Evidence for a symbiosis island involved in horizontal acquisition of pederin biosynthetic capabilities by the bacterial symbiont of Paederus fuscipes beetles
Evidence for a symbiosis island involved in horizontal acquisition of pederin biosynthetic capabilities by the bacterial symbiont of Paederus fuscipes beetles
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DOI：
10.1128/jb.186.5.1280-1286.2004
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发表时间：
2004-03-01
影响因子：
3.2
通讯作者：
Hui, DQ
中科院分区：
文献类型：
--
作者：
Piel, J;Höfer, I;Hui, DQ
Pederin属于一组在陆生甲虫和海洋海绵中发现的抗肿瘤化合物。它显然被所有的甲虫属（Paederus和Paederidus）的成员用作对抗捕食者的化学防御。然而，最近对推测的pederin生物合成（ped）基因簇的分析强烈表明，pederin是由细菌共生体产生的。我们已经对共生体基因组的一个扩展区域进行了测序，以进一步了解这种尚未培养的细菌的生物学和pederin共生的进化。我们的数据表明，该共生体是铜绿假单胞菌的近亲，铜绿假单胞菌通过水平基因转移获得了几种外源遗传元件。除了一个功能性的碲抗性操纵子外，该区域还包含一个全长71.6 kb的基因组岛，其中包含假定的pederin生物合成基因。几个衰减的插入序列元件和岛屿的马赛克样外观表明，ped共生基因的获得之后是进一步的插入和重排。保护物质生物合成基因的水平转移可以解释菊醛类化合物在不同栖息地的无亲缘关系动物中广泛存在的原因。
Pederin belongs to a group of antitumor compounds found in terrestrial beetles and marine sponges. It is used by apparently all members of the rove beetle genera Paederus and Paederidus as a chemical defense against predators. However, a recent analysis of the putative pederin biosynthesis (ped) gene cluster strongly suggests that pederin is produced by bacterial symbionts. We have sequenced an extended region of the symbiont genome to gain further insight into the biology of this as-yet-unculturable bacterium and the evolution of pederin symbiosis. Our data indicate that the symbiont is a very close relative of Pseudomonas aeruginosa that has acquired several foreign genetic elements by horizontal gene transfer. Besides one functional tellurite resistance operon, the region contains a genomic island spanning 71.6 kb that harbors the putative pederin biosynthetic genes. Several decayed insertion sequence elements and the mosaic-like appearance of the island suggest that the acquisition of the ped symbiosis genes was followed by further insertions and rearrangements. A horizontal transfer of genes for the biosynthesis of protective substances could explain the widespread occurrence of pederin-type compounds in unrelated animals from diverse habitats.