Colistin-induced transition from non-mucoid to mucoid phenotype in resistant <i>Pseudomonas aeruginosa</i> ST3351
<i>Pseudomonas aeruginosa</i> is an opportunistic pathogen frequently infecting the lower airways of individuals with cystic fibrosis (iwCF). We investigated colistin (CST) resistance mechanisms in <i>P. aeruginosa</i> ST3351 (<i>Psa</i>-ST3351) and their impact on bacterial virulence. <i>Psa</i>-ST3351, a novel CST-resistant sequence type, was isolated from a child with CF. We demonstrate that CST resistance in <i>Psa</i>-ST3351 depends on the addition of 4-amino-4-deoxy-L-arabinose to lipid A. Moreover, exposure to CST induced a non-mucoid-to-mucoid phenotypic switch characterized by enhanced swarming motility, decreased susceptibility to aminoglycosides, impaired ExoS secretion via the type-III secretion system, and increased bacterial competition, all hallmarks of a chronic infection phenotype. CST-treated <i>Psa</i>-ST3351 also exhibited reduced phagocytosis by macrophages, despite the induction of pro-inflammatory cytokines remaining unaffected, and enhanced the pathogenicity in a mouse pneumonia model. These findings suggest that CST-induced mucoid conversion in CST-resistant <i>Psa</i>-ST3351 may contribute to disease progression in iwCF, particularly when CST resistance and mucoid conversion remain undetected during CST nebulized therapy.
Authors
- Guilherme E Paiva
- Marı́a Dolores Alcántar-Curiel (ORCID: https://orcid.org/0000-0002-0761-1045)
- Miguel A. De la Cruz (ORCID: https://orcid.org/0000-0001-6909-2941)
- Marco Gudiño‐Zayas (ORCID: https://orcid.org/0000-0003-3186-6854)
- Miguel Cocotl‐Yañez (ORCID: https://orcid.org/0000-0002-4932-2284)
- Santiago Partida‐Sánchez (ORCID: https://orcid.org/0000-0003-2996-9440)
- Miguel A. Valvano (ORCID: https://orcid.org/0000-0001-8229-3641)
- Araceli Pérez-López (ORCID: https://orcid.org/0000-0002-5399-1958)
- Miguel A. Ares (ORCID: https://orcid.org/0000-0003-2574-958X)
- Nilton Lincopán (ORCID: https://orcid.org/0000-0003-0161-5800)
- Luis Fernando Montelongo-Martínez (ORCID: https://orcid.org/0000-0002-5807-3689)
- Thelma Rizo-Pica (ORCID: https://orcid.org/0000-0002-7073-9009)
- Verónica Roxana Flores-Vega (ORCID: https://orcid.org/0000-0001-8830-4284)
- José Luis Lezana (ORCID: https://orcid.org/0000-0002-5064-4790)
- Roberto Rosales-Reyes (ORCID: https://orcid.org/0000-0001-9519-8766)
- Gabriela Hernández-Martínez (ORCID: https://orcid.org/0009-0002-0909-3883)
- José Ignacio Santos-Preciado (ORCID: https://orcid.org/0000-0001-9298-2926)
- Vianney Ortiz‐Navarrete (ORCID: https://orcid.org/0000-0001-6546-9713)
- Guanbo Wang (ORCID: https://orcid.org/0000-0002-7500-3957)
- Ramón G. Varela-Nájera
Institutions
- Universidad Autónoma de Tlaxcala (MX)
- Queen's University Belfast (GB)
- Nationwide Children's Hospital (US)
- Mexican Social Security Institute (MX)
- Hospital General de México (MX)
- Hospital Infantil de México Federico Gómez (MX)
- Instituto de Estudios Avanzados (VE)
- The Ohio State University (US)
- Instituto Politécnico Nacional (MX)
- Benemérita Universidad Autónoma de Puebla (MX)
- Universidad Nacional Autónoma de México (MX)
Publication Details
- Journal
- Virulence
- Published
- 2025-10-27
- DOI
- https://doi.org/10.1080/21505594.2025.2580097
- Citations
- 1
- Primary Topic
- Antibiotic Resistance in Bacteria
- Type
- article
- Field-Weighted Citation Impact
- 0.59