Department of Biology, College of Science, Mustansiriyah University, POX 10422, Baghdad, Iraq.
Mol Biol Rep. 2022 Jun;49(6):4653-4658. doi: 10.1007/s11033-022-07314-3. Epub 2022 Apr 26.
The serine carbapenemase enzymes (KPC) which produce from bacteria klebsiella pneumoniae today have been emerged as one of the β-lactamase enzymes that is capable to inactivating the last line of carbapenems. The gene encoding the K. pneumonia (bla) belongs to gene carried on plasmid among Enterobacteriaceae family, which has modulation for the infections control so this study is aimed to spot the presence and evaluate bla gene expression by real-time PCR in local isolates of K. pneumonia.
Forty-seven of K. pneumonia isolates were isolated from different clinical samples (blood, sputum, urine, wounds and burns) from patients in separate hospitals in Baghdad., Antimicrobial sensitivity test was carried out by vitik-2 system and Kirby- Bauer method. The PCR was employed to detect carbapenemase gene.
The results of this study showed that all explored isolates were resistant to Ertapenem, Meropenem and imipenem 47(100%). Phenotypically, all the isolates had carbapenemase which hydrolyzed the carbapenem antibiotics. Furthermore, the isolates showed (100%) resistance to Cefazolin, Ampicillin and Amoxicillin/ Clavulic acid. However, the most effective antibiotic was Levofloxacin (91.5%). The results of conventional PCR technique for the detection of bla gene showed that 38 (80.9%) isolates of carbapenem-resistant K. pneumoniae harboured bla gene (1010 bp), while none carried other carbapenemase genes including bla, bla and bla genes. High levels of carbapenem resistance was clarified by the imipenem and meropenem MICs determination. All 38 isolates were positive in CNPT. Furthermore, the 38 isolates showed over expression of bla gene compared with housekeeping rpo gene in Real-Time PCR.
According to these results, the resistant isolates to carbapenem were belong to the present and high level expression of bla gene in our local isolates.
如今，由肺炎克雷伯菌产生的丝氨酸碳青霉烯酶（KPC）已成为能够使碳青霉烯类药物失活的β-内酰胺酶之一。编码肺炎克雷伯菌（bla）的基因属于肠杆菌科质粒上携带的基因，对感染控制具有调节作用，因此本研究旨在检测bla 基因在当地肺炎克雷伯菌分离株中的存在并通过实时 PCR 进行评估。
从巴格达不同医院的患者的不同临床样本（血液、痰液、尿液、伤口和烧伤）中分离出 47 株肺炎克雷伯菌。采用 Vitik-2 系统和 Kirby-Bauer 方法进行抗生素敏感性试验。采用 PCR 检测碳青霉烯酶基因。
本研究结果表明，所有被研究的分离株均对厄他培南、美罗培南和亚胺培南耐药（100%）。表型上，所有分离株均具有水解碳青霉烯类抗生素的碳青霉烯酶。此外，这些分离株对头孢唑林、氨苄西林和阿莫西林/克拉维酸（100%）均具有耐药性。然而，最有效的抗生素是左氧氟沙星（91.5%）。bla 基因检测的常规 PCR 技术结果显示，38 株（80.9%）耐碳青霉烯类肺炎克雷伯菌携带 bla 基因（1010 bp），而无其他碳青霉烯酶基因，包括 bla、bla 和 bla 基因。通过亚胺培南和美罗培南 MIC 值的测定，明确了碳青霉烯类药物的高耐药性。所有 38 株分离株均在 CNPT 中呈阳性。此外，38 株分离株在实时 PCR 中与管家基因 rpo 相比，bla 基因表达水平升高。
根据这些结果，对碳青霉烯类药物耐药的分离株属于本地区bla 基因的存在和高表达。
