IP Library › Granted Patent US 12,421,533
Granted Patent B2
US 12,421,533 · App. 17/761,157 · Granted Sep 23, 2025

Ean B mutants and their uses

Inventors: Qilin Liao (Nanjing, CN); Jian Zhang (Nanjing, CN)
Assignee: NANJING NUTRABUILDING BIO-TECH CO., LTD.
C12P13/04C12N9/13C12N15/70C12N2800/101
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Quick Facts
Patent No.
US 12,421,533
App. No.
17/761,157
Granted
Sep 23, 2025
Kind
B2
Abstract

Provided herein includes a method for producing ergothioneine, comprising N(α)-trimethyl histidine and an oxidative sulfurizing enzyme mutant. With the mutant enzyme's help, the conversion rate is higher than 30% with the mutant enzyme amount of 8000/g substrate in 24 hours. Disclosed are a nucleic acid encoding the mutant enzyme, an expression vector comprising the nucleic acid, an expressing host comprising the nucleic acid or the expression vector, and the use of the mutant enzyme EanB for producing the ergothioneine.

Claims (13)

1. An EanB enzyme mutant comprising mutation of one or more changes at position 75, 84 or 369 in amino acid sequence of SEQ ID No 1, wherein the mutation is one or two of following changes: (1) I of position 75 is mutated to R; (2) E of position 369 is mutated to P.

2. The EanB enzyme mutant according to claim 1 , wherein the mutant comprises an amino acid sequence of SEQ ID NO: 3, SEQ ID NO: 5, or SEQ ID NO: 7.

3. The EanB enzyme mutant according to claim 2 , wherein the EanB enzyme mutant is encoded by a polynucleotide, wherein the polynucleotide comprises a nucleic acid sequence of SEQ ID NO: 4, SEQ ID NO: 6, or SEQ ID NO: 8.

4. The EanB enzyme mutant according to claim 3 , wherein the polynucleotide is located on an expression vector.

5. The EanB enzyme mutant according to claim 4 , wherein the expression vector is pSH plasmid.

6. The EanB enzyme mutant according to claim 3 , wherein the polynucleotide is included in a host cell.

7. The EanB enzyme mutant according to claim 6 , wherein the host cell is Escherichia coli.

8. An EanB enzyme mutant comprising mutation of one or more changes at position 75, 84 or 369 in amino acid sequence of SEQ ID No 1, and further comprising an amino acid sequence of SEQ ID NO: 3, SEQ ID NO: 5, or SEQ ID NO: 7.

9. The EanB enzyme mutant according to claim 8 , wherein the EanB enzyme mutant is encoded by a polynucleotide, wherein the polynucleotide comprises a nucleic acid sequence of SEQ ID NO: 4, SEQ ID NO: 6, or SEQ ID NO: 8.

10. The EanB enzyme mutant according to claim 9 , wherein the polynucleotide is located on an expression vector.

11. The EanB enzyme mutant according to claim 10 , wherein the expression vector is pSH plasmid.

12. The EanB enzyme mutant according to claim 9 , wherein the polynucleotide is included in a host cell.

13. The EanB enzyme mutant according to claim 12 , wherein the host cell is Escherichia coli.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 24, 2025
From: LIAO, QILIN
To: NANJING NUTRABUILDING BIO-TECH CO., LTD.
Reel/Frame 071821/0315 →
EMPLOYMENT AGREEMENT Recorded Jul 24, 2025
From: ZHANG, JIAN
To: NANJING NUTRABUILDING BIO-TECH CO., LTD.
Reel/Frame 072240/0363 →
Continuity (1)
Related Publication 20230024648A1 · Jan 26, 2023
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