Analysis of WGD-enzymes in metabolic network. (A) Comparison of three topological centralities between WGD-enzymes and the other enzymes. (B) Sub-network of WGD-enzymes. Dots represent enzymes and the lines represent the interactions among enzymes. (C) The distribution of IBWEs in 1000 randomization simulations. The arrow on the right hand side represents the observed number of IBWE.