The ancestor of the Paulinella chromatophore obtained a carboxysomal operon by horizontal gene transfer from a Nitrococcus-like gamma-proteobacterium.
The ancestor of the Paulinella chromatophore obtained a carboxysomal operon by horizontal gene transfer from a Nitrococcus-like gamma-proteobacterium.
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DOI：
10.1186/1471-2148-7-85
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发表时间：
2007-06-05
影响因子：
3.4
通讯作者：
Melkonian M
中科院分区：
文献类型：
--
作者：
Marin B;Nowack EC;Glöckner G;Melkonian M
Paulinella chromatophora是一种淡水丝状变形虫，具有蓝细菌来源的光合内共生体（色素体），与自由生活的原绿球藻和聚球藻物种（PS分支）密切相关。蓝细菌的PS进化枝的成员含有通过羧基体操纵子的水平基因转移（HGT）获得的蛋白细菌形式1A RubisCO（核酮糖-1，5-二磷酸羧化酶/加氧酶）。在rDNA-peptigenies，Paulinella色素细胞分歧的PS-分支的基础上，提出了一个问题，无论是HGT发生之前或之后分裂的色素细胞的祖先。几乎完整的rDNA操纵子的系统发育分析与改进的分类单元采样包含最已知的蓝藻谱系恢复Paulinella chromophore作为妹妹完整的PS-分支。测定了Paulinella的完整羧基体操纵子的序列。RubisCO大亚基（rbcL）序列的分析表明，Paulinella共享的变形菌形式1A RubisCO与PS进化枝。γ-变形杆菌Nitrococcus mobilis被鉴定为Paulinella色素细胞和RubisCO系统发育中PS进化枝的姐妹。carboxysomal操纵子中的基因含量和顺序与RubisCO基因型相关，表明完整的carboxysomal操纵子是由Paulinella色素细胞和PS进化枝的共同祖先通过HGT获得的。carboxysomal操纵子显示出显着升高的AT含量Paulinella，这在rbcL基因仅限于第三密码子的位置。使用rbcL和rDNA操纵子的组合同源性导致PS进化枝的几乎完全解析的树。的carboxysomal操纵子的HGT早于分歧的色素细胞的祖先从PS-进化枝。以下HGT和分歧的色素细胞的祖先，多样化的PS分支到至少三个亚支发生。γ-变形杆菌运动硝化球菌代表了已知与羧基体操纵子的供体最近的相对物。Paulinella色素细胞在分子系统发育中的分离位置以及其升高的AT含量表明Paulinella色素细胞已经经历了内共生体还原进化的典型步骤。
Paulinella chromatophora is a freshwater filose amoeba with photosynthetic endosymbionts (chromatophores) of cyanobacterial origin that are closely related to free-living Prochlorococcus and Synechococcus species (PS-clade). Members of the PS-clade of cyanobacteria contain a proteobacterial form 1A RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) that was acquired by horizontal gene transfer (HGT) of a carboxysomal operon. In rDNA-phylogenies, the Paulinella chromatophore diverged basal to the PS-clade, raising the question whether the HGT occurred before or after the split of the chromatophore ancestor. Phylogenetic analyses of the almost complete rDNA operon with an improved taxon sampling containing most known cyanobacterial lineages recovered the Paulinella chromatophore as sister to the complete PS-clade. The sequence of the complete carboxysomal operon of Paulinella was determined. Analysis of RubisCO large subunit (rbcL) sequences revealed that Paulinella shares the proteobacterial form 1A RubisCO with the PS-clade. The γ-proteobacterium Nitrococcus mobilis was identified as sister of the Paulinella chromatophore and the PS-clade in the RubisCO phylogeny. Gene content and order in the carboxysomal operon correlates well with the RubisCO phylogeny demonstrating that the complete carboxysomal operon was acquired by the common ancestor of the Paulinella chromatophore and the PS-clade through HGT. The carboxysomal operon shows a significantly elevated AT content in Paulinella, which in the rbcL gene is confined to third codon positions. Combined phylogenies using rbcL and the rDNA-operon resulted in a nearly fully resolved tree of the PS-clade. The HGT of the carboxysomal operon predated the divergence of the chromatophore ancestor from the PS-clade. Following HGT and divergence of the chromatophore ancestor, diversification of the PS-clade into at least three subclades occurred. The γ-proteobacterium Nitrococcus mobilis represents the closest known relative to the donor of the carboxysomal operon. The isolated position of the Paulinella chromatophore in molecular phylogenies as well as its elevated AT content suggests that the Paulinella chromatophore has already undergone typical steps in the reductive evolution of an endosymbiont.
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影响因子：
4.4
作者：
Fuller, NJ;Marie, D;Scanlan, DJ
通讯作者：
Scanlan, DJ
影响因子：
6.9
作者：
Badger, MR;Price, GD;Woodger, FJ
通讯作者：
Woodger, FJ
影响因子：
2.8
作者：
Ernst, A;Becker, S;Postius, C
通讯作者：
Postius, C
DOI：
10.1073/pnas.93.7.2873
发表时间：
1996-04-02
影响因子：
11.1
作者：
Moran, NA
通讯作者：
Moran, NA
影响因子：
4.4
作者：
Rocap, G;Distel, DL;Chisholm, SW
通讯作者：
Chisholm, SW