医院感染阴沟肠杆菌rDNA指纹图分析

Ribosomal DNA Fingerprinting Analysis of Enterobacter Cloacae Isolated from an Outbreak of Nosocomial Infection

应用ＰＣＲ技术从大肠杆菌中分别扩增出１６Ｓ、２３Ｓ核糖体ＲＮＡ基因（ｒＤＮＡ），以［α－￣３２Ｐ］ｄＡＴＰ经缺口平移标记ｒＤＮＡ后作为广谱探针。选用ＨｉｎｄｉＩＩＩ、ＥｃｏＲＩ、ＢｇＩＩ和ＢａｍＨＩ不同内切酶，对医院感染阴沟肠杆菌及环境分离菌进行染色体ｒＤＮＡ指纹图分析。结果：１０名感染患者、显微外科患者和氧气瓶的分离菌指纹图完全相同，对照菌有差异。证明此次医院感染病原菌属同一克隆株，传播途径为消毒不彻底的上氧设施和吸痰器。该法准确、可靠，特异性强、重复性好，为控制和预防医院感染，追踪传染源和传播途径提供了遗传学信息。

6s and 23s ribosomaI DN A(rDNA)gcnes were amplified form E.coli labelled with [α-￣32P]dATP by nick translation,and applied as conserved geneprobes to detecting broad-spectrum rDNA。rDNA fingerprinting analvsis of Enterohacter ctoacae(E. ctoacae) isolated form an outbreak of nosocomial infection and other hospital environmental sources was conducted with digestion by differ-ent restrictive endonuclease, such as Hind III, EcoRI, Bam HI, Bgl I,et al.ResuIts showed rDNA fingerprinting of E. ctoacae strains isolated from 10 patients with nosocomial infeetion was the same as that from other sources.It suggested E. cloacae causing this outbreak was originatd from one genetic clone,and its source of infection was the tubes and humidifying bottles for oxygenation. rDNA fingerprinting technique is accurate, reliable,specific and repeatable,and will plays important roles in identification and classification of bacteria,tracking the source of transmission of nosocomial infection。