3TIT | pdb_00003tit

Crystal structure of SARS coronavirus main protease complexed with an alpha, beta-unsaturated ethyl ester SG81

• PDB DOI: https://doi.org/10.2210/pdb3TIT/pdb

• Classification: Hydrolase/Hydrolase Inhibitor
• Organism(s): Severe acute respiratory syndrome-related coronavirus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2011-08-21 Released: 2012-08-22 
• Deposition Author(s): Zhu, L., Hilgenfeld, R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.99 Å
• R-Value Free: 
  0.235 (Depositor), 0.243 (DCC) 
• R-Value Work: 
  0.192 (Depositor), 0.200 (DCC) 
• R-Value Observed: 
  0.194 (Depositor) 

Literature

Crystal structures of SARS-Cov main protease complexed with a series of unsaturated esters

Zhu, L., Hilgenfeld, R.

To be published.

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: 34.35 kDa 
• Atom Count: 2,677 
• Modeled Residue Count: 306 
• Deposited Residue Count: 306 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
SARS coronavirus main protease	A	306	Severe acute respiratory syndrome-related coronavirus	Mutation(s): 0  EC: 3.4.19.12 (PDB Primary Data), 3.4.22.69 (PDB Primary Data), 3.4.22 (PDB Primary Data)
UniProt
Find proteins for P0C6X7 (Severe acute respiratory syndrome coronavirus) Explore P0C6X7  Go to UniProtKB:  P0C6X7

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
G81	B [auth A]	ETHYL (4R)-4-{[N-(TERT-BUTOXYCARBONYL)-L-PHENYLALANYL]AMINO}-5-[(3S)-2-OXOPYRROLIDIN-3-YL]PENTANOATE C25 H37 N3 O6 CUCJJUOQGSQGLL-ZCNNSNEGSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.99 Å
• R-Value Free:  0.235 (Depositor), 0.243 (DCC) 
• R-Value Work:  0.192 (Depositor), 0.200 (DCC) 
• R-Value Observed: 0.194 (Depositor) 

Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 108.01	α = 90
b = 83.14	β = 104.63
c = 53.48	γ = 90

Software Package:

Software Name	Purpose
MAR345	data collection
MOLREP	phasing
REFMAC	refinement
iMOSFLM	data reduction
SCALA	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-08-22 
Deposition Author(s): Zhu, L., Hilgenfeld, R.

Revision History  

• Version 1.0: 2012-08-22
  Type: Initial release
  
• Version 1.1: 2017-11-08
  Changes: Refinement description
• Version 1.2: 2024-10-16
  Changes: Data collection, Database references, Derived calculations, Structure summary