1A9M

G48H MUTANT OF HIV-1 PROTEASE IN COMPLEX WITH A PEPTIDIC INHIBITOR U-89360E

• PDB DOI: https://doi.org/10.2210/pdb1A9M/pdb

• Classification: ASPARTYL PROTEASE
• Organism(s): Human immunodeficiency virus 1
• Expression System: Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 1998-04-08 Released: 1998-06-17 
• Deposition Author(s): Hong, L., Zhang, X.-J., Foundling, S., Hartsuck, J.A., Tang, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Work: 
  0.185 (Depositor) 
• R-Value Observed: 
  0.185 (Depositor) 

Starting Model: experimental

Literature

Structure of a G48H mutant of HIV-1 protease explains how glycine-48 replacements produce mutants resistant to inhibitor drugs.

Hong, L., Zhang, X.J., Foundling, S., Hartsuck, J.A., Tang, J.

(1997) FEBS Lett 420: 11-16

• PubMed: 9450540 
• DOI: https://doi.org/10.1016/s0014-5793(97)01477-4
• Primary Citation of Related Structures:  
  1A9M


• PubMed Abstract: 
  

  The crystal structure of human immunodeficiency virus type 1 (HIV-1) protease mutant G48H with peptidic inhibitor U-89360E is described. Comparison with wild-type protease-inhibitor complex shows that mutation of flap residue 48 to histidine allows stabilizing van der Waals contacts between the side chains of His48 and Phe53 as well as between His48 and the P2' and P3' inhibitor subsites. The flap region is less mobile than in the wild-type enzyme. A model of saquinavir-resistant mutant protease G48V in complex with saquinavir predicts interactions similar to those found in the G48H crystal. Energetic calculations confirm the similarity of the His48 and Val48 interactions.

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Organizational Affiliation: 

Protein Studies Program, Oklahoma Medical Research Foundation, Oklahoma City 73104, USA.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 22.37 kDa 
• Atom Count: 1,629 
• Modelled Residue Count: 198 
• Deposited Residue Count: 198 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
HIV-1 PROTEASE	A, B	99	Human immunodeficiency virus 1	Mutation(s): 1
UniProt
Find proteins for P03366 (Human immunodeficiency virus type 1 group M subtype B (isolate BH10)) Explore P03366  Go to UniProtKB:  P03366

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
U0E	C [auth B]	N-[[1-[N-ACETAMIDYL]-[1-CYCLOHEXYLMETHYL-2-HYDROXY-4-ISOPROPYL]-BUT-4-YL]-CARBONYL]-GLUTAMINYL-ARGINYL-AMIDE C28 H52 N8 O6 XTOQWMLQBSGKOK-VUBDRERZSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Work:  0.185 (Depositor) 
• R-Value Observed: 0.185 (Depositor) 

Space Group: I 2 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 58.5	α = 90
b = 88.2	β = 90
c = 94.2	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
SAINT	data reduction
SAINT	data scaling
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1998-06-17 
Deposition Author(s): Hong, L., Zhang, X.-J., Foundling, S., Hartsuck, J.A., Tang, J.

Revision History  

• Version 1.0: 1998-06-17
  Type: Initial release
  
• Version 1.1: 2008-03-03
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2021-11-03
  Changes: Database references, Derived calculations, Other
• Version 1.4: 2023-08-02
  Changes: Refinement description
• Version 1.5: 2024-05-22
  Changes: Data collection