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Huang M, Cui X, Zhang P, Jin Z, Li H, Liu J, Jiang Z. Engineered Saccharomyces cerevisiae harbors xylose isomerase and xylose transporter improves co-fermentation of xylose and glucose for ethanol production. Prep Biochem Biotechnol 2024; 54:1058-1067. [PMID: 38349751 DOI: 10.1080/10826068.2024.2315479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Saccharomyces cerevisiae cannot assimilate xylose, second to glucose derived from lignocellulosic biomass. Here, the engineered S. cerevisiae strains INVSc-XI and INVSc-XI/XT were constructed using xylA and Xltr1p to co-utilize xylose and glucose, achieving economic viability and sustainable production of fuels. The xylose utilization rate of INVSc-XI/XT was 2.3-fold higher than that of INVSc-XI, indicating that overexpressing Xltr1p could further enhance xylose utilization. In mixed sugar media, a small amount of glucose enhanced the consumption of xylose by INVSc-XI/XT. Transcriptome analysis showed that glucose increased the upregulation of acetate of coenzyme A synthetase (ACS), alcohol dehydrogenase (ADH), and transketolase (TKL) gene expression in INVSc-XI/XT, further promoting xylose utilization and ethanol yield. The highest ethanol titer of 2.91 g/L with a yield of 0.29 g/g at 96 h by INVSc-XI/XT was 56.9% and 63.0% of the theoretical ethanol yield from glucose and xylose, respectively. These results showed overexpression of xylA and Xltr1p is a promising strategy for improving xylose and glucose conversion to ethanol. Although the ability of strain INVSc-XI/XT to produce ethanol was not very satisfactory, glucose was discovered to influence xylose utilization in strain INVSc-XI/XT. Altering the glucose concentration is a promising strategy to improve the xylose and glucose co-utilization.
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Affiliation(s)
- Mengtian Huang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, P.R. China
- College of Life Science and Technology, Hubei Engineering University, Xiaogan, P.R. China
| | - Xinxin Cui
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, P.R. China
| | - Peining Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, P.R. China
| | - Zhuocheng Jin
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, P.R. China
| | - Huanan Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, P.R. China
| | - Jiashu Liu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, P.R. China
| | - Zhengbing Jiang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, P.R. China
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Yi X, Han J, Xu X, Wang Y, Zhang M, Zhu J, He Y. Taurine-mediated gene transcription and cell membrane permeability reinforced co-production of bioethanol and Monascus azaphilone pigments for a newly isolated Monascus purpureus. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:59. [PMID: 38702823 PMCID: PMC11069175 DOI: 10.1186/s13068-024-02511-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 04/26/2024] [Indexed: 05/06/2024]
Abstract
BACKGROUND Taurine, a semi-essential micronutrient, could be utilized as a sulfur source for some bacteria; however, little is known about its effect on the accumulation of fermentation products. Here, it investigated the effect of taurine on co-production of bioethanol and Monascus azaphilone pigments (MonAzPs) for a fungus. RESULTS A newly isolated fungus of 98.92% identity with Monascus purpureus co-produced 23.43 g/L bioethanol and 66.12, 78.01 and 62.37 U/mL red, yellow and orange MonAzPs for 3 d in synthetic medium (SM). Taurine enhanced bioethanol titer, ethanol productivity and ethanol yield at the maximum by 1.56, 1.58 and 1.60 times than those of the control in corn stover hydrolysates (CSH), and red, yellow and orange MonAzPs were raised by 1.24, 1.26 and 1.29 times, respectively. Taurine was consumed extremely small quantities for M. purpureus and its promotional effect was not universal for the other two biorefinery fermenting strains. Taurine intensified the gene transcription of glycolysis (glucokinase, phosphoglycerate mutase, enolase and alcohol dehydrogenase) and MonAzPs biosynthesis (serine hydrolases, C-11-ketoreductase, FAD-dependent monooxygenase, 4-O-acyltransferase, deacetylase, NAD(P)H-dependent oxidoredutase, FAD-dependent oxidoredutase, enoyl reductase and fatty acid synthase) through de novo RNA-Seq assays. Furthermore, taurine improved cell membrane permeability through changing cell membrane structure by microscopic imaging assays. CONCLUSIONS Taurine reinforced co-production of bioethanol and MonAzPs by increasing gene transcription level and cell membrane permeability for M. purpureus. This work would offer an innovative, efficient and taurine-based co-production system for mass accumulation of the value-added biofuels and biochemicals from lignocellulosic biomass.
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Affiliation(s)
- Xia Yi
- National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Institute of Urban and Rural Mining, Changzhou Key Laboratory of Biomass Green, Safe & High Value Utilization Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China.
| | - Jianqi Han
- National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Institute of Urban and Rural Mining, Changzhou Key Laboratory of Biomass Green, Safe & High Value Utilization Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China
| | - Xiaoyan Xu
- School of Pharmacy & School of Biological and Food Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China
| | - Yilong Wang
- School of Pharmacy & School of Biological and Food Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China
| | - Meng Zhang
- National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Institute of Urban and Rural Mining, Changzhou Key Laboratory of Biomass Green, Safe & High Value Utilization Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China
| | - Jie Zhu
- National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Institute of Urban and Rural Mining, Changzhou Key Laboratory of Biomass Green, Safe & High Value Utilization Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China.
| | - Yucai He
- School of Pharmacy & School of Biological and Food Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China.
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Ran Y, Yang Q, Zeng J, Li F, Cao Y, Xu Q, Qiao D, Xu H, Cao Y. Potential xylose transporters regulated by CreA improved lipid yield and furfural tolerance in oleaginous yeast Saitozyma podzolica zwy-2-3. BIORESOURCE TECHNOLOGY 2023; 386:129413. [PMID: 37390935 DOI: 10.1016/j.biortech.2023.129413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/26/2023] [Accepted: 06/27/2023] [Indexed: 07/02/2023]
Abstract
Lignocellulose's hydrolysate, a significant renewable source, contains xylose and furfural, making it challenging for industrial production of oleaginous yeast. On xylose fermentation with furfural treatment, OE::DN7263 and OE::DN7661 increased lipid yield and furfural tolerance versus WT, while, which of OE::CreA were decreased owing to CreA regulating DN7263 and DN7661 negatively. OE::CreA generated reactive oxygen species (ROS) causing oxidative damage. OE::DN7263, OE::DN7661, and ΔCreA reduced furfural via NADH; while ΔCreA produced less ROS and OE::DN7263, and OE::DN7661 scavenged ROS quickly, minimizing oxidative damage. Overall, CreA knockout increased DN7263 and DN7661 expression to facilitate xylose assimilation, enhancing NADH generation and ROS clearance. Finally, with mixed sugar fermentation, ΔCreA and OE::DN7263's biomass and lipid yield rose without furfural addition, while that of ΔCreA remained higher than WT after furfural treatment. These findings revealed how oleaginous yeast zwy-2-3 resisted furfural stress and indicated ΔCreA and OE::DN7263 might develop into robust industrial chassis strains.
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Affiliation(s)
- Yulu Ran
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China
| | - Qingzhuoma Yang
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China
| | - Jie Zeng
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China
| | - Fazhi Li
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China
| | - Yu Cao
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China
| | - Qingrui Xu
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China
| | - Dairong Qiao
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China
| | - Hui Xu
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China.
| | - Yi Cao
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, Sichuan Province 610065, PR China.
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Arhin SG, Cesaro A, Di Capua F, Esposito G. Recent progress and challenges in biotechnological valorization of lignocellulosic materials: Towards sustainable biofuels and platform chemicals synthesis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159333. [PMID: 36220479 DOI: 10.1016/j.scitotenv.2022.159333] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 10/04/2022] [Accepted: 10/05/2022] [Indexed: 06/16/2023]
Abstract
Lignocellulosic materials (LCM) have garnered attention as feedstocks for second-generation biofuels and platform chemicals. With an estimated annual production of nearly 200 billion tons, LCM represent an abundant source of clean, renewable, and sustainable carbon that can be funneled to numerous biofuels and platform chemicals by sustainable microbial bioprocessing. However, the low bioavailability of LCM due to the recalcitrant nature of plant cell components, the complexity and compositional heterogeneity of LCM monomers, and the limited metabolic flexibility of wild-type product-forming microorganisms to simultaneously utilize various LCM monomers are major roadblocks. Several innovative strategies have been proposed recently to counter these issues and expedite the widespread commercialization of biorefineries using LCM as feedstocks. Herein, we critically summarize the recent advances in the biological valorization of LCM to value-added products. The review focuses on the progress achieved in the development of strategies that boost efficiency indicators such as yield and selectivity, minimize carbon losses via integrated biorefinery concepts, facilitate carbon co-metabolism and carbon-flux redirection towards targeted products using recently engineered microorganisms, and address specific product-related challenges, to provide perspectives on future research needs and developments. The strategies and views presented here could guide future studies in developing feasible and economically sustainable LCM-based biorefineries as a crucial node in achieving carbon neutrality.
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Affiliation(s)
- Samuel Gyebi Arhin
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples, Italy.
| | - Alessandra Cesaro
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples, Italy
| | - Francesco Di Capua
- School of Engineering, University of Basilicata, via dell'Ateneo Lucano 10, 85100 Potenza, Italy
| | - Giovanni Esposito
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples, Italy
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Wang X, Yang J, Mohamed H, Shah AM, Li S, Pang S, Wu C, Xue F, Shi W, Sadaqat B, Song Y. Simultaneous overexpression of ∆6-, ∆12- and ∆9-desaturases enhanced the production of γ-linolenic acid in Mucor circinelloides WJ11. Front Microbiol 2022; 13:1078157. [PMID: 36590442 PMCID: PMC9797528 DOI: 10.3389/fmicb.2022.1078157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 11/23/2022] [Indexed: 12/16/2022] Open
Abstract
Mucor circinelloides WJ11, an oleaginous filamentous fungus, produces 36% lipid of its cell dry weight when cultured in a high C/N ratio medium, however, the yield of γ-linolenic acid (GLA) is insufficient to make it competitive with other plant sources. To increase the GLA content in M. circinelloides WJ11, this fungus was engineered by overexpression of its key genes such as Δ6-, Δ12-, and Δ9-desaturases involved in GLA production. Firstly, we tried to overexpress two Δ6-desaturase isozymes to determine which one played important role in GLA synthesis. Secondly, Δ6-and Δ12-desaturase were co-overexpressed to check whether linoleic acid (LA), the precursor for GLA synthesis, is a limiting factor or not. Moreover, we tried to explore the effects of simultaneous overexpression of Δ6-, Δ12-, and Δ9-desaturases on GLA production. Our results showed that overexpression (1 gene) of DES61 promoted higher GLA content (21% of total fatty acids) while co-overexpressing (2 genes) DES61 and DES12 and simultaneous overexpressing (3 genes) DES61, DES12, and DES91 increased the GLA production of engineered strains by 1.5 folds and 1.9 folds compared to the control strain, respectively. This study provided more insights into GLA biosynthesis in oleaginous fungi and laid a foundation for further increase in GLA production into fungus such as M. circinelloides.
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Affiliation(s)
- Xiuwen Wang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Junhuan Yang
- Department of Food Sciences, College of Food Science and Engineering, Lingnan Normal University, Zhanjiang, China
| | - Hassan Mohamed
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China,Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - Aabid Manzoor Shah
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Shaoqi Li
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Shuxian Pang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Chen Wu
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Futing Xue
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Wenyue Shi
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Beenish Sadaqat
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China,*Correspondence: Yuanda Song,
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Homologous and Heterologous Expression of Delta(12)-Desaturase in Mucor circinelloides Enhanced the Production of Linolenic Acid. Molecules 2022; 27:molecules27175511. [PMID: 36080278 PMCID: PMC9457725 DOI: 10.3390/molecules27175511] [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: 08/04/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/21/2022] Open
Abstract
Linolenic acid (LA) is gaining more interest within the scientific community. This is because it has a potential medical role in reducing the risk of inflammation, carcinogenesis, atherosclerosis and diabetes and is a valuable nutraceutical for human health. The oleaginous fungus Mucor circinelloides produces a high lipid content (36%), including valuable polyunsaturated fatty acids (PUFAs). However, the critical step in which oleic acid (OA) is converted into LA is not efficient at supplying enough substrates for PUFA synthesis. Hence, we propose a method to increase LA production based on genetic engineering. The overexpression of the Δ12-desaturase gene from M. circinelloides and Mortierella alpina increased the LA content and improved the lipid accumulation (from 14.9% to 21.6% in the Δ12-desaturase gene of the M. circinelloides overexpressing strain (Mc-D12MC) and from 14.9% to 18.7% in the Δ12-desaturase gene of M. alpina overexpressing strain (Mc-D12MA)). Additionally, the up-regulated expression levels of these genes targeted the genes involved in NADPH production, implying that the elevated Δ12-desaturase gene may function as a critical regulator of NADPH and lipid synthesis in M. circinelloides. This study provides the first evidence to support the design of metabolic engineering related to LA and PUFA production in M. circinelloides for potential industrial applications.
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Mhatre A, Shinde S, Jha AK, Rodriguez A, Wardak Z, Jansen A, Gladden JM, George A, Davis RW, Varman AM. Corynebacterium glutamicum as an Efficient Omnivorous Microbial Host for the Bioconversion of Lignocellulosic Biomass. Front Bioeng Biotechnol 2022; 10:827386. [PMID: 35433642 PMCID: PMC9011048 DOI: 10.3389/fbioe.2022.827386] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 03/03/2022] [Indexed: 01/07/2023] Open
Abstract
Corynebacterium glutamicum has been successfully employed for the industrial production of amino acids and other bioproducts, partially due to its native ability to utilize a wide range of carbon substrates. We demonstrated C. glutamicum as an efficient microbial host for utilizing diverse carbon substrates present in biomass hydrolysates, such as glucose, arabinose, and xylose, in addition to its natural ability to assimilate lignin-derived aromatics. As a case study to demonstrate its bioproduction capabilities, L-lactate was chosen as the primary fermentation end product along with acetate and succinate. C. glutamicum was found to grow well in different aromatics (benzoic acid, cinnamic acid, vanillic acid, and p-coumaric acid) up to a concentration of 40 mM. Besides, 13C-fingerprinting confirmed that carbon from aromatics enter the primary metabolism via TCA cycle confirming the presence of β-ketoadipate pathway in C. glutamicum. 13C-fingerprinting in the presence of both glucose and aromatics also revealed coumarate to be the most preferred aromatic by C. glutamicum contributing 74 and 59% of its carbon for the synthesis of glutamate and aspartate respectively. 13C-fingerprinting also confirmed the activity of ortho-cleavage pathway, anaplerotic pathway, and cataplerotic pathways. Finally, the engineered C. glutamicum strain grew well in biomass hydrolysate containing pentose and hexose sugars and produced L-lactate at a concentration of 47.9 g/L and a yield of 0.639 g/g from sugars with simultaneous utilization of aromatics. Succinate and acetate co-products were produced at concentrations of 8.9 g/L and 3.2 g/L, respectively. Our findings open the door to valorize all the major carbon components of biomass hydrolysate by using C. glutamicum as a microbial host for biomanufacturing.
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Affiliation(s)
- Apurv Mhatre
- Chemical Engineering Program, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ, United States
| | - Somnath Shinde
- Department of Bioresource and Environmental Security, Sandia National Laboratories, Livermore, CA, United States
| | - Amit Kumar Jha
- Chemical Engineering Program, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ, United States,Department of Bioresource and Environmental Security, Sandia National Laboratories, Livermore, CA, United States
| | - Alberto Rodriguez
- Department of Biomaterials and Biomanufacturing, Sandia National Laboratories, Livermore, CA, United States,Joint BioEnergy Institute, Emeryville, CA, United States
| | - Zohal Wardak
- Department of Bioresource and Environmental Security, Sandia National Laboratories, Livermore, CA, United States
| | - Abigail Jansen
- Chemical Engineering Program, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ, United States
| | - John M. Gladden
- Department of Biomaterials and Biomanufacturing, Sandia National Laboratories, Livermore, CA, United States,Joint BioEnergy Institute, Emeryville, CA, United States
| | - Anthe George
- Department of Bioresource and Environmental Security, Sandia National Laboratories, Livermore, CA, United States,Department of Biomaterials and Biomanufacturing, Sandia National Laboratories, Livermore, CA, United States
| | - Ryan W. Davis
- Department of Bioresource and Environmental Security, Sandia National Laboratories, Livermore, CA, United States,*Correspondence: Ryan W. Davis, ; Arul M. Varman,
| | - Arul M. Varman
- Chemical Engineering Program, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ, United States,*Correspondence: Ryan W. Davis, ; Arul M. Varman,
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Fazili ABA, Shah AM, Zan X, Naz T, Nosheen S, Nazir Y, Ullah S, Zhang H, Song Y. Mucor circinelloides: a model organism for oleaginous fungi and its potential applications in bioactive lipid production. Microb Cell Fact 2022; 21:29. [PMID: 35227264 PMCID: PMC8883733 DOI: 10.1186/s12934-022-01758-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/10/2022] [Indexed: 11/10/2022] Open
Abstract
Microbial oils have gained massive attention because of their significant role in industrial applications. Currently plants and animals are the chief sources of medically and nutritionally important fatty acids. However, the ever-increasing global demand for polyunsaturated fatty acids (PUFAs) cannot be met by the existing sources. Therefore microbes, especially fungi, represent an important alternative source of microbial oils being investigated. Mucor circinelloides—an oleaginous filamentous fungus, came to the forefront because of its high efficiency in synthesizing and accumulating lipids, like γ-linolenic acid (GLA) in high quantity. Recently, mycelium of M. circinelloides has acquired substantial attraction towards it as it has been suggested as a convenient raw material source for the generation of biodiesel via lipid transformation. Although M. circinelloides accumulates lipids naturally, metabolic engineering is found to be important for substantial increase in their yields. Both modifications of existing pathways and re-formation of biosynthetic pathways in M. circinelloides have shown the potential to improve lipid levels. In this review, recent advances in various important metabolic aspects of M. circinelloides have been discussed. Furthermore, the potential applications of M. circinelloides in the fields of antioxidants, nutraceuticals, bioremediation, ethanol production, and carotenoids like beta carotene and astaxanthin having significant nutritional value are also deliberated.
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Effect of Zinc-Calcium on Xylose Consumption by Mucor circinelloides (MN128960): Xylitol and Ethanol Yield Optimization. ENERGIES 2022. [DOI: 10.3390/en15030906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Xylose is the second most abundant monomeric sugar on earth. Nevertheless, metabolizing xylose into ethanol is a complex process due to several biochemical reactions. Some microorganisms of the genus Mucor are suitable for this bioprocess. Using metal ions, such as zinc and calcium, allows some fungal species to increase their ethanol yield. In this work, the wild strain Mucor spp. (C1502) was molecularly identified via internal transcribed spacer (ITS) sequencing. Secondly, an optimization using response surface methodology (RSM) with a central composite experimental design (CCD) was carried out. The independent variables (X) were ZnSO4·7H2O (X1, 0.0–1.5 g/L) and CaCl2 (X2, 0.0–2.5 g/L) concentration in the fermentation broth in order to demonstrate the effect of these ions, xylose was used as the only carbon source. The dependent variables (Y) measured were ethanol yield (Y1, g ethanol/g xylose) and xylitol yield (Y2, g xylitol/g xylose). The identified strain, Mucor circinelloides, was given the accession number MN128960 by the NCBI. Once the optimal concentrations of zinc and calcium were calculated, experimental validation was performed, with the highest ethanol and xylitol yields reaching 0.36 g ethanol/g xylose and 0.35 g xylitol/g xylose, respectively. This study demonstrated that increasing the xylitol yield using the effect of the ions, zinc and calcium, increases the ethanol yield. Furthermore, M. circinelloides (C1502) can produce metabolites, such as ethanol and xylitol, from the xylose obtained from hemicellulose biomasses, which can be used as a carbon source at low cost and with great availability.
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Uprety BK, Morrison EN, Emery RJN, Farrow SC. Customizing lipids from oleaginous microbes: leveraging exogenous and endogenous approaches. Trends Biotechnol 2021; 40:482-508. [PMID: 34625276 DOI: 10.1016/j.tibtech.2021.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/08/2021] [Accepted: 09/10/2021] [Indexed: 12/22/2022]
Abstract
To meet the growing demands of the oleochemical industry, tailored lipid sources are expanding to oleaginous microbes. To control the fatty acid composition of microbial lipids, ground-breaking exogenous and endogenous approaches are being developed. Exogenous approaches employ extracellular tools such as product-specific feedstocks, process optimization, elicitors, and magnetic and mechanical energy, whereas endogenous approaches leverage biology through the use of product-specific microbes, adaptive laboratory evolution (ALE), and the creation of custom strains via random and targeted cellular engineering. We consolidate recent advances from both fields into a review that will serve as a resource for those striving to fulfill the vision of microbial cell factories for tailored lipid production.
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Affiliation(s)
- Bijaya K Uprety
- Discovery Biology, Noblegen Inc., Peterborough, ON K9L 1Z8, Canada; Biology Department, Trent University, Peterborough, ON K9L 0G2, Canada
| | - Erin N Morrison
- Discovery Biology, Noblegen Inc., Peterborough, ON K9L 1Z8, Canada; Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON K9L 0G2, Canada
| | - R J Neil Emery
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON K9L 0G2, Canada; Biology Department, Trent University, Peterborough, ON K9L 0G2, Canada
| | - Scott C Farrow
- Discovery Biology, Noblegen Inc., Peterborough, ON K9L 1Z8, Canada; Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON K9L 0G2, Canada.
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