A novel F type plasmid encoding mcr-10 in a clinical Enterobacter ludwigii strain from a tertiary hospital in Czech Republic

Abstract

Objective: Here we describe a novel IncFIA plasmid harboring mcr-10 gene in a clinical Enterobacter ludwigii strain isolated at the University Hospital in Pilsen in the Czech Republic.Methods: The strain was subjected to antibiotic susceptibility testing. Whole genome sequencing was performed using Illumina for short read sequencing and Oxford Nanopore Technologies for long-read sequencing followed by hybrid assembly. The resulting genome was used to detect species using average nucleotide identity, resistance genes, plasmid replicon and MLST (using center for genomic epidemiology databases; ResFinder, PlasmidFinder and MLST repsectively) and virulence genes using VFDB.Results: Τhe strain showed susceptibility against tetracycline, cefuroxime and chloramphenicol, and was susceptible to the 2nd and 3rd generation of cephalosporins, carbapenems and colistin. Genome analysis identified the strain as E. ludwigii sequence type ST20 and located the mcr-10 gene on an IncFIA (HI1)/IncFII (Yp) plasmid (pI9455333_MCR10; 129,863 bp). Upon blasting the nucleotide sequence of pI9455333_MCR10 against NCBI database; no similar plasmid sequence was detected implying a novel plasmid structure. Nevertheless, it showed a partial similarity with: pRHBSTW-00123_3 and FDAARGOS 1432 which were detected in Enterobacter cloacae complex (ECC) strains in wastewater samples in 2017 in UK and in 2021 in the USA respectively, and pEC81-mcr which was detected in a clinical Escherichia coli strain in 2020 in China. Moreover, I9455333cz genome carried virulence genes coding for: curli fibers, fimbrial adherence determinants, siderophore aerobactin, iron uptake proteins, and regulators of sigma factor.Conclusion: In conclusion, we identified a novel IncF plasmid harboring mcr-10 gene in a clinical Enterobacter ludwigii strain. To our knowledge, this is the first clinical report of mcr-10 in the Czech Republic.