Mitra Shravani, Naha Sharmi, Chakraborty Joy, De Subhadeep, Kaur Harpreet, Majumdar Tapan, Basu Sulagna
Division of Bacteriology, ICMR-National Institute for Research in Bacterial Infections (Formerly ICMR-NICED), Kolkata, West Bengal, India.
Department of Microbiology, Agartala Government Medical College & G B Pant Hospital, Agartala, Tripura, India.
Front Microbiol. 2025 May 22;16:1543427. doi: 10.3389/fmicb.2025.1543427. eCollection 2025.
Mobile genetic elements (MGEs) play a crucial role in the spread of carbapenem resistance. A study was undertaken to characterize MGEs and evaluate their contribution to the spread of carbapenem resistance in and collected from three intensive care units (ICUs) of a tertiary care hospital in Tripura.
Isolates were subjected to susceptibility testing, genotypic detection of carbapenemases and their transmissibility, whole-genome sequencing (WGS), and phylogenomic analysis.
and were the dominant Enterobacterales, exhibiting resistance to the majority of antibiotics. WGS of carbapenemase-producing ( = 15/48,31%) and ( = 13/26,50%) revealed the presence of ( = 21), ( = 1), and ( = 8). Isolates were diverse and belonged to different sequence types, including epidemic clones (-ST16/101/147/231; -ST167/410/648). This study has noted the allelic shift of to similar to global reports. -bearing plasmids were conjugative but those carrying and were non-conjugative. were present in diverse replicons: IncF-types (predominant), IncHI1B, IncX3, and IncX4, etc., while were present in ColKP3, corroborating with global studies. was associated with intact/truncated IS in Tn, with IS, with IS, and IS in Tnb, and with ∆IS in Tn, depicting an ancestral genetic context noted globally. Study isolates were related to other Indian isolates, primarily from blood.
The association with different MGEs noted in the study is similar to those in other parts of India and the globe, signifying that the genetic determinants are part of the global gene pool. These associations can facilitate the spread of carbapenem resistance, leading to outbreaks and treatment failures.
移动遗传元件（MGEs）在碳青霉烯类耐药性传播中起关键作用。本研究旨在对从特里普拉邦一家三级医院的三个重症监护病房（ICU）分离出的肠杆菌科细菌中的MGEs进行特征分析，并评估它们对碳青霉烯类耐药性传播的作用。
对分离菌株进行药敏试验、碳青霉烯酶的基因型检测及其传播性检测、全基因组测序（WGS）和系统基因组分析。
肺炎克雷伯菌和大肠埃希菌是主要的肠杆菌科细菌，对大多数抗生素耐药。对产碳青霉烯酶的肺炎克雷伯菌（15/48，31%）和大肠埃希菌（13/26，50%）进行WGS分析，发现存在blaKPC（21株）、blaNDM（1株）和blaCTX-M（8株）。分离菌株具有多样性，属于不同的序列类型，包括流行克隆（肺炎克雷伯菌-ST16/101/147/231；大肠埃希菌-ST167/410/648）。本研究注意到blaKPC向blaNDM的等位基因转变，与全球报道相似。携带blaKPC的质粒具有接合性，但携带blaNDM和blaCTX-M的质粒不具有接合性。blaKPC存在于多种复制子中：IncF型（占主导）、IncHI1B、IncX3和IncX4等，而blaNDM存在于ColKP3中，这与全球研究结果一致。blaKPC与Tn6296中的完整/截断ISKpn26相关，blaNDM与IS26相关，blaCTX-M与IS26相关，Tn1721中的IS903b以及blaSHV与Tn3中的∆IS相关，描绘了全球范围内常见的祖先遗传背景。研究中的分离菌株与其他印度分离菌株相关，主要来自血液。
本研究中观察到的与不同MGEs的关联与印度其他地区和全球的情况相似，这表明这些遗传决定因素是全球基因库的一部分。这些关联可促进碳青霉烯类耐药性的传播，导致暴发和治疗失败。
