中文摘要：

近几年，复杂网络的研究正成为广泛关注的热点，代谢网络是复杂网络的一个例子。本文以产甲烷的常温古细菌Methanosarcina acetivoransm（M.acetivorans）和嗜热古细菌Methanopyrusk and lerimlmndleri）的代谢网络为对象，从拓扑参数以及模块化两方面进行比较研究。结果表明：M.acetivorans与M.kandleri的代谢网络均具有较高的模块化结构。同时发现它们模块化后的代谢网络中的Hub模块均属于氨基酸代谢和碳水化合物代谢，表明这些网络模块均具有一定的功能意义。最后将Hub模块与最紧密的卜核心网络相比较，发现它们节点完全相同，此结果表明代谢网络的最紧密卜核心网络部分也是不同网络比较的重要因素。

英文摘要：

Recently, the study of complex networks is becoming a popular research field. Metabolic network is a typical example of complex networks. By comparing the topological parameters and modularization of metabolic network of mesophilic Methanosarcina acetivorans（M. acetivorans） and thermophilic Methanopyrus kandleri（ M. kandleri）, the results show that the metabolic networks of M. acetivorans and M. kandleri have a high modular structure. Meanwhile, hub modules of metabolic network after modularization are the amino acid metabolism and carbohydrate metabolism. It indicates that these network modules have functional significance. Finally, we find the Hub modules have the same nodes as the closest k-core sub networks by comparison. The results show that closest k-core sub networks are an important factor when comparing different metabolic networks.