Department of Biology, College of Sciences, University of Hafar Al-Batin (UHB), City Hafr Al Batin, Saudi Arabia.
Water and Food Control Lab, National Center of Salmonella, Shigella, Vibrio-Enteropathogens - Institut Pasteur de Tunis (IPT) Tunis-Belvédère, Tunis, Tunisia.
J Appl Microbiol. 2022 Jan;132(1):279-289. doi: 10.1111/jam.15211. Epub 2021 Jul 27.
Molecular characterization of extended-spectrum β-lactamases (ESBLs) among Salmonella Kentucky and Typhimurium isolates: partial sequence analysis of the types of β-lactamases found in these isolates, clonality, resistance and supposed emergence of ESBL-producing strains.
A retrospective study surveyed the ESBLs occurring in a total of 1404 Salmonella Kentucky and Typhimurium isolates collected over a 5-year period in Tunisia. Antimicrobial susceptibility tests, ESBL phenotype determination (double-disc synergy) were performed. Polymerase chain reaction assays were used for the detection of β-lactamase genes (bla , bla , bla and bla ), class 1 and class 2 integrases (intI1 and intI2) and the 3' conserved segment (3'-CS) of class 1 integron (qacEΔ1+sul1). Sequencing of amplicons of β-lactamase genes was performed. Percentage of 9.8 of the isolates (S. Kentucky = 117, S. Typhimurium = 20) were either resistant to penicillin and had decreased susceptibility to cefotaxime or had a positive double-disc synergy test result. Polymerase chain reaction detected that these isolates harboured one or more β-lactamase genes (bla , bla , bla or bla ). TEM-1, TEM-34, CTX-M15, CTX-M9 and CTX-M61 type ESBLs were identified through sequencing. The novel Salmonella cefotaxime-hydrolysing β-lactamase, CTX-M61/TEM-34, detected in this study showed the emergence of new CTX-M-type ESBLs in Tunisia. There were found 33 different multidrug resistance (MDR) patterns.
These findings highlighted the proliferation of ESBLs and MDR in Salmonella Kentucky and Typhimurium isolates from numerous regions and sources in Tunisia, indicating an emerging public health concern.
For the first time CTX-M-61/TEM-34, a novel cefotaxime-hydrolysing β-lactamase of Salmonella had been detected.
对肯塔基州沙门氏菌和肠炎沙门氏菌分离株中的扩展谱β-内酰胺酶(ESBL)进行分子特征分析:对这些分离株中发现的β-内酰胺酶类型、克隆性、耐药性和可能产生 ESBL 菌株进行部分序列分析。
对突尼斯在过去 5 年中收集的总共 1404 株肯塔基州沙门氏菌和肠炎沙门氏菌分离株进行了一项回顾性研究,检测了这些分离株中存在的 ESBL。进行了抗生素敏感性测试、ESBL 表型测定(双碟协同试验)。聚合酶链反应检测用于检测β-内酰胺酶基因(blaCTX-M15、blaCTX-M9、blaTEM-1 和 blaTEM-34)、I 类和 II 类整合酶(intI1 和 intI2)以及 I 类整合子的 3'保守片段(3'-CS)(qacEΔ1+sul1)。对β-内酰胺酶基因的扩增子进行测序。9.8%的分离株(肯塔基州沙门氏菌=117,肠炎沙门氏菌=20)对青霉素耐药,对头孢噻肟的敏感性降低或双碟协同试验阳性。聚合酶链反应检测到这些分离株携带一种或多种β-内酰胺酶基因(blaCTX-M15、blaCTX-M9、blaTEM-1 或 blaTEM-34)。通过测序鉴定出 TEM-1、TEM-34、CTX-M15、CTX-M9 和 CTX-M61 型 ESBL。在本研究中检测到的新型头孢噻肟水解β-内酰胺酶 CTX-M61/TEM-34 表明新的 CTX-M 型 ESBL 在突尼斯出现。发现了 33 种不同的多药耐药(MDR)模式。
这些发现强调了 ESBL 和 MDR 在来自突尼斯多个地区和来源的肯塔基州沙门氏菌和肠炎沙门氏菌分离株中的扩散,表明这是一个新出现的公共卫生问题。
首次检测到沙门氏菌头孢噻肟水解β-内酰胺酶 CTX-M-61/TEM-34。