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Oxacillinase (OXA)-48-like β-lactamases are the most common carbapenemases in Enterobacterales in certain regions of the world and are being introduced on a regular basis into regions of non-endemicity. Japan has been characterized by low rates of carbapenemase-producing Enterobacterales, and among them, OXA-48-like carbapenemase-producing isolates are extremely rare. Here we describe a Japanese medical worker, without a history of travel abroad, who was diagnosed as having a community-acquired urinary tract infection, and whose urine sample was found to be positive for OXA-48-like carbapenemase-producing Escherichia coli. None of her close contacts had a history of foreign travel, and the same drug-resistant organism was not observed in other patients who had been hospitalized and undergone environmental culture tests in the same medical institution. This isolate was resistant to penicillins, narrow-spectrum cephalosporins, fluoroquinolones, and cefmetazole, but was susceptible to broad-spectrum cephalosporins, piperacillin/tazobactam, and meropenem and displayed reduced susceptibility to imipenem. The modified carbapenem inactivation test supported carbapenemase production, but inhibitor-based synergistic tests yielded negative results of carbapenemase production. Multiplex polymerase chain reaction revealed the presence of the carbapenemase gene (bla OXA-48) bla TEM and AmpC β-lactamase gene (bla DHA). Singleplex polymerase chain reaction targeting the bla OXA-48 region amplified a product sequencing to nearly the full length (722 bp) and matching 100% with OXA-48. The present case highlights a new concern regarding OXA-48-like carbapenemase-producing Enterobacterales, which remain challenging to detect for clinical laboratories in regions of non-endemicity, and may already be latent in Japan. [ABSTRACT FROM AUTHOR]

• A protein-tethered bilayer lipid membrane (ptBLM) was assembled on SAM/Au. • The ptBLM assembly was monitored by time-resolved SEIRA spectroscopy. • The lipid bilayer formation kinetics was influenced by protein–lipid interactions. • Protein–lipid interactions improved the electrocatalytic stability of the cNOR. In protein film electrochemistry for redox-active membrane proteins, the reconstitution of protein-tethered bilayer lipid membranes (ptBLMs) can maximize their functionality and stability at electrolyte/electrode interfaces. To understand the impact of protein–lipid interactions on the ptBLM formation, we tracked the reconstitution process of a lipid bilayer in the presence or the absence of a transmembrane enzyme of cytochrome c -dependent nitric oxide reductase (cNOR) on a mixed self-assembled monolayer (SAM)/Au electrode. Time-resolved surface-enhanced infrared absorption (SEIRA) spectroscopy and electrochemical measurements revealed that the protein–lipid interaction affected the formation kinetics for the phospholipid bilayer and the electrocatalytic stability of the cNOR-modified electrode but not the fluidity of the phospholipid bilayer. Image, graphical abstract [ABSTRACT FROM AUTHOR]