Phylogeny of galactolipid synthase homologs together with their enzymatic analyses revealed a possible origin and divergence time for photosynthetic membrane biogenesis.
Phylogeny of galactolipid synthase homologs together with their enzymatic analyses revealed a possible origin and divergence time for photosynthetic membrane biogenesis.
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DOI：
10.1093/dnares/dsr044
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Ohta H
中科院分区：
文献类型：
--
作者：
Yuzawa Y;Nishihara H;Haraguchi T;Masuda S;Shimojima M;Shimoyama A;Yuasa H;Okada N;Ohta H
蓝藻的光合膜和高等植物的叶绿体具有非常相似的脂质组成。特别是，蓝藻和叶绿体的类囊体膜由半乳糖脂组成，其中单半乳糖基二酰基甘油（MGDG）是最丰富的，尽管MGDG生物合成途径在这些生物体中是不同的。全面的系统发育分析表明，丝状缺氧光养生物绿球藻的MGDG合成酶（MGD）同源物与绿色植物纲（绿色藻类和陆地植物）的MGDG有密切的关系。此外，糖特异性和糖头基团的端基异构体构型的分析显示，其中一个MGD同系物表现出真正的MGDG合成活性。因此，我们推测，高等植物MGD衍生自这种祖先类型的MGD基因，和基因参与膜生物发生和光系统已经在功能上相关联，至少在绿丛枝分歧的时间。由于MGD基因复制是质体进化过程中的重要事件，我们还估算了A型和B型MGD的分化时间。我们的分析表明，这些基因在3.23亿年前出现分歧，当时种子植物（种子植物）出现。半乳糖脂的合成需要产生光合膜，基于MGD基因序列和活动，我们提出了一种新的进化模型，增加了我们对光合作用进化的理解。
The photosynthetic membranes of cyanobacteria and chloroplasts of higher plants have remarkably similar lipid compositions. In particular, thylakoid membranes of both cyanobacteria and chloroplasts are composed of galactolipids, of which monogalactosyldiacylglycerol (MGDG) is the most abundant, although MGDG biosynthetic pathways are different in these organisms. Comprehensive phylogenetic analysis revealed that MGDG synthase (MGD) homologs of filamentous anoxygenic phototrophs Chloroflexi have a close relationship with MGDs of Viridiplantae (green algae and land plants). Furthermore, analyses for the sugar specificity and anomeric configuration of the sugar head groups revealed that one of the MGD homologs exhibited a true MGDG synthetic activity. We therefore presumed that higher plant MGDs are derived from this ancestral type of MGD genes, and genes involved in membrane biogenesis and photosystems have been already functionally associated at least at the time of Chloroflexi divergence. As MGD gene duplication is an important event during plastid evolution, we also estimated the divergence time of type A and B MGDs. Our analysis indicated that these genes diverged ∼323 million years ago, when Spermatophyta (seed plants) were appearing. Galactolipid synthesis is required to produce photosynthetic membranes; based on MGD gene sequences and activities, we have proposed a novel evolutionary model that has increased our understanding of photosynthesis evolution.
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影响因子：
7.4
作者：
Blankenship, Robert E.
通讯作者：
Blankenship, Robert E.
影响因子：
4.8
作者：
Botte, Cyrille Y.;Yamaryo-Botte, Yoshiki;McFadden, Geoffrey I.
通讯作者：
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影响因子：
64.8
作者：
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通讯作者：
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影响因子：
7.4
作者：
Awai, Koichiro;Kakimoto, Takatoshi;Ohta, Hiroyuki
通讯作者：
Ohta, Hiroyuki
DOI：
10.1073/pnas.0704680104
发表时间：
2007-10-23
影响因子：
11.1
作者：
Kobayashi, Koichi;Kondo, Maki;Ohta, Hiroyuki
通讯作者：
Ohta, Hiroyuki