Publikationsdatenbank

ESBL-plasmid carriage in E. coli enhances in vitro bacterial competition fitness and serum resistance in some strains of pandemic sequence types without overall fitness cost (2018)

Art

Zeitschriftenartikel / wissenschaftlicher Beitrag

Autoren

Ranjan, Amit

Scholz, Julia

Semmler, Torsten

Wieler, Lothar H (WE 7)

Ewers, Christa

Müller, Stefanie

Pickard, Derek J

Schierack, Peter

Tedin, Karsten (WE 7)

Ahmed, Niyaz

Schaufler, Katharina

Guenther, Sebastian

Quelle

Gut pathogens : the official journal of The International Society for Genomic and Evolutionary Microbiology (ISOGEM)

Bandzählung: 10

Seiten: Artikelnr. 24

ISSN: 1757-4749

Sprache

Englisch

Verweise

URL (Volltext): https://gutpathogens.biomedcentral.com/articles/10.1186/s13099-018-0243-z

DOI: 10.1186/s13099-018-0243-z

Pubmed: 29983750

Kontakt

Institut für Mikrobiologie und Tierseuchen

Robert-von-Ostertag-Str. 7-13
14163 Berlin
+49 30 838 51843 / 66949
mikrobiologie@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Extended spectrum beta lactamase (ESBL)-producing extraintestinal pathogenic Escherichia coli infections are of global interest because of their clinical and economic impact. The ESBL resistance genes disseminate through plasmids, and are found in successful global lineages such as ST131 and ST648. The carriage of plasmids has been suggested to result in a fitness burden, but recently it was shown that ESBL-plasmids enhanced virulence in pandemic ST131 and ST648 lineages without affecting their fitness. Herein, we investigated the influence of ESBL-plasmids on bacterial competition and serum resistance, both of which are essential characteristics of ExPEC during infections.

Triplets of ESBL-plasmid-carrying wildtype (WT), plasmid-cured variant (PCV) and transformant (T) of five ExPEC strains of ST131 and ST648 were used for bacterial competition experiments with colicin-producing commensal E. coli, competitive adhesion experiments and serum survival. In addition, resilience after SDS, acid, osmotic challenges and RNA sequence data were analyzed.

In all five strains tested, ESBL-plasmid carriage did not negatively influence E. coli fitness in direct bacterial competition with commensal E. coli in vitro. That is, WTs did not show any disadvantages when compared to their isogenic plasmid-free PCV. For one strain we even found the opposite as PCV17433 was out-competed by a commensal strain, which suggests an even protective role of the ESBL-plasmid carried by the WT17433. Similarly, in the serum-resistance experiments, the PCVs of two strains (PCV17433 and PCV17887) were more sensitive to serum, unlike WTs and Ts. The observed inter-strain differences could be explained by the different genetic content of plasmids carried in those strains.

Overall, we found no compelling evidence for an increased burden resulting from the carriage of ESBL-plasmids in the absence of antimicrobial selection pressure in the strains of pandemic ST131 and ST648; rather, the possession of certain ESBL-plasmids was beneficial for some strains in regarding competition fitness and serum survival.