Evidence that plant-like genes in Chlamydia species reflect an ancestral relationship between Chlamydiaceae, cyanobacteria, and the chloroplast
Evidence that plant-like genes in Chlamydia species reflect an ancestral relationship between Chlamydiaceae, cyanobacteria, and the chloroplast
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DOI：
10.1101/gr.341802
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发表时间：
2002-08-01
期刊：
影响因子：
7
通讯作者：
Jones, SJM
中科院分区：
文献类型：
--
作者：
Brinkman, FSL;Blanchard, JL;Jones, SJM
在衣原体基因组中编码的蛋白质中，与植物蛋白质最相似的比例异常高，这导致了衣原体祖先从植物或植物样获得基因的建议。宿主生物通过水平基因转移。然而，在分析细菌-真核生物蛋白质相似性的过程中，我们发现衣原体中绝大多数植物样序列与靶向叶绿体的植物蛋白质最相似，叶绿体是一种来自蓝细菌的细胞器。我们提出了进一步的证据表明，植物样基因在衣原体，和其他衣原体科，可能是一个不受重视的衣原体科和蓝藻叶绿体谱系之间的进化关系的反映。细菌和真核生物基因组的进一步分析表明，在鉴定细菌-真核生物同源物或水平基因转移时，评估真核生物蛋白质的细胞器祖先的重要性，并支持衣原体科（Chlamydiaceae）是动物细胞内专性细菌病原体，不太可能与宿主交换DNA的提议。
An unusually high proportion of proteins encoded in Chlamydia genomes are most similar to plant proteins, leading to proposals that a Chlamydia ancestor obtained genes from a plant or plant-like. host organism by horizontal gene transfer. However, during an analysis of bacterial-eukaryotic protein similarities, we found that the vast majority of plant-like sequences in Chlamydia are most similar to plant proteins that are targeted to the chloroplast, an organelle derived from a cyanobacterium. We present further evidence suggesting that plant-like genes in Chlamydia, and other Chlamydiaceae, are likely a reflection of an unappreciated evolutionary relationship between the Chlamydiaceae and the cyanobacteria-chloroplast lineage. Further analyses of bacterial and eukaryotic genomes indicates the importance of evaluating organellar ancestry of eukaryotic proteins when identifying bacteria-eukaryote homologs or horizontal gene transfer and supports the proposal that Chlamydiaceae, which are obligate intracellular bacterial pathogens of animals, are not likely exchanging DNA with their hosts.