Sequence alignment of cytidine deaminase orthologs from several organisms, including Trypanosoma brucei (XP_803607.1), Homo sapiens (NP_001776.1), Bacillus subtilis (KOS70912.1), Escherichia coli (KHJ23847.1), and Arabidopsis thaliana (CAA06460.1). Amino acids involved in the zinc binding site are highlighted with solid triangles, residues responsible for substrate binding are denoted by solid squares, amino acids involved in domain-domain interactions are indicated by asterisks, and conserved tyrosine residues in tetrameric CDAs are marked with solid circles. The alignment was visualized with JalView according to the Clustal color scheme (http://www.jalview.org/help/html/colourSchemes/clustal.html).