Tyr-179 and Lys-183 are essential for enzymatic activity of 11 beta-hydroxysteroid dehydrogenase

Biochem Biophys Res Commun. 1992 Oct 15;188(1):222-7. doi: 10.1016/0006-291x(92)92373-6.


Tyr-179 and Lys-183 are likely to be functionally important residues in 11 beta-hydroxysteroid dehydrogenase, as these amino acids are absolutely conserved in all members of the "short chain dehydrogenase" family. We modified these residues by site-directed mutagenesis of rat cDNA and transfected these constructs into CHO cells. A highly but not absolutely conserved residue, Asp-110, was also studied. Mutation of Tyr-179 to Phe or Ser completely abolished enzymatic activity (interconversion of corticosterone and 11-dehydrocorticosterone), as did Lys-183-->Arg. Asp-110-->Asn affected activity only mildly. Tyr-179 and Lys-183 may be directly involved in the catalytic function of this class of enzymes.

Publication types

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

MeSH terms

  • 11-beta-Hydroxysteroid Dehydrogenases
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • CHO Cells
  • Cricetinae
  • Hydroxysteroid Dehydrogenases / genetics*
  • Hydroxysteroid Dehydrogenases / metabolism*
  • Kinetics
  • Lysine*
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed*
  • Oligodeoxyribonucleotides
  • Rats
  • Recombinant Proteins / metabolism
  • Restriction Mapping
  • Transfection
  • Tyrosine*


  • Oligodeoxyribonucleotides
  • Recombinant Proteins
  • Tyrosine
  • Hydroxysteroid Dehydrogenases
  • 11-beta-Hydroxysteroid Dehydrogenases
  • Lysine