Biological Assembly 1  

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

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 12-mer - A6B6 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 12-mer - A6B3C1D1E1 Local Symmetry: Cyclic - C3  (3D View)
Local Stoichiometry: Homo 6-mer - B6 

Local Symmetry: Cyclic - C3  (3D View)
Local Stoichiometry: Homo 6-mer - B6 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: isothermal titration calorimetry, assay for oligomerization

Macromolecule Content

• Total Structure Weight: 34.91 kDa 
• Atom Count: 300 
• Modelled Residue Count: 300 
• Deposited Residue Count: 306 
• Unique protein chains: 2

6JR3

Crystal structure of insulin hexamer fitted into cryo EM density map where each dimer was kept as rigid body

• PDB DOI: 10.2210/pdb6JR3/pdb
• EM Map EMD-9878:EMDBEMDataResource

• Classification: HORMONE
• Organism(s): Homo sapiens
• Expression System: Saccharomyces cerevisiae
• Mutation(s): No 


• Deposited: 2019-04-02 Released: 2020-04-22 
• Deposition Author(s): Sengupta, J., Pathak, B.K., Bhakta, S.
• Funding Organization(s): Department of Biotechnology (India), Department of Science & Technology (India), Council of Scientific & Industrial Research

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 14.5 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Resveratrol as a nontoxic excipient stabilizes insulin in a bioactive hexameric form.

Pathak, B.K., Das, D., Bhakta, S., Chakrabarti, P., Sengupta, J.

(2020) J Comput Aided Mol Des 34: 915-927

• PubMed: 32270361 
• DOI: 10.1007/s10822-020-00311-3
• Primary Citation of Related Structures:  
  6JR3


• PubMed Abstract: 
  

Insulin aggregation is the leading cause of considerable reduction in the amount of active drug molecules in liquid formulations manufactured for diabetes management. Phenolic compounds, such as phenol and m-cresol, are routinely used to stabilize insulin in a hexameric form during its commercial preparation. However, long term usage of commercial insulin results in various adverse secondary responses, for which toxicity of the phenolic excipients is primarily responsible. In this study we aimed to find out a nontoxic insulin stabilizer. To that end, we have selected resveratrol, a natural polyphenol, as a prospective nontoxic insulin stabilizer because of its structural similarity with commercially used phenolic compounds. Atomic force microscopy visualization of resveratrol-treated human insulin revealed that resveratrol has a unique ability to arrest hINS in a soluble oligomeric form having discrete spherical morphology. Most importantly, resveratrol-treated insulin is nontoxic for HepG2 cells and it effectively maintains low blood glucose in a mouse model. Cryo-electron microscopy revealed 3D morphology of resveratrol-stabilized insulin that strikingly resembles crystal structures of insulin hexamer formulated with m-cresol. Significantly, we found that, in a condition inductive to amyloid fibrillation at physiological pH, resveratrol is capable of stabilizing insulin more efficiently than m-cresol. Thus, this study describes resveratrol as an effective nontoxic natural molecule that can be used for stabilizing insulin in a bioactive oligomeric form during its commercial formulation.

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Organizational Affiliation: 

Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India. [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Insulin A chain	A, C, H [auth E], F [auth G], I, K	21	Homo sapiens	Mutation(s): 0  Gene Names: INS
UniProt & NIH Common Fund Data Resources
Find proteins for P01308 (Homo sapiens) Explore P01308  Go to UniProtKB:  P01308
PHAROS:  P01308

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Insulin B chain	B, D, G [auth F], E [auth H], J, L	30	Homo sapiens	Mutation(s): 0  Gene Names: INS
UniProt & NIH Common Fund Data Resources
Find proteins for P01308 (Homo sapiens) Explore P01308  Go to UniProtKB:  P01308
PHAROS:  P01308

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 14.5 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2019-04-02 
• Released Date: 2020-04-22 
Deposition Author(s): Sengupta, J., Pathak, B.K., Bhakta, S.

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Funding Organization	Location	Grant Number
Department of Biotechnology (India)	India	--
Department of Science & Technology (India)	India	--
Council of Scientific & Industrial Research	India	--

Revision History  

• Version 1.0: 2020-04-22
  Type: Initial release
  
• Version 1.1: 2020-04-29
  Changes: Database references
• Version 1.2: 2020-07-08
  Changes: Database references