Abstract：
Plasmid-encoded DHA-type AmpCs have been extensively reported in Enterobacterales. The expression of the genes encoding these plasmid-mediated enzymes are inducible and these enzymes are capable of conferring resistance to a wide spectrum of beta-lactams including penicillins and broad-spectrum cephalosporins. The identification of infections caused by AmpC-producing bacteria is a necessity, both for infection control/epidemiology purposes and to inform treatment choices. A common testing method for AmpC production in the clinical laboratory setting is to supplement Mueller-Hinton agar plates used for antibiotic disk diffusion with cloxacillin, a potent inhibitor of AmpC enzymes. Here we describe a novel DHA variant, produced by a clinical Escherichia coli isolate, which is resistant to cloxacillin inhibition.
摘要：
质粒编码的DHA型AmpC已在肠杆菌中广泛报道。编码这些质粒介导的酶的基因的表达是可诱导的,并且这些酶能够赋予对广谱β-内酰胺包括青霉素和广谱头孢菌素的抗性。鉴定由产生AmpC的细菌引起的感染是必要的，既用于感染控制/流行病学目的，也用于指导治疗选择。在临床实验室环境中，AmpC生产的常用测试方法是补充用于抗生素圆盘扩散的Mueller-Hinton琼脂平板，AmpC酶的有效抑制剂。在这里，我们描述了一种新的DHA变体，由临床大肠杆菌分离株产生，对氯唑西林抑制有抗性。
