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Asif A, Koner S, Chen JS, Hussain A, Huang SW, Hussain B, Hsu BM. Uncovering the microbial community structure and physiological profiles of terrestrial mud volcanoes: a comprehensive metagenomic insight towards their Trichloroethylene biodegradation potentiality. ENVIRONMENTAL RESEARCH 2024:119457. [PMID: 38906444 DOI: 10.1016/j.envres.2024.119457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 06/04/2024] [Accepted: 06/18/2024] [Indexed: 06/23/2024]
Abstract
Mud volcanoes are dynamic geological features releasing methane (CH4), carbon dioxide (CO2), and hydrocarbons, harboring diverse methane and hydrocarbon-degrading microbes. However, the potential application of these microbial communities in chlorinated hydrocarbons bioremediation purposes such as trichloroethylene (TCE) has not yet been explored. Hence, this study investigated the mud volcano's microbial diversity functional potentiality in TCE degradation as well as their eco-physiological profiling using metabolic activity. Geochemical analysis of the mud volcano samples revealed variations in pH, temperature, and oxidation-reduction potential, indicating diverse environmental conditions. The Biolog Ecoplate™ carbon substrates utilization pattern showed that the Tween 80 was highly consumed by mud volcanic microbial community. Similarly, MicroResp® analysis results demonstrated that presence of additive C-substrates condition might enhanced the cellular respiration process within mud-volcanic microbial community. Full-length 16S rRNA sequencing identified Proteobacteria as the dominant phylum, with genera like Pseudomonas and Hydrogenophaga associated with chloroalkane degradation, and methanotrophic bacteria such as Methylomicrobium and Methylophaga linked to methane oxidation. Functional analysis uncovered diverse metabolic functions, including sulfur and methane metabolism and hydrocarbon degradation, with specific genes involved in methane oxidation and sulfur metabolism. These findings provide insights into the microbial diversity and metabolic capabilities of mud volcano ecosystems, which could facilitate their effective application in the bioremediation of chlorinated compounds.
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Affiliation(s)
- Aslia Asif
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan; Doctoral Program in Science, Technology, Environment, and Mathematics, National Chung Cheng University, Chiayi County, Taiwan
| | - Suprokash Koner
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan
| | - Jung-Sheng Chen
- Department of Medical Research, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Ashiq Hussain
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan; Doctoral Program in Science, Technology, Environment, and Mathematics, National Chung Cheng University, Chiayi County, Taiwan
| | - Shih-Wei Huang
- Center for Environmental Toxin and Emerging Contaminant, Cheng Shiu University, Kaohsiung, Taiwan; Institute of Environmental Toxin and Emerging Contaminant, Cheng Shiu University, Kaohsiung, Taiwan
| | - Bashir Hussain
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan
| | - Bing-Mu Hsu
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan.
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2
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Samanta D, Rauniyar S, Saxena P, Sani RK. From genome to evolution: investigating type II methylotrophs using a pangenomic analysis. mSystems 2024; 9:e0024824. [PMID: 38695578 DOI: 10.1128/msystems.00248-24] [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: 02/19/2024] [Accepted: 04/04/2024] [Indexed: 06/19/2024] Open
Abstract
A comprehensive pangenomic approach was employed to analyze the genomes of 75 type II methylotrophs spanning various genera. Our investigation revealed 256 exact core gene families shared by all 75 organisms, emphasizing their crucial role in the survival and adaptability of these organisms. Additionally, we predicted the functionality of 12 hypothetical proteins. The analysis unveiled a diverse array of genes associated with key metabolic pathways, including methane, serine, glyoxylate, and ethylmalonyl-CoA (EMC) metabolic pathways. While all selected organisms possessed essential genes for the serine pathway, Methylooceanibacter marginalis lacked serine hydroxymethyltransferase (SHMT), and Methylobacterium variabile exhibited both isozymes of SHMT, suggesting its potential to utilize a broader range of carbon sources. Notably, Methylobrevis sp. displayed a unique serine-glyoxylate transaminase isozyme not found in other organisms. Only nine organisms featured anaplerotic enzymes (isocitrate lyase and malate synthase) for the glyoxylate pathway, with the rest following the EMC pathway. Methylovirgula sp. 4MZ18 stood out by acquiring genes from both glyoxylate and EMC pathways, and Methylocapsa sp. S129 featured an A-form malate synthase, unlike the G-form found in the remaining organisms. Our findings also revealed distinct phylogenetic relationships and clustering patterns among type II methylotrophs, leading to the proposal of a separate genus for Methylovirgula sp. 4M-Z18 and Methylocapsa sp. S129. This pangenomic study unveils remarkable metabolic diversity, unique gene characteristics, and distinct clustering patterns of type II methylotrophs, providing valuable insights for future carbon sequestration and biotechnological applications. IMPORTANCE Methylotrophs have played a significant role in methane-based product production for many years. However, a comprehensive investigation into the diverse genetic architectures across different genera of methylotrophs has been lacking. This study fills this knowledge gap by enhancing our understanding of core hypothetical proteins and unique enzymes involved in methane oxidation, serine, glyoxylate, and ethylmalonyl-CoA pathways. These findings provide a valuable reference for researchers working with other methylotrophic species. Furthermore, this study not only unveils distinctive gene characteristics and phylogenetic relationships but also suggests a reclassification for Methylovirgula sp. 4M-Z18 and Methylocapsa sp. S129 into separate genera due to their unique attributes within their respective genus. Leveraging the synergies among various methylotrophic organisms, the scientific community can potentially optimize metabolite production, increasing the yield of desired end products and overall productivity.
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Affiliation(s)
- Dipayan Samanta
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
| | - Shailabh Rauniyar
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
| | - Priya Saxena
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
- Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
- 2-Dimensional Materials for Biofilm Engineering, Science and Technology, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
- Data Driven Material Discovery Center for Bioengineering Innovation, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
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Yu Y, Shi Y, Kwon YW, Choi Y, Kim Y, Na JG, Huh J, Lee J. A rationally designed miniature of soluble methane monooxygenase enables rapid and high-yield methanol production in Escherichia coli. Nat Commun 2024; 15:4399. [PMID: 38782897 PMCID: PMC11116448 DOI: 10.1038/s41467-024-48671-w] [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: 10/02/2023] [Accepted: 05/08/2024] [Indexed: 05/25/2024] Open
Abstract
Soluble methane monooxygenase (sMMO) oxidizes a wide range of carbon feedstocks (C1 to C8) directly using intracellular NADH and is a useful means in developing green routes for industrial manufacturing of chemicals. However, the high-throughput biosynthesis of active recombinant sMMO and the ensuing catalytic oxidation have so far been unsuccessful due to the structural and functional complexity of sMMO, comprised of three functionally complementary components, which remains a major challenge for its industrial applications. Here we develop a catalytically active miniature of sMMO (mini-sMMO), with a turnover frequency of 0.32 s-1, through an optimal reassembly of minimal and modified components of sMMO on catalytically inert and stable apoferritin scaffold. We characterise the molecular characteristics in detail through in silico and experimental analyses and verifications. Notably, in-situ methanol production in a high-cell-density culture of mini-sMMO-expressing recombinant Escherichia coli resulted in higher yield and productivity (~ 3.0 g/L and 0.11 g/L/h, respectively) compared to traditional methanotrophic production.
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Affiliation(s)
- Yeonhwa Yu
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong 5-1, Seongbuk-Gu, Seoul, 02841, Republic of Korea
| | - Yongfan Shi
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, 04107, Republic of Korea
| | - Young Wan Kwon
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Anam-Dong 5-1, Seongbuk-Gu, Seoul, 02841, Republic of Korea
| | - Yoobin Choi
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong 5-1, Seongbuk-Gu, Seoul, 02841, Republic of Korea
| | - Yusik Kim
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong 5-1, Seongbuk-Gu, Seoul, 02841, Republic of Korea
| | - Jeong-Geol Na
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, 04107, Republic of Korea
| | - June Huh
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong 5-1, Seongbuk-Gu, Seoul, 02841, Republic of Korea.
| | - Jeewon Lee
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong 5-1, Seongbuk-Gu, Seoul, 02841, Republic of Korea.
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Lienhart PH, Rohra V, Clement C, Toppen LC, DeCola AC, Rizzo DM, Scarborough MJ. Landfill intermediate cover soil microbiomes and their potential for mitigating greenhouse gas emissions revealed through metagenomics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 925:171697. [PMID: 38492594 DOI: 10.1016/j.scitotenv.2024.171697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/09/2024] [Accepted: 03/11/2024] [Indexed: 03/18/2024]
Abstract
Landfills are a major source of anthropogenic methane emissions and have been found to produce nitrous oxide, an even more potent greenhouse gas than methane. Intermediate cover soil (ICS) plays a key role in reducing methane emissions but may also result in nitrous oxide production. To assess the potential for microbial methane oxidation and nitrous oxide production, long sequencing reads were generated from ICS microbiome DNA and reads were functionally annotated for 24 samples across ICS at a large landfill in New York. Further, incubation experiments were performed to assess methane consumption and nitrous oxide production with varying amounts of ammonia supplemented. Methane was readily consumed by microbes in the composite ICS and all incubations with methane produced small amounts of nitrous oxide even when ammonia was not supplemented. Incubations without methane produced significantly less nitrous oxide than those incubated with methane. In incubations with methane added, the observed specific rate of methane consumption was 0.776 +/- 0.055 μg CH4 g dry weight (DW) soil-1 h-1 and the specific rate of nitrous oxide production was 3.64 × 10-5 +/- 1.30 × 10-5 μg N2O g DW soil-1 h-1. The methanotrophs Methylobacter and an unclassified genus within the family Methlyococcaceae were present in the original ICS samples and the incubation samples, and their abundance increased during incubations with methane. Genes encoding particulate methane monooxygenase/ ammonia monooxygenase (pMMO) were much more abundant than genes encoding soluble methane monooxygenase (sMMO) across the landfill ICS. Genes encoding proteins that convert hydroxylamine to nitrous oxide were not highly abundant in the ICS or incubation metagenomes. In total, these results suggest that although ammonia oxidation via methanotrophs may result in low levels of nitrous oxide production, ICS microbial communities have the potential to greatly reduce the overall global warming potential of landfill emissions.
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Affiliation(s)
- Peyton H Lienhart
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, VT, United States
| | - Venus Rohra
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, VT, United States
| | - Courtney Clement
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Lucinda C Toppen
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, VT, United States.
| | - Amy C DeCola
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, VT, United States
| | - Donna M Rizzo
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, VT, United States; Gund Institute for Environment, University of Vermont, Burlington, VT, United States.
| | - Matthew J Scarborough
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, VT, United States; Gund Institute for Environment, University of Vermont, Burlington, VT, United States.
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5
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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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Decembrino D, Cannella D. The thin line between monooxygenases and peroxygenases. P450s, UPOs, MMOs, and LPMOs: A brick to bridge fields of expertise. Biotechnol Adv 2024; 72:108321. [PMID: 38336187 DOI: 10.1016/j.biotechadv.2024.108321] [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: 10/31/2023] [Revised: 02/04/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Many scientific fields, although driven by similar purposes and dealing with similar technologies, often appear so isolated and far from each other that even the vocabularies to describe the very same phenomenon might differ. Concerning the vast field of biocatalysis, a special role is played by those redox enzymes that employ oxygen-based chemistry to unlock transformations otherwise possible only with metal-based catalysts. As such, greener chemical synthesis methods and environmentally-driven biotechnological approaches were enabled over the last decades by the use of several enzymes and ultimately resulted in the first industrial applications. Among what can be called today the environmental biorefinery sector, biomass transformation, greenhouse gas reduction, bio-gas/fuels production, bioremediation, as well as bulk or fine chemicals and even pharmaceuticals manufacturing are all examples of fields in which successful prototypes have been demonstrated employing redox enzymes. In this review we decided to focus on the most prominent enzymes (MMOs, LPMO, P450 and UPO) capable of overcoming the ∼100 kcal mol-1 barrier of inactivated CH bonds for the oxyfunctionalization of organic compounds. Harnessing the enormous potential that lies within these enzymes is of extreme value to develop sustainable industrial schemes and it is still deeply coveted by many within the aforementioned fields of application. Hence, the ambitious scope of this account is to bridge the current cutting-edge knowledge gathered upon each enzyme. By creating a broad comparison, scientists belonging to the different fields may find inspiration and might overcome obstacles already solved by the others. This work is organised in three major parts: a first section will be serving as an introduction to each one of the enzymes regarding their structural and activity diversity, whereas a second one will be encompassing the mechanistic aspects of their catalysis. In this regard, the machineries that lead to analogous catalytic outcomes are depicted, highlighting the major differences and similarities. Finally, a third section will be focusing on the elements that allow the oxyfunctionalization chemistry to occur by delivering redox equivalents to the enzyme by the action of diverse redox partners. Redox partners are often overlooked in comparison to the catalytic counterparts, yet they represent fundamental elements to better understand and further develop practical applications based on mono- and peroxygenases.
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Affiliation(s)
- Davide Decembrino
- Photobiocatalysis Unit - Crop Production and Biostimulation Lab (CPBL), and Biomass Transformation Lab (BTL), École Interfacultaire de Bioingénieurs, Université Libre de Bruxelles, Belgium.
| | - David Cannella
- Photobiocatalysis Unit - Crop Production and Biostimulation Lab (CPBL), and Biomass Transformation Lab (BTL), École Interfacultaire de Bioingénieurs, Université Libre de Bruxelles, Belgium.
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7
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Su Y, Liu W, Rahaman MH, Chen Z, Zhai J. Methane emission from water level fluctuation zone of the Three Gorges Reservoir: Seasonal variation and microbial mechanism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168935. [PMID: 38042199 DOI: 10.1016/j.scitotenv.2023.168935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 11/22/2023] [Accepted: 11/25/2023] [Indexed: 12/04/2023]
Abstract
Periodic and significant water level fluctuations within the Three Gorges Reservoir (TGR) create a complex water level fluctuation zone (WLFZ) that can significantly influence greenhouse gas emissions. However, the scarcity of comprehensive studies investigating long-term monitoring and analysis of CH4 flux patterns and underlying mechanisms concerning water level variations, environmental characteristics, and microbial communities has limited our understanding. This study conducted a four-year monitoring campaign to examine in situ CH4 emissions from three representative sampling sites. Results indicated that the CH4 flux remained relatively stable at lower water levels, specifically at the control site (S1). However, water level fluctuations significantly influenced CH4 emissions at the sampling sites situated within the WLFZ. Notably, the highest CH4 flux of 0.252 ± 0.089 mg/(m2·h) was observed during the drying period (June to August), while the lowest CH4 flux of 0.048 ± 0.026 mg/(m2·h) was recorded during the flooding period. Moreover, CH4 emissions through the water-air interface surpassed those through the soil-air interface. The CH4 flux positively correlated with organic carbon, temperature, and soil moisture. The relative abundance of methane metabolism microorganisms peaked during the drying period and decreased during the impounding and flooding periods. The primary methanogenesis pathway was hydrogenotrophic, whereas methanotrophic processes were mainly aerobic, with Ca. Methylomirabilis governing the anaerobic methanotrophic process. Overall, the current findings serve as crucial theoretical references for understanding CH4 emissions and carbon metabolism processes within WLFZ environments.
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Affiliation(s)
- Yiming Su
- Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Chongqing University, Chongqing 400045, China
| | - Wenbo Liu
- Institute for Smart City of Chongqing University in Liyang, Chongqing University, Jiangsu 213300, China
| | - Md Hasibur Rahaman
- Institute for Smart City of Chongqing University in Liyang, Chongqing University, Jiangsu 213300, China
| | - Zhongbing Chen
- Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500 Praha, Suchdol, Czech Republic
| | - Jun Zhai
- Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Chongqing University, Chongqing 400045, China; Institute for Smart City of Chongqing University in Liyang, Chongqing University, Jiangsu 213300, China.
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8
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Kang NK, Chau THT, Lee EY. Engineered methane biocatalysis: strategies to assimilate methane for chemical production. Curr Opin Biotechnol 2024; 85:103031. [PMID: 38101295 DOI: 10.1016/j.copbio.2023.103031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 11/17/2023] [Accepted: 11/21/2023] [Indexed: 12/17/2023]
Abstract
Methane (CH4), one of the greenhouse gases, is considered a promising feedstock for the biological production of fuels and chemicals. Although recent studies have demonstrated the capability of methanotrophs to convert CH4 into various bioproducts by metabolic engineering, the productivity has not reached commercial levels. As such, there is a growing interest in synthetic methanotrophic systems as an alternative. This review summarizes the strategies for enhancing native CH4 assimilation and discusses the challenges for the construction of synthetic methanotrophy into nonmethanotrophic industrial strains. Additionally, we suggest a mixed heterotrophic approach that integrates CH4 assimilation with glucose and xylose metabolism to improve productivity. The synthetic methanotrophic system presented in this review could pave the way for sustainable and efficient biomanufacturing using CH4.
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Affiliation(s)
- Nam Kyu Kang
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 17104 Yongin-si, Gyeonggi-do, South Korea
| | - Tin Hoang Trung Chau
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 17104 Yongin-si, Gyeonggi-do, South Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 17104 Yongin-si, Gyeonggi-do, South Korea.
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Yu L, Jia R, Liu S, Li S, Zhong S, Liu G, Zeng RJ, Rensing C, Zhou S. Ferrihydrite-mediated methanotrophic nitrogen fixation in paddy soil under hypoxia. ISME COMMUNICATIONS 2024; 4:ycae030. [PMID: 38524761 PMCID: PMC10960957 DOI: 10.1093/ismeco/ycae030] [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: 01/11/2024] [Revised: 02/21/2024] [Accepted: 02/29/2024] [Indexed: 03/26/2024]
Abstract
Biological nitrogen fixation (BNF) by methanotrophic bacteria has been shown to play an important role in maintaining fertility. However, this process is still limited to aerobic methane oxidation with sufficient oxygen. It has remained unknown whether and how methanotrophic BNF proceeds in hypoxic environments. Herein, we incubated paddy soils with a ferrihydrite-containing mineral salt medium to enrich methanotrophic bacteria in the presence of methane (20%, v/v) under oxygen constraints (0.27%, v/v). The resulting microcosms showed that ferrihydrite-dependent aerobic methane oxidation significantly contributed (81%) to total BNF, increasing the 15N fixation rate by 13-fold from 0.02 to 0.28 μmol 15N2 (g dry weight soil) -1 d-1. BNF was reduced by 97% when ferrihydrite was omitted, demonstrating the involvement of ferrihydrite in methanotrophic BNF. DNA stable-isotope probing indicated that Methylocystis, Methylophilaceae, and Methylomicrobium were the dominant methanotrophs/methylotrophs that assimilated labeled isotopes (13C or 15N) into biomass. Metagenomic binning combined with electrochemical analysis suggested that Methylocystis and Methylophilaceae had the potential to perform methane-induced BNF and likely utilized riboflavin and c-type cytochromes as electron carriers for ferrihydrite reduction. It was concluded that ferrihydrite mediated methanotrophic BNF by methanotrophs/methylotrophs solely or in conjunction with iron-reducing bacteria. Overall, this study revealed a previously overlooked yet pronounced coupling of iron-dependent aerobic methane oxidation to BNF and improves our understanding of methanotrophic BNF in hypoxic zones.
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Affiliation(s)
- Linpeng Yu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Rong Jia
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of Land Resources Evaluation and Monitoring in Southwest China, Ministry of Education, Sichuan Normal University, Chengdu, Sichuan Province 610066, China
| | - Shiqi Liu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shuan Li
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Sining Zhong
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Guohong Liu
- Agricultural Bio-resources Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350003, China
| | - Raymond Jianxiong Zeng
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Christopher Rensing
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shungui Zhou
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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Fenibo EO, Selvarajan R, Wang H, Wang Y, Abia ALK. Untapped talents: insight into the ecological significance of methanotrophs and its prospects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166145. [PMID: 37579801 DOI: 10.1016/j.scitotenv.2023.166145] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/06/2023] [Accepted: 08/06/2023] [Indexed: 08/16/2023]
Abstract
The deep ocean is a rich reservoir of unique organisms with great potential for bioprospecting, ecosystem services, and the discovery of novel materials. These organisms thrive in harsh environments characterized by high hydrostatic pressure, low temperature, and limited nutrients. Hydrothermal vents and cold seeps, prominent features of the deep ocean, provide a habitat for microorganisms involved in the production and filtration of methane, a potent greenhouse gas. Methanotrophs, comprising archaea and bacteria, play a crucial role in these processes. This review examines the intricate relationship between the roles, responses, and niche specialization of methanotrophs in the deep ocean ecosystem. Our findings reveal that different types of methanotrophs dominate specific zones depending on prevailing conditions. Type I methanotrophs thrive in oxygen-rich zones, while Type II methanotrophs display adaptability to diverse conditions. Verrumicrobiota and NC10 flourish in hypoxic and extreme environments. In addition to their essential role in methane regulation, methanotrophs contribute to various ecosystem functions. They participate in the degradation of foreign compounds and play a crucial role in cycling biogeochemical elements like metals, sulfur, and nitrogen. Methanotrophs also serve as a significant energy source for the oceanic food chain and drive chemosynthesis in the deep ocean. Moreover, their presence offers promising prospects for biotechnological applications, including the production of valuable compounds such as polyhydroxyalkanoates, methanobactin, exopolysaccharides, ecotines, methanol, putrescine, and biofuels. In conclusion, this review highlights the multifaceted roles of methanotrophs in the deep ocean ecosystem, underscoring their ecological significance and their potential for advancements in biotechnology. A comprehensive understanding of their niche specialization and responses will contribute to harnessing their full potential in various domains.
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Affiliation(s)
- Emmanuel Oliver Fenibo
- World Bank Africa Centre of Excellence, Centre for Oilfield Chemical Research, University of Port Harcourt, Port Harcourt 500272, Nigeria
| | - Ramganesh Selvarajan
- Laboratory of Extraterrestrial Ocean Systems (LEOS), Institute of Deep-Sea Science and Engineering (IDSSE), Chinese Academy of Sciences (CAS), Sanya, China; Department of Environmental Science, University of South Africa, Florida Campus, 1710, South Africa
| | - Huiqi Wang
- Laboratory of Extraterrestrial Ocean Systems (LEOS), Institute of Deep-Sea Science and Engineering (IDSSE), Chinese Academy of Sciences (CAS), Sanya, China
| | - Yue Wang
- Laboratory of Extraterrestrial Ocean Systems (LEOS), Institute of Deep-Sea Science and Engineering (IDSSE), Chinese Academy of Sciences (CAS), Sanya, China
| | - Akebe Luther King Abia
- Environmental Research Foundation, Westville 3630, South Africa; Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa.
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11
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Woern C, Grossmann L. Microbial gas fermentation technology for sustainable food protein production. Biotechnol Adv 2023; 69:108240. [PMID: 37647973 DOI: 10.1016/j.biotechadv.2023.108240] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 08/16/2023] [Accepted: 08/21/2023] [Indexed: 09/01/2023]
Abstract
The development of novel, sustainable, and robust food production technologies represents one of the major pillars to address the most significant challenges humanity is going to face on earth in the upcoming decades - climate change, population growth, and resource depletion. The implementation of microfoods, i.e., foods formulated with ingredients from microbial cultivation, into the food supply chain has a huge potential to contribute towards energy-efficient and nutritious food manufacturing and represents a means to sustainably feed a growing world population. This review recapitulates and assesses the current state in the establishment and usage of gas fermenting bacteria as an innovative feedstock for protein production. In particular, we focus on the most promising representatives of this taxon: the hydrogen-oxidizing bacteria (hydrogenotrophs) and the methane-oxidizing bacteria (methanotrophs). These unicellular microorganisms can aerobically metabolize gaseous hydrogen and methane, respectively, to provide the required energy for building up cell material. A protein yield over 70% in the dry matter cell mass can be reached with no need for arable land and organic substrates making it a promising alternative to plant- and animal-based protein sources. We illuminate the holistic approach to incorporate protein extracts obtained from the cultivation of gas fermenting bacteria into microfoods. Herein, the fundamental properties of the bacteria, cultivation methods, downstream processing, and potential food applications are discussed. Moreover, this review covers existing and future challenges as well as sustainability aspects associated with the production of microbial protein through gas fermentation.
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Affiliation(s)
- Carlos Woern
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA
| | - Lutz Grossmann
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA.
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12
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Poma N, Bonini A, Vivaldi F, Biagini D, Di Luca M, Bottai D, Di Francesco F, Tavanti A. Biosensing systems for the detection and quantification of methane gas. Appl Microbiol Biotechnol 2023; 107:5627-5634. [PMID: 37486352 PMCID: PMC10439851 DOI: 10.1007/s00253-023-12629-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 06/03/2023] [Accepted: 06/07/2023] [Indexed: 07/25/2023]
Abstract
Climate change due to the continuous increase in the release of green-house gasses associated with anthropogenic activity has made a significant impact on the sustainability of life on our planet. Methane (CH4) is a green-house gas whose concentrations in the atmosphere are on the rise. CH4 measurement is important for both the environment and the safety at the industrial and household level. Methanotrophs are distinguished for their unique characteristic of using CH4 as the sole source of carbon and energy, due to the presence of the methane monooxygenases that oxidize CH4 under ambient temperature conditions. This has attracted interest in the use of methanotrophs in biotechnological applications as well as in the development of biosensing systems for CH4 quantification and monitoring. Biosensing systems using methanotrophs rely on the use of whole microbial cells that oxidize CH4 in presence of O2, so that the CH4 concentration is determined in an indirect manner by measuring the decrease of O2 level in the system. Although several biological properties of methanotrophic microorganisms still need to be characterized, different studies have demonstrated the feasibility of the use of methanotrophs in CH4 measurement. This review summarizes the contributions in methane biosensing systems and presents a prospective of the valid use of methanotrophs in this field. KEY POINTS: • Methanotroph environmental relevance in methane oxidation • Methanotroph biotechnological application in the field of biosensing • Methane monooxygenase as a feasible biorecognition element in biosensors.
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Affiliation(s)
- Noemi Poma
- Department of Biology, University of Pisa, Via San Zeno 35-39, 56127, Pisa, Italy
| | - Andrea Bonini
- Department of Biology, University of Pisa, Via San Zeno 35-39, 56127, Pisa, Italy
- Groningen Biomolecular Sciences and Biotechnology, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Federico Vivaldi
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
- Metitech S.R.L., Via Livornese 835, 56122, Pisa, Italy
| | - Denise Biagini
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
| | - Mariagrazia Di Luca
- Department of Biology, University of Pisa, Via San Zeno 35-39, 56127, Pisa, Italy
| | - Daria Bottai
- Department of Biology, University of Pisa, Via San Zeno 35-39, 56127, Pisa, Italy
| | - Fabio Di Francesco
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via Giuseppe Moruzzi 13, 56124, Pisa, Italy
- Metitech S.R.L., Via Livornese 835, 56122, Pisa, Italy
| | - Arianna Tavanti
- Department of Biology, University of Pisa, Via San Zeno 35-39, 56127, Pisa, Italy.
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13
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Hwangbo M, Shao Y, Hatzinger PB, Chu KH. Acidophilic methanotrophs: Occurrence, diversity, and possible bioremediation applications. ENVIRONMENTAL MICROBIOLOGY REPORTS 2023. [PMID: 37041665 DOI: 10.1111/1758-2229.13156] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 06/19/2023]
Abstract
Methanotrophs have been identified and isolated from acidic environments such as wetlands, acidic soils, peat bogs, and groundwater aquifers. Due to their methane (CH4 ) utilization as a carbon and energy source, acidophilic methanotrophs are important in controlling the release of atmospheric CH4 , an important greenhouse gas, from acidic wetlands and other environments. Methanotrophs have also played an important role in the biodegradation and bioremediation of a variety of pollutants including chlorinated volatile organic compounds (CVOCs) using CH4 monooxygenases via a process known as cometabolism. Under neutral pH conditions, anaerobic bioremediation via carbon source addition is a commonly used and highly effective approach to treat CVOCs in groundwater. However, complete dechlorination of CVOCs is typically inhibited at low pH. Acidophilic methanotrophs have recently been observed to degrade a range of CVOCs at pH < 5.5, suggesting that cometabolic treatment may be an option for CVOCs and other contaminants in acidic aquifers. This paper provides an overview of the occurrence, diversity, and physiological activities of methanotrophs in acidic environments and highlights the potential application of these organisms for enhancing contaminant biodegradation and bioremediation.
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Affiliation(s)
- Myung Hwangbo
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, Texas, USA
| | - Yiru Shao
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, Texas, USA
| | - Paul B Hatzinger
- Aptim Federal Services, LLC, 17 Princess Road, Lawrenceville, New Jersey, USA
| | - Kung-Hui Chu
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, Texas, USA
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14
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Yu Z, Peng X, Liu L, Yang JR, Zhai X, Xue Y, Mo Y, Yang J. Microbial one‑carbon and nitrogen metabolisms are beneficial to the reservoir recovery after cyanobacterial bloom. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159004. [PMID: 36155037 DOI: 10.1016/j.scitotenv.2022.159004] [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: 07/06/2022] [Revised: 09/03/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Cyanobacterial blooms have profound effects on the structure and function of plankton communities in inland waters, but few studies have focused on the effects of microbial-based processes in one‑carbon and nitrogen cycling on water quality improvement following the bloom. Here, we compared the structure and function of the bacterial community, focusing on microbial one‑carbon and nitrogen metabolisms during and after a cyanobacterial Microcystis bloom in a deep subtropical reservoir. Our data showed that microbial one‑carbon and nitrogen cycles were closely related to different periods of the bloom, and the changes of functional genes in microbial carbon and nitrogen cycling showed the same consistent trend as that of Methylomonas sp. With the receding of the bloom, the abundance of Methylomonas as well as the functional genes of microbial one‑carbon and nitrogen cycling reached the peak and then recovered. Our results indicate that microbial one‑carbon and nitrogen metabolisms were beneficial to the recovery of water quality from the cyanobacterial bloom. This study lays a foundation for a deep understanding of the cyanobacterial decomposition mediated by microbes in one‑carbon and nitrogen cycles in inland freshwaters.
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Affiliation(s)
- Zheng Yu
- Department of Microbiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410083, China; Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xuan Peng
- Department of Microbiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410083, China
| | - Lemian Liu
- College of Biological Science and Engineering, Fuzhou University, Fuzhou 350108, China
| | - Jun R Yang
- Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xingyu Zhai
- Department of Microbiology, Xiangya School of Medicine, Central South University, Changsha, Hunan 410083, China
| | - Yuanyuan Xue
- Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yuanyuan Mo
- Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Jun Yang
- Aquatic EcoHealth Group, Fujian Key Laboratory of Watershed Ecology, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
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15
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Le HTQ, Lee EY. Insights into C1 and C3 assimilation pathways in type I methanotrophic bacterium from co-production of 1,2-propanediol and lactate. BIORESOURCE TECHNOLOGY 2022; 365:128172. [PMID: 36279980 DOI: 10.1016/j.biortech.2022.128172] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/15/2022] [Accepted: 10/17/2022] [Indexed: 06/16/2023]
Abstract
Methanotrophic bacteria are attractive hosts for mining metabolic pathways of C1 assimilation to produce value-added products. Herein, the type I methanotroph Methylotuvimicrobium alcaliphilum 20Z was employed to explore the carbon flux from methane and methanol via the EMP pathway to produce 1,2-propanediol (1,2-PDO). The production of 1,2-PDO on methane was found to be mainly restricted by the lower carbon flux toward the EMP pathway. The co-utilization of C1 substrates and glycerol (C3) could contribute to enhance 1,2-PDO. Lactate was co-produced in much higher amounts than 1,2-PDO. This unexpected product was probably derived from lactaldehyde by inherent aldehyde dehydrogenases. The 1,2-PDO production without increased accumulation of lactate was observed via establishing the acetol-based pathway by propane utilization with the overexpression of pmoD. This is the first study to provide experimental insights into the operation of metabolic routes for 1,2-PDO and lactate co-production from C1 and C3 compounds in methanotrophs.
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Affiliation(s)
- Hoa Thi Quynh Le
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin 17104, Republic of Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin 17104, Republic of Korea.
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Khmelenina VN, But SY, Rozova ON, Oshkin IY, Pimenov NV, Dedysh SN. Genome Editing in Methanotrophic Bacteria: Potential Targets and Available Tools. Microbiology (Reading) 2022. [DOI: 10.1134/s0026261722602196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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17
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Khanongnuch R, Mangayil R, Santala V, Hestnes AG, Svenning MM, Rissanen AJ. Batch Experiments Demonstrating a Two-Stage Bacterial Process Coupling Methanotrophic and Heterotrophic Bacteria for 1-Alkene Production From Methane. Front Microbiol 2022; 13:874627. [PMID: 35663866 PMCID: PMC9162803 DOI: 10.3389/fmicb.2022.874627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 04/22/2022] [Indexed: 11/13/2022] Open
Abstract
Methane (CH4) is a sustainable carbon feedstock for value-added chemical production in aerobic CH4-oxidizing bacteria (methanotrophs). Under substrate-limited (e.g., oxygen and nitrogen) conditions, CH4 oxidation results in the production of various short-chain organic acids and platform chemicals. These CH4-derived products could be broadened by utilizing them as feedstocks for heterotrophic bacteria. As a proof of concept, a two-stage system for CH4 abatement and 1-alkene production was developed in this study. Type I and Type II methanotrophs, Methylobacter tundripaludum SV96 and Methylocystis rosea SV97, respectively, were investigated in batch tests under different CH4 and air supplementation schemes. CH4 oxidation under either microaerobic or aerobic conditions induced the production of formate, acetate, succinate, and malate in M. tundripaludum SV96, accounting for 4.8–7.0% of consumed carbon from CH4 (C-CH4), while M. rosea SV97 produced the same compounds except for malate, and with lower efficiency than M. tundripaludum SV96, accounting for 0.7–1.8% of consumed C-CH4. For the first time, this study demonstrated the use of organic acid-rich spent media of methanotrophs cultivating engineered Acinetobacter baylyi ADP1 ‘tesA-undA cells for 1-alkene production. The highest yield of 1-undecene was obtained from the spent medium of M. tundripaludum SV96 at 68.9 ± 11.6 μmol mol Csubstrate–1. However, further large-scale studies on fermenters and their optimization are required to increase the production yields of organic acids in methanotrophs.
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Affiliation(s)
- Ramita Khanongnuch
- Materials Science and Environmental Engineering, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
| | - Rahul Mangayil
- Materials Science and Environmental Engineering, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
| | - Ville Santala
- Materials Science and Environmental Engineering, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
| | - Anne Grethe Hestnes
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Mette Marianne Svenning
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Antti J Rissanen
- Materials Science and Environmental Engineering, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
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18
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Enhancement of Methane Catalysis Rates in Methylosinus trichosporium OB3b. Biomolecules 2022; 12:biom12040560. [PMID: 35454149 PMCID: PMC9024549 DOI: 10.3390/biom12040560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 02/05/2023] Open
Abstract
Particulate methane monooxygenase (pMMO), a membrane-bound enzyme having three subunits (α, β, and γ) and copper-containing centers, is found in most of the methanotrophs that selectively catalyze the oxidation of methane into methanol. Active sites in the pMMO of Methylosinus trichosporium OB3b were determined by docking the modeled structure with ethylbenzene, toluene, 1,3-dibutadiene, and trichloroethylene. The docking energy between the modeled pMMO structure and ethylbenzene, toluene, 1,3-dibutadiene, and trichloroethylene was −5.2, −5.7, −4.2, and −3.8 kcal/mol, respectively, suggesting the existence of more than one active site within the monomeric subunits due to the presence of multiple binding sites within the pMMO monomer. The evaluation of tunnels and cavities of the active sites and the docking results showed that each active site is specific to the radius of the substrate. To increase the catalysis rates of methane in the pMMO of M. trichosporium OB3b, selected amino acid residues interacting at the binding site of ethylbenzene, toluene, 1,3-dibutadiene, and trichloroethylene were mutated. Based on screening the strain energy, docking energy, and physiochemical properties, five mutants were downselected, B:Leu31Ser, B:Phe96Gly, B:Phe92Thr, B:Trp106Ala, and B:Tyr110Phe, which showed the docking energy of −6.3, −6.7, −6.3, −6.5, and −6.5 kcal/mol, respectively, as compared to the wild type (−5.2 kcal/mol) with ethylbenzene. These results suggest that these five mutants would likely increase methane oxidation rates compared to wild-type pMMO.
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Gonzaga de França Lopes L, Gouveia Júnior FS, Karine Medeiros Holanda A, Maria Moreira de Carvalho I, Longhinotti E, Paulo TF, Abreu DS, Bernhardt PV, Gilles-Gonzalez MA, Cirino Nogueira Diógenes I, Henrique Silva Sousa E. Bioinorganic systems responsive to the diatomic gases O2, NO, and CO: From biological sensors to therapy. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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