Three-dimensional structure of a transglutaminase: human blood coagulation factor XIII

Proc Natl Acad Sci U S A. 1994 Jul 19;91(15):7296-300. doi: 10.1073/pnas.91.15.7296.

Abstract

Mechanical stability in many biological materials is provided by the crosslinking of large structural proteins with gamma-glutamyl-epsilon-lysyl amide bonds. The three-dimensional structure of human recombinant factor XIII (EC 2.3.2.13 zymogen; protein-glutamine:amine gamma-glutamyltransferase a chain), a transglutaminase zymogen, has been solved at 2.8-A resolution by x-ray crystallography. This structure shows that each chain of the homodimeric protein is folded into four sequential domains. A catalytic triad reminiscent of that observed in cysteine proteases has been identified in the core domain. The amino-terminal activation peptide of each subunit crosses the dimer interface and partially occludes the opening of the catalytic cavity in the second subunit, preventing substrate binding to the zymogen. A proposal for the mechanism of activation by thrombin and calcium is made that details the structural events leading to active factor XIIIa'.

Publication types

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

MeSH terms

  • Catalysis
  • Conserved Sequence
  • Crystallography, X-Ray
  • Enzyme Activation
  • Humans
  • Protein Conformation
  • Protein Folding
  • Transglutaminases / chemistry*
  • Transglutaminases / metabolism

Substances

  • Transglutaminases