肖桃, 鲁炳怀, 代航, 蔡红艳, 黄振洲, 王多春. 一株同时携带SGI1和SXT/R391耐药基因岛的奇异变形杆菌[J]. 疾病监测, 2019, 34(7): 614-620. DOI: 10.3784/j.issn.1003-9961.2019.07.009
引用本文: 肖桃, 鲁炳怀, 代航, 蔡红艳, 黄振洲, 王多春. 一株同时携带SGI1和SXT/R391耐药基因岛的奇异变形杆菌[J]. 疾病监测, 2019, 34(7): 614-620. DOI: 10.3784/j.issn.1003-9961.2019.07.009
Tao Xiao, Binghuai Lu, Hang Dai, Hongyan Cai, Zhenzhou Huang, Duochun Wang. Genomic context of a Proteus mirabilis strain carrying both SGI1 and SXT/R391 resistance genomic islands[J]. Disease Surveillance, 2019, 34(7): 614-620. DOI: 10.3784/j.issn.1003-9961.2019.07.009
Citation: Tao Xiao, Binghuai Lu, Hang Dai, Hongyan Cai, Zhenzhou Huang, Duochun Wang. Genomic context of a Proteus mirabilis strain carrying both SGI1 and SXT/R391 resistance genomic islands[J]. Disease Surveillance, 2019, 34(7): 614-620. DOI: 10.3784/j.issn.1003-9961.2019.07.009

一株同时携带SGI1和SXT/R391耐药基因岛的奇异变形杆菌

Genomic context of a Proteus mirabilis strain carrying both SGI1 and SXT/R391 resistance genomic islands

  • 摘要:
    目的分析1株人源奇异变形杆菌CA151922的2个耐药相关基因岛SGI1和SXT/R391的基因结构和耐药基因。
    方法聚合酶链式反应(PCR)检测SGI1和SXT/R391基因岛特异性整合酶基因,采用二代测序方法测定CA151922基因组。 分别以SGI1和SXT/R391基因岛的参考序列,从基因组序列中提取基因岛片段并组装。 在线预测并注释开放读码框(ORFs)。 基因岛的同源序列通过在线工具BLASTn获得,采用cd-hit获得非冗余的同源基因,利用R语言构建同源基因的聚类进化关系树。 利用微量肉汤稀释法进行耐药表型检测。
    结果奇异变形杆菌CA151922同时含有SGI1(SGI1-B)和SXT/R391(ICEPmiJpn1)2个耐药相关基因岛。 SGI1-B和ICEPmiJpn1与已知序列相似性分别为97% ~ 99%和96% ~ 99%。 SGI1-B和ICEPmiJpn1携带的耐药基因种类有所差异,但两者携带不同的编码β-内酰胺酶的基因。CA151922为多耐药菌株,耐药达18种,与基因岛耐药基因有关的耐药表型为氨苄西林和磺胺类药物,提示菌株耐药表型不完全由该耐药岛内的耐药基因决定。
    结论首次在奇异变形杆菌中发现,同时携带SGI1和SXT/R391耐药相关基因岛, 增加了菌株耐药的复杂性和严重性,提示应加强对多耐药菌株耐药相关基因岛的监测。

     

    Abstract:
    ObjectiveTo characterize the gene structure and resistance genes of two resistance-related genomic islands (SGI1 and SXT/R391) of a Proteus mirabilis strain (CA151922) isolated from a patient.
    MethodsPolymerase chain reaction (PCR) was conducted to detect the specific integrase gene of SGI1 and SXT/R391, respectively. Next-generation sequencing was performed for the strain CA151922. The contigs of SGI1 and SXT/R391 were extracted and assembled from the whole sequenced genomes against each reference. Online predicting and annotating open reading frames (ORFs) were conducted. Each sequence was used in a BLASTn tool to obtain high homology variants in public database. Non-redundant homologous gene set was identified by cd-hit, a cluster of homologous tree was built by using R 3.4.4. Resistance phenotype was detected with micro-broth dilution method.
    ResultsProteus mirabilis strain CA151922 carried two resistance-related genomic islands, i.e. SGI1 (SGI1-B) and SXT/R391 (ICEPmiJpn1). Compared with known variants of SGI1-B and ICEPmiJpn1, the sequence identity ranged from 97% to 99% and from 96% to 99%, respectively. Compared with each classic sequence, different resistance gene(s) were found, however, SGI1-B and ICEPmiJpn1 harbored different β-lactamase genes. Strain CA151922 was multi-drug resistant to eighteen antibiotics, only ampicillin and sulfonamides were related to the resistance genes on genomic islands, which suggested that resistance phenotype were not all encoded by genes at genomic island.
    ConclusionBoth SGI1 and SXT/R391 resistance-related genomic islands were identified for the first time in a strain of P. mirabilis, which increased the complexity and severity of drug resistance. Surveillance for resistance-related genomic islands in multi-drug resistant strains should be strengthened.

     

/

返回文章
返回