1BH0

STRUCTURE OF A GLUCAGON ANALOG


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure-function studies on positions 17, 18, and 21 replacement analogues of glucagon: the importance of charged residues and salt bridges in glucagon biological activity.

Sturm, N.S.Lin, Y.Burley, S.K.Krstenansky, J.L.Ahn, J.M.Azizeh, B.Y.Trivedi, D.Hruby, V.J.

(1998) J.Med.Chem. 41: 2693-2700

  • DOI: 10.1021/jm980084a

  • PubMed Abstract: 
  • We have designed and synthesized eight compounds 2-9 which incorporate various amino acid residues in positions 17, 18, and 21 of the glucagon molecule: 2, [Lys17]glucagon amide; 3, [Lys18]glucagon amide; 4, [Nle17,Lys18,Glu21]glucagon amide; 5, [Orn ...

    We have designed and synthesized eight compounds 2-9 which incorporate various amino acid residues in positions 17, 18, and 21 of the glucagon molecule: 2, [Lys17]glucagon amide; 3, [Lys18]glucagon amide; 4, [Nle17,Lys18,Glu21]glucagon amide; 5, [Orn17,18, Glu21]glucagon amide; 6, [d-Arg17]glucagon; 7, [d-Arg18]glucagon; 8, [d-Phe17]glucagon; and 9, [d-Phe18]glucagon. Compared to glucagon (IC50 = 1.5 nM), analogues 2-9 were found to have binding affinity IC50 values (in nM) of 0.7, 4.1, 1.0, 2.0, 5.0, 25.0, 43.0, and 32.0, respectively. When these compounds were tested for their ability to stimulate adenylate cyclase (AC) activity, they were found to be full or partial agonists having maximum stimulation values of 100, 100, 100, 100, 87, 78, 94, and 100%, respectively. On the basis of the X-ray crystal structure of [Lys17,18,Glu21]glucagon amide reported here, the ability to form a salt bridge between Lys18 and Glu21 is probably key to their increased binding and second messenger activities. Among the eight analogues synthesized here, only analogue 4 preserves the ability to form a salt bridge between Lys18 and Glu21. However, since these modifications are minor they do not seem to change the amphiphilic character of the C-terminus, allowing these analogues to reach 78-100% stimulation in the adenylate cyclase assay. Biological data from analogues 6-9 supports the idea that position 18 of glucagon may influence binding only, while position 17 may influence both receptor recognition and transduction.


    Organizational Affiliation

    Department of Chemistry, University of Arizona, Tucson, Arizona 85721, Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10021, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GLUCAGON
A
29Homo sapiensGene Names: GCG
Find proteins for P01275 (Homo sapiens)
Go to Gene View: GCG
Go to UniProtKB:  P01275
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • Space Group: P 21 3
Unit Cell:
Length (Å)Angle (°)
a = 47.900α = 90.00
b = 47.900β = 90.00
c = 47.900γ = 90.00
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORphasing
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1998-11-04
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance