Crystal structure of the tenth type III cell adhesion module of human fibronectin

J Mol Biol. 1994 Mar 4;236(4):1079-92. doi: 10.1016/0022-2836(94)90013-2.


The crystal structure of the cell adhesion module of fibronectin (FNIII10) has been determined at 1.8 A resolution. A recombinant fragment corresponding to the tenth type III module of human fibronectin was crystallized in space group P2(1) with a = 30.7, b = 35.1 and c = 37.7 A and beta = 107 degrees. The structure was determined by molecular replacement and refined by least squares methods. The crystallographic R-factor for the final model of the 91 amino acid module plus 56 solvent atoms is 0.18 for 10 to 1.8 A data. The module consists of two layers of beta-sheet, one with three antiparallel strands and the other with four antiparallel strands. The beta-sheets enclose a hydrophobic core of 24 amino acid side-chains. The module contains the RGD cell recognition sequence in a flexible loop connecting two beta-strands. The tertiary structure of the FNIII10 module has been used to develop a structure-based sequence alignment of 17 type III modules in fibronectin based on the striking conservation of homologous hydrophobic residues. A similar pattern of homologous alternating hydrophobic residues is also evident in a comparison of type III modules in proteins unrelated to fibronectin such as cytokine receptors and muscle proteins.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Cell Adhesion Molecules / chemistry
  • Cell Adhesion Molecules / genetics
  • Cloning, Molecular
  • Crystallography, X-Ray
  • Escherichia coli / genetics
  • Fibronectins / chemistry*
  • Fibronectins / genetics
  • Humans
  • Models, Molecular
  • Molecular Sequence Data
  • Molecular Structure
  • Protein Structure, Secondary
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Sequence Homology, Amino Acid
  • Solvents


  • Cell Adhesion Molecules
  • Fibronectins
  • Recombinant Fusion Proteins
  • Solvents