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

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.

[1]  M. Tusié-Luna,et al.  Expression of 11β-Hydroxysteroid Dehydrogenase Using Recombinant Vaccinia Virus , 1990 .

[2]  C. Monder,et al.  Purification and Characterization of the Corticosteroid 1lβ-Dehydrogenase Component of the Rat Liver 1lβ-Hydroxysteroid Dehydrogenase Complex* , 1988 .

[3]  M Krook,et al.  Characteristics of short-chain alcohol dehydrogenases and related enzymes. , 1991, European journal of biochemistry.

[4]  H. Tai,et al.  Site-directed mutagenesis of the conserved tyrosine 151 of human placental NAD(+)-dependent 15-hydroxyprostaglandin dehydrogenase yields a catalytically inactive enzyme. , 1991, Biochemical and biophysical research communications.

[5]  R. Saiki,et al.  A general method of in vitro preparation and specific mutagenesis of DNA fragments: study of protein and DNA interactions. , 1988, Nucleic acids research.

[6]  P. White,et al.  Cloning and expression of rat cDNA encoding corticosteroid 11 beta-dehydrogenase. , 1989, The Journal of biological chemistry.

[7]  S W Kessler,et al.  Rapid isolation of antigens from cells with a staphylococcal protein A-antibody adsorbent: parameters of the interaction of antibody-antigen complexes with protein A. , 1975, Journal of immunology.

[8]  J. Funder,et al.  Mineralocorticoid action: target tissue specificity is enzyme, not receptor, mediated. , 1988, Science.

[9]  C. Edwards,et al.  Localisation of 11 beta-hydroxysteroid dehydrogenase--tissue specific protector of the mineralocorticoid receptor. , 1988, Lancet.

[10]  P. White,et al.  The human gene for 11 beta-hydroxysteroid dehydrogenase. Structure, tissue distribution, and chromosomal localization. , 1991, The Journal of biological chemistry.

[11]  Z. Krozowski,et al.  11β-Hydroxysteroid dehydrogenase and the short-chain alcohol dehydrogenase (SCAD) superfamily , 1992, Molecular and Cellular Endocrinology.