The complete nucleotide sequence of the resistance plasmid R478: defining the backbone components of incompatibility group H conjugative plasmids through comparative genomics
The complete nucleotide sequence of the resistance plasmid R478: defining the backbone components of incompatibility group H conjugative plasmids through comparative genomics
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DOI：
10.1016/j.plasmid.2004.06.006
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发表时间：
2004-11-01
期刊：
影响因子：
2.6
通讯作者：
Taylor, DE
中科院分区：
文献类型：
--
作者：
Gilmour, MW;Thomson, NR;Taylor, DE
细菌之间的抗性决定因素的水平转移可以通过结合质粒DNA元件实现。我们已经确定了不相容组H （IncH）质粒R478的完整序列，该质粒最初从革兰氏阴性粘质沙雷菌中分离出来。这种可自转移的染色体外遗传元件包含295个预测基因，其中144个与IncH质粒R27和pHCM1的编码序列高度相似。这3种IncH质粒之间的相似性区域主要编码核心质粒决定因子（即复制、分裂和稳定性以及接合转移），我们通过比较分析确定了最小的IncH质粒骨架决定因子。在主干中不包含抗性决定因子，R478特有的大部分序列包含在两个转移区之间的大片连续区域中。这些发现表明，质粒进化主要发生在核心决定因子以外的区域的基因获取/丢失。此外，R478的模块化进化是由基因邻居或操纵子的存在所标志的，这些基因邻居或操纵子与广泛的染色体、转座子和质粒元件的序列高度相关。共轭转移区与编码在SXT、Rts1、pCAR1、R391和pRS241d上的序列最为相似。在R478上编码的双分区模块类似于许多序列；包括pMT1、pCTXM3、pCP301、P1、P7、pB171。R478还编码对四环素（Tn10）、氯霉素（cat）、卡那霉素（aphA）、汞（类似于Tn21）、银（类似于pMG101）、铜（类似于pRJ1004）、砷（类似于pYV）和碲（两个独立的区域，类似于IncH12 ter决定因子和IncP kla决定因子）的抗性。其他r478编码的序列与Tn7、IS26、tus、mucAB和hok相关，其中后者被insLKJ包围，可能参与分离后杀伤。与多种细菌序列的相似性突出了水平转移DNA元素通过细菌基因库获得和传播遗传性状的能力。(C) 2004爱思唯尔公司版权所有。
Horizontal transfer of resistance determinants amongst bacteria can be achieved by conjugative plasmid DNA elements. We have determined the complete 274,762 bp sequence of the incompatibility group H (IncH) plasmid R478, originally isolated from the Gram negative opportunistic pathogen Serratia marcescens. This self-transferable extrachromosomal genetic element contains 295 predicted genes, of which 144 are highly similar to coding sequences of IncH plasmids R27 and pHCM1 The regions of similarity among these three IncH plasmids principally encode core plasmid determinants (i.e., replication, partitioning and stability, and conjugative transfer) and we conducted a comparative analysis to define the minimal IncHI plasmid backbone determinants. No resistance determinants are included in the backbone and most of the sequences unique to R478 were contained in a large contiguous region between the two transfer regions. These findings indicate that plasmid evolution occurs through gene acquisition/loss predominantly in regions outside of the core determinants. Furthermore, a modular evolution for R478 was signified by the presence of gene neighbors or operons that were highly related to sequences from a wide range of chromosomal, transposon, and plasmid elements. The conjugative transfer regions are most similar to sequences encoded on SXT, Rts1, pCAR1, R391, and pRS241d. The dual partitioning modules encoded on R478 resemble numerous sequences; including pMT1, pCTXM3, pCP301, P1, P7,and pB171. R478 also codes for resistance to tetracycline (Tn10), chloramphenicol (cat), kanamycin (aphA), mercury (similar to Tn21), silver (similar to pMG101), copper (similar to pRJ1004), arsenic (similar to pYV), and tellurite (two separate regions similar to IncH12 ter determinants and IncP kla determinants). Other R478-encoded sequences are related to Tn7, IS26, tus, mucAB, and hok, where the latter is surrounded by insLKJ, and could potentially be involved in post-segregation killing. The similarity to a diverse set of bacterial sequences highlights the ability of horizontally transferable DNA elements to acquire and disseminate genetic traits through the bacterial gene pool. (C) 2004 Elsevier Inc. All rights reserved.