Functional convergence in reduced genomes of bacterial symbionts spanning 200 My of evolution.
Functional convergence in reduced genomes of bacterial symbionts spanning 200 My of evolution.
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DOI：
10.1093/gbe/evq055
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发表时间：
2010
影响因子：
3.3
通讯作者：
Moran NA
中科院分区：
文献类型：
--
作者：
McCutcheon JP;Moran NA
宿主限制性微生物共生体进化过程中的主要基因组变化是基因的持续失活和丢失，并结合快速的序列进化和极端的结构稳定性；这些变化反映了由于种群规模小和严格的克隆性而导致的高水平遗传漂变。这种基因组侵蚀包括许多功能类别基因的不可逆转的损失，可能包括对宿主的营养贡献的基因，这是共生关系的基础。候选菌（Candidatus Sulcia muelleri）是一种以汁液为食的昆虫的古老共生体，通常与另一种在宿主亚分支中变化的细菌共生体共生。先前测序的Sulcia基因组保留了相同的8种必需氨基酸的途径，而共生生物合成了剩余的两种氨基酸。本文描述了一个由Sulcia和Betaproteobacteria Candidatus Zinderia杀虫剂组成的双重共生系统，两者都生活在亚利桑那州裂翅目（Clastoptera arizonana）中。这种藻已经完全失去了生物合成色氨酸的途径，因此，只保留了制造10种必需氨基酸中的7种的能力。Zinderia有一个很小的基因组（208 kb）和迄今为止报道的最极端的核苷酸碱基组成（13.5% G + C），但保留了制造其余三种必需氨基酸的能力，完美地补充了总统Sulcia的能力。结合来自完整基因组的相关共生系统的结果，这些数据证明了细菌共生体在宿主昆虫生物学中发挥的关键作用，并揭示了通过基因组减少失去关键代谢活性后的一个结果。
The main genomic changes in the evolution of host-restricted microbial symbionts are ongoing inactivation and loss of genes combined with rapid sequence evolution and extreme structural stability; these changes reflect high levels of genetic drift due to small population sizes and strict clonality. This genomic erosion includes irreversible loss of genes in many functional categories and can include genes that underlie the nutritional contributions to hosts that are the basis of the symbiotic association. Candidatus Sulcia muelleri is an ancient symbiont of sap-feeding insects and is typically coresident with another bacterial symbiont that varies among host subclades. Previously sequenced Sulcia genomes retain pathways for the same eight essential amino acids, whereas coresident symbionts synthesize the remaining two. Here, we describe a dual symbiotic system consisting of Sulcia and a novel species of Betaproteobacteria, Candidatus Zinderia insecticola, both living in the spittlebug Clastoptera arizonana. This Sulcia has completely lost the pathway for the biosynthesis of tryptophan and, therefore, retains the ability to make only 7 of the 10 essential amino acids. Zinderia has a tiny genome (208 kb) and the most extreme nucleotide base composition (13.5% G + C) reported to date, yet retains the ability to make the remaining three essential amino acids, perfectly complementing capabilities of the coresident Sulcia. Combined with the results from related symbiotic systems with complete genomes, these data demonstrate the critical role that bacterial symbionts play in the host insect’s biology and reveal one outcome following the loss of a critical metabolic activity through genome reduction.
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影响因子：
4.5
作者：
Audic S;Robert C;Campagna B;Parinello H;Claverie JM;Raoult D;Drancourt M
通讯作者：
Drancourt M
DOI：
10.1073/pnas.0906424106
发表时间：
2009-09-08
影响因子：
11.1
作者：
McCutcheon, John P.;McDonald, Bradon R.;Moran, Nancy A.
通讯作者：
Moran, Nancy A.
影响因子：
4.4
作者：
Moran, NA;Tran, P;Gerardo, NM
通讯作者：
Gerardo, NM
影响因子：
14.9
作者：
Cole JR;Wang Q;Cardenas E;Fish J;Chai B;Farris RJ;Kulam-Syed-Mohideen AS;McGarrell DM;Marsh T;Garrity GM;Tiedje JM
通讯作者：
Tiedje JM
影响因子：
7
作者：
Degnan, PH;Lazarus, AB;Wernegreen, JJ
通讯作者：
Wernegreen, JJ