The genetic diversity of Vibrio anguillarum pJM1-like plasmids was investigated. Plasmids were isolated from 18 V. anguillarum serovar O1 strains collected from different geographic locations and fish species. The plasmids were sequenced and compared with the complete sequence of the published virulence plasmid pJM1. All 18 strains contained pJM1-like plasmids with approximately 65 kbp and all plasmids encoded the virulence genes responsible for the anguibactin iron sequestering system. The plasmids were highly conserved but minor differences were observed in some genes. A single nucleotide polymorphisms (SNPs) analysis showed 0-11 nucleotide variations between each of the 18 plasmids and the pJM1 plasmid. Compared with the sequence of pJM1, nonsynonymous SNPs were identified in fatC, angR, angL, pJM1_p19, and angE. In particular, a mutation found in 15 out of 18 sequenced plasmids in angR has previously been linked to hyperproduction of anguibactin and was found in all the European isolates. However, overall the pJM1-like plasmids isolated from V. anguillarum serovar O1 exhibited a high degree of conservation regardless of their geographical origin or fish species.

中文翻译：

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不同鱼类不同产地鳗鱼弧菌质粒序列分析

研究了鳗弧菌 pJM1 样质粒的遗传多样性。从从不同地理位置和鱼类物种收集的 18 V. anguillarum 血清型 O1 菌株中分离出质粒。对质粒进行测序并与已公布的毒力质粒 pJM1 的完整序列进行比较。所有 18 株都含有 pJM1 样质粒，大约 65 kbp，所有质粒都编码负责 Anguibactin 铁螯合系统的毒力基因。质粒高度保守，但在某些基因中观察到微小差异。单核苷酸多态性 (SNP) 分析显示 18 个质粒和 pJM1 质粒中的每一个之间存在 0-11 个核苷酸变异。与 pJM1 的序列相比，在 fatC、angR、angL、pJM1_p19 和 angE 中发现了非同义 SNP。特别是，在 angR 中 18 个已测序质粒中的 15 个中发现的突变先前已与 anguibactin 的过度生产有关，并在所有欧洲分离株中发现。然而，总体而言，从鳗鲡血清型 O1 中分离的 pJM1 样质粒表现出高度的保护性，无论其地理来源或鱼类种类如何。