PDF(Pubmed)
Abstract：
UNASSIGNED: This research aims to profile ten novel strains of carbapenem-resistant Enterobacteriaceae (CRE) co-carrying blaKPC and blaNDM.
UNASSIGNED: Clinical CRE strains, along with corresponding medical records, were gathered. To ascertain the susceptibility of the strains to antibiotics, antimicrobial susceptibility tests were conducted. To validate the transferability and cost of fitness of plasmids, conjugation experiments and growth curves were employed. For determining the similarity between different strains, ERIC-PCR was utilised. Meanwhile, whole genome sequencing (WGS) was performed to characterise the features of plasmids and their evolutionary characteristics.
UNASSIGNED: During the course of this research, ten clinical CRE strains co-carrying blaKPC and blaNDM were gathered. It was discovered that five out of these ten strains exhibited resistance to tigecycline. A closer examination of the mechanisms underlying tigecycline resistance revealed that tmexCD1-toprJ1, blaKPC-2, and blaNDM-1 existed concurrently within a single Citrobacter freundii strain (CF10). This strain, with a minimum inhibitory concentration (MIC) of 32 mg/L to tigecycline, was obtained from a sepsis patient. Furthermore, an investigation of genome evolution implied that CF10 belonged to a novel ST type 696, which lacked analogous strains. Aligning plasmids exposed that similar plasmids all had less than 70% coverage when compared to pCF10-tmexCD1, pCF10-KPC, and pCF10-NDM. It was also found that tmexCD1-toprJ1, blaKPC-2, and blaNDM-1 were transferred by Tn5393, IS5, and Tn6296, respectively.
UNASSIGNED: This research presents the first report of coexistence of tmexCD1-toprJ1, blaKPC-2, and blaNDM-1 in a carbapenem and tigecycline-resistant C. freundii strain, CF10.
UNASSIGNED: Tigecycline is considered a \"last resort\" antibiotic for treating CRE infections. The ongoing evolution of resistance mechanisms to both carbapenem and tigecycline presents an alarming situation. Moreover, the repeated reporting of both these resistance mechanisms within a single strain poses a significant risk to public health. The research revealed that the genes tmexCD1-toprJ1, blaKPC-2, and blaNDM-1, which cause carbapenem and tigecycline-resistance in the same strain, were located on mobile elements, suggesting a potential for horizontal transmission to other Gram-negative bacteria. The emergence of such a multi-resistant strain within hospitals should raise significant concern due to the scarcity of effective antimicrobial treatments for these \"superbugs\".
UNASSIGNED: Clinical CRE strains, along with corresponding medical records, were gathered. To ascertain the susceptibility of the strains to antibiotics, antimicrobial susceptibility tests were conducted. To validate the transferability and cost of fitness of plasmids, conjugation experiments and growth curves were employed. For determining the similarity between different strains, ERIC-PCR was utilised. Meanwhile, whole genome sequencing (WGS) was performed to characterise the features of plasmids and their evolutionary characteristics.
UNASSIGNED: During the course of this research, ten clinical CRE strains co-carrying blaKPC and blaNDM were gathered. It was discovered that five out of these ten strains exhibited resistance to tigecycline. A closer examination of the mechanisms underlying tigecycline resistance revealed that tmexCD1-toprJ1, blaKPC-2, and blaNDM-1 existed concurrently within a single Citrobacter freundii strain (CF10). This strain, with a minimum inhibitory concentration (MIC) of 32 mg/L to tigecycline, was obtained from a sepsis patient. Furthermore, an investigation of genome evolution implied that CF10 belonged to a novel ST type 696, which lacked analogous strains. Aligning plasmids exposed that similar plasmids all had less than 70% coverage when compared to pCF10-tmexCD1, pCF10-KPC, and pCF10-NDM. It was also found that tmexCD1-toprJ1, blaKPC-2, and blaNDM-1 were transferred by Tn5393, IS5, and Tn6296, respectively.
UNASSIGNED: This research presents the first report of coexistence of tmexCD1-toprJ1, blaKPC-2, and blaNDM-1 in a carbapenem and tigecycline-resistant C. freundii strain, CF10.
UNASSIGNED: Tigecycline is considered a \"last resort\" antibiotic for treating CRE infections. The ongoing evolution of resistance mechanisms to both carbapenem and tigecycline presents an alarming situation. Moreover, the repeated reporting of both these resistance mechanisms within a single strain poses a significant risk to public health. The research revealed that the genes tmexCD1-toprJ1, blaKPC-2, and blaNDM-1, which cause carbapenem and tigecycline-resistance in the same strain, were located on mobile elements, suggesting a potential for horizontal transmission to other Gram-negative bacteria. The emergence of such a multi-resistant strain within hospitals should raise significant concern due to the scarcity of effective antimicrobial treatments for these \"superbugs\".
摘要：
■这项研究旨在分析十种新型的碳青霉烯抗性肠杆菌科（CRE）菌株，这些菌株共同携带blaKPC和blaNDM。
■临床CRE菌株，还有相应的医疗记录,是聚集的。为了确定菌株对抗生素的敏感性，进行了抗菌药物敏感性试验。为了验证质粒的可转移性和适应性成本，采用缀合实验和生长曲线。为了确定不同菌株之间的相似性，使用ERIC-PCR。同时,进行全基因组测序(WGS)以表征质粒的特征及其进化特征.
■在本研究过程中，收集了10株共同携带blaKPC和blaNDM的临床CRE菌株。发现这10个菌株中有5个表现出对替加环素的抗性。对替加环素耐药性的潜在机制的仔细检查表明，tmexCD1-toprJ1，blaKPC-2和blaNDM-1同时存在于单一的弗氏柠檬酸杆菌菌株（CF10）中。这个菌株,对替加环素的最小抑制浓度（MIC）为32mg/L，是从脓毒症患者那里获得的。此外，对基因组进化的研究表明，CF10属于新型ST型696，缺乏类似的菌株。与pCF10-tmexCD1，pCF10-KPC相比，暴露于相似质粒的比对质粒的覆盖率均小于70％，和pCF10-NDM。还发现tmexCD1-toprJ1、blaKPC-2和blaNDM-1分别通过Tn5393、IS5和Tn6296转移。
■这项研究首次报道了tmexCD1-toprJ1，blaKPC-2和blaNDM-1在耐碳青霉烯类和替加环素的品系中共存。CF10.
替加环素被认为是治疗CRE感染的“最后手段”抗生素。对碳青霉烯类和替加环素的耐药机制的持续发展提出了令人震惊的情况。此外，在单一菌株中重复报告这两种耐药机制对公众健康构成重大风险.研究表明，在同一菌株中引起碳青霉烯类和替加环素抗性的基因tmexCD1-toprJ1，blaKPC-2和blaNDM-1，位于移动元素上，提示水平传播给其他革兰氏阴性细菌的可能性。由于这些“超级细菌”缺乏有效的抗菌治疗，医院内这种多重耐药菌株的出现应该引起人们的关注。
■临床CRE菌株，还有相应的医疗记录,是聚集的。为了确定菌株对抗生素的敏感性，进行了抗菌药物敏感性试验。为了验证质粒的可转移性和适应性成本，采用缀合实验和生长曲线。为了确定不同菌株之间的相似性，使用ERIC-PCR。同时,进行全基因组测序(WGS)以表征质粒的特征及其进化特征.
■在本研究过程中，收集了10株共同携带blaKPC和blaNDM的临床CRE菌株。发现这10个菌株中有5个表现出对替加环素的抗性。对替加环素耐药性的潜在机制的仔细检查表明，tmexCD1-toprJ1，blaKPC-2和blaNDM-1同时存在于单一的弗氏柠檬酸杆菌菌株（CF10）中。这个菌株,对替加环素的最小抑制浓度（MIC）为32mg/L，是从脓毒症患者那里获得的。此外，对基因组进化的研究表明，CF10属于新型ST型696，缺乏类似的菌株。与pCF10-tmexCD1，pCF10-KPC相比，暴露于相似质粒的比对质粒的覆盖率均小于70％，和pCF10-NDM。还发现tmexCD1-toprJ1、blaKPC-2和blaNDM-1分别通过Tn5393、IS5和Tn6296转移。
■这项研究首次报道了tmexCD1-toprJ1，blaKPC-2和blaNDM-1在耐碳青霉烯类和替加环素的品系中共存。CF10.
替加环素被认为是治疗CRE感染的“最后手段”抗生素。对碳青霉烯类和替加环素的耐药机制的持续发展提出了令人震惊的情况。此外，在单一菌株中重复报告这两种耐药机制对公众健康构成重大风险.研究表明，在同一菌株中引起碳青霉烯类和替加环素抗性的基因tmexCD1-toprJ1，blaKPC-2和blaNDM-1，位于移动元素上，提示水平传播给其他革兰氏阴性细菌的可能性。由于这些“超级细菌”缺乏有效的抗菌治疗，医院内这种多重耐药菌株的出现应该引起人们的关注。
