Characterization of Pseudomonas aeruginosa isolated from various environmental niches: New STs and occurrence of antibiotic susceptible “high-risk clones”

ABSTRACT

The aim of this study was to investigate the antimicrobial phenotypes, major virulence factors, and the molecular typing of 66 P. aeruginosa isolates collected from various sources: human patients and hospital environment, raw milk, poultry meat, chicken/sheep fecal samples, wastewater, thermal water, and seawater. All isolates, except one, were susceptible to all tested antibiotics. exoA, lasB, rhlR, and lasR genes were harbored by 60 isolates. Forty-six, 18, and 2 isolates amplified exoS, exoU, and exoS+exoU genes, respectively. Twenty-one isolates showed high elastase and pigment production. The PFGE typing identified 26 pulsotypes. Some pulsotypes included isolates from different environmental niches and areas. Twelve selected isolates were typed by MLST and eight different STs were found, three of them were new. Our results highlighted the dissemination of some clones amongst different settings and the occurrence of antibiotic susceptible ‘high-risk clones’ that might be very harmful when acquiring genes encoding antibiotic resistance.

KEYWORDS:

• P. aeruginosa
• environment
• Virulence
• New STs
• high-risk clones

Acknowledgments

This publication made use of the Pseudomonas aeruginosa MLST website (https://pubmlst.org/paeruginosa/) developed by Keith Jolley and sited at the University of Oxford (Jolley & Maiden 2010, BMC Bioinformatics, 11:595). The development of this site has been funded by the Wellcome Trust. Part of this study was presented at the 16th International Congress on Pseudomonas (Nº P119, Liverpool, UK, 5–9 September 2017).

Conflict of Interest

The authors declare that they have no conflicts of interests.

Additional information

Funding

This work was supported by the Instituto de Salud Carlos III of Spain (ISCIII) [project PI16/01381] (Co-funded by the European Regional Development Fund [FEDER] ‘A way to make Europe’). Lidia Ruiz-Roldán had a predoctoral fellowship from the Consejería de Industria, Innovación y Empleo, Gobierno de La Rioja, Spain. Bel Hadj Asma has a fellowship from the Tunisian Ministry of Higher Education and Scientific Research.