1A8K

CRYSTALLOGRAPHIC ANALYSIS OF HUMAN IMMUNODEFICIENCY VIRUS 1 PROTEASE WITH AN ANALOG OF THE CONSERVED CA-P2 SUBSTRATE: INTERACTIONS WITH FREQUENTLY OCCURRING GLUTAMIC ACID RESIDUE AT P2' POSITION OF SUBSTRATES

Summary for 1A8K

• Entry DOI: 10.2210/pdb1a8k/pdb
• Related PRD ID: PRD_000349
• Descriptor: HIV PROTEASE, N-[(2R)-2-({N~5~-[amino(iminio)methyl]-L-ornithyl-L-valyl}amino)-4-methylpentyl]-L-phenylalanyl-L-alpha-glutamyl-L-alanyl-L-norleucinamide (3 entities in total)
• Functional Keywords: human immunodeficiency virus protease, proton-mediated interaction, viral maturation, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• Biological source: Human immunodeficiency virus 1
• Cellular location: Matrix protein p17: Virion (Potential). Capsid protein p24: Virion (Potential). Nucleocapsid protein p7: Virion (Potential). Reverse transcriptase/ribonuclease H: Virion (Potential). Integrase: Virion (Potential): P03367
• Total number of polymer chains: 4
• Total formula weight: 44885.34

Authors

Weber, I.T.,Wu, J.,Adomat, J.,Harrison, R.W.,Kimmel, A.R.,Wondrak, E.M.,Louis, J.M. (deposition date: 1998-03-27, release date: 1999-01-13, Last modification date: 2024-05-22)

Primary citation

Weber, I.T.,Wu, J.,Adomat, J.,Harrison, R.W.,Kimmel, A.R.,Wondrak, E.M.,Louis, J.M.
Crystallographic analysis of human immunodeficiency virus 1 protease with an analog of the conserved CA-p2 substrate -- interactions with frequently occurring glutamic acid residue at P2' position of substrates.
Eur.J.Biochem., 249:523-530, 1997

PubMed Abstract: Human immunodeficiency virus type 1 (HIV-1) protease hydrolysis of the Gag CA-p2 cleavage site is crucial for virion maturation and is optimal at acidic pH. To understand the processing of the CA-p2 site, we have determined the structure of HIV-1 protease complexed with an analog of the CA-p2 site, the reduced peptide inhibitor Arg-Val-Leu-r-Phe-Glu-Ala-Ahx-NH2 [r denotes the reduced peptide bond and Ahx 2-aminohexanoic acid (norleucine), respectively]. The crystal structure was refined to an R-factor of 0.17 at 0.21-nm resolution. The crystals have nearly the same lattice as related complexes in P2(1)2(1)2(1) which have twofold disordered inhibitor, but are in space group P2(1). and the asymmetric unit contains two dimers of HIV-1 protease related by 180 degrees rotation. An approximate non-crystallographic symmetry has replaced the exact crystal symmetry resulting in well-ordered inhibitor structure. Each protease dimer binds one ordered inhibitor molecule, but in opposite orientations. The interactions of the inhibitor with the two dimers are very similar for the central P2 Val to P2' Glu residues, but show more variation for the distal P3 Arg and P4' Ahx residues. Importantly, the carboxylate oxygens of Glu at P2' in the inhibitor are within hydrogen-bonding distance of a carboxylate oxygen of Asp30 of the protease suggesting that the two side chains share a proton. This interaction suggests that the enzyme-substrate complex is additionally stabilized at lower pH. The importance of this interaction is emphasized by the absence of polymorphisms of Asp30 in the protease and variants of P2' Glu in the critical CA-p2 cleavage site.

PubMed: 9370363
DOI: 10.1111/j.1432-1033.1997.00523.x

Experimental method

X-RAY DIFFRACTION (2 Å)