The Multiply-Aligned Profiles for Global Alignment of Protein Sequences (MAPGAPS) procedure (135) was used alongside a variety of curated ePKs profiles (129, 136138) to identify and align ePK-related sequences from the nonredundant sequence database and UniProt reference proteome (139) databases (Release 2018_09). Sequences with a Cys residue at the Aurora A Cys290-equivalent position were retrieved and used for further taxonomic analysis. Taxonomic information was based on National Center for Biotechnology Information Taxonomy database (140) and WebLogos (141) were generated using WebLogo version 2.8. Amino acids were colored on the basis of their chemical properties. Polar (G, S, T, Y, C, Q, and N), basic (K, R, and H), acidic (D and E), and hydrophobic (A, V, L, I, P, W, and M) amino acids are colored green, blue, red, and black, respectively.