Structure-based alignment of ODCs from T. brucei (2toda) (ExPASy accession number: P07805), H. sapiens (1d7ka) (ExPASy accession number: P11926), M. musculus (7odca) (ExPASy accession number: P00860), and E. histolytica (36.t00008) (GenBank accession number: Q58P26).

(A) The structural environments of the residues in the known structures are encoded in the representation: Upper case letters are solvent-inaccessible amino acids; lower case letters are solvent accessible; italicized letters are residues with a positive φ (one of the Ramachandran angles); bold letters indicate a side chain hydrogen bonded to the main chain amide; underlined letters indicate a side chain hydrogen bonded to the main chain carbonyl. The numbers within parenthesis represent the first residue of the given protein in a block. Conserved α-helical, 3₁₀ helical, and β-strand regions are indicated at the end of every alignment block as a, 3, and b respectively. Figure produced using JOY [34]. (B) Multiple sequence alignment of putative ODC-like sequence from E. histolytica (GenBank accession number AAX35675), T. brucei ODC (GenBank accession number AAA30219), human ODC (GenBank accession number AAA59967), and Datura stramonium ODC (GenBank accession number CAA61121) using ClustalW. The amino acids are numbered to the left of the respective sequences. Residues that are identical or similar to other ODCs are indicated in black showing complete identity, and grey when they are conserved in at least three sequences. Short dashed line below the sequence represents the pyridoxal phosphate binding site. Line of asterisks (*) represents the DFMO binding site.