Parallel Evolution and Horizontal Gene Transfer of the pst Operon in Firmicutes from Oligotrophic Environments.
Parallel Evolution and Horizontal Gene Transfer of the pst Operon in Firmicutes from Oligotrophic Environments.
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DOI：
10.4061/2011/781642
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发表时间：
2011-03-03
期刊：
影响因子：
--
通讯作者：
Souza V
中科院分区：
文献类型：
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作者：
Moreno-Letelier A;Olmedo G;Eguiarte LE;Martinez-Castilla L;Souza V
高亲和力磷酸盐转运系统（pst）对于贫营养环境中的磷酸盐摄取至关重要。库阿特罗谢内加斯盆地（CCB）的磷含量极低，其特有的芽孢杆菌与贫营养海洋厚壁菌门密切相关。因此，我们预期CCB的pst操纵子与海洋厚壁菌门具有相同的进化历史和蛋白质相似性。在55个厚壁菌门基因组和13个外类群中搜索了pst操纵子的直系同源物。使用最大似然法对pst操纵子和14个串联的看家基因进行了系统发育重建。还分析了磷酸盐结合蛋白（PstS）的保守结构域和三维结构。厚壁菌门的pst操纵子显示出两个高度分化的分支，与栖息地类型无关，也没有系统发育一致性，这表明存在水平基因转移。尽管序列存在差异，但PstS蛋白具有相似的三维结构，这可能是由于水平基因转移事件后的平行进化。
The high affinity phosphate transport system (pst) is crucial for phosphate uptake in oligotrophic environments. Cuatro Cienegas Basin (CCB) has extremely low P levels and its endemic Bacillus are closely related to oligotrophic marine Firmicutes. Thus, we expected the pst operon of CCB to share the same evolutionary history and protein similarity to marine Firmicutes. Orthologs of the pst operon were searched in 55 genomes of Firmicutes and 13 outgroups. Phylogenetic reconstructions were performed for the pst operon and 14 concatenated housekeeping genes using maximum likelihood methods. Conserved domains and 3D structures of the phosphate-binding protein (PstS) were also analyzed. The pst operon of Firmicutes shows two highly divergent clades with no correlation to the type of habitat nor a phylogenetic congruence, suggesting horizontal gene transfer. Despite sequence divergence, the PstS protein had a similar 3D structure, which could be due to parallel evolution after horizontal gene transfer events.