摘要
目的:筛选幽门螺杆菌(Hp)对甲硝唑耐药相关基因片段。方法:以5株临床分离的耐药株作为被检菌,1株敏感株作为参考菌,采用抑制差减杂交技术进行基因组差异研究,获取Hp对甲硝唑耐药相关的基因片段,并以斑点杂交方法对所获的基因片段进行了杂交鉴定。结果:在获得的差减阳性克隆中,经斑点杂交筛选后共有37个基因片段的拷贝数在耐药和敏感菌株中存在差异(2倍以上),而其中17个片段其拷贝数存在明显差异(3倍以上)。对以上17个差异片段进行单向测序,根据最高同源性比对结果,分别代表二肽ABC载体渗透酶(dppB)、二肽ABC载体结合蛋白(dppA)等10个基因的同源基因片段在耐药株中存在高拷贝数。结论:所获得的10个差异基因片段可能与幽门螺杆菌对甲硝唑耐药相关。
Objective: To screen metronidazole (MTZ) -resistance associated gene fragments of Helicobacter pylori (H. pylori) by suppression subtractive hybridization (SSH). Methods: The suppression subtractive hybridization (SSH) was used to screen the different DNA fragments between MTZ-resistant and -susceptible clinical strains of H. pylori. The resistant strains specific gene fragments were obtained by SSH and identified by dot blotting. Results: Among the 120 subtractive colonies which were randomly chosen, 37 DNA fragments were different (≥2 times) in DNA-copy numbers between resistant and susceptible strains and 17 of them were significantly different (≥3 times). These 17 DNA fragments were sequenced subsequently. Ten of them were new sequences and the other 7 were duplicated sequences. These sequences represented respectively :depeptide ABC transporter periplasmic dipeptide-binding protein (dppA), permease protein (dppB),et al. Conclusion: Gene fragments specific to MTZ-resistant H. pylori strains were obtained by SSH and these genes may associated with MTZ-resistance of H. pylori.
出处
《浙江大学学报(医学版)》
CAS
CSCD
2007年第5期465-469,共5页
Journal of Zhejiang University(Medical Sciences)
基金
浙江省自然科学基金资助(N29801)