Unraveling the genomic mosaic of a ubiquitous genus of marine cyanobacteria.
Unraveling the genomic mosaic of a ubiquitous genus of marine cyanobacteria.
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DOI：
10.1186/gb-2008-9-5-r90
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发表时间：
2008
期刊：
影响因子：
12.3
通讯作者：
Partensky, Frederic
中科院分区：
文献类型：
--
作者：
Dufresne, Alexis;Ostrowski, Martin;Scanlan, David J.;Garczarek, Laurence;Mazard, Sophie;Palenik, Brian P.;Paulsen, Ian T.;de Marsac, Nicole Tandeau;Wincker, Patrick;Dossat, Carole;Ferriera, Steve;Johnson, Justin;Post, Anton F.;Hess, Wolfgang R.;Partensky, Frederic
海洋聚珠球菌谱系的局部生态位占用是由横向基因转移促进的。基因组岛是这些转移基因的储存库。聚球藻属的花青菌分布在广阔的海洋中，在光带中占据了大多数可用的生态位。不同聚球菌枝的大规模分布模式（基于16S rRNA基因标记）表明，存在两种主要的生活方式（“机会主义者”/“专家”），对应于两种不同的广阔栖息地（“沿海”/“公海”）。然而，在这个重要的生态群体中，生态位分配的遗传基础仍然知之甚少。在这里，我们比较了11个海洋聚囊球菌分离株的基因组，代表了10个不同的谱系。从核心基因组推断出的系统发育使我们能够通过揭示主亚群内的明确二分法来完善进化支之间的分类关系，让人想起前面提到的两种生活方式。基因组大小与高变区（或“岛”）的累积长度密切相关。其中之一，包含了大多数编码光收集藻胆体棒状复合物的基因，参与了对光质量变化的适应，并且显然已经在不同的聚球菌谱系成员之间转移。此外，我们观察到两个具有相似色素沉着和生理的菌株（RS9917和WH5701）具有异常高的共同基因数量，考虑到它们的系统发育距离。我们提出，虽然特定海洋聚球菌谱系的成员可能具有相同的广泛地理分布，但基因横向转移促进了局部生态位的占据，在这一过程中，基因组岛作为转移基因的储存库发挥了关键作用。我们的工作还强调了基于基因组衍生参数结合生态和生理数据开发picocyanobacterian系统学的必要性。
Local niche occupancy of marine Synechococcus lineages is facilitated by lateral gene transfers. Genomic islands act as repositories for these transferred genes. The picocyanobacterial genus Synechococcus occurs over wide oceanic expanses, having colonized most available niches in the photic zone. Large scale distribution patterns of the different Synechococcus clades (based on 16S rRNA gene markers) suggest the occurrence of two major lifestyles ('opportunists'/'specialists'), corresponding to two distinct broad habitats ('coastal'/'open ocean'). Yet, the genetic basis of niche partitioning is still poorly understood in this ecologically important group. Here, we compare the genomes of 11 marine Synechococcus isolates, representing 10 distinct lineages. Phylogenies inferred from the core genome allowed us to refine the taxonomic relationships between clades by revealing a clear dichotomy within the main subcluster, reminiscent of the two aforementioned lifestyles. Genome size is strongly correlated with the cumulative lengths of hypervariable regions (or 'islands'). One of these, encompassing most genes encoding the light-harvesting phycobilisome rod complexes, is involved in adaptation to changes in light quality and has clearly been transferred between members of different Synechococcus lineages. Furthermore, we observed that two strains (RS9917 and WH5701) that have similar pigmentation and physiology have an unusually high number of genes in common, given their phylogenetic distance. We propose that while members of a given marine Synechococcus lineage may have the same broad geographical distribution, local niche occupancy is facilitated by lateral gene transfers, a process in which genomic islands play a key role as a repository for transferred genes. Our work also highlights the need for developing picocyanobacterial systematics based on genome-derived parameters combined with ecological and physiological data.
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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：
5.1
作者：
Haverkamp, Thomas;Acinas, Silvia G.;Stal, Lucas J.
通讯作者：
Stal, Lucas J.
影响因子：
10.7
作者：
LENTO, GM;HICKSON, RE;PENNY, D
通讯作者：
PENNY, D
影响因子：
10.7
作者：
Castresana, J
通讯作者：
Castresana, J
DOI：
10.1073/pnas.0409727102
发表时间：
2005-02-15
影响因子：
11.1
作者：
Konstantinidis, KT;Tiedje, JM
通讯作者：
Tiedje, JM