Analysis of the domain structure of elongation factor-2 kinase by mutagenesis

FEBS Lett. 1999 Aug 27;457(2):189-92. doi: 10.1016/s0014-5793(99)01034-0.


A number of elongation factor-2 kinase (eEF-2K) mutants were constructed to investigate features of this kinase that may be important in its activity. Typical protein kinases possess a highly conserved lysine residue in subdomain II which follows the GXGXXG motif of subdomain I. Mutation of two lysine residues, K340 and K346, which follow the GXGXXG motif in eEF-2K had no effect on activity, showing that such a lysine residue is not important in eEF-2K activity. Mutation of a conserved pair of cysteine residues C-terminal to the GXGXXG sequence, however, completely inactivated eEF-2K. The eEF-2K CaM binding domain was localised to residues 77-99 which reside N-terminal to the catalytic domain. Tryptophan 84 is an important residue within this domain as mutation of this residue completely abolishes CaM binding and eEF-2K activity. Removal of approximately 130 residues from the C-terminus of eEF-2K completely abolished autokinase activity; however, removal of only 19 residues inhibited eEF-2 kinase activity but not autokinase activity, suggesting that a short region at the C-terminal end may be important in interacting with eEF-2. Likewise, removal of between 75 and 100 residues from the N-terminal end completely abolished eEF-2K activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Calcium-Calmodulin-Dependent Protein Kinases / chemistry*
  • Calcium-Calmodulin-Dependent Protein Kinases / genetics
  • Calcium-Calmodulin-Dependent Protein Kinases / metabolism
  • Catalysis
  • Cattle
  • Elongation Factor 2 Kinase
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Phosphorylation
  • Protein Conformation
  • Rabbits
  • Sequence Homology, Amino Acid
  • Tryptophan / metabolism


  • Tryptophan
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Elongation Factor 2 Kinase