Altered regulation of septal peptidoglycan synthesis modulates β-lactam susceptibility in Pseudomonas aeruginosa.

Alterations in the FtsI pedestal domain modulate β-lactam susceptibility and cell division regulation in Pseudomonas aeruginosa, revealing a key regulatory hub.

• Why it matters: Understanding how septal peptidoglycan synthesis is controlled is crucial because its dysregulation affects bacterial growth and antibiotic resistance, especially in pathogenic P. aeruginosa strains.
• What they did: The study identified mutations in the FtsI pedestal domain that bypass FtsN requirements, mapped these onto the FtsQLBWI structure, and tested their impact on antibiotic susceptibility, including in clinical isolates.
• The result: Findings show that specific pedestal domain mutations can either modestly reduce β-lactam susceptibility or cause hypersusceptibility, linking divisome regulation to antibiotic response and highlighting the domain's role as a regulatory hub.