發(fā)布者：抗性基因網(wǎng) 時間：2023-06-12 瀏覽量：413
摘要
? ? ? 移動粘菌素耐藥性（mcr）基因在全球的出現(xiàn)和傳播對公眾健康構(gòu)成了重大威脅，因為粘菌素仍然是耐多藥感染的最后一線治療選擇之一。2018年至2020年間，在愛爾蘭采集了環(huán)境樣本（157份水和157份廢水）。使用Brilliance ESBL、Brilliance CRE、mSuperCARBA和含有環(huán)丙沙星圓盤的McConkey瓊脂評估所收集的樣品是否存在抗微生物耐藥性細菌。在培養(yǎng)之前，對所有水和綜合人工濕地進水和出水樣品進行過濾，并在緩沖蛋白胨水中富集，而廢水樣品則直接培養(yǎng)。收集的分離物通過MALDI-TOF進行鑒定，測試對包括粘菌素在內(nèi)的16種抗菌藥物的易感性，隨后進行全基因組測序?？傮w而言，從六個樣本（淡水（n=2）、醫(yī)療機構(gòu)廢水（n=2個）、污水處理廠進水（n=1個）和綜合人工濕地進水（養(yǎng)豬場廢物）（n=1））中回收了八種mcr陽性腸桿菌（一種mcr-8和七種mcr-9）。雖然mcr-8陽性的肺炎克雷伯菌對粘菌素表現(xiàn)出耐藥性，但所有7種攜帶腸桿菌的mcr-9仍然易感。所有分離株都表現(xiàn)出多藥耐藥性，通過全基因組測序分析，發(fā)現(xiàn)其攜帶多種抗微生物耐藥性基因，即30±4.1（10–61），包括碳青霉烯酶、blaOXA-48（n=2）和blaNDM-1（n=1），其中三個分離株攜帶這些基因。mcr基因位于IncHI2、IncFIIK和IncI1樣質(zhì)粒上。這項研究的發(fā)現(xiàn)突出了環(huán)境中mcr基因的潛在來源和庫，并說明需要進一步研究，以更好地了解環(huán)境在抗微生物耐藥性的持久性和傳播中所起的作用。
Abstract
The emergence and dissemination of mobile colistin resistance (mcr) genes across the globe poses a significant threat to public health, as colistin remains one of the last line treatment options for multi-drug resistant infections. Environmental samples (157 water and 157 wastewater) were collected in Ireland between 2018 and 2020. Samples collected were assessed for the presence of antimicrobial resistant bacteria using Brilliance ESBL, Brilliance CRE, mSuperCARBA and McConkey agar containing a ciprofloxacin disc. All water and integrated constructed wetland influent and effluent samples were filtered and enriched in buffered peptone water prior to culture, while wastewater samples were cultured directly. Isolates collected were identified via MALDI-TOF, were tested for susceptibility to 16 antimicrobials, including colistin, and subsequently underwent whole genome sequencing. Overall, eight mcr positive Enterobacterales (one mcr-8 and seven mcr-9) were recovered from six samples (freshwater (n = 2), healthcare facility wastewater (n = 2), wastewater treatment plant influent (n = 1) and integrated constructed wetland influent (piggery farm waste) (n = 1)). While the mcr-8 positive K. pneumoniae displayed resistance to colistin, all seven mcr-9 harbouring Enterobacterales remained susceptible. All isolates demonstrated multi-drug resistance and through whole genome sequencing analysis, were found to harbour a wide variety of antimicrobial resistance genes i.e., 30 ± 4.1 (10–61), including the carbapenemases, blaOXA-48 (n = 2) and blaNDM-1 (n = 1), which were harboured by three of the isolates. The mcr genes were located on IncHI2, IncFIIK and IncI1-like plasmids. The findings of this study highlight potential sources and reservoirs of mcr genes in the environment and illustrate the need for further research to gain a better understanding of the role the environment plays in the persistence and dissemination of antimicrobial resistance.
https://www.sciencedirect.com/science/article/pii/S0048969723012652