A novel method of producing high-purity hydroxy-L-pipecolic acids in an efficient and inexpensive manner while suppressing the production of hydroxy-L-proline is provided. The method includes allowing an L-pipecolic acid hydroxylase, a microorganism or cell having the ability to produce the enzyme, a processed product of the microorganism or cell, and/or a culture liquid comprising the enzyme and obtained by culturing the microorganism or cell, to act on L-pipecolic acid as a substrate in the presence of 2-oxoglutaric acid and ferrous ion, wherein the L-pipecolic acid hydroxylase has the properties: (1) the enzyme can act on L-pipecolic acid in the presence of 2-oxoglutaric acid and ferrous ion to add a hydroxy group to the carbon atom at positions 3, 4, and/or 5 of L-pipecolic acid; and (2) the enzyme has a catalytic efficiency (kcat/Km) with L-proline that is equal to or less than 7 times the catalytic efficiency (kcat/Km) with L-pipecolic acid.

A method of producing high-purity hydroxy-L-pipecolic acids that includes allowing an L-pipecolic acid hydroxylase, a microorganism or cell having the ability to produce the enzyme, a processed product of the microorganism or cell, and/or a culture liquid comprising the enzyme and obtained by culturing the microorganism or cell, to act on L-pipecolic acid as a substrate in the presence of 2-oxoglutaric acid and ferrous ion, wherein the L-pipecolic acid hydroxylase (1) acts on L-pipecolic acid in the presence of 2-oxoglutaric acid and ferrous ion to add a hydroxy group to the carbon atom at positions 3, 4, and/or 5 of L-pipecolic acid; and (2) has a catalytic efficiency (kcat/Km) with L-proline that is equal to or less than 7 times the catalytic efficiency (kcat/Km) with L-pipecolic acid.

A novel method of producing high-purity hydroxy-L-pipecolic acids in an efficient and inexpensive manner while suppressing the production of hydroxy-L-proline is provided. The method includes allowing an L-pipecolic acid hydroxylase, a microorganism or cell having the ability to produce the enzyme, a processed product of the microorganism or cell, and/or a culture liquid comprising the enzyme and obtained by culturing the microorganism or cell, to act on L-pipecolic acid as a substrate in the presence of 2-oxoglutaric acid and ferrous ion, wherein the L-pipecolic acid hydroxylase has the properties: (1) the enzyme can act on L-pipecolic acid in the presence of 2-oxoglutaric acid and ferrous ion to add a hydroxy group to the carbon atom at positions 3, 4, and/or 5 of L-pipecolic acid; and (2) the enzyme has a catalytic efficiency (kcat/Km) with L-proline that is equal to or less than 7 times the catalytic efficiency (kcat/Km) with L-pipecolic acid.

A novel method of producing high-purity hydroxy-L-pipecolic acids in an efficient and inexpensive manner while suppressing the production of hydroxy-L-proline is provided. The method includes allowing an L-pipecolic acid hydroxylase, a microorganism or cell having the ability to produce the enzyme, a processed product of the microorganism or cell, and/or a culture liquid comprising the enzyme and obtained by culturing the microorganism or cell, to act on L-pipecolic acid as a substrate in the presence of 2-oxoglutaric acid and ferrous ion, wherein the L-pipecolic acid hydroxylase has the properties: (1) the enzyme can act on L-pipecolic acid in the presence of 2-oxoglutaric acid and ferrous ion to add a hydroxy group to the carbon atom at positions 3, 4, and/or 5 of L-pipecolic acid; and (2) the enzyme has a catalytic efficiency (kcat/Km) with L-proline that is equal to or less than 7 times the catalytic efficiency (kcat/Km) with L-pipecolic acid.

A novel method of producing high-purity hydroxy-L-pipecolic acids in an efficient and inexpensive manner while suppressing the production of hydroxy-L-proline is provided. The method includes allowing an L-pipecolic acid hydroxylase, a microorganism or cell having the ability to produce the enzyme, a processed product of the microorganism or cell, and/or a culture liquid comprising the enzyme and obtained by culturing the microorganism or cell, to act on L-pipecolic acid as a substrate in the presence of 2-oxoglutaric acid and ferrous ion, wherein the L-pipecolic acid hydroxylase has the properties: (1) the enzyme can act on L-pipecolic acid in the presence of 2-oxoglutaric acid and ferrous ion to add a hydroxy group to the carbon atom at positions 3, 4, and/or 5 of L-pipecolic acid; and (2) the enzyme has a catalytic efficiency (kcat/Km) with L-proline that is equal to or less than 7 times the catalytic efficiency (kcat/Km) with L-pipecolic acid.

A method of producing high-purity hydroxy-L-pipecolic acids that includes allowing an L-pipecolic acid hydroxylase, a microorganism or cell having the ability to produce the enzyme, a processed product of the microorganism or cell, and/or a culture liquid comprising the enzyme and obtained by culturing the microorganism or cell, to act on L-pipecolic acid as a substrate in the presence of 2-oxoglutaric acid and ferrous ion, wherein the L-pipecolic acid hydroxylase (1) acts on L-pipecolic acid in the presence of 2-oxoglutaric acid and ferrous ion to add a hydroxy group to the carbon atom at positions 3, 4, and/or 5 of L-pipecolic acid; and (2) has a catalytic efficiency (kcat/Km) with L-proline that is equal to or less than 7 times the catalytic efficiency (kcat/Km) with L-pipecolic acid.

The present disclosure belongs to the technical field of enzyme engineering and genetic engineering, and relates to dioxygenase mutants and use thereof in synthesizing (2S,3R)-3-hydroxypipecolic acid. By mutating arginine at position 97 and asparagine at position 43 of the L-proline-3-hydroxylase, the present disclosure makes the specific activity of R97M/N43T up to 2.42 times that of wild-type (WT) enzyme; after conditions are optimized, R97M/N43T achieves a molar yield of 8.82 mM at a substrate concentration of 10 mM under crude enzyme conditions, with a molar yield rate of 88%, which is 4.11 times that of the wild-type enzyme, and a yield of (2S,3R)-3-hydroxypipecolic acid produced by R97M/N43T catalyzing the L-pipecolic acid is 1278 mg.Math.L.sup.1. The mutant with improved catalytic efficiency toward the L-pipecolic acid in the present disclosure is more suitable for research on the production of (2S,3R)-3-hydroxypipecolic acid.

By mutating arginine at position 97 and asparagine at position 43 of a wild type L-proline-3-hydroxylase, a mutated L-proline-3-hydroxylase is obtained. The mutated L-proline-3-hydroxylase comprises a variant of the wild-type L-proline-3-hydroxylase having SEQ ID NO:1, which comprises a substitution of the arginine corresponding to position 97 (R97) of SEQ ID NO:1 and a substitution of the asparagine corresponding to position 43 (N43) of SEQ ID NO:1; wherein the amino acid substituted into the mutated L-proline-3-hydroxylase at position R97 is methionine, and wherein the amino acid substituted into the mutated L-proline-3-hydroxylase at position N43 is selected from the group consisting of threonine (T), alanine (A), valine (V), serine(S), aspartic acid (D), and lysine (K).