Objective The prevalence of carbapenem-resistant Klebsiella pneumoniae(CR-KP)is a global public health problem.It is mainly caused by the plasmid-carried carbapenemase gene.Outer membrane vesicles(OMVs)contain toxins ...Objective The prevalence of carbapenem-resistant Klebsiella pneumoniae(CR-KP)is a global public health problem.It is mainly caused by the plasmid-carried carbapenemase gene.Outer membrane vesicles(OMVs)contain toxins and other factors involved in various biological processes,includingβ-lactamase and antibiotic-resistance genes.This study aimed to reveal the transmission mechanism of OMV-mediated drug resistance of Klebsiella(K.)pneumoniae.Methods We selected CR-KP producing K.pneumoniae carbapenemase-2(KPC-2)to study whether they can transfer resistance genes through OMVs.The OMVs of CR-KP were obtained by ultracentrifugation,and incubated with carbapenem-sensitive K.pneumoniae for 4 h.Finally,the carbapenem-sensitive K.pneumoniae was tested for the presence of bla_(KPC-2)resistance gene and its sensitivity to carbapenem antibiotics.Results The existence of OMVs was observed by the electron microscopy.The extracted OMVs had bla_(KPC-2)resistance gene.After incubation with OMVs,bla_(KPC-2)resistance gene was detected in sensitive K.pneumoniae,and it became resistant to imipenem and meropenem.Conclusion This study demonstrated that OMVs isolated from KPC-2-producing CR-KP could deliver bla_(KPC-2)to sensitive K.pneumoniae,allowing the bacteria to produce carbapenemase,which may provide a novel target for innovative therapies in combination with conventional antibiotics for treating carbapenem-resistant Enterobacteriaceae.展开更多
目的评估碳青霉烯类抑制法(carbapenem inactivation method,CIM)和Carba NP对铜绿假单胞菌碳青霉烯酶表型的筛选能力。方法选取河北省医学微生物菌种保藏库(Hebei Provincial Bank for Medical Culture Collections,HBMCC)保存的碳青...目的评估碳青霉烯类抑制法(carbapenem inactivation method,CIM)和Carba NP对铜绿假单胞菌碳青霉烯酶表型的筛选能力。方法选取河北省医学微生物菌种保藏库(Hebei Provincial Bank for Medical Culture Collections,HBMCC)保存的碳青霉烯类耐药铜绿假单胞菌146株,分别用CIM和Carba NP法检测碳青霉烯酶活性,采用PCR方法检测VIM-1、KPC-2、IMP-4、NDM-1基因。结果 146株铜绿假单胞菌中有11株Carba NP阳性,阳性率为7.5%(11/146);13株CIM阳性,阳性率为8.9%(13/146)。9株碳青霉烯酶编码基因阳性,其中6株VIM-1阳性,1株VIM-1和IMP-4同时阳性,2株KPC-2阳性;碳青霉烯酶编码基因阳性的菌株Carba NP和CIM均阳性;5株基因检测阴性菌株中1株仅Carba NP阳性,3株仅CIM阳性,1株Carba NP和CIM均阳性。结论 CIM能够准确快速筛选铜绿假单胞菌碳青霉烯酶活性,是一种经济高效的表型筛选方法。展开更多
基金supported by the National Natural Science Foundation of China(No.31771189)the Wuhan Health Commission(No.WX18C17 and No.WX19Q31)the Natural Science Foundation of Hubei Province,China(No.2017CFA065 and No.WJ2019H378).
文摘Objective The prevalence of carbapenem-resistant Klebsiella pneumoniae(CR-KP)is a global public health problem.It is mainly caused by the plasmid-carried carbapenemase gene.Outer membrane vesicles(OMVs)contain toxins and other factors involved in various biological processes,includingβ-lactamase and antibiotic-resistance genes.This study aimed to reveal the transmission mechanism of OMV-mediated drug resistance of Klebsiella(K.)pneumoniae.Methods We selected CR-KP producing K.pneumoniae carbapenemase-2(KPC-2)to study whether they can transfer resistance genes through OMVs.The OMVs of CR-KP were obtained by ultracentrifugation,and incubated with carbapenem-sensitive K.pneumoniae for 4 h.Finally,the carbapenem-sensitive K.pneumoniae was tested for the presence of bla_(KPC-2)resistance gene and its sensitivity to carbapenem antibiotics.Results The existence of OMVs was observed by the electron microscopy.The extracted OMVs had bla_(KPC-2)resistance gene.After incubation with OMVs,bla_(KPC-2)resistance gene was detected in sensitive K.pneumoniae,and it became resistant to imipenem and meropenem.Conclusion This study demonstrated that OMVs isolated from KPC-2-producing CR-KP could deliver bla_(KPC-2)to sensitive K.pneumoniae,allowing the bacteria to produce carbapenemase,which may provide a novel target for innovative therapies in combination with conventional antibiotics for treating carbapenem-resistant Enterobacteriaceae.
