Frameshift Mutations in Genes Encoding PBP3 and PBP4 Trigger an Unusual, Extreme β-Lactam Resistance Phenotype in .

In our curated panel of complex isolates, strain AU28442 was unusually highly β-lactam resistant. To explore the molecular mechanisms leading to this phenotype, we performed whole genome sequencing (WGS) and microbiological and biochemical assays. WGS analysis revealed that strain AU28442 produced two β-lactamases, AmpC22 and a novel PenA-like β-lactamase denominated PenA39.

Cefepime-taniborbactam demonstrates potent activity vs with .

Taniborbactam (formerly VNRX-5133) is a novel, investigational boronic acid β-lactamase inhibitor. The combination of cefepime (FEP) with taniborbactam is active against carrying class A, B, C, and/or D enzymes. We assessed the activity of FEP-taniborbactam against clinical strains carrying ( = 50, 100%), of which 78% harbored at least one extended-spectrum β-lactamase (ESBL).

Demographic Differences in Emergency Room Epistaxis Treatment Patterns and Outcomes.

Objective: Investigate the association between demographic characteristics and emergency department (ED) epistaxis management and outcomes.

Study Design: Retrospective cohort study.

Setting: TriNetX US collaborative database.

The interaction of the azetidine thiazole side chain with the active site loop (ASL) 3 drives the evolution of IMP metallo-β-lactamase against tebipenem.

Imipenemase (IMP) metallo-β-lactamases (MBLs) hydrolyze almost all available β-lactams including carbapenems and are not inhibited by any commercially available β-lactamase inhibitor. Tebipenem (TP) pivoxil is the first orally available carbapenem and possesses a unique bicyclic azetidine thiazole moiety located at the R2 position. TP has potent activity against producing extended-spectrum and/or AmpC β-lactamases.