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Li J, Chen H, Chang L, Wu C, Zhang H, Chen YQ, Chen W. Functions and substrate selectivity of diacylglycerol acyltransferases from Mortierella alpina. Appl Microbiol Biotechnol 2023; 107:5761-5774. [PMID: 37498333 DOI: 10.1007/s00253-023-12694-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 07/07/2023] [Accepted: 07/18/2023] [Indexed: 07/28/2023]
Abstract
Mortierella alpina produces various polyunsaturated fatty acids in the form of triacylglycerols (TAG). Diacylglycerol acyltransferase (DGAT) catalyzes the binding of acyl-CoA to diacylglycerol to form TAG and is the key enzyme involved in TAG synthesis. A variety of DGATs are present in M. alpina; however, comparative analysis of the functional properties and substrate selectivity of these DGATs is insufficient. In this study, DGAT1 (MaDGAT1A/1B/1C) and DGAT2 (MaDGAT2A/2B) isoforms from M. alpina were analyzed and heterologously expressed in S. cerevisiae H1246. The results showed that MaDGAT1A/1B/2A/2B were able to restore TAG synthesis, and the corresponding TAG content in recombinant yeasts was 2.92 ± 0.42%, 3.62 ± 0.22%, 0.86 ± 0.34%, and 0.18 ± 0.09%, respectively. In S. cerevisiae H1246, MaDGAT1A preferred C16:1 among monounsaturated fatty acids, MaDGAT1B preferred C16:0 among saturated fatty acids (SFAs), and MaDGAT2A/2B preferred C18:0 among SFAs. Under exogenous addition of polyunsaturated fatty acids (PUFAs), MaDGAT1A and 2A preferentially assembled linoleic acid into TAG, and MaDGAT2B had substrate selectivity for eicosapentaenoic and linoleic acids in ω-6 PUFAs. In vitro, MaDGAT1A showed no obvious acyl-CoA selectivity and MaDGAT1B preferred C20:5-CoA. MaDGAT1A/1B preferred C18:1/C18:1-DAG compared with C20:4/C20:4-DAG. This study indicates that MaDGATs have the potential to be used in the production of LA/EPA-rich TAG and provide a reference for improving the production of TAGs in oleaginous fungi. KEY POINTS: • MaDGAT1A preferred C16:1 among MUFAs, MaDGAT1B and MaDGAT2A/2B preferred C16:0 and C18:0 among SFAs, respectively • MaDGAT1A/2A preferentially assembled linoleic acid into TAG, and MaDGAT2B has substrate selectivity for eicosapentaenoic acid and linoleic acid in ω-6 PUFAs • MaDGAT1A showed no obvious acyl-CoA selectivity, and MaDGAT1B preferred C20:5-CoA. MaDGAT1A/1B preferred to select C18:1/C18:1-DAG compared with C20:4/C20:4-DAG.
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Affiliation(s)
- Jun Li
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
| | - Haiqin Chen
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China.
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China.
| | - Lulu Chang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
| | - Chen Wu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
| | - Hao Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
| | - Yong Q Chen
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC, 27157, USA
| | - Wei Chen
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, 214122, People's Republic of China
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Yu R, Chang L, Cao J, Yang B, Chen H, Chen W. Applications of Diacylglycerol Acyltransferase for Triacylglycerol Production in Mortierella alpina. J Fungi (Basel) 2023; 9:jof9020219. [PMID: 36836332 PMCID: PMC9965251 DOI: 10.3390/jof9020219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/01/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023] Open
Abstract
Triacylglycerol (TG) with high-value long-chain polyunsaturated fatty acids is beneficial to human health; consequently, there is an urgent need to broaden its sources due to the current growing demand. Mortierella alpina, one of the most representative oleaginous fungi, is the only certificated source of dietary arachidonic acid-rich oil supplied in infant formula. This study was conducted to improve TG production in M. alpina by homologous overexpression of diacylglycerol acyltransferase (DGAT) and linseed oil (LSO) supplementation. Our results showed that the homologous overexpression of MaDGAT1B and MaDGAT2A strengthened TG biosynthesis and significantly increased the TG content compared to the wild-type by 12.24% and 14.63%, respectively. The supplementation with an LSO concentration of 0.5 g/L elevated the TG content to 83.74% and total lipid yield to 4.26 ± 0.38 g/L in the M. alpina-MaDGAT2A overexpression strain. Our findings provide an effective strategy for enhancing TG production and highlight the role of DGAT in TG biosynthesis in M. alpina.
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Affiliation(s)
- Ruilin Yu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Lulu Chang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Jun Cao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Bo Yang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Haiqin Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Correspondence:
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi 214122, China
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3
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Chen G, Harwood JL, Lemieux MJ, Stone SJ, Weselake RJ. Acyl-CoA:diacylglycerol acyltransferase: Properties, physiological roles, metabolic engineering and intentional control. Prog Lipid Res 2022; 88:101181. [PMID: 35820474 DOI: 10.1016/j.plipres.2022.101181] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/31/2022] [Accepted: 07/04/2022] [Indexed: 12/15/2022]
Abstract
Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) catalyzes the last reaction in the acyl-CoA-dependent biosynthesis of triacylglycerol (TAG). DGAT activity resides mainly in membrane-bound DGAT1 and DGAT2 in eukaryotes and bifunctional wax ester synthase-diacylglycerol acyltransferase (WSD) in bacteria, which are all membrane-bound proteins but exhibit no sequence homology to each other. Recent studies also identified other DGAT enzymes such as the soluble DGAT3 and diacylglycerol acetyltransferase (EaDAcT), as well as enzymes with DGAT activities including defective in cuticular ridges (DCR) and steryl and phytyl ester synthases (PESs). This review comprehensively discusses research advances on DGATs in prokaryotes and eukaryotes with a focus on their biochemical properties, physiological roles, and biotechnological and therapeutic applications. The review begins with a discussion of DGAT assay methods, followed by a systematic discussion of TAG biosynthesis and the properties and physiological role of DGATs. Thereafter, the review discusses the three-dimensional structure and insights into mechanism of action of human DGAT1, and the modeled DGAT1 from Brassica napus. The review then examines metabolic engineering strategies involving manipulation of DGAT, followed by a discussion of its therapeutic applications. DGAT in relation to improvement of livestock traits is also discussed along with DGATs in various other eukaryotic organisms.
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Affiliation(s)
- Guanqun Chen
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada.
| | - John L Harwood
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - M Joanne Lemieux
- Department of Biochemistry, University of Alberta, Membrane Protein Disease Research Group, Edmonton T6G 2H7, Canada
| | - Scot J Stone
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
| | - Randall J Weselake
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada
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Li J, Cao J, Chen H, Tang X, Zhang H, Chen W. Functional characterization of two diacylglycerol acyltransferase 1 genes in Mortierella alpina. Lett Appl Microbiol 2021; 74:194-203. [PMID: 34755357 DOI: 10.1111/lam.13597] [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: 09/17/2021] [Revised: 11/02/2021] [Accepted: 11/05/2021] [Indexed: 11/30/2022]
Abstract
Diacylglycerol acyltransferase (DGAT) is a crucial enzyme in the triacylglycerol (TAG) biosynthesis pathway. The oleaginous fungus Mortierella alpina can accumulate large amounts of arachidonic acid (ARA, C20:4) in the form of TAG. Therefore, it is important to study the functional characteristics of its DGAT. Two putative genes MaDGAT1A/1B encoding DGAT1 were identified in M. alpina ATCC 32222 genome by sequence alignment. Sequence alignment with identified DGAT1 homologs showed that MaDGAT1A/1B contain seven conserved motifs that are characteristic of the DGAT1 subfamily. Conserved domain analysis showed that both MaDGAT1A and MaDGAT1B belong to the Membrane-bound O-acyltransferases superfamily. The transforming with MaDGAT1A/1B genes could increase the accumulation of TAG in Saccharomyces cerevisiae to 4·47 and 7·48% of dry cell weight, which was 7·3-fold and 12·3-fold of the control group, respectively, but has no effect on the proportion of fatty acids in TAG. This study showed that MaDGAT1A/1B could effectively promote the accumulation of TAG and therefore may be used in metabolic engineering aimed to increase TAG production of oleaginous fungi.
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Affiliation(s)
- J Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, P.R. China
| | - J Cao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, P.R. China
| | - H Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, P.R. China
| | - X Tang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, P.R. China
| | - H Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, P.R. China.,Wuxi Translational Medicine Research Center and Jiangsu Translational Medicine Research Institute Wuxi Branch, Wuxi, P.R. China
| | - W Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, P.R. China
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Chang L, Lu H, Chen H, Tang X, Zhao J, Zhang H, Chen YQ, Chen W. Lipid metabolism research in oleaginous fungus Mortierella alpina: Current progress and future prospects. Biotechnol Adv 2021; 54:107794. [PMID: 34245810 DOI: 10.1016/j.biotechadv.2021.107794] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 06/11/2021] [Accepted: 07/04/2021] [Indexed: 12/19/2022]
Abstract
The oleaginous fungus Mortierella alpina has distinct advantages in long-chain PUFAs production, and it is the only source for dietary arachidonic acid (ARA) certificated by FDA and European Commission. This review provides an overall introduction to M. alpina, including its major research methods, key factors governing lipid biosynthesis, metabolic engineering and omics studies. Currently, the research interests in M. alpina focus on improving lipid yield and fatty acid desaturation degree by enhancing fatty acid precursors and the reducing power NADPH, and genetic manipulation on PUFAs synthetic pathways is carried to optimise fatty acid composition. Besides, multi-omics studies have been applied to elucidate the global regulatory mechanism of lipogenesis in M. alpina. However, research challenges towards achieving a lipid cell factory lie in strain breeding and cost control due to the coenocytic mycelium, long fermentation period and insufficient conversion rate from carbon to lipid. We also proposed future research goals based on a multilevel regulating strategy: obtaining ideal chassis by directional evolution and high-throughput screening; rewiring central carbon metabolism and inhibiting competitive pathways by multi-gene manipulation system to enhance carbon to lipid conversion rate; optimisation of protein function based on post-translational modification; application of dynamic fermentation strategies suitable for different fermentation phases. By reviewing the comprehensive research progress of this oleaginous fungus, we aim to further comprehend the fungal lipid metabolism and provide reference information and guidelines for the exploration of microbial oils from the perspectives of fundamental research to industrial application.
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Affiliation(s)
- Lulu Chang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
| | - Hengqian Lu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
| | - Haiqin Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
| | - Xin Tang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
| | - Jianxin Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
| | - Yong Q Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu 214122, PR China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, PR China; Wuxi Translational Medicine Research Center, Jiangsu Translational Medicine Research Institute Wuxi Branch, Wuxi, Jiangsu 214122, PR China; Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu 214122, PR China.
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Lu H, Chen H, Tang X, Yang Q, Zhang H, Chen YQ, Chen W. Ultra Performance Liquid Chromatography-Q Exactive Orbitrap/Mass Spectrometry-Based Lipidomics Reveals the Influence of Nitrogen Sources on Lipid Biosynthesis of Mortierella alpina. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:10984-10993. [PMID: 31525294 DOI: 10.1021/acs.jafc.9b04455] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The objective of the present study was to reveal the effects of four types of nitrogen sources (soymeal, yeast extract, KNO3, and ammonium tartrate) on the lipid metabolism of the oleaginous fungus Mortierella alpina using untargeted lipidomics, targeted fatty acid, and reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis. Our results showed clear differences in the contents and compositions of lipids between four types of nitrogen sources. Soymeal and ammonium tartrate supplementation favored the accumulation of triglycerides with arachidonic acid (ARA) and C16-18 fatty acids, respectively. These results were further validated by our targeted fatty acid analysis. RT-qPCR analysis of related genes in M. alpina between the four nitrogen source conditions found that soymeal supplementation dramatically increased the expression of GPAT, ELOVL, and Δ12/Δ6 desaturase. Our findings provided new insights into the regulation of lipid biosynthesis in M. alpina and potential avenues for genetic manipulation and highlighted the importance of an optimal nitrogen source for ARA-rich oil production.
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Affiliation(s)
| | - Haiqin Chen
- (Yangzhou) Institute of Food Biotechnology , Jiangnan University , Yangzhou , Jiangsu 225004 , People's Republic of China
| | | | | | - Hao Zhang
- (Yangzhou) Institute of Food Biotechnology , Jiangnan University , Yangzhou , Jiangsu 225004 , People's Republic of China
| | | | - Wei Chen
- Beijing Innovation Centre of Food Nutrition and Human Health , Beijing Technology and Business University (BTBU) , Beijing 100048 , People's Republic of China
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Jeennor S, Anantayanon J, Panchanawaporn S, Khoomrung S, Chutrakul C, Laoteng K. Reengineering lipid biosynthetic pathways of Aspergillus oryzae for enhanced production of γ-linolenic acid and dihomo-γ-linolenic acid. Gene 2019; 706:106-114. [DOI: 10.1016/j.gene.2019.04.074] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/18/2019] [Accepted: 04/26/2019] [Indexed: 01/14/2023]
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Dissecting metabolic behavior of lipid over-producing strain of Mucor circinelloides through genome-scale metabolic network and multi-level data integration. Gene 2018; 670:87-97. [PMID: 29800733 DOI: 10.1016/j.gene.2018.05.085] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 05/14/2018] [Accepted: 05/21/2018] [Indexed: 12/19/2022]
Abstract
Lipid accumulation is an important cellular process of oleaginous microorganisms. To dissect metabolic behavior of oleaginous Zygomycetes, the lipid over-producing strain, Mucor circinelloides WJ11, was subjected for omics-scale analysis. The genome annotation was improved and used for construction of genome-scale metabolic network of WJ11 strain. Then, the quality of the metabolic network was enhanced by incorporating gene and protein expression data. In addition to the known oleaginous genes, our results showed a number of newly identified unique genes of WJ11 strain, which involved in central carbon metabolism, lipid, amino acid and nitrogen metabolisms. The systematic compilations indicated the additional metabolic routes with the involvement in supplying precursors (acetyl-CoA, NADPH and fatty acyl substrate) for fatty acid and lipid biosynthesis. Interestingly, amino acid metabolism played a substantial role in responsive mechanism of the fungal cells to nutrient imbalance circumstance through lipogenesis as the finding of reporter metabolites (l-methionine, l-glutamate, l-aspartate, l-asparagine and l-glutamine) at lipid-accumulating stage. The cooperative function of certain lipid-degrading enzymes at the particular growth stage was elucidated by integrating the metabolic networks with gene expression data. The unique feature of carotenoid biosynthetic route in WJ11 strain was also identified by protein domain analysis. Taken together, there were cross-functional metabolisms in regulating lipid biosynthesis and retaining high level of cellular lipids in the representative of lipid over-producing strains.
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