目的 模块性和鲁棒性是微生物代谢网络的2个重要性质,但对于模块性和网络的结点度分布间的关系、网络鲁棒性和物种环境间的关系等问题仍不清楚.方法 基于KEGG的代谢数据库,构建了已有全基因组序列的1015种微生物代谢网络,利用现有方法计算了代谢网络的模块性和鲁棒性,分析了网络模块性和结点度分布、鲁棒性和物种环境间的关系.结果 微生物代谢网络的模块度显著高于度序列相同的模拟随机网络,而其紧密度低于这些随机网络.生活环境变化性大的物种的环境鲁棒性也较高,环境鲁棒性好的物种在自身环境下的网络鲁棒性相对较差.结论 代谢网络的高模块性不能完全由度序列分布情况来解释,物种代谢网络的鲁棒性和其生活环境密切相关.%Objective Modularity and robustness are two important properties of microbial metabolic networks. Yet there are still some questions unanswered, such as the relationship between network modularity and the node degree distribution, the relationship between network robustness and the environments of the species. Methods In this paper,we reconstructe metabolic networks for 1015 sequenced microbial species based on KEGG database, compute the values of modularity and robustness. Results Modularity values of these networks are significantly higher than simulated networks which have the same degree sequences, and their closeness values are lower. Species living in more variable environments have higher environment robustness in simulated conditions. And genetic robustness values in their own environments are relatively low for species with high environment robustness. Conclusions High modularity of metabolic networks cannot be fully explained by network node degree distribution, and the network robustness is closely related with the organism ' s living environment
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