L-threonine dehydratase variant and method of producing l-isoleucine using the same

Patent metadata

Field	Value
Publication number	US-12509673-B2
Application number	US-202117440172-A
Country	US
Kind code	B2
Filing date	Apr 21, 2021
Priority date	Jun 26, 2020
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

An L-threonine dehydratase variant is provided that is capable of producing increased yields of the amino acid L-isoleucine when expressed in host organisms and methods of producing increased yields of L-isoleucine using the same.

First claim

The invention claimed is:

1 . An L-threonine dehydratase variant in which an amino acid corresponding to the 381st position of an amino acid sequence of SEQ ID NO: 1 is substituted with a different amino acid,
wherein the L-threonine dehydratase variant comprises a sequence having at least 96% identity with the amino acid sequence of SEQ ID NO:1, and wherein the different amino acid is selected from the group consisting of: alanine, serine, proline, glutamine, valine, isoleucine, and glycine.

2 . The variant of claim 1 , wherein the variant comprises one amino acid sequence selected from the group consisting of amino acid sequences of SEQ ID NOS: 4 to 9.

3 . The variant of claim 1 , wherein the variant is one in which an amino acid corresponding to the 383 rd position of the amino acid sequence of SEQ ID NO: 1 is further substituted with alanine.

4 . The variant of claim 3 , wherein the variant comprises one amino acid sequence selected from the group consisting of amino acid sequences of SEQ ID NOS: 24-29.

5 . A polynucleotide encoding the L-threonine dehydratase variant according to claim 1 .

6 . A microorganism comprising at least one of: the L-threonine dehydratase variant according to claim 1 ; a polynucleotide encoding the variant; and a vector including the polynucleotide.

7 . The microorganism of claim 6 , wherein the microorganism has L-isoleucine producing capability.

8 . The microorganism of claim 6 , wherein the microorganism belongs to the genus Corynebacterium.

9 . The microorganism of claim 6 , wherein the microorganism is Corynebacterium glutamicum.

10 . A method of producing L-isoleucine, the method comprising: culturing a microorganism comprising at least one of: the L-threonine dehydratase variant according to claim 1 , a polynucleotide encoding the variant, and a vector including the polynucleotide; in a culture medium.

11 . The method of claim 10 , further comprising recovering L-isoleucine from the culture medium or the microorganism.

12 . A composition for producing L-isoleucine comprising a microorganism comprising at least one of: the L-threonine dehydratase variant according to claim 1 , a polynucleotide encoding the variant, and a vector including the polynucleotide; or cultures of the microorganism.

13 . The variant of claim 1 , wherein the L-threonine dehydratase variant comprises a sequence having at least 98% identity with the amino acid sequence of SEQ ID NO: 1.

14 . The variant of claim 1 , wherein the L-threonine dehydratase variant comprises a sequence having at least 99% identity with the amino acid sequence of SEQ ID NO: 1.

15 . The variant of claim 1 , wherein the different amino acid is alanine.

16 . The variant of claim 1 , wherein the variant comprises the amino acid sequence of SEQ ID NO: 3.

17 . The variant of claim 3 , wherein the variant comprises the amino acid sequence of SEQ ID NO: 23.

Assignees

• Cj Cheiljedang Corp

Inventors

• Kim Kyungrim
• Lee Imsang
• Kim Heeyeong
• Lee Kwang Woo

Classifications

• C12Y403/01019

  Threonine ammonia-lyase (4.3.1.19) · CPC title

• C12P13/06

  Alanine; Leucine; Isoleucine; Serine; Homoserine · CPC title

• C12N15/77

  for Corynebacterium; for Brevibacterium · CPC title

• C12N15/52

  Genes encoding for enzymes or proenzymes · CPC title

• C12R2001/15

  Corynebacterium · CPC title