Li Pei, Lei Ting, Zhou Yang, Dai Yujie, Yang Zhishuang, Luo Hongyan
College of Veterinary Medicine, Southwest University, Beibei, Chongqing, China.
Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China.
Microbiol Spectr. 2023 Jan 31;11(2):e0003923. doi: 10.1128/spectrum.00039-23.
A novel chromosome-encoded metallo-β-lactamase (MBL) EBR variant, namely, EBR-5, was identified in a multidrug-resistant Empedobacter stercoris strain SCVM0123 that was isolated from chicken anal swab samples. EBR-5 shared 82.13% amino acid identity with the previously known EBR-1. The expression of EBR-5 in Escherichia coli reduced susceptibility to expanded-spectrum cephalosporins and carbapenems. Compared with , the recombinant strain harboring exhibited higher minimum inhibitory concentrations of piperacillin, cefotaxime, and meropenem. Despite the genetic diversity, EBR-5 and EBR-1 possessed similar kinetic parameters, except for cefepime, cefotaxime, cefoxitin, cephalothin, and meropenem, which were hydrolyzed more by EBR-5. In addition to , a whole-genome sequencing analysis of SCVM0123 also revealed a plasmid-mediated gene. This study underlines the importance of monitoring, as it could be a potential reservoir of these β-lactamase genes. Carbapenemases are one of the greatest threats to clinical therapy, as they could confer resistance by hydrolyzing carbapenems and other β-lactam antimicrobials. In this study, we identified a novel metallo-β-lactamase EBR variant, namely, EBR-5, in Empedobacter stercoris. The biochemical properties, substrate hydrolysis abilities, and inhibition profiles of EBR-5 were reported. Through whole-genome sequencing and bioinformatic analyses, we revealed for the first time that the ESBL gene was located on a plasmid. This study extends the database of class B metallo-β-lactamases. Meanwhile, could be a major reservoir of and , which have potential to spread to pathogens.
在一株从鸡肛门拭子样本中分离出的多重耐药性的粪便埃氏菌菌株SCVM0123中，鉴定出一种新的染色体编码金属β-内酰胺酶（MBL）EBR变体，即EBR-5。EBR-5与先前已知的EBR-1氨基酸同一性为82.13%。EBR-5在大肠杆菌中的表达降低了对广谱头孢菌素和碳青霉烯类药物的敏感性。与携带[未提及具体内容]的重组菌株相比，携带EBR-5的重组菌株对哌拉西林、头孢噻肟和美罗培南表现出更高的最低抑菌浓度。尽管存在基因多样性，但EBR-5和EBR-1具有相似的动力学参数，除了头孢吡肟、头孢噻肟、头孢西丁、头孢噻吩和美罗培南，EBR-5对它们的水解作用更强。除了[未提及具体内容]，对SCVM0123的全基因组测序分析还揭示了一个质粒介导的[未提及具体基因名称]基因。这项研究强调了[未提及具体监测对象]监测的重要性，因为它可能是这些β-内酰胺酶基因的潜在储存库。碳青霉烯酶是临床治疗面临的最大威胁之一，因为它们可以通过水解碳青霉烯类药物和其他β-内酰胺类抗菌药物而赋予耐药性。在本研究中，我们在粪便埃氏菌中鉴定出一种新的金属β-内酰胺酶EBR变体，即EBR-5。报道了EBR-5的生化特性、底物水解能力和抑制谱。通过全基因组测序和生物信息学分析，我们首次揭示ESBL基因[未提及具体基因名称]位于一个质粒上。这项研究扩展了B类金属β-内酰胺酶的数据库。同时，[未提及具体内容]可能是[未提及具体内容]和[未提及具体内容]的主要储存库，它们有可能传播到病原体中。
