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Wang X, Li S, Pang S, Liu Q, Song Y. Regulation of AreA on lipid biosynthesis under different nitrogen sources and C/N ratios in the model oleaginous fungus Mucor circinelloides. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159537. [PMID: 39032627 DOI: 10.1016/j.bbalip.2024.159537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 06/03/2024] [Accepted: 07/17/2024] [Indexed: 07/23/2024]
Abstract
Mucor circinelloides has been exploited as model filamentous fungi for studies of genetic manipulation of lipogenesis. It is widely recognized that lipid accumulation is increased when there is a lack of nitrogen source in oleaginous microorganism. Nitrogen metabolism in filamentous fungi is a complex process that can be regulated by the global nitrogen regulator AreA. In this study, we cultivated the areA-knockout and -overexpression strains obtained in our previous study, using 20 different nitrogen sources. It emerged that the disruption of AreA in M. circinelloides reduced its sensitivity to nitrogen availability, resulting in increased lipid synthesis. Specially, the areA-knockout strain was unable to fully utilize many nitrogen sources but the ammonium and glutamate. We continued to investigate lipid production at different molar C/N ratios using glucose as sole carbon source and ammonium sulfate as sole nitrogen source, of which the high C/N ratios activate high lipid accumulation. By comparing the experimental results with transcriptional analysis, we were able to identify the optimal process conditions suitable for lipid accumulation and potential targets for future metabolic engineering.
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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 255000, Shandong, China
| | - Shaoqi Li
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, Shandong, China
| | - Shuxian Pang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, Shandong, China
| | - Qing Liu
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, Shandong, China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, Shandong, China.
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2
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Tang YX, Huang W, Wang YH, Chen H, Lu XY, Tian Y, Ji XJ, Liu HH. Engineering Yarrowia lipolytica for sustainable Cis-13, 16-docosadienoic acid production. BIORESOURCE TECHNOLOGY 2024; 406:130978. [PMID: 38879057 DOI: 10.1016/j.biortech.2024.130978] [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: 03/05/2024] [Revised: 05/31/2024] [Accepted: 06/12/2024] [Indexed: 06/19/2024]
Abstract
Cis-13, 16-docosadienoic acid (DDA) is an omega-6 polyunsaturated fatty acid with great potential for application in medicine and health. Using microbial cell factories for DDA production is considered a viable alternative to extracting DDA from plant seeds. In this study, using Yarrowia lipolytica Po1f (Δku70) as a chassis, firstly, the adaptation of three elongases in Po1f (Δku70) were explored. Secondly, the DDA biosynthetic pathway was redesigned, resulting in a DDA content of 0.046 % of total fatty acids (TFAs). Thirdly, through the "push-pull" strategy, the DDA content increased to 0.078 % of TFAs. By enhancing the supply of acetyl-CoA, the DDA production in the engineered strain YL-7 reached 0.391 % of the TFAs (3.19 mg/L). Through optimizing the fermentation conditions, the DDA titer of YL-7 reached 29.34 mg/L. This research achieves the sustainable biological production of DDA in Y. lipolytica.
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Affiliation(s)
- Yi-Xiong Tang
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Wei Huang
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Yu-Hui Wang
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Hong Chen
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Xiang-Yang Lu
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Yun Tian
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China; State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, China
| | - Xiao-Jun Ji
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, Jiangsu 211816, China
| | - Hu-Hu Liu
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China.
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Yan CX, Zhang Y, Yang WQ, Ma W, Sun XM, Huang H. Universal and unique strategies for the production of polyunsaturated fatty acids in industrial oleaginous microorganisms. Biotechnol Adv 2024; 70:108298. [PMID: 38048920 DOI: 10.1016/j.biotechadv.2023.108298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 11/21/2023] [Accepted: 12/01/2023] [Indexed: 12/06/2023]
Abstract
Polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (ARA), are beneficial for reducing blood cholesterol and enhancing memory. Traditional PUFA production relies on extraction from plants and animals, which is unsustainable. Thus, using microorganisms as lipid-producing factories holds promise as an alternative way for PUFA production. Several oleaginous microorganisms have been successfully industrialized to date. These can be divided into universal and specialized hosts according to the products range of biosynthesis. The Yarrowia lipolytica is universal oleaginous host that has been engineered to produce a variety of fatty acids, such as γ-linolenic acid (GLA), EPA, ARA and so on. By contrast, the specialized host are used to produce only certain fatty acids, such as ARA in Mortierella alpina, EPA in Nannochloropsis, and DHA in Thraustochytrids. The metabolic engineering and fermentation strategies for improving PUFA production in universal and specialized hosts are different, which is the subject of this review. In addition, the widely applicable strategies for microbial lipid production that are not specific to individual hosts were also reviewed.
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Affiliation(s)
- Chun-Xiao Yan
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 2 Xuelin Road, Qixia District, Nanjing, People's Republic of China
| | - Ying Zhang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 2 Xuelin Road, Qixia District, Nanjing, People's Republic of China
| | - Wen-Qian Yang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 2 Xuelin Road, Qixia District, Nanjing, People's Republic of China
| | - Wang Ma
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 2 Xuelin Road, Qixia District, Nanjing, People's Republic of China
| | - Xiao-Man Sun
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 2 Xuelin Road, Qixia District, Nanjing, People's Republic of China.
| | - He Huang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 2 Xuelin Road, Qixia District, Nanjing, People's Republic of China
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4
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Liu Y, Han X, Dai Y, Chen Z. bZIP transcription factor FabR: Redox-dependent mechanism controlling docosahexaenoic acid biosynthesis and H 2O 2 stress response in Schizochytrium sp. Free Radic Biol Med 2024; 210:246-257. [PMID: 38042223 DOI: 10.1016/j.freeradbiomed.2023.11.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/20/2023] [Accepted: 11/26/2023] [Indexed: 12/04/2023]
Abstract
Schizochytrium sp. is an important industrial strain for commercial production of docosahexaenoic acid (DHA), which plays essential physiological roles in infant development and human health. The regulatory network for DHA biosynthesis and lipid accumulation in Schizochytrium remains poorly understood. FabR (fatty acid biosynthesis repressor), a basic leucine zipper (bZIP) transcription factor, was transcriptionally downregulated under low-nitrogen condition. Deletion of fabR gene (mutant ΔfabR) increased production of total lipids and DHA by 30.1% and 46.5%, respectively. ΔfabR displayed H2O2 stress resistance higher than that of parental strain or complementation strain CfabR. FabR bound specifically to 7-bp pseudo-palindromic sequence 5'-ATTSAAT-3' in upstream regions and repressed transcription of fatty acid biosynthesis genes (acl, fas, pfa) and antioxidant defense genes (cat, sod1, sod2, gpx). DNA binding activity of FabR was regulated in a redox-dependent manner. Under oxidative condition, FabR forms intermolecular disulfide bonds between two Cys46 residues of dimers; its DNA binding activity is thereby lost, and the transcription of its target genes is enhanced through derepression. Our findings clarify the redox-dependent mechanism that modulates FabR activity governing lipid and DHA biosynthesis and H2O2 stress response in Schizochytrium.
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Affiliation(s)
- Yana Liu
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiao Han
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yujie Dai
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Zhi Chen
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
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Jovanovic Gasovic S, Dietrich D, Gläser L, Cao P, Kohlstedt M, Wittmann C. Multi-omics view of recombinant Yarrowia lipolytica: Enhanced ketogenic amino acid catabolism increases polyketide-synthase-driven docosahexaenoic production to high selectivity at the gram scale. Metab Eng 2023; 80:45-65. [PMID: 37683719 DOI: 10.1016/j.ymben.2023.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 09/04/2023] [Accepted: 09/04/2023] [Indexed: 09/10/2023]
Abstract
DHA is a marine PUFA of commercial value, given its multiple health benefits. The worldwide emerging shortage in DHA supply has increased interest in microbial cell factories that can provide the compound de novo. In this regard, the present work aimed to improve DHA production in the oleaginous yeast strain Y. lipolytica Af4, which synthetized the PUFA via a heterologous myxobacterial polyketide synthase (PKS)-like gene cluster. As starting point, we used transcriptomics, metabolomics, and 13C-based metabolic pathway profiling to study the cellular dynamics of Y. lipolytica Af4. The shift from the growth to the stationary DHA-production phase was associated with fundamental changes in carbon core metabolism, including a strong upregulation of the PUFA gene cluster, as well as an increase in citrate and fatty acid degradation. At the same time, the intracellular levels of the two DHA precursors acetyl-CoA and malonyl-CoA dropped by up to 98% into the picomolar range. Interestingly, the degradation pathways for the ketogenic amino acids l-lysine, l-leucine, and l-isoleucine were transcriptionally activated, presumably to provide extra acetyl-CoA. Supplementation with small amounts of these amino acids at the beginning of the DHA production phase beneficially increased the intracellular CoA-ester pools and boosted the DHA titer by almost 40%. Isotopic 13C-tracer studies revealed that the supplements were efficiently directed toward intracellular CoA-esters and DHA. Hereby, l-lysine was found to be most efficient, as it enabled long-term activation, due to storage within the vacuole and continuous breakdown. The novel strategy enabled DHA production in Y. lipolytica at the gram scale for the first time. DHA was produced at a high selectivity (27% of total fatty acids) and free of the structurally similar PUFA DPA, which facilitates purification for high-value medical applications that require API-grade DHA. The assembled multi-omics picture of the central metabolism of Y. lipolytica provides valuable insights into this important yeast. Beyond our work, the enhanced catabolism of ketogenic amino acids seems promising for the overproduction of other compounds in Y. lipolytica, whose synthesis is limited by the availability of CoA ester precursors.
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Affiliation(s)
| | - Demian Dietrich
- Institute of Systems Biotechnology, Saarland University, Germany
| | - Lars Gläser
- Institute of Systems Biotechnology, Saarland University, Germany
| | - Peng Cao
- Institute of Systems Biotechnology, Saarland University, Germany
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Brink DP, Mierke F, Norbeck J, Siewers V, Andlid T. Expanding the genetic toolbox of Rhodotorula toruloides by identification and validation of six novel promoters induced or repressed under nitrogen starvation. Microb Cell Fact 2023; 22:160. [PMID: 37598166 PMCID: PMC10440040 DOI: 10.1186/s12934-023-02175-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 08/09/2023] [Indexed: 08/21/2023] Open
Abstract
BACKGROUND The non-conventional yeast Rhodotorula toruloides is an emerging host organism in biotechnology by merit of its natural capacity to accumulate high levels of carotenoids and intracellular storage lipids from a variety of carbon sources. While the number of genetic engineering strategies that employ R. toruloides is increasing, the lack of genetic tools available for modification of this yeast is still limiting strain development. For instance, several strong, constitutive R. toruloides promoters have been characterized, but to date, only five inducible promoters have been identified. Although nitrogen-limited cultivation conditions are commonly used to induce lipid accumulation in this yeast, no promoters regulated by nitrogen starvation have been described for R. toruloides. RESULTS In this study, we used a combination of genomics and transcriptomics methods to identify novel R. toruloides promoter sequences that are either inducible or repressible by nitrogen starvation. RNA sequencing was used to assess gene expression in the recently isolated strain R. toruloides BOT-A2 during exponential growth and during nitrogen starvation, when cultivated with either glucose or xylose as the carbon source. The genome of BOT-A2 was sequenced using a combination of long- and short-read sequencing and annotated with support of the RNAseq data. Differential expression analysis was used to identify genes with a |log2 fold change|≥ 2 when comparing their expression during nitrogen depletion to that during exponential growth. The promoter regions from 16 of these genes were evaluated for their ability to drive the expression of a fluorescent reporter gene. Three promoters that were clearly upregulated under nitrogen starvation and three that were downregulated were selected and further characterized. One promoter, derived from gene RTBOTA2_003877, was found to function like an on-off switch, as it was only upregulated under full nitrogen depletion and downregulated in the presence of the nitrogen source. CONCLUSIONS Six new R. toruloides promoters that were either upregulated or downregulated under nitrogen-starvation were identified. These substantially contribute to the available promoters when engineering this organism and are foreseen to be particularly useful for future engineering strategies requiring specific regulation of target genes in accordance with nitrogen availability.
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Affiliation(s)
- Daniel P Brink
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
- Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Friederike Mierke
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Joakim Norbeck
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Verena Siewers
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden.
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark.
| | - Thomas Andlid
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
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Gorczyca M, Nicaud JM, Celińska E. Transcription factors enhancing synthesis of recombinant proteins and resistance to stress in Yarrowia lipolytica. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12607-z. [PMID: 37318637 DOI: 10.1007/s00253-023-12607-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/11/2023] [Accepted: 05/17/2023] [Indexed: 06/16/2023]
Abstract
Resistance to environmental stress and synthesis of recombinant proteins (r-Prots) are both complex, strongly interconnected biological traits relying on orchestrated contribution of multiple genes. This, in turn, makes their engineering a challenging task. One of the possible strategies is to modify the operation of transcription factors (TFs) associated with these complex traits. The aim of this study was to examine the potential implications of selected five TFs (HSF1-YALI0E13948g, GZF1-YALI0D20482g, CRF1-YALI0B08206g, SKN7-YALI0D14520g, and YAP-like-YALI0D07744g) in stress resistance and/or r-Prot synthesis in Yarrowia lipolytica. The selected TFs were over-expressed or deleted (OE/KO) in a host strain synthesizing a reporter r-Prot. The strains were subjected to phenotype screening under different environmental conditions (pH, oxygen availability, temperature, and osmolality), and the obtained data processing was assisted by mathematical modeling. The results demonstrated that growth and the r-Prot yields under specific conditions can be significantly increased or decreased due to the TFs' engineering. Environmental factors "awakening" individual TFs were indicated, and their contribution was mathematically described. For example, OE of Yap-like TF was proven to alleviate growth retardation under high pH, while Gzf1 and Hsf1 were shown to serve as universal enhancers of r-Prot production in Y. lipolytica. On the other hand, KO of SKN7 and HSF1 disabled growth under hyperosmotic stress. This research demonstrates the usefulness of the TFs engineering approach in the manipulation of complex traits and evidences newly identified functions of the studied TFs. KEY POINTS: • Function and implication in complex traits of 5 TFs in Y. lipolytica were studied. • Gzf1 and Hsf1 are the universal r-Prots synthesis enhancers in Y. lipolytica. • Yap-like TF's activity is pH-dependent; Skn7 and Hsf1 act in osmostress response.
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Affiliation(s)
- Maria Gorczyca
- Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, 60-637, Poznań, Poland
| | - Jean-Marc Nicaud
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | - Ewelina Celińska
- Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, 60-637, Poznań, Poland.
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Mierke F, Brink DP, Norbeck J, Siewers V, Andlid T. Functional genome annotation and transcriptome analysis of Pseudozyma hubeiensis BOT-O, an oleaginous yeast that utilizes glucose and xylose at equal rates. Fungal Genet Biol 2023; 166:103783. [PMID: 36870442 DOI: 10.1016/j.fgb.2023.103783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 02/10/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023]
Abstract
Pseudozyma hubeiensis is a basidiomycete yeast that has the highly desirable traits for lignocellulose valorisation of being equally efficient at utilization of glucose and xylose, and capable of their co-utilization. The species has previously mainly been studied for its capacity to produce secreted biosurfactants in the form of mannosylerythritol lipids, but it is also an oleaginous species capable of accumulating high levels of triacylglycerol storage lipids during nutrient starvation. In this study, we aimed to further characterize the oleaginous nature of P. hubeiensis by evaluating metabolism and gene expression responses during storage lipid formation conditions with glucose or xylose as a carbon source. The genome of the recently isolated P. hubeiensis BOT-O strain was sequenced using MinION long-read sequencing and resulted in the most contiguous P. hubeiensis assembly to date with 18.95 Mb in 31 contigs. Using transcriptome data as experimental support, we generated the first mRNA-supported P. hubeiensis genome annotation and identified 6540 genes. 80% of the predicted genes were assigned functional annotations based on protein homology to other yeasts. Based on the annotation, key metabolic pathways in BOT-O were reconstructed, including pathways for storage lipids, mannosylerythritol lipids and xylose assimilation. BOT-O was confirmed to consume glucose and xylose at equal rates, but during mixed glucose-xylose cultivation glucose was found to be taken up faster. Differential expression analysis revealed that only a total of 122 genes were significantly differentially expressed at a cut-off of |log2 fold change| ≥ 2 when comparing cultivation on xylose with glucose, during exponential growth and during nitrogen-starvation. Of these 122 genes, a core-set of 24 genes was identified that were differentially expressed at all time points. Nitrogen-starvation resulted in a larger transcriptional effect, with a total of 1179 genes with significant expression changes at the designated fold change cut-off compared with exponential growth on either glucose or xylose.
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Affiliation(s)
- Friederike Mierke
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden; Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Daniel P Brink
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden; Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Joakim Norbeck
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Verena Siewers
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden.
| | - Thomas Andlid
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
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9
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Metabolic flux modeling of Gluconobacter oxydans enables improved production of bioleaching organic acids. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.10.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Papiliotrema laurentii: general features and biotechnological applications. Appl Microbiol Biotechnol 2022; 106:6963-6976. [PMID: 36197457 DOI: 10.1007/s00253-022-12208-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 09/12/2022] [Accepted: 09/22/2022] [Indexed: 11/02/2022]
Abstract
Papiliotrema laurentii, previously classified as Cryptococcus laurentii, is an oleaginous yeast that has been isolated from soil, plants, and agricultural and industrial residues. This variety of habitats reflects the diversity of carbon sources that it can metabolize, including monosaccharides, oligosaccharides, glycerol, organic acids, and oils. Compared to other oleaginous yeasts, such as Yarrowia lipolytica and Rhodotorula toruloides, there is little information regarding its genetic and physiological characteristics. From a biotechnological point of view, P. laurentii can produce surfactants, enzymes, and high concentrations of lipids, which can be used as feedstock for fatty acid-derived products. Moreover, it can be applied for the biocontrol of phytopathogenic fungi, contributing to quality maintenance in post- and pre-harvest fruits. It can also improve mycorrhizal colonization, nitrogen nutrition, and plant growth. P. laurentii is also capable of degrading polyester and diesel derivatives and acting in the bioremediation of heavy metals. In this review, we present the current knowledge about the basic and applied aspects of P. laurentii, underscoring its biotechnological potential and future perspectives. KEY POINTS: • The physiological characteristics of P. laurentii confer a wide range of biotechnological applications. • The regulation of the acetyl-CoA carboxylase in P. laurentii is different from most other oleaginous yeasts. • The GEM is a valuable tool to guide the construction of engineered P. laurentii strains with improved features for bio-based products.
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Zhang XY, Li B, Huang BC, Wang FB, Zhang YQ, Zhao SG, Li M, Wang HY, Yu XJ, Liu XY, Jiang J, Wang ZP. Production, Biosynthesis, and Commercial Applications of Fatty Acids From Oleaginous Fungi. Front Nutr 2022; 9:873657. [PMID: 35694158 PMCID: PMC9176664 DOI: 10.3389/fnut.2022.873657] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/31/2022] [Indexed: 12/18/2022] Open
Abstract
Oleaginous fungi (including fungus-like protists) are attractive in lipid production due to their short growth cycle, large biomass and high yield of lipids. Some typical oleaginous fungi including Galactomyces geotrichum, Thraustochytrids, Mortierella isabellina, and Mucor circinelloides, have been well studied for the ability to accumulate fatty acids with commercial application. Here, we review recent progress toward fermentation, extraction, of fungal fatty acids. To reduce cost of the fatty acids, fatty acid productions from raw materials were also summarized. Then, the synthesis mechanism of fatty acids was introduced. We also review recent studies of the metabolic engineering strategies have been developed as efficient tools in oleaginous fungi to overcome the biochemical limit and to improve production efficiency of the special fatty acids. It also can be predictable that metabolic engineering can further enhance biosynthesis of fatty acids and change the storage mode of fatty acids.
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Affiliation(s)
- Xin-Yue Zhang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Bing Li
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Bei-Chen Huang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Feng-Biao Wang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Yue-Qi Zhang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Shao-Geng Zhao
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Min Li
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Hai-Ying Wang
- Key Laboratory of Sustainable Development of Polar Fishery, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Xin-Jun Yu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Xiao-Yan Liu
- Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Huaiyin Normal University, Huaian, China
| | - Jing Jiang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, China
| | - Zhi-Peng Wang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
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12
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Celińska E. "Fight-flight-or-freeze" - how Yarrowia lipolytica responds to stress at molecular level? Appl Microbiol Biotechnol 2022; 106:3369-3395. [PMID: 35488934 PMCID: PMC9151528 DOI: 10.1007/s00253-022-11934-x] [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: 03/02/2022] [Revised: 04/14/2022] [Accepted: 04/20/2022] [Indexed: 11/10/2022]
Abstract
Abstract
Yarrowia lipolytica is a popular yeast species employed in multiple biotechnological production processes. High resistance to extreme environmental conditions or metabolic burden triggered by synthetically forced over-synthesis of a target metabolite has its practical consequences. The proud status of an “industrial workhorse” that Y. lipolytica has gained is directly related to such a quality of this species. With the increasing amount of knowledge coming from detailed functional studies and comprehensive omics analyses, it is now possible to start painting the landscape of the molecular background behind stress response and adaptation in Y. lipolytica. This review summarizes the current state-of-art of a global effort in revealing how Y. lipolytica responds to both environmental threats and the intrinsic burden caused by the overproduction of recombinant secretory proteins at the molecular level. Detailed lists of genes, proteins, molecules, and biological processes deregulated upon exposure to external stress factors or affected by over-synthesis of heterologous proteins are provided. Specificities and universalities of Y. lipolytica cellular response to different extrinsic and intrinsic threats are highlighted. Key points • Y. lipolytica as an industrial workhorse is subjected to multiple stress factors. • Cellular responses together with involved genes, proteins, and molecules are reviewed. • Native stress response mechanisms are studied and inspire engineering strategies.
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Affiliation(s)
- Ewelina Celińska
- Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48, 60-627, Poznan, Poland.
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Shah AM, Yang W, Mohamed H, Zhang Y, Song Y. Microbes: A Hidden Treasure of Polyunsaturated Fatty Acids. Front Nutr 2022; 9:827837. [PMID: 35369055 PMCID: PMC8968027 DOI: 10.3389/fnut.2022.827837] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/21/2022] [Indexed: 12/26/2022] Open
Abstract
Microbes have gained a lot of attention for their potential in producing polyunsaturated fatty acids (PUFAs). PUFAs are gaining scientific interest due to their important health-promoting effects on higher organisms including humans. The current sources of PUFAs (animal and plant) have associated limitations that have led to increased interest in microbial PUFAs as most reliable alternative source. The focus is on increasing the product value of existing oleaginous microbes or discovering new microbes by implementing new biotechnological strategies in order to compete with other sources. The multidisciplinary approaches, including metabolic engineering, high-throughput screening, tapping new microbial sources, genome-mining as well as co-culturing and elicitation for the production of PUFAs, have been considered and discussed in this review. The usage of agro-industrial wastes as alternative low-cost substrates in fermentation for high-value single-cell oil production has also been discussed. Multidisciplinary approaches combined with new technologies may help to uncover new microbial PUFA sources that may have nutraceutical and biotechnological importance.
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Affiliation(s)
- Aabid Manzoor Shah
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Sciences, Shandong University of Technology, Zibo, China
| | - Wu Yang
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Sciences, Shandong University of Technology, Zibo, China
| | - Hassan Mohamed
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Sciences, Shandong University of Technology, Zibo, China
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - Yingtong Zhang
- Institute of Agricultural Facilities and Equipment, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yuanda Song
- Colin Ratledge Center of Microbial Lipids, School of Agriculture Engineering and Food Sciences, Shandong University of Technology, Zibo, China
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Autophagy Improves ARA-Rich TAG Accumulation in Mortierella alpina by Regulating Resource Allocation. Microbiol Spectr 2022; 10:e0130021. [PMID: 35138146 PMCID: PMC8881083 DOI: 10.1128/spectrum.01300-21] [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] [Indexed: 12/11/2022] Open
Abstract
The present study was designed to explore the possibility of improving lipid production in oleaginous filamentous fungus Mortierella alpina based on an autophagy regulation strategy. According to multiomics information, vacuolate-centered macroautophagy was identified as the main type of autophagy in M. alpina under nitrogen-limited conditions. Mutation of autophagy-related gene MAatg8 led to impaired fatty acid synthesis, while overexpression of both MAatg8 and phosphatidylserine decarboxylases (MApsd2) showed promoting effects on fatty acid synthesis. MAatg8 overexpression strain with external supply of ethanolamine significantly increased arachidonic acid (ARA)-rich triacylglycerol (TAG) and biomass synthesis in M. alpina, and the final fatty acid content increased by approximately 110% compared with that in the wild-type strain. Metabolomics and lipidomics analyses revealed that cell autophagy enhanced the recycling of preformed carbon, nitrogen, and lipid in mycelium, and the released carbon skeleton and energy were contributed to the accumulation of TAG in M. alpina. This study suggests that regulation of autophagy-related MAatg8-phosphatidylethanolamine (MAatg8-PE) conjugation system could be a promising strategy for attaining higher lipid production and biomass growth. The mechanism of autophagy in regulating nitrogen limitation-induced lipid accumulation elucidated in this study provides a reference for development of autophagy-based strategies for improving nutrient use efficiency and high value-added lipid production by oleaginous microorganism. IMPORTANCE Studies have indicated that functional oil accumulation occurs in oleaginous microorganisms under nitrogen limitation. However, until now, large-scale application of nitrogen-deficiency strategies was limited by low biomass. Therefore, the identification of the critical nodes of nitrogen deficiency-induced lipid accumulation is urgently needed to further guide functional oil production. The significance of our research is in uncovering the function of cell autophagy in the ARA-rich TAG accumulation of oleaginous fungus M. alpina and demonstrating the feasibility of improving lipid production based on an autophagy regulation strategy at the molecular and omics levels. Our study proves that regulation of cell autophagy through the MAatg8-PE conjugation system-related gene overexpression or exogenous supply of ethanolamine would be an efficient strategy to increase and maintain biomass productivity when high TAG content is obtained under nitrogen deficiency, which could be useful for the development of new strategies that will achieve more biomass and maximal lipid productivity.
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Aliyu H, Gorte O, Neumann A, Ochsenreither K. Global Transcriptome Profile of the Oleaginous Yeast Saitozyma podzolica DSM 27192 Cultivated in Glucose and Xylose. J Fungi (Basel) 2021; 7:758. [PMID: 34575796 PMCID: PMC8466774 DOI: 10.3390/jof7090758] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/08/2021] [Accepted: 09/13/2021] [Indexed: 11/29/2022] Open
Abstract
Unlike conventional yeasts, several oleaginous yeasts, including Saitozyma podzolica DSM 27192, possess the innate ability to grow and produce biochemicals from plant-derived lignocellulosic components such as hexose and pentose sugars. To elucidate the genetic basis of S. podzolica growth and lipid production on glucose and xylose, we performed comparative temporal transcriptome analysis using RNA-seq method. Approximately 3.4 and 22.2% of the 10,670 expressed genes were differentially (FDR < 0.05, and log2FC > 1.5) expressed under batch and fed batch modes, respectively. Our analysis revealed that a higher number of sugar transporter genes were significantly overrepresented in xylose relative to glucose-grown cultures. Given the low homology between proteins encoded by most of these genes and those of the well-characterised transporters, it is plausible to conclude that S. podzolica possesses a cache of putatively novel sugar transporters. The analysis also suggests that S. podzolica potentially channels carbon flux from xylose via both the non-oxidative pentose phosphate and potentially via the first steps of the Weimberg pathways to yield xylonic acid. However, only the ATP citrate lyase (ACL) gene showed significant upregulation among the essential oleaginous pathway genes under nitrogen limitation in xylose compared to glucose cultivation. Combined, these findings pave the way toward the design of strategies or the engineering of efficient biomass hydrolysate utilization in S. podzolica for the production of various biochemicals.
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Affiliation(s)
- Habibu Aliyu
- Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany; (O.G.); (A.N.)
| | | | | | - Katrin Ochsenreither
- Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany; (O.G.); (A.N.)
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Poorinmohammad N, Kerkhoven EJ. Systems-level approaches for understanding and engineering of the oleaginous cell factory Yarrowia lipolytica. Biotechnol Bioeng 2021; 118:3640-3654. [PMID: 34129240 DOI: 10.1002/bit.27859] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 03/07/2021] [Accepted: 06/10/2021] [Indexed: 12/12/2022]
Abstract
Concerns about climate change and the search for renewable energy sources together with the goal of attaining sustainable product manufacturing have boosted the use of microbial platforms to produce fuels and high-value chemicals. In this regard, Yarrowia lipolytica has been known as a promising yeast with potentials in diverse array of biotechnological applications such as being a host for different oleochemicals, organic acid, and recombinant protein production. Having a rapidly increasing number of molecular and genetic tools available, Y. lipolytica has been well studied amongst oleaginous yeasts and metabolic engineering has been used to explore its potentials. More recently, with the advancement in systems biotechnology and the implementation of mathematical modeling and high throughput omics data-driven approaches, in-depth understanding of cellular mechanisms of cell factories have been made possible resulting in enhanced rational strain design. In case of Y. lipolytica, these systems-level studies and the related cutting-edge technologies have recently been initiated which is expected to result in enabling the biotechnology sector to rationally engineer Y. lipolytica-based cell factories with favorable production metrics. In this regard, here, we highlight the current status of systems metabolic engineering research and assess the potential of this yeast for future cell factory design development.
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Affiliation(s)
- Naghmeh Poorinmohammad
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Eduard J Kerkhoven
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Jia YL, Wang LR, Zhang ZX, Gu Y, Sun XM. Recent advances in biotechnological production of polyunsaturated fatty acids by Yarrowia lipolytica. Crit Rev Food Sci Nutr 2021; 62:8920-8934. [PMID: 34120537 DOI: 10.1080/10408398.2021.1937041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Owing to the important physiological functions, polyunsaturated fatty acids (PUFAs) play a vital role in protecting human health, such as preventing cancer, cardiovascular disease, and diabetes. Specifically, Yarrowia lipolytica has been identified as the most popular non-conventional oleaginous yeast, which can accumulate the abundant intracellular lipids, indicating that has great potential as an industrial host for production of PUFAs. Notably, some novel engineering strategies have been applied to endow and improve the abilities of Y. lipolytica to synthesize PUFAs, including construction and optimization of PUFAs biosynthetic pathways, improvement of preucrsors acetyl-coA and NADPH supply, inhibition of competing pathways, knockout of β-oxidation pathways, regulation of oxidative stress defense pathways, and regulation of genes involved in upstream lipid metabolism. Besides, some bypass approaches, such as strain mating, evolutionary engineering, and computational model based on omics, also have been proposed to improve the performance of engineering strains. Generally, in this review, we summarized the recent advances in engineering strategies and bypass approaches for improving PUFAs production by Y. lipolytica. In addition, we further summarized the latest efforts of CRISPR/Cas genome editing technology in Y. lipolytica, which is aimed to provide its potential applications in PUFAs production.
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Affiliation(s)
- Yu-Lei Jia
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, People's Republic of China
| | - Ling-Ru Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, People's Republic of China
| | - Zi-Xu Zhang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, People's Republic of China
| | - Yang Gu
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, People's Republic of China
| | - Xiao-Man Sun
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, People's Republic of China
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18
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Mihreteab M, Stubblefield BA, Gilbert ES. Enhancing polypropylene bioconversion and lipogenesis by Yarrowia lipolytica using a chemical/biological hybrid process. J Biotechnol 2021; 332:94-102. [PMID: 33838158 DOI: 10.1016/j.jbiotec.2021.03.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 03/01/2021] [Accepted: 03/16/2021] [Indexed: 11/28/2022]
Abstract
Plastic waste can serve as a feedstock for microbial bioconversion using a chemical/biological hybrid strategy. We developed a polypropylene (PP) upcycling process that coupled pyrolysis with bioconversion by the oleaginous yeast Yarrowia lipolytica. Using virgin PP, we optimized pH, inoculum density, C/N ratio, and osmolarity and increased the fatty acid titer nearly four-fold to 1.9 g L-1, with 41 percent cellular fatty acid content, the highest content reported to date for plastic-to-lipid microbial bioconversion. The highest fatty acid titer was achieved with an inoculum density of 3 (OD 600 nm), pH = 6.0 and C/N ratio of 80:1. Increasing the medium osmolarity by adding sodium chloride adversely affected cell growth and did not improve the fatty acid titer. The maximum fatty acid titer occurred under conditions that balanced cell growth versus lipogenesis. Using postconsumer PP, the fatty acid titer was significantly lower (0.13 g L-1). Overall, the work demonstrates the potential and the challenges associated with microbial bioconversion of plastics.
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Affiliation(s)
- Merhawi Mihreteab
- Biology Department, Georgia State University, Atlanta, GA, 30302-4010, USA.
| | | | - Eric S Gilbert
- Biology Department, Georgia State University, Atlanta, GA, 30302-4010, USA.
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Sestric R, Spicer V, V Krokhin O, Sparling R, B Levin D. Analysis of the Yarrowia lipolytica proteome reveals subtle variations in expression levels between lipogenic and non-lipogenic conditions. FEMS Yeast Res 2021; 21:6133473. [PMID: 33571365 DOI: 10.1093/femsyr/foab007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 02/09/2021] [Indexed: 11/13/2022] Open
Abstract
Oleaginous yeasts have the ability to store greater than 20% of their mass as neutral lipids, in the form of triacylglycerides. The ATP citrate lyase is thought to play a key role in triacylglyceride synthesis, but the relationship between expression levels of this and other related enzymes is not well understood in the role of total lipid accumulation conferring the oleaginous phenotype. We conducted comparative proteomic analyses with the oleaginous yeast, Yarrowia lipolytica, grown in either nitrogen-sufficient rich media or nitrogen-limited minimal media. Total proteins extracted from cells collected during logarithmic and late stationary growth phases were analyzed by 1D liquid chromatography, followed by mass spectroscopy. The ATP citrate lyase enzyme was expressed at similar concentrations in both conditions, in both logarithmic and stationary phase, but many upstream and downstream enzymes showed drastically different expression levels. In non-lipogenic conditions, several pyruvate enzymes were expressed at higher concentration. These enzymes, especially the pyruvate decarboxylase and pyruvate dehydrogenase, may be regulating carbon flux away from central metabolism and reducing the amount of citrate being produced in the mitochondria. While crucial for the oleaginous phenotype, the constitutively expressed ATP citrate lyase appears to cleave citrate in response to carbon flux upstream from other enzymes creating the oleaginous phenotype.
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Affiliation(s)
- Ryan Sestric
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, MB R3T 5V6, Canada
| | - Vic Spicer
- Manitoba Centre for Proteomics and Systems Biology, Department of Internal Medicine, University of Manitoba, Winnipeg, MB R3E 3P4, Canada
| | - Oleg V Krokhin
- Manitoba Centre for Proteomics and Systems Biology, Department of Internal Medicine, University of Manitoba, Winnipeg, MB R3E 3P4, Canada
| | - Richard Sparling
- Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - David B Levin
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, MB R3T 5V6, Canada
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Bredeweg EL, Baker SE. Strain Construction for Intracellular Metabolic Pathway Localization in Y. lipolytica. Methods Mol Biol 2021; 2307:147-157. [PMID: 33847988 DOI: 10.1007/978-1-0716-1414-3_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
Pathway localization by fluorophore or epitope tagging can be accomplished through a multi-staged DNA construct and confirmation process, to generate a series of successfully tagged protein targets. Prerequisite conditions for this process in Y. lipolytica are auxotrophic selection (leu2 or ura3), impaired non-homologous end joining by deletion or impairment of ku70, and plasmids or gene pieces for epitope-selection cassette construction. The general approach for gene tagging can work for C- or N-terminal tags. Gene overexpression from an episomal plasmid can be accomplished through transcript amplification and cloning. C-terminal tagging allows expression of a gene-GFP fusion to be regulated from the endogenous promoter. The epitope-selection cassette also includes a constitutive or highly expressed promoter driving the auxotrophic or other selectable marker gene such as one conferring antifungal or antibiotic resistance. Strains for pathway localization utilize overlap PCR, PEG-based transformation, and a fast DNA preparation for rapid colony screening. Successful transformants can be used for pathway localization and condition-specific response analysis.
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Affiliation(s)
- Erin L Bredeweg
- Environmental and Molecular Sciences Laboratory, PNNL, Richland, WA, USA
| | - Scott E Baker
- Environmental and Molecular Sciences Laboratory, PNNL, Richland, WA, USA.
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González J, Romero-Aguilar L, Matus-Ortega G, Pablo Pardo J, Flores-Alanis A, Segal-Kischinevzky C. Levaduras adaptadas al frío: el tesoro biotecnológico de la Antártica. TIP REVISTA ESPECIALIZADA EN CIENCIAS QUÍMICO-BIOLÓGICAS 2020. [DOI: 10.22201/fesz.23958723e.2020.0.267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Las levaduras son organismos microscópicos que están distribuidos en toda la Tierra, de modo que algunas han adaptado su metabolismo para proliferar en ambientes extremos. Las levaduras que habitan en la Antártica son un grupo de microorganismos adaptados al frío que han sido poco estudiadas. En esta revisión se describen algunas de las adaptaciones metabólicas que les permiten habitar en ambientes extremos, por ejemplo, el de la Antártica. También se abordan las consideraciones relevantes para saber si una levadura es extremófila, así como los criterios utilizados para clasificar a las levaduras por crecimiento y temperatura. Además, se explica el papel de las vías de biosíntesis de carotenoides y lípidos que están involucradas en contrarrestar a las especies reactivas de oxígeno generadas por estrés oxidante en levaduras pigmentadas y oleaginosas del género Rhodotorula. La revisión también considera aspectos de investigación básica y la importancia de las levaduras oleaginosas de la Antártica para el desarrollo de algunas aplicaciones biotecnológicas.
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Sailwal M, Das AJ, Gazara RK, Dasgupta D, Bhaskar T, Hazra S, Ghosh D. Connecting the dots: Advances in modern metabolomics and its application in yeast system. Biotechnol Adv 2020; 44:107616. [DOI: 10.1016/j.biotechadv.2020.107616] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 08/15/2020] [Accepted: 08/17/2020] [Indexed: 12/15/2022]
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Lu H, Chen H, Tang X, Yang Q, Zhang H, Chen YQ, Chen W. Metabolomics analysis reveals the role of oxygen control in the nitrogen limitation induced lipid accumulation in Mortierella alpina. J Biotechnol 2020; 325:325-333. [PMID: 33039549 DOI: 10.1016/j.jbiotec.2020.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 02/06/2023]
Abstract
Lipid hyperaccumulation in oleaginous microorganisms is generally induced by nitrogen limitation, while oxygen supply can influence biomass growth and cell metabolism. Although strategies based on nitrogen limitation or oxygen control have been extensively explored and applied in various oleaginous microorganisms, the role of oxygen supply in nitrogen limitation induced lipid hyperaccumulation still remains unclear. Here, we systematically surveyed the effects of oxygen supply on the oleaginous fungus M. alpina cultured in nitrogen limited conditions through integration of physiochemical parameters and metabolomics analysis. Our results indicated that a high oxygen supply promoted carbon/nitrogen consumption and was used for rapid biomass synthesis, while either high or low oxygen supply conditions were adverse to lipid and ARA accumulation. Different oxygen supply level significantly affected the balance between fermentation for lipid synthesis and respiration for energy generation. Under nitrogen limitation, a suitable oxygen supply promoted the recycling of preformed nitrogen and increased the redirection of carbon towards fatty acid synthesis through the hub centred around glutamic acid coupled to the intermediate metabolism of carbon in the TCA cycle, while a high oxygen supply favored the respiration process and enhanced the degradation of LC-PUFAs, rather than fermentation for fatty acid synthesis. This system-level insight reveals the underlying metabolic mechanism of oxygen control in nitrogen limitation induced lipid accumulation, and provides theoretical support for the integration of oxygen control with nutrient supply for efficient microbial oil production.
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Affiliation(s)
- Hengqian Lu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Haiqin Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, China; (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou 225004, China.
| | - Xin Tang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Qin Yang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou 225004, China
| | - Yong Q Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, China; Beijing Innovation Centre of Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
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Sáez-Sáez J, Wang G, Marella ER, Sudarsan S, Cernuda Pastor M, Borodina I. Engineering the oleaginous yeast Yarrowia lipolytica for high-level resveratrol production. Metab Eng 2020; 62:51-61. [PMID: 32818629 PMCID: PMC7672257 DOI: 10.1016/j.ymben.2020.08.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 08/12/2020] [Accepted: 08/12/2020] [Indexed: 01/05/2023]
Abstract
Resveratrol is a plant secondary metabolite with multiple health-beneficial properties. Microbial production of resveratrol in model microorganisms requires extensive engineering to reach commercially viable levels. Here, we explored the potential of the non-conventional yeast Yarrowia lipolytica to produce resveratrol and several other shikimate pathway-derived metabolites (p-coumaric acid, cis,cis-muconic acid, and salicylic acid). The Y. lipolytica strain expressing a heterologous pathway produced 52.1 ± 1.2 mg/L resveratrol in a small-scale cultivation. The titer increased to 409.0 ± 1.2 mg/L when the strain was further engineered with feedback-insensitive alleles of the key genes in the shikimate pathway and with five additional copies of the heterologous biosynthetic genes. In controlled fed-batch bioreactor, the strain produced 12.4 ± 0.3 g/L resveratrol, the highest reported titer to date for de novo resveratrol production, with a yield on glucose of 54.4 ± 1.6 mg/g and a productivity of 0.14 ± 0.01 g/L/h. The study showed that Y. lipolytica is an attractive host organism for the production of resveratrol and possibly other shikimate-pathway derived metabolites. Oleaginous yeast Y. lipolytica was engineered for production of aromatic compounds. High resveratrol production required increased activities of Aro4p and Aro7p. Multiple integration of resveratrol biosynthetic genes improved production. Fed-batch fermentation enabled de novo production of 12.4 g/L resveratrol.
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Affiliation(s)
- Javier Sáez-Sáez
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Guokun Wang
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark.
| | - Eko Roy Marella
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Suresh Sudarsan
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Marc Cernuda Pastor
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Irina Borodina
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark.
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Patel A, Karageorgou D, Rova E, Katapodis P, Rova U, Christakopoulos P, Matsakas L. An Overview of Potential Oleaginous Microorganisms and Their Role in Biodiesel and Omega-3 Fatty Acid-Based Industries. Microorganisms 2020; 8:E434. [PMID: 32204542 PMCID: PMC7143722 DOI: 10.3390/microorganisms8030434] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 12/17/2022] Open
Abstract
Microorganisms are known to be natural oil producers in their cellular compartments. Microorganisms that accumulate more than 20% w/w of lipids on a cell dry weight basis are considered as oleaginous microorganisms. These are capable of synthesizing vast majority of fatty acids from short hydrocarbonated chain (C6) to long hydrocarbonated chain (C36), which may be saturated (SFA), monounsaturated (MUFA), or polyunsaturated fatty acids (PUFA), depending on the presence and number of double bonds in hydrocarbonated chains. Depending on the fatty acid profile, the oils obtained from oleaginous microorganisms are utilized as feedstock for either biodiesel production or as nutraceuticals. Mainly microalgae, bacteria, and yeasts are involved in the production of biodiesel, whereas thraustochytrids, fungi, and some of the microalgae are well known to be producers of very long-chain PUFA (omega-3 fatty acids). In this review article, the type of oleaginous microorganisms and their expertise in the field of biodiesel or omega-3 fatty acids, advances in metabolic engineering tools for enhanced lipid accumulation, upstream and downstream processing of lipids, including purification of biodiesel and concentration of omega-3 fatty acids are reviewed.
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Affiliation(s)
- Alok Patel
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (A.P.); (E.R.); (U.R.); (P.C.)
| | - Dimitra Karageorgou
- Laboratory of Biotechnology, Department of Biological Applications and Technologies, University of Ioannina, Ioannina 45110, Greece; (D.K.); (P.K.)
| | - Emma Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (A.P.); (E.R.); (U.R.); (P.C.)
| | - Petros Katapodis
- Laboratory of Biotechnology, Department of Biological Applications and Technologies, University of Ioannina, Ioannina 45110, Greece; (D.K.); (P.K.)
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (A.P.); (E.R.); (U.R.); (P.C.)
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (A.P.); (E.R.); (U.R.); (P.C.)
| | - Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden; (A.P.); (E.R.); (U.R.); (P.C.)
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Lu H, Chen H, Tang X, Yang Q, Zhang H, Chen YQ, Chen W. Time-resolved multi-omics analysis reveals the role of nutrient stress-induced resource reallocation for TAG accumulation in oleaginous fungus Mortierella alpina. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:116. [PMID: 32625246 PMCID: PMC7328260 DOI: 10.1186/s13068-020-01757-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 06/23/2020] [Indexed: 05/04/2023]
Abstract
BACKGROUND Global resource reallocation is an established critical strategy through which organisms deal with environmental stress. The regulation of intracellular lipid storage or utilization is one of the most important strategies for maintaining energy homeostasis and optimizing growth. Oleaginous microorganisms respond to nitrogen deprivation by inducing lipid hyper accumulation; however, the associations between resource allocation and lipid accumulation are poorly understood. RESULTS Here, the time-resolved metabolomics, lipidomics, and proteomics data were generated in response to nutrient availability to examine how metabolic alternations induced by nitrogen deprivation drive the triacylglycerols (TAG) accumulation in M. alpina. The subsequent accumulation of TAG under nitrogen deprivation was a consequence of the reallocation of carbon, nitrogen sources, and lipids, rather than an up-regulation of TAG biosynthesis genes. On one hand, nitrogen deprivation induced the down-regulation of isocitrate dehydrogenase level in TCA cycle and redirected glycolytic flux of carbon from amino acid biosynthesis into fatty acids' synthesis; on the other hand, nitrogen deprivation induced the up-regulation of cell autophagy and ubiquitin-mediated protein proteolysis which resulted in a recycling of preformed protein nitrogen and carbon. Combining with the up-regulation of glutamate decarboxylase and succinic semialdehyde dehydrogenase in GABA shunt, and the phosphoenolpyruvate carboxykinase in the central hub involving pyruvate/phosphoenolpyruvate/oxaloacetate, the products from nitrogen-containing compounds degradation were recycled to be intermediates of TCA cycle and be shunted toward de novo biosynthesis of fatty acids. We found that nitrogen deprivation increased the protein level of phospholipase C/D that contributes to degradation of phosphatidylcholine and phosphatidylethanolamine, and supplied acyl chains for TAG biosynthesis pathway. In addition, ATP from substrate phosphorylation was presumed to be a critical factor regulation of the global resource allocation and fatty acids' synthesis rate. CONCLUSIONS The present findings offer a panoramic view of resource allocation by M. alpina in response to nutrient stress and revealed a set of intriguing associations between resource reallocation and TAG accumulation. This system-level insight provides a rich resource with which to explore in-depth functional characterization and gain information about the strategic combination of strain development and process integration to achieve optimal lipid productivity under nutrient stress.
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Affiliation(s)
- Hengqian Lu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Ave, Wuxi, 214122 Jiangsu People’s Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Haiqin Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Ave, Wuxi, 214122 Jiangsu People’s Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, 214122 Jiangsu China
- (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou, 225004 China
| | - Xin Tang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Ave, Wuxi, 214122 Jiangsu People’s Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Qin Yang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Ave, Wuxi, 214122 Jiangsu People’s Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Ave, Wuxi, 214122 Jiangsu People’s Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
- (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou, 225004 China
| | - Yong Q. Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Ave, Wuxi, 214122 Jiangsu People’s Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, 214122 Jiangsu China
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC USA
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Ave, Wuxi, 214122 Jiangsu People’s Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, 214122 Jiangsu China
- Beijing Innovation Centre of Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing, 100048 China
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Awad D, Brueck T. Optimization of protein isolation by proteomic qualification from Cutaneotrichosporon oleaginosus. Anal Bioanal Chem 2020; 412:449-462. [PMID: 31797019 PMCID: PMC6992551 DOI: 10.1007/s00216-019-02254-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/23/2019] [Accepted: 10/30/2019] [Indexed: 11/03/2022]
Abstract
In the last decades, microbial oils have been extensively investigated as a renewable platform for biofuel and oleochemical production. Offering a potent alternative to plant-based oils, oleaginous microorganisms have been the target of ongoing metabolic engineering aimed at increasing growth and lipid yields, in addition to specialty fatty acids. Discovery proteomics is an attractive tool for elucidating lipogenesis and identifying metabolic bottlenecks, feedback regulation, and competing biosynthetic pathways. One prominent microbial oil producer is Cutaneotrichosporon oleaginosus, due to its broad feedstock catabolism and high lipid yield. However, this yeast has a recalcitrant cell wall and high cell lipid content, which complicates efficient and unbiased protein extraction for downstream proteomic analysis. Optimization efforts of protein sample preparation from C. oleaginosus in the present study encompasses the comparison of 8 lysis methods, 13 extraction buffers, and 17 purification methods with respect to protein abundance, proteome coverage, applicability, and physiochemical properties (pI, MW, hydrophobicity in addition to COG, and GO analysis). The optimized protocol presented in this work entails a one-step extraction method utilizing an optimal lysis method (liquid homogenization), which is augmented with a superior extraction buffer (50 mM Tris, 8/2 M Urea/Thiourea, and 1% C7BzO), followed by either of 2 advantageous purification methods (hexane/ethanol or TCA/acetone), depending on subsequent applications and target studies. This work presents a significant step forward towards implementation of efficient C. oleaginosus proteome mining for the identification of potential targets for genetic optimization of this yeast to improve lipogenesis and production of specialty lipids. Graphical abstract.
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Affiliation(s)
- Dania Awad
- Werner Siemens-Lehrstuhl für Synthetische Biotechnologie, Technische Universität München, Lichtenbergstrasse 4, 85748, Garching, Germany
| | - Thomas Brueck
- Werner Siemens-Lehrstuhl für Synthetische Biotechnologie, Technische Universität München, Lichtenbergstrasse 4, 85748, Garching, Germany.
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Russmayer H, Egermeier M, Kalemasi D, Sauer M. Spotlight on biodiversity of microbial cell factories for glycerol conversion. Biotechnol Adv 2019; 37:107395. [DOI: 10.1016/j.biotechadv.2019.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 04/28/2019] [Accepted: 05/02/2019] [Indexed: 12/28/2022]
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Dahlin J, Holkenbrink C, Marella ER, Wang G, Liebal U, Lieven C, Weber D, McCloskey D, Ebert BE, Herrgård MJ, Blank LM, Borodina I, Wang HL. Multi-Omics Analysis of Fatty Alcohol Production in Engineered Yeasts Saccharomyces cerevisiae and Yarrowia lipolytica. Front Genet 2019; 10:747. [PMID: 31543895 PMCID: PMC6730484 DOI: 10.3389/fgene.2019.00747] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/17/2019] [Indexed: 12/02/2022] Open
Abstract
Fatty alcohols are widely used in various applications within a diverse set of industries, such as the soap and detergent industry, the personal care, and cosmetics industry, as well as the food industry. The total world production of fatty alcohols is over 2 million tons with approximately equal parts derived from fossil oil and from plant oils or animal fats. Due to the environmental impact of these production methods, there is an interest in alternative methods for fatty alcohol production via microbial fermentation using cheap renewable feedstocks. In this study, we aimed to obtain a better understanding of how fatty alcohol biosynthesis impacts the host organism, baker’s yeast Saccharomyces cerevisiae or oleaginous yeast Yarrowia lipolytica. Producing and non-producing strains were compared in growth and nitrogen-depletion cultivation phases. The multi-omics analysis included physiological characterization, transcriptome analysis by RNAseq, 13Cmetabolic flux analysis, and intracellular metabolomics. Both species accumulated fatty alcohols under nitrogen-depletion conditions but not during growth. The fatty alcohol–producing Y. lipolytica strain had a higher fatty alcohol production rate than an analogous S. cerevisiae strain. Nitrogen-depletion phase was associated with lower glucose uptake rates and a decrease in the intracellular concentration of acetyl–CoA in both yeast species, as well as increased organic acid secretion rates in Y. lipolytica. Expression of the fatty alcohol–producing enzyme fatty acyl–CoA reductase alleviated the growth defect caused by deletion of hexadecenal dehydrogenase encoding genes (HFD1 and HFD4) in Y. lipolytica. RNAseq analysis showed that fatty alcohol production triggered a cell wall stress response in S. cerevisiae. RNAseq analysis also showed that both nitrogen-depletion and fatty alcohol production have substantial effects on the expression of transporter encoding genes in Y. lipolytica. In conclusion, through this multi-omics study, we uncovered some effects of fatty alcohol production on the host metabolism. This knowledge can be used as guidance for further strain improvement towards the production of fatty alcohols.
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Affiliation(s)
- Jonathan Dahlin
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Carina Holkenbrink
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Eko Roy Marella
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Guokun Wang
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Ulf Liebal
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Christian Lieven
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Dieter Weber
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Douglas McCloskey
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Birgitta E Ebert
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Markus J Herrgård
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Lars Mathias Blank
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Irina Borodina
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Hong-Lei Wang
- Department of Biology, Lund University, Lund, Sweden
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Trotter PJ, Juco K, Le HT, Nelson K, Tamayo LI, Nicaud JM, Park YK. Glutamate dehydrogenases in the oleaginous yeast Yarrowia lipolytica. Yeast 2019; 37:103-115. [PMID: 31119792 DOI: 10.1002/yea.3425] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 04/25/2019] [Accepted: 05/17/2019] [Indexed: 11/12/2022] Open
Abstract
Glutamate dehydrogenases (GDHs) are fundamental to cellular nitrogen and energy balance. Yet little is known about these enzymes in the oleaginous yeast Yarrowia lipolytica. The YALI0F17820g and YALI0E09603g genes, encoding potential GDH enzymes in this organism, were examined. Heterologous expression in gdh-null Saccharomyces cerevisiae and examination of Y. lipolytica strains carrying gene deletions demonstrate that YALI0F17820g (ylGDH1) encodes a NADP-dependent GDH whereas YALI0E09603g (ylGDH2) encodes a NAD-dependent GDH enzyme. The activity encoded by these two genes accounts for all measurable GDH activity in Y. lipolytica. Levels of the two enzyme activities are comparable during logarithmic growth on rich medium, but the NADP-ylGDH1p enzyme activity is most highly expressed in stationary and nitrogen starved cells by threefold to 12-fold. Replacement of ammonia with glutamate causes a decrease in NADP-ylGdh1p activity, whereas NAD-ylGdh2p activity is increased. When glutamate is both carbon and nitrogen sources, the activity of NAD-ylGDH2p becomes dominant up to 18-fold compared with that of NADP-ylGDH1p. Gene deletion followed by growth on different carbon and nitrogen sources shows that NADP-ylGdh1p is required for efficient nitrogen assimilation whereas NAD-ylGdh2p plays a role in nitrogen and carbon utilization from glutamate. Overexpression experiments demonstrate that ylGDH1 and ylGDH2 are not interchangeable. These studies provide a vital basis for future consideration of how these enzymes function to facilitate energy and nitrogen homeostasis in Y. lipolytica.
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Affiliation(s)
- Pamela J Trotter
- Guehler Biochemistry Research Laboratory, Department of Chemistry, Augustana College, Rock Island, Illinois
| | - Karen Juco
- Guehler Biochemistry Research Laboratory, Department of Chemistry, Augustana College, Rock Island, Illinois
| | - Ha T Le
- Guehler Biochemistry Research Laboratory, Department of Chemistry, Augustana College, Rock Island, Illinois
| | - Kjersten Nelson
- Guehler Biochemistry Research Laboratory, Department of Chemistry, Augustana College, Rock Island, Illinois
| | - Lizeth I Tamayo
- Guehler Biochemistry Research Laboratory, Department of Chemistry, Augustana College, Rock Island, Illinois
| | - Jean-Marc Nicaud
- Biologie intégrative du Métabolisme Lipidique, Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Young-Kyoung Park
- Biologie intégrative du Métabolisme Lipidique, Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
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31
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Pomraning KR, Collett JR, Kim J, Panisko EA, Culley DE, Dai Z, Deng S, Hofstad BA, Butcher MG, Magnuson JK. Transcriptomic analysis of the oleaginous yeast Lipomyces starkeyi during lipid accumulation on enzymatically treated corn stover hydrolysate. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:162. [PMID: 31289462 PMCID: PMC6593508 DOI: 10.1186/s13068-019-1510-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Accepted: 06/19/2019] [Indexed: 05/24/2023]
Abstract
BACKGROUND Efficient and economically viable production of biofuels from lignocellulosic biomass is dependent on mechanical and chemical pretreatment and enzymatic hydrolysis of plant material. These processing steps yield simple sugars as well as plant-derived and process-added organic acids, sugar-derived dehydration products, aldehydes, phenolics and other compounds that inhibit the growth of many microorganisms. Lipomyces starkeyi is an oleaginous yeast capable of robust growth on a variety of sugars and lipid accumulation on pretreated lignocellulosic substrates making it attractive as an industrial producer of biofuels. Here, we examined gene expression during batch growth and lipid accumulation in a 20-L bioreactor with either a blend of pure glucose and xylose or pretreated corn stover (PCS) that had been enzymatically hydrolyzed as the carbon sources. RESULTS We monitored sugar and ammonium utilization as well as biomass accumulation and found that growth of L. starkeyi is inhibited with PCS hydrolysate as the carbon source. Both acetic acid and furfural are present at concentrations toxic to L. starkeyi in PCS hydrolysate. We quantified gene expression at seven time-points for each carbon source during batch growth and found that gene expression is similar at physiologically equivalent points. Analysis of promoter regions revealed that gene expression during the transition to lipid accumulation is regulated by carbon and nitrogen catabolite repression, regardless of carbon source and is associated with decreased expression of the translation machinery and suppression of the cell cycle. We identified 73 differentially expressed genes during growth phase in the bioreactor that may be involved in detoxification of corn stover hydrolysate. CONCLUSIONS Growth of L. starkeyi is inhibited by compounds present in PCS hydrolysate. Here, we monitored key metabolites to establish physiologically equivalent comparisons during a batch bioreactor run comparing PCS hydrolysate and purified sugars. L. starkeyi's response to PCS hydrolysate is primarily at the beginning of the run during growth phase when inhibitory compounds are presumably at their highest concentration and inducing the general detoxification response by L. starkeyi. Differentially expressed genes identified herein during growth phase will aid in the improvement of industrial strains capable of robust growth on substrates containing various growth inhibitory compounds.
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Affiliation(s)
| | | | - Joonhoon Kim
- Pacific Northwest National Laboratory, Richland, WA USA
- Joint BioEnergy Institute, Emeryville, CA USA
| | | | | | - Ziyu Dai
- Pacific Northwest National Laboratory, Richland, WA USA
| | - Shuang Deng
- Pacific Northwest National Laboratory, Richland, WA USA
| | | | | | - Jon K. Magnuson
- Pacific Northwest National Laboratory, Richland, WA USA
- Joint BioEnergy Institute, Emeryville, CA USA
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32
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Holland P, Bergenholm D, Börlin CS, Liu G, Nielsen J. Predictive models of eukaryotic transcriptional regulation reveals changes in transcription factor roles and promoter usage between metabolic conditions. Nucleic Acids Res 2019; 47:4986-5000. [PMID: 30976803 PMCID: PMC6547448 DOI: 10.1093/nar/gkz253] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/26/2019] [Accepted: 04/04/2019] [Indexed: 01/08/2023] Open
Abstract
Transcription factors (TF) are central to transcriptional regulation, but they are often studied in relative isolation and without close control of the metabolic state of the cell. Here, we describe genome-wide binding (by ChIP-exo) of 15 yeast TFs in four chemostat conditions that cover a range of metabolic states. We integrate this data with transcriptomics and six additional recently mapped TFs to identify predictive models describing how TFs control gene expression in different metabolic conditions. Contributions by TFs to gene regulation are predicted to be mostly activating, additive and well approximated by assuming linear effects from TF binding signal. Notably, using TF binding peaks from peak finding algorithms gave distinctly worse predictions than simply summing the low-noise and high-resolution TF ChIP-exo reads on promoters. Finally, we discover indications of a novel functional role for three TFs; Gcn4, Ert1 and Sut1 during nitrogen limited aerobic fermentation. In only this condition, the three TFs have correlated binding to a large number of genes (enriched for glycolytic and translation processes) and a negative correlation to target gene transcript levels.
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Affiliation(s)
- Petter Holland
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg SE-41296, Sweden
| | - David Bergenholm
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg SE-41296, Sweden
| | - Christoph S Börlin
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg SE-41296, Sweden
| | - Guodong Liu
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg SE-41296, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg SE-41296, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Gothenburg SE-41296, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby DK-2800, Denmark
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Kim M, Park BG, Kim EJ, Kim J, Kim BG. In silico identification of metabolic engineering strategies for improved lipid production in Yarrowia lipolytica by genome-scale metabolic modeling. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:187. [PMID: 31367232 PMCID: PMC6657051 DOI: 10.1186/s13068-019-1518-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 07/03/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND Yarrowia lipolytica, an oleaginous yeast, is a promising platform strain for production of biofuels and oleochemicals as it can accumulate a high level of lipids in response to nitrogen limitation. Accordingly, many metabolic engineering efforts have been made to develop engineered strains of Y. lipolytica with higher lipid yields. Genome-scale model of metabolism (GEM) is a powerful tool for identifying novel genetic designs for metabolic engineering. Several GEMs for Y. lipolytica have recently been developed; however, not many applications of the GEMs have been reported for actual metabolic engineering of Y. lipolytica. The major obstacle impeding the application of Y. lipolytica GEMs is the lack of proper methods for predicting phenotypes of the cells in the nitrogen-limited condition, or more specifically in the stationary phase of a batch culture. RESULTS In this study, we showed that environmental version of minimization of metabolic adjustment (eMOMA) can be used for predicting metabolic flux distribution of Y. lipolytica under the nitrogen-limited condition and identifying metabolic engineering strategies to improve lipid production in Y. lipolytica. Several well-characterized overexpression targets, such as diglyceride acyltransferase, acetyl-CoA carboxylase, and stearoyl-CoA desaturase, were successfully rediscovered by our eMOMA-based design method, showing the relevance of prediction results. Interestingly, the eMOMA-based design method also suggested non-intuitive knockout targets, and we experimentally validated the prediction with a mutant lacking YALI0F30745g, one of the predicted targets involved in one-carbon/methionine metabolism. The mutant accumulated 45% more lipids compared to the wild-type. CONCLUSION This study demonstrated that eMOMA is a powerful computational method for understanding and engineering the metabolism of Y. lipolytica and potentially other oleaginous microorganisms.
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Affiliation(s)
- Minsuk Kim
- Institute of Engineering Research, Seoul National University, Seoul, 08826 Republic of Korea
- Present Address: Microbiome Program, Center for Individualized Medicine, Mayo Clinic, Rochester, MN 55905 USA
| | - Beom Gi Park
- School of Chemical and Biological Engineering, Seoul National University, Seoul, 08826 Republic of Korea
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826 Republic of Korea
| | - Eun-Jung Kim
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826 Republic of Korea
- Bio-MAX Institute, Seoul National University, Seoul, 08826 Republic of Korea
| | - Joonwon Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul, 08826 Republic of Korea
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826 Republic of Korea
| | - Byung-Gee Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul, 08826 Republic of Korea
- Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826 Republic of Korea
- Bio-MAX Institute, Seoul National University, Seoul, 08826 Republic of Korea
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Larroude M, Rossignol T, Nicaud JM, Ledesma-Amaro R. Synthetic biology tools for engineering Yarrowia lipolytica. Biotechnol Adv 2018; 36:2150-2164. [PMID: 30315870 PMCID: PMC6261845 DOI: 10.1016/j.biotechadv.2018.10.004] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 09/11/2018] [Accepted: 10/07/2018] [Indexed: 12/15/2022]
Abstract
The non-conventional oleaginous yeast Yarrowia lipolytica shows great industrial promise. It naturally produces certain compounds of interest but can also artificially generate non-native metabolites, thanks to an engineering process made possible by the significant expansion of a dedicated genetic toolbox. In this review, we present recently developed synthetic biology tools that facilitate the manipulation of Y. lipolytica, including 1) DNA assembly techniques, 2) DNA parts for constructing expression cassettes, 3) genome-editing techniques, and 4) computational tools.
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Affiliation(s)
- M Larroude
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - T Rossignol
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - J-M Nicaud
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - R Ledesma-Amaro
- Department of Bioengineering and Imperial College Centre for Synthetic Biology, Imperial College London, London, United Kingdom.
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He Q, Yang Y, Yang S, Donohoe BS, Van Wychen S, Zhang M, Himmel ME, Knoshaug EP. Oleaginicity of the yeast strain Saccharomyces cerevisiae D5A. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:258. [PMID: 30258492 PMCID: PMC6151946 DOI: 10.1186/s13068-018-1256-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 09/10/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND The model yeast, Saccharomyces cerevisiae, is not known to be oleaginous. However, an industrial wild-type strain, D5A, was shown to accumulate over 20% storage lipids from glucose when growth is nitrogen-limited compared to no more than 7% lipid accumulation without nitrogen stress. METHODS AND RESULTS To elucidate the mechanisms of S. cerevisiae D5A oleaginicity, we compared physiological and metabolic changes; as well as the transcriptional profiles of the oleaginous industrial strain, D5A, and a non-oleaginous laboratory strain, BY4741, under normal and nitrogen-limited conditions using analytic techniques and next-generation sequencing-based RNA-Seq transcriptomics. Transcriptional levels for genes associated with fatty acid biosynthesis, nitrogen metabolism, amino acid catabolism, as well as the pentose phosphate pathway and ethanol oxidation in central carbon (C) metabolism, were up-regulated in D5A during nitrogen deprivation. Despite increased carbon flux to lipids, most gene-encoding enzymes involved in triacylglycerol (TAG) assembly were expressed at similar levels regardless of the varying nitrogen concentrations in the growth media and strain backgrounds. Phospholipid turnover also contributed to TAG accumulation through increased precursor production with the down-regulation of subsequent phospholipid synthesis steps. Our results also demonstrated that nitrogen assimilation via the glutamate-glutamine pathway and amino acid metabolism, as well as the fluxes of carbon and reductants from central C metabolism, are integral to the general oleaginicity of D5A, which resulted in the enhanced lipid storage during nitrogen deprivation. CONCLUSION This work demonstrated the disequilibrium and rebalance of carbon and nitrogen contribution to the accumulation of lipids in the oleaginous yeast S. cerevisiae D5A. Rather than TAG assembly from acyl groups, the major switches for the enhanced lipid accumulation of D5A (i.e., fatty acid biosynthesis) are the increases of cytosolic pools of acetyl-CoA and NADPH, as well as alternative nitrogen assimilation.
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Affiliation(s)
- Qiaoning He
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Yongfu Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Shihui Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, 430062 China
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, 80401 USA
| | - Bryon S. Donohoe
- Biosciences Center, National Renewable Energy Laboratory, Golden, 80401 USA
| | | | - Min Zhang
- Biosciences Center, National Renewable Energy Laboratory, Golden, 80401 USA
| | - Michael E. Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, 80401 USA
| | - Eric P. Knoshaug
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, 80401 USA
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36
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Holistic Approaches in Lipid Production by Yarrowia lipolytica. Trends Biotechnol 2018; 36:1157-1170. [PMID: 30006239 DOI: 10.1016/j.tibtech.2018.06.007] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/11/2018] [Accepted: 06/18/2018] [Indexed: 01/01/2023]
Abstract
Concerns about climate change have driven research on the production of lipid-derived biofuels as an alternative and renewable liquid fuel source. Using oleaginous yeasts for lipid synthesis creates the potential for cost-effective industrial-scale operations due to their ability to reach high lipid titer, yield, and productivity resulting from their unique metabolism. Yarrowia lipolytica is the model oleaginous yeast, with the best-studied lipid metabolism, the greatest number of genetic tools, and a fully sequenced genome. In this review we highlight multiomics studies that elucidate the mechanisms allowing this yeast to achieve lipid overaccumulation and then present several major metabolic engineering efforts that enhanced the production metrics in Y. lipolytica. Recent achievements that applied novel engineering strategies are emphasized.
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Huang YY, Jian XX, Lv YB, Nian KQ, Gao Q, Chen J, Wei LJ, Hua Q. Enhanced squalene biosynthesis in Yarrowia lipolytica based on metabolically engineered acetyl-CoA metabolism. J Biotechnol 2018; 281:106-114. [PMID: 29986837 DOI: 10.1016/j.jbiotec.2018.07.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 06/28/2018] [Accepted: 07/01/2018] [Indexed: 12/13/2022]
Abstract
As a bioactive triterpenoid, squalene is widely used in the food industry, cosmetics, and pharmacology. Squalene's major commercial sources are the liver oil of deep-sea sharks and plant oils. In this study, we focused on the enhancement of squalene biosynthesis in Yarrowia lipolytica, with particular attention to the engineering of acetyl-CoA metabolism based on genome-scale metabolic reaction network analysis. Although the overexpression of the rate-limiting endogenous ylHMG1 (3-hydroxy-3-methylglutaryl-CoA reductase gene) could improve squalene synthesis by 3.2-fold over that by the control strain, the availability of the key intracellular precursor, acetyl-CoA, was found to play a more significant role in elevating squalene production. Analysis of metabolic networks with the newly constructed genome-scale metabolic model of Y. lipolytica iYL_2.0 showed that the acetyl-CoA pool size could be increased by redirecting carbon flux of pyruvate dehydrogenation towards the ligation of acetate and CoA or the cleavage of citrate to form oxaloacetate and acetyl-CoA. The overexpression of either acetyl-CoA synthetase gene from Salmonella enterica (acs*) or the endogenous ATP citrate lyase gene (ylACL1) resulted in a more than 50% increase in the cytosolic acetyl-CoA level. Moreover, iterative chromosomal integration of the ylHMG1, asc*, and ylACL1 genes resulted in a significant improvement in squalene production (16.4-fold increase in squalene content over that in the control strain). We also found that supplementation with 10 mM citrate in a flask culture further enhanced squalene production to 10 mg/g DCW. The information obtained in this study demonstrates that rationally engineering acetyl-CoA metabolism to ensure the supply of this key metabolic precursor is an efficient strategy for the enhancement of squalene biosynthesis.
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Affiliation(s)
- Yu-Ying Huang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China
| | - Xing-Xing Jian
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China
| | - Yu-Bei Lv
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China
| | - Ke-Qing Nian
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China
| | - Qi Gao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China
| | - Jun Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China
| | - Liu-Jing Wei
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China.
| | - Qiang Hua
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai, 200237, PR China
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38
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Nicora CD, Burnum-Johnson KE, Nakayasu ES, Casey CP, White RA, Roy Chowdhury T, Kyle JE, Kim YM, Smith RD, Metz TO, Jansson JK, Baker ES. The MPLEx Protocol for Multi-omic Analyses of Soil Samples. J Vis Exp 2018. [PMID: 29912205 DOI: 10.3791/57343] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Mass spectrometry (MS)-based integrated metaproteomic, metabolomic, and lipidomic (multi-omic) studies are transforming our ability to understand and characterize microbial communities in environmental and biological systems. These measurements are even enabling enhanced analyses of complex soil microbial communities, which are the most complex microbial systems known to date. Multi-omic analyses, however, do have sample preparation challenges, since separate extractions are typically needed for each omic study, thereby greatly amplifying the preparation time and amount of sample required. To address this limitation, a 3-in-1 method for the simultaneous extraction of metabolites, proteins, and lipids (MPLEx) from the same soil sample was created by adapting a solvent-based approach. This MPLEx protocol has proven to be both simple and robust for many sample types, even when utilized for limited quantities of complex soil samples. The MPLEx method also greatly enabled the rapid multi-omic measurements needed to gain a better understanding of the members of each microbial community, while evaluating the changes taking place upon biological and environmental perturbations.
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Affiliation(s)
- Carrie D Nicora
- Biological Sciences Division, Pacific Northwest National Laboratory
| | | | | | - Cameron P Casey
- Biological Sciences Division, Pacific Northwest National Laboratory
| | - Richard A White
- Biological Sciences Division, Pacific Northwest National Laboratory
| | | | - Jennifer E Kyle
- Biological Sciences Division, Pacific Northwest National Laboratory
| | - Young-Mo Kim
- Biological Sciences Division, Pacific Northwest National Laboratory
| | - Richard D Smith
- Biological Sciences Division, Pacific Northwest National Laboratory
| | - Thomas O Metz
- Biological Sciences Division, Pacific Northwest National Laboratory
| | - Janet K Jansson
- Biological Sciences Division, Pacific Northwest National Laboratory;
| | - Erin S Baker
- Biological Sciences Division, Pacific Northwest National Laboratory;
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Overexpression screen reveals transcription factors involved in lipid accumulation in Yarrowia lipolytica. FEMS Yeast Res 2018; 18:4956524. [DOI: 10.1093/femsyr/foy037] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 03/28/2018] [Indexed: 12/22/2022] Open
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40
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Can We Approach Theoretical Lipid Yields in Microalgae? Trends Biotechnol 2018; 36:265-276. [DOI: 10.1016/j.tibtech.2017.10.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 10/29/2017] [Accepted: 10/30/2017] [Indexed: 11/17/2022]
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41
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Yun EJ, Lee J, Kim DH, Kim J, Kim S, Jin YS, Kim KH. Metabolomic elucidation of the effects of media and carbon sources on fatty acid production by Yarrowia lipolytica. J Biotechnol 2018; 272-273:7-13. [PMID: 29499237 DOI: 10.1016/j.jbiotec.2018.02.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/16/2018] [Accepted: 02/27/2018] [Indexed: 12/17/2022]
Abstract
Lipid production by oleaginous Yarrowia lipolytica depends highly on culture environments, such as carbon sources, carbon/nitrogen (C/N) ratios, types of media, and cellular growth phases. In this study, the effects of media and carbon sources on lipid and metabolite production were investigated by profiling fatty acids and intracellular metabolites of Y. lipolytica grown in various media. The highest total fatty acid yield 114.04 ± 6.23 mg/g dry cell weight was achieved by Y. lipolytica grown in minimal medium with glycerol (SCG) in the exponential phase. The high lipid production by Y. lipolytica in SCG was presumed to be due to the higher C/N ratio in SCG than in the complex media. Moreover, glycerol promoted lipid production better than glucose in both complex and minimal media because glycerol can easily incorporate into the core of triglycerides. Metabolite profiling revealed that levels of long-chain fatty acids, such as stearic acid, palmitic acid, and arachidic acid, increased in SCG medium. Meanwhile, in complex media supplemented with either glucose or glycerol, levels of amino acids, such as cysteine, methionine, and glycine, highly increased. This metabolomic approach could be applied to modulate the global metabolic network of Y. lipolytica for producing lipids and other valuable products.
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Affiliation(s)
- Eun Ju Yun
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - James Lee
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Do Hyoung Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Jungyeon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Sooah Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Yong-Su Jin
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Kyoung Heon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
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42
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Current Knowledge and Recent Advances in Marine Dinoflagellate Transcriptomic Research. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2018. [DOI: 10.3390/jmse6010013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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43
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Wang Y, Zhang S, Zhu Z, Shen H, Lin X, Jin X, Jiao X, Zhao ZK. Systems analysis of phosphate-limitation-induced lipid accumulation by the oleaginous yeast Rhodosporidium toruloides. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:148. [PMID: 29849765 PMCID: PMC5968551 DOI: 10.1186/s13068-018-1134-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 04/28/2018] [Indexed: 05/12/2023]
Abstract
BACKGROUND Lipid accumulation by oleaginous microorganisms is of great scientific interest and biotechnological potential. While nitrogen limitation has been routinely employed, low-cost raw materials usually contain rich nitrogenous components, thus preventing from efficient lipid production. Inorganic phosphate (Pi) limitation has been found sufficient to promote conversion of sugars into lipids, yet the molecular basis of cellular response to Pi limitation and concurrent lipid accumulation remains elusive. RESULTS Here, we performed multi-omic analyses of the oleaginous yeast Rhodosporidium toruloides to shield lights on Pi-limitation-induced lipid accumulation. Samples were prepared under Pi-limited as well as Pi-repleted chemostat conditions, and subjected to analysis at the transcriptomic, proteomic, and metabolomic levels. In total, 7970 genes, 4212 proteins, and 123 metabolites were identified. Results showed that Pi limitation facilitates up-regulation of Pi-associated metabolism, RNA degradation, and triacylglycerol biosynthesis while down-regulation of ribosome biosynthesis and tricarboxylic acid cycle. Pi limitation leads to dephosphorylation of adenosine monophosphate and the allosteric activator of isocitrate dehydrogenase key to lipid biosynthesis. It was found that NADPH, the key cofactor for fatty acid biosynthesis, is limited due to reduced flux through the pentose phosphate pathway and transhydrogenation cycle and that this can be overcome by over-expression of an endogenous malic enzyme. These phenomena are found distinctive from those under nitrogen limitation. CONCLUSIONS Our data suggest that Pi limitation activates Pi-related metabolism, RNA degradation, and TAG biosynthesis while inhibits ribosome biosynthesis and TCA cycle, leading to enhanced carbon fluxes into lipids. The information greatly enriches our understanding on microbial oleaginicity and Pi-related metabolism. Importantly, systems data may facilitate designing advanced cell factories for production of lipids and related oleochemicals.
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Affiliation(s)
- Yanan Wang
- Division of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
| | - Sufang Zhang
- Division of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
| | - Zhiwei Zhu
- Division of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
| | - Hongwei Shen
- Division of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
| | - Xinping Lin
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034 People’s Republic of China
| | - Xiang Jin
- Beijing Bio-Fly Bioscience Co. Ltd., Beijing, 100080 People’s Republic of China
| | - Xiang Jiao
- Division of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
| | - Zongbao Kent Zhao
- Division of Biotechnology, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, CAS, 457 Zhongshan Road, Dalian, 116023 People’s Republic of China
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44
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Shi S, Zhao H. Metabolic Engineering of Oleaginous Yeasts for Production of Fuels and Chemicals. Front Microbiol 2017; 8:2185. [PMID: 29167664 PMCID: PMC5682390 DOI: 10.3389/fmicb.2017.02185] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 10/25/2017] [Indexed: 01/23/2023] Open
Abstract
Oleaginous yeasts have been increasingly explored for production of chemicals and fuels via metabolic engineering. Particularly, there is a growing interest in using oleaginous yeasts for the synthesis of lipid-related products due to their high lipogenesis capability, robustness, and ability to utilize a variety of substrates. Most of the metabolic engineering studies in oleaginous yeasts focused on Yarrowia that already has plenty of genetic engineering tools. However, recent advances in systems biology and synthetic biology have provided new strategies and tools to engineer those oleaginous yeasts that have naturally high lipid accumulation but lack genetic tools, such as Rhodosporidium, Trichosporon, and Lipomyces. This review highlights recent accomplishments in metabolic engineering of oleaginous yeasts and recent advances in the development of genetic engineering tools in oleaginous yeasts within the last 3 years.
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Affiliation(s)
- Shuobo Shi
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, China
- Metabolic Engineering Research Laboratory, Science and Engineering Institutes, Agency for Science, Technology and Research, Singapore, Singapore
| | - Huimin Zhao
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, China
- Metabolic Engineering Research Laboratory, Science and Engineering Institutes, Agency for Science, Technology and Research, Singapore, Singapore
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States
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Kamzolova SV, Morgunov IG. Metabolic peculiarities of the citric acid overproduction from glucose in yeasts Yarrowia lipolytica. BIORESOURCE TECHNOLOGY 2017; 243:433-440. [PMID: 28688326 DOI: 10.1016/j.biortech.2017.06.146] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/24/2017] [Accepted: 06/26/2017] [Indexed: 06/07/2023]
Abstract
Comparative study of 43 natural yeast strains belonging to 20 species for their capability for overproduction of citric acid (CA) from glucose under nitrogen limitation of cell growth was carried out. As a result, natural strain Yarrowia lipolytica VKM Y-2373 was selected. The effect of growth limitation by biogenic macroelements (nitrogen, phosphorus, or sulfur) on the CA production by the selected strain was studied. It was shown that yeasts Y. lipolytica grown under deficiency of nitrogen, phosphorus, or sulfur were able to excrete CA in industrially sufficient amounts (80-85g/L with the product yield (YCA) of 0.70-0.75g/g and the process selectivity of 92.5-95.3%). Based on the obtained data on activities of enzymes involved in the initial stages of glucose oxidation, the cycle of tricarboxylic acids, and the glyoxylate cycle, the conception of the mechanism responsible for the CA overproduction from glucose in Y. lipolytica was formulated.
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Affiliation(s)
- Svetlana V Kamzolova
- G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino 142290, Russia
| | - Igor G Morgunov
- G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino 142290, Russia.
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46
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Xie D. Integrating Cellular and Bioprocess Engineering in the Non-Conventional Yeast Yarrowia lipolytica for Biodiesel Production: A Review. Front Bioeng Biotechnol 2017; 5:65. [PMID: 29090211 PMCID: PMC5650997 DOI: 10.3389/fbioe.2017.00065] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/02/2017] [Indexed: 12/14/2022] Open
Abstract
As one of the major biofuels to replace fossil fuel, biodiesel has now attracted more and more attention due to its advantages in higher energy density and overall less greenhouse gas generation. Biodiesel (fatty acid alkyl esters) is produced by chemically or enzymatically catalyzed transesterification of lipids from microbial cells, microalgae, oil crops, or animal fats. Currently, plant oils or waste cooking oils/fats remain the major source for biodiesel production via enzymatic route, but the production capacity is limited either by the uncertain supplement of plant oils or by the low or inconsistent quality of waste oils/fats. In the past decades, significant progresses have been made on synthesis of microalgae oils directly from CO2via a photosynthesis process, but the production cost from any current technologies is still too high to be commercialized due to microalgae’s slow growth rate on CO2, inefficiency in photo-bioreactors, lack of efficient contamination control methods, and high cost in downstream recovery. At the same time, many oleaginous microorganisms have been studied to produce lipids via the fatty acid synthesis pathway under aerobic fermentation conditions, among them one of the most studied is the non-conventional yeast, Yarrowia lipolytica, which is able to produce fatty acids at very high titer, rate, and yield from various economical substrates. This review summarizes the recent research progresses in both cellular and bioprocess engineering in Y. lipolytica to produce lipids at a low cost that may lead to commercial-scale biodiesel production. Specific technologies include the strain engineering for using various substrates, metabolic engineering in high-yield lipid synthesis, cell morphology study for efficient substrate uptake and product formation, free fatty acid formation and secretion for improved downstream recovery, and fermentation engineering for higher productivities and less operating cost. To further improve the economics of the microbial oil-based biodiesel, production of lipid-related or -derived high-value products are also discussed.
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Affiliation(s)
- Dongming Xie
- Massachusetts Biomanufacturing Center, Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA, United States
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47
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Inference and interrogation of a coregulatory network in the context of lipid accumulation in Yarrowia lipolytica. NPJ Syst Biol Appl 2017; 3:21. [PMID: 28955503 PMCID: PMC5554221 DOI: 10.1038/s41540-017-0024-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/07/2017] [Accepted: 07/13/2017] [Indexed: 12/14/2022] Open
Abstract
Complex phenotypes, such as lipid accumulation, result from cooperativity between regulators and the integration of multiscale information. However, the elucidation of such regulatory programs by experimental approaches may be challenging, particularly in context-specific conditions. In particular, we know very little about the regulators of lipid accumulation in the oleaginous yeast of industrial interest Yarrowia lipolytica. This lack of knowledge limits the development of this yeast as an industrial platform, due to the time-consuming and costly laboratory efforts required to design strains with the desired phenotypes. In this study, we aimed to identify context-specific regulators and mechanisms, to guide explorations of the regulation of lipid accumulation in Y. lipolytica. Using gene regulatory network inference, and considering the expression of 6539 genes over 26 time points from GSE35447 for biolipid production and a list of 151 transcription factors, we reconstructed a gene regulatory network comprising 111 transcription factors, 4451 target genes and 17048 regulatory interactions (YL-GRN-1) supported by evidence of protein-protein interactions. This study, based on network interrogation and wet laboratory validation (a) highlights the relevance of our proposed measure, the transcription factors influence, for identifying phases corresponding to changes in physiological state without prior knowledge (b) suggests new potential regulators and drivers of lipid accumulation and
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Abstract
Increasing demand for plant oil for food, feed, and fuel production has led to food-fuel competition, higher plant lipid cost, and more need for agricultural land. On the other hand, the growing global production of biodiesel has increased the production of glycerol as a by-product. Efficient utilization of this by-product can reduce biodiesel production costs. We engineered Yarrowia lipolytica (Y. lipolytica) at various metabolic levels of lipid biosynthesis, degradation, and regulation for enhanced lipid and citric acid production. We used a one-step double gene knock-in and site-specific gene knock-out strategy. The resulting final strain combines the overexpression of homologous DGA1 and DGA2 in a POX-deleted background, and deletion of the SNF1 lipid regulator. This increased lipid and citric acid production in the strain under nitrogen-limiting conditions (C/N molar ratio of 60). The engineered strain constitutively accumulated lipid at a titer of more than 4.8 g/L with a lipid content of 53% of dry cell weight (DCW). The secreted citric acid reached a yield of 0.75 g/g (up to ~45 g/L) from pure glycerol in 3 days of batch fermentation using a 1-L bioreactor. This yeast cell factory was capable of simultaneous lipid accumulation and citric acid secretion. It can be used in fed-batch or continuous bioprocessing for citric acid recovery from the supernatant, along with lipid extraction from the harvested biomass.
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49
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Insights regarding fungal phosphoproteomic analysis. Fungal Genet Biol 2017; 104:38-44. [DOI: 10.1016/j.fgb.2017.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/27/2017] [Accepted: 03/07/2017] [Indexed: 11/19/2022]
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50
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Chen Y, Nielsen J. Flux control through protein phosphorylation in yeast. FEMS Yeast Res 2017; 16:fow096. [PMID: 27797916 DOI: 10.1093/femsyr/fow096] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2016] [Indexed: 01/26/2023] Open
Abstract
Protein phosphorylation is one of the most important mechanisms regulating metabolism as it can directly modify metabolic enzymes by the addition of phosphate groups. Attributed to such a rapid and reversible mechanism, cells can adjust metabolism rapidly in response to temporal changes. The yeast Saccharomyces cerevisiae, a widely used cell factory and model organism, is reported to show frequent phosphorylation events in metabolism. Studying protein phosphorylation in S. cerevisiae allows for gaining new insight into the function of regulatory networks, which may enable improved metabolic engineering as well as identify mechanisms underlying human metabolic diseases. Here we collect functional phosphorylation events of 41 enzymes involved in yeast metabolism and demonstrate functional mechanisms and the application of this information in metabolic engineering. From a systems biology perspective, we describe the development of phosphoproteomics in yeast as well as approaches to analysing the phosphoproteomics data. Finally, we focus on integrated analyses with other omics data sets and genome-scale metabolic models. Despite the advances, future studies improving both experimental technologies and computational approaches are imperative to expand the current knowledge of protein phosphorylation in S. cerevisiae.
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Affiliation(s)
- Yu Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.,Department of Biology and Biological Engineering, Chalmers University of Technology, SE412 96 Gothenburg, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE412 96 Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK2800 Kgs. Lyngby, Denmark
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