The present invention relates to a method for the stereo selective production of a trans-diol or a cis-diol or a hydroxyketone comprising the step(s) (i) conversion of a trans-diol or a cis-diol to a hydroxyketone and/or (ii) conversion of a hydroxyketone to a cis-diol or a trans-diol, catalyzed by an enzyme, which is encoded by a nucleic acid sequence of SEQ ID NO: or wherein the enzyme comprises an amino acid sequence of SEQ ID NO: 2. The present invention also relates to the use of an enzyme encoded by a nucleic acid sequence of SEQ ID NO: 1 or wherein the enzyme comprises an amino acid sequence of SEQ ID NO: 2 for the conversion of a trans-diol to a cis-diol or for the conversion of a trans-diol or a cis-diol to a hydroxyketone and/or the conversion of a hydroxyketone to a trans-diol or a cis-diol.

The invention relates to novel 3-hydroxysteroid dehydrogenase mutants, to the sequences which code for these enzyme mutants, to processes for the preparation of the enzyme mutants and to their use in enzymatic conversions of cholic acid compounds, in particular in the preparation of ursodeoxycholic acid (UDCA); subject-matter of the invention is also novel processes for the synthesis of UDCA using enzyme mutants; and the preparation of UDCA using recombinant, multiply modified microorganisms.

The invention provides novel 3α-hydroxysteroid dehydrogenase mutants, sequences that code for these enzyme mutants, methods for producing the enzyme mutants, and the use thereof in enzymatic reactions of cholic acid compounds, and in particular in the production of ursodeoxycholic acid (UDCA). The invention further provides processes for the synthesis of UDCA using the enzyme mutants and the production of UDCA using recombinant microorganisms that have been subjected to multiple modifications.

A method of inhibiting activity or expression of one or more 3α-oxidoreductase enzymes that share a common catalytic site and convert androstanediol to DHT. The method comprises introducing one or more agents into cells that comprise the one or more 3α-oxidoreductase enzymes, wherein said one or more agents: i) inhibit function of one or more of said enzymes; ii) inhibit translation of mRNA encoding said enzymes; iii) disrupt or delete genes encoding said enzymes; or a combination thereof.

The invention relates to novel biocatalytic processes comprising the whole cell reduction of dehydrocholic acid (DHCA) compounds, novel 7-hydroxy steroid dehydrogenase mutants, the sequences coding for these enzyme mutants, methods for producing the enzyme mutants and use thereof in enzymatic conversions of cholic acid compounds, and in particular in the production of ursodesoxycholic acid (UDCA); also a subject of the invention are novel methods for the synthesis of UDCA using the enzyme mutants; and in particular a further improved method for producing UDCA using recombinant whole cell biocatalysts.

The invention provides novel 3-hydroxysteroid dehydrogenase mutants, sequences that code for these enzyme mutants, methods for producing the enzyme mutants, and o the use thereof in enzymatic reactions of cholic acid compounds, and in particular in the production of ursodeoxycholic acid (UDCA). The invention further provides processes for the synthesis of UDCA using the enzyme mutants and the production of UDCA using recombinant microorganisms that have been subjected to multiple modifications.

The invention relates to novel biocatalytic processes comprising the whole cell reduction of dehydrocholic acid (DHCA) compounds, novel 7-hydroxy steroid dehydrogenase mutants, the sequences coding for these enzyme mutants, methods for producing the enzyme mutants and use thereof in enzymatic conversions of cholic acid compounds, and in particular in the production of ursodesoxycholic acid (UDCA); also a subject of the invention are novel methods for the synthesis of UDCA using the enzyme mutants; and in particular a further improved method for producing UDCA using recombinant whole cell biocatalysts.

The present invention relates to a method for the stereo selective production of a trans-diol or a cis-diol or a hydroxyketone comprising the step(s) (i) conversion of a trans-diol or a cis-diol to a hydroxyketone and/or (ii) conversion of a hydroxyketoneto a cis-diol or a trans-diol, catalyzed by an enzyme, which is encoded by a nucleic acid sequence of SEQ ID NO: or wherein the enzyme comprises an amino acid sequence of SEQ ID NO: 2. The present invention also relates to the use of an enzyme encoded by a nucleic acid sequence of SEQ ID NO: 1 or wherein the enzyme comprises an amino acid sequence of SEQ ID NO: 2 for the conversion of a trans-diol to a cis-diol or for the conversion of a trans-diol or a cis-diol to a hydroxy ketone and/or the conversion of a hydroxyketone to a trans-diol or a cis-diol.