Genomic Epidemiology of C2/H30Rx and C1-M27 Subclades of IEscherichia coli/I ST131 Isolates from Clinical Blood Samples in Hungary

• Published in: Antibiotics (Basel) 2024-04, Vol.13 (4)
• Main Authors: Tóth, Kinga, Damjanova, Ivelina, Laczkó, Levente, Buzgó, Lilla, Lesinszki, Virág, Ungvári, Erika, Jánvári, Laura, Hanczvikkel, Adrienn, Tóth, Ákos, Szabó, Dóra
• Format: Article
• Language: English
• Subjects: Drug resistance in microorganisms; Epidemiology; Escherichia coli; Genes; Genomics; Imipenem; Transposons
• ISSN: 2079-6382; 2079-6382
• DOI: 10.3390/antibiotics13040363

Extended-spectrum β-lactamase-producing Escherichia coli ST131 has become widespread worldwide. This study aims to characterize the virulome, resistome, and population structure of E. coli ST131 isolates from clinical blood samples in Hungary. A total of 30 C2/H30Rx and 33 C1-M27 ST131 isolates were selected for Illumina MiSeq sequencing and 30 isolates for MinION sequencing, followed by hybrid de novo assembly. Five C2/H30Rx and one C1-M27 cluster were identified. C1-M27 isolates harbored the F1:A2:B20 plasmid in 93.9% of cases. Long-read sequencing revealed that bla[sub.CTX-M-27] was on plasmids. Among the C2/H30Rx isolates, only six isolates carried the C2-associated F2:A1:B- plasmid type. Of 19 hybrid-assembled C2/H30Rx genomes, the bla[sub.CTX-M-15] gene was located on plasmid only in one isolate, while in the other isolates, ISEcp1 or IS26-mediated chromosomal integration of bla[sub.CTX-M-15] was detected in unique variations. In one isolate a part of F2:A1:B- plasmid integrated into the chromosome. These results suggest that CTX-M-15-producing C2/H30Rx and CTX-M-27-producing C1-M27 subclades may have emerged and spread in different ways in Hungary. While bla[sub.CTX-M-27] was carried mainly on the C1/H30R-associated F1:A2:B20 plasmid, the IncF-like plasmids of C2/H30Rx or its composite transposons have been incorporated into the chromosome through convergent evolutionary processes.