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Liu Y, Wang J, Huang JB, Li XF, Chen Y, Liu K, Zhao M, Huang XL, Gao XL, Luo YN, Tao W, Wu J, Xue ZL. Advances in regulating vitamin K 2 production through metabolic engineering strategies. World J Microbiol Biotechnol 2023; 40:8. [PMID: 37938463 DOI: 10.1007/s11274-023-03828-5] [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: 09/28/2023] [Accepted: 11/02/2023] [Indexed: 11/09/2023]
Abstract
Vitamin K2 (menaquinone, VK2, MK) is an essential lipid-soluble vitamin that plays critical roles in inhibiting cell ferroptosis, improving blood clotting, and preventing osteoporosis. The increased global demand for VK2 has inspired interest in novel production strategies. In this review, various novel metabolic regulation strategies, including static and dynamic metabolic regulation, are summarized and discussed. Furthermore, the advantages and disadvantages of both strategies are analyzed in-depth to highlight the bottlenecks facing microbial VK2 production on an industrial scale. Finally, advanced metabolic engineering biotechnology for future microbial VK2 production will also be discussed. In summary, this review provides in-depth information and offers an outlook on metabolic engineering strategies for VK2 production.
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Affiliation(s)
- Yan Liu
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China.
- Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, 241000, Wuhu, China.
| | - Jian Wang
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
| | - Jun-Bao Huang
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
| | - Xiang-Fei Li
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
- Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, 241000, Wuhu, China
| | - Yu Chen
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
- Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, 241000, Wuhu, China
| | - Kun Liu
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
- Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, 241000, Wuhu, China
| | - Ming Zhao
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China.
- Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, 241000, Wuhu, China.
| | - Xi-Lin Huang
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
| | - Xu-Li Gao
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
| | - Ya-Ni Luo
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
| | - Wei Tao
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
| | - Jing Wu
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
| | - Zheng-Lian Xue
- College of Biology and Food Engineering, Anhui Polytechnic University, 241000, Wuhu, China
- Anhui Engineering Laboratory for Industrial Microbiology Molecular Breeding, 241000, Wuhu, China
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Kim SH, Hwang JH, Kim HJ, Oh SJ, Kim HJ, Shin N, Kim SH, Park JH, Bhatia SK, Yang YH. Enhancement of biohydrogen production in Clostridium acetobutylicum ATCC 824 by overexpression of glyceraldehyde-3-phosphate dehydrogenase gene. Enzyme Microb Technol 2023; 168:110244. [PMID: 37196383 DOI: 10.1016/j.enzmictec.2023.110244] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/28/2023] [Accepted: 05/01/2023] [Indexed: 05/19/2023]
Abstract
In the dark fermentation of hydrogen, development of production host is crucial as bacteria act on substrates and produce hydrogen. The present study aimed to improve hydrogen production through the development of Clostridium acetobutylicum as a superior biohydrogen producer. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), which produces NADH/NADPH for metabolites and energy in primary pathways, was introduced to enhance hydrogen production. The strain CAC824-G containing gapC that encodes GAPDH showed a 66.3 % higher hydrogen production than the wild-type strain, with increased NADH and NADPH pools. Glucose consumption and other byproducts, such as acetone, butanol, and ethanol, were also high in CAC824-G. Overexpression of gapC resulted in increased hydrogen production with sugars obtained from different biomass, even in the presence of inhibitors such as vanillin, 5-hydroxymethylfufural, acetic acid, and formic acid. Our results imply that overexpression of gapC in Clostridium is possible to expand the production of the reported biochemicals to produce hydrogen.
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Affiliation(s)
- Sang Hyun Kim
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Jeong Hyeon Hwang
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Hyun Joong Kim
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Suk Jin Oh
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Hyun Jin Kim
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Nara Shin
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Sang-Hyoun Kim
- School of Civil and Environmental Engineering, Yonsei University, 50, Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Jeong-Hoon Park
- Sustainable Technology and Wellness R&D Group, Korea Institute of Industrial Technology (KITECH), Jeju-si 63243, Republic of Korea
| | - Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea; Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul 05029, Republic of Korea.
| | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea; Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul 05029, Republic of Korea.
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Liu CL, Dong HG, Xue K, Sun L, Yang Y, Liu X, Li Y, Bai Z, Tan TW. Metabolic Engineering Mevalonate Pathway Mediated by RNA Scaffolds for Mevalonate and Isoprene Production in Escherichia coli. ACS Synth Biol 2022; 11:3305-3317. [PMID: 36198145 DOI: 10.1021/acssynbio.2c00226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Co-localizing biochemical processes is a great strategy when expressing the heterologous metabolic pathway for product biosynthesis. The RNA scaffold is a flexible and efficient synthetic compartmentalization method to co-localize the enzymes involved in the metabolic pathway by binding to the specific RNA, binding domains fused with the engineered enzymes. Herein, we designed two artificial RNA scaffold structures─0D RNA scaffolds and 2D RNA scaffolds─using the reported aptamers PP7 and BIV-Tat and the corresponding RNA-binding domains (RBDs). We verified the interaction of the RBD and RNA aptamer in vitro and in vivo. Then, we determined the efficiencies of these RNA scaffolds by co-localizing fluorescent proteins. We employed the RNA scaffolds combined with the enzyme fusion strategies to increase the metabolic flux involved in the enzymes of the mevalonate pathway for mevalonate and isoprene production. Compared with the no RNA scaffold strain, the mevalonate levels of the 0D RNA scaffolds and 2D RNA scaffolds increased by 84.1% (3.13 ± 0.03 g/L) and 76.5% (3.00 ± 0.09 g/L), respectively. We applied the 0D RNA scaffolds for increasing the isoprene production by localizing the enzymes involved in a heterologous multi-enzyme pathway. When applying the RNA scaffolds for co-localizing the enzymes mvaE and mvaS, the isoprene production reached to 609.3 ± 57.9 mg/L, increasing by 142% compared with the no RNA scaffold strain. Our results indicate that the RNA scaffold is a powerful tool for improving the efficiencies of the reaction process in the metabolic pathway.
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Affiliation(s)
- Chun-Li Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Hong-Gang Dong
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Kai Xue
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Li Sun
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Yankun Yang
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Xiuxia Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Ye Li
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Zhonghu Bai
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Tian-Wei Tan
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
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Rautela A, Kumar S. Engineering plant family TPS into cyanobacterial host for terpenoids production. PLANT CELL REPORTS 2022; 41:1791-1803. [PMID: 35789422 PMCID: PMC9253243 DOI: 10.1007/s00299-022-02892-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 06/05/2022] [Indexed: 05/03/2023]
Abstract
Terpenoids are synthesized naturally by plants as secondary metabolites, and are diverse and complex in structure with multiple applications in bioenergy, food, cosmetics, and medicine. This makes the production of terpenoids such as isoprene, β-phellandrene, farnesene, amorphadiene, and squalene valuable, owing to which their industrial demand cannot be fulfilled exclusively by plant sources. They are synthesized via the Methylerythritol phosphate pathway (MEP) and the Mevalonate pathway (MVA), both existing in plants. The advent of genetic engineering and the latest accomplishments in synthetic biology and metabolic engineering allow microbial synthesis of terpenoids. Cyanobacteria manifest to be the promising hosts for this, utilizing sunlight and CO2. Cyanobacteria possess MEP pathway to generate precursors for terpenoid synthesis. The terpenoid synthesis can be amplified by overexpressing the MEP pathway and engineering MVA pathway genes. According to the desired terpenoid, terpene synthases unique to the plant kingdom must be incorporated in cyanobacteria. Engineering an organism to be used as a cell factory comes with drawbacks such as hampered cell growth and disturbance in metabolic flux. This review set forth a comparison between MEP and MVA pathways, strategies to overexpress these pathways with their challenges.
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Affiliation(s)
- Akhil Rautela
- School of Biochemical Engineering, IIT (BHU), Varanasi, 221005, Uttar Pradesh, India
| | - Sanjay Kumar
- School of Biochemical Engineering, IIT (BHU), Varanasi, 221005, Uttar Pradesh, India.
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6
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Isar J, Jain D, Joshi H, Dhoot S, Rangaswamy V. MICROBIAL isoprene production: an overview. World J Microbiol Biotechnol 2022; 38:122. [PMID: 35637362 DOI: 10.1007/s11274-022-03306-4] [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: 03/16/2022] [Accepted: 05/09/2022] [Indexed: 11/28/2022]
Abstract
Isoprene, a volatile C5 hydrocarbon, is a precursor of synthetic rubber and an important building block for a variety of natural products, solely being produced by petrochemical routes. To mitigate the ever-increasing contribution of petrochemical industry to global warming through significant carbon (CO2) evolution, bio-based process for isoprene production using microbial cell factories have been explored. Highly efficient fermentation-based processes have been studied for little over a decade now with extensive research on the rational strain development for creating robust strains for commercial isoprene production. Most of these studies involved sugars as feedstocks and using naturally occurring isoprene pathways viz., mevalonate and methyl erythritol pathway in E. coli. Recent advances, driven by efforts in reducing environmental pollution, have focused on utilization of inorganic CO2 by cyanobacteria or syngas from waste gases by acetogens for isoprene production. This review endeavors to capture the latest relevant progress made in rational strain development, metabolic engineering and synthetic biology strategies used, challenges in fermentation process development at lab and commercial scale production of isoprene along with a future perspective pertaining to this area of research.
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Affiliation(s)
- Jasmine Isar
- High Value Chemicals, Reliance Industries Limited, Reliance Corporate Park, Ghansoli, Navi Mumbai, 400701, India
| | - Dharmendra Jain
- High Value Chemicals, Reliance Industries Limited, Reliance Corporate Park, Ghansoli, Navi Mumbai, 400701, India
| | - Harshvardhan Joshi
- High Value Chemicals, Reliance Industries Limited, Reliance Corporate Park, Ghansoli, Navi Mumbai, 400701, India
| | - Shrikant Dhoot
- High Value Chemicals, Reliance Industries Limited, Reliance Corporate Park, Ghansoli, Navi Mumbai, 400701, India
| | - Vidhya Rangaswamy
- High Value Chemicals, Reliance Industries Limited, Reliance Corporate Park, Ghansoli, Navi Mumbai, 400701, India.
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Chen X, Shang C, Zhang H, Sun C, Zhang G, Liu L, Li C, Li A, Du P. Effects of Alkali Stress on the Growth and Menaquinone-7 Metabolism of Bacillus subtilis natto. Front Microbiol 2022; 13:899802. [PMID: 35572665 PMCID: PMC9096614 DOI: 10.3389/fmicb.2022.899802] [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: 03/19/2022] [Accepted: 04/08/2022] [Indexed: 11/28/2022] Open
Abstract
Menaquinone-7 (MK-7) is an important vitamin K2, synthesized from the menaquinone parent ring and seven isoprene side chains. Presently, the synthesis of MK-7 stimulated by environmental stress primarily focuses on oxygen stress, while the effect of alkali stress is rarely studied. Therefore, this study researched the effects of alkali stress on the fermentation performance and gene expression of Bacillus subtilis natto. The organism’s growth characteristics, biomass, sporogenesis, MK-7 biosynthesis, and gene expression were analyzed. After a pH 8.5 stress adaptation treatment for 0.5 h and subsequent fermentation at pH 8.5, which promoted the growth of the strain and inhibited the spore formation rate. In addition, biomass was significantly increased (P < 0.05). The conversion rate of glycerol to MK-7 was 1.68 times higher than that of the control group, and the yield of MK-7 increased to 2.10 times. Transcriptomic analysis showed that the MK-7 high-yielding strain had enhanced carbon source utilization, increased glycerol and pyruvate metabolism, enhanced the Embden-Meyerhof pathway (EMP), tricarboxylic acid (TCA) circulation flux, and terpenoid biosynthesis pathway, and promoted the accumulation of acetyl-CoA, the side-chain precursor of isoprene. At the same time, the up-regulation of transketolase increased the metabolic flux of the pentose phosphate (HMP) pathway, which was conducive to the accumulation of D-erythrose 4-phosphate, the precursor of the menadione parent ring. This study’s results contribute to a better understanding of the effects of environmental stress on MK-7 fermentation by Bacillus subtilis natto and the molecular regulatory mechanism of MK-7 biosynthesis.
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Affiliation(s)
- Xiaoqian Chen
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China
| | - Chao Shang
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China
| | - Huimin Zhang
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China
| | - Cuicui Sun
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China
| | - Guofang Zhang
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China
| | - Libo Liu
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China
| | - Chun Li
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China.,Heilongjiang Green Food Science Research Institute, Harbin, China
| | - Aili Li
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China.,Heilongjiang Green Food Science Research Institute, Harbin, China
| | - Peng Du
- Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin, China
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Luo ZW, Ahn JH, Chae TU, Choi SY, Park SY, Choi Y, Kim J, Prabowo CPS, Lee JA, Yang D, Han T, Xu H, Lee SY. Metabolic Engineering of
Escherichia
coli. Metab Eng 2021. [DOI: 10.1002/9783527823468.ch11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Cheng X, Fang T, Zhao E, Zheng B, Huang B, An Y, Zhou P. Protective roles of salicylic acid in maintaining integrity and functions of photosynthetic photosystems for alfalfa (Medicago sativa L.) tolerance to aluminum toxicity. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 155:570-578. [PMID: 32846392 DOI: 10.1016/j.plaphy.2020.08.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 08/13/2020] [Accepted: 08/13/2020] [Indexed: 06/11/2023]
Abstract
Aluminum (Al) can be detrimental to plant growth in areas with Al contamination. The objective of this study was to determine whether salicylic acid (SA) can improve plant tolerance to Al stress by mitigating Al toxicity for chloroplasts and photosynthetic systems in alfalfa (Medicago sativa L.). Plants were treated with Al (100 μM) for 3 d in a hydroponic system. The content of Al increased in leaves treated with Al, resulting in damage and deformation of chloroplasts. In Al-damaged leaves, chloroplast envelopes and starch granules disappeared; the lamellae and stroma lamella were loosely arranged and indistinguishable, and the number of grana was reduced; a large number of small plastoglobules appeared. Foliar spraying of 15 μM SA reduced Al content in roots and leaves and alleviated Al damages in chloroplasts. With 15 μM SA treatments, the chloroplast shape returned to a flat ellipsoid, thylakoids were arranged closely and regularly, chloroplasts had intact starch granules, and small plastoglobules disappeared. SA-treated plants had significantly higher aboveground biomass than the untreated control exposed to Al stress. Photosynthetic index and gene expression analyses demonstrated that SA could alleviate adverse effects of Al toxicity by increasing light capture efficiency, promoting electron transport in the photosynthetic electron transport chain and thylakoid lumen deacidification, and promoting synthesis of aenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH). SA played protective roles in maintaining integrity and functions of photosystems in photosynthesis for plant tolerance to Al stress.
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Affiliation(s)
- Xiaoqing Cheng
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Tingyu Fang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Enhua Zhao
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Baogang Zheng
- Zealquest Scientific Technology Co., Ltd., Shanghai, 200062, China
| | - Bingru Huang
- Department of Plant Biology and Pathology, Rutgers, The State University of New Jersey, New Jersey, NJ, 08901, USA
| | - Yuan An
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, 201101, China.
| | - Peng Zhou
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China.
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10
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Microbial production of vitamin K2: current status and future prospects. Biotechnol Adv 2019; 39:107453. [PMID: 31629792 DOI: 10.1016/j.biotechadv.2019.107453] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 08/24/2019] [Accepted: 09/17/2019] [Indexed: 12/18/2022]
Abstract
Vitamin K2, also called menaquinone, is an essential lipid-soluble vitamin that plays a critical role in blood clotting and prevention of osteoporosis. It has become a focus of research in recent years and has been widely used in the food and pharmaceutical industries. This review will briefly introduce the functions and applications of vitamin K2 first, after which the biosynthesis pathways and enzymes will be analyzed in-depth to highlight the bottlenecks facing the microbial vitamin K2 production on the industrial scale. Then, various strategies, including strain mutagenesis and genetic modification, different cultivation modes, fermentation and separation processes, will be summarized and discussed. The future prospects and perspectives of microbial menaquinone production will also be discussed finally.
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11
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Enhanced (−)-α-Bisabolol Productivity by Efficient Conversion of Mevalonate in Escherichia coli. Catalysts 2019. [DOI: 10.3390/catal9050432] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
(−)-α-Bisabolol, a naturally occurring sesquiterpene alcohol, has been used in pharmaceuticals and cosmetics owing to its beneficial effects on inflammation and skin healing. Previously, we reported the high production of (−)-α-bisabolol by fed-batch fermentation using engineered Escherichia coli (E. coli) expressing the exogenous mevalonate (MVA) pathway genes. The productivity of (−)-α-bisabolol must be improved before industrial application. Here, we report enhancement of initial (−)-α-bisabolol productivity to 3-fold higher than that observed in our previous study. We first harnessed a farnesyl pyrophosphate (FPP)-resistant mevalonate kinase 1 (MvaK1) from an archaeon Methanosarcina mazei (M. mazei) to create a more efficient heterologous MVA pathway that produces (−)-α-bisabolol in the engineered E. coli. The resulting strain produced 1.7-fold higher (−)-α-bisabolol relative to the strain expressing a feedback-inhibitory MvaK1 from Staphylococcus aureus (S. aureus). Next, to efficiently convert accumulated MVA to (−)-α-bisabolol, we additionally overexpressed genes involved in the lower MVA mevalonate pathway in E. coli containing the entire MVA pathway genes. (−)-α-Bisabolol production increased by 1.8-fold with reduction of MVA accumulation, relative to the control strain. Finally, we optimized the fermentation conditions including inducer concentration, aeration and enzymatic cofactor. The strain was able to produce 8.5 g/L of (−)-α-bisabolol with an initial productivity of 0.12 g/L h in the optimal fed-batch fermentation. Thus, the microbial production of (−)-α-bisabolol would be an economically viable bioprocess for its industrial application.
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