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Liu C, Choi B, Efimova E, Nygård Y, Santala S. Enhanced upgrading of lignocellulosic substrates by coculture of Saccharomyces cerevisiae and Acinetobacter baylyi ADP1. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:61. [PMID: 38711153 DOI: 10.1186/s13068-024-02510-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/23/2024] [Indexed: 05/08/2024]
Abstract
BACKGROUND Lignocellulosic biomass as feedstock has a huge potential for biochemical production. Still, efficient utilization of hydrolysates derived from lignocellulose is challenged by their complex and heterogeneous composition and the presence of inhibitory compounds, such as furan aldehydes. Using microbial consortia where two specialized microbes complement each other could serve as a potential approach to improve the efficiency of lignocellulosic biomass upgrading. RESULTS This study describes the simultaneous inhibitor detoxification and production of lactic acid and wax esters from a synthetic lignocellulosic hydrolysate by a defined coculture of engineered Saccharomyces cerevisiae and Acinetobacter baylyi ADP1. A. baylyi ADP1 showed efficient bioconversion of furan aldehydes present in the hydrolysate, namely furfural and 5-hydroxymethylfurfural, and did not compete for substrates with S. cerevisiae, highlighting its potential as a coculture partner. Furthermore, the remaining carbon sources and byproducts of S. cerevisiae were directed to wax ester production by A. baylyi ADP1. The lactic acid productivity of S. cerevisiae was improved approximately 1.5-fold (to 0.41 ± 0.08 g/L/h) in the coculture with A. baylyi ADP1, compared to a monoculture of S. cerevisiae. CONCLUSION The coculture of yeast and bacterium was shown to improve the consumption of lignocellulosic substrates and the productivity of lactic acid from a synthetic lignocellulosic hydrolysate. The high detoxification capacity and the ability to produce high-value products by A. baylyi ADP1 demonstrates the strain to be a potential candidate for coculture to increase production efficiency and economics of S. cerevisiae fermentations.
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Affiliation(s)
- Changshuo Liu
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland
| | - Bohyun Choi
- Department of Life Sciences, Industrial Biotechnology, Chalmers University of Technology, Gothenburg, Sweden
| | - Elena Efimova
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland
| | - Yvonne Nygård
- Department of Life Sciences, Industrial Biotechnology, Chalmers University of Technology, Gothenburg, Sweden
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Suvi Santala
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland.
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2
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Su H, Lin J. Biosynthesis pathways of expanding carbon chains for producing advanced biofuels. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:109. [PMID: 37400889 DOI: 10.1186/s13068-023-02340-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 05/11/2023] [Indexed: 07/05/2023]
Abstract
Because the thermodynamic property is closer to gasoline, advanced biofuels (C ≥ 6) are appealing for replacing non-renewable fossil fuels using biosynthesis method that has presented a promising approach. Synthesizing advanced biofuels (C ≥ 6), in general, requires the expansion of carbon chains from three carbon atoms to more than six carbon atoms. Despite some specific biosynthesis pathways that have been developed in recent years, adequate summary is still lacking on how to obtain an effective metabolic pathway. Review of biosynthesis pathways for expanding carbon chains will be conducive to selecting, optimizing and discovering novel synthetic route to obtain new advanced biofuels. Herein, we first highlighted challenges on expanding carbon chains, followed by presentation of two biosynthesis strategies and review of three different types of biosynthesis pathways of carbon chain expansion for synthesizing advanced biofuels. Finally, we provided an outlook for the introduction of gene-editing technology in the development of new biosynthesis pathways of carbon chain expansion.
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Affiliation(s)
- Haifeng Su
- Key Laboratory of Degraded and Unused Land Consolidation Engineering, The Ministry of Natural and Resources, Xian, 710075, Shanxi, China
| | - JiaFu Lin
- Antibiotics Research and Re-Evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of Pharmacy, Chengdu University, Chengdu, 610106, China.
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3
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Valle-Rodríguez JO, Siewers V, Nielsen J, Shi S. Directed evolution of a wax ester synthase for production of fatty acid ethyl esters in Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2023; 107:2921-2932. [PMID: 36976306 DOI: 10.1007/s00253-023-12466-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 02/21/2023] [Accepted: 02/24/2023] [Indexed: 03/29/2023]
Abstract
Wax ester synthases (WSs) utilize a fatty alcohol and a fatty acyl-coenzyme A (activated fatty acid) to synthesize the corresponding wax ester. There is much interest in developing novel cell factories that can produce shorter esters, e.g., fatty acid ethyl esters (FAEEs), with properties similar to biodiesel in order to use these as transportation fuels. However, ethanol is a poor substrate for WSs, and this may limit the biosynthesis of FAEEs. Here, we implemented a random mutagenesis approach to enhance the catalytic efficiency of a WS from Marinobacter hydrocarbonoclasticus (MhWS2, encoded by the ws2 gene). Our selection system was based on FAEE formation serving as a detoxification mechanism for excessive oleate, where high WS activity was essential for a storage-lipid free yeast to survive. A random mutagenesis library of ws2 was used to transform the storage-lipid free yeast, and mutants could be selected by plating the transformants on oleate containing plates. The variants encoding WS with improved activity were sequenced, and an identified point mutation translated into the residue substitution at position A344 was discovered to substantially increase the selectivity of MhWS2 toward ethanol and other shorter alcohols. Structural modeling indicated that an A344T substitution might affect the alcohol selectivity due to change of both steric effects and polarity changes near the active site. This work not only provides a new WS variant with altered selectivity to shorter alcohols but also presents a new high-throughput selection system to isolate WSs with a desired selectivity. KEY POINTS: • The work provides WS variants with altered substrate preference for shorter alcohols • A novel method was developed for directed evolution of WS of desired selectivity.
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Affiliation(s)
| | - Verena Siewers
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden.
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 412 96, Gothenburg, Sweden.
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970, Hørsholm, Denmark.
| | - Shuobo Shi
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden.
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
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Alhawarri MB, Dianita R, Rawa MSA, Nogawa T, Wahab HA. Potential Anti-Cholinesterase Activity of Bioactive Compounds Extracted from Cassia grandis L.f. and Cassia timoriensis DC. PLANTS (BASEL, SWITZERLAND) 2023; 12:344. [PMID: 36679057 PMCID: PMC9862305 DOI: 10.3390/plants12020344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 06/17/2023]
Abstract
Acetylcholinesterase (AChE) inhibitors remain the primary therapeutic drug that can alleviate Alzheimer's disease's (AD) symptoms. Several Cassia species have been shown to exert significant anti-AChE activity, which can be an alternative remedy for AD. Cassia timoriensis and Cassia grandis are potential plants with anti-AChE activity, but their phytochemical investigation is yet to be further conducted. The aims of this study were to identify the phytoconstituents of C. timoriensis and C. grandis and evaluate their inhibitory activity against AChE and butyrylcholinesterase (BChE). Two compounds were isolated for the first time from C. timoriensis: arachidyl arachidate (1) and luteolin (2). Five compounds were identified from C. grandis: β-sitosterol (3), stigmasterol (4), cinnamic acid (5), 4-hydroxycinnamic acid (6), and hydroxymethylfurfural (7). Compound 2 showed significant inhibition towards AChE (IC50: 20.47 ± 1.10 µM) and BChE (IC50: 46.15 ± 2.20 µM), followed by 5 (IC50: 40.5 ± 1.28 and 373.1 ± 16.4 µM) and 6 (IC50: 43.4 ± 0.61 and 409.17 ± 14.80 µM) against AChE and BChE, respectively. The other compounds exhibited poor to slightly moderate AChE inhibitory activity. Molecular docking revealed that 2 showed good binding affinity towards TcAChE (PDB ID: 1W6R) and HsBChE (PDB ID: 4BDS). It formed a hydrogen bond with TYR121 at the peripheral anionic site (PAS, 2.04 Å), along with hydrophobic interactions with the anionic site and PAS (TRP84 and TYR121, respectively). Additionally, 2 formed three H-bonds with the binding site residues: one bond with catalytic triad, HIS438 at distance 2.05 Å, and the other two H-bonds with GLY115 and GLU197 at distances of 2.74 Å and 2.19 Å, respectively. The evidence of molecular interactions of 2 may justify the relevance of C. timoriensis as a cholinesterase inhibitor, having more promising activity than C. grandis.
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Affiliation(s)
- Maram B. Alhawarri
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden 11800, Malaysia
- Faculty of Pharmacy, Jadara University, Irbid 21110, Jordan
| | - Roza Dianita
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden 11800, Malaysia
| | - Mira Syahfriena Amir Rawa
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden 11800, Malaysia
- USM-RIKEN Interdisciplinary Collaboration for Advanced Sciences (URICAS), Universiti Sains Malaysia, Gelugor 11800, Malaysia
| | - Toshihiko Nogawa
- USM-RIKEN Interdisciplinary Collaboration for Advanced Sciences (URICAS), Universiti Sains Malaysia, Gelugor 11800, Malaysia
- Molecular Structure Characterization Unit, Technology Platform Division, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Saitama 351-0198, Japan
| | - Habibah A. Wahab
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden 11800, Malaysia
- USM-RIKEN Interdisciplinary Collaboration for Advanced Sciences (URICAS), Universiti Sains Malaysia, Gelugor 11800, Malaysia
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Derstine N, Galbraith D, Villar G, Amsalem E. Differential gene expression underlying the biosynthesis of Dufour's gland signals in Bombus impatiens. CURRENT RESEARCH IN INSECT SCIENCE 2023; 3:100056. [PMID: 37124651 PMCID: PMC10130613 DOI: 10.1016/j.cris.2023.100056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 03/29/2023] [Accepted: 04/04/2023] [Indexed: 05/03/2023]
Abstract
Pheromones regulating social behavior are one of the most explored phenomena in social insects. However, compound identity, biosynthesis and their genetic basis are known in only a handful of species. Here we examined the gene expression associated with pheromone biosynthesis of two main chemical classes: esters and terpenes, using the social bee Bombus impatiens. We conducted chemical and RNA-seq analyses of the Dufour's gland, an exocrine gland producing a plethora of pheromones regulating social behavior in hymenopteran species. The Dufour's gland contains mostly long-chained hydrocarbons, terpenes and esters that signal reproductive and social status in several bee species. In bumble bees, the Dufour's gland contains queen- and worker-specific esters, in addition to terpenes and terpene-esters only found in gynes and queens. These compounds are assumed to be synthesized de novo in the gland, however, their genetic basis is unknown. A whole transcriptome gene expression analysis of the gland in queens, gynes, queenless and queenright workers showed distinct transcriptomic profiles, with thousands of differentially expressed genes between the groups. Workers and queens express genes associated with key enzymes in the biosynthesis of wax esters, while queens and gynes preferentially express key genes in terpene biosynthesis. Overall, our data demonstrate gland-specific regulation of chemical signals associated with social behavior and identifies candidate genes and pathways regulating caste-specific chemical signals in social insects.
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Ye Z, Shi B, Huang Y, Ma T, Xiang Z, Hu B, Kuang Z, Huang M, Lin X, Tian Z, Deng Z, Shen K, Liu T. Revolution of vitamin E production by starting from microbial fermented farnesene to isophytol. Innovation (N Y) 2022; 3:100228. [PMID: 35373168 PMCID: PMC8968663 DOI: 10.1016/j.xinn.2022.100228] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 03/08/2022] [Indexed: 11/16/2022] Open
Abstract
Vitamin E is one of the most widely used vitamins. In the classical commercial synthesis of vitamin E (α-tocopherol), the chemical synthesis of isophytol is the key technical barrier. Here, we establish a new process for isophytol synthesis from microbial fermented farnesene. To achieve an efficient pathway for farnesene production, Saccharomyces cerevisiae was selected as the host strain. First, β-farnesene synthase genes from different sources were screened, and through protein engineering and system metabolic engineering, a high production of β-farnesene in S. cerevisiae was achieved (55.4 g/L). This farnesene can be chemically converted into isophytol in three steps with approximately 92% yield, which is economically equal to that from the best total chemical synthesis. Furthermore, we co-produced lycopene and farnesene to reduce the cost of farnesene. A factory based on this new process was successfully operated in Hubei Province, China, in 2017, with an annual output of 30,000 tons of vitamin E. This new process has completely changed the vitamin E market due to its low cost and safety. The traditional chemical synthesis of vitamin E is complex and could be explosive An innovative way to synthesize isophytol from biofermented farnesene is established This process is safer and cheaper, changing the production and marketing of vitamin E Co-production of β-farnesene and lycopene improves the competitiveness of this process
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Affiliation(s)
- Ziling Ye
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
- J1 Biotech Co., Ltd., Wuhan 430075, China
| | - Bin Shi
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
- J1 Biotech Co., Ltd., Wuhan 430075, China
| | - Yanglei Huang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Tian Ma
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Zilei Xiang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Ben Hu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Zhaolin Kuang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Man Huang
- J1 Biotech Co., Ltd., Wuhan 430075, China
| | - Xiaoying Lin
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Zhu Tian
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Zixin Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Kun Shen
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Tiangang Liu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
- Corresponding author
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7
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Zhang Y, Guo X, Yang H, Shi S. The Studies in Constructing Yeast Cell Factories for the Production of Fatty Acid Alkyl Esters. Front Bioeng Biotechnol 2022; 9:799032. [PMID: 35087801 PMCID: PMC8787340 DOI: 10.3389/fbioe.2021.799032] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 11/19/2021] [Indexed: 12/25/2022] Open
Abstract
Fatty acid alkyl esters have broad applications in biofuels, lubricant formulas, paints, coatings, and cosmetics. Traditionally, these esters are mostly produced through unsustainable and energy-intensive processes. In contrast, microbial production of esters from renewable and sustainable feedstocks may provide a promising alternative and has attracted widespread attention in recent years. At present, yeasts are used as ideal hosts for producing such esters, due to their availability for high-density fermentation, resistance to phage infection, and tolerance against toxic inhibitors. Here, we summarize recent development on the biosynthesis of alkyl esters, including fatty acid ethyl esters (FAEEs), fatty acid short-branched chain alkyl esters (FASBEs), and wax esters (WEs) by various yeast cell factories. We focus mainly on the enzyme engineering strategies of critical wax ester synthases, and the pathway engineering strategies employed for the biosynthesis of various ester products. The bottlenecks that limit productivity and their potential solutions are also discussed in this review.
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Affiliation(s)
- Yang Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China.,CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xiao Guo
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Huaiyi Yang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Shuobo Shi
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
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8
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Zhang X, Miao Q, Xu X, Ji B, Qu L, Wei Y. Developments in Fatty Acid-Derived Insect Pheromone Production Using Engineered Yeasts. Front Microbiol 2021; 12:759975. [PMID: 34858372 PMCID: PMC8632438 DOI: 10.3389/fmicb.2021.759975] [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: 09/06/2021] [Accepted: 10/26/2021] [Indexed: 11/13/2022] Open
Abstract
The use of traditional chemical insecticides for pest control often leads to environmental pollution and a decrease in biodiversity. Recently, insect sex pheromones were applied for sustainable biocontrol of pests in fields, due to their limited adverse impacts on biodiversity and food safety compared to that of other conventional insecticides. However, the structures of insect pheromones are complex, and their chemical synthesis is not commercially feasible. As yeasts have been widely used for fatty acid-derived pheromone production in the past few years, using engineered yeasts may be promising and sustainable for the low-cost production of fatty acid-derived pheromones. The primary fatty acids produced by Saccharomyces cerevisiae and other yeasts are C16 and C18, and it is also possible to rewire/reprogram the metabolic flux for other fatty acids or fatty acid derivatives. This review summarizes the fatty acid biosynthetic pathway in S. cerevisiae and recent progress in yeast engineering in terms of metabolic engineering and synthetic biology strategies to produce insect pheromones. In the future, insect pheromones produced by yeasts might provide an eco-friendly pest control method in agricultural fields.
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Affiliation(s)
- Xiaoling Zhang
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
- Laboratory of Synthetic Biology, Zhengzhou University, Zhengzhou, China
| | - Qin Miao
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
- Laboratory of Synthetic Biology, Zhengzhou University, Zhengzhou, China
| | - Xia Xu
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Boyang Ji
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Lingbo Qu
- Laboratory of Synthetic Biology, Zhengzhou University, Zhengzhou, China
- College of Chemistry, Zhengzhou University, Zhengzhou, China
| | - Yongjun Wei
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
- Laboratory of Synthetic Biology, Zhengzhou University, Zhengzhou, China
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9
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Soong YHV, Zhao L, Liu N, Yu P, Lopez C, Olson A, Wong HW, Shao Z, Xie D. Microbial synthesis of wax esters. Metab Eng 2021; 67:428-442. [PMID: 34391890 DOI: 10.1016/j.ymben.2021.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/27/2021] [Accepted: 08/10/2021] [Indexed: 01/10/2023]
Abstract
Microbial synthesis of wax esters (WE) from low-cost renewable and sustainable feedstocks is a promising path to achieve cost-effectiveness in biomanufacturing. WE are industrially high-value molecules, which are widely used for applications in chemical, pharmaceutical, and food industries. Since the natural WE resources are limited, the WE production mostly rely on chemical synthesis from rather expensive starting materials, and therefore solution are sought from development of efficient microbial cell factories. Here we report to engineer the yeast Yarrowia lipolytica and bacterium Escherichia coli to produce WE at the highest level up to date. First, the key genes encoding fatty acyl-CoA reductases and wax ester synthase from different sources were investigated, and the expression system for two different Y. lipolytica hosts were compared and optimized for enhanced WE production and the strain stability. To improve the metabolic pathway efficiency, different carbon sources including glucose, free fatty acid, soybean oil, and waste cooking oil (WCO) were compared, and the corresponding pathway engineering strategies were optimized. It was found that using a lipid substrate such as WCO to replace glucose led to a 60-fold increase in WE production. The engineered yeast was able to produce 7.6 g/L WE with a yield of 0.31 (g/g) from WCO within 120 h and the produced WE contributed to 57% of the yeast DCW. After that, E. coli BL21(DE3), with a faster growth rate than the yeast, was engineered to significantly improve the WE production rate. Optimization of the expression system and the substrate feeding strategies led to production of 3.7-4.0 g/L WE within 40 h in a 1-L bioreactor. The predominant intracellular WE produced by both Y. lipolytica and E. coli in the presence of hydrophobic substrates as sole carbon sources were C36, C34 and C32, in an order of decreasing abundance and with a large proportion being unsaturated. This work paved the way for the biomanufacturing of WE at a large scale.
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Affiliation(s)
- Ya-Hue Valerie Soong
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Le Zhao
- Department of Chemical and Biological Engineering, NSF Engineering Research Center for Biorenewable Chemicals, Iowa State University, Ames, IA, 50011, USA
| | - Na Liu
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Peng Yu
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Carmen Lopez
- Department of Chemical and Biological Engineering, NSF Engineering Research Center for Biorenewable Chemicals, Iowa State University, Ames, IA, 50011, USA
| | - Andrew Olson
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Hsi-Wu Wong
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA
| | - Zengyi Shao
- Department of Chemical and Biological Engineering, NSF Engineering Research Center for Biorenewable Chemicals, Iowa State University, Ames, IA, 50011, USA.
| | - Dongming Xie
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA.
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10
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The impact of transcription factors Znf1, Sip4, Adr1, Tup1, and Hap4 on xylose alcoholic fermentation in the engineered yeast Saccharomyces cerevisiae. Antonie van Leeuwenhoek 2021; 114:1373-1385. [PMID: 34170419 DOI: 10.1007/s10482-021-01607-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 06/18/2021] [Indexed: 01/14/2023]
Abstract
Lignocellulosic biomass is an attractive sustainable platform for fuel ethanol production. Xylose is a second after glucose most abounded sugar in lignocellulosic hydrolysates. Effective conversion of xylose to ethanol is one of key prerequisite for the development of an efficient conversion of biomass to ethanol. Engineered Saccharomyces cerevisiae strains are able to xylose fermentation. However, the yield and productivities of xylose fermentation remains lower in comparison with glucose fermentation. In this work, we studied impact of transcription factors Znf1, Sip4, Adr1, Tup1, and Hap4 on xylose catabolism. We have isolated znf1Δ, adr1Δ, tup1Δ and hap4Δ mutants, and strains overexpressing SIP4, ADR1 and HAP4 genes on the background of xylose-fermenting strain of S. cerevisiae aiming to explore involvement of these transcription factors in regulation of xylose growth and fermentation. It was shown that hap4Δ reveal 1.8-fold increase of ethanol production from xylose as compared to that of parental strain. The hap4Δ mutant accumulates 10.38 g l-1 of ethanol with an overall ethanol yield reaching 0.41 g g-1 of consumed xylose. While the other constructed strains revealed a decrease in ethanol production from this pentose.
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Szczepańska P, Hapeta P, Lazar Z. Advances in production of high-value lipids by oleaginous yeasts. Crit Rev Biotechnol 2021; 42:1-22. [PMID: 34000935 DOI: 10.1080/07388551.2021.1922353] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The global market for high-value fatty acids production, mainly omega-3/6, hydroxy fatty-acids, waxes and their derivatives, has seen strong development in the last decade. The reason for this growth was the increasing utilization of these lipids as significant ingredients for cosmetics, food and the oleochemical industries. The large demand for these compounds resulted in a greater scientific interest in research focused on alternative sources of oil production - among which microorganisms attracted the most attention. Microbial oil production offers the possibility to engineer the pathways and store lipids enriched with the desired fatty acids. Moreover, costly chemical steps are avoided and direct commercial use of these fatty acids is available. Among all microorganisms, the oleaginous yeasts have become the most promising hosts for lipid production - their efficient lipogenesis, ability to use various (often highly affordable) carbon sources, feasible large-scale cultivations and wide range of available genetic engineering tools turns them into powerful micro-factories. This review is an in-depth description of the recent developments in the engineering of the lipid biosynthetic pathway with oleaginous yeasts. The different classes of valuable lipid compounds with their derivatives are described and their importance for human health and industry is presented. The emphasis is also placed on the optimization of culture conditions in order to improve the yield and titer of these valuable compounds. Furthermore, the important economic aspects of the current microbial oil production are discussed.
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Affiliation(s)
- Patrycja Szczepańska
- Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
| | - Piotr Hapeta
- Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
| | - Zbigniew Lazar
- Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
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12
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Ishchuk OP, Frost AT, Muñiz-Paredes F, Matsumoto S, Laforge N, Eriksson NL, Martínez JL, Petranovic D. Improved production of human hemoglobin in yeast by engineering hemoglobin degradation. Metab Eng 2021; 66:259-267. [PMID: 33984513 DOI: 10.1016/j.ymben.2021.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/09/2021] [Accepted: 05/04/2021] [Indexed: 12/23/2022]
Abstract
With the increasing demand for blood transfusions, the production of human hemoglobin (Hb) from sustainable sources is increasingly studied. Microbial production is an attractive option, as it may provide a cheap, safe, and reliable source of this protein. To increase the production of human hemoglobin by the yeast Saccharomyces cerevisiae, the degradation of Hb was reduced through several approaches. The deletion of the genes HMX1 (encoding heme oxygenase), VPS10 (encoding receptor for vacuolar proteases), PEP4 (encoding vacuolar proteinase A), ROX1 (encoding heme-dependent repressor of hypoxic genes) and the overexpression of the HEM3 (encoding porphobilinogen deaminase) and the AHSP (encoding human alpha-hemoglobin-stabilizing protein) genes - these changes reduced heme and Hb degradation and improved heme and Hb production. The reduced hemoglobin degradation was validated by a bilirubin biosensor. During glucose fermentation, the engineered strains produced 18% of intracellular Hb relative to the total yeast protein, which is the highest production of human hemoglobin reported in yeast. This increased hemoglobin production was accompanied with an increased oxygen consumption rate and an increased glycerol yield, which (we speculate) is the yeast's response to rebalance its NADH levels under conditions of oxygen limitation and increased protein-production.
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Affiliation(s)
- Olena P Ishchuk
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden.
| | - August T Frost
- Department of Biotechnology and Biomedicine, Section for Synthetic Biology, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Facundo Muñiz-Paredes
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Saki Matsumoto
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Nathalie Laforge
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Nélida Leiva Eriksson
- Department of Chemistry, Division of Biotechnology, Lund University, 221 00, Lund, Sweden
| | - José L Martínez
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden; Department of Biotechnology and Biomedicine, Section for Synthetic Biology, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Dina Petranovic
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden; Novo Nordisk Foundation Centre for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden.
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13
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Liu Y, Benitez MG, Chen J, Harrison E, Khusnutdinova AN, Mahadevan R. Opportunities and Challenges for Microbial Synthesis of Fatty Acid-Derived Chemicals (FACs). Front Bioeng Biotechnol 2021; 9:613322. [PMID: 33575251 PMCID: PMC7870715 DOI: 10.3389/fbioe.2021.613322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 01/04/2021] [Indexed: 11/13/2022] Open
Abstract
Global warming and uneven distribution of fossil fuels worldwide concerns have spurred the development of alternative, renewable, sustainable, and environmentally friendly resources. From an engineering perspective, biosynthesis of fatty acid-derived chemicals (FACs) is an attractive and promising solution to produce chemicals from abundant renewable feedstocks and carbon dioxide in microbial chassis. However, several factors limit the viability of this process. This review first summarizes the types of FACs and their widely applications. Next, we take a deep look into the microbial platform to produce FACs, give an outlook for the platform development. Then we discuss the bottlenecks in metabolic pathways and supply possible solutions correspondingly. Finally, we highlight the most recent advances in the fast-growing model-based strain design for FACs biosynthesis.
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Affiliation(s)
- Yilan Liu
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Mauricio Garcia Benitez
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Jinjin Chen
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Emma Harrison
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Anna N. Khusnutdinova
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Radhakrishnan Mahadevan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
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14
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Kawiński A, Miklaszewska M, Stelter S, Głąb B, Banaś A. Lipases of germinating jojoba seeds efficiently hydrolyze triacylglycerols and wax esters and display wax ester-synthesizing activity. BMC PLANT BIOLOGY 2021; 21:50. [PMID: 33468064 PMCID: PMC7814598 DOI: 10.1186/s12870-020-02823-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 12/30/2020] [Indexed: 05/24/2023]
Abstract
BACKGROUND Simmondsia chinensis (jojoba) is the only plant known to store wax esters instead of triacylglycerols in its seeds. Wax esters are composed of very-long-chain monounsaturated fatty acids and fatty alcohols and constitute up to 60% of the jojoba seed weight. During jojoba germination, the first step of wax ester mobilization is catalyzed by lipases. To date, none of the jojoba lipase-encoding genes have been cloned and characterized. In this study, we monitored mobilization of storage reserves during germination of jojoba seeds and performed detailed characterization of the jojoba lipases using microsomal fractions isolated from germinating seeds. RESULTS During 26 days of germination, we observed a 60-70% decrease in wax ester content in the seeds, which was accompanied by the reduction of oleosin amounts and increase in glucose content. The activity of jojoba lipases in the seed microsomal fractions increased in the first 50 days of germination. The enzymes showed higher activity towards triacylglycerols than towards wax esters. The maximum lipase activity was observed at 60 °C and pH around 7 for triacylglycerols and 6.5-8 for wax esters. The enzyme efficiently hydrolyzed various wax esters containing saturated and unsaturated acyl and alcohol moieties. We also demonstrated that jojoba lipases possess wax ester-synthesizing activity when free fatty alcohols and different acyl donors, including triacylglycerols and free fatty acids, are used as substrates. For esterification reactions, the enzyme utilized both saturated and unsaturated fatty alcohols, with the preference towards long chain and very long chain compounds. CONCLUSIONS In in vitro assays, jojoba lipases catalyzed hydrolysis of triacylglycerols and different wax esters in a broad range of temperatures. In addition, the enzymes had the ability to synthesize wax esters in the backward reaction. Our data suggest that jojoba lipases may be more similar to other plant lipases than previously assumed.
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Affiliation(s)
- Adam Kawiński
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdańsk, Poland
| | - Magdalena Miklaszewska
- Department of Plant Physiology and Biotechnology, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland.
| | - Szymon Stelter
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdańsk, Poland
| | - Bartosz Głąb
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdańsk, Poland
| | - Antoni Banaś
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdańsk, Poland
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15
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Park YK, Nicaud JM. Metabolic Engineering for Unusual Lipid Production in Yarrowia lipolytica. Microorganisms 2020; 8:E1937. [PMID: 33291339 PMCID: PMC7762315 DOI: 10.3390/microorganisms8121937] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 12/15/2022] Open
Abstract
Using microorganisms as lipid-production factories holds promise as an alternative method for generating petroleum-based chemicals. The non-conventional yeast Yarrowia lipolytica is an excellent microbial chassis; for example, it can accumulate high levels of lipids and use a broad range of substrates. Furthermore, it is a species for which an array of efficient genetic engineering tools is available. To date, extensive work has been done to metabolically engineer Y. lipolytica to produce usual and unusual lipids. Unusual lipids are scarce in nature but have several useful applications. As a result, they are increasingly becoming the targets of metabolic engineering. Unusual lipids have distinct structures; they can be generated by engineering endogenous lipid synthesis or by introducing heterologous enzymes to alter the functional groups of fatty acids. In this review, we describe current metabolic engineering strategies for improving lipid production and highlight recent researches on unusual lipid production in Y. lipolytica.
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Affiliation(s)
- Young-Kyoung Park
- Micalis Institute, AgroParisTech, INRAE, Université Paris-Saclay, 78352 Jouy-en-Josas, France;
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16
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Wang M, Wei Y, Ji B, Nielsen J. Advances in Metabolic Engineering of Saccharomyces cerevisiae for Cocoa Butter Equivalent Production. Front Bioeng Biotechnol 2020; 8:594081. [PMID: 33178680 PMCID: PMC7594527 DOI: 10.3389/fbioe.2020.594081] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 09/21/2020] [Indexed: 11/30/2022] Open
Abstract
Cocoa butter is extracted from cocoa beans, and it is mainly used as the raw material for the production of chocolate and cosmetics. Increased demands and insufficient cocoa plants led to a shortage of cocoa butter supply, and there is therefore much interesting in finding an alternative cocoa butter supply. However, the most valuable component of cocoa butter is rarely available in other vegetable oils. Saccharomyces cerevisiae is an important industrial host for production of chemicals, enzyme and pharmaceuticals. Advances in synthetical biology and metabolic engineering had enabled high-level of triacylglycerols (TAG) production in yeast, which provided possible solutions for cocoa butter equivalents (CBEs) production. Diverse engineering strategies focused on the fatty acid-producing pathway had been applied in S. cerevisiae, and the key enzymes determining the TAG structure were considered as the main engineering targets. Recent development in phytomics and multi-omics technologies provided clues to identify potential targeted enzymes, which are responsible for CBE production. In this review, we have summarized recent progress in identification of the key plant enzymes for CBE production, and discussed recent and future metabolic engineering and synthetic biology strategies for increased CBE production in S. cerevisiae.
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Affiliation(s)
- Mengge Wang
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Yongjun Wei
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Boyang Ji
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
- BioInnovation Institute, Copenhagen, Denmark
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17
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Dzanaeva LS, Ruchala J, Sibirny AA, Dmytruk KV. The Impact of Transcriptional Factors Znf1 and Sip4 on Xylose Alcoholic Fermentation in Recombinant Strains of Yeast Saccharomyces Cerevisiae. CYTOL GENET+ 2020. [DOI: 10.3103/s0095452720050035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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18
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Gao Q, Yang JL, Zhao XR, Liu SC, Liu ZJ, Wei LJ, Hua Q. Yarrowia lipolytica as a Metabolic Engineering Platform for the Production of Very-Long-Chain Wax Esters. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:10730-10740. [PMID: 32896122 DOI: 10.1021/acs.jafc.0c04393] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The oleaginous yeast Yarrowia lipolytica is an attractive cell factory platform strain and can be used for sustainable production of high-value oleochemical products. Wax esters (WEs) have a good lubricating property and are usually used as a base for the production of advanced lubricants and emollient oils. In this study, we reported the metabolic engineering of Y. lipolytica to heterologously biosynthesize high-content very-long-chain fatty acids (VLCFAs) and fatty alcohols and efficiently esterify them to obtain very-long-chain WEs. Co-expression of fatty acid elongases from different sources in Y. lipolytica could yield VLCFAs with carbon chain lengths up to 24. Combining with optimization of the central metabolic modules could further enhance the biosynthesis of VLCFAs. Furthermore, through the screening of heterologous fatty acyl reductases (FARs), we enabled high-level production of fatty alcohols. Genomic integration and heterologous expression of wax synthase (WS) and FAR in a VLCFA-producing Y. lipolytica strain yielded 95-650 mg/L WEs with carbon chain lengths from 32 to 44. Scaled-up fermentation in 5 L laboratory bioreactors significantly increased the production of WEs to 2.0 g/L, the highest content so far in yeasts. This study contributes to the further efficient biosynthesis of VLCFAs and their derivatives.
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Affiliation(s)
- Qi Gao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Jing-Lin Yang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Xin-Ru Zhao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Shun-Cheng Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Zhi-Jie Liu
- Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Key Laboratory of Industrial Microbiology, Hubei Collaborative Innovation Center of Industrial Fermentation, Hubei University of Technology, Wuhan 430068, P. R. China
| | - Liu-Jing Wei
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Qiang Hua
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai 200237, P. R. China
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19
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Shalini T, Martin A. Identification, isolation, and heterologous expression of Sunflower wax synthase for the synthesis of tailored wax esters. J Food Biochem 2020; 44:e13433. [PMID: 33090542 DOI: 10.1111/jfbc.13433] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 07/15/2020] [Accepted: 07/20/2020] [Indexed: 12/01/2022]
Abstract
Wax esters (WE) are neutral lipids formed by condensation of fatty alcohol with fatty acyl-CoA by wax synthases. They serve as carbon and energy reserves and are potential substrates for various commercial applications. Sunflower (Helianthus annuus) an edible oil seed is a source of WE, however, the gene responsible for WE formation has hitherto remained unidentified. Using an in silico approach we identified, isolated putative Sunflower wax synthase (HaWS) gene and investigated it's potential for WE production in yeast. Heterologous expression of HaWS in Saccharomyces cerevisiae H1246 exhibited 57 kDa protein which was confirmed by immunoblotting. Recombinant yeast expressing HaWS were fed with combinations of C16, C18 fatty alcohols with 16:0, 18:0 fatty acyl CoA's as potential substrates to validate WE formation in vivo. The yeast cells accumulated C-32 to C-36 WE. Our study reveals identification, isolation, and heterologous functional expression of WS gene from Sunflower for the first time. PRACTICAL APPLICATIONS: Wax synthases (WSs) are critical enzymes for wax ester (WE) biosynthesis. WEs are high value products having several industrial applications. WE serve as substrates for lubricants, food coatings, cosmetics, and pharmaceuticals. There is a demand for alternate renewable resource of WEs. In this study, we have successfully isolated a putative wax synthase gene from Sunflower and submitted its sequence data to the GenBank (Accession number MH460820). Conserved sequence search analysis showed presence of condensation superfamily motif‒HHXXXDG, critical for WE biosynthesis. Heterologous expression of HaWS in yeast revealed synthesis of C-32 to C-36 WE. Our study demonstrates the efficacy of HaWS to accumulate specific WE of desired lengths in yeast, and thus represents an alternate source of WE for commercial applications and for biotechnological production of tailored WE in eukaryotic expression systems.
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Affiliation(s)
- Theresa Shalini
- Department of Food Safety and Analytical Quality Control Laboratory, Council of Scientific and Industrial Research, Central Food Technological Research Institute, Mysore, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Asha Martin
- Department of Food Safety and Analytical Quality Control Laboratory, Council of Scientific and Industrial Research, Central Food Technological Research Institute, Mysore, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
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20
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Dzanaeva L, Kruk B, Ruchala J, Nielsen J, Sibirny A, Dmytruk K. The role of peroxisomes in xylose alcoholic fermentation in the engineered
Saccharomyces cerevisiae. Cell Biol Int 2020; 44:1606-1615. [DOI: 10.1002/cbin.11353] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 02/02/2020] [Accepted: 03/19/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Ljubov Dzanaeva
- Department of Molecular Genetics and Biotechnology, Institute of Cell BiologyNAS of UkraineLviv Ukraine
| | - Barbara Kruk
- Department of Biotechnology and MicrobiologyUniversity of RzeszowRzeszow Poland
| | - Justyna Ruchala
- Department of Biotechnology and MicrobiologyUniversity of RzeszowRzeszow Poland
| | - Jens Nielsen
- Department of Biology and Biological EngineeringChalmers University of TechnologyGothenburg Sweden
| | - Andriy Sibirny
- Department of Molecular Genetics and Biotechnology, Institute of Cell BiologyNAS of UkraineLviv Ukraine
- Department of Biotechnology and MicrobiologyUniversity of RzeszowRzeszow Poland
| | - Kostyantyn Dmytruk
- Department of Molecular Genetics and Biotechnology, Institute of Cell BiologyNAS of UkraineLviv Ukraine
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21
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Mangayil R, Efimova E, Konttinen J, Santala V. Co-production of 1,3 propanediol and long-chain alkyl esters from crude glycerol. N Biotechnol 2019; 53:81-89. [DOI: 10.1016/j.nbt.2019.07.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 06/24/2019] [Accepted: 07/10/2019] [Indexed: 10/26/2022]
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22
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Wenning L, Ejsing CS, David F, Sprenger RR, Nielsen J, Siewers V. Increasing jojoba-like wax ester production in Saccharomyces cerevisiae by enhancing very long-chain, monounsaturated fatty acid synthesis. Microb Cell Fact 2019; 18:49. [PMID: 30857535 PMCID: PMC6410506 DOI: 10.1186/s12934-019-1098-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 02/28/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Fatty acids (FAs) with a chain length of more than 18 carbon atoms (> C18) are interesting for the production of specialty compounds derived from these FAs. These compounds include free FAs, like erucic acid (C22:1-Δ13), primary fatty alcohols (FOHs), like docosanol (C22:0-FOH), as well as jojoba-like wax esters (WEs) (C38-WE to C44-WE), which are esters of (very) long-chain FAs and (very) long-chain FOHs. In particular, FAs, FOHs and WEs are used in the production of chemicals, pharmaceuticals and cosmetic products. Jojoba seed oil is highly enriched in diunsaturated WEs with over 70 mol% being composed of C18:1-C24:1 monounsaturated FOH and monounsaturated FA moieties. In this study, we aim for the production of jojoba-like WEs in the yeast Saccharomyces cerevisiae by increasing the amount of very long-chain, monounsaturated FAs and simultaneously expressing enzymes required for WE synthesis. RESULTS We show that the combined expression of a plant-derived fatty acid elongase (FAE/KCS) from Crambe abyssinica (CaKCS) together with the yeast intrinsic fatty acid desaturase (FAD) Ole1p leads to an increase in C20:1 and C22:1 FAs in S. cerevisiae. We also demonstrate that the best enzyme candidate for C24:1 FA production in S. cerevisiae is a FAE derived from Lunaria annua (LaKCS). The combined overexpression of CaKCS and Ole1p together with a fatty acyl reductase (FAR/FAldhR) from Marinobacter aquaeolei VT8 (MaFAldhR) and a wax synthase (WS) from Simmondsia chinensis (SciWS) in a S. cerevisiae strain, overexpressing a range of other enzymes involved in FA synthesis and elongation, leads to a yeast strain capable of producing high amounts of monounsaturated FOHs (up to C22:1-FOH) as well as diunsaturated WEs (up to C46:2-WE). CONCLUSIONS Changing the FA profile of the yeast S. cerevisiae towards very long-chain monounsaturated FAs is possible by combined overexpression of endogenous and heterologous enzymes derived from various sources (e.g. a marine copepod or plants). This strategy was used to produce jojoba-like WEs in S. cerevisiae and can potentially be extended towards other commercially interesting products derived from very long-chain FAs.
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Affiliation(s)
- Leonie Wenning
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden
| | - Christer S Ejsing
- Department of Biochemistry and Molecular Biology, VILLUM Center for Bioanalytical Sciences, University of Southern Denmark, 5230, Odense, Denmark
| | - Florian David
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden.,Biopetrolia AB, Kemivägen 10, 412 96, Gothenburg, Sweden
| | - Richard R Sprenger
- Department of Biochemistry and Molecular Biology, VILLUM Center for Bioanalytical Sciences, University of Southern Denmark, 5230, Odense, Denmark
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, 2800, Kgs. Lyngby, Denmark
| | - Verena Siewers
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden. .,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden.
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23
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Santala S, Efimova E, Santala V. Dynamic decoupling of biomass and wax ester biosynthesis in Acinetobacter baylyi by an autonomously regulated switch. Metab Eng Commun 2018; 7:e00078. [PMID: 30271720 PMCID: PMC6158957 DOI: 10.1016/j.mec.2018.e00078] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 09/13/2018] [Accepted: 09/16/2018] [Indexed: 01/09/2023] Open
Abstract
For improving the microbial production of fuels and chemicals, gene knock-outs and overexpression are routinely applied to intensify the carbon flow from substrate to product. However, their possibilities in dynamic control of the flux between the biomass and product synthesis are limited, whereas dynamic metabolic switches can be used for optimizing the distribution of carbon and resources. The production of single cell oils is especially challenging, as the synthesis is strictly regulated, competes directly with biomass, and requires defined conditions, such as nitrogen limitation. Here, we engineered a metabolic switch for redirecting carbon flow from biomass to wax ester production in Acinetobacter baylyi ADP1 using acetate as a carbon source. Isocitrate lyase, an essential enzyme for growth on acetate, was expressed under an arabinose inducible promoter. The autonomous downregulation of the expression is based on the gradual oxidation of the arabinose inducer by a glucose dehydrogenase gcd. The depletion of the inducer, occurring simultaneously to acetate consumption, switches the cells from a biomass mode to a lipid synthesis mode, enabling the efficient channelling of carbon to wax esters in a simple batch culture. In the engineered strain, the yield and titer of wax esters were improved by 3.8 and 3.1 folds, respectively, over the control strain. In addition, the engineered strain accumulated wax esters 19% of cell dry weight, being the highest reported among microbes. The study provides important insights into the dynamic engineering of the biomass-dependent synthesis pathways for the improved production of biocompounds from low-cost and sustainable substrates. Efficient conversion of acetate to storage lipids (wax ester) is demonstrated. AraC-pBAD promoter coupled with glucose dehydrogenase was used as a dynamic switch. The autonomous switch allowed dynamic shift from biomass to lipid synthesis mode. Wax ester yield and titer were improved by 3–4 folds over the wild type strain. The highest amount of wax esters produced in microbes, 19% of CDW, was achieved.
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Affiliation(s)
- Suvi Santala
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, FI-33720, Tampere, Finland
| | - Elena Efimova
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, FI-33720, Tampere, Finland
| | - Ville Santala
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, FI-33720, Tampere, Finland
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24
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Musiol-Kroll EM, Wohlleben W. Acyltransferases as Tools for Polyketide Synthase Engineering. Antibiotics (Basel) 2018; 7:antibiotics7030062. [PMID: 30022008 PMCID: PMC6164871 DOI: 10.3390/antibiotics7030062] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 07/14/2018] [Accepted: 07/16/2018] [Indexed: 12/16/2022] Open
Abstract
Polyketides belong to the most valuable natural products, including diverse bioactive compounds, such as antibiotics, anticancer drugs, antifungal agents, immunosuppressants and others. Their structures are assembled by polyketide synthases (PKSs). Modular PKSs are composed of modules, which involve sets of domains catalysing the stepwise polyketide biosynthesis. The acyltransferase (AT) domains and their “partners”, the acyl carrier proteins (ACPs), thereby play an essential role. The AT loads the building blocks onto the “substrate acceptor”, the ACP. Thus, the AT dictates which building blocks are incorporated into the polyketide structure. The precursor- and occasionally the ACP-specificity of the ATs differ across the polyketide pathways and therefore, the ATs contribute to the structural diversity within this group of complex natural products. Those features make the AT enzymes one of the most promising tools for manipulation of polyketide assembly lines and generation of new polyketide compounds. However, the AT-based PKS engineering is still not straightforward and thus, rational design of functional PKSs requires detailed understanding of the complex machineries. This review summarizes the attempts of PKS engineering by exploiting the AT attributes for the modification of polyketide structures. The article includes 253 references and covers the most relevant literature published until May 2018.
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Affiliation(s)
- Ewa Maria Musiol-Kroll
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
| | - Wolfgang Wohlleben
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
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Salmela M, Lehtinen T, Efimova E, Santala S, Mangayil R. Metabolic pairing of aerobic and anaerobic production in a one-pot batch cultivation. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:187. [PMID: 29988745 PMCID: PMC6029424 DOI: 10.1186/s13068-018-1186-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 06/25/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND The versatility of microbial metabolic pathways enables their utilization in vast number of applications. However, the electron and carbon recovery rates, essentially constrained by limitations of cell energetics, are often too low in terms of process feasibility. Cocultivation of divergent microbial species in a single process broadens the metabolic landscape, and thus, the possibilities for more complete carbon and energy utilization. RESULTS In this study, we integrated the metabolisms of two bacteria, an obligate anaerobe Clostridium butyricum and an obligate aerobe Acinetobacter baylyi ADP1. In the process, a glucose-negative mutant of A. baylyi ADP1 first deoxidized the culture allowing C. butyricum to grow and produce hydrogen from glucose. In the next phase, ADP1 produced long chain alkyl esters (wax esters) utilizing the by-products of C. butyricum, namely acetate and butyrate. The coculture produced 24.5 ± 0.8 mmol/l hydrogen (1.7 ± 0.1 mol/mol glucose) and 28 mg/l wax esters (10.8 mg/g glucose). CONCLUSIONS The cocultivation of strictly anaerobic and aerobic bacteria allowed the production of both hydrogen gas and long-chain alkyl esters in a simple one-pot batch process. The study demonstrates the potential of 'metabolic pairing' using designed microbial consortia for more optimal electron and carbon recovery.
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Affiliation(s)
- Milla Salmela
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, Tampere, Finland
| | - Tapio Lehtinen
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, Tampere, Finland
| | - Elena Efimova
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, Tampere, Finland
| | - Suvi Santala
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, Tampere, Finland
| | - Rahul Mangayil
- Laboratory of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, Tampere, Finland
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26
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Tupec M, Buček A, Valterová I, Pichová I. Biotechnological potential of insect fatty acid-modifying enzymes. ACTA ACUST UNITED AC 2018; 72:387-403. [PMID: 28742527 DOI: 10.1515/znc-2017-0031] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 07/25/2017] [Indexed: 01/26/2023]
Abstract
There are more than one million described insect species. This species richness is reflected in the diversity of insect metabolic processes. In particular, biosynthesis of secondary metabolites, such as defensive compounds and chemical signals, encompasses an extraordinarily wide range of chemicals that are generally unparalleled among natural products from other organisms. Insect genomes, transcriptomes and proteomes thus offer a valuable resource for discovery of novel enzymes with potential for biotechnological applications. Here, we focus on fatty acid (FA) metabolism-related enzymes, notably the fatty acyl desaturases and fatty acyl reductases involved in the biosynthesis of FA-derived pheromones. Research on insect pheromone-biosynthetic enzymes, which exhibit diverse enzymatic properties, has the potential to broaden the understanding of enzyme specificity determinants and contribute to engineering of enzymes with desired properties for biotechnological production of FA derivatives. Additionally, the application of such pheromone-biosynthetic enzymes represents an environmentally friendly and economic alternative to the chemical synthesis of pheromones that are used in insect pest management strategies.
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27
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Miklaszewska M, Dittrich-Domergue F, Banaś A, Domergue F. Wax synthase MhWS2 from Marinobacter hydrocarbonoclasticus: substrate specificity and biotechnological potential for wax ester production. Appl Microbiol Biotechnol 2018; 102:4063-4074. [DOI: 10.1007/s00253-018-8878-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 02/02/2018] [Accepted: 02/12/2018] [Indexed: 10/17/2022]
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28
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Papadaki A, Mallouchos A, Efthymiou MN, Gardeli C, Kopsahelis N, Aguieiras ECG, Freire DMG, Papanikolaou S, Koutinas AA. Production of wax esters via microbial oil synthesis from food industry waste and by-product streams. BIORESOURCE TECHNOLOGY 2017; 245:274-282. [PMID: 28892702 DOI: 10.1016/j.biortech.2017.08.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/01/2017] [Accepted: 08/02/2017] [Indexed: 06/07/2023]
Abstract
The production of wax esters using microbial oils was demonstrated in this study. Microbial oils produced from food waste and by-product streams by three oleaginous yeasts were converted into wax esters via enzymatic catalysis. Palm oil was initially used to evaluate the influence of temperature and enzyme activity on wax ester synthesis catalysed by Novozyme 435 and Lipozyme lipases using cetyl, oleyl and behenyl alcohols. The highest conversion yields (up to 79.6%) were achieved using 4U/g of Novozyme 435 at 70°C. Transesterification of microbial oils to behenyl and cetyl esters was achieved at conversion yields up to 87.3% and 69.1%, respectively. Novozyme 435 was efficiently reused for six and three cycles during palm esters and microbial esters synthesis, respectively. The physicochemical properties of microbial oil derived behenyl esters were comparable to natural waxes. Wax esters from microbial oils have potential applications in cosmetics, chemical and food industries.
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Affiliation(s)
- Aikaterini Papadaki
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece
| | - Athanasios Mallouchos
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece
| | - Maria-Nefeli Efthymiou
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece
| | - Chryssavgi Gardeli
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece
| | - Nikolaos Kopsahelis
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece; Department of Food Technology, Technological Educational Institute (TEI) of Ionian Islands, Argostoli 28100, Kefalonia, Greece
| | - Erika C G Aguieiras
- Biochemistry Department, Chemistry Institute, Federal University of Rio de Janeiro, Cidade Universitária, Centro de Tecnologia, Bloco A, Lab 549, Rio de Janeiro, RJ, Brazil
| | - Denise M G Freire
- Biochemistry Department, Chemistry Institute, Federal University of Rio de Janeiro, Cidade Universitária, Centro de Tecnologia, Bloco A, Lab 549, Rio de Janeiro, RJ, Brazil
| | - Seraphim Papanikolaou
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece
| | - Apostolis A Koutinas
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece.
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Engineering microbial fatty acid metabolism for biofuels and biochemicals. Curr Opin Biotechnol 2017; 50:39-46. [PMID: 29101852 DOI: 10.1016/j.copbio.2017.10.002] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 10/06/2017] [Accepted: 10/09/2017] [Indexed: 11/22/2022]
Abstract
Traditional oleochemical industry chemically processes animal fats and plant oils to produce detergents, lubricants, biodiesel, plastics, coatings, and other products. Biotechnology offers an alternative process, where the same oleochemicals can be produced from abundant biomass feedstocks using microbial catalysis. This review summarizes the recent advances in the engineering of microbial metabolism for production of fatty acid-derived products. We highlight the efforts in engineering the central carbon metabolism, redox metabolism, controlling the chain length of the products, and obtaining metabolites with different functionalities. The prospects of commercializing microbial oleochemicals are also discussed.
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Identification and Characterization of Phospholipids with Very Long Chain Fatty Acids in Brewer's Yeast. Lipids 2017; 52:1007-1017. [DOI: 10.1007/s11745-017-4294-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 09/04/2017] [Indexed: 10/18/2022]
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Fernandez-Moya R, Da Silva NA. Engineering Saccharomyces cerevisiae for high-level synthesis of fatty acids and derived products. FEMS Yeast Res 2017; 17:4111148. [DOI: 10.1093/femsyr/fox071] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 09/10/2017] [Indexed: 01/16/2023] Open
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