应用VNTR分析方法对院内感染铜绿假单胞菌分子分型的研究

目的 探讨以多位点可变数目串联重复序列(VNTR)分析方法行多重耐药铜绿假单胞菌分子分型的效果。方法 选择2015年5月至2017年5月分离自本院13个病区的多重耐药铜绿假单胞菌78株,提取菌株DNA。在铜绿假单胞菌基因组中随机选择8个位点,以VNTR扩增物扩增菌株DNA,产物毛细管电泳。对扩增产物相对分子质量及菌株在不同位点的VNTR重复数进行计算,并实施聚类分析及同源性分析。结果 8个VNTR位点重复基序大小为7～128 bp,多态性指数为0.47～0.89,分布较为均匀;VNTR分析法将78株多重耐药铜绿假单胞菌分为5个群;6例患者不同分离株在8个位点重复数均一致。结论 在铜绿假单胞菌基因分型及溯源研究中VNTR分析法的应用价值高,可为控制院内感染提供依据及技术方法,需引起关注。

VNTR analysis of molecular typing of Pseudomonas aeruginosa in nosocomial infection

Objective To investigate the effect of multi-loci VNTR analysis on molecular typing of multi-drug-resistance pseudomonas aeruginosa.Methods Seventy-eight strains of multi-drug-resistance pseudomonas aeruginosa were isolated from 13 departments of our hospital from May 2015 to May 2017,and their DNA was extracted.Eight sites of pseudomonas aeruginosa were randomly selected from the genome of pseudomonas aeruginosa,and the DNA was amplified by VNTR amplification.The products were extracted by capillary electrophoresis.The relative molecular mass of the amplified product and the number of VNTR repeats at different sites of the strain were calculated.Multidrug-resistant pseudomonas aeruginosa was subjected to cluster analysis and homology analysis based on the relative molecular mass of the amplified product and the number of VNTR repeats at different sites.Results The repeat base sequence size of 8 VNTR sites was 7-128 bp,the polymorphism index was 0.47-0.89,and the distribution was relatively uniform.VNTR analysis was applied to divide 78 multi-drug-resistance pseudomonas aeruginosa into 5 groups.In 6 patients,the repeat number of different isolates was the same at 8 sites.Conclusion VNTR analysis method has high application value in the genotyping study and the control of epidemic tracing of pseudomonas aeruginosa. It can provide a basis and technical method for the control of nosocomial infection, which requires high attention.