NOVEL 7 BETA-HYDROXYSTEROID DEHYDROGENASE MUTANTS AND PROCESS FOR THE PREPARATION OF URSODEOXYCHOLIC ACID

摘要

The invention relates to novel 7&bgr;-hydroxysteroid dehydrogenase mutants, to the sequences which encode these enzyme mutants, to processes for the preparation of the enzyme mutants and to their use in enzymatic reactions of cholic acid compounds, in particular in the preparation of ursodeoxycholic acid (UDCS). The invention also relates to novel processes for the synthesis of UDCS using the enzyme mutants; and to the preparation of UDCS using recombinant, multiply-modified microorganisms.