1tsq
From Proteopedia
|
CRYSTAL STRUCTURE OF AP2V SUBSTRATE VARIANT OF NC-P1 DECAMER PEPTIDE IN COMPLEX WITH V82A/D25N HIV-1 PROTEASE MUTANT
Overview
Maturation of human immunodeficiency virus (HIV) depends on the processing, of Gag and Pol polyproteins by the viral protease, making this enzyme a, prime target for anti-HIV therapy. Among the protease substrates, the, nucleocapsid-p1 (NC-p1) sequence is the least homologous, and its cleavage, is the rate-determining step in viral maturation. In the other substrates, of HIV-1 protease, P1 is usually either a hydrophobic or an aromatic, residue, and P2 is usually a branched residue. NC-p1, however, contains, Asn at P1 and Ala at P2. In response to the V82A drug-resistant protease, mutation, the P2 alanine of NC-p1 mutates to valine (AP2V). To provide a, structural rationale for HIV-1 protease binding to the NC-p1 cleavage, site, we solved the crystal structures of inactive (D25N) WT and V82A, HIV-1 proteases in complex with their respective WT and AP2V mutant NC-p1, substrates. Overall, the WT NC-p1 peptide binds HIV-1 protease less, optimally than the AP2V mutant, as indicated by the presence of fewer, hydrogen bonds and fewer van der Waals contacts. AlaP2 does not fill the, P2 pocket completely; PheP1' makes van der Waals interactions with Val82, that are lost with the V82A protease mutation. This loss is compensated by, the AP2V mutation, which reorients the peptide to a conformation more, similar to that observed in other substrate-protease complexes. Thus, the, mutant substrate not only binds the mutant protease more optimally but, also reveals the interdependency between the P1' and P2 substrate sites., This structural interdependency results from coevolution of the substrate, with the viral protease.
About this Structure
1TSQ is a Protein complex structure of sequences from [1] with ACT as ligand. Active as HIV-1 retropepsin, with EC number 3.4.23.16 Full crystallographic information is available from OCA.
Reference
Structural basis for coevolution of a human immunodeficiency virus type 1 nucleocapsid-p1 cleavage site with a V82A drug-resistant mutation in viral protease., Prabu-Jeyabalan M, Nalivaika EA, King NM, Schiffer CA, J Virol. 2004 Nov;78(22):12446-54. PMID:15507631
Page seeded by OCA on Thu Nov 8 14:31:41 2007
