L-amino acid-producing bacterium and a method for producing an L-amino acid
First Claim
Patent Images
1. A method for producing an L-amino acid comprising:
- a) culturing in a medium a bacterium belonging to the family Enterobacteriaceae, which is able to produce an L-amino acid, and has been modified to have a mutation in a yeaS gene selected from the group consisting of;
(I) replacing the amino acid residue at position 28 of SEQ ID NO;
2 with an amino acid residue other than threonine,(II) replacing the amino acid residue at position 137 of SEQ ID NO;
2 with an amino acid residue other than phenylalanine residue,(III) replacing the amino acid residue at position 188 of SEQ ID NO;
2 with an amino acid residue other than leucine, and,(IV) combinations thereof; and
b) collecting the L-amino acid from the medium;
wherein the yeaS gene without said mutation encodes a protein selected from the group consisting of;
(A) a protein comprising the amino acid sequence of SEQ ID NO;
2, and(B) a protein comprising the amino acid sequence of SEQ ID NO;
2, but wherein 1 to 10 amino acid residues are substituted, and the protein has an activity of improving an L-cysteine-producing ability in the bacterium belonging to the family Enterobacteriaceae as compared to a non-modified bacterium when expression of the protein is increased in the bacterium.
1 Assignment
0 Petitions
Accused Products
Abstract
A bacterium belonging to the family Enterobacteriaceae, which has an ability to produce an amino acid such as L-cysteine and has been modified to have specific mutation in the yeas gene, is cultured in a medium, and the L-amino acid is collected from the medium.
10 Citations
15 Claims
-
1. A method for producing an L-amino acid comprising:
-
a) culturing in a medium a bacterium belonging to the family Enterobacteriaceae, which is able to produce an L-amino acid, and has been modified to have a mutation in a yeaS gene selected from the group consisting of; (I) replacing the amino acid residue at position 28 of SEQ ID NO;
2 with an amino acid residue other than threonine,(II) replacing the amino acid residue at position 137 of SEQ ID NO;
2 with an amino acid residue other than phenylalanine residue,(III) replacing the amino acid residue at position 188 of SEQ ID NO;
2 with an amino acid residue other than leucine, and,(IV) combinations thereof; and b) collecting the L-amino acid from the medium; wherein the yeaS gene without said mutation encodes a protein selected from the group consisting of; (A) a protein comprising the amino acid sequence of SEQ ID NO;
2, and(B) a protein comprising the amino acid sequence of SEQ ID NO;
2, but wherein 1 to 10 amino acid residues are substituted, and the protein has an activity of improving an L-cysteine-producing ability in the bacterium belonging to the family Enterobacteriaceae as compared to a non-modified bacterium when expression of the protein is increased in the bacterium. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A bacterium belonging to the family Enterobacteriaceae, which is able to produce an L-amino acid, and has been modified to have a mutation in a yeaS gene selected from the group consisting of:
-
(I) replacing the threonine residue at position 28 of SEQ ID NO;
2 with an amino acid residue other than threonine,(II) replacing the phenylalanine residue at position 137 of SEQ ID NO;
2 with an amino acid residue other than phenylalanine, and(III) replacing the leucine residue at position 188 of SEQ ID NO;
2 with an amino acid residue other than leucine, and,(IV) combinations thereof; and wherein the yeaS gene without said mutation encodes a protein selected from the group consisting of; (A) a protein comprising the amino acid sequence of SEQ ID NO;
2, and(B) a protein comprising the amino acid sequence of SEQ ID NO;
2, but wherein 1 to 10 amino acid residues are substituted, and the protein has an activity of improving the ability to produce L-cysteine when overexpressed in a bacterium belonging to the family Enterobacteriaceae as compared to a bacterium in which the protein is not overexpressed. - View Dependent Claims (14)
-
-
15. A DNA which encodes a protein selected from the group consisting of:
-
(A) a protein comprising the amino acid sequence of SEQ ID NO;
2, and(B) a protein comprising the amino acid sequence of SEQ ID NO;
2, but wherein 1 to 10 amino acid residues are substituted, and the protein has an activity of improving the ability to produce L-cysteine when overexpressed in a bacterium belonging to the family Enterobacteriaceae as compared to a bacterium in which the protein is not overexpressed,wherein the protein has a mutation selected from the group consisting of; (I) replacing the threonine residue at position 28 of SEQ ID NO;
2 with an amino acid residue other than threonine,(II) replacing the phenylalanine residue at position 137 of SEQ ID NO;
2 with an amino acid residue other than phenylalanine,(III) replacing the leucine residue at position 188 of SEQ ID NO;
2 with an amino acid residue other than leucine.
-
Specification