Fig. 1

Multiple sequence alignment and structural superposition of retroviral aspartyl peptidase domain of from T. cruzi and HIV-1. a Multiple sequence alignment of the retroviral aspartyl peptidase domains of T. cruzi and the HIV-1 peptidase (TcRP-A: UNIPROT ID Q4E0H2, TcRP-B: UNIPROT ID Q4E178, HIV-1 peptidase: PDB ID 3OXC). The active site residues from the T. cruzi domains are highlighted in light orange. Above the aligned sequences, identical sequences are indicated by an asterisk (*), residues with strongly similar properties are indicated by a colon (:), and residues with weakly similar properties are indicated by a period (.). Below the aligned sequences, blue arrows indicate β-sheet, while the red cylinder indicates α helices in the secondary structure of the protein. b Structural superposition of the 3D structures of HIV-1 peptidase (PDB ID 3OXC, in grey) and the TcRP-B model (in brown) in cartoon representation. The catalytic aspartates (Asp248A and B) are represented in sticks. c Surface and cartoon representation of the active site of TcRP-B model. The amino acids located in the active site are represented in sticks and the glycine residues are represented in spheres. TcRP-A model presented similar results (data not shown)