Figure 1

Structural comparison of HsUBC13 and the putative PfUBC13. (a) Homo sapiens (Hs)UBC13 and Plasmodium falciparum (Pf)UBC13 amino acid sequences are aligned, with identical residues in the two sequences highlighted in black. The active site cysteine residue that binds activated ubiquitin covalently and reacts with NSC697923 in human UBC13 is highlighted in yellow and marked with an asterisk. (b) Three- dimensional structures with the active site cysteine highlighted in yellow and marked with an asterisk. In the PfUBC13 structure, amino acid residues where the two sequences differ are highlighted in blue, or in cyan if the substitution is conservative.