Rigshospitalet Researchers Yield New Data on Pseudomonas aeruginosa (Mutations in the efflux pump regulator MexZ shift tissue colonization by Pseudomonas aeruginosa to a state of antibiotic tolerance).

Researchers at Rigshospitalet have discovered that mutations in the efflux pump regulator MexZ can lead to Pseudomonas aeruginosa bacteria colonizing human airway tissue and becoming tolerant to antibiotics. These mutations, which are frequently acquired during early stages of lung infection, cause the bacteria to accumulate inside the epithelial barrier and overexpress the gene lecA, which is involved in tissue invasiveness. This overexpression is caused by an imbalance between the MexXY and MexAB efflux pumps. The study suggests that these mutations affect quorum sensing-regulated pathways, promoting tissue invasiveness and protecting the bacteria from antibiotics. [Extracted from the article]