Process for preparing enantiomer-enriched alpha-hydroxycarboxylic acids and amides
The present invention describes an enzymatic process for preparing enantiomer-enriched α-hydroxycarboxylic acids and amides which comprises, in one step, the conversion of a carbonyl compound to the corresponding acid/amides via the intermediate stage of a cyanohydrin. The invention also provides a reaction system operating in such a way and a whole-cell catalyst that is advantageous for use for this reaction.
1 - 11 . (canceled)
12 . A method for preparing an enantiomer-enriched α-hydroxycarboxylic acid or an enantiomer-enriched α-hydroxycarboxylic amide, comprising reacting a cyanide donor with an aldehyde or ketone in the presence of an oxynitrilase and either a nitrilase or a nitrite hydratase.
13 . The method of claim 12 , wherein, said cyanide donor is hydrogen cyanide.
14 . The method of claim 12 , wherein said cyanide donor is reacted with said aldehyde or ketone in the presence of an oxynitrilase and a nitrilase.
15 . The method of claim 12 , wherein said cyanide donor is reacted with said aldehyde or ketone in the presence of an oxynitrilase and nitrile hydratase.
16 . The method of claim 15 , wherein, in addition to said oxynitrilase and nitrile hydratase, an amidase is present.
17 . The process of claim 12 , wherein said oxynitrilase is selected from the group consisting of Sorghum bicolor, Hevea brasiliensis, Mannihot esculenta and almond kernels.
18 . The process claim 14 , wherein said nitrilase is from an organism selected from either a strain of Rhodococcus or Alcaligenes faecalis.
19 . The process of claim 15 , wherein said nitrile hydratase is from an organism selected from the group consisting of: Rhodococcus spec., Rhodococcus rhodochrous and Rhodococcus erythropolis.
20 . The process of claim 12 , wherein said cyanide donor is reacted with said aldehyde or ketone at a temperature of 20-40° C.
21 . The process of claim 12 , wherein:
a) said oxynitrilase is selected from the group consisting of Sorghum bicolor, Hevea brasiliensis, Mannihot esculenta and almond kernels;
b) said nitrilase is from an organism selected from either a strain of Rhodococcus or Alcaligenes faecalis ; and
c) said nitrile hydratase is from an organism selected from the group consisting of: Rhodococcus spec., Rhodococcus rhodochrous and Rhodococcus erythropolis.
22 . An enzymatic reaction composition comprising an oxynitrilase, a nitrilase or a nitrile hydratase, water, a cyanide donor and an aldehyde or a ketone.
23 . The enzymatic reaction composition of claim 22 , wherein said composition comprises an oxynitrilase, a nitrilase, water, a cyanide donor and an aldehyde or a ketone.
24 . The enzymatic reaction composition of claim 22 , wherein wherein said composition comprises an oxynitrilase, a nitrile hydratase, water, a cyanide donor and an aldehyde or a ketone.
25 . The enzymatic reaction composition of claim 24 , further comprising an amidase.
26 . The enzymatic reaction composition of claim 22 , wherein:
a) said oxynitrilase is selected from the group consisting of Sorghum bicolor, Hevea brasiliensis, Mannihot esculenta and almond kernels;
b) said nitrilase is from an organism selected from either a strain of Rhodococcus or Alcaligenes faecalis ; and
c) said nitrile hydratase is from an organism selected from the group consisting of: Rhodococcus spec., Rhodococcus rhodochrous and Rhodococcus erythropolis.
27 . A cell capable of serving as a whole-cell catalyst, wherein said cell comprises a cloned gene encoding an oxynitrilase and a cloned gene encoding either a nitrilase or a nitrile hydratase.
28 . The cell of claim 27 , wherein said cell comprises a cloned gene encoding an oxynitrilase and a cloned gene encoding a nitrilase.
29 . The cell of claim 27 , wherein said cell comprises a cloned gene encoding an oxynitrilase and a cloned gene encoding nitrile hydratase.
30 . The cell of claim 29 , further comprising a cloned gene encoding an amidase.
31 . The cell of claim 27 , wherein:
a) said oxynitrilase is selected from the group consisting of Sorghum bicolor, Hevea brasiliensis, Mannihot esculenta and almond kernels;
b) said nitrilase is from an organism selected from either a strain of Rhodococcus or Alcaligenes faecalis ; and
c) said nitrile hydratase is from an organism selected from the group consisting of: Rhodococcus spec., Rhodococcus rhodochrous and Rhodococcus erythropolis.