Fig. 3

Molecular models of the reconstructed ancestors and extant LiP. The hypothetical location of heme, two Ca²⁺ ions, ancestral Mn²⁺-binding site formed by two glutamate and one aspartate residues (red asterisks), evolved lignin-oxidizing exposed tryptophan (blue asterisks), and other relevant residues (Fig. 2) are shown on the ancestor models, built using three related crystal structures (4BM1, 3FJW, and 1QPA) as templates [57], and LiPH8 crystal structure (PDB 1B82). The models are shown on a schematic representation of evolution (see Fig. 1). The blue and gray arrows show the amino acids that appeared in the main evolutionary events and defined new activities (gain of catalytic Trp172 and loss of Mn²⁺-binding site, respectively)