公开(公告)号：US20240110173A1

公开(公告)日：2024-04-04

申请号：US18542109

申请日：2023-12-15

Applicant: Jiangnan University

Inventor： Zhiming RAO ,  Jin Han ,  Taowei Yang ,  Meijuan Xu ,  Xian Zhang

IPC: C12N9/88 ,  C12P13/00

CPC classification number: C12N9/88 ,  C12P13/005 ,  C12Y401/01015

Abstract: The invention provides a glutamate decarboxylase mutant with improved pH tolerance and use thereof in synthesis of gamma-aminobutyric acid. The mutant is obtained by mutating glutamate decarboxylase having an amino acid sequence as shown in SEQ ID NO. 3. The enzyme activity of the mutant at pH 6.5 is improved to 178% of the original enzyme (SEQ ID NO. 3). The final yield of 1000 g of substrate fed in batches in a 5L tank for 12 h is up to 688.13 g/L, which is about 52% higher than the productivity of the original glutamate decarboxylase. The final molar conversion rate can reach 98.2%. The invention not only broadens the enzyme activity of GAD under the optimum pH, but also broadens the enzyme activity of GAD under the neutral pH, and enhances the capability of the GAD to synthesize gamma-aminobutyric acid, and therefore is more suitable for industrial production.

公开(公告)号：US20190161779A1

公开(公告)日：2019-05-30

申请号：US16063651

申请日：2016-11-17

Applicant: Jiangnan University

Inventor： Zhiming RAO ,  Junping ZHOU ,  Taowei YANG ,  Xian ZHANG ,  Meijuan XU ,  CaiZhe ZHANG ,  Yunlong QI ,  Junxian ZHENG

IPC: C12P13/04 ,  C12N15/73

Abstract: The present invention discloses a single-cell factory for efficiently synthesizing α-aminobutyric acid and construction and application thereof, which belong to the technical field of microorganisms. The present invention expresses an L-threonine deaminase gene, an L-amino acid dehydrogenase gene and a dehydrogenase gene for providing cofactor NADH cycle in tandem to construct a recombinant Escherichia coli single-cell factory which is used for efficiently synthesizing α-aminobutyric acid. The expression level of the L-threonine deaminase is optimized and controlled by an RBS sequence, so that the problem of transformation inhibition caused by the rapid accumulation of an intermediate product ketobutyric acid is solved, moreover, the expression level of the dehydrogenase for providing cofactor NADH cycle is optimized and controlled by a promoter and an RBS sequence, consequently, the NADH regeneration rate is increased, and ultimately, yield is increased. Utilizing the single-cell factory to carry out whole-cell transformation can reduce obstacles to substances getting in and out, increase the transformation rate and promote the intracellular cycle of cofactors without requiring exogenous addition, and the cost is low. Within 20 h, the yield of the recombinant Escherichia coli single-cell factory in a 5 L fermentation tank is 204 g·L−1, the space-time yield is 10.2 g·L−1·h−1, and a practical effective strategy is provided for industrialized production

公开(公告)号：US20240158737A1

公开(公告)日：2024-05-16

申请号：US18420028

申请日：2024-01-23

Applicant: JIANGNAN UNIVERSITY

Inventor： Zhiming RAO ,  Yanan HAO ,  Meijuan XU ,  Xuewei PAN ,  Jiajia YOU ,  Taowei YANG ,  Xian ZHANG ,  Mingling SHAO

IPC: C12N1/20 ,  C12N9/10 ,  C12N9/88 ,  C12N15/70 ,  C12P13/08

CPC classification number: C12N1/205 ,  C12N9/1096 ,  C12N9/88 ,  C12N15/70 ,  C12P13/08 ,  C12Y206/01042 ,  C12Y402/01009 ,  C12Y402/01012 ,  C12R2001/19

Abstract: The invention provides an Escherichia coli for synthesizing L-valine, a construction method and use thereof. The Escherichia coli of the invention is designated as Escherichia coli W3110 and was deposited in China Center for Type Culture Collection (Address: Bayi Road, Wuchang District, Wuhan City, Hubei Province) under the Accession No. CCTCC M 2022293 on Mar. 18, 2022. The recombinant Escherichia coli takes Escherichia coli as a starting strain, and a transcription regulation factor is overexpressed to obtain a recombinant Escherichia coli. The recombinant Escherichia coli for synthesizing L-valine of the invention is fermented in a 5 L fermentor with trace dissolved oxygen to test strains, the yield of L-valine reaches 112 g/L, and the OD of the bacterium is 104.

公开(公告)号：US20240002867A1

公开(公告)日：2024-01-04

申请号：US17935466

申请日：2022-09-26

Applicant: Jiangnan University

Inventor： Zhiming RAO ,  Jiajia YOU ,  Taowei YANG ,  Xuewei PAN ,  Xian ZHANG ,  Meijuan XU

IPC: C12N15/75 ,  C12N9/04 ,  C12N9/90 ,  C12N9/88 ,  C12N9/92 ,  C12N1/20 ,  C07K14/32 ,  C12P25/00

CPC classification number: C12N15/75 ,  C12N9/0006 ,  C12N9/90 ,  C12N9/88 ,  C12N9/92 ,  C12N1/205 ,  C07K14/32 ,  C12P25/00 ,  C12Y101/01049 ,  C12Y503/01006 ,  C12Y401/99012 ,  C12Y503/01009 ,  C12R2001/125

Abstract: The present disclosure provides a Bacillus subtilis strain, a recombinant B. subtilis strain and use thereof, belongs to the technical field of microbial fermentation. B. subtilis strain RF1-6 provided by the present disclosure is a mutant strain with the highest riboflavin yield screened by gene modification and mutagenesis using a high riboflavin-producing strain RF1 as a starting strain, deposited at China Center for Type Culture Collection (CCTCC) under accession number M 2022565. Riboflavin yield can be increased by 22.8% compared with that of the high riboflavin-producing strain RF1.

公开(公告)号：US20180245114A1

公开(公告)日：2018-08-30

申请号：US15736489

申请日：2015-11-23

Applicant: Jiangnan University

Inventor： Zhiming RAO ,  Junxian ZHENG ,  Meijuan XU ,  Taowei YANG ,  Xian ZHANG

IPC: C12P13/14 ,  C12N15/62 ,  C12N15/77 ,  C12N9/88 ,  C12N9/24

CPC classification number: C12P13/14 ,  C07K2319/02 ,  C12N9/2491 ,  C12N9/88 ,  C12N15/62 ,  C12N15/77 ,  C12P13/005 ,  C12R1/13 ,  C12Y302/01025 ,  C12Y401/01015

Abstract: The present invention relates to application of a novel signal peptide in L-glutamate and its derivatives production from konjac powder, which belongs to the field of gene engineering, enzyme engineering and metabolism engineering. The signal peptide which mediated secretion of β-mannanase was invented, and the recombinant strain with this signal peptide had advantages on utilizing konjac powder to produce related products, and its utilization efficiency of konjac powder, production efficiency, and yield were higher than other signal peptides. The recombinant strain possessing this new signal peptide had advantages on utilizing cheaper konjac powder as substrate to lower the process costs on L-glutamic acid and its high-value-added products.

公开(公告)号：US20240344038A1

公开(公告)日：2024-10-17

申请号：US18415827

申请日：2024-01-18

Applicant: JIANGNAN UNIVERSITY

Inventor： Meijuan XU ,  Zhiming RAO ,  Yaxin LIAO ,  Haofei XU ,  Xian ZHANG ,  Taowei YANG

IPC: C12N9/10 ,  C12N15/70 ,  C12P13/04

CPC classification number: C12N9/1003 ,  C12N15/70 ,  C12P13/04 ,  C12Y201/04001

Abstract: The present invention discloses an L-arginine-glycine amidinotransferase and use thereof in the production of guanidinoacetic acid. In the present invention, through combined multi-site amino acid mutation, a technical effect of significantly improved enzyme activity of the mutant AkAGATT225Q/A258P/L278K than that of the wild-type strain is achieved, providing an application value for large-scale production of guanidinoacetic acid in industry. When the L-arginine-glycine amidinotransferase mutant constructed in the present invention is used in the production of guanidinoacetic acid, by optimizing the conversion conditions, the yield of guanidinoacetic acid is up to 21.4 g/L and the conversion rate is 90.4%, after 24 hrs of reaction in a 1 L reaction system. Compared with the production of guanidinoacetic acid with the raw enzyme, the yield is increased by 49.6%.

公开(公告)号：US20210087539A1

公开(公告)日：2021-03-25

申请号：US17094982

申请日：2020-11-11

Applicant: Jiangnan University

Inventor： Zhiming RAO ,  Minglong SHAO ,  Yetong WANG ,  Yuling WU ,  Taowei YANG ,  Xian ZHANG ,  Meijuan XU

IPC: C12N9/04 ,  C12P33/02 ,  C12N15/70

Abstract: The disclosure discloses 17β-hydroxysteroid dehydrogenase mutants and application thereof, and belongs to the technical field of biology. The disclosure provides 17β-hydroxysteroid dehydrogenase mutants V107A, T155N, H164Y and V107A/T155N/H164Y with high specific enzyme activities, and the specific enzyme activities of the 17β-hydroxysteroid dehydrogenase mutants V107A, T155N, H164Y and V107A/T155N/H164Y are as high as 1.85, 1.93, 2.06 and 5.15 U/mg, respectively, which are 1.11, 1.16, 1.24 and 3.10 times larger than that of wild-type 17β-hydroxysteroid dehydrogenase (1.66 U/mg).

公开(公告)号：US20180258385A1

公开(公告)日：2018-09-13

申请号：US15736544

申请日：2015-11-23

Applicant: Jiangnan University

Inventor： Zhiming RAO ,  Zhenghong XU ,  Junxian ZHENG ,  Meijuan XU ,  Taowei YANG ,  Xian ZHANG

IPC: C12N1/20 ,  C12N15/52 ,  C12P13/10 ,  C12N9/24

CPC classification number: C12N1/20 ,  C07K14/32 ,  C07K14/34 ,  C12N9/2491 ,  C12N15/52 ,  C12P13/10 ,  C12Y302/01025

Abstract: The present invention relates to application of a novel signal peptide in L-arginine and its derivatives production from konjac powder, which belongs to the field of gene engineering, enzyme engineering and metabolism engineering. The present invention fused the signal peptide set forth in SEQ ID NO.1 with the β-mannanase of Bacillus subtilis CCTCC M 209200, and expressed the fused gene in the strain with high L-arginine yield. The recombinant strain Corynebacterium crenatum CGMCC 0890/p MSPman had advantages on utilizing cheaper konjac powder as substrate, and after fermenting for 96 hours in a 5 L bioreactor, the L-arginine yield reached 45 g/L. Another two recombinant strains were constructed based on Corynebacterium crenatum CGMCC 0890/pMSPman, and after fermenting for 96 hours in a 5 L bioreactor, the L-ornithine yield and L-citrulline reached 23.5 g/L and 26.3 g/L respectively.

公开(公告)号：US20240018557A1

公开(公告)日：2024-01-18

申请号：US17930223

申请日：2022-09-07

Applicant: Jiangnan University

Inventor： Zhiming RAO ,  Zhenqiang ZHAO ,  Meijuan XU ,  Xian ZHANG ,  Taowei YANG

IPC: C12P13/08 ,  C12N15/70

CPC classification number: C12P13/08 ,  C12N15/70 ,  C12Y604/01001 ,  C12Y401/01032 ,  C12N2800/22

Abstract: The present disclosure provides a recombinant nucleic acid of Escherichia coli, a recombinant E. coli, a culturing method thereof, and a method for biosynthesizing L-threonine thereby, and relates to the technical field of bioengineering. The recombinant nucleic acid of E. coli of the present disclosure, including the gene encoding phosphoenolpyruvate carboxykinase (pck), the gene encoding pyruvate carboxylase (pyc) and the gene encoding threonine operon, is transformed into E. coli to obtain a recombinant E. coli LMT4 strain that takes glucose as a substrate. Using the LMT4 for fermentative production may significantly improve the L-threonine yield and glucose conversion rate, laying a foundation for the industrial production of L-threonine.

公开(公告)号：US20200149077A1

公开(公告)日：2020-05-14

申请号：US16682486

申请日：2019-11-13

Applicant: JIANGNAN UNIVERSITY

Inventor： Zhiming RAO ,  Song LIU ,  Renjie GAO ,  Xian ZHANG ,  Taowei YANG ,  Meijuan XU

IPC: C12P13/00 ,  C12N9/14 ,  C12N9/04 ,  C12N9/10 ,  C12N9/06

Abstract: The present invention discloses a method for producing a 1,2-amino alcohol compound by utilizing whole-cell transformation, and belongs to the technical field of gene engineering and microorganism engineering. According to the present invention, engineered Escherichia coli co-expresses epoxide hydrolase, alcohol dehydrogenase, ω-transaminase and glutamate dehydrogenase, is capable of realizing whole-cell catalysis of an epoxide in one step to synthesize a 1,2-amino alcohol compound, and meanwhile, can realize regeneration of coenzyme NADP+ and an amino doner L-Glu; alcohol dehydrogenase expressed by the engineered Escherichia coli is RBS optimized alcohol dehydrogenase, and such RBS optimization can control the expression quantity of alcohol dehydrogenase, so that the catalysis rate of alcohol dehydrogenase and transaminase can achieve an optimum ratio, to eliminate influence caused by a rate-limiting step in a catalyzing course.