Protein Domain : K02A2.6-like peptidase catalytic domain IPR034128

Type	Domain
Description	This entry includes a retropepsin-like domain of invertebrate retrotransposons with long terminal repeats [ ]. Although none of the proteins have been characterised, the retropepsin-like domain is presumed to be an aspartate endopeptidase. While fungal and mammalian pepsins are bilobal proteins with structurally related N- and C-termini, retropepsins are half as long as their fungal and mammalian counterparts []. The monomers are structurally related to one lobe of the pepsin molecule and retropepsins function as homodimers. The active site aspartate occurs within a motif (Asp-Thr/Ser-Gly), as it does in pepsin. In aspartate endopeptidases, Asp residues are ligands of an activated water molecule in all examples where catalytic residues have been identified. The retrotransposon aspartyl endopeptidase is synthesized as part of a polyprotein that also contains a reverse transcriptase and an integrase. The polyprotein is presumed to undergo specific enzymatic cleavage to yield the mature proteins. This group of aspartate endopeptidases is classified by MEROPS as peptidase family A28 [, ].
Short Name	K02A2.6-like