Enzymatic method for producing 2-hydroxy-4-methylmercaptobutanoic acid (MHA)
The invention relates to an enzymatic method for producing 2-hydroxy-4-methylmercaptobutanoic acid from 3-methylthio-propanal (3-methylmercaptopropanal (MMP) or “methional”) and carbon dioxide.
1. A method for producing D- or L-2-hydroxy-4-methylmercaptobutanoic acid (MHA), comprising reacting a mixture comprising: 3-(methylthio)-propanal (methional); carbon dioxide; a decarboxylase (EC 4.1.1); a corresponding cofactor of the decarboxylase; an alcohol dehydrogenase (EC 1.1.1); and NADH or NADPH, to form D- or L-2-hydroxy-4-methylmercaptobutanoic acid (MHA) or a salt thereof.
2. The method of claim 1 , wherein the cofactor comprises thiamine pyrophosphate.
3. The method of claim 1 , wherein the decarboxylase is selected from the group consisting of pyruvate decarboxylase Pdc1, which originates from Saccharomyces cerevisiae , phenylpyruvate decarboxylase Aro10, which originates from Saccharomyces cerevisiae , and branched chain decarboxylase KdcA, which originates from Lactococcus lactis.
4. The method of claim 1 , wherein said method is for producing D-2-hydroxy-4-methylmercapto-butanoic acid (D-MHA), and wherein the alcohol dehydrogenase is a D-hydroxyisocaproate dehydrogenase.
5. The method of claim 4 , wherein the D-hydroxyisocaproate dehydrogenase is D-HicDH from Lactobacillus casei.
6. The method of claim 1 , where said method is for producing L-2-hydroxy-4-methylmercapto-butanoic acid (L-MHA), and wherein the alcohol dehydrogenase is a L-hydroxyisocaproate dehydrogenase.
7. The method of claim 6 , wherein the L-hydroxyisocaproate dehydrogenase is L-HicDH from Lactobacillus confusus.
8. The method of claim 1 , wherein the carbon dioxide is applied to the mixture at a pressure from 10 to 7400 kPa.
9. The method of claim 1 , wherein the mixture further comprises formic acid or a salt thereof and a formate dehydrogenase (EC 1.17.1.9).
10. The method of claim 9 , wherein the formate dehydrogenase is selected from the group consisting of a formate dehydrogenase from Pseudomonas sp. and a formate dehydrogenase from Candida sp.
11. The method of claim 2 , wherein the decarboxylase is selected from the group consisting of pyruvate decarboxylase Pdc1, which originates from Saccharomyces cerevisiae , phenylpyruvate decarboxylase Aro10, which originates from Saccharomyces cerevisiae , and branched chain decarboxylase KdcA, which originates from Lactococcus lactis.
12. The method of claim 11 , wherein said method is for producing D-2-hydroxy-4-methylmercapto-butanoic acid (D-MHA), and wherein the alcohol dehydrogenase is a D-hydroxyisocaproate dehydrogenase.
13. The method of claim 12 , wherein the D-hydroxyisocaproate dehydrogenase is D-HicDH from Lactobacillus casei.
14. The method of claim 13 , wherein the carbon dioxide is applied to the mixture at a pressure from 10 to 7400 kPa.
15. The method of claim 14 , wherein the mixture further comprises formic acid or a salt thereof and a formate dehydrogenase (EC 1.17.1.9).
16. The method of claim 15 , wherein the formate dehydrogenase is selected from the group consisting of a formate dehydrogenase from Pseudomonas sp. and a formate dehydrogenase from Candida sp.
17. The method of claim 2 , where said method is for producing L-2-hydroxy-4-methylmercapto-butanoic acid (L-MHA), and wherein the alcohol dehydrogenase is a L-hydroxyisocaproate dehydrogenase.
18. The method of claim 17 , wherein the L-hydroxyisocaproate dehydrogenase is L-HicDH from Lactobacillus confusus.
19. The method of claim 18 , wherein the decarboxylase is selected from the group consisting of pyruvate decarboxylase Pdc1, which originates from Saccharomyces cerevisiae , phenylpyruvate decarboxylase Aro10, which originates from Saccharomyces cerevisiae , and branched chain decarboxylase KdcA, which originates from Lactococcus lactis.
20. The method of claim 19 , wherein the carbon dioxide is applied to the mixture at a pressure from 10 to 7400 kPa and wherein the mixture further comprises formic acid or a salt thereof and a formate dehydrogenase (EC 1.17.1.9).