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Li T, Liu X, Xiang H, Zhu H, Lu X, Feng B. Two-Phase Fermentation Systems for Microbial Production of Plant-Derived Terpenes. Molecules 2024; 29:1127. [PMID: 38474639 DOI: 10.3390/molecules29051127] [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: 02/13/2024] [Revised: 02/28/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Microbial cell factories, renowned for their economic and environmental benefits, have emerged as a key trend in academic and industrial areas, particularly in the fermentation of natural compounds. Among these, plant-derived terpenes stand out as a significant class of bioactive natural products. The large-scale production of such terpenes, exemplified by artemisinic acid-a crucial precursor to artemisinin-is now feasible through microbial cell factories. In the fermentation of terpenes, two-phase fermentation technology has been widely applied due to its unique advantages. It facilitates in situ product extraction or adsorption, effectively mitigating the detrimental impact of product accumulation on microbial cells, thereby significantly bolstering the efficiency of microbial production of plant-derived terpenes. This paper reviews the latest developments in two-phase fermentation system applications, focusing on microbial fermentation of plant-derived terpenes. It also discusses the mechanisms influencing microbial biosynthesis of terpenes. Moreover, we introduce some new two-phase fermentation techniques, currently unexplored in terpene fermentation, with the aim of providing more thoughts and explorations on the future applications of two-phase fermentation technology. Lastly, we discuss several challenges in the industrial application of two-phase fermentation systems, especially in downstream processing.
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Affiliation(s)
- Tuo Li
- College of Life and Health, Dalian University, Dalian 116622, China
| | - Ximeng Liu
- College of Life and Health, Dalian University, Dalian 116622, China
| | - Haoyu Xiang
- College of Life and Health, Dalian University, Dalian 116622, China
| | - Hehua Zhu
- College of Life and Health, Dalian University, Dalian 116622, China
| | - Xuan Lu
- College of Life and Health, Dalian University, Dalian 116622, China
| | - Baomin Feng
- College of Life and Health, Dalian University, Dalian 116622, China
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Cheng T, Wang L, Sun C, Xie C. Optimizing the downstream MVA pathway using a combination optimization strategy to increase lycopene yield in Escherichia coli. Microb Cell Fact 2022; 21:121. [PMID: 35718767 PMCID: PMC9208136 DOI: 10.1186/s12934-022-01843-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 06/01/2022] [Indexed: 11/20/2022] Open
Abstract
Background Lycopene is increasing in demand due to its widespread use in the pharmaceutical and food industries. Metabolic engineering and synthetic biology technologies have been widely used to overexpress the heterologous mevalonate pathway and lycopene pathway in Escherichia coli to produce lycopene. However, due to the tedious metabolic pathways and complicated metabolic background, optimizing the lycopene synthetic pathway using reasonable design approaches becomes difficult. Results In this study, the heterologous lycopene metabolic pathway was introduced into E. coli and divided into three modules, with mevalonate and DMAPP serving as connecting nodes. The module containing the genes (MVK, PMK, MVD, IDI) of downstream MVA pathway was adjusted by altering the expression strength of the four genes using the ribosome binding sites (RBSs) library with specified strength to improve the inter-module balance. Three RBS libraries containing variably regulated MVK, PMK, MVD, and IDI were constructed based on different plasmid backbones with the variable promoter and replication origin. The RBS library was then transformed into engineered E. coli BL21(DE3) containing pCLES and pTrc-lyc to obtain a lycopene producer library and employed high-throughput screening based on lycopene color to obtain the required metabolic pathway. The shake flask culture of the selected high-yield strain resulted in a lycopene yield of 219.7 mg/g DCW, which was 4.6 times that of the reference strain. Conclusion A strain capable of producing 219.7 mg/g DCW with high lycopene metabolic flux was obtained by fine-tuning the expression of the four MVA pathway enzymes and visual selection. These results show that the strategy of optimizing the downstream MVA pathway through RBS library design can be effective, which can improve the metabolic flux and provide a reference for the synthesis of other terpenoids. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01843-z.
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Affiliation(s)
- Tao Cheng
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Zhengzhou Road, Qingdao, 266042, China. .,CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Laoshan District, Qingdao, 266101, China.
| | - Lili Wang
- Department of Pathology, the Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266000, China
| | - Chao Sun
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Zhengzhou Road, Qingdao, 266042, China.,CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Laoshan District, Qingdao, 266101, China
| | - Congxia Xie
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Zhengzhou Road, Qingdao, 266042, China.
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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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Yang Q, Zheng Z, Zhao G, Wang L, Wang H, Ding X, Jiang C, Li C, Ma G, Wang P. Engineering microbial consortia of Elizabethkingia meningoseptica and Escherichia coli strains for the biosynthesis of vitamin K2. Microb Cell Fact 2022; 21:37. [PMID: 35279147 PMCID: PMC8917678 DOI: 10.1186/s12934-022-01768-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 03/03/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
The study and application of microbial consortia are topics of interest in the fields of metabolic engineering and synthetic biology. In this study, we report the design and optimisation of Elizabethkingia meningoseptica and Escherichia coli co-culture, which bypass certain limitations found during the molecular modification of E. meningoseptica, such as resistance to many antibiotics and fewer available molecular tools.
Results
The octaprenyl pyrophosphate synthase from E. meningoseptica sp. F2 (EmOPPS) was expressed, purified, and identified in the present study. Then, owing to the low vitamin K2 production by E. coli or E. meningoseptica sp. F2 monoculture, we introduced the E. meningoseptica and E. coli co-culture strategy to improve vitamin K2 biosynthesis. We achieved production titres of 32 mg/L by introducing vitamin K2 synthesis-related genes from E. meningoseptica sp. F2 into E. coli, which were approximately three-fold more than the titre achieved with E. meningoseptica sp. F2 monoculture. This study establishes a foundation for further engineering of MK-n (n = 4, 5, 6, 7, 8) in a co-cultivation system of E. meningoseptica and E. coli. Finally, we analysed the surface morphology, esterase activity, and membrane permeability of these microbial consortia using scanning electron microscopy, confocal laser scanning microscopy, and flow cytometry, respectively. The results showed that the co-cultured bacteria were closely linked and that lipase activity and membrane permeability improved, which may be conducive to the exchange of substances between bacteria.
Conclusions
Our results demonstrated that co-culture engineering can be a useful method in the broad field of metabolic engineering of strains with restricted molecular modifications.
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Co-Production of Isoprene and Lactate by Engineered Escherichia coli in Microaerobic Conditions. Molecules 2021; 26:molecules26237173. [PMID: 34885764 PMCID: PMC8659262 DOI: 10.3390/molecules26237173] [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: 10/30/2021] [Revised: 11/23/2021] [Accepted: 11/25/2021] [Indexed: 11/21/2022] Open
Abstract
Lactate and isoprene are two common monomers for the industrial production of polyesters and synthetic rubbers. The present study tested the co-production of D-lactate and isoprene by engineered Escherichia coli in microaerobic conditions. The deletion of alcohol dehydrogenase (adhE) and acetate kinase (ackA) genes, along with the supplementation with betaine, improved the co-production of lactate and isoprene from the substrates of glucose and mevalonate. In fed-batch studies, microaerobic fermentation significantly improved the isoprene concentration in fermentation outlet gas (average 0.021 g/L), compared with fermentation under aerobic conditions (average 0.0009 g/L). The final production of D-lactate and isoprene can reach 44.0 g/L and 3.2 g/L, respectively, through fed-batch microaerobic fermentation. Our study demonstrated a dual-phase production strategy in the co-production of isoprene (gas phase) and lactate (liquid phase). The increased concentration of gas-phase isoprene could benefit the downstream process and decrease the production cost to collect and purify the bio-isoprene from the fermentation outlet gas. The proposed microaerobic process can potentially be applied in the production of other volatile bioproducts to benefit the downstream purification process.
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Zhang G, Zhang N, Yang A, Huang J, Ren X, Xian M, Zou H. Hop bitter acids: resources, biosynthesis, and applications. Appl Microbiol Biotechnol 2021; 105:4343-4356. [PMID: 34021813 DOI: 10.1007/s00253-021-11329-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/26/2021] [Accepted: 04/29/2021] [Indexed: 01/15/2023]
Abstract
Diversified members of hop bitter acids (α- and β-acids) have been found in hop (Humulus lupulus). Mixtures of hop bitter acids have been traditionally applied in brewing and food industries as bitterness flavors or food additives. Recent studies have discovered novel applications of hop bitter acids and their derivatives in medicinal and pharmaceutical fields. The increasing demands of purified hop bitter acid promoted biosynthesis efforts for the heterologous biosynthesis of objective hop bitter acids by engineered microbial factories. In this study, the updated information of hop bitter acids and their representative application in brewing, food, and medicine fields are reviewed. We also speculate future trends on the development of robust microbial cell factories and biotechnologies for the biosynthesis of hop bitter acids. KEY POINTS: • Structures and applications of hop bitter acids are summarized in this study. • Biosynthesis of hop bitter acids remains challenging. • We discuss potential strategies in the microbial production of hop bitter acids.
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Affiliation(s)
- Guoqing Zhang
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Nan Zhang
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Anran Yang
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Jingling Huang
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Xueni Ren
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Mo Xian
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Huibin Zou
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China. .,CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.
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Liu H, Cao Y, Guo J, Xu X, Long Q, Song L, Xian M. Study on the isoprene-producing co-culture system of Synechococcus elongates-Escherichia coli through omics analysis. Microb Cell Fact 2021; 20:6. [PMID: 33413404 PMCID: PMC7791884 DOI: 10.1186/s12934-020-01498-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 12/15/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The majority of microbial fermentations are currently performed in the batch or fed-batch manner with the high process complexity and huge water consumption. The continuous microbial production can contribute to the green sustainable development of the fermentation industry. The co-culture systems of photo-autotrophic and heterotrophic species can play important roles in establishing the continuous fermentation mode for the bio-based chemicals production. RESULTS In the present paper, the co-culture system of Synechococcus elongates-Escherichia coli was established and put into operation stably for isoprene production. Compared with the axenic culture, the fermentation period of time was extended from 100 to 400 h in the co-culture and the isoprene production was increased to eightfold. For in depth understanding this novel system, the differential omics profiles were analyzed. The responses of BL21(DE3) to S. elongatus PCC 7942 were triggered by the oxidative pressure through the Fenton reaction and all these changes were linked with one another at different spatial and temporal scales. The oxidative stress mitigation pathways might contribute to the long-lasting fermentation process. The performance of this co-culture system can be further improved according to the fundamental rules discovered by the omics analysis. CONCLUSIONS The isoprene-producing co-culture system of S. elongates-E. coli was established and then analyzed by the omics methods. This study on the co-culture system of the model S. elongates-E. coli is of significance to reveal the common interactions between photo-autotrophic and heterotrophic species without natural symbiotic relation, which could provide the scientific basis for rational design of microbial community.
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Affiliation(s)
- Hui Liu
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Yujin Cao
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Jing Guo
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Xin Xu
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Qi Long
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Lili Song
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Mo Xian
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
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Jia H, Chen T, Qu J, Yao M, Xiao W, Wang Y, Li C, Yuan Y. Collaborative subcellular compartmentalization to improve GPP utilization and boost sabinene accumulation in Saccharomyces cerevisiae. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Zou S, Wang Z, Zhao K, Zhang B, Niu K, Liu Z, Zheng Y. High‐level production of
d
‐pantothenic acid from glucose by fed‐batch cultivation of
Escherichia coli. Biotechnol Appl Biochem 2020; 68:1227-1235. [DOI: 10.1002/bab.2044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Shu‐Ping Zou
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of Technology Hangzhou People's Republic of China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou People's Republic of China
| | - Zhi‐Jian Wang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of Technology Hangzhou People's Republic of China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou People's Republic of China
| | - Kuo Zhao
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of Technology Hangzhou People's Republic of China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou People's Republic of China
| | - Bo Zhang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of Technology Hangzhou People's Republic of China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou People's Republic of China
| | - Kun Niu
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of Technology Hangzhou People's Republic of China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou People's Republic of China
| | - Zhi‐Qiang Liu
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of Technology Hangzhou People's Republic of China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou People's Republic of China
| | - Yu‐Guo Zheng
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of Technology Hangzhou People's Republic of China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou People's Republic of China
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Improved cis-Abienol production through increasing precursor supply in Escherichia coli. Sci Rep 2020; 10:16791. [PMID: 33033333 PMCID: PMC7545193 DOI: 10.1038/s41598-020-73934-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 09/24/2020] [Indexed: 12/16/2022] Open
Abstract
cis-Abienol, a natural diterpene-diol isolated from balsam fir (Abies balsamea), can be employed as precursors for the semi-synthesis of amber compounds, which are sustainable replacement for ambergris and widely used in the fragmented industry. This study combinatorially co-expressed geranyl diphosphate synthase, geranylgeranyl diphosphate synthase, Labda-13-en-8-ol diphosphate synthase and diterpene synthase, with the best combination achieving ~ 0.3 mg/L of cis-abienol. An additional enhancement of cis-abienol production (up to 8.6 mg/L) was achieved by introducing an exogenous mevalonate pathway which was divided into the upper pathway containing acetyl-CoA acetyltransferase/HMG-CoA reductase and HMG-CoA synthase and the lower pathway containing mevalonate kinase, phosphomevalonate kinase, pyrophosphate mevalonate decarboxylase and isopentenyl pyrophosphate isomerase. The genetically modified strain carrying chromosomal copy of low genes of the mevalonate with the trc promoter accumulated cis-abienol up to 9.2 mg/L in shake flask. Finally, cis-abienol titers of ~ 220 mg/L could be achieved directly from glucose using this de novo cis-abienol-producing E. coli in high-cell-density fermentation. This study demonstrates a microbial process to apply the E. coli cell factory in the biosynthesis of cis-abienol.
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Paper Mill Sludge as a Source of Sugars for Use in the Production of Bioethanol and Isoprene. ENERGIES 2020. [DOI: 10.3390/en13184662] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Paper mill sludge (PMS) solids are predominantly comprised of cellulosic fibers and fillers rejected during the pulping or paper making process. Most sludges are dewatered and discharged into landfills or land spread at a cost to the mill; creating large economic and environmental burdens. This lignocellulosic residual stream can be used as a source of sugars for microbial fermentation to renewable chemicals. The aim of this study was to determine the possibility of converting mill sludge to sugars and then fermentation to either isoprene or ethanol. Chemical analysis indicated that the cellulosic fiber composition between 28 to 68% and hemicellulose content ranged from 8.4 to 10.7%. Calcium carbonate concentration in the sludge ranged from 0.4 to 34%. Sludge samples were enzyme hydrolyzed to convert cellulose fibers to glucose, percent conversion ranged from 10.5 to 98%. Calcium carbonate present with the sludge resulted in low hydrolysis rates; washing of sludge with hydrochloric acid to neutralize the calcium carbonate, increased hydrolysis rates by 50 to 88%. The production of isoprene “very low” (190 to 470 nmol) because the isoprene yields were little. Using an industrial yeast strain for fermentation of the sludge sugars obtained from all sludge samples, the maximum conversion efficiency was achieved with productivity ranging from 0.18 to 1.64 g L−1 h−1. Our data demonstrates that PMS can be converted into sugars that can be fermented to renewable chemicals for industry.
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Hollywood KA, Schmidt K, Takano E, Breitling R. Metabolomics tools for the synthetic biology of natural products. Curr Opin Biotechnol 2018; 54:114-120. [DOI: 10.1016/j.copbio.2018.02.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/22/2018] [Accepted: 02/27/2018] [Indexed: 12/15/2022]
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Wilson J, Gering S, Pinard J, Lucas R, Briggs BR. Bio-production of gaseous alkenes: ethylene, isoprene, isobutene. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:234. [PMID: 30181774 PMCID: PMC6114056 DOI: 10.1186/s13068-018-1230-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 08/17/2018] [Indexed: 05/05/2023]
Abstract
To reduce emissions from petrochemical refinement, bio-production has been heralded as a way to create economically valuable compounds with fewer harmful effects. For example, gaseous alkenes are precursor molecules that can be polymerized into a variety of industrially significant compounds and have biological production pathways. Production levels, however, remain low, thus enhancing bio-production of gaseous petrochemicals for chemical precursors is critical. This review covers the metabolic pathways and production levels of the gaseous alkenes ethylene, isoprene, and isobutene. Techniques needed to drive production to higher levels are also discussed.
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Affiliation(s)
- James Wilson
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Sarah Gering
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Jessica Pinard
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Ryan Lucas
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Brandon R. Briggs
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
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Biosynthesis and production of sabinene: current state and perspectives. Appl Microbiol Biotechnol 2017; 102:1535-1544. [DOI: 10.1007/s00253-017-8695-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 12/03/2017] [Accepted: 12/04/2017] [Indexed: 01/10/2023]
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