1
|
Ma X, Zou D, Ji A, Jiang C, Zhao Z, Ding X, Han Z, Bao P, Chen K, Ma A, Wei X. Identification of a Novel Chitinase from Bacillus paralicheniformis: Gene Mining, Sequence Analysis, and Enzymatic Characterization. Foods 2024; 13:1777. [PMID: 38891005 PMCID: PMC11171888 DOI: 10.3390/foods13111777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Revised: 05/27/2024] [Accepted: 06/04/2024] [Indexed: 06/20/2024] Open
Abstract
In this study, a novel strain for degrading chitin was identified as Bacillus paralicheniformis HL37, and the key chitinase CH1 was firstly mined through recombinant expression in Bacillus amyloliquefaciens HZ12. Subsequently, the sequence composition and catalytic mechanism of CH1 protein were analyzed. The molecular docking indicated that the triplet of Asp526, Asp528, and Glu530 was a catalytic active center. The enzymatic properties analysis revealed that the optimal reaction temperature and pH was 65 °C and 6.0, respectively. Especially, the chitinase activity showed no significant change below 55 °C and it could maintain over 60% activity after exposure to 85 °C for 30 min. Moreover, the optimal host strain and signal peptide were obtained to enhance the expression of chitinase CH1 significantly. As far as we know, it was the first time finding the highly efficient chitin-degrading enzymes in B. paralicheniformis, and detailed explanations were provided on the catalytic mechanism and enzymatic properties on CH1.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Xuetuan Wei
- State Key Laboratory of Agricultural Microbiology, College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (X.M.); (D.Z.); (A.J.); (C.J.); (Z.Z.); (X.D.); (Z.H.); (P.B.); (K.C.); (A.M.)
| |
Collapse
|
2
|
Das S, Chowdhury C, Kumar SP, Roy D, Gosavi SW, Sen R. Microbial production of N-acetyl-D-glucosamine (GlcNAc) for versatile applications: Biotechnological strategies for green process development. Carbohydr Res 2024; 536:109039. [PMID: 38277719 DOI: 10.1016/j.carres.2024.109039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 12/07/2023] [Accepted: 01/09/2024] [Indexed: 01/28/2024]
Abstract
N-acetyl-d-glucosamine (GlcNAc) is a commercially important amino sugar for its wide range of applications in pharmaceutical, food, cosmetics and biofuel industries. In nature, GlcNAc is polymerised into chitin biopolymer, which is one of the major constituents of fungal cell wall and outer shells of crustaceans. Sea food processing industries generate a large volume of chitin as biopolymeric waste. Because of its high abundance, chitinaceous shellfish wastes have been exploited as one of the major precursor substrates of GlcNAc production, both in chemical and enzymatic means. Nevertheless, the current process of GlcNAc extraction from shellfish wastes generates poor turnover and attracts environmental hazards. Moreover, GlcNAc isolated from shellfish could not be prescribed to certain groups of people because of the allergic nature of shell components. Therefore, an alternative route of GlcNAc production is advocated. With the advancement of metabolic construction and synthetic biology, microbial synthesis of GlcNAc is gaining much attention nowadays. Several new and cutting-edge technologies like substrate co-utilization strategy, promoter engineering, and CRISPR interference system were proposed in this fascinating area. The study would put forward the potential application of microbial engineering in the production of important pharmaceuticals. Very recently, autotrophic fermentation of GlcNAc synthesis has been proposed. The metabolic engineering approaches would offer great promise to mitigate the issues of low yield and high production cost, which are major challenges in microbial bio-processes industries. Further process optimization, optimising metabolic flux, and efficient recovery of GlcNAc from culture broth, should be investigated in order to achieve a high product titer. The current study presents a comprehensive review on microbe-based eco-friendly green methods that would pave the way towards the development of future research directions in this field for the designing of a cost-effective fermentation process on an industrial setup.
Collapse
Affiliation(s)
- Sancharini Das
- Department of Environmental Science, Savitribai Phule Pune University, Pune, MH, 411007, India; Department of Biotechnology, Indian Institute of Technology Kharagpur, WB, 721302, India.
| | - Chiranjit Chowdhury
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, MH, 411008, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, UP, 201002, India
| | - S Pavan Kumar
- Department of Biotechnology, Indian Institute of Technology Madras, Chennai, TN, 600 036, India
| | - Debasis Roy
- Department of Civil Engineering, Indian Institute of Technology Kharagpur, WB, 721302, India
| | - Suresh W Gosavi
- Department of Environmental Science, Savitribai Phule Pune University, Pune, MH, 411007, India
| | - Ramkrishna Sen
- Department of Biotechnology, Indian Institute of Technology Kharagpur, WB, 721302, India
| |
Collapse
|
3
|
Gupta A, Kang K, Pathania R, Saxton L, Saucedo B, Malik A, Torres-Tiji Y, Diaz CJ, Dutra Molino JV, Mayfield SP. Harnessing genetic engineering to drive economic bioproduct production in algae. Front Bioeng Biotechnol 2024; 12:1350722. [PMID: 38347913 PMCID: PMC10859422 DOI: 10.3389/fbioe.2024.1350722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 01/16/2024] [Indexed: 02/15/2024] Open
Abstract
Our reliance on agriculture for sustenance, healthcare, and resources has been essential since the dawn of civilization. However, traditional agricultural practices are no longer adequate to meet the demands of a burgeoning population amidst climate-driven agricultural challenges. Microalgae emerge as a beacon of hope, offering a sustainable and renewable source of food, animal feed, and energy. Their rapid growth rates, adaptability to non-arable land and non-potable water, and diverse bioproduct range, encompassing biofuels and nutraceuticals, position them as a cornerstone of future resource management. Furthermore, microalgae's ability to capture carbon aligns with environmental conservation goals. While microalgae offers significant benefits, obstacles in cost-effective biomass production persist, which curtails broader application. This review examines microalgae compared to other host platforms, highlighting current innovative approaches aimed at overcoming existing barriers. These approaches include a range of techniques, from gene editing, synthetic promoters, and mutagenesis to selective breeding and metabolic engineering through transcription factors.
Collapse
Affiliation(s)
- Abhishek Gupta
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Kalisa Kang
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Ruchi Pathania
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Lisa Saxton
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Barbara Saucedo
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Ashleyn Malik
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Yasin Torres-Tiji
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Crisandra J. Diaz
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - João Vitor Dutra Molino
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Stephen P. Mayfield
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
- California Center for Algae Biotechnology, University of California San Diego, San Diego, CA, United States
| |
Collapse
|
4
|
Nie M, Wang J, Zhang K. Engineering a Novel Acetyl-CoA Pathway for Efficient Biosynthesis of Acetyl-CoA-Derived Compounds. ACS Synth Biol 2024; 13:358-369. [PMID: 38151239 DOI: 10.1021/acssynbio.3c00613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Acetyl-CoA is an essential central metabolite in living organisms and a key precursor for various value-added products as well. However, the intracellular availability of acetyl-CoA limits the efficient production of these target products due to complex and strict regulation. Here, we proposed a new acetyl-CoA pathway, relying on two enzymes, threonine aldolase and acetaldehyde dehydrogenase (acetylating), which can convert one l-threonine into one acetyl-CoA, one glycine, and generate one NADH, without carbon loss. Introducing the acetyl-CoA pathway could increase the intracellular concentration of acetyl-CoA by 8.6-fold compared with the wild-type strain. To develop a cost-competitive and genetically stable acetyl-CoA platform strain, the new acetyl-CoA pathway, driven by the constitutive strong promoter, was integrated into the chromosome of Escherichia coli. We demonstrated the practical application of this new acetyl-CoA pathway by high titer production of β-alanine, mevalonate, and N-acetylglucosamine. At the same time, this pathway achieved a high-yield production of glycine, a value-added commodity chemical for the synthesis of glyphosate and thiamphenicol. This work shows the potential of this new acetyl-CoA pathway for the industrial production of acetyl-CoA-derived compounds.
Collapse
Affiliation(s)
- Mengzhen Nie
- Zhejiang University, Hangzhou, Zhejiang 310027, China
- Center of Synthetic Biology and Integrated Bioengineering, School of Engineering, Westlake University, Hangzhou, Zhejiang 310030, China
| | - Jingyu Wang
- Center of Synthetic Biology and Integrated Bioengineering, School of Engineering, Westlake University, Hangzhou, Zhejiang 310030, China
| | - Kechun Zhang
- Center of Synthetic Biology and Integrated Bioengineering, School of Engineering, Westlake University, Hangzhou, Zhejiang 310030, China
| |
Collapse
|
5
|
Peng Y, Xu P, Tao F. Production of N-acetylglucosamine with Vibrio alginolyticus FA2, an emerging platform for economical unsterile open fermentation. Synth Syst Biotechnol 2023; 8:546-554. [PMID: 37637200 PMCID: PMC10457514 DOI: 10.1016/j.synbio.2023.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/01/2023] [Accepted: 08/09/2023] [Indexed: 08/29/2023] Open
Abstract
Members of the Vibrionaceae family are predominantly fast-growing and halophilic microorganisms that have captured the attention of researchers owing to their potential applications in rapid biotechnology. Among them, Vibrio alginolyticus FA2 is a particularly noteworthy halophilic bacterium that exhibits superior growth capability. It has the potential to serve as a biotechnological platform for sustainable and eco-friendly open fermentation with seawater. To evaluate this hypothesis, we integrated the N-acetylglucosamine (GlcNAc) pathway into V. alginolyticus FA2. Seven nag genes were knocked out to obstruct the utilization of GlcNAc, and then 16 exogenous gna1s co-expressing with EcglmS were introduced to strengthen the flux of GlcNAc pathway, respectively. To further enhance GlcNAc production, we fine-tuned promoter strength of the two genes and inactivated two genes alsS and alsD to prevent the production of acetoin. Furthermore, unsterile open fermentation was carried out using simulated seawater and a chemically defined medium, resulting in the production of 9.2 g/L GlcNAc in 14 h. This is the first report for de-novo synthesizing GlcNAc with a Vibrio strain, facilitated by an unsterile open fermentation process employing seawater as a substitute for fresh water. This development establishes a basis for production of diverse valuable chemicals using Vibrio strains and provides insights into biomanufacture.
Collapse
Affiliation(s)
- Yuan Peng
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Ping Xu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Fei Tao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| |
Collapse
|
6
|
Liu L, Li G, Cao H. The Multiomics Response of Bacillus subtilis to Simultaneous Genetic and Environmental Perturbations. Microorganisms 2023; 11:1949. [PMID: 37630509 PMCID: PMC10458161 DOI: 10.3390/microorganisms11081949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 07/16/2023] [Accepted: 07/27/2023] [Indexed: 08/27/2023] Open
Abstract
How bacteria respond at the systems level to both genetic and environmental perturbations imposed at the same time is one fundamental yet open question in biology. Bioengineering or synthetic biology provides an ideal system for studying such responses, as engineered strains always have genetic changes as opposed to wildtypes and are grown in conditions which often change during growth for maximal yield of desired products. So, engineered strains were used to address the outstanding question. Two Bacillus subtilis strains (MT1 and MT2) were created previously for the overproduction of N-acetylglucosamine (GlcNAc), which were grown in an environment with a carbon shift from glucose to glucose and xylose in the same culture system. We had four groups: (1) a wildtype (WT) grown with glucose at t1; (2) a WT with glucose and xylose at t2; (3) a mutant (MT1) grown with glucose at t1; and (4) MT1 with glucose and xylose at t2. By measuring transcriptomes and metabolomes, we found that GlcNAc-producing mutants, particularly MT2, had a higher yield of N-acetylglucosamine than WT but displayed a smaller maximum growth rate than the wildtype, despite MT1 reaching higher carrying capacity. Underlying the observed growth, the engineered pathways leading to N-acetylglucosamine had both higher gene expression and associated metabolite concentrations in MT1 than WT at both t1 and t2; in bioenergetics, there was higher energy supply in terms of ATP and GTP, with the energy state metric higher in MT1 than WT at both timepoints. Additionally, most top key precursor metabolites were equally abundant in MT1 and WT at either timepoints. Besides that, one prominent feature was the high consistency between transcriptomics and metabolomics in revealing the response. First, both metabolomes and transcriptomes revealed the same PCA clusters of the four groups. Second, we found that the important functions enriched both by metabolomes and transcriptomes overlapped, such as amino acid metabolism and ABC transport. Strikingly, these functions overlapped those enriched by the genes showing a high (positive or negative) correlation with metabolites. Furthermore, these functions also overlapped the enriched KEGG pathways identified using weighted gene coexpression network analysis. All these findings suggest that the responses to simultaneous genetic and environmental perturbations are well coordinated at the metabolic and transcriptional levels: they rely heavily on bioenergetics, but core metabolism does not differ much, while amino acid metabolism and ABC transport are important. This serves as a design guide for bioengineering, synthetic biology, and systems biology.
Collapse
Affiliation(s)
| | | | - Huansheng Cao
- Division of Natural and Applied Sciences, Duke Kunshan University, Suzhou 215316, China; (L.L.); (G.L.)
| |
Collapse
|
7
|
Wang X, Chang F, Wang T, Luo H, Su X, Tu T, Wang Y, Bai Y, Qin X, Zhang H, Wang Y, Yao B, Huang H, Zhang J. Production of N-acetylglucosamine from carbon dioxide by engineering Cupriavidus necator H16. BIORESOURCE TECHNOLOGY 2023; 379:129024. [PMID: 37028529 DOI: 10.1016/j.biortech.2023.129024] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 04/01/2023] [Accepted: 04/03/2023] [Indexed: 05/03/2023]
Abstract
The conversion of CO2 into valuable bioactive substances using synthetic biological techniques is a potential approach for mitigating the greenhouse effect. Here, the engineering of C. necator H16 to produce N-acetylglucosamine (GlcNAc) from CO2 is reported. First, GlcNAc importation and intracellular metabolic pathways were disrupted by the deletion of nagF, nagE, nagC, nagA and nagB genes. Second, the GlcNAc-6-phosphate N-acetyltransferase gene (gna1) was screened. A GlcNAc-producing strain was constructed by overexpressing a mutant gna1 from Caenorhabditis elegans. A further increase in GlcNAc production was achieved by disrupting poly(3-hydroxybutyrate) biosynthesis and the Entner-Doudoroff pathways. The maximum GlcNAc titers were 199.9 and 566.3 mg/L for fructose and glycerol, respectively. Finally, the best strain achieved a GlcNAc titer of 75.3 mg/L in autotrophic fermentation. This study demonstrated a conversion of CO2 to GlcNAc, thereby providing a feasible approach for the biosynthesis of various bioactive chemicals from CO2 under normal conditions..
Collapse
Affiliation(s)
- Xiaolu Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fangfang Chang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Tingting Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huiying Luo
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Xiaoyun Su
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Tao Tu
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yuan Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yingguo Bai
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Xing Qin
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Honglian Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yaru Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Bin Yao
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huoqing Huang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Jie Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| |
Collapse
|
8
|
Liu Y, Cheng H, Li H, Zhang Y, Wang M. A Programmable CRISPR/Cas9 Toolkit Improves Lycopene Production in Bacillus subtilis. Appl Environ Microbiol 2023; 89:e0023023. [PMID: 37272803 PMCID: PMC10305015 DOI: 10.1128/aem.00230-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/16/2023] [Indexed: 06/06/2023] Open
Abstract
Bacillus subtilis has been widely used and generally recognized as a safe host for the production of recombinant proteins, high-value chemicals, and pharmaceuticals. Thus, its metabolic engineering attracts significant attention. Nevertheless, the limited availability of selective markers makes this process difficult and time-consuming, especially in the case of multistep biosynthetic pathways. Here, we employ CRISPR/Cas9 technology to build an easy cloning toolkit that addresses commonly encountered obstacles in the metabolic engineering of B. subtilis, including the chromosomal integration locus, promoter, terminator, and guide RNA (gRNA) target. Six promoters were characterized, and the promoter strengths ranged from 0.9- to 23-fold that of the commonly used strong promoter P43. We characterized seven terminators in B. subtilis, and the termination efficiencies (TEs) of the seven terminators are all more than 90%. Six gRNA targets were designed upstream of the promoter and downstream of the terminator. Using a green fluorescent protein (GFP) reporter, we confirmed integration efficiency with the single-locus integration site is up to 100%. We demonstrated the applicability of this toolkit by optimizing the expression of a challenging but industrially important product, lycopene. By heterologous expression of the essential genes for lycopene synthesis on the B. subtilis genome, a total of 13 key genes involved in the lycopene biosynthetic pathway were manipulated. Moreover, our findings showed that the gene cluster ispG-idi-dxs-ispD could positively affect the production of lycopene, while the cluster dxr-ispE-ispF-ispH had a negative effect on lycopene production. Hence, our multilocus integration strategy can facilitate the pathway assembly for production of complex chemicals and pharmaceuticals in B. subtilis. IMPORTANCE We present a toolkit that allows for rapid cloning procedures and one-step subcloning to move from plasmid-based expression to stable chromosome integration and expression in a production strain in less than a week. The utility of the customized tool was demonstrated by integrating the MEP (2C-methyl-d-erythritol-4-phosphate) pathway, part of the pentose phosphate pathway (PPP), and the hetero-lycopene biosynthesis genes by stable expression in the genome. The tool could be useful to engineer B. subtilis strains through diverse recombination events and ultimately improve its potential and scope of industrial application as biological chassis.
Collapse
Affiliation(s)
- Yang Liu
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Haijiao Cheng
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Haoni Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Yingzhe Zhang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Meng Wang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| |
Collapse
|
9
|
An update on the review of microbial synthesis of glucosamine and N-acetylglucosamine. World J Microbiol Biotechnol 2023; 39:93. [PMID: 36754899 DOI: 10.1007/s11274-023-03531-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/19/2023] [Indexed: 02/10/2023]
Abstract
Glucosamine (GlcN) is a natural amino monosaccharide in which a hydroxyl group of glucose is substituted by an amino group. It belongs to functional amino sugar compounds. In the traditional preparation process, GlcN and GlcNAc are obtained by hydrolyzing the cell wall of shrimp and crab. There are many potential problems with this method, such as geographical and seasonal restrictions on the supply of raw materials, serious environmental pollution and potential allergic reactions. Microbial fermentation has the advantages of mild conditions, low environmental pollution, high production intensity, and product safety. It can effectively solve the problem of shrimp and crab hydrolysis process, attracting many researchers to participate in the research of microbial fermentation production of GlcN. This paper mainly summarizes the research on strain construction method, metabolic pathway design and fermentation condition optimization in microbial fermentation, which has certain guiding significance for the further production, research and production of glucosamine.
Collapse
|
10
|
Soni T, Zhuang M, Kumar M, Balan V, Ubanwa B, Vivekanand V, Pareek N. Multifaceted production strategies and applications of glucosamine: a comprehensive review. Crit Rev Biotechnol 2023; 43:100-120. [PMID: 34923890 DOI: 10.1080/07388551.2021.2003750] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Glucosamine (GlcN) and its derivatives are in high demand and used in various applications such as food, a precursor for the biochemical synthesis of fuels and chemicals, drug delivery, cosmetics, and supplements. The vast number of applications attributed to GlcN has raised its demand, and there is a growing emphasis on developing production methods that are sustainable and economical. Several: physical, chemical, enzymatic, microbial fermentation, recombinant processing methods, and their combinations have been reported to produce GlcN from chitin and chitosan available from different sources, such as animals, plants, and fungi. In addition, genetic manipulation of certain organisms has significantly improved the quality and yield of GlcN compared to conventional processing methods. This review will summarize the chitin and chitosan-degrading enzymes found in various organisms and the expression systems that are widely used to produce GlcN. Furthermore, new developments and methods, including genetic and metabolic engineering of Escherichia coli and Bacillus subtilis to produce high titers of GlcN and GlcNAc will be reviewed. Moreover, other sources of glucosamine production viz. starch and inorganic ammonia will also be discussed. Finally, the conversion of GlcN to fuels and chemicals using catalytic and biochemical conversion will be discussed.
Collapse
Affiliation(s)
- Twinkle Soni
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Mengchuan Zhuang
- Department of Engineering Technology, College of Technology, University of Houston, Sugar Land, TX, USA
| | - Manish Kumar
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Venkatesh Balan
- Department of Engineering Technology, College of Technology, University of Houston, Sugar Land, TX, USA
| | - Bryan Ubanwa
- Department of Engineering Technology, College of Technology, University of Houston, Sugar Land, TX, USA
| | - Vivekanand Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology, Jaipur, India
| | - Nidhi Pareek
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| |
Collapse
|
11
|
Sun G, Wu Y, Huang Z, Liu Y, Li J, Du G, Lv X, Liu L. Directed evolution of diacetylchitobiose deacetylase via high-throughput droplet sorting with a novel, bacteria-based biosensor. Biosens Bioelectron 2023; 219:114818. [PMID: 36327560 DOI: 10.1016/j.bios.2022.114818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/02/2022] [Accepted: 10/12/2022] [Indexed: 11/19/2022]
Abstract
Numerous biological disciplines rely on high-throughput cell sorting. Flow cytometry, the current gold standard, is capable of ultrahigh-throughput cell sorting, but measurements are primarily limited to cell size and surface marker. Droplet sorting technology is gaining increasing attention with the ability to provide an individual environment for the analysis of single-cell secretion. Although various droplet detecting methods, such as fluorescence, absorbance, mass spectrum, imaging analysis, have been developed for droplet sorting, it remains challenging to establish high-throughput sorting methods for numerous analytes. We aim to develop a high-throughput sorting system based on the glucosamine (GlcN) measurement for the directed evolution of diacetylchitobiose deacetylase (Dac), the key enzyme for GlcN production. To overcome the limitation that no high-throughput sorting system existed for GlcN, we designed a novel bacteria-based biosensor capable of converting GlcN to a positively correlated fluorescence signal. Through characterization and optimization, it was possible to detect GlcN in droplets for high-throughput droplet sorting. We recovered the best Dac mutant S60I/R157T/F168S after sorting ∼0.2 million Dac mutants; its activity was 48.6 ± 1.5 U/mL, which was 1.8-times that of our previously discovered Dac mutant R157T (27.2 ± 1.8 U/mL). This result successfully demonstrated the combination of high-throughput droplet sorting technology and a bacteria-based biosensor, which could facilitate the industrial production of GlcN and serve as a model for similar droplet sorting applications.
Collapse
Affiliation(s)
- Guoyun Sun
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Yaokang Wu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Ziyang Huang
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China.
| |
Collapse
|
12
|
Research Progress on the Effect of Autolysis to Bacillus subtilis Fermentation Bioprocess. FERMENTATION 2022. [DOI: 10.3390/fermentation8120685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Bacillus subtilis is a gram-positive bacterium, a promising microorganism due to its strong extracellular protein secretion ability, non-toxic, and relatively mature industrial fermentation technology. However, cell autolysis during fermentation restricts the industrial application of B. subtilis. With the fast advancement of molecular biology and genetic engineering technology, various advanced procedures and gene editing tools have been used to successfully construct autolysis-resistant B. subtilis chassis cells to manufacture various biological products. This paper first analyses the causes of autolysis in B. subtilis from a mechanistic perspective and outlines various strategies to address autolysis in B. subtilis. Finally, potential strategies for solving the autolysis problem of B. subtilis are foreseen.
Collapse
|
13
|
Deng C, Zhao M, Zhao Q, Zhao L. Advances in green bioproduction of marine and glycosaminoglycan oligosaccharides. Carbohydr Polym 2022; 300:120254. [DOI: 10.1016/j.carbpol.2022.120254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 11/02/2022]
|
14
|
Design of 5′-UTR to Enhance Keratinase Activity in Bacillus subtilis. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8090426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Keratinase is an important industrial enzyme, but its application performance is limited by its low activity. A rational design of 5′-UTRs that increases translation efficiency is an important approach to enhance protein expression. Herein, we optimized the 5′-UTR of the recombinant keratinase KerZ1 expression element to enhance its secretory activity in Bacillus subtilis WB600 through Spacer design, RBS screening, and sequence simplification. First, the A/U content in Spacer was increased by the site-directed saturation mutation of G/C bases, and the activity of keratinase secreted by mutant strain B. subtilis WB600-SP was 7.94 times higher than that of KerZ1. Subsequently, the keratinase activity secreted by the mutant strain B. subtilis WB600-SP-R was further increased to 13.45 times that of KerZ1 based on the prediction of RBS translation efficiency and the multi-site saturation mutation screening. Finally, the keratinase activity secreted by the mutant strain B. subtilis WB600-SP-R-D reached 204.44 KU mL−1 by reducing the length of the 5′ end of the 5′-UTR, which was 19.70 times that of KerZ1. In a 5 L fermenter, the keratinase activity secreted by B. subtilis WB600-SP-R-D after 25 h fermentation was 797.05 KU mL−1, which indicated its high production intensity. Overall, the strategy of this study and the obtained keratinase mutants will provide a good reference for the expression regulation of keratinase and other industrial enzymes.
Collapse
|
15
|
A Two-Step Cross-Linked Hydrogel Immobilization Strategy for Diacetylchitobiose Deacetylase. Catalysts 2022. [DOI: 10.3390/catal12090932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Free enzymes often face economic problems due to their non-recyclability, which limits their applications for industrial manufacturing. Organic biopolymers are frequently used to fabricate hydrogel for enzyme immobilization due to their advantages of non-toxicity, biocompatibility, biodegradability, and flexibility. However, for highly thermostable enzymes, simple cross-linking causes either low immobilizing efficiency or low thermal stability. Herein, we developed a novel enzyme immobilization strategy with two-step cross-linked gelatin hydrogel for thermostable enzymes working at high temperature. The hydrogel was firstly “soft cross-linked” to immobilize most enzyme molecules and then “hard cross-linked” to gain strong thermal stability. We selected the enzyme diacetylchitobiose deacetylase (Dac), which was firstly derived from hyperthermophilic bacteria, to demonstrate the advantages of our method. With the optimized fabrication steps, our hydrogel showed ~87% Dac immobilization efficiency and excellent stability against heating, dehydrating, long-time storing, and massive recycling. Importantly, our hydrogel showed ~85.0% relative enzyme activity at 80 °C and retained ~65.8% activity after 10 rounds of catalysis. This strategy showed high immobilizing efficiency and strong thermal stability and we believe it could improve the industrial potential for those enzymes.
Collapse
|
16
|
Refactoring transcription factors for metabolic engineering. Biotechnol Adv 2022; 57:107935. [PMID: 35271945 DOI: 10.1016/j.biotechadv.2022.107935] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 02/04/2022] [Accepted: 03/03/2022] [Indexed: 12/19/2022]
Abstract
Due to the ability to regulate target metabolic pathways globally and dynamically, metabolic regulation systems composed of transcription factors have been widely used in metabolic engineering and synthetic biology. This review introduced the categories, action principles, prediction strategies, and related databases of transcription factors. Then, the application of global transcription machinery engineering technology and the transcription factor-based biosensors and quorum sensing systems are overviewed. In addition, strategies for optimizing the transcriptional regulatory tools' performance by refactoring transcription factors are summarized. Finally, the current limitations and prospects of constructing various regulatory tools based on transcription factors are discussed. This review will provide theoretical guidance for the rational design and construction of transcription factor-based metabolic regulation systems.
Collapse
|
17
|
Kroef V, Ruegenberg S, Horn M, Allmeroth K, Ebert L, Bozkus S, Miethe S, Elling U, Schermer B, Baumann U, Denzel MS. GFPT2/GFAT2 and AMDHD2 act in tandem to control the hexosamine pathway. eLife 2022; 11:69223. [PMID: 35229715 PMCID: PMC8970586 DOI: 10.7554/elife.69223] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 02/28/2022] [Indexed: 11/25/2022] Open
Abstract
The hexosamine biosynthetic pathway (HBP) produces the essential metabolite UDP-GlcNAc and plays a key role in metabolism, health, and aging. The HBP is controlled by its rate-limiting enzyme glutamine fructose-6-phosphate amidotransferase (GFPT/GFAT) that is directly inhibited by UDP-GlcNAc in a feedback loop. HBP regulation by GFPT is well studied but other HBP regulators have remained obscure. Elevated UDP-GlcNAc levels counteract the glycosylation toxin tunicamycin (TM), and thus we screened for TM resistance in haploid mouse embryonic stem cells (mESCs) using random chemical mutagenesis to determine alternative HBP regulation. We identified the N-acetylglucosamine deacetylase AMDHD2 that catalyzes a reverse reaction in the HBP and its loss strongly elevated UDP-GlcNAc. To better understand AMDHD2, we solved the crystal structure and found that loss-of-function (LOF) is caused by protein destabilization or interference with its catalytic activity. Finally, we show that mESCs express AMDHD2 together with GFPT2 instead of the more common paralog GFPT1. Compared with GFPT1, GFPT2 had a much lower sensitivity to UDP-GlcNAc inhibition, explaining how AMDHD2 LOF resulted in HBP activation. This HBP configuration in which AMDHD2 serves to balance GFPT2 activity was also observed in other mESCs and, consistently, the GFPT2:GFPT1 ratio decreased with differentiation of human embryonic stem cells. Taken together, our data reveal a critical function of AMDHD2 in limiting UDP-GlcNAc production in cells that use GFPT2 for metabolite entry into the HBP.
Collapse
Affiliation(s)
- Virginia Kroef
- Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Sabine Ruegenberg
- Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | | | - Kira Allmeroth
- Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | | | | | - Stephan Miethe
- Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Ulrich Elling
- Vienna Biocenter, Austrian Academy of Sciences, Vienna, Austria
| | | | | | | |
Collapse
|
18
|
Wang K, Wang X, Luo H, Wang Y, Wang Y, Tu T, Qin X, Bai Y, Huang H, Yao B, Su X, Zhang J. Synergetic Fermentation of Glucose and Glycerol for High-Yield N-Acetylglucosamine Production in Escherichia coli. Int J Mol Sci 2022; 23:ijms23020773. [PMID: 35054959 PMCID: PMC8775389 DOI: 10.3390/ijms23020773] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/28/2021] [Accepted: 01/09/2022] [Indexed: 01/13/2023] Open
Abstract
N-acetylglucosamine (GlcNAc) is an amino sugar that has been widely used in the nutraceutical and pharmaceutical industries. Recently, microbial production of GlcNAc has been developed. One major challenge for efficient biosynthesis of GlcNAc is to achieve appropriate carbon flux distribution between growth and production. Here, a synergistic substrate co-utilization strategy was used to address this challenge. Specifically, glycerol was utilized to support cell growth and generate glutamine and acetyl-CoA, which are amino and acetyl donors, respectively, for GlcNAc biosynthesis, while glucose was retained for GlcNAc production. Thanks to deletion of the 6-phosphofructokinase (PfkA and PfkB) and glucose-6-phosphate dehydrogenase (ZWF) genes, the main glucose catabolism pathways of Escherichia coli were blocked. The resultant mutant showed a severe defect in glucose consumption. Then, the GlcNAc production module containing glucosamine-6-phosphate synthase (GlmS*), glucosamine-6-phosphate N-acetyltransferase (GNA1*) and GlcNAc-6-phosphate phosphatase (YqaB) expression cassettes was introduced into the mutant, to drive the carbon flux from glucose to GlcNAc. Furthermore, co-utilization of glucose and glycerol was achieved by overexpression of glycerol kinase (GlpK) gene. Using the optimized fermentation medium, the final strain produced GlcNAc with a high stoichiometric yield of 0.64 mol/mol glucose. This study offers a promising strategy to address the challenge of distributing carbon flux in GlcNAc production.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Xiaoyun Su
- Correspondence: (X.S.); (J.Z.); Tel.: +86-10-62599910 (X.S. & J.Z.)
| | - Jie Zhang
- Correspondence: (X.S.); (J.Z.); Tel.: +86-10-62599910 (X.S. & J.Z.)
| |
Collapse
|
19
|
Huang Z, Mao X, Lv X, Sun G, Zhang H, Lu W, Liu Y, Li J, Du G, Liu L. Engineering diacetylchitobiose deacetylase from Pyrococcus horikoshii towards an efficient glucosamine production. BIORESOURCE TECHNOLOGY 2021; 334:125241. [PMID: 33964814 DOI: 10.1016/j.biortech.2021.125241] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/24/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
In this study, semi-rational design based on site-directed saturation mutagenesis and surface charge modification was used to improve the catalytic efficiency of the diacetylchitobiose deacetylase derived from Pyrococcus horikoshii (PhDac). PhDac mutant M14, which was screened by site-directed saturation mutagenesis, showed a ~ 2.21 -fold enhanced catalytic efficiency (kcat/Km) and the specific activity was improved by 70.02%. To keep the stability of glucosamine (GlcN), we reduced the optimal pH of M14 by modifying the surface charge from -35 to -59 to obtain mutant M20, whose specific activity reached 2 -fold of the wild-type. The conversion rate of N-acetylglucosamine (GlcNAc) to GlcN catalyzed by M20 reached 94.3%. Moreover, the decline of GlcN production was slowed down by the reduction of pH when temperature was higher than 50 ℃. Our results would accelerate the process of industrial production of GlcN by biocatalysis.
Collapse
Affiliation(s)
- Ziyang Huang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
| | - Xinzhu Mao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
| | - Guoyun Sun
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
| | - Hongzhi Zhang
- Shandong Runde Biotechnology Co., Ltd., Tai'an 271000, China
| | - Wei Lu
- Shandong Runde Biotechnology Co., Ltd., Tai'an 271000, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi 214122, China.
| |
Collapse
|
20
|
Deng C, Lv X, Li J, Zhang H, Liu Y, Du G, Amaro RL, Liu L. Synergistic improvement of N-acetylglucosamine production by engineering transcription factors and balancing redox cofactors. Metab Eng 2021; 67:330-346. [PMID: 34329707 DOI: 10.1016/j.ymben.2021.07.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/29/2021] [Accepted: 07/26/2021] [Indexed: 12/17/2022]
Abstract
The regulation of single gene transcription level in the metabolic pathway is often failed to significantly improve the titer of the target product, and even leads to the imbalance of carbon/nitrogen metabolic network and cofactor network. Global transcription machinery engineering (gTME) can activate or inhibit the synergistic expression of multiple genes in specific metabolic pathways, so transcription factors with specific functions can be expressed according to different metabolic regulation requirements, thus effectively increasing the synthesis of target metabolites. In addition, maintaining intracellular redox balance through cofactor engineering can realize the self-balance of cofactors and promote the efficient synthesis of target products. In this study, we rebalanced the central carbon/nitrogen metabolism and redox metabolism of Corynebacterium glutamicum S9114 by gTME and redox cofactors engineering to promote the production of the nutraceutical N-acetylglucosamine (GlcNAc). Firstly, it was found that the overexpression of the transcription factor RamA can promote GlcNAc synthesis, and the titer was further improved to 16 g/L in shake flask by using a mutant RamA (RamAM). Secondly, a CRISPR interference (CRISPRi) system based on dCpf1 was developed and used to inhibit the expression of global negative transcriptional regulators of GlcNAc synthesis, which promoted the GlcNAc titer to 27.5 g/L. Thirdly, the cofactor specificity of the key enzymes in GlcNAc synthesis pathway was changed by rational protein engineering, and the titer of GlcNAc in shake flask was increased to 36.9 g/L. Finally, the production of GlcNAc was scaled up in a 50-L fermentor, and the titer reached 117.1 ± 1.9 g/L, which was 6.62 times that of the control group (17.7 ± 0.4 g/L), and the yield was increased from 0.19 g/g to 0.31 g/g glucose. The results obtained here highlight the importance of engineering the global regulation of central carbon/nitrogen metabolism and redox metabolism to improve the production performance of microbial cell factories.
Collapse
Affiliation(s)
- Chen Deng
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Science Center for Future Foods, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Hongzhi Zhang
- Shandong Runde Biotechnology Co, Ltd, Tai'an, 271000, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Rodrigo Ledesma Amaro
- Department of Bioengineering and Imperial College Centre for Synthetic Biology, Imperial College London, London, SW72AZ, UK
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Ministry of Education, Jiangnan University, Wuxi, 214122, China.
| |
Collapse
|
21
|
Mavrommati M, Daskalaki A, Papanikolaou S, Aggelis G. Adaptive laboratory evolution principles and applications in industrial biotechnology. Biotechnol Adv 2021; 54:107795. [PMID: 34246744 DOI: 10.1016/j.biotechadv.2021.107795] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 06/11/2021] [Accepted: 07/05/2021] [Indexed: 12/20/2022]
Abstract
Adaptive laboratory evolution (ALE) is an innovative approach for the generation of evolved microbial strains with desired characteristics, by implementing the rules of natural selection as presented in the Darwinian Theory, on the laboratory bench. New as it might be, it has already been used by several researchers for the amelioration of a variety of characteristics of widely used microorganisms in biotechnology. ALE is used as a tool for the deeper understanding of the genetic and/or metabolic pathways of evolution. Another important field targeted by ALE is the manufacturing of products of (high) added value, such as ethanol, butanol and lipids. In the current review, we discuss the basic principles and techniques of ALE, and then we focus on studies where it has been applied to bacteria, fungi and microalgae, aiming to improve their performance to biotechnological procedures and/or inspect the genetic background of evolution. We conclude that ALE is a promising and efficacious method that has already led to the acquisition of useful new microbiological strains in biotechnology and could possibly offer even more interesting results in the future.
Collapse
Affiliation(s)
- Maria Mavrommati
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece; Laboratory of Food Microbiology and Biotechnology, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece
| | - Alexandra Daskalaki
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece
| | - Seraphim Papanikolaou
- Laboratory of Food Microbiology and Biotechnology, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece
| | - George Aggelis
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece.
| |
Collapse
|
22
|
Peng Z, Zhang J, Song Y, Guo R, Du G, Chen J. Engineered pro-peptide enhances the catalytic activity of keratinase to improve the conversion ability of feather waste. Biotechnol Bioeng 2021; 118:2559-2571. [PMID: 33788275 DOI: 10.1002/bit.27771] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/22/2021] [Accepted: 03/28/2021] [Indexed: 01/28/2023]
Abstract
Keratinase is an attractive industrial enzyme that can specifically catalyze keratin waste to obtain value-added products. A challenge to the application of keratinase is improving catalytic capacity to achieve efficient hydrolysis. In this study, we effectively expressed the keratinase gene from Bacillus licheniformis BBE11-1 in Bacillus subtilis WB600 based on pro-peptide engineering. Partial deletion of the pro-peptide sequence and the substitution of amino acid at the pro-peptide cleavage site (P1) suggested that the "chaperone effect" and "cleavage efficiency" of the pro-peptide determine the activity of the mature enzyme. Subsequently, seven target sites that can increase the activity of the mature enzyme by 16%-66% were obtained through the multiple sequence alignment of pro-peptides and site-directed mutation. We further performed combinatorial mutations at six sites based on the design principle of three-codon saturation mutations and obtained mutant 2-D12 (236.8 KU/mg) with a mature enzyme activity of 186% of the original (127.6 KU/mg). Finally, continuous fermentation was carried out in a 5-L bioreactor for 22 h, and the activity of the 2-D12 mature enzyme was increased to 391.6 KU/mg. Most importantly, 2-D12 could degrade more than 90% of feather waste into amino acids and peptides within 12 h with the aid of sulfite.
Collapse
Affiliation(s)
- Zheng Peng
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,School of Biotechnology, Jiangnan University, Wuxi, China
| | - Juan Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,School of Biotechnology, Jiangnan University, Wuxi, China
| | - Yang Song
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,School of Biotechnology, Jiangnan University, Wuxi, China
| | - Rong Guo
- Wuhan Institute of Industrial Control Technology Co., Ltd., Wuhan, China
| | - Guocheng Du
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jian Chen
- School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China
| |
Collapse
|
23
|
Zhu Y, Wan L, Meng J, Luo G, Chen G, Wu H, Zhang W, Mu W. Metabolic Engineering of Escherichia coli for Lacto- N-triose II Production with High Productivity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:3702-3711. [PMID: 33755468 DOI: 10.1021/acs.jafc.1c00246] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Lacto-N-triose II (LNT II), a core structural unit of human milk oligosaccharides (HMOs), has attracted substantial attention for its nutraceutical potentials and applications in the production of complex HMOs. In this study, Escherichia coli was metabolically engineered to efficiently produce LNT II using glycerol as a carbon source and lactose as a substrate. The UDP-N-acetylglucosamine (UDP-GlcNAc) biosynthesis pathway was strengthened, and β-1,3-N-acetylglucosaminyltransferase (LgtA) was introduced to construct an LNT II-producing base strain. To increase the titer and yield of LNT II, combinatorial optimization of the copy number and the ribosomal binding site sequence was performed to tune the gene expression strength and translation rates of the pathway enzymes. Next, multipoint mutations were introduced to glucosamine-6-phosphatesynthase (GlmS) to relieve the feedback inhibition. Then, a series of engineered strains were constructed by blocking the futile pathways by the deletion of the relevant genes. Finally, the culture conditions were optimized. LNT II titer was improved step-by-step from 0.53 to 5.52 g/L in shake-flask cultivations. Fed-batch culture of the final engineered strain produced 46.2 g/L of LNT II, with an LNT II productivity and content of 0.77 g/(L·h) and 0.95 g/g dry cell weight, respectively.
Collapse
Affiliation(s)
- Yingying Zhu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Li Wan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Jiawei Meng
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Guocong Luo
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Geng Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Hao Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
24
|
Park SA, Bhatia SK, Park HA, Kim SY, Sudheer PDVN, Yang YH, Choi KY. Bacillus subtilis as a robust host for biochemical production utilizing biomass. Crit Rev Biotechnol 2021; 41:827-848. [PMID: 33622141 DOI: 10.1080/07388551.2021.1888069] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bacillus subtilis is regarded as a suitable host for biochemical production owing to its excellent growth and bioresource utilization characteristics. In addition, the distinct endogenous metabolic pathways and the suitability of the heterologous pathways have made B. subtilis a robust and promising host for producing biochemicals, such as: bioalcohols; bioorganic acids (lactic acids, α-ketoglutaric acid, and γ-aminobutyric acid); biopolymers (poly(γ-glutamic acid, polyhydroxyalkanoates (PHA), and polysaccharides and monosaccharides (N-acetylglucosamine, xylooligosaccharides, and hyaluronic acid)); and bioflocculants. Also for producing oligopeptides and functional peptides, owing to its efficient protein secretion system. Several metabolic and genetic engineering techniques, such as target gene overexpression and inactivation of bypass pathways, have led to the improvement in production titers and product selectivity. In this review article, recent progress in the utilization of robust B. subtilis-based host systems for biomass conversion and biochemical production has been highlighted, and the prospects of such host systems are suggested.
Collapse
Affiliation(s)
- Seo A Park
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea
| | - Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, Republic of Korea.,Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul, Republic of Korea
| | - Hyun A Park
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea
| | - Seo Yeong Kim
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea
| | | | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, Republic of Korea.,Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul, Republic of Korea
| | - Kwon-Young Choi
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea.,Department of Environmental and Safety Engineering, College of Engineering, Ajou University, Suwon, South Korea
| |
Collapse
|
25
|
Synthetic small regulatory RNAs in microbial metabolic engineering. Appl Microbiol Biotechnol 2020; 105:1-12. [PMID: 33201273 DOI: 10.1007/s00253-020-10971-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 10/15/2020] [Accepted: 10/21/2020] [Indexed: 02/06/2023]
Abstract
Small regulatory RNAs (sRNAs) finely control gene expression in prokaryotes and synthetic sRNA has become a useful high-throughput approach to tackle current challenges in metabolic engineering because of its many advantages compared to conventional gene knockouts. In this review, we first focus on the modular structures of sRNAs and rational design strategies of synthetic sRNAs on the basis of their modular structures. The wide applications of synthetic sRNAs in bacterial metabolic engineering, with or without the aid of heterogeneously expressed Hfq protein, were also covered. In addition, we give attention to the improvements in implementing synthetic sRNAs, which make the synthetic sRNA strategy universally applicable in metabolic engineering and synthetic biology. KEY POINTS: • Synthetic sRNAs can be rationally designed based on modular structures of natural sRNAs. • Synthetic sRNAs were widely used for metabolic engineering in various microorganisms. • Several technological improvements made the synthetic sRNA strategy more applicable.
Collapse
|
26
|
Meng D, Wei X, Bai X, Zhou W, You C. Artificial in Vitro Synthetic Enzymatic Biosystem for the One-Pot Sustainable Biomanufacturing of Glucosamine from Starch and Inorganic Ammonia. ACS Catal 2020. [DOI: 10.1021/acscatal.0c03767] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Dongdong Meng
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, People’s Republic of China
| | - Xinlei Wei
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, People’s Republic of China
| | - Xue Bai
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, People’s Republic of China
| | - Wei Zhou
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, People’s Republic of China
| | - Chun You
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, People’s Republic of China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, People’s Republic of China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, People’s Republic of China
| |
Collapse
|
27
|
Titrating bacterial growth and chemical biosynthesis for efficient N-acetylglucosamine and N-acetylneuraminic acid bioproduction. Nat Commun 2020; 11:5078. [PMID: 33033266 PMCID: PMC7544899 DOI: 10.1038/s41467-020-18960-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 09/21/2020] [Indexed: 12/27/2022] Open
Abstract
Metabolic engineering facilitates chemical biosynthesis by rewiring cellular resources to produce target compounds. However, an imbalance between cell growth and bioproduction often reduces production efficiency. Genetic code expansion (GCE)-based orthogonal translation systems incorporating non-canonical amino acids (ncAAs) into proteins by reassigning non-canonical codons to ncAAs qualify for balancing cellular metabolism. Here, GCE-based cell growth and biosynthesis balance engineering (GCE-CGBBE) is developed, which is based on titrating expression of cell growth and metabolic flux determinant genes by constructing ncAA-dependent expression patterns. We demonstrate GCE-CGBBE in genome-recoded Escherichia coli Δ321AM by precisely balancing glycolysis and N-acetylglucosamine production, resulting in a 4.54-fold increase in titer. GCE-CGBBE is further expanded to non-genome-recoded Bacillus subtilis to balance growth and N-acetylneuraminic acid bioproduction by titrating essential gene expression, yielding a 2.34-fold increase in titer. Moreover, the development of ncAA-dependent essential gene expression regulation shows efficient biocontainment of engineered B. subtilis to avoid unintended proliferation in nature. An imbalance between cell growth and bioproduction of engineered microbes often reduces production efficiency. Here, the authors report genetic code expansion-based cell growth and biosynthesis balance engineering to achieve high levels production of N-acetylglucosamine in E. coli and N-acetylneuraminic acid in B. subtilis.
Collapse
|
28
|
Niu T, Lv X, Liu Y, Li J, Du G, Ledesma-Amaro R, Liu L. The elucidation of phosphosugar stress response in Bacillus subtilis guides strain engineering for high N-acetylglucosamine production. Biotechnol Bioeng 2020; 118:383-396. [PMID: 32965679 DOI: 10.1002/bit.27577] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 09/16/2020] [Accepted: 09/20/2020] [Indexed: 12/22/2022]
Abstract
Bacillus subtilis is a preferred microbial host for the industrial production of nutraceuticals and a promising candidate for the synthesis of functional sugars, such as N-acetylglucosamine (GlcNAc). Previously, a GlcNAc-overproducer B. subtilis SFMI was constructed using glmS ribozyme dual-regulatory tool. Herein, we further engineered to enhance carbon flux from glucose towards GlcNAc synthesis. As a result, the increased flux towards GlcNAc synthesis triggered phosphosugar stress response, which caused abnormal cell growth. Unfortunately, the mechanism of phosphosugar stress response had not been elucidated in B. subtilis. To reveal the stress mechanism and overcome its negative effect in bioproduction, we performed comparative transcriptome analysis. The results indicate that cells slow glucose utilization by repression of glucose import and accelerate catabolic reactions of phosphosugar. To verify these results, we overexpressed the phosphatase YwpJ, which relieved phosphosugar stress and allowed us to identify the enzyme responsible for GlcNAc synthesis from GlcNAc 6-phosphate. In addition, the deletion of nagBB and murQ, responsible for GlcNAc precursor degradation, further improved GlcNAc synthesis. The best engineered strain, B. subtilis FMIP34, increased GlcNAc titer from 11.5 to 26.1 g/L in shake flasks and produced 87.5 g/L GlcNAc in 30-L fed-batch bioreactor. Our results not only elucidate, for the first time, the phosphosugar stress response mechanism in B. subtilis, but also demonstrate how the combination of rational metabolic engineering with novel insights into physiology and metabolism allows the construction of highly efficient microbial cell factories for the production of high-value chemicals.
Collapse
Affiliation(s)
- Tengfei Niu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China
| | - Jianghua Li
- Science Center for Future Foods, Jiangnan University, Wuxi, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China
| | - Rodrigo Ledesma-Amaro
- Department of Bioengineering, Imperial College Centre for Synthetic Biology, Imperial College London, London, UK
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China
| |
Collapse
|
29
|
Enhancement of Production of D-Glucosamine in Escherichia coli by Blocking Three Pathways Involved in the Consumption of GlcN and GlcNAc. Mol Biotechnol 2020; 62:387-399. [PMID: 32572810 DOI: 10.1007/s12033-020-00257-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2020] [Indexed: 10/24/2022]
Abstract
D-Glucosamine is a commonly used dietary supplement that promotes cartilage health in humans. Metabolic flux analysis showed that D-glucosamine production could be increased by blocking three pathways involved in the consumption of glucosamine-6-phosphate and acetylglucosamine-6-phosphate. By homologous single-exchange, two key genes (nanE and murQ) of Escherichia coli BL21 were knocked out, respectively. The D-glucosamine yields of the engineered strains E. coli BL21ΔmurQ and E. coli BL21ΔnanE represented increases by factors of 2.14 and 1.79, respectively. Meanwhile, for bifunctional gene glmU, we only knocked out its glucosamine-1-phosphate acetyltransferase domain by 3D structural analysis to keep the engineered strain E. coli BL21glmU-Δgpa survival, which resulted in an increase in the production of D-glucosamine by a factor of 2.16. Moreover, for further increasing D-glucosamine production, two genes encoding rate-limiting enzymes, named glmS and gna1, were coexpressed by an RBS sequence in those engineered strains. The total concentrations of D-glucosamine in E. coli BL21 glmU-Δgpa', E. coli BL21ΔmurQ', and E. coli BL21ΔnanE' were 2.65 g/L, 1.73 g/L, and 1.38 g/L, which represented increases by factors of 8.83, 5.76, and 3.3, respectively.
Collapse
|
30
|
Coussement P, Bauwens D, Peters G, Maertens J, De Mey M. Mapping and refactoring pathway control through metabolic and protein engineering: The hexosamine biosynthesis pathway. Biotechnol Adv 2020; 40:107512. [DOI: 10.1016/j.biotechadv.2020.107512] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 08/07/2019] [Accepted: 09/30/2019] [Indexed: 01/14/2023]
|
31
|
Lv X, Wu Y, Tian R, Gu Y, Liu Y, Li J, Du G, Ledesma-Amaro R, Liu L. Synthetic metabolic channel by functional membrane microdomains for compartmentalized flux control. Metab Eng 2020; 59:106-118. [DOI: 10.1016/j.ymben.2020.02.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 02/17/2020] [Accepted: 02/17/2020] [Indexed: 10/24/2022]
|
32
|
Feng Y, Yao M, Wang Y, Ding M, Zha J, Xiao W, Yuan Y. Advances in engineering UDP-sugar supply for recombinant biosynthesis of glycosides in microbes. Biotechnol Adv 2020; 41:107538. [PMID: 32222423 DOI: 10.1016/j.biotechadv.2020.107538] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/16/2020] [Accepted: 03/20/2020] [Indexed: 12/21/2022]
Abstract
Plant glycosides are of great interest for industries. Glycosylation of plant secondary metabolites can greatly improve their solubility, biological activity, or stability. This allows some plant glycosides to be used as food additives, cosmetic products, health products, antisepsis and anti-cancer drugs. With the continuous expansion of market demand, a variety of biological fermentation technologies has emerged. This review focuses on recombinant microbial biosynthesis of plant glycosides, which uses UDP-sugars as precursors, and summarizes various strategies to increase the yield of glycosides with a key concentration on UDP-sugar supply based on four aspects, i.e., gene overexpression, UDP-sugar recycling, mixed fermentation, and carbon co-utilization. Meanwhile, the application potential and advantages of various techniques are introduced, which provide guidance to the development of high-yield strains for recombinant microbial production of plant glycosides. Finally, the technical challenges of glycoside biosynthesis are pointed out with discussions on future directions of improving the yield of recombinantly synthesized glycosides.
Collapse
Affiliation(s)
- Yueyang Feng
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Mingdong Yao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Ying Wang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Mingzhu Ding
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Jian Zha
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
| | - Wenhai Xiao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China.
| | - Yingjin Yuan
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| |
Collapse
|
33
|
Niu T, Lv X, Liu Z, Li J, Du G, Liu L. Synergetic engineering of central carbon and nitrogen metabolism for the production ofN‐acetylglucosamine inBacillus subtilis. Biotechnol Appl Biochem 2020; 67:123-132. [DOI: 10.1002/bab.1845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/23/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Tengfei Niu
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Zhenmin Liu
- State Key Laboratory of Dairy BiotechnologyShanghai Engineering Research Center of Dairy BiotechnologyDairy Research InstituteBright Dairy & Food Co., Ltd. Shanghai People's Republic of China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| |
Collapse
|
34
|
Multi-enzyme systems and recombinant cells for synthesis of valuable saccharides: Advances and perspectives. Biotechnol Adv 2019; 37:107406. [DOI: 10.1016/j.biotechadv.2019.06.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 05/30/2019] [Accepted: 06/08/2019] [Indexed: 02/07/2023]
|
35
|
CRISPR/Cas9-Assisted Seamless Genome Editing in Lactobacillus plantarum and Its Application in N-Acetylglucosamine Production. Appl Environ Microbiol 2019; 85:AEM.01367-19. [PMID: 31444197 DOI: 10.1128/aem.01367-19] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/14/2019] [Indexed: 12/30/2022] Open
Abstract
Lactobacillus plantarum is a potential starter and health-promoting probiotic bacterium. Effective, precise, and diverse genome editing of Lactobacillus plantarum without introducing exogenous genes or plasmids is of great importance. In this study, CRISPR/Cas9-assisted double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA) recombineering was established in L. plantarum WCFS1 to seamlessly edit the genome, including gene knockouts, insertions, and point mutations. To optimize our editing method, phosphorothioate modification was used to improve the dsDNA insertion, and adenine-specific methyltransferase was used to improve the ssDNA recombination efficiency. These strategies were applied to engineer L. plantarum WCFS1 toward producing N-acetylglucosamine (GlcNAc). nagB was truncated to eliminate the reverse reaction of fructose-6-phosphate (F6P) to glucosamine 6-phosphate (GlcN-6P). Riboswitch replacement and point mutation in glmS1 were introduced to relieve feedback repression. The resulting strain produced 797.3 mg/liter GlcNAc without introducing exogenous genes or plasmids. This strategy may contribute to the available methods for precise and diverse genetic engineering in lactic acid bacteria and boost strain engineering for more applications.IMPORTANCE CRISPR/Cas9-assisted recombineering is restricted in lactic acid bacteria because of the lack of available antibiotics and vectors. In this study, a seamless genome editing method was carried out in Lactobacillus plantarum using CRISPR/Cas9-assisted double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA) recombineering, and recombination efficiency was effectively improved by endogenous adenine-specific methyltransferase overexpression. L. plantarum WCFS1 produced 797.3 mg/liter N-acetylglucosamine (GlcNAc) through reinforcement of the GlcNAc pathway, without introducing exogenous genes or plasmids. This seamless editing strategy, combined with the potential exogenous GlcNAc-producing pathway, makes this strain an attractive candidate for industrial use in the future.
Collapse
|
36
|
Microbial production of sialic acid and sialylated human milk oligosaccharides: Advances and perspectives. Biotechnol Adv 2019; 37:787-800. [DOI: 10.1016/j.biotechadv.2019.04.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 04/13/2019] [Accepted: 04/23/2019] [Indexed: 12/21/2022]
|
37
|
Deng C, Lv X, Liu Y, Li J, Lu W, Du G, Liu L. Metabolic engineering of Corynebacterium glutamicum S9114 based on whole-genome sequencing for efficient N-acetylglucosamine synthesis. Synth Syst Biotechnol 2019; 4:120-129. [PMID: 31198861 PMCID: PMC6558094 DOI: 10.1016/j.synbio.2019.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 05/30/2019] [Accepted: 05/30/2019] [Indexed: 12/26/2022] Open
Abstract
Glucosamine (GlcN) and its acetylated derivative N-acetylglucosamine (GlcNAc) are widely used in the pharmaceutical industries. Here, we attempted to achieve efficient production of GlcNAc via genomic engineering of Corynebacterium glutamicum. Specifically, we ligated the GNA1 gene, which converts GlcN-6-phosphate to GlcNAc-6-phosphate by transferring the acetyl group in Acetyl-CoA to the amino group of GlcN-6-phosphate, into the plasmid pJYW4 and then transformed this recombinant vector into the C. glutamicum ATCC 13032, ATCC 13869, ATCC 14067, and S9114 strains, and we assessed the GlcNAc titers at 0.5 g/L, 1.2 g/L, 0.8 g/L, and 3.1 g/L from each strain, respectively. This suggested that there were likely to be significant differences among the key genes in the glutamate and GlcNAc synthesis pathways of these C. glutamicum strains. Therefore, we performed whole genome sequencing of the S9114 strain, which has not been previously published, and found that there are many differences among the genes in the glutamate and GlcNAc synthesis pathways among the four strains tested. Next, nagA (encoding GlcNAc-6-phosphate deacetylase) and gamA (encoding GlcN-6-phosphate deaminase) were deleted in C. glutamicum S9114 to block the catabolism of intracellular GlcNAc, leading to a 54.8% increase in GlcNAc production (from 3.1 to 4.8 g/L) when grown in a shaker flask. In addition, lactate synthesis was blocked by knockout of ldh (encoding lactate dehydrogenase); thus, further increasing the GlcNAc titer to 5.4 g/L. Finally, we added a key gene of the GlcN synthetic pathway, glmS, from different sources into the expression vector pJYW-4-ceN, and the resulting recombinant strain CGGN2-GNA1-CgglmS produced the GlcNAc titer of 6.9 g/L. This is the first report concerning the metabolic engineering of C. glutamicum, and the results of this study provide a good starting point for further metabolic engineering to achieve industrial-scale production of GlcNAc.
Collapse
Affiliation(s)
- Chen Deng
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Wei Lu
- Shandong Runde Biotechnology CO., LTD, Taian, 271200, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| |
Collapse
|
38
|
Han L, Cui W, Suo F, Miao S, Hao W, Chen Q, Guo J, Liu Z, Zhou L, Zhou Z. Development of a novel strategy for robust synthetic bacterial promoters based on a stepwise evolution targeting the spacer region of the core promoter in Bacillus subtilis. Microb Cell Fact 2019; 18:96. [PMID: 31142347 PMCID: PMC6540529 DOI: 10.1186/s12934-019-1148-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 05/22/2019] [Indexed: 01/06/2023] Open
Abstract
Background Promoter evolution by synthetic promoter library (SPL) is a powerful approach to development of functional synthetic promoters to synthetic biology. However, it requires much tedious and time-consuming screenings because of the plethora of different variants in SPL. Actually, a large proportion of mutants in the SPL are significantly lower in strength, which contributes only to fabrication of a promoter library with a continuum of strength. Thus, to effectively obtain the evolved synthetic promoter exhibiting higher strength, it is essential to develop novel strategies to construct mutant library targeting the pivotal region rather than the arbitrary region of the template promoter. In this study, a strategy termed stepwise evolution targeting the spacer of core promoter (SETarSCoP) was established in Bacillus subtilis to effectively evolve the strength of bacterial promoter. Results The native promoter, PsrfA, from B. subtilis, which exhibits higher strength than the strong promoter P43, was set as the parental template. According to the comparison of conservation of the spacer sequences between − 35 box and − 10 box among a set of strong and weak native promoter, it revealed that 7-bp sequence immediately upstream of the − 10 box featured in the regulation of promoter strength. Based on the conservative feature, two rounds of consecutive evolution were performed targeting the hot region of PsrfA. In the first round, a primary promoter mutation library (pPML) was constructed by mutagenesis targeting the 3-bp sequence immediately upstream of the − 10 box of the PsrfA. Subsequently, four evolved mutants from pPML were selected to construction of four secondary promoter mutation libraries (sPMLs) based on mutagenesis of the 4-bp sequence upstream of the first-round target. After the consecutive two-step evolution, the mutant PBH4 was identified and verified to be a highly evolved synthetic promoter. The strength of PBH4 was higher than PsrfA by approximately 3 times. Moreover, PBH4 also exhibited broad suitability for different cargo proteins, such as β-glucuronidase and nattokinase. The proof-of-principle test showed that SETarSCoP successfully evolved both constitutive and inducible promoters. Conclusion Comparing with the commonly used SPL strategy, SETarSCoP facilitates the evolution process to obtain strength-evolved synthetic bacterial promoter through fabrication and screening of small-scale mutation libraries. This strategy will be a promising method to evolve diverse bacterial promoters to expand the toolbox for synthetic biology. Electronic supplementary material The online version of this article (10.1186/s12934-019-1148-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Laichuang Han
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Wenjing Cui
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China.
| | - Feiya Suo
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Shengnan Miao
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Wenliang Hao
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Qiaoqing Chen
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Junling Guo
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Zhongmei Liu
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Li Zhou
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Zhemin Zhou
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, 214122, Jiangsu, China.
| |
Collapse
|
39
|
Ma W, Liu Y, Lv X, Li J, Du G, Liu L. Combinatorial pathway enzyme engineering and host engineering overcomes pyruvate overflow and enhances overproduction of N-acetylglucosamine in Bacillus subtilis. Microb Cell Fact 2019; 18:1. [PMID: 30609921 PMCID: PMC6318901 DOI: 10.1186/s12934-018-1049-x] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 12/24/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Glucosamine-6-phosphate N-acetyltransferase (GNA1) is the key enzyme that causes overproduction of N-acetylglucosamine in Bacillus subtilis. Previously, we increased GlcNAc production by promoting the expression of GNA1 from Caenorhabditis elegans (CeGNA1) in an engineered B. subtilis strain BSGN12. In this strain overflow metabolism to by-products acetoin and acetate had been blocked by mutations, however pyruvate accumulated as an overflow metabolite. Although overexpression of CeGNA1 drove carbon flux from pyruvate to the GlcNAc synthesis pathway and decreased pyruvate accumulation, the residual pyruvate reduced the intracellular pH, resulting in inhibited CeGNA1 activity and limited GlcNAc production. RESULTS In this study, we attempted to further overcome pyruvate overflow by enzyme engineering and host engineering for enhanced GlcNAc production. To this end, the key enzyme CeGNA1 was evolved through error-prone PCR under pyruvate stress to enhance its catalytic activity. Then, the urease from Bacillus paralicheniformis was expressed intracellularly to neutralize the intracellular pH, making it more robust in growth and more efficient in GlcNAc production. It was found that the activity of mutant CeGNA1 increased by 11.5% at pH 6.5-7.5, with the catalytic efficiency increasing by 27.5% to 1.25 s-1 µM-1. Modulated expression of urease increased the intracellular pH from 6.0 to 6.8. The final engineered strain BSGN13 overcame pyruvate overflow, produced 25.6 g/L GlcNAc with a yield of 0.43 g GlcNAc/g glucose in a shake flask fermentation and produced 82.5 g/L GlcNAc with a yield of 0.39 g GlcNAc/g glucose by fed-batch fermentation, which was 1.7- and 1.2-times, respectively, of the yield achieved previously. CONCLUSIONS This study highlights a strategy that combines pathway enzyme engineering and host engineering to resolve overflow metabolism in B. subtilis for the overproduction of GlcNAc. By means of modulated expression of urease reduced pyruvate burden, conferred bacterial survival fitness, and enhanced GlcNAc production, all of which improved our understanding of co-regulation of cell growth and metabolism to construct more efficient B. subtilis cell factories.
Collapse
Affiliation(s)
- Wenlong Ma
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China. .,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China.
| |
Collapse
|
40
|
de Assis LJ, Manfiolli A, Mattos E, Fabri JHTM, Malavazi I, Jacobsen ID, Brock M, Cramer RA, Thammahong A, Hagiwara D, Ries LNA, Goldman GH. Protein Kinase A and High-Osmolarity Glycerol Response Pathways Cooperatively Control Cell Wall Carbohydrate Mobilization in Aspergillus fumigatus. mBio 2018; 9:e01952-18. [PMID: 30538182 PMCID: PMC6299480 DOI: 10.1128/mbio.01952-18] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 11/06/2018] [Indexed: 02/07/2023] Open
Abstract
Aspergillus fumigatus mitogen-activated protein kinases (MAPKs) are involved in maintaining the normal morphology of the cell wall and providing resistance against cell wall-damaging agents. Upon cell wall stress, cell wall-related sugars need to be synthesized from carbohydrate storage compounds. Here we show that this process is dependent on cAMP-dependent protein kinase A (PKA) activity and regulated by the high-osmolarity glycerol response (HOG) MAPKs SakA and MpkC. These protein kinases are necessary for normal accumulation/degradation of trehalose and glycogen, and the lack of these genes reduces glucose uptake and glycogen synthesis. Alterations in glycogen synthesis were observed for the sakA and mpkC deletion mutants, which also displayed alterations in carbohydrate exposure on the cell wall. Carbohydrate mobilization is controlled by SakA interaction with PkaC1 and PkaR, suggesting a putative mechanism where the PkaR regulatory subunit leaves the complex and releases the SakA-PkaC1 complex for activation of enzymes involved in carbohydrate mobilization. This work reveals the communication between the HOG and PKA pathways for carbohydrate mobilization for cell wall construction.IMPORTANCEAspergillus fumigatus is an opportunistic human pathogen causing allergic reactions or systemic infections such as invasive pulmonary aspergillosis, especially in immunocompromised patients. The fungal cell wall is the main component responsible for recognition by the immune system, due to the specific composition of polysaccharide carbohydrates exposed on the surface of the fungal cell wall called pathogen-associated molecular patterns (PAMPs). Key enzymes in the fungal cell wall biosynthesis are a good target for fungal drug development. This report elucidates the cooperation between the HOG and PKA pathways in the mobilization of carbohydrates for fungal cell wall biosynthesis. We suggest that the reduced mobilization of simple sugars causes defects in the structure of the fungal cell wall. In summary, we propose that SakA is important for PKA activity, therefore regulating the availability and mobilization of monosaccharides for fungal cell wall biosynthesis during cell wall damage and the osmotic stress response.
Collapse
Affiliation(s)
- Leandro José de Assis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Adriana Manfiolli
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Eliciane Mattos
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - João H T Marilhano Fabri
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Paulo, Brazil
| | - Iran Malavazi
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Paulo, Brazil
| | - Ilse D Jacobsen
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
| | - Matthias Brock
- Fungal Genetics and Biology Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Robert A Cramer
- Geisel School of Medicine at Dartmouth, Department of Microbiology and Immunology, Hanover, New Hampshire, USA
| | - Arsa Thammahong
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Daisuke Hagiwara
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | | | - Gustavo Henrique Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| |
Collapse
|
41
|
Leistra AN, Curtis NC, Contreras LM. Regulatory non-coding sRNAs in bacterial metabolic pathway engineering. Metab Eng 2018; 52:190-214. [PMID: 30513348 DOI: 10.1016/j.ymben.2018.11.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 10/31/2018] [Accepted: 11/29/2018] [Indexed: 12/11/2022]
Abstract
Non-coding RNAs (ncRNAs) are versatile and powerful controllers of gene expression that have been increasingly linked to cellular metabolism and phenotype. In bacteria, identified and characterized ncRNAs range from trans-acting, multi-target small non-coding RNAs to dynamic, cis-encoded regulatory untranslated regions and riboswitches. These native regulators have inspired the design and construction of many synthetic RNA devices. In this work, we review the design, characterization, and impact of ncRNAs in engineering both native and exogenous metabolic pathways in bacteria. We also consider the opportunities afforded by recent high-throughput approaches for characterizing sRNA regulators and their corresponding networks to showcase their potential applications and impact in engineering bacterial metabolism.
Collapse
Affiliation(s)
- Abigail N Leistra
- McKetta Department of Chemical Engineering, University of Texas at Austin, 200 E. Dean Keeton Street Stop C0400, Austin, TX 78712, USA
| | - Nicholas C Curtis
- McKetta Department of Chemical Engineering, University of Texas at Austin, 200 E. Dean Keeton Street Stop C0400, Austin, TX 78712, USA
| | - Lydia M Contreras
- McKetta Department of Chemical Engineering, University of Texas at Austin, 200 E. Dean Keeton Street Stop C0400, Austin, TX 78712, USA.
| |
Collapse
|
42
|
Advances and prospects of Bacillus subtilis cellular factories: From rational design to industrial applications. Metab Eng 2018; 50:109-121. [DOI: 10.1016/j.ymben.2018.05.006] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 05/02/2018] [Accepted: 05/10/2018] [Indexed: 01/29/2023]
|
43
|
Niu T, Liu Y, Li J, Koffas M, Du G, Alper HS, Liu L. Engineering a Glucosamine-6-phosphate Responsive glmS Ribozyme Switch Enables Dynamic Control of Metabolic Flux in Bacillus subtilis for Overproduction of N-Acetylglucosamine. ACS Synth Biol 2018; 7:2423-2435. [PMID: 30138558 DOI: 10.1021/acssynbio.8b00196] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacillus subtilis is a typical industrial microorganism and is widely used in industrial biotechnology, particularly for nutraceutical production. There are many studies on the static metabolic engineering of B. subtilis, whereas there are few reports on dynamic metabolic engineering due to the lack of appropriate elements. Here, we established a dynamic reprogramming strategy for reconstructing metabolic networks in B. subtilis, using a typical nutraceutical, N-acetylglucosamine (GlcNAc), as a model product and the glmS (encoding glucosamine-6-phosphate synthase) ribozyme as an engineering element. First, a trp terminator was introduced to effectively release the glmS ribozyme feedback inhibition. Further, we engineered the native glucosamine-6-phosphate (GlcN6P) responsive glmS ribozyme switch to dynamically control the metabolic flux in B. subtilis for overproduction of GlcNAc. With GlcN6P as a ligand, the native sensor glmS ribozyme is integrated at the 5'- of phosphoglucosamine mutase and 6-phosphofructokinase genes to decrease the flux dynamically toward the peptidoglycan synthesis and glycolysis pathway, respectively. The glmS ribozyme mutant M5 ( glmS ribozyme cleavage site AG → GG) with decreased ribozyme activity is integrated at the 5'- of glucose-6-phosphate isomerase gene to increase the flux dynamically toward the GlcNAc synthesis pathway. This strategy increased the GlcNAc titer from 9.24 to 18.45 g/L, and the specific GlcNAc productivity from 0.53 to 1.21 g GlcNAc/g cell. Since GlcN6P is involved in the biosynthesis of various products, here the developed strategy for multiple target dynamic engineering of metabolic pathways can be generally used in B. subtilis and other industrial microbes for chemical production.
Collapse
Affiliation(s)
- Tengfei Niu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Mattheos Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Hal S. Alper
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
44
|
Gu Y, Lv X, Liu Y, Li J, Du G, Chen J, Rodrigo LA, Liu L. Synthetic redesign of central carbon and redox metabolism for high yield production of N-acetylglucosamine in Bacillus subtilis. Metab Eng 2018; 51:59-69. [PMID: 30343048 DOI: 10.1016/j.ymben.2018.10.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 09/26/2018] [Accepted: 10/01/2018] [Indexed: 01/06/2023]
Abstract
One of the primary goals of microbial metabolic engineering is to achieve high titer, yield and productivity (TYP) of engineered strains. This TYP index requires optimized carbon flux toward desired molecule with minimal by-product formation. De novo redesign of central carbon and redox metabolism holds great promise to alleviate pathway bottleneck and improve carbon and energy utilization efficiency. The engineered strain, with the overexpression or deletion of multiple genes, typically can't meet the TYP index, due to overflow of central carbon and redox metabolism that compromise the final yield, despite a high titer or productivity might be achieved. To solve this challenge, we reprogramed the central carbon and redox metabolism of Bacillus subtilis and achieved high TYP production of N-acetylglucosamine. Specifically, a "push-pull-promote" approach efficiently reduced the overflown acetyl-CoA flux and eliminated byproduct formation. Four synthetic NAD(P)-independent metabolic routes were introduced to rewire the redox metabolism to minimize energy loss. Implementation of these genetic strategies led us to obtain a B. subtilis strain with superior TYP index. GlcNAc titer in shake flask was increased from 6.6 g L-1 to 24.5 g L-1, the yield was improved from 0.115 to 0.468 g GlcNAc g-1 glucose, and the productivity was increased from 0.274 to 0.437 g L-1 h-1. These titer and yield are the highest levels ever reported and, the yield reached 98% of the theoretical pathway yield (0.478 g g-1 glucose). The synthetic redesign of carbon metabolism and redox metabolism represent a novel and general metabolic engineering strategy to improve the performance of microbial cell factories.
Collapse
Affiliation(s)
- Yang Gu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jian Chen
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | | | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
| |
Collapse
|
45
|
Metabolic engineering of capsular polysaccharides. Emerg Top Life Sci 2018; 2:337-348. [DOI: 10.1042/etls20180003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 06/11/2018] [Accepted: 06/27/2018] [Indexed: 11/17/2022]
Abstract
With rising concerns about sustainable practices, environmental complications, and declining resources, metabolic engineers are transforming microorganisms into cellular factories for producing capsular polysaccharides (CPSs). This review provides an overview of strategies employed for the metabolic engineering of heparosan, chondroitin, hyaluronan, and polysialic acid — four CPSs that are of interest for manufacturing a variety of biomedical applications. Methods described include the exploitation of wild-type and engineered native CPS producers, as well as genetically engineered heterologous hosts developed through the improvement of naturally existing pathways or newly (de novo) designed ones. The implementation of methodologies like gene knockout, promoter engineering, and gene expression level control has resulted in multiple-fold improvements in CPS fermentation titers compared with wild-type strains, and substantial increases in productivity, reaching as high as 100% in some cases. Optimization of these biotechnological processes can permit the adoption of industrially competitive engineered microorganisms to replace traditional sources that are generally toxic, unreliable, and inconsistent in product quality.
Collapse
|
46
|
Wu Y, Chen T, Liu Y, Lv X, Li J, Du G, Ledesma-Amaro R, Liu L. CRISPRi allows optimal temporal control of N-acetylglucosamine bioproduction by a dynamic coordination of glucose and xylose metabolism in Bacillus subtilis. Metab Eng 2018; 49:232-241. [DOI: 10.1016/j.ymben.2018.08.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/15/2018] [Accepted: 08/30/2018] [Indexed: 10/28/2022]
|
47
|
Zhang X, Liu Y, Liu L, Wang M, Li J, Du G, Chen J. Modular pathway engineering of key carbon‐precursor supply‐pathways for improved
N
‐acetylneuraminic acid production in
Bacillus subtilis. Biotechnol Bioeng 2018; 115:2217-2231. [DOI: 10.1002/bit.26743] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/23/2018] [Accepted: 06/05/2018] [Indexed: 12/22/2022]
Affiliation(s)
- Xiaolong Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
| | - Miao Wang
- School of Food Science and Technology, Jiangnan UniversityWuxi China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
| | - Jian Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan UniversityWuxi China
- State Key Laboratory of Food Science and Technology, Jiangnan UniversityWuxi China
| |
Collapse
|
48
|
Ma W, Liu Y, Shin HD, Li J, Chen J, Du G, Liu L. Metabolic engineering of carbon overflow metabolism of Bacillus subtilis for improved N-acetyl-glucosamine production. BIORESOURCE TECHNOLOGY 2018; 250:642-649. [PMID: 29220808 DOI: 10.1016/j.biortech.2017.10.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 10/02/2017] [Accepted: 10/04/2017] [Indexed: 05/09/2023]
Abstract
Bacillus subtilis is widely used as cell factories for the production of important industrial biochemicals. Although many studies have demonstrated the effects of organic acidic byproducts, such as acetate, on microbial fermentation, little is known about the effects of blocking the neutral byproduct overflow, such as acetoin, on bioproduction. In this study, we focused on the influences of modulating overflow metabolism on the production of N-acetyl-d-glucosamine (GlcNAc) in engineered B. subtilis. We found that acetoin overflow competes with GlcNAc production, and blocking acetoin overflow increased GlcNAc titer and yield by 1.38- and 1.39-fold, reaching 48.9 g/L and 0.32 g GlcNAc/g glucose, respectively. Further blocking acetate overflow inhibited cell growth and GlcNAc production may be induced by inhibiting glucose uptake. Taken together, our results show that blocking acetoin overflow is a promising strategy for enhancing GlcNAc production. The strategies developed in this work may be useful for engineering strains of B. subtilis for producing other important biochemicals.
Collapse
Affiliation(s)
- Wenlong Ma
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Hyun-Dong Shin
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta 30332, USA
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jian Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Guocheng Du
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
49
|
Ling M, Liu Y, Li J, Shin HD, Chen J, Du G, Liu L. Combinatorial promoter engineering of glucokinase and phosphoglucoisomerase for improved N-acetylglucosamine production in Bacillus subtilis. BIORESOURCE TECHNOLOGY 2017; 245:1093-1102. [PMID: 28946392 DOI: 10.1016/j.biortech.2017.09.063] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 06/07/2023]
Abstract
In previous work, a recombinant Bacillus subtilis strain was successfully constructed for microbial production of N-acetylglucosamine (GlcNAc). In this study, GlcNAc titer was further improved by combinatorial promoter engineering of key genes glck encoding glucokinase and pgi encoding phosphoglucoisomerase. First, three promoters including constitutive promoter P43, xylose inducible promoter PxylA, and isopropyl-β-d-thiogalactoside inducible Pgrac were used to replace the native promoters of glcK and pgi, yielding 12 recombinant strains. It was found that when glcK and pgi were both under the control of promoter PxylA, the highest GlcNAc titer in 3-L fed-batch bioreactor reached 35.12g/L, which was 52.6% higher than that of the initial host. Next, the transcriptional levels of the related genes in glycolysis, GlcNAc synthesis pathway, peptidoglycan synthesis pathway, and pentose phosphate pathway were investigated by quantitative real-time PCR analysis. Fine-tuning upper GlcNAc synthesis pathway by combinatorial promoter substitution significantly enhanced GlcNAc production in engineered B. subtilis.
Collapse
Affiliation(s)
- Meixi Ling
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Hyun-Dong Shin
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta 30332, USA
| | - Jian Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
50
|
Han L, Suo F, Jiang C, Gu J, Li N, Zhang N, Cui W, Zhou Z. Fabrication and characterization of a robust and strong bacterial promoter from a semi-rationally engineered promoter library in Bacillus subtilis. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.06.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|