Metallo-sideromycin as a dual functional complex for combating antimicrobial resistance

Area of Science:

• Microbiology
• Infectious Diseases
• Drug Discovery

Background:

• Antimicrobial resistance (AMR) is a growing global health threat.
• Cefiderocol is a sideromycin antibiotic used against Gram-negative bacteria, but resistance is emerging.
• Novel strategies are needed to combat drug-resistant infections.

Purpose of the Study:

• To investigate the synergistic effects of cefiderocol combined with metallodrugs.
• To evaluate the potential of this combination therapy against resistant Gram-negative pathogens.
• To explore the mechanisms underlying the observed synergistic activity.

Main Methods:

• In vitro testing of cefiderocol and colloidal bismuth citrate (CBS) synergy against Pseudomonas aeruginosa and Burkholderia cepacia.
• Assessment of CBS impact on cefiderocol efficacy against biofilms and resistance development.
• In vivo evaluation in a murine acute pneumonia model.
• Investigation of metal ion competition for cefiderocol uptake.

Main Results:

• Strong synergistic antimicrobial activity was observed between cefiderocol and CBS.
• CBS enhanced cefiderocol efficacy against biofilms and resensitized resistant strains.
• Co-therapy significantly increased survival rates and reduced bacterial lung loads in mice.
• Evidence suggests bismuth ions compete with iron for cefiderocol binding, enhancing uptake.

Conclusions:

• Metallo-sideromycin combinations, specifically cefiderocol with CBS, offer a promising strategy against resistant Gram-negative bacteria.
• This combination therapy demonstrates enhanced efficacy, overcomes resistance, and shows therapeutic potential in vivo.
• Understanding the metallo-drug interaction mechanism provides insights for developing next-generation antimicrobial agents.