Evolved bacterial siderophore-mediated antibiotic cross-protection

Area of Science:

• Microbiology
• Evolutionary Biology
• Infectious Diseases

Background:

• Cefiderocol (CFDC) is a crucial antibiotic for Gram-negative infections, including carbapenem-resistant strains.
• Clinical resistance to cefiderocol and its cross-protection mechanisms are not fully understood.
• Antibiotic cross-protection allows resistant bacteria to shield susceptible neighbors from drug effects.

Approach:

• Experimental evolution was used to generate cefiderocol-resistant bacterial populations.
• Whole genome sequencing identified genetic mutations underlying resistance.
• The study evaluated the fitness costs associated with evolved resistance and cross-protection.

Key Points:

• Cefiderocol-resistant bacteria evolved a novel cross-protection mechanism.
• This cross-protection is mediated by increased secretion of bacterial iron-binding siderophores.
• This mechanism differs from previously known antibiotic degradation-based cross-protection.

Conclusions:

• Evolved cefiderocol resistance can lead to cross-protective social behaviors in bacteria.
• Increased siderophore secretion is a unique mechanism driving this cross-protection.
• Antibiotic resistance can be disadvantageous in drug-free environments, suggesting potential therapeutic strategies.