9BO0 | pdb_00009bo0

Crystal Structure of T21I SARS-CoV-2 Main Protease in Complex with Compound Mpro61


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.16 Å
  • R-Value Free: 
    0.251 (Depositor), 0.250 (DCC) 
  • R-Value Work: 
    0.219 (Depositor), 0.220 (DCC) 
  • R-Value Observed: 
    0.220 (Depositor) 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.1 of the entry. See complete history


Literature

Exploring Possible Drug-Resistant Variants of SARS-CoV-2 Main Protease (M pro ) with Noncovalent Preclinical Candidate, Mpro61.

Kenneson, J.R.Papini, C.Tang, S.Huynh, K.Zhang, C.H.Jorgensen, W.L.Anderson, K.S.

(2025) ACS Bio Med Chem Au 5: 215-226

  • DOI: https://doi.org/10.1021/acsbiomedchemau.4c00109
  • Primary Citation of Related Structures:  
    9BNT, 9BNU, 9BNV, 9BNW, 9BNX, 9BNY, 9BNZ, 9BO0, 9BO1, 9BO2, 9BO3, 9BO4, 9BO5, 9BO6, 9BO7, 9BO8, 9BO9, 9BOA, 9BOB, 9BOC, 9BOD, 9BOE, 9CDK, 9CDL, 9CDM

  • PubMed Abstract: 

    SARS-CoV-2 M pro inhibitors, such as nirmatrelvir, have proven efficacy in clinical use. Nirmatrelvir was developed in a target-based approach against wild-type M pro , with the anticipation that prolonged usage may cause enrichment of drug-resistant mutations and persistence of COVID infections. Although globally prevalent drug-resistant mutations have not yet been observed, individual cases have recently been reported among patients following treatment with Paxlovid-a formulation of nirmatrelvir. Mutations E166V and E166A have been detected in these drug-resistant clinical isolates, consistent with predictions from in vitro viral passage experiments and therefore necessitate ongoing drug development. In this study, we selected seven M pro variants (T21I, L50F, E166V, A173V, T190I, E166V/L50F, and A173V/L50F), which have been repeatedly found in viral passage experiments. We investigated their kinetic and structural properties, as well as resistance level to M pro inhibitors: nirmatrelvir, GC376-a similar peptidomimetic for feline COVID infections, and our in-house-developed nonpeptidomimetic inhibitor Mpro61. Mpro61 maintains potency against the single variants (except for E166V) and the A173/L50F double variant, with K i values similar to those of the wild type. In contrast, while nirmatrelvir and GC376 were still effective against the A173V/L50F double variant, their K i values significantly increased up to 10-fold. None of the inhibitors appeared to be potent against E166V-containing variants. Our structural analysis revealed a significant movement of Ser1 residue in all E166V-containing variants in the presence or absence of an inhibitor. The new orientation of the Ser1 suggested potential strategies for medicinal chemistry modifications of Mpro61 to enhance hydrogen-bonding interactions between these variants and Mpro61 derivatives. These studies provide critical insights into guiding the future design of additional Mpro61 derivatives that would potentially inhibit variants with the pan-drug-resistant E166V mutation.


  • Organizational Affiliation

    Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520-8066, United States.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
3C-like proteinase
A, B
306Severe acute respiratory syndrome coronavirus 2Mutation(s): 1 
EC: 3.4.22.69
UniProt
Find proteins for P0DTC1 (Severe acute respiratory syndrome coronavirus 2)
Explore P0DTC1 
Go to UniProtKB:  P0DTC1
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0DTC1
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
XEK (Subject of Investigation/LOI)
Query on XEK

Download Ideal Coordinates CCD File 
C [auth A](5P)-5-[(1P,3M,3'P)-3-{3-chloro-5-[(2-chlorophenyl)methoxy]-4-fluorophenyl}-2-oxo-2H-[1,3'-bipyridin]-5-yl]-1-methylpyrimidine-2,4(1H,3H)-dione
C28 H19 Cl2 F N4 O4
KIJKUSPNZALBLD-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.16 Å
  • R-Value Free:  0.251 (Depositor), 0.250 (DCC) 
  • R-Value Work:  0.219 (Depositor), 0.220 (DCC) 
  • R-Value Observed: 0.220 (Depositor) 
Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 67.76α = 90
b = 100.124β = 90
c = 103.908γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
XDSdata reduction
Aimlessdata scaling
PHENIXphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesP30 GM133893
Department of Energy (DOE, United States)United StatesKP1607011
Other governmentDE-SC0012704

Revision History  (Full details and data files)

  • Version 1.0: 2025-02-12
    Type: Initial release
  • Version 1.1: 2025-03-12
    Changes: Database references