Table 1.

Properties of the three metabolic networks.

	Core (yellow) network	Intermediate (green) network	Complete (blue) network
Number of nodes	770	1207	2288
Number of edges	2255	3792	6547
Network density	0.008	0.005	0.002
Network heterogeneity	2.223	2.623	3.362
Number of self-loops	0	8	31
Clustering coefficient	0.215	0.233	0.189
Connected components	6	5	28
Network diameter	8	8	10
Network centralisation	0.288	0.301	0.271
Average path length	3.114	3.158	3.286
Average connectivity	5.857	6.270	5.696

The meaning of the parameters given in this table is explained in the Methods section.