中文摘要：

在在酶和他们的功能之中的拓扑的连接之间的关系在新陈代谢的网络进化期间是什么？这种关系在密切相关的有机体之中显示出类似吗？这里，我们在叶绿体和它的 endosymbiotic 祖先的新陈代谢的网络调查了在酶连接和函数之间的关系， cyanobacteria (Synechococcus sp。WH8102 ) 。另外几另外的种，包括 E。关口 i， Arabidopsis thaliana 和 Cyanidioschyzon merolae，被用于比较。我们发现在不同功能的小径和分类(EC ) 之中的平均连接在检验的所有种类是不同的。然而，在一样的功能的分类的酶的平均连接在叶绿体和 cyanobacteria 的一个代表之间是相当类似的， syw。另外，在在叶绿体和 syw 之间的高度保存的模块中的酶例如氨基酸新陈代谢，高度与另外的模块相比被连接。我们也发现叶绿体和 syw 的 isozymes 经常有更高的连接，对应于主要新陈代谢并且也在保存模块中存在。在结论，尽管有在叶绿体的新陈代谢的激烈的重组在 endosymbiosis 期间，在网络拓扑学和功能之间的关系在叶绿体和它的先锋 cyanobacteria 之间是很类似的，它证明关系可以在进化被用作亲密的指示物。

英文摘要：

What is the relationship between the topological connections among enzymes and their functions during metabolic network evolution？ Does this relationship show similarity among closely related organisms？ Here we investigated the relationship between enzyme connectivity and functions in metabolic networks of chloroplast and its endosymbiotic ancestor, cyanobacteria （Synechococcus sp. WH8102）. Also several other species, including E. coli, Arabidopsis thaliana and Cyanidioschyzon merolae, were used for the comparison. We found that the average connectivity among different functional pathways and enzyme classifications （EC） was different in all the species examined. However, the average connectivity of enzymes in the same functional classification was quite similar between chloroplast and one representative of cyanobacteria, syw. In addition, the enzymes in the highly conserved modules between chloroplast and syw, such as amino acid metabolism, were highly connected compared with other modules. We also discovered that the isozymes of chloroplast and syw often had higher connectivity, corresponded to primary metabolism and also existed in conserved module. In conclusion, despite the drastic re-organization of metabolism in chloroplast during endosymbiosis, the relationship between network topology and functions is very similar between chloroplast and its precursor cyanobacteria, which demonstrates that the relationship may be used as an indicator of the closeness in evolution.