Xu Lei, Yin Min, Zhu Tingyuan, Liu Yabo, Ying Yuanyuan, Lu Junwan, Lin Chaoqing, Ying Jianchao, Xu Teng, Ni Liyan, Bao Qiyu, Lu Shunfei
School of Laboratory Medicine and Life Science/Institute of Biomedical Informatics, Wenzhou Medical University, Wenzhou 325035, China.
School of Medicine, Lishui College, Lishui 323000, China.
Int J Genomics. 2018 May 10;2018:1242819. doi: 10.1155/2018/1242819. eCollection 2018.
, a gram-negative bacterium from the genus and family , is present in various natural environments and considered to be plant endophytes. We isolated the PV989 strain from the clinic and sequenced its whole genome. Besides a chromosome DNA molecule, it also harboured three large plasmids. A comparative genomics analysis was performed for the smallest plasmid, pPV989-94. It can be divided into four regions, including three conservative regions related to replication (R1), transfer conjugation (R2), and transfer leading (R3), and one variable region (R4). Further analysis showed that pPV989-94 is most similar to plasmids LA637P2 and pEA68 of strains isolated from fruit trees. These three plasmids share three conservative regions (R1, R2, and R3). Interestingly, a fragment (R4') in R4, mediated by phage integrase and phage integrase family site-specific recombinase and encoding 9 genes related to glycometabolism, resistance, and DNA repair, was unique in pPV989-94. Homologues of R4' were found in other plasmids or chromosomes, suggesting that horizontal gene transfer (HGT) occurred among different bacteria of various species or genera. The acquired functional genes may play important roles in the adaptation of bacteria to different hosts or environmental conditions.
，一种来自 属和 科的革兰氏阴性菌，存在于各种自然环境中，被认为是植物内生菌。我们从临床分离出PV989菌株并对其全基因组进行了测序。除了一个染色体DNA分子外，它还携带三个大质粒。对最小的质粒pPV989 - 94进行了比较基因组学分析。它可分为四个区域，包括与复制（R1）、转移接合（R2）和转移先导（R3）相关的三个保守区域，以及一个可变区域（R4）。进一步分析表明，pPV989 - 94与从果树分离的 菌株的质粒LA637P2和pEA68最相似。这三个质粒共享三个保守区域（R1、R2和R3）。有趣的是，R4中的一个片段（R4'）由噬菌体整合酶和噬菌体整合酶家族位点特异性重组酶介导，编码9个与糖代谢、抗性和DNA修复相关的基因，在pPV989 - 94中是独特的。在其他质粒或染色体中发现了R4'的同源物，这表明水平基因转移（HGT）发生在不同物种或属的不同细菌之间。获得的功能基因可能在细菌适应不同宿主或环境条件中发挥重要作用。
