L-amino acid producing bacterium

Patent metadata

Field	Value
Publication number	US-9376695-B2
Application number	US-23870408-A
Country	US
Kind code	B2
Filing date	Sep 26, 2008
Priority date	Sep 27, 2007
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

A method for producing an L-amino acid is described, for example, L-phenylalanine and L-histidine, by fermentation using a bacterium of the Enterobacteriaceae family, wherein the bacterium has been modified by attaching a DNA fragment able to be transcribed encoding the peptide represented in SEQ ID NO: 2, or a variant thereof, particularly a portion of the ssrA gene, to the 3′-end of gene encoding for the bacterial enzyme, which influences on the L-amino acid biosynthesis, such as chorismate mutase/prephenate dehydrogenase or phosphoglucose isomerase.

First claim

We claim:

1. A recombinant L-amino acid producing Escherichia coli bacterium having a DNA comprising:
A) a gene selected from the group consisting of tyrA, pheA, pgi, ilvE, ilvA, tdcB, sdaA, sdaB, argA, argG, proB, thrB, and combinations thereof, and
B) a DNA fragment able to be transcribed and encoding the peptide of SEQ ID NO: 2, or a variant thereof consisting of a deletion, insertion, substitution, or addition of 1 amino acid as compared to SEQ ID NO: 2,
wherein said DNA fragment of B) is attached to the 3′ end of said gene of A) and consequently enhances production of an L-amino acid.

2. The bacterium of claim 1 , wherein said bacterium is an L-phenylalanine producing bacterium.

3. The bacterium of claim 1 , wherein said gene is tyrA, which encodes the bifunctional enzyme chorismate mutase/prephenate dehydrogenase.

4. The bacterium of claim 1 , wherein said bacterium is an L-histidine producing bacterium.

5. The bacterium of claim 1 , wherein said gene is pgi which encodes a phosphoglucose isomerase enzyme.

6. A method for producing an L-amino acid comprising cultivating the bacterium according to claim 1 in a culture medium, and isolating the L-amino acid from the culture medium.

7. The method according to claim 6 , wherein said L-amino acid is L-phenylalanine.

8. The method according to claim 6 , wherein said L-amino acid is L-histidine.

9. The bacterium of claim 1 , wherein the variant is the peptide of SEQ ID NO: 15.

Assignees

• Shakulov Rustem Saidovich
• Klyachko Elena Vitalievna
• Doroshenko Vera Georgievna
• Airikh Larisa Gotlibovna
• Ajinomoto Kk

Inventors

• Shakulov Rustem Saidovich
• Klyachko Elena Vitalievna
• Doroshenko Vera Georgievna
• Airikh Larisa Gotlibovna

Classifications

• C12N9/92

  Glucose isomerase {(5.3.1.5; 5.3.1.9; 5.3.1.18)} · CPC title

• C12N9/90

  Isomerases (5.) · CPC title

• C12P21/02 Primary

  having a known sequence of two or more amino acids, e.g. glutathione · CPC title

• C12Y504/99005

  Chorismate mutase (5.4.99.5) · CPC title

• C12Y503/01009

  Glucose-6-phosphate isomerase (5.3.1.9) · CPC title