两株亚胺培南中介奇异变形杆菌耐药性及基因组测序分析

Analyzing the Molecular Characteristics and Drug Susceptibility of two Imipenem-Intermediate Proteus Mirabilis by Whole Genome Sequencing

目的:对我院分离的两株亚胺培南中介奇异变形杆菌进行全基因组测序并分析其耐药特征。方法:选取两株亚胺培南中介奇异变形杆菌(II-PMI,Imipenem-Intermediate Proteusmirabilis)。按照CLSI2020年公布的药敏方法和药物折点进行药敏实验,应用vitek-2compact及配套GN13(梅里埃,法国)革兰氏阴性菌药敏卡片,进行药敏检测。菌株经质谱仪鉴定后应用试剂盒提取基因组DNA,并应用Ilumina测序平台进行测序。下机数据应用SPAdes3.9.0进行基因组拼接。抗菌药物耐药基因(ARGs)应用Abricate0.8的Card数据库预测,并以plasmid Finder数据库对细菌携带质粒类型进行预测。结果:2014年-2021年各选取一株I-PMI菌株,均来自中老年病人,病人均具有基础疾病。2014年分离的II-PMI菌株对临床常用药物具有较高的耐药性,2021年分离的菌株除亚胺培南中介外,其他药物均为敏感。2014年分离的II-PMI菌株检测到19种耐药相关基因,2021年菌株检测到2种耐药相关基因。两株菌均预测到了Col3M_1型质粒。结论:两株菌耐药及耐药基因携带情况有较大差异,两株菌携带的耐药基因与相应临床常用药物的药敏表型具有较高的一致性。加强耐药和分子流行病学监测与研究有利于明确细菌的耐药性机制,进而为控制细菌耐药性及院内感染传播。

Objective:To characterize the mechanism underlying imipenem nonsusceptibility of two Proteus mirabilis strains isolated from our hospital by Whole genome sequencing(WGS).Method:Two strains of Imipenem-Intermediate Proteus mirabilis(II-PMI)were selected.The drug susceptibility test was carried out and susceptibility was explained by CLSI in 2020.The drug susceptibility test was performed using the vitek-2 compact and the supporting GN13(Merieux,France)Gram-negative bacteria drug susceptibility card.After the strains were identified by mass spectrometer,the genomic DNA was extracted and sequenced by the Illumina sequencing platform.Genome assembly was performed using SPAdes 3.9.0 for sequencing data.Antimicrobial resistance genes(ARGs)were predicted using the Card database of Abricate O0.8,and the plasmid types were predicted using the Plasmid Finder database.Results:One II-PMI strain was selected in 2014 and one in 2021,all of which were from middle-aged and elderly patients with underlying diseases.The II-PMI strain isolated in 2014 had high resistance to commonly used clinical drugs,and the strain isolated in 2021 was sensitive to other drugs except imipenem.Nineteen drug resistance-related genes were detected in the II-PMI strain isolated in 2014,and two drug resistance-related genes were detected in the 2021 strain.Col3M_1 type plasmids were predicted for both strains.Conclusion:The drug resistance and drug resistance genes carried by the two strains were quite different.The drug resistance genes carried by the two strains were highly consistent with the drug susceptibility phenotypes of the corresponding commonly used clinical drugs.Strengthening drug resistance and molecular epidemiological monitoring and research is conducive to clarify the mechanism of bacterial drug resistance,thereby controlling bacterial drug resistance and the spread of nosocomial infections.