Hinokiflavone is a potent inhibitor of MRSA ClpP.
• Hinokiflavone exhibits anti-virulence properties and enhances antibiotic efficacy.
• Hinokiflavone represents a promising candidate for development as an adjuvant therapy against S. aureus infections.