Mutant phosphoenolpyruvate carboxylase, its gene, and production method of amino acid
AssigneeAjinomoto Co., Inc.
InventorsMasakazu Sugimoto, Tomoko Suzuki, Hiroshi Matsui, Katsura Izui
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Abstract
A phosphoenolpyruvate carboxylase gene, which has mutation such as mutation to replace 625th glutamic acid from the N-terminus of phosphoenolpyruvate carboxylase with lysine, mutation to replace 438th arginine from the N-terminus with cysteine and the like, is introduced into Escherichia coli or coryneform bacteria, so as to produce a phosphoenolpyruvate carboxylase which is not substantially inhibited by aspartic acid, thereby amino acid is efficiently produced.
Claims13
A method of producing an amino acid, comprising:
- selecting a microorganism of the genus Escherichia containing a DNA sequence encoding a mutant phosphoenolpyruvate carboxylase desensitized to feedback inhibition by aspartic acid by growing Escherichia microorganisms in the presence of a wild-type phosphoenolpyruvate carboxylase inhibitor selected from the group consisting of 3-bromopyruvate, aspartic acid-.beta.-hydrazide and DL-threo-.beta.-hydroxyaspartic acid;
- culturing a microorganism of the genus Escherichia or coryneform bacteria transformed with the DNA sequence encoding a mutant phosphoenolpyruvate carboxylase in a suitable medium;
- and
- separating from the medium an amino acid selected from the group consisting of L-lysine, L-threonine, L-methionine, L-isoleucine, L-glutamic acid, L-arginine and L-proline.
A method of producing amino acid, comprising:
- cultivating a microorganism belonging to the genus Escherichia or coryneform bacteria in a suitable medium;
- and
- separating, from the medium, an amino acid selected from the group consisting of L-lysine, L-threonine, L-methionine, L-isoleucine, L-glutamic acid, L-arginine and L-proline,
- wherein the microorganism is transformed by allowing a DNA fragment to be integrated in chromosomal DNA or transformed with a recombinant DNA formed by ligating the DNA fragment with a vector DNA capable of autonomously replication in cells of bacteria belonging to the genus Escherichia or coryneform bacteria, wherein the DNA fragment encodes a mutant phosphoenolpyruvate carboxylase originating from a microorganism belonging to the genus Escherichia;
- the mutant phosphoenolpyruvate carboxylase has mutation to desensitize feedback inhibition of the phosphoenolpyruvate carboxylase by aspartic acid;
- and the mutant phosphoenolpyruvate carboxylase has the arginine residue at the 438.sup.th position from the N-terminus mutated to an amino acid residue other than arginine.
A method of producing amino acid, comprising:
- cultivating a microorganism belonging to the genus Escherichia or coryneform bacteria in a suitable medium;
- and
- separating, from the medium, an amino acid selected from the group consisting of L-lysine, L-threonine, L-methionine, L-isoleucine, L-glutamic acid, L-arginine and L-proline,
- wherein the microorganism is transformed by allowing a DNA fragment to be integrated in chromosomal DNA or transformed with a recombinant DNA formed by ligating the DNA fragment with a vector DNA capable of autonomously replication in cells of bacteria belonging to the genus Escherichia or coryneform bacteria;
- the DNA fragment encodes a mutant phosphoenolpyruvate carboxylase originating from a microorganism belonging to the genus Escherichia;
- the mutant phosphoenolpyruvate carboxylase has mutation to desensitize feedback inhibition of the phosphoenolpyruvate carboxylase by aspartic acid;
- and the mutant phosphoenolpyruvate carboxylase has the lysine residue at the 620.sup.th position from the N-terminus mutated to an amino acid residue other than lysine.
Dependencies are inferred from the claim text.