6NZN

Dimer-of-dimer amyloid fibril structure of glucagon


Experimental Data Snapshot

  • Method: SOLID-STATE NMR
  • Conformers Calculated: 700 
  • Conformers Submitted: 10 
  • Selection Criteria: target function 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

The peptide hormone glucagon forms amyloid fibrils with two coexisting beta-strand conformations.

Gelenter, M.D.Smith, K.J.Liao, S.Y.Mandala, V.S.Dregni, A.J.Lamm, M.S.Tian, Y.Xu, W.Pochan, D.J.Tucker, T.J.Su, Y.Hong, M.

(2019) Nat Struct Mol Biol 26: 592-598

  • DOI: 10.1038/s41594-019-0238-6
  • Primary Citation of Related Structures:  
    6NZN

  • PubMed Abstract: 
  • Glucagon and insulin maintain blood glucose homeostasis and are used to treat hypoglycemia and hyperglycemia, respectively, in patients with diabetes. Whereas insulin is stable for weeks in its solution formulation, glucagon fibrillizes rapidly at the acidic pH required for solubility and is therefore formulated as a lyophilized powder that is reconstituted in an acidic solution immediately before use ...

    Glucagon and insulin maintain blood glucose homeostasis and are used to treat hypoglycemia and hyperglycemia, respectively, in patients with diabetes. Whereas insulin is stable for weeks in its solution formulation, glucagon fibrillizes rapidly at the acidic pH required for solubility and is therefore formulated as a lyophilized powder that is reconstituted in an acidic solution immediately before use. Here we use solid-state NMR to determine the atomic-resolution structure of fibrils of synthetic human glucagon grown at pharmaceutically relevant low pH. Unexpectedly, two sets of chemical shifts are observed, indicating the coexistence of two β-strand conformations. The two conformations have distinct water accessibilities and intermolecular contacts, indicating that they alternate and hydrogen bond in an antiparallel fashion along the fibril axis. Two antiparallel β-sheets assemble with symmetric homodimer cross sections. This amyloid structure is stabilized by numerous aromatic, cation-π, polar and hydrophobic interactions, suggesting mutagenesis approaches to inhibit fibrillization could improve this important drug.


    Organizational Affiliation

    Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA. meihong@mit.edu.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Glucagon
A, B, C, D, E, F, G, H
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P
29Homo sapiensMutation(s): 0 
Gene Names: GCG
UniProt & NIH Common Fund Data Resources
Find proteins for P01275 (Homo sapiens)
Explore P01275 
Go to UniProtKB:  P01275
PHAROS:  P01275
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLID-STATE NMR
  • Conformers Calculated: 700 
  • Conformers Submitted: 10 
  • Selection Criteria: target function 
  • OLDERADO: 6NZN Olderado

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)United States1F31AI133989

Revision History  (Full details and data files)

  • Version 1.0: 2019-06-05
    Type: Initial release
  • Version 1.1: 2019-06-26
    Changes: Data collection, Database references
  • Version 1.2: 2019-07-10
    Changes: Data collection, Database references
  • Version 1.3: 2019-07-17
    Changes: Data collection, Database references
  • Version 1.4: 2019-12-18
    Changes: Author supporting evidence, Data collection