Figure 1b.

(B) Phylogenetic analysis of the PPAE-inhibitory serpins. Proteins that have been shown biochemically to inhibit PPAEs are marked with an asterisk. The tree was estimated from 264 aligned residues. (C) Sequence similarities of reactive centre loops (P1–P1′ cleavage sites; arrow) of SRPN2-like serpins (SRPN2 cluster in (A)) with the activation cleavage sites of PPOs from the same species (arrowhead). Note the strong similarities in residues flanking the serpin and corresponding PPO sites, and the resemblance of the neighbouring amino-acid environments.