Publikationsdatenbank

Identification of the novel Macrolide-Lincosamide-Streptogramin B resistance gene erm(54) in a porcine LA-MRSA ST398 (2023)

Art

Poster

Autoren

Krüger-Haker, H. (WE 7)

Ji, X.

Hanke, D. (WE 7)

Schink, A. - K. (WE 7)

Fiedler, S.

Kaspar, H.

Wang, Y.

Schwarz, S. (WE 7)

Wu, C.

Feßler, A. T. (WE 7)

Kongress

Tagung der DVG-Fachgruppe Bakteriologie & Mykologie

Berlin, 22.05. – 25.11.2023

Quelle

Tagung der DVG-Fachgruppe Bakteriologie & Mykologie : 22. bis 24. Mai 2023 — Wissenschaftliche Leitung: Prof. Dr. Stefan Schwarz & Prof. Dr. Marcus Fulde, Berlin Veranstalter und Organisation: DVG Service GmbH, Gießen (Hrsg.)

1. Auflage

Gießen: Verlag der DVG Service GmbH, 2023 — S. 99–101

ISBN: 978-3-86345-666-5

Sprache

Englisch

Verweise

URL (Volltext): https://www.dvg.net/fileadmin/Bilder/DVG/PDF/Gesamtdatei_Tagungsband_Bak-Myk_2023.pdf

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

Introduction:
Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) represent a possible health risk for humans, especially for those having frequent contact to livestock. LA-MRSA are mainly associated with sequence type (ST) 398 in many parts of the world and often multiresistant to antimicrobial agents. Here, a total of 178 porcine LA-MRSA isolated in Germany from 2007-2019 was investigated for new antimicrobial resistance genes.

Methodology:
Whole-genome sequencing was performed on Illumina MiSeq and PacBio Sequel II platforms followed by hybrid assembly and sequence analysis.
Plasmid pHKS3860 was extracted by alkaline lysis and transferred into S. aureus RN4220 via electrotransformation. Antimicrobial susceptibility testing
via broth microdilution and agar disc diffusion was conducted according toCLSI to confirm the functionality of erm(54). An erm(54)-specific PCR assay
was developed and applied to 30 macrolide-resistant staphylococcal isolates, which harbored next-related genes alone or in combinations.

Results:
A novel Macrolide-Lincosamide-Streptogramin B (MLS B) resistance gene, erm(54), was detected on the non-conjugative plasmid pHKS3860 of 36,929 bp in a porcine LA-MRSA ST398. The gene encoded a 23S rRNA methylase of 245 amino acids (aa) that was next-related to Erm(B) (72%). Moreover, erm(54) was expressed constitutively. A complex regulatory region composed of a small reading frame for a 30 aa protein and seven pairs of inverted repeats, which can form varying mRNA secondary structures, was detected upstream of erm(54). The transferred erm(54) caused a distinct increase in the minimal inhibitory concentrations of MLS B antibiotics in S. aureus RN4220. The new PCR assay did not detect any of the next-related erm genes available to us, but detected erm(54) in the original strain and the transformants carrying pHKS3860. Heavy metal resistance genes for copper, mercury and cadmium and an ica cluster for biofilm formation were also detected on plasmid pHKS3860.

Conclusions:
The new transferable and functionally active MLS B resistance gene erm(54) was identified in a porcine LA-MRSA ST398 from Germany. The co-location of erm(54) on a plasmid with heavy metal resistance genes may increase the risk for co-selection under selection pressure imposed by heavy metals in animal feed or the environment. Due to this possibility of co-selection and the zoonotic potential, erm(54)-carrying isolates might pose a public health threat in the future.