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Fortuin J, Hoffmeester LJ, Minnaar LS, den Haan R. Advancing cellulose utilization and engineering consolidated bioprocessing yeasts: current state and perspectives. Appl Microbiol Biotechnol 2025; 109:43. [PMID: 39939397 PMCID: PMC11821801 DOI: 10.1007/s00253-025-13426-0] [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: 12/12/2024] [Revised: 01/28/2025] [Accepted: 01/29/2025] [Indexed: 02/14/2025]
Abstract
Despite the lack of implementation of consolidated bioprocessing (CBP) at an industrial scale, this bioconversion strategy still holds significant potential as an economically viable solution for converting lignocellulosic biomass (LCB) into biofuels and green chemicals, provided an appropriate organism can be isolated or engineered. The use of Saccharomyces cerevisiae for this purpose requires, among other things, the development of a cellulase expression system within the yeast. Over the past three decades, numerous studies have reported the expression of cellulase-encoding genes, both individually and in combination, in S. cerevisiae. Various strategies have emerged to produce a core set of cellulases, with differing degrees of success. While one-step conversion of cellulosic substrates to ethanol has been reported, the resulting titers and productivities fall well below industrial requirements. In this review, we examine the strategies employed for cellulase expression in yeast, highlighting the successes in developing basic cellulolytic CBP-enabled yeasts. We also summarize recent advancements in rational strain design and engineering, exploring how these approaches can be further enhanced through modern synthetic biology tools to optimize CBP-enabled yeast strains for potential industrial applications. KEY POINTS: • S. cerevisiae's lack of cellulolytic ability warrants its engineering for industry. • Advancements in the expression of core sets of cellulases have been reported. • Rational engineering is needed to enhance cellulase secretion and strain robustness. • Insights gained from omics strategies will direct the future development of CBP strains.
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Affiliation(s)
- Jordan Fortuin
- Department of Biotechnology, University of the Western Cape, Bellville, South Africa
| | - Lazzlo J Hoffmeester
- Department of Biotechnology, University of the Western Cape, Bellville, South Africa
| | - Letitia S Minnaar
- Department of Biotechnology, University of the Western Cape, Bellville, South Africa
| | - Riaan den Haan
- Department of Biotechnology, University of the Western Cape, Bellville, South Africa.
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Zheng Y, Sun F, Liu S, Wang G, Chen H, Guo Y, Wang X, Escobar Bonora ML, Zhang S, Li Y, Chen G. Enhancing D-lactic acid production from non-detoxified corn stover hydrolysate via innovative F127-IEA hydrogel-mediated immobilization of Lactobacillus bulgaricus T15. Front Microbiol 2024; 15:1492127. [PMID: 39703712 PMCID: PMC11655503 DOI: 10.3389/fmicb.2024.1492127] [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: 09/06/2024] [Accepted: 11/11/2024] [Indexed: 12/21/2024] Open
Abstract
Background The production of D-lactic acid (D-LA) from non-detoxified corn stover hydrolysate is hindered by substrate-mediated inhibition and low cell utilization times. In this study, we developed a novel temperature-sensitive hydrogel, F127-IEA, for efficient D-LA production using a cell-recycle batch fermentation process. Results F127-IEA exhibited a porous structure with an average pore size of approximately 1 μm, facilitating the formation of stable Lactobacillus bulgaricus clusters within the gel matrix. It also maintains excellent mechanical properties. It also maintains excellent mechanical properties. F127-IEA immobilized Lactobacillus bulgaricus T15 (F127-IEA-T15) can be used in cell-recycle fermentation for over 150 days from glucose and 50 days from corn stover hydrolysate, achieving high production rates of D-LA from glucose (2.71 ± 0.85 g/L h) and corn stover hydrolysate (1.29 ± 0.39 g/L h). F127-IEA-T15 enhanced D-LA production by adsorbing and blocking toxic substances present in corn stover hydrolysate that are detrimental to cellular activity. Conclusions The newly developed hydrogels in this study provide a robust platform for large-scale extraction of D-LA from non-detoxified corn stover.
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Affiliation(s)
- Yuhan Zheng
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Feiyang Sun
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Siyi Liu
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Gang Wang
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Huan Chen
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Yongxin Guo
- Northeast Institute of Geography and Agroecology, University of Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Wetland Ecology and Environment, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
| | - Xiufeng Wang
- Biotechnology Research and Development Center, Vegetable and Flower Science Research Institute of Jilin Province, Changchun, China
| | - Maia Lia Escobar Bonora
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Sitong Zhang
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Yanli Li
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
| | - Guang Chen
- College of Life Science, Jilin Agricultural University, Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, Education Ministry of China, Changchun, Jilin, China
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Wang Y, Zhang Y, Cui Q, Feng Y, Xuan J. Composition of Lignocellulose Hydrolysate in Different Biorefinery Strategies: Nutrients and Inhibitors. Molecules 2024; 29:2275. [PMID: 38792135 PMCID: PMC11123716 DOI: 10.3390/molecules29102275] [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: 03/26/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024] Open
Abstract
The hydrolysis and biotransformation of lignocellulose, i.e., biorefinery, can provide human beings with biofuels, bio-based chemicals, and materials, and is an important technology to solve the fossil energy crisis and promote global sustainable development. Biorefinery involves steps such as pretreatment, saccharification, and fermentation, and researchers have developed a variety of biorefinery strategies to optimize the process and reduce process costs in recent years. Lignocellulosic hydrolysates are platforms that connect the saccharification process and downstream fermentation. The hydrolysate composition is closely related to biomass raw materials, the pretreatment process, and the choice of biorefining strategies, and provides not only nutrients but also possible inhibitors for downstream fermentation. In this review, we summarized the effects of each stage of lignocellulosic biorefinery on nutrients and possible inhibitors, analyzed the huge differences in nutrient retention and inhibitor generation among various biorefinery strategies, and emphasized that all steps in lignocellulose biorefinery need to be considered comprehensively to achieve maximum nutrient retention and optimal control of inhibitors at low cost, to provide a reference for the development of biomass energy and chemicals.
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Affiliation(s)
- Yilan Wang
- Department of Bioscience and Bioengineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Beijing 100083, China
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Synthetic Biology, Shandong Engineering Laboratory of Single Cell Oil, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
| | - Yuedong Zhang
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Synthetic Biology, Shandong Engineering Laboratory of Single Cell Oil, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
- Shandong Energy Institute, 189 Songling Road, Qingdao 266101, China
- Qingdao New Energy Shandong Laboratory, 189 Songling Road, Qingdao 266101, China
| | - Qiu Cui
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Synthetic Biology, Shandong Engineering Laboratory of Single Cell Oil, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Yingang Feng
- CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Synthetic Biology, Shandong Engineering Laboratory of Single Cell Oil, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
- Shandong Energy Institute, 189 Songling Road, Qingdao 266101, China
- Qingdao New Energy Shandong Laboratory, 189 Songling Road, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinsong Xuan
- Department of Bioscience and Bioengineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Beijing 100083, China
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van Dyk J, Görgens JF, van Rensburg E. Enhanced ethanol production from paper sludge waste under high-solids conditions with industrial and cellulase-producing strains of Saccharomyces cerevisiae. BIORESOURCE TECHNOLOGY 2024; 394:130163. [PMID: 38070577 DOI: 10.1016/j.biortech.2023.130163] [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: 09/15/2023] [Revised: 12/04/2023] [Accepted: 12/04/2023] [Indexed: 12/20/2023]
Abstract
Reported ethanol titres from hydrolysis-fermentation of the degraded fibres in paper sludge (PS) waste, generally obtained under fed-batch submerged conditions, can be improved through fermentation processes at high solids loadings, as demonstrated in the present study with two industrial PS wastes at enzyme dosages appropriate for solids loadings up to 40% (w/w). The industrial yeast,Saccharomyces cerevisiaestrain Ethanol Red®, was compared to two genetically engineeredS. cerevisiaestrains, namely Cellusec® 1.0 and Cellusec® 2.0, capable of xylose utilisation, and xylose utilisation and cellulase production, respectively. High-solids batch fermentations were conducted in 3 L horizontal rotating reactors and ethanol titres of 100.8 and 73.3 g/L were obtained for virgin pulp and corrugated recycle PS, respectively, at 40% (w/w) solids loading using Ethanol Red®. Xylose utilisation by Cellusec® 1.0 improved ethanol titres by up to 10.3%, while exogenous cellulolytic enzyme requirements were reduced by up to 50% using cellulase-producing Cellusec® 2.0.
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Affiliation(s)
- Janke van Dyk
- Dept. of Chemical Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| | - Johann F Görgens
- Dept. of Chemical Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| | - Eugéne van Rensburg
- Dept. of Chemical Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
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