Integral genomic description of bla-harbouring plasmids recovered from Enterobacterales in Argentina.

Objective: To characterise four bla-harbouring plasmids recovered in Enterobacterales isolated in Argentina.

Methods: DNA was sequenced by Illumina and Oxford Nanopore Technologies, assembled using Unicycler, analysed using PlasmidFinder, MOB-Typer, IslandViewer4, and Resfinder, and visualised by Proksee and Clinker. bla-harbouring plasmids were compared with similar deposited plasmids using PLSDB.

Re-updating the taxonomy of genus for a better understanding of CTX-M β-lactamase origin.

The taxonomic definitions within the genus are still unclear, as several deposits might belong to misidentified species or genus or genome assemblies comprehend large indeterminate nucleotide zones. In this study, we performed a comparative phylogenomic analysis of chromosomes and other selected . We also included the genomic analysis of chromosomal from isolates and assigned the plasmid-encoded genes.

Crystal structure of the class A extended-spectrum β-lactamase CTX-M-96 in complex with relebactam at 1.03 Angstrom resolution.

The use of β-lactam/β-lactamase inhibitors constitutes an important strategy to counteract β-lactamases in multidrug-resistant (MDR) Gram-negative bacteria. Recent reports have described ceftazidime-/avibactam-resistant isolates producing CTX-M variants with different amino acid substitutions (e.g.

Insights into the activity of cefiderocol against PER-2 producing Enterobacterales.

The PER-2 β-lactamase is a unique class A enzyme conferring broad spectrum cephalosporin resistance. In this study, we explored the stability of cefiderocol (FDC) against PER-2 β-lactamase to gain insights into structure activity relationships (SAR) of this synthetic siderophore-conjugated antibiotic. Herein, we show that the MICs of FDC for PER-2 producing isolates and transformants ranged between 0.