1
|
Li J, Xia Y, Wei B, Shen W, Yang H, Chen X. Metabolic engineering of Candida tropicalis for efficient 1,2,4-butanetriol production. Biochem Biophys Res Commun 2024; 710:149876. [PMID: 38579537 DOI: 10.1016/j.bbrc.2024.149876] [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: 03/03/2024] [Accepted: 03/31/2024] [Indexed: 04/07/2024]
Abstract
1,2,4-Butanetriol serves as a precursor in the manufacture of diverse pharmaceuticals and the energetic plasticizer 1,2,4-butanetriol trinitrate. The study involved further modifications to an engineered Candida tropicalis strain, aimed at improving the production efficiency of 1,2,4-butanetriol. Faced with the issue of xylonate accumulation due to the low activity of heterologous xylonate dehydratase, we modulated iron metabolism at the transcriptional level to boost intracellular iron ion availability, thus enhancing the enzyme activity by 2.2-fold. Addressing the NADPH shortfall encountered during 1,2,4-butanetriol biosynthesis, we overexpressed pivotal genes in the NADPH regeneration pathway, achieving a 1,2,4-butanetriol yield of 3.2 g/L. The introduction of calcium carbonate to maintain pH balance led to an increased yield of 4 g/L, marking a 111% improvement over the baseline strain. Finally, the use of corncob hydrolysate as a substrate culminated in 1,2,4-butanetriol production of 3.42 g/L, thereby identifying a novel host for the conversion of corncob hydrolysate to 1,2,4-butanetriol.
Collapse
Affiliation(s)
- Jingyun Li
- Key Laboratory of Industrial Biotechnology, Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Yuanyuan Xia
- Key Laboratory of Industrial Biotechnology, Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Bo Wei
- Key Laboratory of Industrial Biotechnology, Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Wei Shen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Haiquan Yang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Xianzhong Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
| |
Collapse
|
2
|
Das S, Chandukishore T, Ulaganathan N, Dhodduraj K, Gorantla SS, Chandna T, Gupta LK, Sahoo A, Atheena PV, Raval R, Anjana PA, DasuVeeranki V, Prabhu AA. Sustainable biorefinery approach by utilizing xylose fraction of lignocellulosic biomass. Int J Biol Macromol 2024; 266:131290. [PMID: 38569993 DOI: 10.1016/j.ijbiomac.2024.131290] [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: 11/03/2023] [Revised: 03/20/2024] [Accepted: 03/29/2024] [Indexed: 04/05/2024]
Abstract
Lignocellulosic biomass (LCB) has been a lucrative feedstock for developing biochemical products due to its rich organic content, low carbon footprint and abundant accessibility. The recalcitrant nature of this feedstock is a foremost bottleneck. It needs suitable pretreatment techniques to achieve a high yield of sugar fractions such as glucose and xylose with low inhibitory components. Cellulosic sugars are commonly used for the bio-manufacturing process, and the xylose sugar, which is predominant in the hemicellulosic fraction, is rejected as most cell factories lack the five‑carbon metabolic pathways. In the present review, more emphasis was placed on the efficient pretreatment techniques developed for disintegrating LCB and enhancing xylose sugars. Further, the transformation of the xylose to value-added products through chemo-catalytic routes was highlighted. In addition, the review also recapitulates the sustainable production of biochemicals by native xylose assimilating microbes and engineering the metabolic pathway to ameliorate biomanufacturing using xylose as the sole carbon source. Overall, this review will give an edge on the bioprocessing of microbial metabolism for the efficient utilization of xylose in the LCB.
Collapse
Affiliation(s)
- Satwika Das
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - T Chandukishore
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Nivedhitha Ulaganathan
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Kawinharsun Dhodduraj
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Sai Susmita Gorantla
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Teena Chandna
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Laxmi Kumari Gupta
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Ansuman Sahoo
- Biochemical Engineering Laboratory, Department of Bioscience and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - P V Atheena
- Department of Biotechnology, Manipal Institute of Technology, Manipal 576104, Karnataka, India
| | - Ritu Raval
- Department of Biotechnology, Manipal Institute of Technology, Manipal 576104, Karnataka, India
| | - P A Anjana
- Department of Chemical Engineering, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Venkata DasuVeeranki
- Biochemical Engineering Laboratory, Department of Bioscience and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Ashish A Prabhu
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India.
| |
Collapse
|
3
|
Yuan D, Liu B, Jiang L, Chen Y, Xu G, Lin J, Yang L, Lian J, Jiang Y, Ye L, Wu M. XylR Overexpression in Escherichia coli Alleviated Transcriptional Repression by Arabinose and Enhanced Xylitol Bioproduction from Xylose Mother Liquor. Appl Biochem Biotechnol 2024:10.1007/s12010-024-04890-x. [PMID: 38393582 DOI: 10.1007/s12010-024-04890-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2024] [Indexed: 02/25/2024]
Abstract
Xylitol is a polyol widely used in food, pharmaceuticals, and light industries. It is currently produced through the chemical catalytic hydrogenation of xylose and generates xylose mother liquor as a substantial byproduct in the procedure of xylose extraction. If xylose mother liquor could also be efficiently bioconverted to xylitol, the greenness and atom economy of xylitol production would be largely improved. However, xylose mother liquor contains a mixture of glucose, xylose, and arabinose, raising the issue of carbon catabolic repression in its utilization by microbial conversion. Targeting this challenge, the transcriptional activator XylR was overexpressed in a previously constructed xylitol-producing E. coli strain CPH. The resulting strain CPHR produced 16.61 g/L of xylitol in shake-flask cultures from the mixture of corn cob hydrolysate and xylose mother liquor (1:1, v/v) with a xylose conversion rate of 90.1%, which were 2.23 and 2.15 times higher than the starting strain, respectively. Furthermore, XylR overexpression upregulated the expression levels of xylE, xylF, xylG, and xylH genes by 2.08-2.72 times in arabinose-containing medium, suggesting the alleviation of transcriptional repression of xylose transport genes by arabinose. This work lays the foundation for xylitol bioproduction from xylose mother liquor.
Collapse
Affiliation(s)
- Dongxu Yuan
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Bingbing Liu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Lin Jiang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Yuhuan Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Gang Xu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Jianping Lin
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Lirong Yang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Jiazhang Lian
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Yiqi Jiang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China.
- School of Biological and Chemical Engineering, NingboTech University, Ningbo, 315100, People's Republic of China.
| | - Lidan Ye
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China.
| | - Mianbin Wu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China.
- Ningbo Innovation Center, Zhejiang University, Ningbo, 315100, People's Republic of China.
- Zhejiang Key Laboratory of Antifungal Drugs, Taizhou, 318000, People's Republic of China.
| |
Collapse
|
4
|
Deng Z, Mu Y, Chen Z, Yan L, Ju X, Li L. Construction of a xylose metabolic pathway in Trichosporonoides oedocephalis ATCC 16958 for the production of erythritol and xylitol. Biotechnol Lett 2023; 45:1529-1539. [PMID: 37831286 DOI: 10.1007/s10529-023-03428-1] [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: 03/27/2023] [Revised: 05/18/2023] [Accepted: 07/15/2023] [Indexed: 10/14/2023]
Abstract
PURPOSE Erythritol is a valuable compound as sweetener and chemical material however cannot be fermented from the abundant substrate xylose. METHODS The strain Trichosporonoides oedocephalis ATCC 16958 was employed to produce polyols including xylitol and erythritol by metabolic engineering approaches. RESULTS The introduction of a substrate-specific ribose-5-phosphate isomerase endowed T. oedocephalis with xylose-assimilation activity to produce xylitol, and eliminated glycerol production simultaneously. A more value-added product, erythritol was produced by further introducing a homologous xylulose kinase. The carbon flux was redirected from xylitol to erythritol by adding high osmotic pressure. The production of erythritol was improved to 46.5 g/L in flasks by fermentation adjustment, and the process was scaled up in a 5-L fermentor, with a 40 g/L erythritol production after 120 h, and a time-space yield of 0.56 g/L/h. CONCLUSION This study demonstrated the potential of T. oedocephalis in the synthesis of multiple useful products from xylose.
Collapse
Affiliation(s)
- Zhou Deng
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No. 99 Xuefu Rd., Huqiu District, Suzhou, 215009, Jiangsu, People's Republic of China
| | - Yinghui Mu
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No. 99 Xuefu Rd., Huqiu District, Suzhou, 215009, Jiangsu, People's Republic of China
| | - Zhi Chen
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No. 99 Xuefu Rd., Huqiu District, Suzhou, 215009, Jiangsu, People's Republic of China
| | - Lishi Yan
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No. 99 Xuefu Rd., Huqiu District, Suzhou, 215009, Jiangsu, People's Republic of China
| | - Xin Ju
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No. 99 Xuefu Rd., Huqiu District, Suzhou, 215009, Jiangsu, People's Republic of China.
| | - Liangzhi Li
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No. 99 Xuefu Rd., Huqiu District, Suzhou, 215009, Jiangsu, People's Republic of China.
| |
Collapse
|
5
|
Singh AK, Deeba F, Kumar M, Kumari S, Wani SA, Paul T, Gaur NA. Development of engineered Candida tropicalis strain for efficient corncob-based xylitol-ethanol biorefinery. Microb Cell Fact 2023; 22:201. [PMID: 37803395 PMCID: PMC10557352 DOI: 10.1186/s12934-023-02190-3] [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: 08/02/2023] [Accepted: 08/30/2023] [Indexed: 10/08/2023] Open
Abstract
BACKGROUND Xylitol has a wide range of applications in the pharmaceuticals, cosmetic, food and beverage industry. Microbial xylitol production reduces the risk of contamination and is considered as environment friendly and sustainable compared to the chemical method. In this study, random mutagenesis and genetic engineering approaches were employed to develop Candida tropicalis strains with reduced xylitol dehydrogenase (XDH) activity to eliminate co-substrate requirement for corn cob-based xylitol-ethanol biorefinery. RESULTS The results suggest that when pure xylose (10% w/v) was fermented in bioreactor, the Ethyl methane sulfonate (EMS) mutated strain (C. tropicalis K2M) showed 9.2% and XYL2 heterozygous (XYL2/xyl2Δ::FRT) strain (C. tropicalis K21D) showed 16% improvement in xylitol production compared to parental strain (C. tropicalis K2). Furthermore, 1.5-fold improvement (88.62 g/L to 132 g/L) in xylitol production was achieved by C. tropicalis K21D after Response Surface Methodology (RSM) and one factor at a time (OFAT) applied for media component optimization. Finally, corncob hydrolysate was tested for xylitol production in biorefinery mode, which leads to the production of 32.6 g/L xylitol from hemicellulosic fraction, 32.0 g/L ethanol from cellulosic fraction and 13.0 g/L animal feed. CONCLUSIONS This work, for the first time, illustrates the potential of C. tropicalis K21D as a microbial cell factory for efficient production of xylitol and ethanol via an integrated biorefinery framework by utilising lignocellulosic biomass with minimum waste generation.
Collapse
Affiliation(s)
- Anup Kumar Singh
- Yeast Biofuel Group, DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Farha Deeba
- Yeast Biofuel Group, DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Mohit Kumar
- Yeast Biofuel Group, DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Sonam Kumari
- Yeast Biofuel Group, DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, 110067, India
- ICMR-National Institute of Pathology, New Delhi, 110029, India
| | - Shahid Ali Wani
- Yeast Biofuel Group, DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Tanushree Paul
- Yeast Biofuel Group, DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Naseem A Gaur
- Yeast Biofuel Group, DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi, 110067, India.
| |
Collapse
|
6
|
Liang P, Cao M, Li J, Wang Q, Dai Z. Expanding sugar alcohol industry: Microbial production of sugar alcohols and associated chemocatalytic derivatives. Biotechnol Adv 2023; 64:108105. [PMID: 36736865 DOI: 10.1016/j.biotechadv.2023.108105] [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: 08/27/2022] [Revised: 01/28/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023]
Abstract
Sugar alcohols are polyols that are widely employed in the production of chemicals, pharmaceuticals, and food products. Chemical synthesis of polyols, however, is complex and necessitates the use of hazardous compounds. Therefore, the use of microbes to produce polyols has been proposed as an alternative to traditional synthesis strategies. Many biotechnological approaches have been described to enhancing sugar alcohols production and microbe-mediated sugar alcohol production has the potential to benefit from the availability of inexpensive substrate inputs. Among of them, microbe-mediated erythritol production has been implemented in an industrial scale, but microbial growth and substrate conversion rates are often limited by harsh environmental conditions. In this review, we focused on xylitol, mannitol, sorbitol, and erythritol, the four representative sugar alcohols. The main metabolic engineering strategies, such as regulation of key genes and cofactor balancing, for improving the production of these sugar alcohols were reviewed. The feasible strategies to enhance the stress tolerance of chassis cells, especially thermotolerance, were also summarized. Different low-cost substrates like glycerol, molasses, cellulose hydrolysate, and CO2 employed for producing these sugar alcohols were presented. Given the value of polyols as precursor platform chemicals that can be leveraged to produce a diverse array of chemical products, we not only discuss the challenges encountered in the above parts, but also envisioned the development of their derivatives for broadening the application of sugar alcohols.
Collapse
Affiliation(s)
- Peixin Liang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin 300308, China
| | - Mingfeng Cao
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jing Li
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin 300308, China; College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Qinhong Wang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin 300308, China.
| | - Zongjie Dai
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin 300308, China.
| |
Collapse
|
7
|
Dasgupta D, Ahuja V, Singh R, More S, Mudliar S, Kumar M. Food-grade xylitol production from corncob biomass with acute oral toxicity studies. World J Microbiol Biotechnol 2023; 39:102. [PMID: 36797527 DOI: 10.1007/s11274-023-03542-2] [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: 11/30/2022] [Accepted: 02/05/2023] [Indexed: 02/18/2023]
Abstract
Xylitol, a sugar substitute, is widely used in various food formulations and finds a steady global market. In this study, xylitol crystals were produced from corncob by fermentation (as an alternative to the chemical catalytic process) by a GRAS yeast Pichia caribbica MTCC 5703 and characterized in detail for their purity and presence of any possible contaminant that may adversely affect mammalian cell growth and proliferation. The acute and chronic oral toxicity trials demonstrated no gross pathological changes with average weekly weight gain in female Wistar rats at high xylitol loading (LD50 > 10,000 mg/kg body weight). The clinical chemistry analysis supported the evidence of no dose-dependent effect by analyzing blood biochemical parameters. The finding suggests the possible application of the crystals (> 98% purity) as a food-grade ingredient for commercial manufacture pending human trials.
Collapse
Affiliation(s)
- Diptarka Dasgupta
- Biochemistry & Biotechnology Area, CSIR-Indian Institute of Petroleum (CSIR-IIP), Dehradun, Uttarakhand, 248005, India. .,Academy of Scientific & Industrial Research (AcSIR), CSIR-Indian Institute of Petroleum, Dehradun, Uttarakhand, 248005, India.
| | - Vishal Ahuja
- Biochemistry & Biotechnology Area, CSIR-Indian Institute of Petroleum (CSIR-IIP), Dehradun, Uttarakhand, 248005, India
| | - Raghuvir Singh
- Analytical Sciences Division, CSIR-Indian Institute of Petroleum, Dehradun, Uttarakhand, 248005, India
| | - Snehal More
- Biochemical Sciences Division, CSIR-National Chemical Laboratory (CSIR-NCL), Pune, Maharashtra, 411008, India
| | - Sandeep Mudliar
- Department Of Plant Cell Biotechnology, CSIR-Central Food Technology Research Institute, Mysore, 570001, India
| | - Madan Kumar
- Department of Biochemistry, CSIR-Central Food Technology Research Institute (CSIR-CFTRI), Mysore, 70001, India
| |
Collapse
|
8
|
Biological production of xylitol by using nonconventional microbial strains. World J Microbiol Biotechnol 2022; 38:249. [DOI: 10.1007/s11274-022-03437-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 10/07/2022] [Indexed: 10/31/2022]
|
9
|
Zhang L, Yang H, Xia Y, Shen W, Liu L, Li Q, Chen X. Engineering the oleaginous yeast Candida tropicalis for α-humulene overproduction. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:59. [PMID: 35619177 PMCID: PMC9137083 DOI: 10.1186/s13068-022-02160-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 05/17/2022] [Indexed: 11/10/2022]
Abstract
Abstract
Background
α-Humulene is a plant-derived monocyclic sesquiterpenoid with multiple pharmacological activities, and far-reaching potential for the development of new drugs. Currently, the production of α-humulene is typically achieved via plant extraction, which is not sustainable and limited by low yields. The oleaginous yeast Candida tropicalis has recently emerged as a valuable host for producing high-value-added chemicals. However, the potential of C. tropicalis for terpenoid production has not been exploited.
Results
In this study, C. tropicalis was engineered for de novo synthesis of α-humulene from glucose. To improve α-humulene production, the codon-optimised α-humulene synthase gene and the entire endogenous farnesyl diphosphate synthesis pathway were co-overexpressed. Furthermore, bottlenecks in the α-humulene synthase pathway were identified and relieved by overexpressing α-humulene synthase, acetoacetyl-CoA thiolase and NADH-dependent HMG-CoA reductase. Combined with fermentation medium optimisation, the engineered strain produced 195.31 mg/L of α-humulene in shake flasks and 4115.42 mg/L in a bioreactor through fed-batch fermentation, a 253- and 5345-fold increase over the initial production, respectively.
Conclusions
This study demonstrates the potential of C. tropicalis for α-humulene production, and presents a platform for the biosynthesis of other terpenoids.
Collapse
|
10
|
Xu Y, Wu Y, Liu Y, Li J, Du G, Chen J, Lv X, Liu L. Sustainable bioproduction of natural sugar substitutes: Strategies and challenges. Trends Food Sci Technol 2022. [DOI: 10.1016/j.tifs.2022.11.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
11
|
Li Y, Zhang L, Yang H, Xia Y, Liu L, Chen X, Shen W. Development of a gRNA Expression and Processing Platform for Efficient CRISPR-Cas9-Based Gene Editing and Gene Silencing in Candida tropicalis. Microbiol Spectr 2022; 10:e0005922. [PMID: 35543560 PMCID: PMC9241840 DOI: 10.1128/spectrum.00059-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/20/2022] [Indexed: 11/20/2022] Open
Abstract
Candida tropicalis, a nonmodel diploid microbe, has been applied in industry as a chassis cell. Metabolic engineering of C. tropicalis is challenging due to a lack of gene editing and regulation tools. Here, we report a tRNA:guide RNA (gRNA) platform for boosting gene editing and silencing efficiency in C. tropicalis. As the endogenous tRNA-processing system enables autocleavage for producing a large number of mature gRNAs, a tRNAGly sequence from the genome of C. tropicalis ATCC 20336 was selected for constructing the tRNA:gRNA platform. In the CRISPR-Cas9 system, the tRNA:gRNA platform proved to be efficient in single-gene and multi-gene editing. Furthermore, based on the tRNA:gRNA platform, a CRISPR interference (CRISPRi) system was developed to construct an efficient dCas9-mediated gene expression regulation system for C. tropicalis. The CRISPRi system was employed to regulate the expression of the exogenous gene GFP3 (green fluorescent protein) and the endogenous gene ADE2 (phosphoribosylaminoimidazole carboxylase). Different regions of GFP3 and ADE2 were targeted with the gRNAs processed by the tRNAGly, and the transcription levels of GFP3 and ADE2 were successfully downregulated to 23.9% ± 4.1% and 38.0% ± 7.4%, respectively. The effects of the target regions on gene regulation were also investigated. Additionally, the regulation system was applied to silence ERG9 (squalene synthase) to enhance β-carotene biosynthesis in a metabolically modified C. tropicalis strain. The results suggest that the endogenous tRNAGly and the CRISPRi system have great potential for metabolic engineering of C. tropicalis. IMPORTANCE In the nonmodel yeast Candida tropicalis, a lack of available RNA polymerase type III (Pol III) promoters hindered the development of guide RNA (gRNA) expression platforms for the establishment of CRISPR-Cas-mediated genome editing and silencing strategies. Here, a tRNA:gRNA platform was constructed. We show that this platform allows efficient and precise expression and processing of different gRNAs from a single polycistronic gene capable of mediating multi-gene editing in combination with CRISPR-Cas9. Furthermore, in combination with dCas9, the tRNA:gRNA platform was efficiently used for silencing of exogenous and endogenous genes, representing the first CRISPR interference tool (CRISPRi) in C. tropicalis. Importantly, the established CRISPRi-tRNA:gRNA tool was also used for metabolic engineering by regulating β-carotene biosynthesis in C. tropicalis. The results suggest that the tRNA:gRNA platform and the CRISPRi system will further advance the application of the CRISPR-Cas-based editing and CRISPRi systems for metabolic engineering in C. tropicalis.
Collapse
Affiliation(s)
- Yujie Li
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Lihua Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Haiquan Yang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Yuanyuan Xia
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Liming Liu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Xianzhong Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Wei Shen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| |
Collapse
|
12
|
Xylitol production by Pseudomonas gessardii VXlt-16 from sugarcane bagasse hydrolysate and cost analysis. Bioprocess Biosyst Eng 2022; 45:1019-1031. [PMID: 35355104 DOI: 10.1007/s00449-022-02721-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 03/13/2022] [Indexed: 12/28/2022]
Abstract
Xylitol is a well-known sugar alcohol with exponentially rising market demand due to its diverse industrial applications. Organic agro-industrial residues (OAIR) are economic alternative for the cost-effective production of commodity products along with addressing environmental pollution. The present study aimed to design a process for xylitol production from OAIR via microbial fermentation with Pseudomonas gessardii VXlt-16. Parametric analysis with Taguchi orthogonal array approach resulted in a conversion factor of 0.64 g xylitol/g xylose available in untreated sugarcane bagasse hydrolysate (SBH). At bench scale, the product yield increased to 71.98/100 g (0.66 g/L h). 48.49 g of xylitol crystals of high purity (94.56%) were recovered after detoxification with 2% activated carbon. Cost analysis identified downstream operations as one of the cost-intensive parts that can be countered by adsorbent recycling. Spent carbon, regenerated with acetic acid washing can be reused for six cycles effectively and reduced downstream cost by about ≈32%. The strategy would become useful in the cost-effective production of several biomass-dependent products like proteins, enzymes, organic acids, as well.
Collapse
|
13
|
Erian AM, Sauer M. Utilizing yeasts for the conversion of renewable feedstocks to sugar alcohols - a review. BIORESOURCE TECHNOLOGY 2022; 346:126296. [PMID: 34798255 DOI: 10.1016/j.biortech.2021.126296] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/30/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
Sugar alcohols are widely marketed compounds. They are useful building block chemicals and of particular value as low- or non-calorigenic sweeteners, serving as sugar substitutes in the food industry. To date most sugar alcohols are produced by chemical routes using pure sugars, but a transition towards the use of renewable, non-edible feedstocks is anticipated. Several yeasts are naturally able to convert renewable feedstocks, such as lignocellulosic substrates, glycerol and molasses, into sugar alcohols. These bioconversions often face difficulties to obtain sufficiently high yields and productivities necessary for industrialization. This review provides insight into the most recent studies on utilizing yeasts for the conversion of renewable feedstocks to diverse sugar alcohols, including xylitol, erythritol, mannitol and arabitol. Moreover, metabolic approaches are highlighted that specifically target shortcomings of sugar alcohol production by yeasts from these renewable substrates.
Collapse
Affiliation(s)
- Anna Maria Erian
- CD-Laboratory for Biotechnology of Glycerol, Muthgasse 18, Vienna, Austria; University of Natural Resources and Life Sciences, Vienna, Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, Muthgasse 18, 1190 Vienna, Austria
| | - Michael Sauer
- CD-Laboratory for Biotechnology of Glycerol, Muthgasse 18, Vienna, Austria; University of Natural Resources and Life Sciences, Vienna, Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, Muthgasse 18, 1190 Vienna, Austria.
| |
Collapse
|
14
|
Lekshmi Sundar MS, Madhavan Nampoothiri K. An overview of the metabolically engineered strains and innovative processes used for the value addition of biomass derived xylose to xylitol and xylonic acid. BIORESOURCE TECHNOLOGY 2022; 345:126548. [PMID: 34906704 DOI: 10.1016/j.biortech.2021.126548] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
Xylose, the most abundant pentose sugar of the hemicellulosic fraction of lignocellulosic biomass, has to be utilized rationally for the commercial viability of biorefineries. An effective pre-treatment strategy for the release of xylose from the biomass and an appropriate microbe of the status of an Industrial strain for the utilization of this pentose sugar are key challenges which need special attention for the economic success of the biomass value addition to chemicals. Xylitol and xylonic acid, the alcohol and acid derivatives of xylose are highly demanded commodity chemicals globally with plenty of applications in the food and pharma industries. This review emphasis on the natural and metabolically engineered strains utilizing xylose and the progressive and innovative fermentation strategies for the production and subsequent recovery of the above said chemicals from pre-treated biomass medium.
Collapse
Affiliation(s)
- M S Lekshmi Sundar
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Thiruvananthapuram 695019, Kerala, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDG Campus, Ghaziabad, Uttar Pradesh 201002, India
| | - K Madhavan Nampoothiri
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Thiruvananthapuram 695019, Kerala, India.
| |
Collapse
|