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Mazzoli R, Pescarolo S, Gilli G, Gilardi G, Valetti F. Hydrogen production pathways in Clostridia and their improvement by metabolic engineering. Biotechnol Adv 2024; 73:108379. [PMID: 38754796 DOI: 10.1016/j.biotechadv.2024.108379] [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: 12/04/2023] [Revised: 05/13/2024] [Accepted: 05/13/2024] [Indexed: 05/18/2024]
Abstract
Biological production of hydrogen has a tremendous potential as an environmentally sustainable technology to generate a clean fuel. Among the different available methods to produce biohydrogen, dark fermentation features the highest productivity and can be used as a means to dispose of organic waste biomass. Within this approach, Clostridia have the highest theoretical H2 production yield. Nonetheless, most strains show actual yields far lower than the theoretical maximum: improving their efficiency becomes necessary for achieving cost-effective fermentation processes. This review aims at providing a survey of the metabolic network involved in H2 generation in Clostridia and strategies used to improve it through metabolic engineering. Together with current achievements, a number of future perspectives to implement these results will be illustrated.
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Affiliation(s)
- Roberto Mazzoli
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Torino, Via Accademia Albertina 13, 10123 Torino, Italy.
| | - Simone Pescarolo
- Biology applied to the environment, Laboratories of microbiology and ecotoxicology, Ecobioqual, Environment Park. Via Livorno 60, 10144 Torino, Italy
| | - Giorgio Gilli
- Department of Sciences of Public Health and Pediatrics, School of Medicine, University of Torino, Via Santena 5 bis, 10126 Torino, Italy
| | - Gianfranco Gilardi
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Torino, Via Accademia Albertina 13, 10123 Torino, Italy
| | - Francesca Valetti
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Torino, Via Accademia Albertina 13, 10123 Torino, Italy.
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2
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Jiang B, Liu J, Wang J, Zhao G, Zhao Z. Adaptive Evolution for the Efficient Production of High-Quality d-Lactic Acid Using Engineered Klebsiella pneumoniae. Microorganisms 2024; 12:1167. [PMID: 38930549 PMCID: PMC11205318 DOI: 10.3390/microorganisms12061167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 05/31/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024] Open
Abstract
d-Lactic acid serves as a pivotal platform chemical in the production of poly d-lactic acid (PDLA) and other value-added products. This compound can be synthesized by certain bacteria, including Klebsiella pneumoniae. However, industrial-scale lactic acid production in Klebsiella pneumoniae faces challenges due to growth inhibition caused by lactic acid stress, which acts as a bottleneck in commercial microbial fermentation processes. To address this, we employed a combination of evolutionary and genetic engineering approaches to create an improved Klebsiella pneumoniae strain with enhanced lactic acid tolerance and production. In flask fermentation experiments, the engineered strain achieved an impressive accumulation of 19.56 g/L d-lactic acid, representing the highest production yield observed in Klebsiella pneumoniae to date. Consequently, this strain holds significant promise for applications in industrial bioprocessing. Notably, our genome sequencing and experimental analyses revealed a novel correlation between UTP-glucose-1-phosphate uridylyltransferase GalU and lactic acid resistance in Klebsiella pneumoniae. Further research is warranted to explore the potential of targeting GalU for enhancing d-lactic acid production.
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Affiliation(s)
- Bo Jiang
- State Key Laboratory of Microbial Technology and Institute of Microbial Technology, Shandong University, Qingdao 266237, China; (B.J.); (J.L.); (J.W.)
| | - Jiezheng Liu
- State Key Laboratory of Microbial Technology and Institute of Microbial Technology, Shandong University, Qingdao 266237, China; (B.J.); (J.L.); (J.W.)
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
- Qingdao New Energy Shandong Laboratory, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingnan Wang
- State Key Laboratory of Microbial Technology and Institute of Microbial Technology, Shandong University, Qingdao 266237, China; (B.J.); (J.L.); (J.W.)
| | - Guang Zhao
- State Key Laboratory of Microbial Technology and Institute of Microbial Technology, Shandong University, Qingdao 266237, China; (B.J.); (J.L.); (J.W.)
| | - Zhe Zhao
- State Key Laboratory of Microbial Technology and Institute of Microbial Technology, Shandong University, Qingdao 266237, China; (B.J.); (J.L.); (J.W.)
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Xu B, Zhang W, Zhao E, Hong J, Chen X, Wei Z, Li X. Unveiling malic acid biorefinery: Comprehensive insights into feedstocks, microbial strains, and metabolic pathways. BIORESOURCE TECHNOLOGY 2024; 394:130265. [PMID: 38160850 DOI: 10.1016/j.biortech.2023.130265] [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: 11/15/2023] [Revised: 12/24/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
The over-reliance on fossil fuels and resultant environmental issues necessitate sustainable alternatives. Microbial fermentation of biomass for malic acid production offers a viable, eco-friendly solution, enhancing resource efficiency and minimizing ecological damage. This review covers three core aspects of malic acid biorefining: feedstocks, microbial strains, and metabolic pathways. It emphasizes the significance of utilizing biomass sugars, including the co-fermentation of different sugar types to improve feedstock efficiency. The review discusses microbial strains for malic acid fermentation, addressing challenges related to by-products from biomass breakdown and strategies for overcoming them. It delves into the crucial pathways and enzymes for malic acid production, outlining methods to optimize its metabolism, focusing on enzyme regulation, energy balance, and yield enhancement. These insights contribute to advancing the field of consolidated bioprocessing in malic acid biorefining.
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Affiliation(s)
- Boyang Xu
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China
| | - Wangwei Zhang
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China
| | - Eryong Zhao
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China
| | - Jiong Hong
- School of Life Sciences, University of Science and Technology of China, Hefei City 230026, Anhui Province, PR China
| | - Xiangsong Chen
- Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei City 230031, Anhui Province, PR China
| | - Zhaojun Wei
- School of Biological Sciences and Engineering, North Minzu University, Yinchuan City 750030, Ningxia Hui Autonomous Region, PR China.
| | - Xingjiang Li
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China.
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4
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Chacόn M, Percival E, Bugg TDH, Dixon N. Engineered co-culture for consolidated production of phenylpropanoids directly from aromatic-rich biomass. BIORESOURCE TECHNOLOGY 2024; 391:129935. [PMID: 37923228 DOI: 10.1016/j.biortech.2023.129935] [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: 09/26/2023] [Revised: 10/26/2023] [Accepted: 10/26/2023] [Indexed: 11/07/2023]
Abstract
Consolidated bioprocesses for the in situ hydrolysis and conversion of biomass feedstocks into value-added products offers great potential for both process and cost reduction. However, to date few consolidated bioprocesses have been developed that target aromatic rich feedstock fractions. Reported here is the development of synthetic co-cultivation for the consolidated hydrolysis and valorisation of corncob hydroxycinnamic acids. Biomass hydrolysis was achieved via a secretion module developed in B. subtilis using a genetically encoded biosensor-actuator to secrete hydrolytic enzymes. Conversion was achieved via a biotransformation module developed in E. coli using a suite of plug-and-play encoded enzymes to convert the released hydroxycinnamic acids into high-value phenylpropanoid target compounds. Finally, employing cellulolytic pre-treatment, extractive fermentation and in situ product recovery multiple aromatic products, coniferol and chavicol, were isolated from the same process in high purity.
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Affiliation(s)
- Micaela Chacόn
- Manchester Institute of Biotechnology (MIB), Department of Chemistry, University of Manchester, Manchester M1 7DN, UK
| | - Ellen Percival
- Department of Chemistry, University of Warwick, Coventry CV4 7AK, UK
| | - Timothy D H Bugg
- Department of Chemistry, University of Warwick, Coventry CV4 7AK, UK
| | - Neil Dixon
- Manchester Institute of Biotechnology (MIB), Department of Chemistry, University of Manchester, Manchester M1 7DN, UK.
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Àvila-Cabré S, Pérez-Trujillo M, Albiol J, Ferrer P. Engineering the synthetic β-alanine pathway in Komagataella phaffii for conversion of methanol into 3-hydroxypropionic acid. Microb Cell Fact 2023; 22:237. [PMID: 37978380 PMCID: PMC10655335 DOI: 10.1186/s12934-023-02241-9] [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: 07/31/2023] [Accepted: 11/01/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND Methanol is increasingly gaining attraction as renewable carbon source to produce specialty and commodity chemicals, as it can be generated from renewable sources such as carbon dioxide (CO2). In this context, native methylotrophs such as the yeast Komagataella phaffii (syn Pichia pastoris) are potentially attractive cell factories to produce a wide range of products from this highly reduced substrate. However, studies addressing the potential of this yeast to produce bulk chemicals from methanol are still scarce. 3-Hydroxypropionic acid (3-HP) is a platform chemical which can be converted into acrylic acid and other commodity chemicals and biopolymers. 3-HP can be naturally produced by several bacteria through different metabolic pathways. RESULTS In this study, production of 3-HP via the synthetic β-alanine pathway has been established in K. phaffii for the first time by expressing three heterologous genes, namely panD from Tribolium castaneum, yhxA from Bacillus cereus, and ydfG from Escherichia coli K-12. The expression of these key enzymes allowed a production of 1.0 g l-1 of 3-HP in small-scale cultivations using methanol as substrate. The addition of a second copy of the panD gene and selection of a weak promoter to drive expression of the ydfG gene in the PpCβ21 strain resulted in an additional increase in the final 3-HP titer (1.2 g l-1). The 3-HP-producing strains were further tested in fed-batch cultures. The best strain (PpCβ21) achieved a final 3-HP concentration of 21.4 g l-1 after 39 h of methanol feeding, a product yield of 0.15 g g-1, and a volumetric productivity of 0.48 g l-1 h-1. Further engineering of this strain aiming at increasing NADPH availability led to a 16% increase in the methanol consumption rate and 10% higher specific productivity compared to the reference strain PpCβ21. CONCLUSIONS Our results show the potential of K. phaffii as platform cell factory to produce organic acids such as 3-HP from renewable one-carbon feedstocks, achieving the highest volumetric productivities reported so far for a 3-HP production process through the β-alanine pathway.
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Affiliation(s)
- Sílvia Àvila-Cabré
- Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Míriam Pérez-Trujillo
- Servei de Ressonància Magnètica Nuclear, Facultat de Ciències i Biociències, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Joan Albiol
- Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Pau Ferrer
- Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain.
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Yin FW, Sun XL, Zheng WL, Yin LF, Luo X, Zhang YY, Wang YF, Fu YQ. Development of a Strategy for L-Lactic Acid Production by Rhizopus oryzae Using Zizania latifolia Waste and Cane Molasses as Carbon Sources. Molecules 2023; 28:6234. [PMID: 37687063 PMCID: PMC10488812 DOI: 10.3390/molecules28176234] [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: 08/09/2023] [Revised: 08/21/2023] [Accepted: 08/24/2023] [Indexed: 09/10/2023] Open
Abstract
As a biodegradable and renewable material, polylactic acid is considered a major environmentally friendly alternative to petrochemical plastics. Microbial fermentation is the traditional method for lactic acid production, but it is still too expensive to compete with the petrochemical industry. Agro-industrial wastes are generated from the food and agricultural industries and agricultural practices. The utilization of agro-industrial wastes is an important way to reduce costs, save energy and achieve sustainable development. The present study aimed to develop a method for the valorization of Zizania latifolia waste and cane molasses as carbon sources for L-lactic acid fermentation using Rhizopus oryzae LA-UN-1. The results showed that xylose derived from the acid hydrolysis of Z. latifolia waste was beneficial for cell growth, while glucose from the acid hydrolysis of Z. latifolia waste and mixed sugars (glucose and fructose) from the acid hydrolysis of cane molasses were suitable for the accumulation of lactic acid. Thus, a three-stage carbon source utilization strategy was developed, which markedly improved lactic acid production and productivity, respectively reaching 129.47 g/L and 1.51 g/L·h after 86 h of fermentation. This work demonstrates that inexpensive Z. latifolia waste and cane molasses can be suitable carbon sources for lactic acid production, offering an efficient utilization strategy for agro-industrial wastes.
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Affiliation(s)
- Feng-Wei Yin
- Taizhou Key Laboratory of Biomass Functional Materials Development and Application, Taizhou University, Taizhou 318000, China
| | - Xiao-Long Sun
- Taizhou Key Laboratory of Biomass Functional Materials Development and Application, Taizhou University, Taizhou 318000, China
| | - Wei-Long Zheng
- Taizhou Key Laboratory of Biomass Functional Materials Development and Application, Taizhou University, Taizhou 318000, China
| | - Long-Fei Yin
- Taizhou Key Laboratory of Biomass Functional Materials Development and Application, Taizhou University, Taizhou 318000, China
| | - Xi Luo
- Taizhou Key Laboratory of Biomass Functional Materials Development and Application, Taizhou University, Taizhou 318000, China
| | - Ying-Ying Zhang
- Taizhou Key Laboratory of Biomass Functional Materials Development and Application, Taizhou University, Taizhou 318000, China
| | - Yan-Fei Wang
- Taizhou Institute of Product Quality and Safety Inspection, Taizhou 318000, China
| | - Yong-Qian Fu
- Taizhou Key Laboratory of Biomass Functional Materials Development and Application, Taizhou University, Taizhou 318000, China
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Hu M, Bao W, Peng Q, Hu W, Yang X, Xiang Y, Yan X, Li M, Xu P, He Q, Yang S. Metabolic engineering of Zymomonas mobilis for co-production of D-lactic acid and ethanol using waste feedstocks of molasses and corncob residue hydrolysate. Front Bioeng Biotechnol 2023; 11:1135484. [PMID: 36896016 PMCID: PMC9989019 DOI: 10.3389/fbioe.2023.1135484] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 02/08/2023] [Indexed: 02/25/2023] Open
Abstract
Lactate is the precursor for polylactide. In this study, a lactate producer of Z. mobilis was constructed by replacing ZMO0038 with LmldhA gene driven by a strong promoter PadhB, replacing ZMO1650 with native pdc gene driven by Ptet, and replacing native pdc with another copy of LmldhA driven by PadhB to divert carbon from ethanol to D-lactate. The resultant strain ZML-pdc-ldh produced 13.8 ± 0.2 g/L lactate and 16.9 ± 0.3 g/L ethanol using 48 g/L glucose. Lactate production of ZML-pdc-ldh was further investigated after fermentation optimization in pH-controlled fermenters. ZML-pdc-ldh produced 24.2 ± 0.6 g/L lactate and 12.9 ± 0.8 g/L ethanol as well as 36.2 ± 1.0 g/L lactate and 40.3 ± 0.3 g/L ethanol, resulting in total carbon conversion rate of 98.3% ± 2.5% and 96.2% ± 0.1% with final product productivity of 1.9 ± 0.0 g/L/h and 2.2 ± 0.0 g/L/h in RMG5 and RMG12, respectively. Moreover, ZML-pdc-ldh produced 32.9 ± 0.1 g/L D-lactate and 27.7 ± 0.2 g/L ethanol as well as 42.8 ± 0.0 g/L D-lactate and 53.1 ± 0.7 g/L ethanol with 97.1% ± 0.0% and 99.1% ± 0.8% carbon conversion rate using 20% molasses or corncob residue hydrolysate, respectively. Our study thus demonstrated that it is effective for lactate production by fermentation condition optimization and metabolic engineering to strengthen heterologous ldh expression while reducing the native ethanol production pathway. The capability of recombinant lactate-producer of Z. mobilis for efficient waste feedstock conversion makes it a promising biorefinery platform for carbon-neutral biochemical production.
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Affiliation(s)
- Mimi Hu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
| | - Weiwei Bao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
| | - Qiqun Peng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
| | - Wei Hu
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
| | - Xinyu Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
| | - Yan Xiang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
| | - Xiongying Yan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
| | - Mian Li
- Zhejiang Huakang Pharmaceutical Co., Ltd., Kaihua County, China
| | - Ping Xu
- State Key Laboratory of Microbial Metabolism, and School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Qiaoning He
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
| | - Shihui Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, and School of Life Sciences, Hubei University, Wuhan, China
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Sindhu SS, Sehrawat A, Glick BR. The involvement of organic acids in soil fertility, plant health and environment sustainability. Arch Microbiol 2022; 204:720. [DOI: 10.1007/s00203-022-03321-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/22/2022] [Accepted: 11/03/2022] [Indexed: 11/21/2022]
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Re A, Mazzoli R. Current progress on engineering microbial strains and consortia for production of cellulosic butanol through consolidated bioprocessing. Microb Biotechnol 2022; 16:238-261. [PMID: 36168663 PMCID: PMC9871528 DOI: 10.1111/1751-7915.14148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/01/2022] [Accepted: 09/07/2022] [Indexed: 01/27/2023] Open
Abstract
In the last decades, fermentative production of n-butanol has regained substantial interest mainly owing to its use as drop-in-fuel. The use of lignocellulose as an alternative to traditional acetone-butanol-ethanol fermentation feedstocks (starchy biomass and molasses) can significantly increase the economic competitiveness of biobutanol over production from non-renewable sources (petroleum). However, the low cost of lignocellulose is offset by its high recalcitrance to biodegradation which generally requires chemical-physical pre-treatment and multiple bioreactor-based processes. The development of consolidated processing (i.e., single-pot fermentation) can dramatically reduce lignocellulose fermentation costs and promote its industrial application. Here, strategies for developing microbial strains and consortia that feature both efficient (hemi)cellulose depolymerization and butanol production will be depicted, that is, rational metabolic engineering of native (hemi)cellulolytic or native butanol-producing or other suitable microorganisms; protoplast fusion of (hemi)cellulolytic and butanol-producing strains; and co-culture of (hemi)cellulolytic and butanol-producing microbes. Irrespective of the fermentation feedstock, biobutanol production is inherently limited by the severe toxicity of this solvent that challenges process economic viability. Hence, an overview of strategies for developing butanol hypertolerant strains will be provided.
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Affiliation(s)
- Angela Re
- Centre for Sustainable Future TechnologiesFondazione Istituto Italiano di TecnologiaTorinoItaly,Department of Applied Science and TechnologyPolitecnico di TorinoTurinItaly
| | - Roberto Mazzoli
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems BiologyUniversity of TorinoTorinoItaly
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Fina A, Heux S, Albiol J, Ferrer P. Combining Metabolic Engineering and Multiplexed Screening Methods for 3-Hydroxyprionic Acid Production in Pichia pastoris. Front Bioeng Biotechnol 2022; 10:942304. [PMID: 35935509 PMCID: PMC9354023 DOI: 10.3389/fbioe.2022.942304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 06/22/2022] [Indexed: 11/13/2022] Open
Abstract
Production of 3-hydroxypropionic acid (3-HP) in Pichia pastoris (syn. Komagataella phaffii) via the malonyl-CoA pathway has been recently demonstrated using glycerol as a carbon source, but the reported metrics were not commercially relevant. The flux through the heterologous pathway from malonyl-CoA to 3-HP was hypothesized as the main bottleneck. In the present study, different metabolic engineering approaches have been combined to improve the productivity of the original 3-HP producing strains. To do so, an additional copy of the gene encoding for the potential rate-limiting step of the pathway, i.e., the C-terminal domain of the malonyl-CoA reductase, was introduced. In addition, a variant of the endogenous acetyl-CoA carboxylase (ACC1S1132A) was overexpressed with the aim to increase the delivery of malonyl-CoA. Furthermore, the genes encoding for the pyruvate decarboxylase, aldehyde dehydrogenase and acetyl-CoA synthase, respectively, were overexpressed to enhance conversion of pyruvate into cytosolic acetyl-CoA, and the main gene responsible for the production of the by-product D-arabitol was deleted. Three different screening conditions were used to classify the performance of the different strains: 24-deep-well plates batch cultures, small-scale cultures in falcon tubes using FeedBeads® (i.e., slow release of glycerol over time), and mini bioreactor batch cultures. The best two strains from the FeedBeads® screening, PpHP8 and PpHP18, were tested in bioreactor fed-batch cultures using a pre-fixed exponentially increasing feeding rate. The strain PpHP18 produced up to 37.05 g L−1 of 3-HP at 0.712 g L−1 h−1 with a final product yield on glycerol of 0.194 Cmol−1 in fed-batch cultures. Remarkably, PpHP18 did not rank among the 2-top producer strains in small scale batch cultivations in deep-well plates and mini bioreactors, highlighting the importance of multiplexed screening conditions for adequate assessment of metabolic engineering strategies. These results represent a 50% increase in the product yield and final concentration, as well as over 30% increase in volumetric productivity compared to the previously obtained metrics for P. pastoris. Overall, the combination of glycerol as carbon source and a metabolically engineered P. pastoris strain resulted in the highest 3-HP concentration and productivity reported so far in yeast.
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Affiliation(s)
- Albert Fina
- Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Stephanie Heux
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | - Joan Albiol
- Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Pau Ferrer
- Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- *Correspondence: Pau Ferrer,
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11
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Kim SR, Eckert CA, Mazzoli R. Editorial: Microorganisms for Consolidated 2nd Generation Biorefining. Front Microbiol 2022; 13:940610. [PMID: 35783433 PMCID: PMC9248810 DOI: 10.3389/fmicb.2022.940610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 05/23/2022] [Indexed: 12/01/2022] Open
Affiliation(s)
- Soo Rin Kim
- School of Food Science and Biotechnology, Research Institute of Tailored Food Technology, Kyungpook National University, Daegu, South Korea
| | - Carrie A. Eckert
- Synthetic Biology Group, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Roberto Mazzoli
- Structural and Functional Biochemistry, Laboratory of Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
- *Correspondence: Roberto Mazzoli
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12
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Son J, Joo JC, Baritugo KA, Jeong S, Lee JY, Lim HJ, Lim SH, Yoo JI, Park SJ. Consolidated microbial production of four-, five-, and six-carbon organic acids from crop residues: Current status and perspectives. BIORESOURCE TECHNOLOGY 2022; 351:127001. [PMID: 35292386 DOI: 10.1016/j.biortech.2022.127001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/08/2022] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
The production of platform organic acids has been heavily dependent on petroleum-based industries. However, petrochemical-based industries that cannot guarantee a virtuous cycle of carbons released during various processes are now facing obsolescence because of the depletion of finite fossil fuel reserves and associated environmental pollutions. Thus, the transition into a circular economy in terms of the carbon footprint has been evaluated with the development of efficient microbial cell factories using renewable feedstocks. Herein, the recent progress on bio-based production of organic acids with four-, five-, and six-carbon backbones, including butyric acid and 3-hydroxybutyric acid (C4), 5-aminolevulinic acid and citramalic acid (C5), and hexanoic acid (C6), is discussed. Then, the current research on the production of C4-C6 organic acids is illustrated to suggest future directions for developing crop-residue based consolidated bioprocessing of C4-C6 organic acids using host strains with tailor-made capabilities.
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Affiliation(s)
- Jina Son
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Jeong Chan Joo
- Department of Biotechnology, The Catholic University of Korea, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Kei-Anne Baritugo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Seona Jeong
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Ji Yeon Lee
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Hye Jin Lim
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Seo Hyun Lim
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Jee In Yoo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Si Jae Park
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea.
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