1A3P

ROLE OF THE 6-20 DISULFIDE BRIDGE IN THE STRUCTURE AND ACTIVITY OF EPIDERMAL GROWTH FACTOR, NMR, 20 STRUCTURES

Summary for 1A3P

• Entry DOI: 10.2210/pdb1a3p/pdb
• NMR Information: BMRB: 4201
• Descriptor: EPIDERMAL GROWTH FACTOR (1 entity in total)
• Functional Keywords: growth factor, murine epidermal growth factor, disulfide connectivities, egf-like domain
• Biological source: Mus musculus (house mouse)
• Cellular location: Membrane; Single-pass type I membrane protein: P01132
• Total number of polymer chains: 1
• Total formula weight: 4878.40

Authors

Barnham, K.,Torres, A.,Alewood, D.,Alewood, P.,Domagala, T.,Nice, E.,Norton, R. (deposition date: 1998-01-22, release date: 1998-07-29, Last modification date: 2018-03-14)

Primary citation

Barnham, K.J.,Torres, A.M.,Alewood, D.,Alewood, P.F.,Domagala, T.,Nice, E.C.,Norton, R.S.
Role of the 6-20 disulfide bridge in the structure and activity of epidermal growth factor.
Protein Sci., 7:1738-1749, 1998

PubMed Abstract: Two synthetic analogues of murine epidermal growth factor, [Abu6, 20] mEGF4-48 (where Abu denotes amino-butyric acid) and [G1, M3, K21, H40] mEGF1-48, have been investigated by NMR spectroscopy. [Abu6, 20] mEGF4-48 was designed to determine the contribution of the 6-20 disulfide bridge to the structure and function of mEGF. The overall structure of this analogue was similar to that of native mEGF, indicating that the loss of the 6-20 disulfide bridge did not affect the global fold of the molecule. Significant structural differences were observed near the N-terminus, however, with the direction of the polypeptide chain between residues four and nine being altered such that these residues were now located on the opposite face of the main beta-sheet from their position in native mEGF. Thermal denaturation experiments also showed that the structure of [Abu6, 20] mEGF4-48 was less stable than that of mEGF. Removal of this disulfide bridge resulted in a significant loss of both mitogenic activity in Balb/c 3T3 cells and receptor binding on A431 cells compared with native mEGF and mEGF4-48, implying that the structural changes in [Abu6, 20] mEGF4-48, although limited to the N-terminus, were sufficient to interfere with receptor binding. The loss of binding affinity probably arose mainly from steric interactions of the dislocated N-terminal region with part of the receptor binding surface of EGF. [G1, M3, K21, H40] mEGF1-48 was also synthesized in order to compare the synthetic polypeptide with the corresponding product of recombinant expression. Its mitogenic activity in Balb/c 3T3 cells was similar to that of native mEGF and analysis of its 1H chemical shifts suggested that its structure was also very similar to native.

PubMed: 10082370

Experimental method

SOLUTION NMR