Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

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: 52.34 kDa 
• Atom Count: 3082 
• Modelled Residue Count: 366 
• Deposited Residue Count: 446 
• Unique protein chains: 1

6HHF

Crystal Structure of AKT1 in Complex with Covalent-Allosteric AKT Inhibitor Borussertib

• PDB DOI: 10.2210/pdb6HHF/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda
• Mutation(s): Yes 


• Deposited: 2018-08-28 Released: 2019-03-20 
• Deposition Author(s): Landel, I., Weisner, J., Mueller, M.P., Scheinpflug, R., Rauh, D.
• Funding Organization(s): German Federal Ministry for Education and Research

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.274 
• R-Value Work: 0.231 
• R-Value Observed: 0.233 

Literature

Preclinical Efficacy of Covalent-Allosteric AKT Inhibitor Borussertib in Combination with Trametinib inKRAS-Mutant Pancreatic and Colorectal Cancer.

Weisner, J., Landel, I., Reintjes, C., Uhlenbrock, N., Trajkovic-Arsic, M., Dienstbier, N., Hardick, J., Ladigan, S., Lindemann, M., Smith, S., Quambusch, L., Scheinpflug, R., Depta, L., Gontla, R., Unger, A., Muller, H., Baumann, M., Schultz-Fademrecht, C., Gunther, G., Maghnouj, A., Muller, M.P., Pohl, M., Teschendorf, C., Wolters, H., Viebahn, R., Tannapfel, A., Uhl, W., Hengstler, J.G., Hahn, S.A., Siveke, J.T., Rauh, D.

(2019) Cancer Res 79: 2367-2378

• PubMed: 30858154 
• DOI: 10.1158/0008-5472.CAN-18-2861
• Primary Citation of Related Structures:  
  6HHF


• PubMed Abstract: 
  

Aberrations within the PI3K/AKT signaling axis are frequently observed in numerous cancer types, highlighting the relevance of these pathways in cancer physiology and pathology. However, therapeutic interventions employing AKT inhibitors often suffer from limitations associated with target selectivity, efficacy, or dose-limiting effects. Here we present the first crystal structure of autoinhibited AKT1 in complex with the covalent-allosteric inhibitor borussertib, providing critical insights into the structural basis of AKT1 inhibition by this unique class of compounds. Comprehensive biological and preclinical evaluation of borussertib in cancer-related model systems demonstrated a strong antiproliferative activity in cancer cell lines harboring genetic alterations within the PTEN, PI3K, and RAS signaling pathways. Furthermore, borussertib displayed antitumor activity in combination with the MEK inhibitor trametinib in patient-derived xenograft models of mutant KRAS pancreatic and colon cancer. SIGNIFICANCE: Borussertib, a first-in-class covalent-allosteric AKT inhibitor, displays antitumor activity in combination with the MEK inhibitor trametinib in patient-derived xenograft models and provides a starting point for further pharmacokinetic/dynamic optimization.

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Organizational Affiliation: 

Drug Discovery Hub Dortmund (DDHD) am Zentrum für Integrierte Wirkstoffforschung (ZIW), Dortmund, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
RAC-alpha serine/threonine-protein kinase	A	446	Homo sapiens	Mutation(s): 3  Gene Names: AKT1, PKB, RAC EC: 2.7.11.1
UniProt & NIH Common Fund Data Resources
Find proteins for P31749 (Homo sapiens) Explore P31749  Go to UniProtKB:  P31749
PHAROS:  P31749 GTEx:  ENSG00000142208

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
G4K	B [auth A]	Borussertib C36 H34 N6 O3 NFXSQFADJLOQHR-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
G4K	BindingDB:  6HHF	Kd: 62 (nM) from 1 assay(s)
		IC50: 7.5 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.274 
• R-Value Work: 0.231 
• R-Value Observed: 0.233 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 64.37	α = 90
b = 68.44	β = 90
c = 102.51	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
XDS	data reduction
XSCALE	data scaling
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2018-08-28 
• Released Date: 2019-03-20 
Deposition Author(s): Landel, I., Weisner, J., Mueller, M.P., Scheinpflug, R., Rauh, D.

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Funding Organization	Location	Grant Number
German Federal Ministry for Education and Research	Germany	BMBF 01GS08104
German Federal Ministry for Education and Research	Germany	01ZX1303C

Revision History  

• Version 1.0: 2019-03-20
  Type: Initial release
  
• Version 1.1: 2019-05-15
  Changes: Data collection, Database references