Macromolecule Content

• Total Structure Weight: 5794.59 
• Atom Count: 403 
• Residue Count: 51 
• Unique protein chains: 2

1KMF

NMR STRUCTURE OF HUMAN INSULIN MUTANT ILE-A2-ALLO-ILE, HIS-B10-ASP, PRO-B28-LYS, LYS-B29-PRO, 15 STRUCTURES

• DOI: 10.2210/pdb1KMF/pdb

• Classification: HORMONE/GROWTH FACTOR
• Organism(s): Homo sapiens
• Mutation(s): 4 


• Deposited: 2001-12-14 Released: 2002-01-09 
• Deposition Author(s): Xu, B., Hua, Q.X., Nakagawa, S.H., Jia, W., Chu, Y.C., Katsoyannis, P.G., Weiss, M.A.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 15 
• Selection Criteria: structures with the lowest energy 

Literature

Chiral mutagenesis of insulin's hidden receptor-binding surface: structure of an allo-isoleucine(A2) analogue.

Xu, B., Hua, Q.X., Nakagawa, S.H., Jia, W., Chu, Y.C., Katsoyannis, P.G., Weiss, M.A.

(2002) J.Mol.Biol. 316: 435-441

• PubMed: 11866509 
• DOI: 10.1006/jmbi.2001.5377


• PubMed Abstract: 
  

The hydrophobic core of vertebrate insulins contains an invariant isoleucine residue at position A2. Lack of variation may reflect this side-chain's dual contribution to structure and function: Ile(A2) is proposed both to stabilize the A1-A8 alpha-helix and to contribute to a "hidden" functional surface exposed on receptor binding. Substitution of Ile(A2) by alanine results in segmental unfolding of the A1-A8 alpha-helix, lower thermodynamic stability and impaired receptor binding. Such a spectrum of perturbations, although of biophysical interest, confounds interpretation of structure-activity relationships. To investigate the specific contribution of Ile(A2) to insulin's functional surface, we have employed non-standard mutagenesis: inversion of side-chain chirality in engineered monomer allo-Ile(A2)-DKP-insulin. Although the analogue retains native structure and stability, its affinity for the insulin receptor is impaired by 50-fold. Thus, whereas insulin's core readily accommodates allo-isoleucine at A2, its activity is exquisitely sensitive to chiral inversion. We propose that the Ile(A2) side-chain inserts within a chiral pocket of the receptor as part of insulin's hidden functional surface.

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Related Citations: 

• A Cavity-Forming Mutation in Insulin Induces Segmental Unfolding of a Surrounding alpha-Helix
  Xu, B.,Hua, Q.X.,Nakagawa, S.H.,Jia, W.,Chu, Y.C.,Katsoyannis, P.G.,Weiss, M.A.
  (2002) Protein Sci. 11: 104
• Importance of Aliphatic Side-Chain Structure at Positions 2 and 3 of the Insulin A Chain in Insulin-Receptor Interactions
  Nakagawa, S.H.,Tager, H.S.
  (1992) Biochemistry 31: 3204
• Critical Role of the A2 Amino Acid Residue in the Biological Activity of Insulin: [2-Glycine-A]- and [2-Alanine-A]insulins
  Kitagawa, K.,Ogawa, H.,Burke, G.T.,Chanley, J.D.,Katsoyannis, P.G.
  (1984) Biochemistry 23: 1405
• Mapping the Functional Surface of Insulin by Design: Structure and Function of a Novel A-Chain Analogue
  Hua, Q.X.,Hu, S.Q.,Frank, B.H.,Jia, W.,Chu, Y.C.,Wang, S.H.,Burke, G.T.,Katsoyannis, P.G.,Weiss, M.A.
  (1996) J.Mol.Biol. 264: 390




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Organizational Affiliation: 

Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4935, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Insulin	A	21	Homo sapiens	Mutation(s): 1  Gene Names: INS
Find proteins for P01308 (Homo sapiens) Go to Gene View: INS Go to UniProtKB:  P01308

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
Insulin	B	30	Homo sapiens	Mutation(s): 3  Gene Names: INS
Find proteins for P01308 (Homo sapiens) Go to Gene View: INS Go to UniProtKB:  P01308

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
IIL	A	L-PEPTIDE LINKING	C6 H13 N O2		ILE

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 15 
• Selection Criteria: structures with the lowest energy 
• Olderado: 1KMF Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-12-14 
• Released Date: 2002-01-09 
• Deposition Author(s): Xu, B., Hua, Q.X., Nakagawa, S.H., Jia, W., Chu, Y.C., Katsoyannis, P.G., Weiss, M.A.

Revision History 

• Version 1.0: 2002-01-09
  Type: Initial release
• Version 1.1: 2008-04-27
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance