Microenvironment-Activated Nanozyme-Armed Bacteriophages Efficiently Combat Bacterial Infection

Area of Science:

• Biomaterials Science
• Nanotechnology
• Microbiology

Background:

• Bacterial infections pose significant public health challenges, necessitating novel therapeutic strategies.
• Current treatments face limitations, driving the need for innovative antimicrobial agents.

Purpose of the Study:

• To develop and evaluate a phage-armed palladium (Pd) nanozyme system (phage@Pd) for combating bacterial infections.
• To assess the efficacy and safety of the phage@Pd system in vitro and in vivo.

Main Methods:

• Fabrication of phage@Pd nanohybrids, leveraging phage's host-specific targeting and Pd nanozymes' catalytic activity.
• Evaluation of phage@Pd's bactericidal activity against planktonic bacteria, biofilms, and in vivo infection models (pneumonia, abscess).
• Assessment of the system's safety profile in healthy tissues by analyzing its pH-dependent activity.

Main Results:

• Phage@Pd precisely targets and adheres to Escherichia coli, with Pd nanozymes generating hydroxyl radicals in acidic infection environments.
• The system demonstrates significant bactericidal efficacy against planktonic bacteria and bacteria within biofilms.
• In vivo studies showed phage@Pd effectively eliminated infections in acute bacterial pneumonia and subcutaneous abscess models, promoting tissue recovery.
• Phage@Pd exhibited safety in healthy tissues due to its inertness at physiological pH.

Conclusions:

• The phage@Pd nanohybrid system is a safe and effective antimicrobial agent.
• This approach offers a new strategy for developing advanced antibacterial materials.
• The phage@Pd system shows potential for broad-spectrum antimicrobial applications.