Microorganism producing O-acetyl homoserine and the method of producing O-acetyl homoserine using the same

• US 10,815,509 B2
• Filed: 09/20/2019
• Issued: 10/27/2020
• Est. Priority Date: 06/23/2014
• Status: Active Grant

• Current Assignee: CJ Cheiljedang Corporation (CJ Group)
• Original Assignee: CJ Cheiljedang Corporation (CJ Group)
• Inventors: Kim, Hyun Ah, Seo, Ju Hee, Shin, Yong Uk, Kim, So Young, Kim, Sang Kyoum, Na, Kwang Ho, Bae, Jee Yeon, Son, Sung Kwang, Yoo, Hye Ryun, Choi, Jin Geun
• Primary Examiner(s): Mondesi, Robert B
• Assistant Examiner(s): Epstein, Todd M
• Application Number:
  US16/577,837
• Publication Number:
  US 20200024626A1
• Time in Patent Office: 403 Days
• Field of Search: None
• CPC Class Codes: C12N 15/52 Genes encoding for enzymes or proenzymes
• CPC Class Codes: C12N 9/1029 transferring groups other than amino-acyl groups (2.3.1)
• CPC Class Codes: C12N 9/1205 Phosphotransferases with an alcohol group as acceptor (2.7.1), e.g. protein kinases
• CPC Class Codes: C12N 9/88 Lyases (4.)
• CPC Class Codes: C12P 13/06 Alanine; Leucine; Isoleucine; Serine; Homoserine
• CPC Class Codes: C12Y 203/01031 Homoserine O-acetyltransferase (2.3.1.31)
• CPC Class Codes: C12Y 203/03001 Citrate (Si)-synthase (2.3.3.1)
• CPC Class Codes: C12Y 207/01039 Homoserine kinase (2.7.1.39)
• CPC Class Codes: C12Y 401/01031 Phosphoenolpyruvate carboxylase (4.1.1.31)

Abstract

Disclosed is a microorganism of Escherichia sp. producing O-acetyl homoserine, and a method of producing O-acetyl homoserine in high yield using the microorganism.

Claims

1. A method for producing L-methionine, comprising:

(a) culturing a microorganism of Escherichia sp. producing O-acetyl homoserine,

wherein in the microorganism, the endogenous activity of citrate synthase is attenuated or inactivated, and a homoserine O-acetyltransferase is further introduced or enhanced, or an endogenous homoserine O-succinyltransferase is further modified to a polypeptide having 95% identity or above with SEQ ID NO;

16 and further having mutations at the G111E position and L112T or L112H positions to have the activity of homoserine O-acetyltransferase; and

(b) contacting O-acetyl homoserine produced in step (a) with O-acetyl homoserine sulfhydrylase, or a microorganism having O-acetyl homoserine sulfhydrylase.

2. The method according to claim 1, wherein the microorganism with the attenuated endogenous activity of citrate synthase has an amino acid sequence of SEQ ID NO:

1 or SEQ ID NO;

2.

3. The method according to claim 1, wherein in the microorganism, the activity of cystathionine gamma synthase, homoserine kinase, or both is further attenuated or inactivated compared to their endogenous activities.

4. The method according to claim 1, wherein in the microorganism, the activity of at least one protein selected from the group consisting of phosphoenolpyruvate carboxylase, aspartate aminotransferase, and aspartate semialdehyde dehydrogenase is further introduced or enhanced.

5. The method according to claim 1, wherein the microorganism is Escherichia coli.

6. The method according to claim 1, wherein O-acetyl homoserine sulfhydrylase is derived from Leptospira sp., Chromobacterium sp., or Hyphomonas sp.

7. The method according to claim 1, further comprising adding methylmercaptan as substrate in step (b).

8. The method according to claim 1, further comprising recovering O-acetyl homoserine produced in step (a).

9. The method according to claim 1, further comprising recovering L-methionine produced in step (b).