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Gao R, Pan H, Kai L, Han K, Lian J. Microbial degradation and valorization of poly(ethylene terephthalate) (PET) monomers. World J Microbiol Biotechnol 2022; 38:89. [PMID: 35426614 DOI: 10.1007/s11274-022-03270-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/23/2022] [Indexed: 12/22/2022]
Abstract
The polyethylene terephthalate (PET) is one of the major plastics with a huge annual production. Alongside with its mass production and wide applications, PET pollution is threatening and damaging the environment and human health. Although mechanical or chemical methods can deal with PET, the process suffers from high cost and the hydrolyzed monomers will cause secondary pollution. Discovery of plastic-degrading microbes and the corresponding enzymes emerges new hope to cope with this issue. Combined with synthetic biology and metabolic engineering, microbial cell factories not only provide a promising approach to degrade PET, but also enable the conversion of its monomers, ethylene glycol (EG) and terephthalic acid (TPA), into value-added compounds. In this way, PET wastes can be handled in environment-friendly and more potentially cost-effective processes. While PET hydrolases have been extensively reviewed, this review focuses on the microbes and metabolic pathways for the degradation of PET monomers. In addition, recent advances in the biotransformation of TPA and EG into value-added compounds are discussed in detail.
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Affiliation(s)
- Rui Gao
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, 310027, Hangzhou, China.,Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, 310027, Hangzhou, China
| | - Haojie Pan
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, 310027, Hangzhou, China
| | - Lei Kai
- Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life Sciences, Jiangsu Normal University, 22116, Xuzhou, China.,Jiangsu Keybio Co. LTD, 22116, Xuzhou, China
| | - Kun Han
- Jiangsu Keybio Co. LTD, 22116, Xuzhou, China
| | - Jiazhang Lian
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, 310027, Hangzhou, China. .,Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, 310027, Hangzhou, China.
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Gautam J, Xu H, Hu J, Pennacchio C, Lipzen A, Martin J, Xu Z. Adapted laboratory evolution of Thermotoga sp. strain RQ7 under carbon starvation. BMC Res Notes 2022; 15:99. [PMID: 35272671 PMCID: PMC8908640 DOI: 10.1186/s13104-022-05982-9] [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: 09/27/2021] [Accepted: 02/22/2022] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Adaptive laboratory evolution (ALE) is an effective approach to study the evolution behavior of bacterial cultures and to select for strains with desired metabolic features. In this study, we explored the possibility of evolving Thermotoga sp. strain RQ7 for cellulose-degrading abilities. RESULTS Wild type RQ7 strain was subject to a series of transfers over six and half years with cellulose filter paper as the main and eventually the sole carbon source. Each transfer was accompanied with the addition of 50 μg of Caldicellulosiruptor saccharolyticus DSM 8903 genomic DNA. A total of 331 transfers were completed. No cellulose degradation was observed with the RQ7 cultures. Thirty three (33) isolates from six time points were sampled and sequenced. Nineteen (19) of the 33 isolates were unique, and the rest were duplicated clones. None of the isolates acquired C. saccharolyticus DNA, but all accumulated small-scale mutations throughout their genomes. Sequence analyses revealed 35 mutations that were preserved throughout the generations and another 15 mutations emerged near the end of the study. Many of the affected genes participate in phosphate metabolism, substrate transport, stress response, sensory transduction, and gene regulation.
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Affiliation(s)
- Jyotshana Gautam
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA
| | - Hui Xu
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA
| | - Junxi Hu
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA.,School of Life Sciences, Minnan Normal University, 36 Xianqianzhi Street, Zhangzhou, 363000, Fujian, China
| | - Christa Pennacchio
- Department of Energy-Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Anna Lipzen
- Department of Energy-Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Joel Martin
- Department of Energy-Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Zhaohui Xu
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA.
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An Escherichia coli FdrA Variant Derived from Syntrophic Coculture with a Methanogen Increases Succinate Production Due to Changes in Allantoin Degradation. mSphere 2021; 6:e0065421. [PMID: 34494882 PMCID: PMC8550087 DOI: 10.1128/msphere.00654-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Wild-type Escherichia coli was adapted to syntrophic growth with Methanobacterium formicicum for glycerol fermentation over 44 weeks. Succinate production by E. coli started to increase in the early stages of syntrophic growth. Genetic analysis of the cultured E. coli population by pooled sequencing at eight time points suggests that (i) rapid evolution occurred through repeated emergence of mutators that introduced a large number of nucleotide variants and (ii) many mutators increased to high frequencies but remained polymorphic throughout the continuous cultivation. The evolved E. coli populations exhibited gains both in fitness and succinate production, but only for growth under glycerol fermentation with M. formicicum (the condition for this laboratory evolution) and not under other growth conditions. The mutant alleles of the 69 single nucleotide polymorphisms (SNPs) identified in the adapted E. coli populations were constructed individually in the ancestral wild-type E. coli. We analyzed the phenotypic changes caused by 84 variants, including 15 nonsense variants, and found that FdrAD296Y was the most significant variant leading to increased succinate production. Transcription of fdrA was induced under anaerobic allantoin degradation conditions, and FdrA was shown to play a crucial role in oxamate production. The FdrAD296Y variant increased glyoxylate conversion to malate by accelerating oxamate production, which promotes carbon flow through the C4 branch, leading to increased succinate production. IMPORTANCE Here, we demonstrate the ability of E. coli to perform glycerol fermentation in coculture with the methanogen M. formicicum to produce succinate. We found that the production of succinate by E. coli significantly increased during successive cocultivation. Genomic DNA sequencing, evaluation of relative fitness, and construction of SNPs were performed, from which FdrAD296Y was identified as the most significant variant to enable increased succinate production by E. coli. The function of FdrA is uncertain. In this study, experiments with gene expression assays and metabolic analysis showed for the first time that FdrA could be the “orphan enzyme” oxamate:carbamoyltransferase in anaerobic allantoin degradation. Furthermore, we demonstrate that the anaerobic allantoin degradation pathway is linked to succinate production via the glyoxylate pathway during glycerol fermentation.
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Lv Y, Jiang Y, Lu J, Gao H, Dong W, Zhou J, Zhang W, Xin F, Jiang M. Comprehensive evaluation for the one-pot biosynthesis of butyl acetate by using microbial mono- and co-cultures. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:203. [PMID: 34656153 PMCID: PMC8520270 DOI: 10.1186/s13068-021-02053-2] [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: 08/23/2021] [Accepted: 10/03/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Butyl acetate has shown wide applications in food, cosmetics, medicine, and biofuel sectors. These short-chain fatty acid esters can be produced by either chemical or biological synthetic process with corresponding alcohols and acids. Currently, biosynthesis of short chain fatty acid esters, such as butyl butyrate, through microbial fermentation systems has been achieved; however, few studies regarding biosynthesis of butyl acetate were reported. RESULTS In this study, three proof-of-principle strategies for the one-pot butyl acetate production from glucose through microbial fermentation were designed and evaluated. (1) 7.3 g/L of butyl acetate was synthesized by butanol-producing Clostridium acetobutylicum NJ4 with the supplementation of exogenous acetic acid; (2) With the addition of butanol, 5.76 g/L of butyl acetate can be synthesized by acetate-producing Actinobacillus succinogenes130z (ΔpflA); (3) Microbial co-culture of C. acetobutylicum NJ4 and A. succinogenes130z (ΔpflA) can directly produce 2.2 g/L of butyl acetate from glucose by using microbial co-culture system with the elimination of precursors. Through the further immobilization of A. succinogenes130z (ΔpflA), butyl acetate production was improved to 2.86 g/L. CONCLUSION Different microbial mono- and co-culture systems for butyl acetate biosynthesis were successfully constructed. These strategies may be extended to the biosynthesis of a wide range of esters, especially to some longer chain ones.
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Affiliation(s)
- Yang Lv
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Yujia Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China.
| | - Jiasheng Lu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Hao Gao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, 211800, People's Republic of China
| | - Jie Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China.
- Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, 211800, People's Republic of China.
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China.
- Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, 211800, People's Republic of China.
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Puzhu South Road 30#, Nanjing, 211800, People's Republic of China
- Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, 211800, People's Republic of China
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Ozogul F, Ozcelik S, Ozogul Y, Yilmaz MT. Seafood infusion broths as novel sources to produce organic acids using selected lactic acid bacteria strains. FOOD BIOSCI 2021. [DOI: 10.1016/j.fbio.2021.101227] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Salma A, Abdallah R, Fourcade F, Amrane A, Djelal H. A New Approach to Produce Succinic Acid Through a Co-Culture System. Appl Biochem Biotechnol 2021; 193:2872-2892. [PMID: 33937964 DOI: 10.1007/s12010-021-03572-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 04/08/2021] [Indexed: 01/04/2023]
Abstract
Microorganisms can produce a wide range of bio-based chemicals that can be used in various industrial applications as molecules of interest. In the present work, an analysis of the power production by pure culture, co-culture, and sequential culture was performed. In this study, both the mono-culture and the co-culture strategies of Actinobacillus succinogenes with Saccharomyces cerevisiae as carbon sources to produce succinic acid using glucose and fructose were examined. The cultures were performed in batch mode and a great attention was paid to the co-culture system to improve the biosynthetic pathway between A. succinogenes and S. cerevisiae by combining these two strains in a single fermentation process. Under microaerobic and anaerobic conditions, the process was characterized in terms of sugars concentration, cell density, metabolites, yield (mol-C products/ mol-C sugars), the temperature conditions for productivity, and pH. The results showed that the process could consume glucose and fructose and could adapt to different concentrations of the two sugars more quickly than by a single organism and the best results were obtained in a sequential co-culture recording 0.27 mol L-1 of succinic acid concentration and a volumetric productivity of 0.3 g L-1 h-1. Under the investigated operating conditions, the combination of these two strains in a single reactor produced a significant amount of succinic acid (0.70 mol-C SA/mol-C substrates). A simultaneous and sequential co-culture strategy can be a powerful new approach in the field of bio-based chemical production.
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Affiliation(s)
- Alaa Salma
- University Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR, UMR6226, F-3500, Rennes, France
| | - Rawa Abdallah
- Centre Azm pour la Recherche en Biotechnologie et ses Applications, Rue El Mitein, LBA3B, Universite Libanaise, EDST, Tripoli, Lebanon
| | - Florence Fourcade
- University Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR, UMR6226, F-3500, Rennes, France
| | - Abdeltif Amrane
- University Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR, UMR6226, F-3500, Rennes, France
| | - Hayet Djelal
- UniLaSalle-Ecole des Métiers de l'Environnement, Avenue Robert Schuman, Campus de Ker Lann, 35 170, Rennes, France.
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Diender M, Parera Olm I, Sousa DZ. Synthetic co-cultures: novel avenues for bio-based processes. Curr Opin Biotechnol 2021; 67:72-79. [PMID: 33517194 DOI: 10.1016/j.copbio.2021.01.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/23/2020] [Accepted: 01/07/2021] [Indexed: 02/06/2023]
Abstract
In nature, microorganisms live in multi-species communities allowing microbial interactions. These interactions are lost upon establishing a pure culture, increasing the metabolic burden and limiting the metabolic potential of the isolated microbe. In the past years, synthetic microbial co-cultivation, using well-defined consortia of two or more microbes, was increasingly explored for innovative applications in biotechnology. As such, interspecies interactions take place without the complexity of an open mixed culture, minimizing undesired side reactions. Ultimately, synthetic co-cultivation allows to take well-characterized microbes 'off-the-shelf' to create ecosystems with improved process capabilities. This review highlights some of the recent developments on co-cultivation, focusing on waste-to-chemicals conversions. It also addresses fundamental knowledge on microbial interactions deriving from these studies, which is important to further develop our ability to engineer functional co-cultures for bioproduction.
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Affiliation(s)
- Martijn Diender
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Ivette Parera Olm
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Diana Z Sousa
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands.
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Magalhães CP, Ribeiro JA, Guedes AP, Arantes AL, Sousa DZ, Stams AJM, Alves MM, Cavaleiro AJ. Co-cultivation of Thermoanaerobacter strains with a methanogenic partner enhances glycerol conversion. Microb Biotechnol 2020; 13:962-973. [PMID: 32154666 PMCID: PMC7264899 DOI: 10.1111/1751-7915.13506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 10/07/2019] [Accepted: 10/13/2019] [Indexed: 11/30/2022] Open
Abstract
Glycerol-rich waste streams produced by the biodiesel, bioethanol and oleochemical industries can be treated and valorized by anaerobic microbial communities to produce methane. As current knowledge of the microorganisms involved in thermophilic glycerol conversion to methane is scarce, thermophilic glycerol-degrading methanogenic communities were enriched. A co-culture of Thermoanaerobacter and Methanothermobacter species was obtained, pointing to a non-obligately syntrophic glycerol degradation. This hypothesis was further studied by incubating Thermoanaerobacter brockii subsp. finnii and T. wiegelii with glycerol (10 mM) in pure culture and with different hydrogenotrophic methanogens. The presence of the methanogen accelerated glycerol fermentation by the two Thermoanaerobacter strains up to 3.3 mM day-1 , corresponding to 12 times higher volumetric glycerol depletion rates in the methanogenic co-cultures than in the pure bacterial cultures. The catabolic pathways of glycerol conversion were identified by genome analysis of the two Thermoanaerobacter strains. NADH and reduced ferredoxin formed in the pathway are linked to proton reduction, which becomes thermodynamically favourable when the hydrogen partial pressure is kept low by the hydrogenotrophic methanogenic partner.
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Affiliation(s)
| | - Joaquim A. Ribeiro
- Centre of Biological EngineeringUniversity of MinhoBragaPortugal
- Present address:
Optimizer ‐ Serviços e Consultadoria Informática Lda.PortoPortugal
| | - Ana P. Guedes
- Centre of Biological EngineeringUniversity of MinhoBragaPortugal
- Present address:
Agricultural Superior School of Ponte de LimaPolytechnic Institute of Viana do CasteloViana do CasteloPortugal
| | - Ana L. Arantes
- Centre of Biological EngineeringUniversity of MinhoBragaPortugal
| | - Diana Z. Sousa
- Centre of Biological EngineeringUniversity of MinhoBragaPortugal
- Laboratory of MicrobiologyWageningen University and ResearchWageningenThe Netherlands
| | - Alfons J. M. Stams
- Centre of Biological EngineeringUniversity of MinhoBragaPortugal
- Laboratory of MicrobiologyWageningen University and ResearchWageningenThe Netherlands
| | - Maria M. Alves
- Centre of Biological EngineeringUniversity of MinhoBragaPortugal
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Kim SN, Cho YB, Park JW, Kim OB. Adaptation of Methanosarcina barkeri 227 as acetate scavenger for succinate fermentation by Actinobacillus succinogenes. Appl Microbiol Biotechnol 2020; 104:4483-4492. [PMID: 32185433 DOI: 10.1007/s00253-020-10494-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 02/14/2020] [Accepted: 02/20/2020] [Indexed: 11/29/2022]
Abstract
Acetate is the main by-product from microbial succinate production. In this study, we performed acetate removal by Methanosarcina barkeri 227 for succinate fermentation by Actinobacillus succinogenes 130Z. The acetoclastic methanogen M. barkeri requires similar environmental factors to A. succinogenes, and the conditions required for co-cultivation were optimized in this study: gas used for anaerobicization, strain adaptation, medium composition, pH adjustment, and inoculation time points. M. barkeri 227 was adapted to acetate for 150 days, which accelerated the acetate consumption to 9-fold (from 190 to 1726 mmol gDW-1 day-1). In the acetate-adapted strain, there was a noticeable increase in transcription of genes required for acetoclastic pathway-satP (acetate transporter), ackA (acetate kinase), cdhA (carbon monoxide dehydrogenase/acetyl-CoA synthase complex), and mtrH (methyl-H4STP:CoM methyltransferase), which was not induced before the adaptation process. The activities of two energy-consuming steps in the pathway-acetate uptake and acetate kinase-increased about 3-fold. This acetate-adapted M. barkeri could be successfully applied to succinate fermentation culture of A. succinogenes, but only after pH adjustment following completion of fermentation. This study suggests the utility of M. barkeri as an acetate scavenger during fermentation for further steps towards genetic and process engineering.
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Affiliation(s)
- Su Nyoung Kim
- Division of EcoScience and Interdisciplinary Program of EcoCreative, Graduate School, Ewha Womans University, Seoul, 03760, South Korea
| | - Young Bin Cho
- Division of EcoScience and Interdisciplinary Program of EcoCreative, Graduate School, Ewha Womans University, Seoul, 03760, South Korea
| | - Ji Won Park
- Division of EcoScience and Interdisciplinary Program of EcoCreative, Graduate School, Ewha Womans University, Seoul, 03760, South Korea
| | - Ok Bin Kim
- Division of EcoScience and Interdisciplinary Program of EcoCreative, Graduate School, Ewha Womans University, Seoul, 03760, South Korea. .,Department of Life Science, Ewha Womans University, Seoul, 03760, South Korea.
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Formate-removing inoculum dominated by Methanobacterium congolense supports succinate production from crude glycerol fermentation. J Ind Microbiol Biotechnol 2019; 46:625-634. [PMID: 30783892 DOI: 10.1007/s10295-019-02154-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 02/12/2019] [Indexed: 10/27/2022]
Abstract
We developed a formate-removing methanogenic inoculum (FRI) to facilitate succinate production from crude glycerol by Escherichia coli. FRI converted formate to methane, thereby enabling glycerol fermentation without additional electron acceptors under neutral pH. FRI was selectively enriched from sludge from the anaerobic digester of the Seonam sewage treatment plant (Seoul); this process was assessed via Illumina sequencing and scanning electron microscopy imaging. Methanobacterium congolense species occupied only 0.3% of the archaea community in the sludge and was enriched to 99.5% in complete FRI, wherein succinate-degrading bacteria were successfully eliminated. Co-culture with FRI improved glycerol fermentation and yielded 7.3 mM succinate from 28.7 mM crude glycerol, whereby FRI completely converted formate into methane. This study is the first to demonstrate methane production by M. congolense species, using formate. M. congolense-dominated FRI can serve as a renewable facilitator of waste feedstock fermentation and enable the production of commercially important compounds.
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