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Jo SY, Lim SH, Lee JY, Son J, Choi JI, Park SJ. Microbial production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), from lab to the shelf: A review. Int J Biol Macromol 2024; 274:133157. [PMID: 38901504 DOI: 10.1016/j.ijbiomac.2024.133157] [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: 02/09/2024] [Revised: 06/11/2024] [Accepted: 06/12/2024] [Indexed: 06/22/2024]
Abstract
Polyhydroxyalkanoates (PHAs) are natural biopolyesters produced by microorganisms that represent one of the most promising candidates for the replacement of conventional plastics due to their complete biodegradability and advantageous material properties which can be modulated by varying their monomer composition. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] has received particular research attention because it can be synthesized based on the same microbial platform developed for poly(3-hydroxybutyrate) [P(3HB)] without much modification, with as high productivity as P(3HB). It also offers more useful mechanical and thermal properties than P(3HB), which broaden its application as a biocompatible and biodegradable polyester. However, a significant commercial disadvantage of P(3HB-co-3HV) is its rather high production cost, thus many studies have investigated the economical synthesis of P(3HB-co-3HV) from structurally related and unrelated carbon sources in both wild-type and recombinant microbial strains. A large number of metabolic engineering strategies have also been proposed to tune the monomer composition of P(3HB-co-3HV) and thus its material properties. In this review, recent metabolic engineering strategies designed for enhanced production of P(3HB-co-3HV) are discussed, along with their current status, limitations, and future perspectives.
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Affiliation(s)
- Seo Young Jo
- 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
| | - 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
| | - 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
| | - Jong-Il Choi
- Department of Biotechnology and Bioengineering, Chonnam National University, Gwangju 61186, 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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2
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Amabile C, Abate T, Muñoz R, Chianese S, Musmarra D. Production of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from methane and volatile fatty acids: properties, metabolic routes and current trend. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172138. [PMID: 38582106 DOI: 10.1016/j.scitotenv.2024.172138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/21/2024] [Accepted: 03/30/2024] [Indexed: 04/08/2024]
Abstract
Polyhydroxyalkanoates (PHAs) are biobased and biodegradable polymers that could effectively replace fossil-based and non-biodegradable plastics. However, their production is currently limited by the high production costs, mainly due to the costly carbon sources used, low productivity and quality of the materials produced. A potential solution lies in utilizing cheap and renewable carbon sources as the primary feedstock during the biological production of PHAs, paving the way for a completely sustainable and economically viable process. In this review, the opportunities and challenges related to the production of polyhydroxyalkanoates using methane and volatile fatty acids (VFAs) as substrates were explored, with a focus on poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate). The discussion reports the current knowledge about promising Type II methanotrophs, the impact of process parameters such as limiting nutrients, CH4:O2 ratio and temperature, the type of co-substrate and its concentration. Additionally, the strategies developed until now to enhance PHA production yields were also discussed.
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Affiliation(s)
- Claudia Amabile
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy; Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain
| | - Teresa Abate
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy; Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain
| | - Raul Muñoz
- Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain
| | - Simeone Chianese
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy.
| | - Dino Musmarra
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy
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3
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Fukala I, Kučera I. Natural Polyhydroxyalkanoates-An Overview of Bacterial Production Methods. Molecules 2024; 29:2293. [PMID: 38792154 PMCID: PMC11124392 DOI: 10.3390/molecules29102293] [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: 04/05/2024] [Revised: 05/05/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Polyhydroxyalkanoates (PHAs) are intracellular biopolymers that microorganisms use for energy and carbon storage. They are mechanically similar to petrochemical plastics when chemically extracted, but are completely biodegradable. While they have potential as a replacement for petrochemical plastics, their high production cost using traditional carbon sources remains a significant challenge. One potential solution is to modify heterotrophic PHA-producing strains to utilize alternative carbon sources. An alternative approach is to utilize methylotrophic or autotrophic strains. This article provides an overview of bacterial strains employed for PHA production, with a particular focus on those exhibiting the highest PHA content in dry cell mass. The strains are organized according to their carbon source utilization, encompassing autotrophy (utilizing CO2, CO) and methylotrophy (utilizing reduced single-carbon substrates) to heterotrophy (utilizing more traditional and alternative substrates).
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Affiliation(s)
| | - Igor Kučera
- Department of Biochemistry, Faculty of Science, Masaryk University, Kotlářská 267/2, CZ-61137 Brno, Czech Republic;
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4
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Hozumi Y, Hachisuka SI, Tomita H, Kikukawa H, Matsumoto K. Engineering of the Long-Main-Chain Monomer-Incorporating Polyhydroxyalkanoate Synthase PhaC AR for the Biosynthesis of Poly[( R)-3-hydroxybutyrate- co-6-hydroxyhexanoate]. Biomacromolecules 2024; 25:2973-2979. [PMID: 38588330 DOI: 10.1021/acs.biomac.4c00116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Polyhydroxyalkanoate (PHA) synthases (PhaCs) are useful and versatile tools for the production of aliphatic polyesters. Here, the chimeric PHA synthase PhaCAR was engineered to increase its capacity to incorporate unusual 6-hydroxyhexanoate (6HHx) units. Mutations at positions 149 and 314 in PhaCAR were previously found to increase the incorporation of an analogous natural monomer, 3-hydroxyhexanoate (3HHx). We attempted to repurpose the mutations to produce 6HHx-containing polymers. Site-directed saturation mutants at these positions were applied for P(3HB-co-6HHx) synthesis in Escherichia coli. As a result, the N149D and F314Y mutants effectively increased the 6HHx fraction. Moreover, the pairwise NDFY mutation further increased the 6HHx fraction, which reached 22 mol %. This increase was presumably caused by altered enzyme activity rather than altered expression levels, as assessed based on immunoblot analysis. The glass transition temperature and crystallinity of P(3HB-co-6HHx) decreased as the 6HHx fraction increased.
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Affiliation(s)
- Yuka Hozumi
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, N13W8, Kitaku, Sapporo 060-8628, Japan
| | - Shin-Ichi Hachisuka
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo 060-8628, Japan
| | - Hiroya Tomita
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo 060-8628, Japan
| | - Hiroshi Kikukawa
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo 060-8628, Japan
| | - Ken'ichiro Matsumoto
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo 060-8628, Japan
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5
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Amabile C, Abate T, Marcos E, Chianese S, Musmarra D, Muñoz R. Exploring New Strategies for Optimizing the Production of Poly(3-hydroxybutyrate- co-3-hydroxyvalerate) from Methane and VFAs in Synthetic Cocultures and Mixed Methanotrophic Consortia. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2024; 12:4690-4699. [PMID: 38516398 PMCID: PMC10954047 DOI: 10.1021/acssuschemeng.3c08570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/19/2024] [Accepted: 02/21/2024] [Indexed: 03/23/2024]
Abstract
In this work, the potential of a synthetic coculture and a mixed methanotrophic consortium to synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from renewable and waste-based feedstocks was assessed batchwise. Methylocystis parvuscocultivated with Rhodococcus opacus and a Methylocystis-enriched culture previously grown on methane were subjected to nutrient starvation in a medium enriched with valeric acid (30% w w-1 of Ctot) or with a VFAs mixture containing acetic, propionic, butyric, and valeric acids (15% w w-1 of Ctot) under a CH4:O2 or air atmosphere. For all test series, pH was adjusted to 7 after adding the cosubstrates, and a negligible substrate consumption or polymer production was considered the end point of the trial. Results showed that valeric acid promoted PHBV accumulation in both cultures regardless of the atmosphere. Interestingly, the mixture of VFAs supported PHBV accumulation only in the presence of methane. The highest PHBV contents for the coculture and the mixed consortium, equal to 73.7 ± 2.5% w w-1 and 49.6 ± 13% w w-1, respectively, were obtained with methane and the VFAs mixture. This study demonstrates the suitability of cocultures and biobased cosubstrates for the sustainable production of the biodegradable polymer PHBV.
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Affiliation(s)
- Claudia Amabile
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, Aversa 81031, Italy
- Institute
of Sustainable Processes, University of
Valladolid, Dr. Mergelina,
s/n, Valladolid 47011, Spain
| | - Teresa Abate
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, Aversa 81031, Italy
- Institute
of Sustainable Processes, University of
Valladolid, Dr. Mergelina,
s/n, Valladolid 47011, Spain
| | - Enrique Marcos
- Institute
of Sustainable Processes, University of
Valladolid, Dr. Mergelina,
s/n, Valladolid 47011, Spain
| | - Simeone Chianese
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, Aversa 81031, Italy
| | - Dino Musmarra
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, Aversa 81031, Italy
| | - Raul Muñoz
- Institute
of Sustainable Processes, University of
Valladolid, Dr. Mergelina,
s/n, Valladolid 47011, Spain
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6
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Gęsicka A, Gutowska N, Palaniappan S, Oleskowicz-Popiel P, Łężyk M. Enrichment of mixed methanotrophic cultures producing polyhydroxyalkanoates (PHAs) from various environmental sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168844. [PMID: 38029989 DOI: 10.1016/j.scitotenv.2023.168844] [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: 07/13/2023] [Revised: 10/31/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023]
Abstract
Methanotrophic bacteria can use atmospheric methane (CH4) as a sole carbon source for the growth and production of polyhydroxyalkanoates (PHA). The development of CH4 bioconversion processes relies heavily on the selection of an efficient methanotrophic culture. This research assessed the effect of selected growth conditions, such as nitrogen sources on the enrichment of methanotrophic cultures from various environments for PHA accumulation. Nitrate-based medium favoured the culture growth and selection for PHA-producing methanotrophic cultures with Methylocystis sp. as a major genus and accumulation of up to 27 % polyhydroxybutyrate (PHB) in the biomass. Three PHB-producing cultures: enriched from waste activated sludge (AS), peat bog soil (PB) and landfill biocover soil (LB) were then tested for their ability to produce PHA copolymer at different CH4:O2 ratios. All enriched cultures were able to utilise valeric acid as a cosubstrate for the accumulation of PHA with a 3-hydroxyvaleric (3HV) fraction of 21-41 mol% depending on the inoculum source and CH4 concentration. The process performance of selected cultures was evaluated and compared to the culture of reference strain Methylocystis hirsuta DSM 18500. All mixed cultures irrespective of their inoculum source had similar levels of 3HV fraction in the PHA (38 ± 2 mol%). The highest poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) production was observed for AS culture at 10 % CH4 with an accumulation of 27 ± 3 % of dry cell weight (DCW), 3HV fraction of 39 ± 2 mol% and yield of 0.42 ± 0.02 g-PHA/g-substrate.
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Affiliation(s)
- Aleksandra Gęsicka
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Natalia Gutowska
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Sivasankar Palaniappan
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Piotr Oleskowicz-Popiel
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Mateusz Łężyk
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland.
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7
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Tran MH, Choi TR, Yang YH, Lee OK, Lee EY. An efficient and eco-friendly approach for the sustainable recovery and properties characterization of polyhydroxyalkanoates produced by methanotrophs. Int J Biol Macromol 2024; 257:128687. [PMID: 38101655 DOI: 10.1016/j.ijbiomac.2023.128687] [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: 09/05/2023] [Revised: 11/29/2023] [Accepted: 12/06/2023] [Indexed: 12/17/2023]
Abstract
Synthetic biodegradable and bio-based polymers have emerged as sustainable alternatives to nonrenewable petroleum-derived polymers which cause serious environmental issues. In particular, polyhydroxyalkanoates (PHA) are promising biopolymers owing to their outstanding biodegradability and biocompatibility. The production of the homopolymer poly(3-hydroxybutyrate) (PHB) and copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from type II methanotrophs via microbial fermentation was presented. For the efficient extraction and recovery of intracellular PHA from methanotrophs, different extraction approaches were investigated including solvent extraction using 1,3-dioxolane as a green solvent, integrated cell lysis and solvent extraction, and cell digestion without the use of organic solvents. Among various extraction approaches, the integrated method exhibited the highest extraction performance, with PHA recovery and purity exceeding 91 % and 93 %, respectively, even when the PHA content of the cells was low. Furthermore, the molecular weight, thermal stability, and mechanical properties of the recovered PHA were comprehensively analyzed to suggest its suitable practical applications. The obtained properties were comparable to that of the commercial PHA products and PHA produced from other microbial species, indicating an efficient recovery of high-quality PHA produced from methanotrophs.
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Affiliation(s)
- My Ha Tran
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Tae-Rim Choi
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | - Ok Kyung Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
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8
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Ma R, Li J, Tyagi RD, Zhang X. Carbon dioxide and methane as carbon source for the production of polyhydroxyalkanoates and concomitant carbon fixation. BIORESOURCE TECHNOLOGY 2024; 391:129977. [PMID: 37925086 DOI: 10.1016/j.biortech.2023.129977] [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: 10/11/2023] [Revised: 11/01/2023] [Accepted: 11/01/2023] [Indexed: 11/06/2023]
Abstract
The currently used plastics are non-biodegradable, and cause greenhouse gases (GHGs) emission as they are petroleum-based. Polyhydroxyalkanoates (PHAs) are biopolymers with excellent biodegradability and biocompatibility, which can be used to replace petroleum-based plastics. A variety of microorganisms have been found to synthesize PHAs by using typical GHGs: carbon dioxide and methane as carbon sources. Converting carbon dioxide (CO2) and methane (CH4) to PHAs is an attractive option for carbon capture and biodegradable plastic production. In this review, the microorganisms capable of using CO2 and CH4 to produce PHAs were summarized. The metabolic mechanism, PHAs production process, and the factors influencing the production process are illustrated. The currently used optimization techniques to improve the yield of PHAs are discussed. The challenges and future prospects for developing economically viable PHAs production using GHGs as carbon source are identified. This work provides an insight for achieving carbon sequestration and bioplastics based circular economy.
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Affiliation(s)
- Rui Ma
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen Guangdong 518055, PR China
| | - Ji Li
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen Guangdong 518055, PR China
| | - R D Tyagi
- Chief Scientific Officer, BOSK-Bioproducts, Quebec, Canada
| | - Xiaolei Zhang
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen Guangdong 518055, PR China.
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9
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Yang F, Wang H, Zhao C, Zhang L, Liu X, Park H, Yuan Y, Ye JW, Wu Q, Chen GQ. Metabolic engineering of Halomonas bluephagenesis for production of five carbon molecular chemicals derived from L-lysine. Metab Eng 2024; 81:227-237. [PMID: 38072357 DOI: 10.1016/j.ymben.2023.12.001] [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: 09/20/2023] [Revised: 10/28/2023] [Accepted: 12/01/2023] [Indexed: 12/31/2023]
Abstract
5-Aminovaleric acid (5-AVA), 5-hydroxyvalerate (5HV), copolymer P(3HB-co-5HV) of 3-hydroxybutyrate (3HB) and 5HV were produced from L-lysine as a substrate by recombinant Halomonas bluephagenesis constructed based on codon optimization, deletions of competitive pathway and L-lysine export protein, and three copies of davBA genes encoding L-lysine monooxygenase (DavB) and 5-aminovaleramide amidohydrolase (DavA) inserted into its genome to form H. bluephagenesis YF117ΔgabT1+2, which produced 16.4 g L-1 and 67.4 g L-1 5-AVA in flask cultures and in 7 L bioreactor, respectively. It was able to de novo synthesize 5-AVA from glucose by L-lysine-overproducing H. bluephagenesis TD226. Corn steep liquor was used instead of yeast extract for cost reduction during the 5-AVA production. Using promoter engineering based on Pporin mutant library for downstream genes, H. bluephagenesis YF117 harboring pSEVA341-Pporin42-yqhDEC produced 6 g L-1 5HV in shake flask growth, while H. bluephagenesis YF117 harboring pSEVA341-Pporin42-yqhDEC-Pporin278-phaCRE-abfT synthesized 42 wt% P(3HB-co-4.8 mol% 5HV) under the same condition. Thus, H. bluephagenesis was successfully engineered to produce 5-AVA and 5HV in supernatant and intracellular P(3HB-co-5HV) utilizing L-lysine as the substrate.
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Affiliation(s)
- Fang Yang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Huan Wang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Cuihuan Zhao
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Lizhan Zhang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xu Liu
- PhaBuilder Biotech Co. Ltd., Shunyi District, Zhaoquan Ying, Beijing, 101309, China
| | - Helen Park
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yiping Yuan
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jian-Wen Ye
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Qiong Wu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Guo-Qiang Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, China; Center for Synthetic and Systems Biology, Tsinghua University, Beijing, 100084, China; Tsinghua-Peking Center for Life Sciences, Beijing, China; MOE Key Lab of Industrial Biocatalysis, Dept Chemical Engineering, Tsinghua University, Beijing, 100084, China.
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10
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Lee OK, Kang SG, Choi TR, Yang YH, Lee EY. Production and characterization of a biodegradable polymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), using the type II methanotroph, Methylocystis sp. MJC1. BIORESOURCE TECHNOLOGY 2023; 389:129853. [PMID: 37813313 DOI: 10.1016/j.biortech.2023.129853] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/06/2023] [Accepted: 10/06/2023] [Indexed: 10/11/2023]
Abstract
The production of polyhydroxyalkanoates (PHAs) through the biological conversion of methane is a promising solution to address both methane emissions and plastic waste. Type II methanotrophs naturally accumulate a representative PHA, poly(3-hydroxybutyrate) (PHB), using methane as the sole carbon source. In this study, we aimed to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV copolymer) with improved properties compared with PHB, using the type II methanotroph, Methylocystis sp. MJC1. We optimized the pH, valerate concentration, and valerate supply time in a one-step cultivation process using a gas bioreactor to enhance PHBV copolymer production yield and the 3-hydroxyvalerate (3HV) molar fraction. Under the optimal conditions, the biomass reached 21.3 g DCW/L, and PHBV copolymer accumulation accounted for 41.9 % of the dried cell weight, with a 3HV molar fraction of 28.4 %. The physicochemical properties of the purified PHBV copolymer were characterized using NMR, FTIR, TGA, DSC, and GPC.
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Affiliation(s)
- Ok Kyung Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Seung Gi Kang
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Tae-Rim Choi
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
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11
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Averesch NJH, Berliner AJ, Nangle SN, Zezulka S, Vengerova GL, Ho D, Casale CA, Lehner BAE, Snyder JE, Clark KB, Dartnell LR, Criddle CS, Arkin AP. Microbial biomanufacturing for space-exploration-what to take and when to make. Nat Commun 2023; 14:2311. [PMID: 37085475 PMCID: PMC10121718 DOI: 10.1038/s41467-023-37910-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 04/05/2023] [Indexed: 04/23/2023] Open
Abstract
As renewed interest in human space-exploration intensifies, a coherent and modernized strategy for mission design and planning has become increasingly crucial. Biotechnology has emerged as a promising approach to increase resilience, flexibility, and efficiency of missions, by virtue of its ability to effectively utilize in situ resources and reclaim resources from waste streams. Here we outline four primary mission-classes on Moon and Mars that drive a staged and accretive biomanufacturing strategy. Each class requires a unique approach to integrate biomanufacturing into the existing mission-architecture and so faces unique challenges in technology development. These challenges stem directly from the resources available in a given mission-class-the degree to which feedstocks are derived from cargo and in situ resources-and the degree to which loop-closure is necessary. As mission duration and distance from Earth increase, the benefits of specialized, sustainable biomanufacturing processes also increase. Consequentially, we define specific design-scenarios and quantify the usefulness of in-space biomanufacturing, to guide techno-economics of space-missions. Especially materials emerged as a potentially pivotal target for biomanufacturing with large impact on up-mass cost. Subsequently, we outline the processes needed for development, testing, and deployment of requisite technologies. As space-related technology development often does, these advancements are likely to have profound implications for the creation of a resilient circular bioeconomy on Earth.
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Affiliation(s)
- Nils J H Averesch
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA.
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA.
| | - Aaron J Berliner
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA.
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA.
| | - Shannon N Nangle
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, USA.
- Circe Bioscience Inc., Somerville, MA, USA.
| | - Spencer Zezulka
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA
- School of Information, University of California Berkeley, Berkeley, CA, USA
| | - Gretchen L Vengerova
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA
| | - Davian Ho
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA
| | - Cameran A Casale
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA
| | - Benjamin A E Lehner
- Department of Bionanoscience, Delft University of Technology, Delft, South Holland, Netherlands
| | | | - Kevin B Clark
- Cures Within Reach, Chicago, IL, USA
- Champions Program, eXtreme Science and Engineering Discovery Environment (XSEDE), Urbana, IL, USA
| | - Lewis R Dartnell
- Department of Life Sciences, University of Westminster, London, UK
| | - Craig S Criddle
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA
| | - Adam P Arkin
- Center for the Utilization of Biological Engineering in Space (CUBES), Berkeley, CA, USA
- Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA
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12
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Mrudulakumari Vasudevan U, Mai DHA, Krishna S, Lee EY. Methanotrophs as a reservoir for bioactive secondary metabolites: Pitfalls, insights and promises. Biotechnol Adv 2023; 63:108097. [PMID: 36634856 DOI: 10.1016/j.biotechadv.2023.108097] [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: 10/03/2022] [Revised: 12/10/2022] [Accepted: 01/06/2023] [Indexed: 01/11/2023]
Abstract
Methanotrophs are potent natural producers of several bioactive secondary metabolites (SMs) including isoprenoids, polymers, peptides, and vitamins. Cryptic biosynthetic gene clusters identified from these microbes via genome mining hinted at the vast and hidden SM biosynthetic potential of these microbes. Central carbon metabolism in methanotrophs offers rare pathway intermediate pools that could be further diversified using advanced synthetic biology tools to produce valuable SMs; for example, plant polyketides, rare carotenoids, and fatty acid-derived SMs. Recent advances in pathway reconstruction and production of isoprenoids, squalene, ectoine, polyhydroxyalkanoate copolymer, cadaverine, indigo, and shinorine serve as proof-of-concept. This review provides theoretical guidance for developing methanotrophs as microbial chassis for high-value SMs. We summarize the distinct secondary metabolic potentials of type I and type II methanotrophs, with specific attention to products relevant to biomedical applications. This review also includes native and non-native SMs from methanotrophs, their therapeutic potential, strategies to induce silent biosynthetic gene clusters, and challenges.
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Affiliation(s)
- Ushasree Mrudulakumari Vasudevan
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Dung Hoang Anh Mai
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Shyam Krishna
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
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13
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Rehakova V, Pernicova I, Kourilova X, Sedlacek P, Musilova J, Sedlar K, Koller M, Kalina M, Obruca S. Biosynthesis of versatile PHA copolymers by thermophilic members of the genus Aneurinibacillus. Int J Biol Macromol 2023; 225:1588-1598. [PMID: 36435467 DOI: 10.1016/j.ijbiomac.2022.11.215] [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: 07/27/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022]
Abstract
Thermophilic members of the genus Aneurinibacillus constitute a remarkable group of microorganisms that exhibit extraordinary flexibility in terms of polyhydroxyalkanoates (PHA) synthesis. In this study, we demonstrate that these Gram-positive bacteria are capable of the utilization of selected lactones, namely, γ-valerolactone (GVL), γ-hexalactone (GHL), and δ-valerolactone (DVL) as the structural precursors of related PHA monomers. In the presence of GVL, a PHA copolymer consisting of 3-hydroxybutyrate, 3-hydroxyvalerate, and also 4-hydroxyvalerate was synthesized, with a 4 HV fraction as high as 53.1 mol%. Similarly, the application of GHL resulted in the synthesis of PHA copolymer containing 4-hydroxyhexanaote (4HHx) (4HHx fraction reached up to 11.5 mol%) and DVL was incorporated into PHA in form of 5-hydroxyvalerate (5 HV) (maximal 5 HV content was 44.2 mol%). The produced materials were characterized by thermoanalytical and spectroscopic methods; the results confirmed extremely appealing material properties of produced copolymers. Further, due to their unique metabolic features and capability of incorporating various PHA monomers into the PHA chain, thermophilic Aneurinibacillus spp. can be considered not only promising chassis for PHA production but also potential donors of PHA-relevant genes to improve PHA production in other thermophiles by using approaches of synthetic biology.
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Affiliation(s)
- Veronika Rehakova
- Department of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology, Brno, Czech Republic
| | - Iva Pernicova
- Department of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology, Brno, Czech Republic
| | - Xenie Kourilova
- Department of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology, Brno, Czech Republic
| | - Petr Sedlacek
- Department of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Brno, Czech Republic
| | - Jana Musilova
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
| | - Karel Sedlar
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
| | - Martin Koller
- Research Management and Service, c/o Institute of Chemistry, NAWI Graz, University of Graz, Graz, Austria; ARENA Arbeitsgemeinschaft für Ressourcenschonende & Nachhaltige Technologien, Graz, Austria
| | - Michal Kalina
- Department of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Brno, Czech Republic
| | - Stanislav Obruca
- Department of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology, Brno, Czech Republic.
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14
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Ray S, Jin JO, Choi I, Kim M. Recent trends of biotechnological production of polyhydroxyalkanoates from C1 carbon sources. Front Bioeng Biotechnol 2023; 10:907500. [PMID: 36686222 PMCID: PMC9852868 DOI: 10.3389/fbioe.2022.907500] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 12/06/2022] [Indexed: 01/09/2023] Open
Abstract
Growing concerns over the use of limited fossil fuels and their negative impacts on the ecological niches have facilitated the exploration of alternative routes. The use of conventional plastic material also negatively impacts the environment. One such green alternative is polyhydroxyalkanoates, which are biodegradable, biocompatible, and environmentally friendly. Recently, researchers have focused on the utilization of waste gases particularly those belonging to C1 sources derived directly from industries and anthropogenic activities, such as carbon dioxide, methane, and methanol as the substrate for polyhydroxyalkanoates production. Consequently, several microorganisms have been exploited to utilize waste gases for their growth and biopolymer accumulation. Methylotrophs such as Methylobacterium organophilum produced highest amount of PHA up to 88% using CH4 as the sole carbon source and 52-56% with CH3OH. On the other hand Cupriavidus necator, produced 71-81% of PHA by utilizing CO and CO2 as a substrate. The present review shows the potential of waste gas valorization as a promising solution for the sustainable production of polyhydroxyalkanoates. Key bottlenecks towards the usage of gaseous substrates obstructing their realization on a large scale and the possible technological solutions were also highlighted. Several strategies for PHA production using C1 gases through fermentation and metabolic engineering approaches are discussed. Microbes such as autotrophs, acetogens, and methanotrophs can produce PHA from CO2, CO, and CH4. Therefore, this article presents a vision of C1 gas into bioplastics are prospective strategies with promising potential application, and aspects related to the sustainability of the system.
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Affiliation(s)
- Subhasree Ray
- Research Institute of Cell Culture, Yeungnam University, Gyeongsan, South Korea,Department of Life Science, School of Basic Science and Research, Sharda University, Greater Noida, India,*Correspondence: Myunghee Kim, ; Subhasree Ray,
| | - Jun-O Jin
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea,Department of Food Science and Technology, Yeungnam University, Gyeongsan, South Korea
| | - Inho Choi
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea,Department of Food Science and Technology, Yeungnam University, Gyeongsan, South Korea
| | - Myunghee Kim
- Research Institute of Cell Culture, Yeungnam University, Gyeongsan, South Korea,Department of Food Science and Technology, Yeungnam University, Gyeongsan, South Korea,*Correspondence: Myunghee Kim, ; Subhasree Ray,
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15
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Naizabekov S, Hyun SW, Na JG, Yoon S, Lee OK, Lee EY. Comparative genomic analysis of Methylocystis sp. MJC1 as a platform strain for polyhydroxybutyrate biosynthesis. PLoS One 2023; 18:e0284846. [PMID: 37163531 PMCID: PMC10171618 DOI: 10.1371/journal.pone.0284846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 04/06/2023] [Indexed: 05/12/2023] Open
Abstract
Biodegradable polyhydroxybutyrate (PHB) can be produced from methane by some type II methanotroph such as the genus Methylocystis. This study presents the comparative genomic analysis of a newly isolated methanotroph, Methylocystis sp. MJC1 as a biodegradable PHB-producing platform strain. Methylocystis sp. MJC1 accumulates up to 44.5% of PHB based on dry cell weight under nitrogen-limiting conditions. To facilitate its development as a PHB-producing platform strain, the complete genome sequence of Methylocystis sp. MJC1 was assembled, functionally annotated, and compared with genomes of other Methylocystis species. Phylogenetic analysis has shown that Methylocystis parvus to be the closest species to Methylocystis sp. MJC1. Genome functional annotation revealed that Methylocystis sp. MJC1 contains all major type II methanotroph biochemical pathways such as the serine cycle, EMC pathway, and Krebs cycle. Interestingly, Methylocystis sp. MJC1 has both particulate and soluble methane monooxygenases, which are not commonly found among Methylocystis species. In addition, this species also possesses most of the RuMP pathway reactions, a characteristic of type I methanotrophs, and all PHB biosynthetic genes. These comparative analysis would open the possibility of future practical applications such as the development of organism-specific genome-scale models and application of metabolic engineering strategies to Methylocystis sp. MJC1.
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Affiliation(s)
- Sanzhar Naizabekov
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Seung Woon Hyun
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Jeong-Geol Na
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, Republic of Korea
| | - Sukhwan Yoon
- Department of Civil & Environmental Engineering, Korea Advanced Institute of Science & Technology, Daejeon, Republic of Korea
| | - Ok Kyung Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do, Republic of Korea
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16
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Rodríguez Y, García S, Pérez R, Lebrero R, Muñoz R. Optimization of nitrogen feeding strategies for improving polyhydroxybutyrate production from biogas by Methylocystis parvus str. OBBP in a stirred tank reactor. CHEMOSPHERE 2022; 299:134443. [PMID: 35364084 DOI: 10.1016/j.chemosphere.2022.134443] [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: 06/07/2021] [Revised: 03/07/2022] [Accepted: 03/24/2022] [Indexed: 06/14/2023]
Abstract
The design of efficient cultivation strategies to produce bioplastics from biogas is crucial for the implementation of this biorefinery process. In this work, biogas-based polyhydroxybutyrate (PHB) production and CH4 biodegradation performance was investigated for the first time in a stirred tank bioreactor inoculated with Methylocystis parvus str. OBBP. Decreasing nitrogen loading rates in continuous mode and alternating feast:famine regimes of 24 h-cycles, and alternating feast:famine regimes of 24 h:24 h and 24 h:48 h were tested. Continuous N feeding did not support an effective PHB production despite the occurrence of nitrogen limiting conditions. Feast-famine cycles of 24 h:24 h (with 50% stoichiometric nitrogen supply) supported the maximum PHB production (20 g-PHB m-3 d-1) without compromising the CH4-elimination capacity (25 g m-3 h-1) of the system. Feast:famine ratios ≤1:2 entailed the deterioration of process performance at stoichiometric nitrogen inputs ≤60%.
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Affiliation(s)
- Yadira Rodríguez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Silvia García
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Rebeca Pérez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Raquel Lebrero
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Raúl Muñoz
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
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17
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Satoh K, Kawakami T, Isobe N, Pasquier L, Tomita H, Zinn M, Matsumoto K. Versatile aliphatic polyester biosynthesis system for producing random and block copolymers composed of 2-, 3-, 4-, 5-, and 6-hydroxyalkanoates using the sequence-regulating polyhydroxyalkanoate synthase PhaC AR. Microb Cell Fact 2022; 21:84. [PMID: 35568875 PMCID: PMC9107728 DOI: 10.1186/s12934-022-01811-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 05/01/2022] [Indexed: 11/13/2022] Open
Abstract
Background Polyhydroxyalkanoates (PHAs) are microbial polyesters synthesized by PHA synthases. Naturally occurring PHA copolymers possess a random monomer sequence. The development of PhaCAR, a unique sequence-regulating PHA synthase, has enabled the spontaneous biosynthesis of PHA block copolymers. PhaCAR synthesizes both a block copolymer poly(2-hydroxybutyrate)-b-poly(3-hydroxybutyrate) [P(2HB)-b-P(3HB)], and a random copolymer, poly(3HB-co-3-hydroxyhexanoate), indicating that the combination of monomers determines the monomer sequence. Therefore, in this study, we explored the substrate scope of PhaCAR and the monomer sequences of the resulting copolymers to identify the determinants of the monomer sequence. PhaCAR is a class I PHA synthase that is thought to incorporate long-main-chain hydroxyalkanoates (LMC HAs, > C3 in the main [backbone] chain). Thus, the LMC monomers, 4-hydroxy-2-methylbutyrate (4H2MB), 5-hydroxyvalerate (5HV), and 6-hydroxyhexanoate (6HHx), as well as 2HB, 3HB, and 3-hydroxypropionate (3HP) were tested. Results Recombinant Escherichia coli harboring PhaCAR, CoA transferase and CoA ligase genes was used for PHA production. The medium contained the monomer precursors, 2HB, 3HB, 3HP, 4H2MB, 5HV, and 6HHx, either individually or in combination. As a result, homopolymers were obtained only for 3HB and 3HP. Moreover, 3HB and 3HP were randomly copolymerized by PhaCAR. 3HB-based binary copolymers P(3HB-co-LMC HA)s containing up to 2.9 mol% 4H2MB, 4.8 mol% 5HV, or 1.8 mol% 6HHx were produced. Differential scanning calorimetry analysis of the copolymers indicated that P(3HB-co-LMC HA)s had a random sequence. In contrast, combining 3HP and 2HB induced the synthesis of P(3HP)-b-P(2HB). Similarly, P(2HB) segment-containing block copolymers P(3HB-co-LMC HA)-b-P(2HB)s were synthesized. Binary copolymers of LMC HAs and 2HB were not obtained, indicating that the 3HB or 3HP unit is essential to the polymer synthesis. Conclusion PhaCAR possesses a wide substrate scope towards 2-, 3-, 4-, 5-, and 6-hydroxyalkanoates. 3HB or 3HP units are essential for polymer synthesis using PhaCAR. The presence of a 2HB monomer is key to synthesizing block copolymers, such as P(3HP)-b-P(2HB) and P(3HB-co-LMC HA)-b-P(2HB)s. The copolymers that did not contain 2HB units had a random sequence. This study’s results provide insights into the mechanism of sequence regulation by PhaCAR and pave the way for designing PHA block copolymers. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01811-7.
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Affiliation(s)
- Keigo Satoh
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Tomoya Kawakami
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Nagi Isobe
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Loïc Pasquier
- Department of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan.,Institute of Life Technologies, University of Applied Sciences and Arts Western Switzerland (HES-SO Valais-Wallis), Sion, Switzerland
| | - Hiroya Tomita
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Manfred Zinn
- Institute of Life Technologies, University of Applied Sciences and Arts Western Switzerland (HES-SO Valais-Wallis), Sion, Switzerland
| | - Ken'ichiro Matsumoto
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan.
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18
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Zhang C, Ottenheim C, Weingarten M, Ji L. Microbial Utilization of Next-Generation Feedstocks for the Biomanufacturing of Value-Added Chemicals and Food Ingredients. Front Bioeng Biotechnol 2022; 10:874612. [PMID: 35480982 PMCID: PMC9035589 DOI: 10.3389/fbioe.2022.874612] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 03/14/2022] [Indexed: 12/04/2022] Open
Abstract
Global shift to sustainability has driven the exploration of alternative feedstocks beyond sugars for biomanufacturing. Recently, C1 (CO2, CO, methane, formate and methanol) and C2 (acetate and ethanol) substrates are drawing great attention due to their natural abundance and low production cost. The advances in metabolic engineering, synthetic biology and industrial process design have greatly enhanced the efficiency that microbes use these next-generation feedstocks. The metabolic pathways to use C1 and C2 feedstocks have been introduced or enhanced into industrial workhorses, such as Escherichia coli and yeasts, by genetic rewiring and laboratory evolution strategies. Furthermore, microbes are engineered to convert these low-cost feedstocks to various high-value products, ranging from food ingredients to chemicals. This review highlights the recent development in metabolic engineering, the challenges in strain engineering and bioprocess design, and the perspectives of microbial utilization of C1 and C2 feedstocks for the biomanufacturing of value-added products.
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Affiliation(s)
- Congqiang Zhang
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- *Correspondence: Congqiang Zhang, ,
| | - Christoph Ottenheim
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Melanie Weingarten
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - LiangHui Ji
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore
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19
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Yan X, Liu X, Yu LP, Wu F, Jiang XR, Chen GQ. Biosynthesis of diverse α,ω-diol-derived polyhydroxyalkanoates by engineered Halomonas bluephagenesis. Metab Eng 2022; 72:275-288. [DOI: 10.1016/j.ymben.2022.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/07/2022] [Accepted: 04/09/2022] [Indexed: 01/08/2023]
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20
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Yoon J, Oh MK. Strategies for Biosynthesis of C1 Gas-derived Polyhydroxyalkanoates: A review. BIORESOURCE TECHNOLOGY 2022; 344:126307. [PMID: 34767907 DOI: 10.1016/j.biortech.2021.126307] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 06/13/2023]
Abstract
Biosynthesis of polyhydroxyalkanoates (PHAs) from C1 gases is highly desirable in solving problems such as climate change and microplastic pollution. PHAs are biopolymers synthesized in microbial cells and can be used as alternatives to petroleum-based plastics because of their biodegradability. Because 50% of the cost of PHA production is due to organic carbon sources and salts, the utilization of costless C1 gases as carbon sources is expected to be a promising approach for PHA production. In this review, strategies for PHA production using C1 gases through fermentation and metabolic engineering are discussed. In particular, autotrophs, acetogens, and methanotrophs are strains that can produce PHA from CO2, CO, and CH4. In addition, integrated bioprocesses for the efficient utilization of C1 gases are introduced. Biorefinery processes from C1 gas into bioplastics are prospective strategies with promising potential and feasibility to alleviate environmental issues.
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Affiliation(s)
- Jihee Yoon
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Min-Kyu Oh
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea.
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21
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22
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Jo SY, Son J, Sohn YJ, Lim SH, Lee JY, Yoo JI, Park SY, Na JG, Park SJ. A shortcut to carbon-neutral bioplastic production: Recent advances in microbial production of polyhydroxyalkanoates from C1 resources. Int J Biol Macromol 2021; 192:978-998. [PMID: 34656544 DOI: 10.1016/j.ijbiomac.2021.10.066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/04/2021] [Accepted: 10/09/2021] [Indexed: 12/18/2022]
Abstract
Since the 20th century, plastics that are widely being used in general life and industries are causing enormous plastic waste problems since improperly discarded plastics barely degrade and decompose. Thus, the demand for polyhydroxyalkanoates (PHAs), biodegradable polymers with material properties similar to conventional petroleum-based plastics, has been increased so far. The microbial production of PHAs is an environment-friendly solution for the current plastic crisis, however, the carbon sources for the microbial PHA production is a crucial factor to be considered in terms of carbon-neutrality. One‑carbon (C1) resources, such as methane, carbon monoxide, and carbon dioxide, are greenhouse gases and are abundantly found in nature and industry. C1 resources as the carbon sources for PHA production have a completely closed carbon loop with much advances; i) fast carbon circulation with direct bioconversion process and ii) simple fermentation procedure without sterilization as non-preferable nutrients. This review discusses the biosynthesis of PHAs based on C1 resource utilization by wild-type and metabolically engineered microbial host strains via biorefinery processes.
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Affiliation(s)
- Seo Young Jo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - 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
| | - Yu Jung Sohn
- 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
| | - 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
| | - 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
| | - Se Young Park
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Jeong-Geol Na
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, 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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23
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Chavan S, Yadav B, Tyagi RD, Drogui P. A review on production of polyhydroxyalkanoate (PHA) biopolyesters by thermophilic microbes using waste feedstocks. BIORESOURCE TECHNOLOGY 2021; 341:125900. [PMID: 34523565 DOI: 10.1016/j.biortech.2021.125900] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/31/2021] [Accepted: 09/03/2021] [Indexed: 05/26/2023]
Abstract
Polyhydroxyalkanoates (PHAs) are produced by numerous microbes as a subcellular energy source. Despite of their diverse applications, exorbitant production cost limits their commercial synthesis. Apart from various cost determining factors such as cost-effective feedstocks or economic recovery methods, the use of appropriate bacteria holds the key to reduce the fermentation economics. Extremophiles, especially thermophilic PHA producers, could make the bioprocess economically viable by reducing the production cost in several aspects. Using variety of waste feedstocks as carbon substrates could open the way for the valorisation of industrial waste streams and cost-effective PHA production. Therefore, the article critically reviews the current knowledge of the synthesis of PHA polyesters in thermophilic conditions. Additionally, it summarises several studies on thermophilic PHA producing bacteria grown on various waste substrates. To conclude, the paper focuses on screening and recovery methods as well as technical challenges in thermophilic PHA production.
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Affiliation(s)
- Shraddha Chavan
- INRS Eau, Terre et Environnement, 490, rue de la Couronne, Québec G1K 9A9, Canada
| | - Bhoomika Yadav
- INRS Eau, Terre et Environnement, 490, rue de la Couronne, Québec G1K 9A9, Canada
| | - R D Tyagi
- School of Technology, Huzhou University, China; BOSK-Bioproducts, 100-399 rue Jacquard, Québec (QC) G1N 4J6, Canada.
| | - Patrick Drogui
- INRS Eau, Terre et Environnement, 490, rue de la Couronne, Québec G1K 9A9, Canada
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Glaskova-Kuzmina T, Starkova O, Gaidukovs S, Platnieks O, Gaidukova G. Durability of Biodegradable Polymer Nanocomposites. Polymers (Basel) 2021; 13:3375. [PMID: 34641189 PMCID: PMC8512741 DOI: 10.3390/polym13193375] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 11/23/2022] Open
Abstract
Biodegradable polymers (BP) are often regarded as the materials of the future, which address the rising environmental concerns. The advancement of biorefineries and sustainable technologies has yielded various BP with excellent properties comparable to commodity plastics. Water resistance, high dimensional stability, processability and excellent physicochemical properties limit the reviewed materials to biodegradable polyesters and modified compositions of starch and cellulose, both known for their abundance and relatively low price. The addition of different nanofillers and preparation of polymer nanocomposites can effectively improve BP with controlled functional properties and change the rate of degradation. The lack of data on the durability of biodegradable polymer nanocomposites (BPN) has been the motivation for the current review that summarizes recent literature data on environmental ageing of BPN and the role of nanofillers, their basic engineering properties and potential applications. Various durability tests discussed thermal ageing, photo-oxidative ageing, water absorption, hygrothermal ageing and creep testing. It was discussed that incorporating nanofillers into BP could attenuate the loss of mechanical properties and improve durability. Although, in the case of poor dispersion, the addition of the nanofillers can lead to even faster degradation, depending on the structural integrity and the state of interfacial adhesion. Selected models that describe the durability performance of BPN were considered in the review. These can be applied as a practical tool to design BPN with tailored property degradationand durability.
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Affiliation(s)
| | - Olesja Starkova
- Institute for Mechanics of Materials, University of Latvia, LV-1004 Riga, Latvia;
| | - Sergejs Gaidukovs
- Institute of Polymer Materials, Faculty of Materials Science and Applied Chemistry, Riga Technical University, P.Valdena 3/7, LV-1048 Riga, Latvia; (S.G.); (O.P.)
| | - Oskars Platnieks
- Institute of Polymer Materials, Faculty of Materials Science and Applied Chemistry, Riga Technical University, P.Valdena 3/7, LV-1048 Riga, Latvia; (S.G.); (O.P.)
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Nguyen TT, Lee EY. Methane-based biosynthesis of 4-hydroxybutyrate and P(3-hydroxybutyrate-co-4-hydroxybutyrate) using engineered Methylosinus trichosporium OB3b. BIORESOURCE TECHNOLOGY 2021; 335:125263. [PMID: 34020156 DOI: 10.1016/j.biortech.2021.125263] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/05/2021] [Accepted: 05/06/2021] [Indexed: 06/12/2023]
Abstract
4-Hydroxybutyric acid (4-HB) is a key platform chemical that serves as a precursor in a wide variety of industrial applications including 1,4-butanediol and bioplastics production. In this study, we reconstructed 4-HB biosynthetic pathway including CoA-dependent succinate semialdehyde dehydrogenase and NADPH-dependent succinate semialdehyde reductase in Type II methanotrophs, Methylosinus trichosporium OB3b, to synthesize 4-HB. These engineered strains were able to synthesize 4-HB from methane via tricarboxylic acid cycle. 4-HB synthesis was further improved to 10.5 mg/L by overexpressing phosphoenolpyruvate carboxylase, isocitrate dehydrogenase and 2-oxoglutarate dehydrogenase genes in M. trichosporium OB3b. We combined the native poly(3-hydroxybutyrate) metabolic pathway and reconstructed 4-HB biosynthetic pathway to synthesize P(3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer from structurally unrelated substrate methane as a single carbon source. These engineered strains could synthesize P(3HB-co-4HB) copolymer with 3.08 mol% 4-HB from methane. This study provides several engineering strategies to synthesize polyhydroxyalkanoates and their monomers from methane.
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Affiliation(s)
- Thu Thi Nguyen
- Department of Chemical Engineering (Integrated Engineering), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (Integrated Engineering), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
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Huong KH, Sevakumaran V, Amirul AA. P(3HB- co-4HB) as high value polyhydroxyalkanoate: its development over recent decades and current advances. Crit Rev Biotechnol 2021; 41:474-490. [PMID: 33726581 DOI: 10.1080/07388551.2020.1869685] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Polyhydroxyalkanoate (PHA) is a biogenic polymer that has the potential to substitute synthetic plastic in numerous applications. This is due to its unique attribute of being a biodegradable and biocompatible thermoplastic, achievable through microbial fermentation from a broad utilizable range of renewable resources. Among all the PHAs discovered, poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] stands out as a next generation healthcare biomaterial for having high biopharmaceutical and medical value since it is highly compatible to mammalian tissue. This review provides a critical assessment and complete overview of the development and trend of P(3HB-co-4HB) research over the last few decades, highlighting aspects from the microbial strain discovery to metabolic engineering and bioprocess cultivation strategies. The article also outlines the relevance of P(3HB-co-4HB) as a material for high value-added products in numerous healthcare-related applications.
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Affiliation(s)
- Kai-Hee Huong
- School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia
| | - Vigneswari Sevakumaran
- Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, Kuala Nerus, Kuala Terengganu, Terengganu, Malaysia
| | - A A Amirul
- School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia.,Centre for Chemical Biology, Universiti Sains Malaysia, Bayan Lepas, Penang, Malaysia.,Malaysian Institute of Pharmaceuticals and Nutraceuticals, NIBM, Gelugor, Penang, Malaysia
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Yoon J, Chang W, Oh SH, Choi SH, Yang YH, Oh MK. Metabolic engineering of Methylorubrum extorquens AM1 for poly (3-hydroxybutyrate-co-3-hydroxyvalerate) production using formate. Int J Biol Macromol 2021; 177:284-293. [PMID: 33610606 DOI: 10.1016/j.ijbiomac.2021.02.092] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 02/04/2021] [Accepted: 02/12/2021] [Indexed: 10/22/2022]
Abstract
Formate is a promising environmentally friendly and sustainable feedstock synthesized from syngas or carbon dioxide. Methylorubrum extorquens is a type II methylotroph that can use formate as a carbon source. It accumulates polyhydroxyalkanoates (PHAs) inside the cell, mainly producing poly-3-hydroxybutyrate (PHB), a degradable biopolymer. Owing to its high melting point and stiff nature, however, mechanical property improvement is warranted in the form of copolymerization. To produce the PHA copolymer, poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), the endogenous gene phaC was deleted and the pathway genes bktB, phaJ1, and phaC2, with broader substrate specificities, were heterologously expressed. To improve the incorporation of 3-hydroxyvalerate (3HV), the expression level of bktB was improved by untranslated region (UTR) engineering, and the endogenous gene phaA was deleted. The engineered M. extorquens produced PHBV with 8.9% 3HV using formate as the sole carbon source. In addition, when propionate and butyrate were supplemented, PHBVs with 3HV portions of up to 70.6% were produced. This study shows that a PHBV copolymer with a high proportion of 3HV can be synthesized using formate, a C1 carbon source, through metabolic engineering and supplementation with short-chain fatty acids.
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Affiliation(s)
- Jihee Yoon
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Woojin Chang
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Seung-Hwan Oh
- Department of Chemical Engineering, Hongik University, Mapo-gu, Seoul 04066, Republic of Korea
| | - Soo-Hyung Choi
- Department of Chemical Engineering, Hongik University, Mapo-gu, Seoul 04066, Republic of Korea
| | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | - Min-Kyu Oh
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea.
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Jawaharraj K, Shrestha N, Chilkoor G, Dhiman SS, Islam J, Gadhamshetty V. Valorization of methane from environmental engineering applications: A critical review. WATER RESEARCH 2020; 187:116400. [PMID: 32979578 DOI: 10.1016/j.watres.2020.116400] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 07/29/2020] [Accepted: 09/05/2020] [Indexed: 05/09/2023]
Abstract
Wastewater and waste management sectors alone account for 18% of the anthropogenic methane (CH4) emissions. This study presents a critical overview of methanotrophs ("methane oxidizing microorganisms") for valorizing typically discarded CH4 from environmental engineering applications, focusing on wastewater treatment plants. Methanotrophs can convert CH4 into valuable bioproducts including chemicals, biodiesel, DC electricity, polymers, and S-layers, all under ambient conditions. As discarded CH4 and its oxidation products can also be used as a carbon source in nitrification and annamox processes. Here we discuss modes of CH4 assimilation by methanotrophs in both natural and engineered systems. We also highlight the technical challenges and technological breakthroughs needed to enable targeted CH4 oxidation in wastewater treatment plants.
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Affiliation(s)
- Kalimuthu Jawaharraj
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States
| | - Namita Shrestha
- Civil and Environmental Engineering, Rose-Hulman Institute of Technology, Terre Haute 47803, IN, United States
| | - Govinda Chilkoor
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, Rapid City 57701, SD, United States
| | - Saurabh Sudha Dhiman
- BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States; Biological and Chemical Engineering, South Dakota School of Mines & Technology, Rapid City 57701, SD, United States
| | - Jamil Islam
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States
| | - Venkataramana Gadhamshetty
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, Rapid City 57701, SD, United States.
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Rodríguez Y, Firmino PIM, Pérez V, Lebrero R, Muñoz R. Biogas valorization via continuous polyhydroxybutyrate production by Methylocystis hirsuta in a bubble column bioreactor. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 113:395-403. [PMID: 32585559 DOI: 10.1016/j.wasman.2020.06.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/25/2020] [Accepted: 06/11/2020] [Indexed: 06/11/2023]
Abstract
Creating additional value out of biogas during waste treatment has become a priority in past years. Biogas bioconversion into valuable bioproducts such as biopolymers has emerged as a promising strategy. This work assessed the operational feasibility of a bubble column bioreactor (BCB) implemented with gas recirculation and inoculated with a polyhydroxybutyrate (PHB)-producing strain using biogas as substrate. The BCB was initially operated at empty bed residence times (EBRTs) ranging from 30 to 120 min and gas recirculation ratios (R) from 0 to 30 to assess the gas-to-liquid mass transfer and bioconversion of CH4. Subsequently, the BCB was continuously operated at a R of 30 and an EBRT of 60 min under excess of nitrogen and nitrogen feast-famine cycles of 24 h:24 h to trigger PHB synthesis. Gas recirculation played a major role in CH4 gas-liquid transfer, providing almost fourfold higher CH4 elimination capacities (~41 g CH4 m-3 h-1) at the highest R and EBRT of 60 min. The long-term operation under N excess conditions entailed nitrite accumulation (induced by O2 limiting conditions) and concurrent methanotrophic activity inhibition above ~60 mg N-NO2- L-1. Adjusting the N-NO3- supply to match microbial N demand successfully prevented nitrite accumulation. Finally, the N feast-famine 24 h:24 h strategy supported a stable CH4 conversion with a removal efficiency of 70% along with a continuous PHB production, which yielded PHB accumulations of 14.5 ± 2.9% (mg PHB mg-1 total suspended solids × 100). These outcomes represent the first step towards the integration of biogas biorefineries into conventional anaerobic digestion plants.
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Affiliation(s)
- Yadira Rodríguez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Paulo Igor Milen Firmino
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Víctor Pérez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raquel Lebrero
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raúl Muñoz
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain.
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Balakrishna Pillai A, Jaya Kumar A, Kumarapillai H. Biosynthesis of poly(3-hydroxybutyrate- co-3-hydroxyvalerate) (PHBV) in Bacillus aryabhattai and cytotoxicity evaluation of PHBV/poly(ethylene glycol) blends. 3 Biotech 2020; 10:32. [PMID: 31988826 PMCID: PMC6946779 DOI: 10.1007/s13205-019-2017-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 12/16/2019] [Indexed: 01/25/2023] Open
Abstract
The study described poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) accumulation in Bacillus aryabhattai PHB10 for the first time and evaluated the polymer induced cytotoxicity in-vitro with PHBV/poly(ethylene glycol) (PEG) blends. The B. aryabhattai strain produced 2.8 g/L PHBV, equivalent to 71.15% of cell dry mass in a medium supplemented with propionic acid, after 48 h incubation. The optimum temperature and pH for the copolymer accumulation was 31 °C and 7, respectively. The gas chromatography-mass spectrometry and nuclear magnetic resonance analyses confirmed the polymer obtained as PHBV. The differential scanning calorimetry analysis revealed that the melting point of the material as 90 °C and its thermal stability up to 220 °C. The average molecular weight (Mn) and polydispersity index of the sample was estimated by gel permeation chromatography analysis and observed as 128.508 kDa and 2.82, respectively. The PHBV showed tensile strength of 10.3 MPa and elongation at break of 13.3%. The PHBV and their blends with PEG were tested for cytotoxicity on human keratinocytes (HaCaT cells) and the cells incubated with PHBV/PEG2kDa blends were 99% viable, whereas with the PHBV alone showed comparatively higher cytotoxicity. The significant improvement in the cell viability of PHBV/PEG2kDa blends indicates its potential as a candidate for skin graft applications.
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Affiliation(s)
- Aneesh Balakrishna Pillai
- Environmental Biology Laboratory, Rajiv Gandhi Centre for Biotechnology, Thycaud P. O., Thiruvananthapuram, Kerala 695014 India
| | - Arjun Jaya Kumar
- Environmental Biology Laboratory, Rajiv Gandhi Centre for Biotechnology, Thycaud P. O., Thiruvananthapuram, Kerala 695014 India
| | - Harikrishnan Kumarapillai
- Environmental Biology Laboratory, Rajiv Gandhi Centre for Biotechnology, Thycaud P. O., Thiruvananthapuram, Kerala 695014 India
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Luangthongkam P, Strong PJ, Syed Mahamud SN, Evans P, Jensen P, Tyson G, Laycock B, Lant PA, Pratt S. The effect of methane and odd-chain fatty acids on 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) synthesis by a Methylosinus-dominated mixed culture. BIORESOUR BIOPROCESS 2019. [DOI: 10.1186/s40643-019-0285-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractA methanotrophic community was enriched in a semi-continuous reactor under non-aseptic conditions with methane and ammonia as carbon and nitrogen source. After a year of operation, Methylosinus sp., accounted for 80% relative abundance of the total sequences identified from potential polyhydroxyalkanoates (PHAs) producers, dominated the methane-fed enrichment. Prior to induction of PHA accumulation, cells harvested from the parent reactor contained low level of PHA at 4.0 ± 0.3 wt%. The cells were later incubated in the absence of ammonia with various combinations of methane, propionic acid, and valeric acid to induce biosynthesis of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Previous studies reported that methanotrophic utilization of odd-chain fatty acids for the production of PHAs requires reducing power from methane oxidation. However, our findings demonstrated that the PHB-containing methanotrophic enrichment does not require methane availability to generate 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV)—when odd-chain fatty acids are presented. The enrichment yielded up to 14 wt% PHA with various mole fractions of 3HV monomer depending on the availability of methane and odd-fatty acids. Overall, the addition of valeric acid resulted in a higher PHA content and a higher 3HV fraction. The highest 3HV fraction (up to 65 mol%) was obtained from the methane–valeric acid experiment, which is higher than those previously reported for PHA-producing methanotrophic mixed microbial cultures.
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Rao A, Haque S, El-Enshasy HA, Singh V, Mishra BN. RSM-GA Based Optimization of Bacterial PHA Production and In Silico Modulation of Citrate Synthase for Enhancing PHA Production. Biomolecules 2019; 9:biom9120872. [PMID: 31842491 PMCID: PMC6995514 DOI: 10.3390/biom9120872] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/27/2019] [Accepted: 12/02/2019] [Indexed: 12/23/2022] Open
Abstract
The inexhaustible nature and biodegradability of bioplastics like polyhydroxyalkanoates (PHAs) make them suitable assets to replace synthetic plastics. The eventual fate of these eco-friendly and non-toxic bioplastics relies upon the endeavors towards satisfying cost and, in addition, execution necessity. In this study, we utilized and statistically optimized different food (kitchen-/agro-) waste as a sole carbon/nitrogen source for the production of PHA at a reduced cost, indicating a proficient waste administration procedure. Seven different types of kitchen-/agro-waste were used as unique carbon source and four different types of nitrogen source were used to study their impact on PHA production by Bacillus subtilis MTCC 144. Among four different studied production media, mineral salt medium (MSM) (biomass: 37.7 g/L; cell dry weight: 1.8 g/L; and PHA: 1.54 g/L) was found most suitable for PHA production. Further, carbon and nitrogen components of MSM were optimized using one-factor-at-a-time experiments, and found that watermelon rind (PHA = 12.97 g/L) and pulse peel (PHA = 13.5 g/L) were the most suitable carbon and nitrogen sources, respectively, in terms of PHA (78.60%) recovery. The concentrations of these factors (sources) were statistically optimized using response surface methodology coupled with the genetic algorithm approach. Additionally, in order to enhance microbial PHA production, the interaction of citrate synthase, a key enzyme in the TCA cycle, with different known inhibitors was studied using in silico molecular docking approach. The inhibition of citrate synthase induces the blockage of the tricarboxylic cycle (TCA), thereby increasing the concentration of acetyl-CoA that helps in enhanced PHA production. Molecular docking of citrate synthase with different inhibitors of PubChem database revealed that hesperidin (PubChem compound CID ID 10621), generally present in citrus fruits, is the most efficient inhibitor of the TCA cycle with the binding score of –11.4 and warrants experimental validation. Overall, this study provides an efficient food waste management approach by reducing the production cost and enhancing the production of PHA, thereby lessening our reliance on petroleum-based plastics.
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Affiliation(s)
- Apoorva Rao
- Department of Biotechnology, Institute of Engineering and Technology, Dr. A.P.J. Abdul Kalam Technical University, Lucknow, Sitapur Road, Lucknow 226021, Uttar Pradesh, India;
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan 45142, Saudi Arabia;
| | - Hesham A. El-Enshasy
- Institute of Bioproduct Development (IBD), Universiti Teknologi Malaysia (UTM), Skudai, Johor Bahru 81310, Malaysia;
- School of Chemical Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Skudai, Johor Bahru 81310, Malaysia
- City of Scientific Research and Technological Applications, New Burg Al Arab 21934, Alexandria, Egypt
| | - Vineeta Singh
- Department of Biotechnology, Institute of Engineering and Technology, Dr. A.P.J. Abdul Kalam Technical University, Lucknow, Sitapur Road, Lucknow 226021, Uttar Pradesh, India;
- Correspondence: (V.S.); (B.N.M.); Tel.: +91-522-2361692 (V.S.); +91-522-2361631 (B.N.M.)
| | - Bhartendu Nath Mishra
- Department of Biotechnology, Institute of Engineering and Technology, Dr. A.P.J. Abdul Kalam Technical University, Lucknow, Sitapur Road, Lucknow 226021, Uttar Pradesh, India;
- Correspondence: (V.S.); (B.N.M.); Tel.: +91-522-2361692 (V.S.); +91-522-2361631 (B.N.M.)
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Kumar V, Kumar S, Singh D. Microbial polyhydroxyalkanoates from extreme niches: Bioprospection status, opportunities and challenges. Int J Biol Macromol 2019; 147:1255-1267. [PMID: 31739043 DOI: 10.1016/j.ijbiomac.2019.09.253] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 09/23/2019] [Accepted: 09/30/2019] [Indexed: 01/20/2023]
Abstract
Extreme niches are offered with unusual physiochemical conditions that impose stress to the life-forms including microbial communities. Microbes have evolved unique physiology and genetics to interact dynamically with extreme environments for their adaptation and survival. Amongst the several adaptive features of microbes in stressed conditions, polyhydroxyalkanoates synthesis is a crucial strategy of many bacteria and archaea to reserve carbon and energy inside the cell. Apart from the relevance of PHA to microbial world, these intracellular polyesters are seen as essential biological macromolecules for the bio-material industry owing to their plastic-like properties, biodegradable and eco-friendly nature. Recently, much attention has been attracted by the microbes of extreme habitats for a new source of industrially suited PHA producers and novel PHA with unique properties. Therefore, the current review is focused on the critical evaluation of microbes from extreme niches for PHA production and opportunities for the development of commercially feasible PHA bioprocess.
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Affiliation(s)
- Vijay Kumar
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India
| | - Sanjay Kumar
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India
| | - Dharam Singh
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India.
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Luangthongkam P, Laycock B, Evans P, Lant P, Pratt S. Thermophilic production of poly(3-hydroxybutyrate-co-3-hydrovalerate) by a mixed methane-utilizing culture. N Biotechnol 2019; 53:49-56. [PMID: 31276815 DOI: 10.1016/j.nbt.2019.06.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 06/23/2019] [Accepted: 06/30/2019] [Indexed: 11/24/2022]
Abstract
The production of polyhydroxyalkanoates (PHAs) from methane is limited to mesophiles and thus suffers from high energy requirements for cooling. To address this issue, the use of thermophilic processes is gaining interest, as this strategy may deliver improved economic feasibility for PHA production. This study reports the first thermophilic PHA-producing culture grown on methane at 55 °C in fill-and-draw batch reactors. Harvested cells were incubated with various combinations of methane, propionic acid and valeric acid to assess their capacity for the synthesis of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Only PHB was produced when fed with methane alone. The addition of odd-carbon-number fatty acids resulted in higher PHA content with 3 HV fractions in the range of 15-99 mol%, depending on the types of fatty acids added. Acetic acid addition enhanced the synthesis of 3HB monomer, but not of 3 HV. On increasing the temperature to 58 °C, PHA productivity was not significantly affected.
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Affiliation(s)
- Pawarisa Luangthongkam
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland, 4072, Australia
| | - Bronwyn Laycock
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland, 4072, Australia
| | - Paul Evans
- The Australian Centre for Ecogenomics (ACE), The University of Queensland, St. Lucia, Brisbane, Queensland, 4072, Australia
| | - Paul Lant
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland, 4072, Australia
| | - Steven Pratt
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland, 4072, Australia.
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36
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El Abbadi SH, Criddle CS. Engineering the Dark Food Chain. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:2273-2287. [PMID: 30640466 DOI: 10.1021/acs.est.8b04038] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Meeting global food needs in the face of climate change and resource limitation requires innovative approaches to food production. Here, we explore incorporation of new dark food chains into human food systems, drawing inspiration from natural ecosystems, the history of single cell protein, and opportunities for new food production through wastewater treatment, microbial protein production, and aquaculture. The envisioned dark food chains rely upon chemoautotrophy in lieu of photosynthesis, with primary production based upon assimilation of CH4 and CO2 by methane- and hydrogen-oxidizing bacteria. The stoichiometry, kinetics, and thermodynamics of these bacteria are evaluated, and opportunities for recycling of carbon, nitrogen, and water are explored. Because these processes do not require light delivery, high volumetric productivities are possible; because they are exothermic, heat is available for downstream protein processing; because the feedstock gases are cheap, existing pipeline infrastructure could facilitate low-cost energy-efficient delivery in urban environments. Potential life-cycle benefits include: a protein alternative to fishmeal; partial decoupling of animal feed from human food; climate change mitigation due to decreased land use for agriculture; efficient local cycling of carbon and nutrients that offsets the need for energy-intensive fertilizers; and production of high value products, such as the prebiotic polyhydroxybutyrate.
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Affiliation(s)
- Sahar H El Abbadi
- Department of Civil and Environmental Engineering , Stanford University , Stanford , California 94305-4020 , United States
| | - Craig S Criddle
- Department of Civil and Environmental Engineering , Stanford University , Stanford , California 94305-4020 , United States
- William and Cloy Codiga Resource Recovery Center , Stanford University , Stanford , California 94305-4020 , United States
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Bio-conversion of methane into high profit margin compounds: an innovative, environmentally friendly and cost-effective platform for methane abatement. World J Microbiol Biotechnol 2019; 35:16. [PMID: 30617555 DOI: 10.1007/s11274-018-2587-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 12/31/2018] [Indexed: 01/04/2023]
Abstract
Despite the environmental relevance of CH4 and forthcoming stricter regulations, the development of cost-efficient and environmentally friendly technologies for CH4 abatement is still limited. To date, one of the most promising solutions for the mitigation of this important GHG consists of the bioconversion of CH4 into bioproducts with a high profit margin. In this context, methanotrophs have been already proven as cell-factories of some of the most expensive products synthesized by microorganisms. In the case of ectoine (1000 $ kg-1), already described methanotrophic genera such as Methylomicrobium can accumulate up to 20% (ectoine wt-1) using methane as the only carbon source. Moreover, α-methanotrophs, such as Methylosynus and Methylocystis, are able to store bioplastic concentrations up to 50-60% of their total cell content. More than that, methanotrophs are one of the greatest potential producers of methanol and exopolysaccharides. Although this methanotrophic factory could be enhanced throughout metabolic engineering, the valorization of CH4 into valuable metabolites has been already consistently demonstrated under continuous and discontinuous mode, producing more than one compound in the same bioprocess, and using both, single strains and specific consortia. This review states the state-of-the-art of this innovative biotechnological platform by assessing its potential and current limitations.
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Fergala A, AlSayed A, Khattab S, Ramirez M, Eldyasti A. Development of Methane-Utilizing Mixed Cultures for the Production of Polyhydroxyalkanoates (PHAs) from Anaerobic Digester Sludge. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:12376-12387. [PMID: 30339372 DOI: 10.1021/acs.est.8b04142] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The fundamental components required for scaling up the production of biogas-based biopolymers can be provided through a single process, that is, anaerobic digestion (AD). In this research, the possibility of enriching methane-utilizing mixed cultures from the AD process was explored as well as their capability to accumulate polyhydroxyalkanoates (PHAs). For almost 70 days of operation in a fed-batch cyclic mode, the specific growth rate was 0.078 ± 0.005 h-1 and the biomass yield was 0.7 ± 0.08 mg-VSS/mg-CH4. Adjusting the nitrogen levels in AD centrate resulted in results comparable to those obtained with a synthetic medium. The enriched culture could accumulate up to 51 ± 2% PHB. On the other hand, when the culturing medium was supplemented with valeric acid, the enriched bacteria were able to produce polyhydroxybutyrate- co-valerate (PHBV) up to 52 ± 6% with an HV percentage of 33 ± 5%. Increasing the valeric acid concentration in the culturing medium above 100 mg/L decreased the overall amount of PHBV by 60%, whereas the number of HV units incorporated was not affected. Changing the methane-to-oxygen ratio (M/O) from 1:1 to 4:1 caused an almost 80% decline in PHB accumulation. In addition, M/O had a significant effect on the fraction composition of PHBV at different valeric acid concentrations.
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Affiliation(s)
- Ahmed Fergala
- Department of Civil Engineering, Lassonde School of Engineering , York University , Toronto , Ontario Canada M3J 1P3
| | - Ahmed AlSayed
- Department of Civil Engineering, Lassonde School of Engineering , York University , Toronto , Ontario Canada M3J 1P3
| | - Saif Khattab
- Department of Chemical Engineering , Ryerson University , 350 Victoria Street , Toronto , Ontario Canada M5B 2K3
| | - Megan Ramirez
- Department of Environmental Engineering , Universidad International , Cuernavaca , Morelos , Mexico
| | - Ahmed Eldyasti
- Department of Civil Engineering, Lassonde School of Engineering , York University , Toronto , Ontario Canada M3J 1P3
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Technologies for the bioconversion of methane into more valuable products. Curr Opin Biotechnol 2018; 50:128-135. [PMID: 29316497 DOI: 10.1016/j.copbio.2017.12.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 12/19/2017] [Accepted: 12/20/2017] [Indexed: 11/22/2022]
Abstract
Methane, with a global warming potential twenty five times higher than that of CO2 is the second most important greenhouse gas emitted nowadays. Its bioconversion into microbial molecules with a high retail value in the industry offers a potential cost-efficient and environmentally friendly solution for mitigating anthropogenic diluted CH4-laden streams. Methane bio-refinery for the production of different compounds such as ectoine, feed proteins, biofuels, bioplastics and polysaccharides, apart from new bioproducts characteristic of methanotrophic bacteria, has been recently tested in discontinuous and continuous bioreactors with promising results. This review constitutes a critical discussion about the state-of-the-art of the potential and research niches of biotechnologies applied in a CH4 biorefinery approach.
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