摘要
目的 通过大规模测序研究临床分离的大肠埃希菌的质粒基因组所携带的氨基糖苷类耐药基因分布及其多态性.方法 收集4年临床分离非重复的320株大肠埃希菌.菌株分为两个部分,碱裂解法提取全部质粒,Solexa测序获得大规模的短序列.采用比较基因组学和分子进化方法分析两个样本所含的氨基糖苷类耐药基因类型及丰度的差异,研究氨基糖苷类耐药基因存在的核苷酸多态位点.结果 测序法获得两批数据,E1短序列总数为11 077 768,可以定位到参照序列上为71 528（0.646%）.E2短序列总数为9 377 792,可以定位到参照序列上是49 944（0.532%）.两个样本中共有9个氨基糖苷类耐药基因型,strB基因最多,其次是strA、aacC2.两个样本中9个氨基糖苷类耐药基因共发现67个单核苷酸多态性（SNPs）位点,约50%为非同义突变.同一个位点的A、G二核苷酸多态现象常见.结论 此次样本中大肠埃希菌质粒上分布多种氨基糖苷类耐药基因.存在着大量的SNPs.
Objective To investigate the distribution and single nucleotide polymorphism （SNPs） of aminoglycoside antibiotic resistance gene in the plasmids of Escherichia coll. Methods Total 320 clinical strains of Escherichia coil were collected from the First Affiliated Hospital of Wenzhou Medical College, including 160 strains collected from 2002 to 2003 （ E1 ） and another 160 strains collected from 2008 to 2009 （E2）. The plasmids of Escherichia coil were extracted by alkaline lysis method. Solexa/lllumina sequencing technology was used to sequence plasmids, genomes were analyzed by using Solexa Genome Analysis System. Soap programs were used to analysis gene distribution, SNPs and to compare lineage-specific mutations. Results In E1 sequencing, 11,077,768 reads were generated and 0.646% of them mapped to the reference sequences. Whereas in E2, 9,377,792 reads were generated and 0.532% of which mapped to the reference. There were nine aminoglycoside antibiotic resistance genes in the two batches of samples, strB genes were the most frequent, followed by strA, aacC2. A total of 67 SNPs sites dispersed into the two batched of samples. Approximately 50% was non-synonymous mutations. It was interesting that A and G coexistent in one position was the most prevalent polymorphism. Conclusion There are variety of aminoglycoside resistant genes and many single nucleotide polymorphisms in plasmids of Escherichia coll.
出处
《浙江医学》
CAS
2011年第12期1790-1792,共3页
Zhejiang Medical Journal
基金
基金项目：浙江省自然科学基金（Y2110204）
温州市科技计划项目（H201（1[）（）22）
