Understanding Murepavadin Resistance in Pseudomonas aeruginosa
Author Information
Author(s): Hernández-García Marta, Barbero-Herranz Raquel, Bastón-Paz Natalia, Díez-Aguilar María, López-Collazo Eduardo, Márquez-Garrido Francesc J., Hernández-Pérez José María, Baquero Fernando, Ekkelenkamp Miquel B., Fluit Ad C., Fuentes-Valverde Víctor, Moscoso Miriam, Bou Germán, del Campo Rosa, Cantón Rafael, Avendaño-Ortiz José
Primary Institution: Servicio de Microbiología, Hospital Universitario Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
Hypothesis
What are the genomic modifications and consequences underlying murepavadin and/or colistin susceptibility in Pseudomonas aeruginosa?
Conclusion
Murepavadin resistance in Pseudomonas aeruginosa is linked to mutations in lpxL1 and lpxL2 genes, leading to lower inflammatory responses and higher susceptibility to host-derived antimicrobial peptides.
Supporting Evidence
- GWAS identified a missense variant in the hisJ gene associated with murepavadin resistance.
- Murepavadin-resistant mutants exhibited lower abundance of hexa-acylated lipid-A.
- Mutants with lpxL1 and lpxL2 deletions showed higher murepavadin MICs than the parental strain.
- Lower inflammatory responses were triggered by lipopolysaccharide from murepavadin-resistant mutants.
- Mutants were more susceptible to host-derived antimicrobial peptides cathelicidin and indolicidin.
Takeaway
This study looks at how some bacteria become resistant to a new antibiotic called murepavadin, which is supposed to help fight infections. It found that changes in the bacteria's genes can make them less responsive to the antibiotic but more vulnerable to the body's natural defenses.
Methodology
The study used a genome-wide association study (GWAS) and paired genomic comparisons to analyze 496 P. aeruginosa isolates and their murepavadin-resistant mutants.
Limitations
The study had a limited number of colistin-resistant isolates, which are rare, potentially affecting the statistical significance of the findings.
Participant Demographics
Isolates were obtained from patients with cystic fibrosis and other respiratory pathologies across multiple countries.
Statistical Information
P-Value
0.012
Statistical Significance
p<0.05
Digital Object Identifier (DOI)
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