1
|
Lei Y, Wang X, Sun S, He B, Sun W, Wang K, Chen Z, Guo Z, Li Z. A review of lipid accumulation by oleaginous yeasts: Culture mode. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 919:170385. [PMID: 38364585 DOI: 10.1016/j.scitotenv.2024.170385] [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: 11/10/2023] [Revised: 01/05/2024] [Accepted: 01/21/2024] [Indexed: 02/18/2024]
Abstract
Microbial lipids have attracted considerable interest owing to their favorable environmental sustainability benefits. In laboratory-scale studies, the factors impacting lipid production in oleaginous yeasts, including culture conditions, nutrients, and low-cost substrates, have been extensively studied. However, there were several different modes of microbial lipid cultivation (batch culture, fed-batch culture, continuous culture, and other novel culture modes), making it difficult to comprehensively analyze impacting factors under different cultivation modes on a laboratory scale. And only few cases of microbial lipid production have been conducted at the pilot scale, which requires more technological reliability assessments and environmental benefit evaluations. Thus, this study summarized the different culture modes and cases of scale-up processes, highlighting the role of the nutrient element ratio in regulating culture mode selection and lipid accumulation. The cost distribution and environmental benefits of microbial lipid production by oleaginous yeasts were also investigated. Our results suggested that the continuous culture mode was recommended for the scale-up process because of its stable lipid accumulation. More importantly, exploring the continuous culture mode integrated with other efficient culture modes remained to be further investigated. In research on scale-up processes, low-cost substrate (organic waste) application and optimization of reactor operational parameters were key to increasing environmental benefits and reducing costs.
Collapse
Affiliation(s)
- Yuxin Lei
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China
| | - Xuemei Wang
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China.
| | - Shushuang Sun
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China.
| | - Bingyang He
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China
| | - Wenjin Sun
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China
| | - Kexin Wang
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China
| | - Zhengxian Chen
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China
| | - Zhiling Guo
- School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
| | - Zifu Li
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Xueyuan Road No.30, Haidian District, Beijing 100083, PR China.
| |
Collapse
|
2
|
Fan L, Guan G, Zhao J, Li D, Yu X, Shentu X. Comparative analysis of the diversity of symbionts in fat body of long- and short-winged brown planthoppers. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 115:e22096. [PMID: 38500448 DOI: 10.1002/arch.22096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/24/2024] [Accepted: 02/26/2024] [Indexed: 03/20/2024]
Abstract
The microbial community structure plays an important role in the internal environment of brown planthopper (BPH), Nilaparvata lugens (Hemiptera: Delphacidae), which is an indispensable part to reflect the internal environment of BPH. Wing dimorphism is a strategy for balancing flight and reproduction of insects. Here, quantitative fluorescence PCR was used to analyse the number and changes of the symbionts in the fat body of long- and short-winged BPHs at different developmental stages. A metagenomic library was constructed based on the 16 S rRNA sequence and internal transcribed spacer sequence for high-throughput sequencing, to analyze the community structure and population number of the symbionts of long- and short-winged BPHs, and to make functional prediction. This study enriches the connotation of BPH symbionts, and laid a theoretical foundation for the subsequent study of BPH-symbionts interaction and the function of symbionts in the host.
Collapse
Affiliation(s)
- Linlin Fan
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Science, China Jiliang University, Hangzhou, China
| | - Guangxiang Guan
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Science, China Jiliang University, Hangzhou, China
| | - Jingjing Zhao
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Science, China Jiliang University, Hangzhou, China
| | - Danting Li
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Science, China Jiliang University, Hangzhou, China
| | - Xiaoping Yu
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Science, China Jiliang University, Hangzhou, China
| | - Xuping Shentu
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Science, China Jiliang University, Hangzhou, China
| |
Collapse
|
3
|
Liu Y, Zhou W, Zhao M, Ma Q, Zhang J, Zhou W, Gong Z. Combination of alkaline biodiesel-derived crude glycerol pretreated corn stover with dilute acid pretreated water hyacinth for highly-efficient single cell oil production by oleaginous yeast Cutaneotrichosporon oleaginosum. BIORESOURCE TECHNOLOGY 2024; 395:130366. [PMID: 38266783 DOI: 10.1016/j.biortech.2024.130366] [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: 12/10/2023] [Revised: 01/07/2024] [Accepted: 01/20/2024] [Indexed: 01/26/2024]
Abstract
Single cell oil (SCO) prepared from biodiesel-derived crude glycerol (BCG) and lignocellulosic biomass (LCB) via oleaginous yeasts is an intriguing alternative precursor of biodiesel. Here, a novel strategy combining alkaline BCG pretreated corn stover and dilute acid pretreated water hyacinth for SCO overproduction was developed. The mixed pretreatment liquors (MPLs) were naturally neutralized and adjusted to a proper carbon-to-nitrogen ratio beneficial for SCO overproduction by Cutaneotrichosporon oleaginosum. The toxicity of inhibitors was relieved by dilution detoxification. The enzymatic hydrolysate of solid fractions was suitable for SCO production either separately or simultaneously with MPLs. Fed-batch fermentation of the MPLs resulted in high cell mass, SCO content, and SCO titer of 80.7 g/L, 75.7 %, and 61.1 g/L, respectively. The fatty acid profiles of SCOs implied high-quality biodiesel characteristics. This study offers a novel BCG&LCB-to-SCO route integrating BCG-based pretreatment and BCG/LCB hydrolysates co-utilization, which provides a cost-effective technical route for micro-biodiesel production.
Collapse
Affiliation(s)
- Yantao Liu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Wenting Zhou
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Man Zhao
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Qishuai Ma
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Junlu Zhang
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Wei Zhou
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Zhiwei Gong
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China; HuBei Province Key Laboratory of Coal Conversion and New Carbon Materials, Wuhan University of Science and Technology, Wuhan 430081, People's Republic of China.
| |
Collapse
|
4
|
Pham TA, Luu TH, Dam TH, To KA. Bioconversion of Shrimp Waste into Functional Lipid by a New Oleaginous Sakaguchia sp. Mol Biotechnol 2024:10.1007/s12033-023-01014-4. [PMID: 38198050 DOI: 10.1007/s12033-023-01014-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 11/27/2023] [Indexed: 01/11/2024]
Abstract
Chitin, the second most abundant biomolecule after cellulose in nature, is a significant aquaculture by-product, and is estimated at 6-8 million tons annually. Chitin is composed of monomeric N-acetylglucosamine (NAG) which can be seen as an alternative feedstock for biotechnology. Microbial functional lipids have gained attention due to their bioactivity and sustainable production. In this study, a new oleaginous yeast strain named Sakaguchia sp. HKC2 was found to be able to use NAG as the carbon source for growth and accumulate functional lipids such as PUFAs and carotenoids. When cultured on the NAG-containing medium, strain HKC2 exhibited slower growth and slower intracellular lipid accumulation compared to those on a glucose-containing medium. However, the lipids obtained from HKC2 grown on NAG medium were richer in PUFAs. Notably, torularhodin-a powerful bioactive carotenoid-was found in all HKC2 cultures on NAG, while torulene was abundant in glucose medium. These findings highlight a novel avenue for utilizing aquatic by-products and unlocking their potential.
Collapse
Affiliation(s)
- Tuan Anh Pham
- School of Biotechnology and Food Technology (SBFT), Hanoi University of Science and Technology (HUST), 1 Dai Co Viet, Hai Ba Trung, Hanoi, Vietnam.
- Laboratory of Applied Microbiology (LAM), Hanoi University of Science and Technology (HUST), 1 Dai Co Viet, Hai Ba Trung, Hanoi, Vietnam.
| | - Thi Huyen Luu
- School of Biotechnology and Food Technology (SBFT), Hanoi University of Science and Technology (HUST), 1 Dai Co Viet, Hai Ba Trung, Hanoi, Vietnam
| | - Thuy Hang Dam
- School of Biotechnology and Food Technology (SBFT), Hanoi University of Science and Technology (HUST), 1 Dai Co Viet, Hai Ba Trung, Hanoi, Vietnam
- Laboratory of Applied Microbiology (LAM), Hanoi University of Science and Technology (HUST), 1 Dai Co Viet, Hai Ba Trung, Hanoi, Vietnam
| | - Kim Anh To
- School of Biotechnology and Food Technology (SBFT), Hanoi University of Science and Technology (HUST), 1 Dai Co Viet, Hai Ba Trung, Hanoi, Vietnam
| |
Collapse
|
5
|
Xu C, Wang Y, Zhang C, Liu J, Fu H, Zhou W, Gong Z. Highly-efficient lipid production from hydrolysate of Radix paeoniae alba residue by oleaginous yeast Cutaneotrichosporon oleaginosum. BIORESOURCE TECHNOLOGY 2024; 391:129990. [PMID: 37931762 DOI: 10.1016/j.biortech.2023.129990] [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: 08/15/2023] [Revised: 10/24/2023] [Accepted: 11/03/2023] [Indexed: 11/08/2023]
Abstract
Valorization of herbal extraction residues (HERs) into value-added products is pivotal for the sustainability of Chinese medicine industry. Here, seven different enzymatic hydrolysates of dilute acid pretreated HERs were evaluated for lipid production by Cutaneotrichosporon oleaginosum. Among them, the highest sugar yield via hydrolysis and the maximum lipid production were obtained from Radix paeoniae alba residue (RPAR). More interestingly, high proportion of sugar polymers was disintegrated into fermentable sugars during the pretreatment step, allowing a cheap non-enzymatic route for producing sugars from RPAR. A repeated dilute acid pretreatment gained a high sugar concentration of 241.6 g/L through reusing the pretreatment liquor (PL) for four times. Biomass, lipid concentration, and lipid content achieved 49.5 g/L, 35.7 g/L and 72.2 %, respectively, using fed-batch culture of PL. The biodiesel parameters indicated lipids produced from HERs were suitable for biodiesel production. This study offers a cost-effective way to upgrade the HERs waste into micro-biodiesel.
Collapse
Affiliation(s)
- Chen Xu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Yanan Wang
- National Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, People's Republic of China
| | - Chuying Zhang
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Junheng Liu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Hanqi Fu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Wenting Zhou
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Zhiwei Gong
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China.
| |
Collapse
|
6
|
Zhang JX, Liu XL, Wang L, Fang Z. Two-stage process production of microbial lipid by co-fermentation of glucose and N-acetylglucosamine from food wastes with Cryptococcus curvatus. BIORESOURCE TECHNOLOGY 2023; 387:129685. [PMID: 37595808 DOI: 10.1016/j.biortech.2023.129685] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/12/2023] [Accepted: 08/14/2023] [Indexed: 08/20/2023]
Abstract
Microbial lipids were produced through a two-stage process with Cryptococcus curvatus by co-fermenting rice and shrimp shells hydrolysates. In the first stage, biomass production of glucose and N-acetylglucosamine was optimized by response surface methodology with the maximum biomass yield (17.60 g/L) under optimum conditions (43.2 g/L mixed sugar concentration, pH 5.8, 200 rpm, and 28 °C). In the second stage, according to a single-factor optimization setting (43.2 g/L sugar mixture solutions, pH 5.5, and shift time of 36 h), lipid titer of 10.08 g/L with content of 55.30 % was achieved. Scaling up to a 5-L bioreactor increased lipid content to 60.07 % with 0.233 g/g yield. When Cryptococcus curvatus was cultured in the blends of rice hydrolysates and shrimp shells hydrolysate, lipid content and yield were 52.25 % and 0.204 g/g. The fatty acid compositions of lipid were similar to those of typical vegetable oils.
Collapse
Affiliation(s)
- Jia-Xuan Zhang
- Biomass Group, College of Engineering, Nanjing Agricultural University, 40 Dianjiangtai Road, Nanjing, Jiangsu 210031, China
| | - Xiao-le Liu
- Biomass Group, College of Engineering, Nanjing Agricultural University, 40 Dianjiangtai Road, Nanjing, Jiangsu 210031, China
| | - Li Wang
- Biomass Group, College of Engineering, Nanjing Agricultural University, 40 Dianjiangtai Road, Nanjing, Jiangsu 210031, China
| | - Zhen Fang
- Biomass Group, College of Engineering, Nanjing Agricultural University, 40 Dianjiangtai Road, Nanjing, Jiangsu 210031, China.
| |
Collapse
|
7
|
Shaigani P, Fuchs T, Graban P, Prem S, Haack M, Masri M, Mehlmer N, Brueck T. Mastering targeted genome engineering of GC-rich oleaginous yeast for tailored plant oil alternatives for the food and chemical sector. Microb Cell Fact 2023; 22:25. [PMID: 36755261 PMCID: PMC9906925 DOI: 10.1186/s12934-023-02033-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 01/31/2023] [Indexed: 02/10/2023] Open
Abstract
BACKGROUND Sustainable production of triglycerides for various applications is a major focus of microbial factories. Oleaginous yeast species have been targeted for commercial production of microbial oils. Among all the oleaginous yeasts examined in a previous comparative study, Cutaneotrichosporon oleaginosus showed the highest lipid productivity. Moreover, a new lipid production process for C. oleaginosus with minimal waste generation and energy consumption resulted in the highest lipid productivity in the history of oleaginous yeasts. However, productivity and product diversity are restricted because of the genetic intractability of this yeast. To date, successful targeted genetic engineering of C. oleaginosus has not yet been reported. RESULTS The targeted gene editing was successfully carried out in C. oleaginosus using CRISPR/Cas system. A tailored enzyme system isolated to degrade the C. oleaginosus cell wall enabled the isolation of viable spheroplasts that are amenable to in-cell delivery of nucleic acids and proteins. The employment of both Cas9 protein and Cas mRNA was effective in obtaining strains with URA5 knockout that did not exhibit growth in the absence of uracil. Subsequently, we successfully created several strains with enhanced lipid yield (54% increase compared to that in wild type) or modified fatty acid profiles comparable with those of cocoa butter or sunflower oil compositions. CONCLUSION This study establishes the first targeted engineering technique for C. oleaginosus using the CRISPR/Cas system. The current study creates the foundation for flexible and targeted strain optimizations towards building a robust platform for sustainable microbial lipid production. Moreover, the genetic transformation of eukaryotic microbial cells using Cas9 mRNA was successfully achieved.
Collapse
Affiliation(s)
- Pariya Shaigani
- grid.6936.a0000000123222966Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Tobias Fuchs
- grid.6936.a0000000123222966Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Petra Graban
- grid.6936.a0000000123222966Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Sophia Prem
- grid.6936.a0000000123222966Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Martina Haack
- grid.6936.a0000000123222966Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Mahmoud Masri
- grid.6936.a0000000123222966Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany
| | - Norbert Mehlmer
- Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany.
| | - Thomas Brueck
- Department of Chemistry, Werner Siemens-Chair of Synthetic Biotechnology, Technical University of Munich, Garching, Germany.
| |
Collapse
|
8
|
Optimization of Pretreatment Conditions and Enzymatic Hydrolysis of Corn Cobs for Production of Microbial Lipids by Trichosporon oleaginosus. ENERGIES 2022. [DOI: 10.3390/en15093208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Microbial lipids produced from lignocellulosic biomass are sustainable alternative feedstock for biodiesel production. In this study, corn cobs were used as a carbon source for lipid production and growth of oleaginous yeast Trichosporon oleaginosus. Lignocellulosic biomass was subjected to alkali and acid pretreatment using sulfuric acid and sodium hydroxide under different temperatures, catalyst concentrations and treatment times. Pretreatment of corn cobs was followed by cellulase hydrolysis. Hydrolysis of alkali pretreated (2% NaOH at 50 °C for 6 h, 1% NaOH at 50 °C for 16 h, 2% NaOH at 121 °C for 1 h, 1% NaOH at 121 °C for 2 h) and acid pretreated (1% H2SO4 120 °C for 20 min, and 2% H2SO4 120 °C for 10 min) corn cobs resulted in more than 80% of the theoretical yield of glucose. The effect of substrate (5, 10, 15 and 20%, g g−1) and cellulase loading (15 and 30 Filter Paper Units per gram of glucan, FPU g−1) on fermentable sugar yield was also studied. The maximal glucose concentration of 81.64 g L−1 was obtained from alkali-pretreated corn cobs (2% NaOH at 50 °C for 6 h) at 20% substrate loading and 30 FPU of Cellic CTec2 g−1 of glucan. Enzymatic hydrolysates of pretreated biomasses and filtrates of lignocellulosic slurries obtained after pretreatment were used for growth and lipid synthesis by T. oleaginosus. The highest lipid concentration of 18.97 g L−1 was obtained on hydrolysate of alkali-pretreated corn cobs (with 1% NaOH at 50 °C for 16 h) using a 15% (g g−1) substrate loading and 15 FPU g−1 of cellulase loading. Significant lipid accumulation was also achieved using undetoxified filtrates of pretreated slurries as substrates. Results showed that pretreated corn cobs and undetoxified filtrates are suitable carbon sources for the growth and efficient accumulation of lipids in T. oleaginosus.
Collapse
|
9
|
Hu D, Wu H, Zhu Y, Zhang W, Mu W. Engineering Escherichia coli for highly efficient production of lacto-N-triose II from N-acetylglucosamine, the monomer of chitin. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:198. [PMID: 34625117 PMCID: PMC8501739 DOI: 10.1186/s13068-021-02050-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 09/29/2021] [Indexed: 05/05/2023]
Abstract
BACKGROUND Lacto-N-triose II (LNT II), an important backbone for the synthesis of different human milk oligosaccharides, such as lacto-N-neotetraose and lacto-N-tetraose, has recently received significant attention. The production of LNT II from renewable carbon sources has attracted worldwide attention from the perspective of sustainable development and green environmental protection. RESULTS In this study, we first constructed an engineered E. coli cell factory for producing LNT II from N-acetylglucosamine (GlcNAc) feedstock, a monomer of chitin, by introducing heterologous β-1,3-acetylglucosaminyltransferase, resulting in a LNT II titer of 0.12 g L-1. Then, lacZ (lactose hydrolysis) and nanE (GlcNAc-6-P epimerization to ManNAc-6-P) were inactivated to further strengthen the synthesis of LNT II, and the titer of LNT II was increased to 0.41 g L-1. To increase the supply of UDP-GlcNAc, a precursor of LNT II, related pathway enzymes including GlcNAc-6-P deacetylase, glucosamine synthase, and UDP-N-acetylglucosamine pyrophosphorylase, were overexpressed in combination, optimized, and modulated. Finally, a maximum titer of 15.8 g L-1 of LNT II was obtained in a 3-L bioreactor with optimal enzyme expression levels and β-lactose and GlcNAc feeding strategy. CONCLUSIONS Metabolic engineering of E. coli is an effective strategy for LNT II production from GlcNAc feedstock. The titer of LNT II could be significantly increased by modulating the gene expression strength and blocking the bypass pathway, providing a new utilization for GlcNAc to produce high value-added products.
Collapse
Affiliation(s)
- Duoduo Hu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Hao Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
| | - Yingying Zhu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, Jiangsu, China.
| |
Collapse
|
10
|
Zhou W, Wang Y, Zhang J, Zhao M, Tang M, Zhou W, Gong Z. A metabolic model of Lipomyces starkeyi for predicting lipogenesis potential from diverse low-cost substrates. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:148. [PMID: 34210354 PMCID: PMC8247262 DOI: 10.1186/s13068-021-01997-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 06/17/2021] [Indexed: 05/08/2023]
Abstract
BACKGROUND Lipomyces starkeyi has been widely regarded as a promising oleaginous yeast with broad industrial application prospects because of its wide substrate spectrum, good adaption to fermentation inhibitors, excellent fatty acid composition for high-quality biodiesel, and negligible lipid remobilization. However, the currently low experimental lipid yield of L. starkeyi prohibits its commercial success. Metabolic model is extremely valuable to comprehend the complex biochemical processes and provide great guidance for strain modification to facilitate the lipid biosynthesis. RESULTS A small-scale metabolic model of L. starkeyi NRRL Y-11557 was constructed based on the genome annotation information. The theoretical lipid yields of glucose, cellobiose, xylose, glycerol, and acetic acid were calculated according to the flux balance analysis (FBA). The optimal flux distribution of the lipid synthesis showed that pentose phosphate pathway (PPP) independently met the necessity of NADPH for lipid synthesis, resulting in the relatively low lipid yields. Several targets (NADP-dependent oxidoreductases) beneficial for oleaginicity of L. starkeyi with significantly higher theoretical lipid yields were compared and elucidated. The combined utilization of acetic acid and other carbon sources and a hypothetical reverse β-oxidation (RBO) pathway showed outstanding potential for improving the theoretical lipid yield. CONCLUSIONS The lipid biosynthesis potential of L. starkeyi can be significantly improved through appropriate modification of metabolic network, as well as combined utilization of carbon sources according to the metabolic model. The prediction and analysis provide valuable guidance to improve lipid production from various low-cost substrates.
Collapse
Affiliation(s)
- Wei Zhou
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan, 430081 People’s Republic of China
| | - Yanan Wang
- State Key Laboratory Breeding Base of Dao-Di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700 People’s Republic of China
| | - Junlu Zhang
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan, 430081 People’s Republic of China
| | - Man Zhao
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan, 430081 People’s Republic of China
| | - Mou Tang
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan, 430081 People’s Republic of China
| | - Wenting Zhou
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan, 430081 People’s Republic of China
- HuBei Province Key Laboratory of Coal Conversion and New Carbon Materials, Wuhan University of Science and Technology, Wuhan, 430081 People’s Republic of China
| | - Zhiwei Gong
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan, 430081 People’s Republic of China
- HuBei Province Key Laboratory of Coal Conversion and New Carbon Materials, Wuhan University of Science and Technology, Wuhan, 430081 People’s Republic of China
| |
Collapse
|