11FB | pdb_000011fb

Structure of GDP-bound KRAS-G12C/Y96C, a Switch-II Pocket Inhibitor Resistance Mutant

• PDB DOI: https://doi.org/10.2210/pdb11FB/pdb

• Classification: SIGNALING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2026-02-20 Released: 2026-10-07 
• Deposition Author(s): Whitley, M.J., Simanshu, D.K.
• Funding Organization(s): National Institutes of Health/National Cancer Institute (NIH/NCI)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Free: 
  0.200 (Depositor), 0.200 (DCC) 
• R-Value Work: 
  0.177 (Depositor), 0.177 (DCC) 
• R-Value Observed: 
  0.178 (Depositor) 

Starting Model: experimental

Literature

Structural mechanisms underlying resistance to Switch-II pocket inhibitors in KRAS

Whitley, M.J., Dyba, M., Chakrabarti, M., Smith, B.P., Chan, A.H., Denson, J.P., Messing, S.A., Lin, K., Cornilescu, G., Balius, T.E., Nissley, D.V., McCormick, F., Maciag, A.E., Simanshu, D.K.

(2026) Nat Commun 

• DOI: https://doi.org/10.1038/s41467-026-78133-4

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Biological Assembly Evidence: gel filtration

Macromolecule Content 

• Total Structure Weight: 19.89 kDa 
• Atom Count: 1,573 
• Modeled Residue Count: 166 
• Deposited Residue Count: 170 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
GTPase KRas	A	170	Homo sapiens	Mutation(s): 3  Gene Names: KRAS, KRAS2, RASK2 EC: 3.6.5.2
UniProt & NIH Common Fund Data Resources
Find proteins for P01116 (Homo sapiens) Go to UniProtKB:  P01116
PHAROS:  P01116 GTEx:  ENSG00000133703

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GDP (Subject of Investigation/LOI)	C [auth A]	GUANOSINE-5'-DIPHOSPHATE C10 H15 N5 O11 P2 QGWNDRXFNXRZMB-UUOKFMHZSA-N
TRS	D [auth A]	2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL C4 H12 N O3 LENZDBCJOHFCAS-UHFFFAOYSA-O
MG	B [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Free:  0.200 (Depositor), 0.200 (DCC) 
• R-Value Work:  0.177 (Depositor), 0.177 (DCC) 
• R-Value Observed: 0.178 (Depositor) 

Space Group: H 3 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 92.837	α = 90
b = 92.837	β = 90
c = 119.185	γ = 120

Software Package:

Software Name	Purpose
XDS	data reduction
XDS	data scaling
MoRDa	phasing
PHENIX	refinement
PDB_EXTRACT	data extraction

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-10-07 
Deposition Author(s): Whitley, M.J., Simanshu, D.K.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Cancer Institute (NIH/NCI)	United States	75N91019D00024

Revision History  

• Version 1.0: 2026-10-07
  Type: Initial release