Type: | Domain | Name: | Peptidase A2A, retrovirus, catalytic |
Description: | Aspartic endopeptidases of vertebrate, fungal and retroviral origin have been characterised []. More recently, aspartic endopeptidases associated with the processing of bacterial type 4 prepilin [] and archaean preflagellin have been described [, ].Structurally, aspartic endopeptidases are bilobal enzymes, each lobe contributing a catalytic Asp residue, with an extended active site cleft localised between the two lobes of the molecule. One lobe has probably evolved from the other through a gene duplication event in the distant past. In modern-day enzymes, although the three-dimensional structures are very similar, the amino acid sequences are more divergent, except for the catalytic site motif, which is very conserved. The presence and position of disulphide bridges are other conserved features of aspartic peptidases. All or most aspartate peptidases are endopeptidases. These enzymes have been assigned into clans (proteins which are evolutionary related), and further sub-divided into families, largely on the basis of their tertiary structure.This group of aspartic peptidases belong to the MEROPS peptidase family A2 (retropepsin family, clan AA), subfamily A2A. The family includes the single domain aspartic proteases from retroviruses, retrotransposons, and badnaviruses (plant dsDNA viruses).Retroviral aspartyl protease is synthesised as part of the POL polyprotein that contains; an aspartyl protease, a reverse transcriptase, RNase H and integrase. POL polyprotein undergoes specific enzymatic cleavage to yield the mature proteins. | Short Name: | Peptidase_A2_cat |