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Böer T, Engelhardt L, Lüschen A, Eysell L, Yoshida H, Schneider D, Angenent LT, Basen M, Daniel R, Poehlein A. Isolation and characterization of novel acetogenic Moorella strains for employment as potential thermophilic biocatalysts. FEMS Microbiol Ecol 2024; 100:fiae109. [PMID: 39118367 PMCID: PMC11328732 DOI: 10.1093/femsec/fiae109] [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: 03/25/2024] [Revised: 06/05/2024] [Accepted: 08/07/2024] [Indexed: 08/10/2024] Open
Abstract
Thermophilic acetogenic bacteria have attracted attention as promising candidates for biotechnological applications such as syngas fermentation, microbial electrosynthesis, and methanol conversion. Here, we aimed to isolate and characterize novel thermophilic acetogens from diverse environments. Enrichment of heterotrophic and autotrophic acetogens was monitored by 16S rRNA gene-based bacterial community analysis. Seven novel Moorella strains were isolated and characterized by genomic and physiological analyses. Two Moorella humiferrea isolates showed considerable differences during autotrophic growth. The M. humiferrea LNE isolate (DSM 117358) fermented carbon monoxide (CO) to acetate, while the M. humiferrea OCP isolate (DSM 117359) transformed CO to hydrogen and carbon dioxide (H2 + CO2), employing the water-gas shift reaction. Another carboxydotrophic hydrogenogenic Moorella strain was isolated from the covering soil of an active charcoal burning pile and proposed as the type strain (ACPsT) of the novel species Moorella carbonis (DSM 116161T and CCOS 2103T). The remaining four novel strains were affiliated with Moorella thermoacetica and showed, together with the type strain DSM 2955T, the production of small amounts of ethanol from H2 + CO2 in addition to acetate. The physiological analyses of the novel Moorella strains revealed isolate-specific differences that considerably increase the knowledge base on thermophilic acetogens for future applications.
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Affiliation(s)
- Tim Böer
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Lisa Engelhardt
- Microbiology, Institute of Biological Sciences, University Rostock, 18059 Rostock, Germany
| | - Alina Lüschen
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Lena Eysell
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Hiroki Yoshida
- Environmental Biotechnology Group, Department of Geosciences, University of Tübingen, 72074 Tübingen, Germany
| | - Dominik Schneider
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Largus T Angenent
- Environmental Biotechnology Group, Department of Geosciences, University of Tübingen, 72074 Tübingen, Germany
| | - Mirko Basen
- Microbiology, Institute of Biological Sciences, University Rostock, 18059 Rostock, Germany
| | - Rolf Daniel
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Anja Poehlein
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, 37077 Göttingen, Germany
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Moon J, Poehlein A, Daniel R, Müller V. Redirecting electron flow in Acetobacterium woodii enables growth on CO and improves growth on formate. Nat Commun 2024; 15:5424. [PMID: 38926344 PMCID: PMC11208171 DOI: 10.1038/s41467-024-49680-5] [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: 01/04/2024] [Accepted: 06/14/2024] [Indexed: 06/28/2024] Open
Abstract
Anaerobic, acetogenic bacteria are well known for their ability to convert various one-carbon compounds, promising feedstocks for a future, sustainable biotechnology, to products such as acetate and biofuels. The model acetogen Acetobacterium woodii can grow on CO2, formate or methanol, but not on carbon monoxide, an important industrial waste product. Since hydrogenases are targets of CO inhibition, here, we genetically delete the two [FeFe] hydrogenases HydA2 and HydBA in A. woodii. We show that the ∆hydBA/hydA2 mutant indeed grows on CO and produces acetate, but only after a long adaptation period. SNP analyzes of CO-adapted cells reveal a mutation in the HycB2 subunit of the HydA2/HydB2/HydB3/Fdh-containing hydrogen-dependent CO2 reductase (HDCR). We observe an increase in ferredoxin-dependent CO2 reduction and vice versa by the HDCR in the absence of the HydA2 module and speculate that this is caused by the mutation in HycB2. In addition, the CO-adapted ∆hydBA/hydA2 mutant growing on formate has a final biomass twice of that of the wild type.
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Affiliation(s)
- Jimyung Moon
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, Germany
| | - Anja Poehlein
- Göttingen Genomics Laboratory, Institute for Microbiology and Genetics, Georg August University, Grisebachstr. 8, Göttingen, Germany
| | - Rolf Daniel
- Göttingen Genomics Laboratory, Institute for Microbiology and Genetics, Georg August University, Grisebachstr. 8, Göttingen, Germany
| | - Volker Müller
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, Germany.
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Yao H, Rinta-Kanto JM, Vassilev I, Kokko M. Methanol as a co-substrate with CO 2 enhances butyrate production in microbial electrosynthesis. Appl Microbiol Biotechnol 2024; 108:372. [PMID: 38874789 PMCID: PMC11178620 DOI: 10.1007/s00253-024-13218-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 05/28/2024] [Accepted: 06/02/2024] [Indexed: 06/15/2024]
Abstract
Methanol is a promising feedstock for the bio-based economy as it can be derived from organic waste streams or produced electrochemically from CO2. Acetate production from CO2 in microbial electrosynthesis (MES) has been widely studied, while more valuable compounds such as butyrate are currently attracting attention. In this study, methanol was used as a co-substrate with CO2 to enhance butyrate production in MES. Feeding with CO2 and methanol resulted in the highest butyrate production rates and titres of 0.36 ± 0.01 g L-1 d-1 and 8.6 ± 0.2 g L-1, respectively, outperforming reactors with only CO2 feeding (0.20 ± 0.03 g L-1 d-1 and 5.2 ± 0.1 g L-1, respectively). Methanol acted as electron donor and as carbon source, both of which contributed ca. 50% of the carbon in the products. Eubacterium was the dominant genus with 52.6 ± 2.5% relative abundance. Thus, we demonstrate attractive route for the use of the C1 substrates, CO2 and methanol, to produce mainly butyrate. KEY POINTS: • Butyrate was the main product from methanol and CO2 in MES • Methanol acted as both carbon and electron source in MES • Eubacterium dominating microbial culture was enriched in MES.
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Affiliation(s)
- Hui Yao
- Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - Johanna M Rinta-Kanto
- Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - Igor Vassilev
- Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - Marika Kokko
- Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland.
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4
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Xie JY, Ju J, Zhou P, Chen H, Wang SC, Wang K, Wang T, Chen XZ, Chen YC, Wang K. The mechanisms, regulations, and functions of histone lysine crotonylation. Cell Death Discov 2024; 10:66. [PMID: 38331935 PMCID: PMC10853258 DOI: 10.1038/s41420-024-01830-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 01/17/2024] [Accepted: 01/23/2024] [Indexed: 02/10/2024] Open
Abstract
Histone lysine crotonylation (Kcr) is a new acylation modification first discovered in 2011, which has important biological significance for gene expression, cell development, and disease treatment. In the past over ten years, numerous signs of progress have been made in the research on the biochemistry of Kcr modification, especially a series of Kcr modification-related "reader", "eraser", and "writer" enzyme systems are identified. The physiological function of crotonylation and its correlation with development, heredity, and spermatogenesis have been paid more and more attention. However, the development of disease is usually associated with abnormal Kcr modification. In this review, we summarized the identification of crotonylation modification, Kcr-related enzyme system, biological functions, and diseases caused by abnormal Kcr. This knowledge supplies a theoretical basis for further exploring the function of crotonylation in the future.
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Affiliation(s)
- Jing-Yi Xie
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
| | - Jie Ju
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China.
- Department of Physiology, School of Basic Medical Sciences, Shandong Second Medical University, Weifang, 261053, China.
| | - Ping Zhou
- State Key Laboratory of Cardiovascular Disease, Heart Failure center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100037, China
| | - Hao Chen
- Department of Physiology, School of Basic Medical Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Shao-Cong Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
| | - Kai Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
| | - Tao Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
| | - Xin-Zhe Chen
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
| | - Yan-Chun Chen
- Neurologic Disorders and Regenerative Repair Laboratory, Shandong Second Medical University, Weifang, 261053, China.
| | - Kun Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China.
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Ji P, Zhang G, Guo Y, Song H, Yuan X, Hu X, Guo Z, Xia P, Shen R, Wang D. Protein crotonylation: An emerging regulator in DNA damage response. Life Sci 2023; 331:122059. [PMID: 37652154 DOI: 10.1016/j.lfs.2023.122059] [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: 07/24/2023] [Revised: 08/16/2023] [Accepted: 08/28/2023] [Indexed: 09/02/2023]
Abstract
DNA damage caused by internal or external factors lead to increased genomic instability and various diseases. The DNA damage response (DDR) is a crucial mechanism that maintaining genomic stability through detecting and repairing DNA damage timely. Post-translational modifications (PTMs) play significant roles in regulation of DDR. Among the present PTMs, crotonylation has emerged as a novel identified modification that is involved in a wide range of biological processes including gene expression, spermatogenesis, cell cycle, and the development of diverse diseases. In the past decade, numerous crotonylation sites have been identified in histone and non-histone proteins, leading to a more comprehensive and deep understanding of the function and mechanisms in protein crotonylation. This review provides a comprehensive overview of the regulatory mechanisms of protein crotonylation and the effect of crotonylation in DDR. Furthermore, the effect of protein crotonylation in tumor development and progression is presented, to inspire and explore the novel strategies for tumor therapy.
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Affiliation(s)
- Pengfei Ji
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Guokun Zhang
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Yanan Guo
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Haoyun Song
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Xinyi Yuan
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Xiaohui Hu
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Zhao Guo
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Peng Xia
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Rong Shen
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China.
| | - Degui Wang
- School of basic medical sciences, Lanzhou University, Lanzhou, Gansu Province 73000, China; NHC Key Laboratory of diagnosis and therapy of Gastrointestinal Tumor, Lanzhou, Gansu Province 730000, China.
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Cantalapiedra-Hijar G, Martinez-Fernandez G, Forano E, Denman SE, Morgavi D, McSweeney CS. The extent of nitrogen isotopic fractionation in rumen bacteria is associated with changes in rumen nitrogen metabolism. PLoS One 2023; 18:e0291243. [PMID: 37703250 PMCID: PMC10499230 DOI: 10.1371/journal.pone.0291243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 08/25/2023] [Indexed: 09/15/2023] Open
Abstract
Nitrogen use efficiency is an important index in ruminants and can be indirectly evaluated through the N isotopic discrimination between the animal and its diet (Δ15Nanimal-diet). The concentration and source of N may determine both the extent of the N isotopic discrimination in bacteria and N use efficiency. We hypothesised that the uptake and release of ammonia by rumen bacteria will affect the natural 15N enrichment of the bacterial biomass over their substrates (Δ15Nbacteria-substrate) and thereby further impacting Δ15Nanimal-diet. To test this hypothesis, two independent in vitro experiments were conducted using two contrasting N sources (organic vs inorganic) at different levels either in pure rumen bacteria culture incubations (Experiment #1) or in mixed rumen cultures (Experiment #2). In Experiment #1, tryptone casein or ammonium chloride were tested at low (1 mM N) and high (11.5 mM N) concentrations on three rumen bacterial strains (Fibrobacter succinogenes, Eubacterium limosum and Xylanibacter ruminicola) incubated in triplicate in anaerobic batch monocultures during 48h. In Experiment #2 mixed rumen cultures were incubated during 120 h with peptone or ammonium chloride at five different levels of N (1.5, 3, 4.5, 6 and 12-mM). In experiment #1, Δ15Nbacteria-substrate was lowest when the ammonia-consumer bacterium Fibrobacter succinogenes was grown on ammonium chloride, and highest when the proteolytic bacterial strain Xylanibacter ruminicola was grown on tryptone. In experiment #2, Δ15Nbacteria-substrate was lower with inorganic (ammonium chloride) vs organic (peptone) N source. A strong negative correlation between Δ15Nbacteria-substrate and Rikenellaceae_RC9_gut_group, a potential fibrolytic rumen bacterium, was detected. Together, our results showed that Δ15Nbacteria-substrate may change according to the balance between synthesis of microbial protein from ammonia versus non-ammonia N sources and confirm the key role of rumen bacteria as modulators of Δ15Nanimal-diet.
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Affiliation(s)
| | | | - Evelyne Forano
- INRAE, Université Clermont Auvergne, UMR 454 MEDIS, Saint-Genès-Champanelle, France
| | | | - Diego Morgavi
- INRAE, Université Clermont Auvergne, Vetagro Sup, UMRH, Saint-Genes-Champanelle, France
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Zhong H, Yu W, Wang M, Lin B, Sun X, Zheng N, Wang J, Zhao S. Sodium butyrate promotes gastrointestinal development of preweaning bull calves via inhibiting inflammation, balancing nutrient metabolism, and optimizing microbial community functions. ANIMAL NUTRITION (ZHONGGUO XU MU SHOU YI XUE HUI) 2023; 14:88-100. [PMID: 37388163 PMCID: PMC10300058 DOI: 10.1016/j.aninu.2023.04.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 03/26/2023] [Accepted: 04/19/2023] [Indexed: 07/01/2023]
Abstract
Butyrate promotes the growth and gastrointestinal development of calves. But, the mechanisms behind its effects on signaling pathways of the gastrointestinal tract and rumen microbiome is unclear. This study aimed to reveal transcriptomic pathways of gastrointestinal epithelium and microbial community in response to butyrate supplementation in calves fed a high fiber starter. Fourteen Holstein bull calves (39.9 ± 3.7 kg, 14 d of age) were assigned to 2 groups (sodium butyrate group, SB; control group, Ctrl). The SB group received 0.5% SB supplementation. At d 51, the calves were slaughtered to obtain samples for analysis of the transcriptome of the rumen and jejunum epithelium as well as ruminal microbial metagenome. Sodium butyrate supplementation resulted in a higher performance in average daily gain and development of jejunum and rumen papillae. In both the rumen and jejunum epithelium, SB down-regulated pathways related to inflammation including NF-κB (PPKCB, CXCL8, CXCL12), interleukin-17 (IL17A, IL17B, MMP9), and chemokine (CXCL12, CCL4, CCL8) and up-regulated immune pathways including the intestinal immune network for immunoglobulin A (IgA) production (CD28). Meanwhile, in the jejunum epithelium, SB regulated pathways related to nutritional metabolism including nitrogen metabolism (CA1, CA2, CA3), synthesis and degradation of ketone bodies (HMGCS2, BDH1, LOC100295719), fat digestion and absorption (PLA2G2F, APOA1, APOA4), and the PPAR signaling pathway (FABP4, FABP6, CYP4A11). The metagenome showed that SB greatly increased the relative abundance of Bacillus subtilis and Eubacterium limosum, activated ruminal microbial carbohydrate metabolism pathways and increased the abundance of carbohydrate hydrolysis enzymes. In conclusion, butyrate exhibited promoting effects on growth and gastrointestinal development by inhibiting inflammation, enhancing immunity and energy harvesting, and activating microbial carbohydrate metabolism. These findings provide new insights into the potential mechanisms behind the beneficial effects of butyrate in calf nutrition.
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Affiliation(s)
- Huiyue Zhong
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Wenjing Yu
- Department of Animal Science and Technology, Guangxi University, Nanning, 530005, China
| | - Min Wang
- Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
| | - Bo Lin
- Department of Animal Science and Technology, Guangxi University, Nanning, 530005, China
| | - Xuezhao Sun
- Jilin Inter-regional Cooperation Centre for the Scientific and Technological Innovation of Ruminant Precision Nutrition and Smart and Ecological Farming, Jilin Agricultural Science and Technology University, Jilin, 132109, China
- Grasslands Research Centre, AgResearch Limited, Palmerston North, New Zealand
| | - Nan Zheng
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Jiaqi Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Shengguo Zhao
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
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Zhong Q, Xiao X, Qiu Y, Xu Z, Chen C, Chong B, Zhao X, Hai S, Li S, An Z, Dai L. Protein posttranslational modifications in health and diseases: Functions, regulatory mechanisms, and therapeutic implications. MedComm (Beijing) 2023; 4:e261. [PMID: 37143582 PMCID: PMC10152985 DOI: 10.1002/mco2.261] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 03/26/2023] [Accepted: 03/27/2023] [Indexed: 05/06/2023] Open
Abstract
Protein posttranslational modifications (PTMs) refer to the breaking or generation of covalent bonds on the backbones or amino acid side chains of proteins and expand the diversity of proteins, which provides the basis for the emergence of organismal complexity. To date, more than 650 types of protein modifications, such as the most well-known phosphorylation, ubiquitination, glycosylation, methylation, SUMOylation, short-chain and long-chain acylation modifications, redox modifications, and irreversible modifications, have been described, and the inventory is still increasing. By changing the protein conformation, localization, activity, stability, charges, and interactions with other biomolecules, PTMs ultimately alter the phenotypes and biological processes of cells. The homeostasis of protein modifications is important to human health. Abnormal PTMs may cause changes in protein properties and loss of protein functions, which are closely related to the occurrence and development of various diseases. In this review, we systematically introduce the characteristics, regulatory mechanisms, and functions of various PTMs in health and diseases. In addition, the therapeutic prospects in various diseases by targeting PTMs and associated regulatory enzymes are also summarized. This work will deepen the understanding of protein modifications in health and diseases and promote the discovery of diagnostic and prognostic markers and drug targets for diseases.
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Affiliation(s)
- Qian Zhong
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Xina Xiao
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Yijie Qiu
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Zhiqiang Xu
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Chunyu Chen
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Baochen Chong
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Xinjun Zhao
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Shan Hai
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Shuangqing Li
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Zhenmei An
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
| | - Lunzhi Dai
- Department of Endocrinology and MetabolismGeneral Practice Ward/International Medical Center WardGeneral Practice Medical Center and National Clinical Research Center for GeriatricsState Key Laboratory of BiotherapyWest China Hospital, Sichuan UniversityChengduChina
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Baleeiro FCF, Varchmin L, Kleinsteuber S, Sträuber H, Neumann A. Formate-induced CO tolerance and methanogenesis inhibition in fermentation of syngas and plant biomass for carboxylate production. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:26. [PMID: 36805806 PMCID: PMC9936662 DOI: 10.1186/s13068-023-02271-w] [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: 07/01/2022] [Accepted: 01/29/2023] [Indexed: 02/19/2023]
Abstract
BACKGROUND Production of monocarboxylates using microbial communities is highly dependent on local and degradable biomass feedstocks. Syngas or different mixtures of H2, CO, and CO2 can be sourced from biomass gasification, excess renewable electricity, industrial off-gases, and carbon capture plants and co-fed to a fermenter to alleviate dependence on local biomass. To understand the effects of adding these gases during anaerobic fermentation of plant biomass, a series of batch experiments was carried out with different syngas compositions and corn silage (pH 6.0, 32 °C). RESULTS Co-fermentation of syngas with corn silage increased the overall carboxylate yield per gram of volatile solids (VS) by up to 29% (0.47 ± 0.07 g gVS-1; in comparison to 0.37 ± 0.02 g gVS-1 with a N2/CO2 headspace), despite slowing down biomass degradation. Ethylene and CO exerted a synergistic effect in preventing methanogenesis, leading to net carbon fixation. Less than 12% of the electrons were misrouted to CH4 when either 15 kPa CO or 5 kPa CO + 1.5 kPa ethylene was used. CO increased the selectivity to acetate and propionate, which accounted for 85% (electron equivalents) of all products at 49 kPa CO, by favoring lactic acid bacteria and actinobacteria over n-butyrate and n-caproate producers. Inhibition of n-butyrate and n-caproate production by CO happened even when an inoculum preacclimatized to syngas and lactate was used. Intriguingly, the effect of CO on n-butyrate and n-caproate production was reversed when formate was present in the broth. CONCLUSIONS The concept of co-fermenting syngas and plant biomass shows promise in three aspects: by making anaerobic fermentation a carbon-fixing process, by increasing the yields of short-chain carboxylates (propionate and acetate), and by minimizing electron losses to CH4. Moreover, a model was proposed for how formate can alleviate CO inhibition in certain acidogenic bacteria. Testing the fermentation of syngas and plant biomass in a continuous process could potentially improve selectivity to n-butyrate and n-caproate by enriching chain-elongating bacteria adapted to CO and complex biomass.
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Affiliation(s)
- Flávio C F Baleeiro
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
- Technical Biology, Institute of Process Engineering in Life Science, Karlsruhe Institute of Technology - KIT, Karlsruhe, Germany
| | - Lukas Varchmin
- Technical Biology, Institute of Process Engineering in Life Science, Karlsruhe Institute of Technology - KIT, Karlsruhe, Germany
| | - Sabine Kleinsteuber
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Heike Sträuber
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Anke Neumann
- Technical Biology, Institute of Process Engineering in Life Science, Karlsruhe Institute of Technology - KIT, Karlsruhe, Germany.
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10
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Sobieraj K, Stegenta-Dąbrowska S, Luo G, Koziel JA, Białowiec A. Biological treatment of biowaste as an innovative source of CO-The role of composting process. Front Bioeng Biotechnol 2023; 11:1126737. [PMID: 36845185 PMCID: PMC9947533 DOI: 10.3389/fbioe.2023.1126737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 01/30/2023] [Indexed: 02/11/2023] Open
Abstract
Carbon monoxide (CO) is an essential "building block" for producing everyday chemicals on industrial scale. Carbon monoxide can also be generated though a lesser-known and sometimes forgotten biorenewable pathways that could be explored to advance biobased production from large and more sustainable sources such as bio-waste treatment. Organic matter decomposition can generate carbon monoxide both under aerobic and anaerobic conditions. While anaerobic carbon monoxide generation is relatively well understood, the aerobic is not. Yet many industrial-scale bioprocesses involve both conditions. This review summarizes the necessary basic biochemistry knowledge needed for realization of initial steps towards biobased carbon monoxide production. We analyzed for the first time, the complex information about carbon monoxide production during aerobic, anaerobic bio-waste treatment and storage, carbon monoxide-metabolizing microorganisms, pathways, and enzymes with bibliometric analysis of trends. The future directions recognizing limitations of combined composting and carbon monoxide production have been discussed in greater detail.
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Affiliation(s)
- Karolina Sobieraj
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Sylwia Stegenta-Dąbrowska
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Gang Luo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai, China,Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai, China,Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China
| | - Jacek A. Koziel
- USDA-ARS Conservation and Production Research Laboratory, Bushland, TX, United States,Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, United States
| | - Andrzej Białowiec
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, Wrocław, Poland,Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, United States,*Correspondence: Andrzej Białowiec,
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11
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Genome-wide CRISPRi screen identifies enhanced autolithotrophic phenotypes in acetogenic bacterium Eubacterium limosum. Proc Natl Acad Sci U S A 2023; 120:e2216244120. [PMID: 36716373 PMCID: PMC9963998 DOI: 10.1073/pnas.2216244120] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Acetogenic bacteria are a unique biocatalyst that highly promises to develop the sustainable bioconversion of carbon oxides (e.g., CO and CO2) into multicarbon biochemicals. Genotype-phenotype relationships are important for engineering their metabolic capability to enhance their biocatalytic performance; however, systemic investigation on the fitness contribution of individual gene has been limited. Here, we report genome-scale CRISPR interference screening using 41,939 guide RNAs designed from the E. limosum genome, one of the model acetogenic species, where all genes were targeted for transcriptional suppression. We investigated the fitness contributions of 96% of the total genes identified, revealing the gene fitness and essentiality for heterotrophic and autotrophic metabolisms. Our data show that the Wood-Ljungdahl pathway, membrane regeneration, membrane protein biosynthesis, and butyrate synthesis are essential for autotrophic acetogenesis in E. limosum. Furthermore, we discovered genes that are repression targets that unbiasedly increased autotrophic growth rates fourfold and acetoin production 1.5-fold compared to the wild-type strain under CO2-H2 conditions. These results provide insight for understanding acetogenic metabolism and genome engineering in acetogenic bacteria.
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12
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Shang S, Liu J, Hua F. Protein acylation: mechanisms, biological functions and therapeutic targets. Signal Transduct Target Ther 2022; 7:396. [PMID: 36577755 PMCID: PMC9797573 DOI: 10.1038/s41392-022-01245-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 09/27/2022] [Accepted: 11/06/2022] [Indexed: 12/30/2022] Open
Abstract
Metabolic reprogramming is involved in the pathogenesis of not only cancers but also neurodegenerative diseases, cardiovascular diseases, and infectious diseases. With the progress of metabonomics and proteomics, metabolites have been found to affect protein acylations through providing acyl groups or changing the activities of acyltransferases or deacylases. Reciprocally, protein acylation is involved in key cellular processes relevant to physiology and diseases, such as protein stability, protein subcellular localization, enzyme activity, transcriptional activity, protein-protein interactions and protein-DNA interactions. Herein, we summarize the functional diversity and mechanisms of eight kinds of nonhistone protein acylations in the physiological processes and progression of several diseases. We also highlight the recent progress in the development of inhibitors for acyltransferase, deacylase, and acylation reader proteins for their potential applications in drug discovery.
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Affiliation(s)
- Shuang Shang
- grid.506261.60000 0001 0706 7839CAMS Key Laboratory of Molecular Mechanism and Target Discovery of Metabolic Disorder and Tumorigenesis, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, 100050 Beijing, P.R. China
| | - Jing Liu
- grid.506261.60000 0001 0706 7839CAMS Key Laboratory of Molecular Mechanism and Target Discovery of Metabolic Disorder and Tumorigenesis, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, 100050 Beijing, P.R. China
| | - Fang Hua
- grid.506261.60000 0001 0706 7839CAMS Key Laboratory of Molecular Mechanism and Target Discovery of Metabolic Disorder and Tumorigenesis, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, 100050 Beijing, P.R. China
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13
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Yoon J, Bae J, Kang S, Cho BK, Oh MK. Poly-3-hydroxybutyrate production in acetate minimal medium using engineered Methylorubrum extorquens AM1. BIORESOURCE TECHNOLOGY 2022; 353:127127. [PMID: 35398538 DOI: 10.1016/j.biortech.2022.127127] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/03/2022] [Accepted: 04/05/2022] [Indexed: 06/14/2023]
Abstract
Acetate is regarded as a sustainable microbial feedstock that is synthesized from biowastes such as synthesis gas (syngas), carbon dioxide, lignocellulose, or organic waste. In this study, Methylorubrum extorquens AM1 was engineered to improve the production of bioplastic poly-3-hydroxybutyrate (PHB) using acetate as the sole carbon source. To utilize acetate as a carbon source and methanol as an energy source, acs encoding acetyl-CoA synthetase and fdh from Burkholderia stabilis were overexpressed, while ftfL involved in the assimilation of methanol into formyl-tetrahydrofolate was deleted. The yields of biomass and PHB from acetate significantly improved, and the growth rate and PHB content of the bacteria increased. In addition, sustainability of the PHB production was demonstrated using acetate derived from carbon dioxide and syngas. This study shows that biopolymers could be synthesized efficiently using acetate as the sole carbon source through metabolic engineering and the supply of energy cofactors.
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Affiliation(s)
- Jihee Yoon
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jiyun Bae
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Seulgi Kang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, 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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14
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Bajracharya S, Krige A, Matsakas L, Rova U, Christakopoulos P. Advances in cathode designs and reactor configurations of microbial electrosynthesis systems to facilitate gas electro-fermentation. BIORESOURCE TECHNOLOGY 2022; 354:127178. [PMID: 35436538 DOI: 10.1016/j.biortech.2022.127178] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 06/14/2023]
Abstract
In gas fermentation, a range of chemolithoautotrophs fix single-carbon (C1) gases (CO2 and CO) when H2 or other reductants are available. Microbial electrosynthesis (MES) enables CO2 reduction by generating H2 or reducing equivalents with the sole input of renewable electricity. A combined approach as gas electro-fermentation is attractive for the sustainable production of biofuels and biochemicals utilizing C1 gases. Various platform compounds such as acetate, butyrate, caproate, ethanol, butanol and bioplastics can be produced. However, technological challenges pertaining to the microbe-material interactions such as poor gas-liquid mass transfer, low biomass and biofilm coverage on cathode, low productivities still exist. We are presenting a review on latest developments in MES focusing on the configuration and design of cathodes that can address the challenges and support the gas electro-fermentation. Overall, the opportunities for advancing CO and CO2-based biochemicals and biofuels production in MES with suitable cathode/reactor design are prospected.
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Affiliation(s)
- Suman Bajracharya
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden.
| | - Adolf Krige
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
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15
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ATP synthesis in an ancient ATP synthase at low driving forces. Proc Natl Acad Sci U S A 2022; 119:e2201921119. [PMID: 35512103 DOI: 10.1073/pnas.2201921119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SignificanceThe ATP synthases of many anaerobic archaea have an unusual motor subunit c that otherwise is only found in eukaryotic V1VO ATPases. The evolutionary switch from synthase to hydrolase is thought to be caused by a doubling of the rotor subunit c, followed by a loss of the ion binding site. By purification and reconstitution of an ATP synthase with a V-type c subunit, we have unequivocally demonstrated, against expectations, the capability of such an enzyme to synthesize ATP at physiological relevant driving forces of 90 to 150 mV. This is the long-awaited answer to an eminent question in microbial energetics and physiology, especially for life near the thermodynamic limit of ATP synthesis.
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16
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Lee H, Bae J, Jin S, Kang S, Cho BK. Engineering Acetogenic Bacteria for Efficient One-Carbon Utilization. Front Microbiol 2022; 13:865168. [PMID: 35615514 PMCID: PMC9124964 DOI: 10.3389/fmicb.2022.865168] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 04/19/2022] [Indexed: 12/03/2022] Open
Abstract
C1 gases, including carbon dioxide (CO2) and carbon monoxide (CO), are major contributors to climate crisis. Numerous studies have been conducted to fix and recycle C1 gases in order to solve this problem. Among them, the use of microorganisms as biocatalysts to convert C1 gases to value-added chemicals is a promising solution. Acetogenic bacteria (acetogens) have received attention as high-potential biocatalysts owing to their conserved Wood–Ljungdahl (WL) pathway, which fixes not only CO2 but also CO. Although some metabolites have been produced via C1 gas fermentation on an industrial scale, the conversion of C1 gases to produce various biochemicals by engineering acetogens has been limited. The energy limitation of acetogens is one of the challenges to overcome, as their metabolism operates at a thermodynamic limit, and the low solubility of gaseous substrates results in a limited supply of cellular energy. This review provides strategies for developing efficient platform strains for C1 gas conversion, focusing on engineering the WL pathway. Supplying liquid C1 substrates, which can be obtained from CO2, or electricity is introduced as a strategy to overcome the energy limitation. Future prospective approaches on engineering acetogens based on systems and synthetic biology approaches are also discussed.
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Affiliation(s)
- Hyeonsik Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Jiyun Bae
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Sangrak Jin
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Seulgi Kang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
- KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
- *Correspondence: Byung-Kwan Cho,
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17
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Liu C, Ji J, Wu W, Arhin SG, Papadakis VG, Goula MA, Zhang S, Zhang Y, Wang W. Heterogeneous Catalyst–Microbiome Hybrids for Efficient CO-Driven C6 Carboxylic Acid Synthesis via Metabolic Pathway Manipulation. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Chao Liu
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing 100029, China
| | - Jiacheng Ji
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Wanling Wu
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing 100029, China
| | - Samuel Gyebi Arhin
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing 100029, China
| | - Vagelis G. Papadakis
- Department of Environmental Engineering, University of Patras, Agrinio 30100, Greece
| | - Maria A. Goula
- Laboratory of Alternative Fuels and Environmental Catalysis, Department of Chemical Engineering, University of Western Macedonia, Kozani 50100, Greece
| | - Sanpeng Zhang
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yi Zhang
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Wen Wang
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing 100029, China
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18
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Biosynthesis of butyrate from methanol and carbon monoxide by recombinant Acetobacterium woodii. Int Microbiol 2022; 25:551-560. [PMID: 35179672 PMCID: PMC9307552 DOI: 10.1007/s10123-022-00234-z] [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: 09/17/2021] [Revised: 12/21/2021] [Accepted: 01/11/2022] [Indexed: 10/27/2022]
Abstract
Methanol is one of the most widely produced organic substrates from syngas and can serve as a bio-feedstock to cultivate acetogenic bacteria which allows a major contribution to reducing greenhouse gas. Acetobacterium woodii is one of the very few acetogens that can utilize methanol to produce acetate as sole product. Since A. woodii is genetically tractable, it is an interesting candidate to introduce recombinant pathways for production of bio-commodities from methanol. In this study, we introduced the butyrate production operon from a related acetogen, Eubacterium callanderi KIST612, into A. woodii and show a stable production of butyrate from methanol. This study also reveals how butyrate production by recombinant A. woodii strains can be enhanced with addition of electrons in the form of carbon monoxide. Our results not only show a stable expression system of non-native enzymes in A. woodii but also increase in the product spectrum of A. woodii to compounds with higher economic value.
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19
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Systems Biology on Acetogenic Bacteria for Utilizing C1 Feedstocks. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2022; 180:57-90. [DOI: 10.1007/10_2021_199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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20
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Biological conversion of carbon monoxide and hydrogen by anaerobic culture: Prospect of anaerobic digestion and thermochemical processes combination. Biotechnol Adv 2021; 58:107886. [PMID: 34915147 DOI: 10.1016/j.biotechadv.2021.107886] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/26/2021] [Accepted: 12/08/2021] [Indexed: 01/04/2023]
Abstract
Waste biomass is considered a promising renewable energy feedstock that can be converted by anaerobic digestion. However, anaerobic digestion application can be challenging due to the structural complexity of several waste biomass kinds. Therefore, coupling anaerobic digestion with thermochemical processes can offset the limitations and convert the hardly biodegradable waste biomass, including digestate residue, into value-added products: syngas and pyrogas (gaseous mixtures consisting mainly of H2, CO, CO2), bio-oil, and biochar for further valorisation. In this review, the utilisation boundaries and benefits of the aforementioned products by anaerobic culture are discussed. First, thermochemical process parameters for an enhanced yield of desired products are summarised. Particularly, the microbiology of CO and H2 mixture biomethanation and fermentation in anaerobic digestion is presented. Finally, the state-of-the-art biological conversion of syngas and pyrogas to CH4 mediated by anaerobic culture is adequately described. Extensive research shows the successful selective biological conversion of CO and H2 to CH4, acetic acid, and alcohols. The main bottleneck is the gas-liquid mass transfer which can be enhanced appropriately by bioreactors' configurations. A few research groups focus on bio-oil and biochar addition into anaerobic digesters. However, according to the literature review, there has been no research for utilising all value-added products at once in anaerobic digestion published so far. Although synergic effects of such can be expected. In summary, the combination of anaerobic digestion and thermochemical processes is a promising alternative for wide-scale waste biomass utilisation in practice.
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21
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Kang H, Park B, Oh S, Pathiraja D, Kim JY, Jung S, Jeong J, Cha M, Park ZY, Choi IG, Chang IS. Metabolism perturbation Causedby the overexpression of carbon monoxide dehydrogenase/Acetyl-CoA synthase gene complex accelerated gas to acetate conversion rate ofEubacterium limosumKIST612. BIORESOURCE TECHNOLOGY 2021; 341:125879. [PMID: 34523550 DOI: 10.1016/j.biortech.2021.125879] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
Microbial conversion of carbon monoxide (CO) to acetate is a promising upcycling strategy for carbon sequestration. Herein, we demonstrate that CO conversion and acetate production rates of Eubacterium limosum KIST612 strain can be improved by in silico prediction and in vivo assessment. The mimicked CO metabolic model of KIST612 predicted that overexpressing the CO dehydrogenase (CODH) increases CO conversion and acetate production rates. To validate the prediction, we constructed mutant strains overexpressing CODH gene cluster and measured their CO conversion and acetate production rates. A mutant strain (ELM031) co-overexpressing CODH, coenzyme CooC2 and ACS showed a 3.1 × increased specific CO oxidation rate as well as 1.4 × increased specific acetate production rate, compared to the wild type strain. The transcriptional and translational data with redox balance analysis showed that ELM031 has enhanced reducing potential from up-regulation of ferredoxin and related metabolism directly linked to energy conservation.
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Affiliation(s)
- Hyunsoo Kang
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Byeonghyeok Park
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Soyoung Oh
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Duleepa Pathiraja
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Ji-Yeon Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Seunghyeon Jung
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Jiyeong Jeong
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Minseok Cha
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Zee-Yong Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - In-Geol Choi
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - In Seop Chang
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.
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22
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Wood JC, Marcellin E, Plan MR, Virdis B. High methanol-to-formate ratios induce butanol production in Eubacterium limosum. Microb Biotechnol 2021; 15:1542-1549. [PMID: 34841673 PMCID: PMC9049608 DOI: 10.1111/1751-7915.13963] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 10/06/2021] [Accepted: 10/20/2021] [Indexed: 11/29/2022] Open
Abstract
Unlike gaseous C1 feedstocks for acetogenic bacteria, there has been less attention on liquid C1 feedstocks, despite benefits in terms of energy efficiency, mass transfer and integration within existing fermentation infrastructure. Here, we present growth of Eubacterium limosum ATCC8486 using methanol and formate as substrates, finding evidence for the first time of native butanol production. We varied ratios of methanol‐to‐formate in batch serum bottle fermentations, showing butyrate is the major product (maximum specific rate 220 ± 23 mmol‐C gDCW‐1day‐1). Increasing this ratio showed methanol is the key feedstock driving the product spectrum towards more reduced products, such as butanol (maximum titre 2.0 ± 1.1 mM‐C). However, both substrates are required for a high growth rate (maximum 0.19 ± 0.011 h‐1) and cell density (maximum 1.2 ± 0.043 gDCW l‐1), with formate being the preferred substrate. In fact, formate and methanol are consumed in two distinct growth phases – growth phase 1, on predominately formate and growth phase 2 on methanol, which must balance. Because the second growth varied according to the first growth on formate, this suggests butanol production is due to overflow metabolism, similar to 2,3‐butanediol production in other acetogens. However, further research is required to confirm the butanol production pathway in E. limosum, particularly given, unlike other substrates, methanol likely results in mostly NADH generation, not reduced ferredoxin.
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Affiliation(s)
- Jamin C Wood
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, Brisbane, Qld, 4072, Australia
| | - Esteban Marcellin
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Qld, 4072, Australia.,Metabolomics Australia (Queensland node), The University of Queensland, Brisbane, Qld, 4072, Australia
| | - Manuel R Plan
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Qld, 4072, Australia.,Metabolomics Australia (Queensland node), The University of Queensland, Brisbane, Qld, 4072, Australia
| | - Bernardino Virdis
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, Brisbane, Qld, 4072, Australia
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23
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Litty D, Müller V. Butyrate production in the acetogen Eubacterium limosum is dependent on the carbon and energy source. Microb Biotechnol 2021; 14:2686-2692. [PMID: 33629808 PMCID: PMC8601167 DOI: 10.1111/1751-7915.13779] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/09/2021] [Accepted: 02/09/2021] [Indexed: 11/29/2022] Open
Abstract
Eubacterium limosum KIST612 is one of the few acetogenic bacteria that has the genes encoding for butyrate synthesis from acetyl-CoA, and indeed, E. limosum KIST612 is known to produce butyrate from CO but not from H2 + CO2 . Butyrate production from CO was only seen in bioreactors with cell recycling or in batch cultures with addition of acetate. Here, we present detailed study on growth of E. limosum KIST612 on different carbon and energy sources with the goal, to find other substrates that lead to butyrate formation. Batch fermentations in serum bottles revealed that acetate was the major product under all conditions investigated. Butyrate formation from the C1 compounds carbon dioxide and hydrogen, carbon monoxide or formate was not observed. However, growth on glucose led to butyrate formation, but only in the stationary growth phase. A maximum of 4.3 mM butyrate was observed, corresponding to a butyrate:glucose ratio of 0.21:1 and a butyrate:acetate ratio of 0.14:1. Interestingly, growth on the C1 substrate methanol also led to butyrate formation in the stationary growth phase with a butyrate:methanol ratio of 0.17:1 and a butyrate:acetate ratio of 0.33:1. Since methanol can be produced chemically from carbon dioxide, this offers the possibility for a combined chemical-biochemical production of butyrate from H2 + CO2 using this acetogenic biocatalyst. With the advent of genetic methods in acetogens, butanol production from methanol maybe possible as well.
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Affiliation(s)
- Dennis Litty
- Department of Molecular Microbiology & BioenergeticsInstitute of Molecular BiosciencesGoethe‐University Frankfurt am MainHessenGermany
| | - Volker Müller
- Department of Molecular Microbiology & BioenergeticsInstitute of Molecular BiosciencesGoethe‐University Frankfurt am MainHessenGermany
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24
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Electron carriers involved in autotrophic and heterotrophic acetogenesis in the thermophilic bacterium Thermoanaerobacter kivui. Extremophiles 2021; 25:513-526. [PMID: 34647163 PMCID: PMC8578170 DOI: 10.1007/s00792-021-01247-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/27/2021] [Indexed: 12/05/2022]
Abstract
Thermoanaerobacter kivui is an acetogenic model organism that reduces CO2 with electrons derived from H2 or CO, or from organic substrates in the Wood–Ljugdahl pathway (WLP). For the calculation of ATP yields, it is necessary to know the electron carriers involved in coupling of the oxidative and reductive parts of metabolism. Analyses of key catabolic oxidoreductases in cell-free extract (CFE) or with purified enzymes revealed the physiological electron carriers involved. The glyceraldehyde-3-phosphate dehydrogenase (GA3P-DH) assayed in CFE was NAD+-specific, NADP+ was used with less than 4% and ferredoxin (Fd) was not used. The methylene-THF dehydrogenase was NADP+-specific, NAD+ or Fd were not used. A Nfn-type transhydrogenase that catalyzes reduced Fd-dependent reduction of NADP+ with NADH as electron donor was also identified in CFE. The electron carriers used by the potential electron-bifurcating hydrogenase (HydABC) could not be unambiguously determined in CFE for technical reasons. Therefore, the enzyme was produced homologously in T. kivui and purified by affinity chromatography. HydABC contained 33.9 ± 4.5 mol Fe/mol of protein and FMN; it reduced NADP+ but not NAD+. The methylene-THF reductase (MetFV) was also produced homologously in T. kivui and purified by affinity chromatography. MetFV contained 7.2 ± 0.4 mol Fe/mol of protein and FMN; the complex did neither use NADPH nor NADH as reductant but only reduced Fd. In sum, these analysis allowed us to propose a scheme for entire electron flow and bioenergetics in T. kivui.
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Kremp F, Müller V. Methanol and methyl group conversion in acetogenic bacteria: biochemistry, physiology and application. FEMS Microbiol Rev 2021; 45:5903270. [PMID: 32901799 DOI: 10.1093/femsre/fuaa040] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 08/29/2020] [Indexed: 12/24/2022] Open
Abstract
The production of bulk chemicals mostly depends on exhausting petroleum sources and leads to emission of greenhouse gases. Within the last decades the urgent need for alternative sources has increased and the development of bio-based processes received new attention. To avoid the competition between the use of sugars as food or fuel, other feedstocks with high availability and low cost are needed, which brought acetogenic bacteria into focus. This group of anaerobic organisms uses mixtures of CO2, CO and H2 for the production of mostly acetate and ethanol. Also methanol, a cheap and abundant bulk chemical produced from methane, is a suitable substrate for acetogenic bacteria. In methylotrophic acetogens the methyl group is transferred to the Wood-Ljungdahl pathway, a pathway to reduce CO2 to acetate via a series of C1-intermediates bound to tetrahydrofolic acid. Here we describe the biochemistry and bioenergetics of methanol conversion in the biotechnologically interesting group of anaerobic, acetogenic bacteria. Further, the bioenergetics of biochemical production from methanol is discussed.
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Affiliation(s)
- Florian Kremp
- Department of Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, D-60438 Frankfurt, Germany
| | - Volker Müller
- Department of Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, D-60438 Frankfurt, Germany
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26
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Abstract
Acetogens synthesize acetyl-CoA via the CO2-fixing Wood-Ljungdahl pathway. Despite their ecological and biotechnological importance, their translational regulation of carbon and energy metabolisms remains unclear. Here, we report how carbon and energy metabolisms in the model acetogen Acetobacterium woodii are translationally controlled under different growth conditions. Data integration of genome-scale transcriptomic and translatomic analyses revealed that the acetogenesis genes, including those of the Wood-Ljungdahl pathway and energy metabolism, showed changes in translational efficiency under autotrophic growth conditions. In particular, genes encoding the Wood-Ljungdahl pathway are translated at similar levels to achieve efficient acetogenesis activity under autotrophic growth conditions, whereas genes encoding the carbonyl branch present increased translation levels in comparison to those for the methyl branch under heterotrophic growth conditions. The translation efficiency of genes in the pathways is differentially regulated by 5′ untranslated regions and ribosome-binding sequences under different growth conditions. Our findings provide potential strategies to optimize the metabolism of syngas-fermenting acetogenic bacteria for better productivity. IMPORTANCE Acetogens are capable of reducing CO2 to multicarbon compounds (e.g., ethanol or 2,3-butanediol) via the Wood-Ljungdahl pathway. Given that protein synthesis in bacteria is highly energy consuming, acetogens living at the thermodynamic limit of life are inevitably under translation control. Here, we dissect the translational regulation of carbon and energy metabolisms in the model acetogen Acetobacterium woodii under heterotrophic and autotrophic growth conditions. The latter may be experienced when acetogen is used as a cell factory that synthesizes products from CO2 during the gas fermentation process. We found that the methyl and carbonyl branches of the Wood-Ljungdahl pathway are activated at similar translation levels during autotrophic growth. Translation is mainly regulated by the 5′-untranslated-region structure and ribosome-binding-site sequence. This work reveals novel translational regulation for coping with autotrophic growth conditions and provides the systematic data set, including the transcriptome, translatome, and promoter/5′-untranslated-region bioparts.
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Jiang G, Li C, Lu M, Lu K, Li H. Protein lysine crotonylation: past, present, perspective. Cell Death Dis 2021; 12:703. [PMID: 34262024 PMCID: PMC8280118 DOI: 10.1038/s41419-021-03987-z] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/28/2021] [Accepted: 05/31/2021] [Indexed: 02/08/2023]
Abstract
Lysine crotonylation has been discovered in histone and non-histone proteins and found to be involved in diverse diseases and biological processes, such as neuropsychiatric disease, carcinogenesis, spermatogenesis, tissue injury, and inflammation. The unique carbon–carbon π-bond structure indicates that lysine crotonylation may use distinct regulatory mechanisms from the widely studied other types of lysine acylation. In this review, we discussed the regulation of lysine crotonylation by enzymatic and non-enzymatic mechanisms, the recognition of substrate proteins, the physiological functions of lysine crotonylation and its cross-talk with other types of modification. The tools and methods for prediction and detection of lysine crotonylation were also described.
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Affiliation(s)
- Gaoyue Jiang
- West China Second University Hospital, State Key Laboratory of Biotherapy, and Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, 610041, Chengdu, China
| | - Chunxia Li
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and The Research Units of West China, Chinese Academy of Medical Sciences, Chengdu, China
| | - Meng Lu
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and The Research Units of West China, Chinese Academy of Medical Sciences, Chengdu, China
| | - Kefeng Lu
- Department of Neurosurgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and The Research Units of West China, Chinese Academy of Medical Sciences, Chengdu, China.
| | - Huihui Li
- West China Second University Hospital, State Key Laboratory of Biotherapy, and Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, 610041, Chengdu, China.
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Dietrich HM, Kremp F, Öppinger C, Ribaric L, Müller V. Biochemistry of methanol-dependent acetogenesis in Eubacterium callanderi KIST612. Environ Microbiol 2021; 23:4505-4517. [PMID: 34125457 DOI: 10.1111/1462-2920.15643] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/13/2021] [Indexed: 11/26/2022]
Abstract
Methanol is the simplest of all alcohols, is universally distributed in anoxic sediments as a result of plant material decomposition and is constantly attracting attention as an interesting substrate for anaerobes like acetogens that can convert bio-renewable methanol into value-added chemicals. A major drawback in the development of environmentally friendly but economically attractive biotechnological processes is the present lack of information on biochemistry and bioenergetics during methanol conversion in these bacteria. The mesophilic acetogen Eubacterium callanderi KIST612 is naturally able to consume methanol and produce acetate as well as butyrate. To grasp the full potential of methanol-based production of chemicals, we analysed the genes and enzymes involved in methanol conversion to acetate and identified the redox carriers involved. We will display a complete model for methanol-derived acetogenesis and butyrogenesis in Eubacterium callanderi KIST612, tracing the electron transfer routes and shed light on the bioenergetics during the process.
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Affiliation(s)
- Helge M Dietrich
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
| | - Florian Kremp
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
| | - Christian Öppinger
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
| | - Luna Ribaric
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
| | - Volker Müller
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
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29
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Schwarz FM, Ciurus S, Jain S, Baum C, Wiechmann A, Basen M, Müller V. Revealing formate production from carbon monoxide in wild type and mutants of Rnf- and Ech-containing acetogens, Acetobacterium woodii and Thermoanaerobacter kivui. Microb Biotechnol 2020; 13:2044-2056. [PMID: 32959527 PMCID: PMC7533326 DOI: 10.1111/1751-7915.13663] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 01/18/2023] Open
Abstract
Acetogenic bacteria have gained much attraction in recent years as they can produce different biofuels and biochemicals from H2 plus CO2 or even CO alone, therefore opening a promising alternative route for the production of biofuels from renewable sources compared to existing sugar-based routes. However, CO metabolism still raises questions concerning the biochemistry and bioenergetics in many acetogens. In this study, we focused on the two acetogenic bacteria Acetobacterium woodii and Thermoanaerobacter kivui which, so far, are the only identified acetogens harbouring a H2 -dependent CO2 reductase and furthermore belong to different classes of 'Rnf'- and 'Ech-acetogens'. Both strains catalysed the conversion of CO into the bulk chemical acetate and formate. Formate production was stimulated by uncoupling the energy metabolism from the Wood-Ljungdahl pathway, and specific rates of 1.44 and 1.34 mmol g-1 h-1 for A. woodii ∆rnf and T. kivui wild type were reached. The demonstrated CO-based formate production rates are, to the best of our knowledge, among the highest rates ever reported. Using mutants of ∆hdcr, ∆cooS, ∆hydBA, ∆rnf and ∆ech2 with deficiencies in key enzyme activities of the central metabolism enabled us to postulate two different CO utilization pathways in these two model organisms.
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Affiliation(s)
- Fabian M. Schwarz
- Molecular Microbiology and BioenergeticsInstitute of Molecular BiosciencesJohann Wolfgang Goethe UniversityFrankfurt am MainGermany
| | - Sarah Ciurus
- Molecular Microbiology and BioenergeticsInstitute of Molecular BiosciencesJohann Wolfgang Goethe UniversityFrankfurt am MainGermany
| | - Surbhi Jain
- Molecular Microbiology and BioenergeticsInstitute of Molecular BiosciencesJohann Wolfgang Goethe UniversityFrankfurt am MainGermany
| | - Christoph Baum
- MicrobiologyInstitute of Biological SciencesUniversity RostockRostockGermany
| | - Anja Wiechmann
- Molecular Microbiology and BioenergeticsInstitute of Molecular BiosciencesJohann Wolfgang Goethe UniversityFrankfurt am MainGermany
| | - Mirko Basen
- MicrobiologyInstitute of Biological SciencesUniversity RostockRostockGermany
| | - Volker Müller
- Molecular Microbiology and BioenergeticsInstitute of Molecular BiosciencesJohann Wolfgang Goethe UniversityFrankfurt am MainGermany
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30
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Vees CA, Neuendorf CS, Pflügl S. Towards continuous industrial bioprocessing with solventogenic and acetogenic clostridia: challenges, progress and perspectives. J Ind Microbiol Biotechnol 2020; 47:753-787. [PMID: 32894379 PMCID: PMC7658081 DOI: 10.1007/s10295-020-02296-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 07/20/2020] [Indexed: 12/11/2022]
Abstract
The sustainable production of solvents from above ground carbon is highly desired. Several clostridia naturally produce solvents and use a variety of renewable and waste-derived substrates such as lignocellulosic biomass and gas mixtures containing H2/CO2 or CO. To enable economically viable production of solvents and biofuels such as ethanol and butanol, the high productivity of continuous bioprocesses is needed. While the first industrial-scale gas fermentation facility operates continuously, the acetone-butanol-ethanol (ABE) fermentation is traditionally operated in batch mode. This review highlights the benefits of continuous bioprocessing for solvent production and underlines the progress made towards its establishment. Based on metabolic capabilities of solvent producing clostridia, we discuss recent advances in systems-level understanding and genome engineering. On the process side, we focus on innovative fermentation methods and integrated product recovery to overcome the limitations of the classical one-stage chemostat and give an overview of the current industrial bioproduction of solvents.
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Affiliation(s)
- Charlotte Anne Vees
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
| | - Christian Simon Neuendorf
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
| | - Stefan Pflügl
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
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31
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Kountz DJ, Behrman EJ, Zhang L, Krzycki JA. MtcB, a member of the MttB superfamily from the human gut acetogen Eubacterium limosum, is a cobalamin-dependent carnitine demethylase. J Biol Chem 2020; 295:11971-11981. [PMID: 32571881 PMCID: PMC7443480 DOI: 10.1074/jbc.ra120.012934] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 06/18/2020] [Indexed: 12/22/2022] Open
Abstract
The trimethylamine methyltransferase MttB is the first described member of a superfamily comprising thousands of microbial proteins. Most members of the MttB superfamily are encoded by genes that lack the codon for pyrrolysine characteristic of trimethylamine methyltransferases, raising questions about the activities of these proteins. The superfamily member MtcB is found in the human intestinal isolate Eubacterium limosum ATCC 8486, an acetogen that can grow by demethylation of l-carnitine. Here, we demonstrate that MtcB catalyzes l-carnitine demethylation. When growing on l-carnitine, E. limosum excreted the unusual biological product norcarnitine as well as acetate, butyrate, and caproate. Cellular extracts of E. limosum grown on l-carnitine, but not lactate, methylated cob-(I)alamin or tetrahydrofolate using l-carnitine as methyl donor. MtcB, along with the corrinoid protein MtqC and the methylcorrinoid:tetrahydrofolate methyltransferase MtqA, were much more abundant in E. limosum cells grown on l-carnitine than on lactate. Recombinant MtcB methylates either cob(I)alamin or Co(I)-MtqC in the presence of l-carnitine and, to a much lesser extent, γ-butyrobetaine. Other quaternary amines were not substrates. Recombinant MtcB, MtqC, and MtqA methylated tetrahydrofolate via l-carnitine, forming a key intermediate in the acetogenic Wood-Ljungdahl pathway. To our knowledge, MtcB methylation of cobalamin or Co(I)-MtqC represents the first described mechanism of biological l-carnitine demethylation. The conversion of l-carnitine and its derivative γ-butyrobetaine to trimethylamine by the gut microbiome has been linked to cardiovascular disease. The activities of MtcB and related proteins in E. limosum might demethylate proatherogenic quaternary amines and contribute to the perceived health benefits of this human gut symbiont.
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Affiliation(s)
- Duncan J Kountz
- Department of Microbiology, Ohio State University, Columbus, Ohio, USA
| | - Edward J Behrman
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, Ohio, USA
| | - Liwen Zhang
- Campus Chemical Instrument Center Mass Spectrometry and Proteomics Facility, Ohio State University, Columbus, Ohio, USA
| | - Joseph A Krzycki
- Department of Microbiology, Ohio State University, Columbus, Ohio, USA; Ohio State Biochemistry Program, Ohio State University, Columbus, Ohio, USA.
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32
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Moens E, Bolca S, Van de Wiele T, Van Landschoot A, Goeman JL, Possemiers S, Verstraete W. Exploration of isoxanthohumol bioconversion from spent hops into 8-prenylnaringenin using resting cells of Eubacterium limosum. AMB Express 2020; 10:79. [PMID: 32333233 PMCID: PMC7182650 DOI: 10.1186/s13568-020-01015-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 04/17/2020] [Indexed: 11/10/2022] Open
Abstract
Hops is an almost unique source of the potent phytoestrogen 8-prenylnaringenin (8-PN). As hops contain only low levels of 8-PN, synthesis may be more attractive than extraction. A strain of the Gram-positive Eubacterium limosum was isolated previously for 8-PN production from more abundant precursor isoxanthohumol (IX) from hops. In this study, spent hops, an industrial side stream from the beer industry, was identified as interesting source of IX. Yet, hop-derived compounds are well-known antibacterial agents and the traces of a large variety of different compounds in spent hops interfered with growth and IX conversion. Critical factors to finally enable bacterial 8-PN production from spent hops, using a food and feed grade medium, were evaluated in this research. The use of bacterial resting cells and complex medium at a pH of 7.8-8 best fulfilled the requirements for 8-PN production and generated a solid basis for development of an economic process.
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Affiliation(s)
- Esther Moens
- ProDigest BVBA, Technol Pk 82, 9052, Ghent, Belgium
- Ugent, CMET, Coupure Links 653, 9000, Ghent, Belgium
| | - Selin Bolca
- ProDigest BVBA, Technol Pk 82, 9052, Ghent, Belgium
| | | | | | - Jan L Goeman
- Ugent, Dept Organic and Macromolecular Chemistry, Krijgslaan 281-S4, 9000, Ghent, Belgium
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33
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Open microbiome dominated by Clostridium and Eubacterium converts methanol into i-butyrate and n-butyrate. Appl Microbiol Biotechnol 2020; 104:5119-5131. [PMID: 32248436 DOI: 10.1007/s00253-020-10551-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 02/29/2020] [Accepted: 03/15/2020] [Indexed: 12/14/2022]
Abstract
Isobutyrate (i-butyrate) is a versatile platform chemical, whose acid form is used as a precursor of plastic and emulsifier. It can be produced microbially either using genetically engineered organisms or via microbiomes, in the latter case starting from methanol and short-chain carboxylates. This opens the opportunity to produce i-butyrate from non-sterile feedstocks. Little is known on the ecology and process conditions leading to i-butyrate production. In this study, we steered i-butyrate production in a bioreactor fed with methanol and acetate under various conditions, achieving maximum i-butyrate productivity of 5.0 mM day-1, with a concurrent production of n-butyrate of 7.9 mM day-1. The production of i-butyrate was reversibly inhibited by methanogenic inhibitor 2-bromoethanesulfonate. The microbial community data revealed the co-dominance of two major OTUs during co-production of i-butyrate and n-butyrate in two distinctive phases throughout a period of 54 days and 28 days, respectively. The cross-comparison of product profile with microbial community composition suggests that the relative abundance of Clostridium sp. over Eubacterium sp. is correlated with i-butyrate productivity over n-butyrate productivity.
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34
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Kang S, Song Y, Jin S, Shin J, Bae J, Kim DR, Lee JK, Kim SC, Cho S, Cho BK. Adaptive Laboratory Evolution of Eubacterium limosum ATCC 8486 on Carbon Monoxide. Front Microbiol 2020; 11:402. [PMID: 32218779 PMCID: PMC7079680 DOI: 10.3389/fmicb.2020.00402] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 02/26/2020] [Indexed: 11/13/2022] Open
Abstract
Acetogens are naturally capable of metabolizing carbon monoxide (CO), a component of synthesis gas (syngas), for autotrophic growth in order to produce biomass and metabolites such as acetyl-CoA via the Wood–Ljungdahl pathway. However, the autotrophic growth of acetogens is often inhibited by the presence of high CO concentrations because of CO toxicity, thus limiting their biosynthetic potential for industrial applications. Herein, we implemented adaptive laboratory evolution (ALE) for growth improvement of Eubacterium limosum ATCC 8486 under high CO conditions. The strain evolved under syngas conditions with 44% CO over 150 generations, resulting in a significant increased optical density (600 nm) and growth rate by 2.14 and 1.44 folds, respectively. In addition, the evolved populations were capable of proliferating under CO concentrations as high as 80%. These results suggest that cell growth is enhanced as beneficial mutations are selected and accumulated, and the metabolism is altered to facilitate the enhanced phenotype. To identify the causal mutations related to growth improvement under high CO concentrations, we performed whole genome resequencing of each population at 50-generation intervals. Interestingly, we found key mutations in CO dehydrogenase/acetyl-CoA synthase (CODH/ACS) complex coding genes, acsA and cooC. To characterize the mutational effects on growth under CO, we isolated single clones and confirmed that the growth rate and CO tolerance level of the single clone were comparable to those of the evolved populations and wild type strain under CO conditions. Furthermore, the evolved strain produced 1.34 folds target metabolite acetoin when compared to the parental strain while introducing the biosynthetic pathway coding genes to the strains. Consequently, this study demonstrates that the mutations in the CODH/ACS complex affect autotrophic growth enhancement in the presence of CO as well as the CO tolerance of E. limosum ATCC 8486.
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Affiliation(s)
- Seulgi Kang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Yoseb Song
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Sangrak Jin
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Jongoh Shin
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Jiyun Bae
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Dong Rip Kim
- Department of Mechanical Engineering, Hanyang University, Seoul, South Korea
| | - Jung-Kul Lee
- Department of Chemical Engineering, Konkuk University, Seoul, South Korea
| | - Sun Chang Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,Intelligent Synthetic Biology Center, Daejeon, South Korea
| | - Suhyung Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,Intelligent Synthetic Biology Center, Daejeon, South Korea
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35
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Litty D, Müller V. A Na + A 1 A O ATP synthase with a V-type c subunit in a mesophilic bacterium. FEBS J 2020; 287:3012-3023. [PMID: 31876375 DOI: 10.1111/febs.15193] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 11/18/2019] [Accepted: 12/22/2019] [Indexed: 01/01/2023]
Abstract
A1 AO ATP synthases with a V-type c subunit have only been found in hyperthermophilic archaea which makes bioenergetic analyses impossible due to the instability of liposomes at high temperatures. A search for a potential archaeal A1 AO ATP synthase with a V-type c subunit in a mesophilic organism revealed an A1 AO ATP synthase cluster in the anaerobic, acetogenic bacterium Eubacterium limosum KIST612. The enzyme was purified to apparent homogeneity from cells grown on methanol to a specific activity of 1.2 U·mg-1 with a yield of 12%. The enzyme contained subunits A, B, C, D, E, F, H, a, and c. Subunit c is predicted to be a typical V-type c subunit with only one ion (Na+ )-binding site. Indeed, ATP hydrolysis was strictly Na+ -dependent. N,N'-dicyclohexylcarbodiimide (DCCD) inhibited ATP hydrolysis, but inhibition was relieved by addition of Na+ . Na+ was shown directly to abolish binding of the fluorescence DCCD derivative, NCD-4, to subunit c, demonstrating a competition of Na+ and DCCD/NCD-4 for a common binding site. After incorporation of the A1 AO ATP synthase into liposomes, ATP-dependent primary transport of 22 Na+ as well as ΔµNa+ -driven ATP synthesis could be demonstrated. The Na+ A1 AO ATP synthase from E. limosum is the first ATP synthase with a V-type c subunit from a mesophilic organism. This will enable future bioenergetic analysis of these unique ATP synthases.
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Affiliation(s)
- Dennis Litty
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Frankfurt/Main, Germany
| | - Volker Müller
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Frankfurt/Main, Germany
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36
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Fukuyama Y, Inoue M, Omae K, Yoshida T, Sako Y. Anaerobic and hydrogenogenic carbon monoxide-oxidizing prokaryotes: Versatile microbial conversion of a toxic gas into an available energy. ADVANCES IN APPLIED MICROBIOLOGY 2020; 110:99-148. [PMID: 32386607 DOI: 10.1016/bs.aambs.2019.12.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Carbon monoxide (CO) is a gas that is toxic to various organisms including humans and even microbes; however, it has low redox potential, which can fuel certain microbes, namely, CO oxidizers. Hydrogenogenic CO oxidizers utilize an energy conservation system via a CO dehydrogenase/energy-converting hydrogenase complex to produce hydrogen gas, a zero emission fuel, by CO oxidation coupled with proton reduction. Biochemical and molecular biological studies using a few model organisms have revealed their enzymatic reactions and transcriptional response mechanisms using CO. Biotechnological studies for CO-dependent hydrogen production have also been carried out with these model organisms. In this chapter, we review recent advances in the studies of these microbes, which reveal their unique and versatile metabolic profiles and provides future perspectives on ecological roles and biotechnological applications. Over the past decade, the number of isolates has doubled (37 isolates in 5 phyla, 20 genera, and 32 species). Some of the recently isolated ones show broad specificity to electron acceptors. Moreover, accumulating genomic information predicts their unique physiologies and reveals their phylogenomic relationships with novel potential hydrogenogenic CO oxidizers. Combined with genomic database surveys, a molecular ecological study has unveiled the wide distribution and low abundance of these microbes. Finally, recent biotechnological applications of hydrogenogenic CO oxidizers have been achieved via diverse approaches (e.g., metabolic engineering and co-cultivation), and the identification of thermophilic facultative anaerobic CO oxidizers will promote industrial applications as oxygen-tolerant biocatalysts for efficient hydrogen production by genomic engineering.
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Affiliation(s)
- Yuto Fukuyama
- Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Masao Inoue
- Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Kimiho Omae
- Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Takashi Yoshida
- Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Yoshihiko Sako
- Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
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Deciphering mixotrophic Clostridium formicoaceticum metabolism and energy conservation: Genomic analysis and experimental studies. Genomics 2019; 111:1687-1694. [DOI: 10.1016/j.ygeno.2018.11.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 11/07/2018] [Accepted: 11/16/2018] [Indexed: 01/01/2023]
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Stegenta-Dąbrowska S, Drabczyński G, Sobieraj K, Koziel JA, Białowiec A. The Biotic and Abiotic Carbon Monoxide Formation During Aerobic Co-digestion of Dairy Cattle Manure With Green Waste and Sawdust. Front Bioeng Biotechnol 2019; 7:283. [PMID: 31737615 PMCID: PMC6828980 DOI: 10.3389/fbioe.2019.00283] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/04/2019] [Indexed: 11/24/2022] Open
Abstract
Carbon monoxide (CO), an air pollutant and a toxic gas to humans, can be generated during aerobic digestion of organic waste. CO is produced due to thermochemical processes, and also produced or consumed by cohorts of methanogenic, acetogenic, or sulfate-reducing bacteria. The exact mechanisms of biotic and abiotic formation of CO in aerobic digestion (particularly the effects of process temperature) are still not known. This study aimed to determine the temporal variation in CO concentrations during the aerobic digestion as a function of process temperature and activity of microorganisms. All experiments were conducted in controlled temperature reactors using homogeneous materials. The lab-scale tests with sterilized and non-sterilized mix of green waste, dairy cattle manure, sawdust (1:1:1 mass ratio) were carried out for 1 week at 10, 25, 30, 37, 40, 50, 60, 70°C to elucidate the biotic vs. abiotic effect. Gas concentrations of CO, O2, and CO2 inside the reactor were measured every 12 h. The CO concentrations observed for up to 30°C did not exceed 100 ppm v/v. For 50 and 60°C, significantly (p < 0.05) higher CO concentrations, reaching almost 600 ppm v/v, were observed. The regression analyses showed in both cases (sterile and non-sterile) a statistically significant effect (p < 0.05) of temperature on CO concentration, confirming that the increase in temperature causes an increase in CO concentration. The remaining factors (time, O2, and CO2 content) were not statistically significant (p > 0.05). A new polynomial model describing the effect of temperature, O2, and CO2 concentration on CO production during aerobic digestion of organic waste was formulated. It has been found that the proposed model for sterile variant had a better fit (R2 = 0.86) compared with non-sterile (R2 = 0.71). The model predicts CO emissions and could be considered for composting process optimization. The developed model could be further developed and useful for ambient air quality and occupational exposure to CO.
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Affiliation(s)
- Sylwia Stegenta-Dąbrowska
- Faculty of Life Sciences and Technology, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Grzegorz Drabczyński
- Faculty of Life Sciences and Technology, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Karolina Sobieraj
- Faculty of Life Sciences and Technology, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Jacek A Koziel
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, United States
| | - Andrzej Białowiec
- Faculty of Life Sciences and Technology, Wrocław University of Environmental and Life Sciences, Wrocław, Poland.,Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, United States
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Picking JW, Behrman EJ, Zhang L, Krzycki JA. MtpB, a member of the MttB superfamily from the human intestinal acetogen Eubacterium limosum, catalyzes proline betaine demethylation. J Biol Chem 2019; 294:13697-13707. [PMID: 31341018 DOI: 10.1074/jbc.ra119.009886] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/22/2019] [Indexed: 12/11/2022] Open
Abstract
The trimethylamine methyltransferase MttB is the founding member of a widely distributed superfamily of microbial proteins. Genes encoding most members of the MttB superfamily lack the codon for pyrrolysine that distinguishes previously characterized trimethylamine methyltransferases, leaving the function(s) of most of the enzymes in this superfamily unknown. Here, investigating the MttB family member MtpB from the human intestinal isolate Eubacterium limosum ATCC 8486, an acetogen that excretes N-methyl proline during growth on proline betaine, we demonstrate that MtpB catalyzes anoxic demethylation of proline betaine. MtpB along with MtqC (a corrinoid protein) and MtqA (a methylcorrinoid:tetrahydrofolate methyltransferase) was much more abundant in E. limosum cells grown on proline betaine than on lactate. We observed that recombinant MtpB methylates Co(I)-MtqC in the presence of proline betaine and that other quaternary amines are much less preferred substrates. MtpB, MtqC, and MtqA catalyze tetrahydrofolate methylation with proline betaine, thereby forming a key intermediate in the Wood-Ljungdahl acetogenesis pathway. To our knowledge, MtpB methylation of Co(I)-MtqC for the subsequent methylation of tetrahydrofolate represents the first described anoxic mechanism of proline betaine demethylation. The activities of MtpB and associated proteins in acetogens or other anaerobes provide a possible mechanism for the production of N-methyl proline by the gut microbiome. MtpB's activity characterized here strengthens the hypothesis that much of the MttB superfamily comprises quaternary amine-dependent methyltransferases.
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Affiliation(s)
- Jonathan W Picking
- Ohio State Biochemistry Program, Ohio State University, Columbus, Ohio 43210
| | - Edward J Behrman
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, Ohio 43210
| | - Liwen Zhang
- Campus Chemical Instrument Center Mass Spectrometry and Proteomics Facility, Ohio State University, Columbus, Ohio 43210
| | - Joseph A Krzycki
- Ohio State Biochemistry Program, Ohio State University, Columbus, Ohio 43210 .,Department of Microbiology, Ohio State University, Columbus, Ohio 43210
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Song Y, Shin J, Jin S, Lee JK, Kim DR, Kim SC, Cho S, Cho BK. Genome-scale analysis of syngas fermenting acetogenic bacteria reveals the translational regulation for its autotrophic growth. BMC Genomics 2018; 19:837. [PMID: 30470174 PMCID: PMC6260860 DOI: 10.1186/s12864-018-5238-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 11/09/2018] [Indexed: 11/11/2022] Open
Abstract
Background Acetogenic bacteria constitute promising biocatalysts for the conversion of CO2/H2 or synthesis gas (H2/CO/CO2) into biofuels and value-added biochemicals. These microorganisms are naturally capable of autotrophic growth via unique acetogenesis metabolism. Despite their biosynthetic potential for commercial applications, a systemic understanding of the transcriptional and translational regulation of the acetogenesis metabolism remains unclear. Results By integrating genome-scale transcriptomic and translatomic data, we explored the regulatory logic of the acetogenesis to convert CO2 into biomass and metabolites in Eubacterium limosum. The results indicate that majority of genes associated with autotrophic growth including the Wood-Ljungdahl pathway, the reduction of electron carriers, the energy conservation system, and gluconeogenesis were transcriptionally upregulated. The translation efficiency of genes in cellular respiration and electron bifurcation was also highly enhanced. In contrast, the transcriptionally abundant genes involved in the carbonyl branch of the Wood-Ljungdahl pathway, as well as the ion-translocating complex and ATP synthase complex in the energy conservation system, showed decreased translation efficiency. The translation efficiencies of genes were regulated by 5′UTR secondary structure under the autotrophic growth condition. Conclusions The results illustrated that the acetogenic bacteria reallocate protein synthesis, focusing more on the translation of genes for the generation of reduced electron carriers via electron bifurcation, rather than on those for carbon metabolism under autotrophic growth. Electronic supplementary material The online version of this article (10.1186/s12864-018-5238-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yoseb Song
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Jongoh Shin
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Sangrak Jin
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Jung-Kul Lee
- Department of Chemical Engineering, Konkuk University, Seoul, 05029, Republic of Korea
| | - Dong Rip Kim
- Department of Mechanical Engineering, Hanyang University, Seoul, 04763, Republic of Korea
| | - Sun Chang Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.,Intelligent Synthetic Biology Center, Daejeon, 34141, Republic of Korea
| | - Suhyung Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea. .,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea. .,Intelligent Synthetic Biology Center, Daejeon, 34141, Republic of Korea.
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Müller V, Chowdhury NP, Basen M. Electron Bifurcation: A Long-Hidden Energy-Coupling Mechanism. Annu Rev Microbiol 2018; 72:331-353. [PMID: 29924687 DOI: 10.1146/annurev-micro-090816-093440] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A decade ago, a novel mechanism to drive thermodynamically unfavorable redox reactions was discovered that is used in prokaryotes to drive endergonic electron transfer reactions by a direct coupling to an exergonic redox reaction in one soluble enzyme complex. This process is referred to as flavin-based electron bifurcation, or FBEB. An important function of FBEB is that it allows the generation of reduced low-potential ferredoxin (Fdred) from comparably high-potential electron donors such as NADH or molecular hydrogen (H2). Fdred is then the electron donor for anaerobic respiratory chains leading to the synthesis of ATP. In many metabolic scenarios, Fd is reduced by metabolic oxidoreductases and Fdred then drives endergonic metabolic reactions such as H2 production by the reverse, electron confurcation. FBEB is energetically more economical than ATP hydrolysis or reverse electron transport as a driving force for endergonic redox reactions; thus, it does "save" cellular ATP. It is essential for autotrophic growth at the origin of life and also allows for heterotrophic growth on certain low-energy substrates.
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Affiliation(s)
- Volker Müller
- Department of Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, 60438 Frankfurt, Germany;
| | - Nilanjan Pal Chowdhury
- Department of Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, 60438 Frankfurt, Germany;
| | - Mirko Basen
- Department of Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, 60438 Frankfurt, Germany;
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Buckel W, Thauer RK. Flavin-Based Electron Bifurcation, Ferredoxin, Flavodoxin, and Anaerobic Respiration With Protons (Ech) or NAD + (Rnf) as Electron Acceptors: A Historical Review. Front Microbiol 2018; 9:401. [PMID: 29593673 PMCID: PMC5861303 DOI: 10.3389/fmicb.2018.00401] [Citation(s) in RCA: 199] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 02/21/2018] [Indexed: 12/19/2022] Open
Abstract
Flavin-based electron bifurcation is a newly discovered mechanism, by which a hydride electron pair from NAD(P)H, coenzyme F420H2, H2, or formate is split by flavoproteins into one-electron with a more negative reduction potential and one with a more positive reduction potential than that of the electron pair. Via this mechanism microorganisms generate low- potential electrons for the reduction of ferredoxins (Fd) and flavodoxins (Fld). The first example was described in 2008 when it was found that the butyryl-CoA dehydrogenase-electron-transferring flavoprotein complex (Bcd-EtfAB) of Clostridium kluyveri couples the endergonic reduction of ferredoxin (E0′ = −420 mV) with NADH (−320 mV) to the exergonic reduction of crotonyl-CoA to butyryl-CoA (−10 mV) with NADH. The discovery was followed by the finding of an electron-bifurcating Fd- and NAD-dependent [FeFe]-hydrogenase (HydABC) in Thermotoga maritima (2009), Fd-dependent transhydrogenase (NfnAB) in various bacteria and archaea (2010), Fd- and H2-dependent heterodisulfide reductase (MvhADG-HdrABC) in methanogenic archaea (2011), Fd- and NADH-dependent caffeyl-CoA reductase (CarCDE) in Acetobacterium woodii (2013), Fd- and NAD-dependent formate dehydrogenase (HylABC-FdhF2) in Clostridium acidi-urici (2013), Fd- and NADP-dependent [FeFe]-hydrogenase (HytA-E) in Clostridium autoethanogrenum (2013), Fd(?)- and NADH-dependent methylene-tetrahydrofolate reductase (MetFV-HdrABC-MvhD) in Moorella thermoacetica (2014), Fd- and NAD-dependent lactate dehydrogenase (LctBCD) in A. woodii (2015), Fd- and F420H2-dependent heterodisulfide reductase (HdrA2B2C2) in Methanosarcina acetivorans (2017), and Fd- and NADH-dependent ubiquinol reductase (FixABCX) in Azotobacter vinelandii (2017). The electron-bifurcating flavoprotein complexes known to date fall into four groups that have evolved independently, namely those containing EtfAB (CarED, LctCB, FixBA) with bound FAD, a NuoF homolog (HydB, HytB, or HylB) harboring FMN, NfnB with bound FAD, or HdrA harboring FAD. All these flavoproteins are cytoplasmic except for the membrane-associated protein FixABCX. The organisms—in which they have been found—are strictly anaerobic microorganisms except for the aerobe A. vinelandii. The electron-bifurcating complexes are involved in a variety of processes such as butyric acid fermentation, methanogenesis, acetogenesis, anaerobic lactate oxidation, dissimilatory sulfate reduction, anaerobic- dearomatization, nitrogen fixation, and CO2 fixation. They contribute to energy conservation via the energy-converting ferredoxin: NAD+ reductase complex Rnf or the energy-converting ferredoxin-dependent hydrogenase complex Ech. This Review describes how this mechanism was discovered.
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Affiliation(s)
- Wolfgang Buckel
- Laboratory for Microbiology, Faculty of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - Rudolf K Thauer
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
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43
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Molecular basis of the flavin-based electron-bifurcating caffeyl-CoA reductase reaction. FEBS Lett 2018; 592:332-342. [DOI: 10.1002/1873-3468.12971] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 01/04/2018] [Accepted: 01/04/2018] [Indexed: 11/07/2022]
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Bengelsdorf FR, Beck MH, Erz C, Hoffmeister S, Karl MM, Riegler P, Wirth S, Poehlein A, Weuster-Botz D, Dürre P. Bacterial Anaerobic Synthesis Gas (Syngas) and CO 2+H 2 Fermentation. ADVANCES IN APPLIED MICROBIOLOGY 2018; 103:143-221. [PMID: 29914657 DOI: 10.1016/bs.aambs.2018.01.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Anaerobic bacterial gas fermentation gains broad interest in various scientific, social, and industrial fields. This microbial process is carried out by a specific group of bacterial strains called acetogens. All these strains employ the Wood-Ljungdahl pathway but they belong to different taxonomic groups. Here we provide an overview of the metabolism of acetogens and naturally occurring products. Characteristics of 61 strains were summarized and selected acetogens described in detail. Acetobacterium woodii, Clostridium ljungdahlii, and Moorella thermoacetica serve as model organisms. Results of approaches such as genome-scale modeling, proteomics, and transcriptomics are discussed. Metabolic engineering of acetogens can be used to expand the product portfolio to platform chemicals and to study different aspects of cell physiology. Moreover, the fermentation of gases requires specific reactor configurations and the development of the respective technology, which can be used for an industrial application. Even though the overall process will have a positive effect on climate, since waste and greenhouse gases could be converted into commodity chemicals, some legislative barriers exist, which hamper successful exploitation of this technology.
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Affiliation(s)
- Frank R Bengelsdorf
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany.
| | - Matthias H Beck
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Catarina Erz
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Sabrina Hoffmeister
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Michael M Karl
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Peter Riegler
- Technical University of Munich, Institute of Biochemical Engineering, Garching, Germany
| | - Steffen Wirth
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
| | - Anja Poehlein
- Genomic and Applied Microbiology & Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University, Göttingen, Germany
| | - Dirk Weuster-Botz
- Technical University of Munich, Institute of Biochemical Engineering, Garching, Germany
| | - Peter Dürre
- Institute of Microbiology and Biotechnology, University of Ulm, Ulm, Germany
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Park S, Yasin M, Jeong J, Cha M, Kang H, Jang N, Choi IG, Chang IS. Acetate-assisted increase of butyrate production by Eubacterium limosum KIST612 during carbon monoxide fermentation. BIORESOURCE TECHNOLOGY 2017; 245:560-566. [PMID: 28898856 DOI: 10.1016/j.biortech.2017.08.132] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 08/20/2017] [Accepted: 08/21/2017] [Indexed: 05/26/2023]
Abstract
The acetate-assisted cultivation of Eubacterium limosum KIST612 was found to provide a way for enhancing cell mass, the carbon monoxide (CO) consumption rate, and butyrate production using CO as an electron and energy source. Cell growth (146%), μmax (121%), and CO consumption rates (151%) increased significantly upon the addition of 30mM acetate to microbial cultures. The main product of CO fermentation by E. limosum KIST612 shifted from acetate to butyrate in the presence of acetate, and 5.72mM butyrate was produced at the end of the reaction. The resting cell experimental conditions indicated acetate uptake and an increase in the butyrate concentration. Three routes to acetate assimilation and energy conservation were suggested based on given experimental results and previously genome sequencing data. Acetate assimilation via propionate CoA-transferase (PCT) was expected to produce 1.5mol ATP/mol butyrate, and was thus anticipated to be the most preferred route.
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Affiliation(s)
- Shinyoung Park
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Muhammad Yasin
- Department of Chemical Engineering, COMSATS Institute of Information Technology (CIIT), Lahore, Pakistan
| | - Jiyeong Jeong
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Minseok Cha
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Hyunsoo Kang
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Nulee Jang
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea
| | - In-Geol Choi
- School of Life Sciences and Biotechnology, Korea University, 5 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - In Seop Chang
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 61005, Republic of Korea.
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46
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Overcoming the energetic limitations of syngas fermentation. Curr Opin Chem Biol 2017; 41:84-92. [DOI: 10.1016/j.cbpa.2017.10.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Revised: 09/28/2017] [Accepted: 10/03/2017] [Indexed: 01/05/2023]
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47
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Determination of the Genome and Primary Transcriptome of Syngas Fermenting Eubacterium limosum ATCC 8486. Sci Rep 2017; 7:13694. [PMID: 29057933 PMCID: PMC5651825 DOI: 10.1038/s41598-017-14123-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 10/03/2017] [Indexed: 01/05/2023] Open
Abstract
Autotrophic conversion of CO2 to value-added biochemicals has received considerable attention as a sustainable route to replace fossil fuels. Particularly, anaerobic acetogenic bacteria are naturally capable of reducing CO2 or CO to various metabolites. To fully utilize their biosynthetic potential, an understanding of acetogenesis-related genes and their regulatory elements is required. Here, we completed the genome sequence of the syngas fermenting Eubacterium limosum ATCC 8486 and determined its transcription start sites (TSS). We constructed a 4.4 Mb long circular genome with a GC content of 47.2% and 4,090 protein encoding genes. To understand the transcriptional and translational regulation, the primary transcriptome was augmented, identifying 1,458 TSSs containing a high pyrimidine (T/C) and purine nucleotide (A/G) content at the −1 and +1 position, respectively, along with 1,253 5′-untranslated regions, and principal promoter elements such as −10 (TATAAT) and −35 (TTGACA), and Shine-Dalgarno motifs (GGAGR). Further analysis revealed 93 non-coding RNAs, including one for potential transcriptional regulation of the hydrogenase complex via interaction with molybdenum or tungsten cofactors, which in turn controls formate dehydrogenase activity of the initial step of Wood-Ljungdahl pathway. Our results provide comprehensive genomic information for strain engineering to enhance the syngas fermenting capacity of acetogenic bacteria.
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De Tissera S, Köpke M, Simpson SD, Humphreys C, Minton NP, Dürre P. Syngas Biorefinery and Syngas Utilization. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2017. [DOI: 10.1007/10_2017_5] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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49
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Shin J, Song Y, Jeong Y, Cho BK. Analysis of the Core Genome and Pan-Genome of Autotrophic Acetogenic Bacteria. Front Microbiol 2016; 7:1531. [PMID: 27733845 PMCID: PMC5039349 DOI: 10.3389/fmicb.2016.01531] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 09/12/2016] [Indexed: 01/07/2023] Open
Abstract
Acetogens are obligate anaerobic bacteria capable of reducing carbon dioxide (CO2) to multicarbon compounds coupled to the oxidation of inorganic substrates, such as hydrogen (H2) or carbon monoxide (CO), via the Wood-Ljungdahl pathway. Owing to the metabolic capability of CO2 fixation, much attention has been focused on understanding the unique pathways associated with acetogens, particularly their metabolic coupling of CO2 fixation to energy conservation. Most known acetogens are phylogenetically and metabolically diverse bacteria present in 23 different bacterial genera. With the increased volume of available genome information, acetogenic bacterial genomes can be analyzed by comparative genome analysis. Even with the genetic diversity that exists among acetogens, the Wood-Ljungdahl pathway, a central metabolic pathway, and cofactor biosynthetic pathways are highly conserved for autotrophic growth. Additionally, comparative genome analysis revealed that most genes in the acetogen-specific core genome were associated with the Wood-Ljungdahl pathway. The conserved enzymes and those predicted as missing can provide insight into biological differences between acetogens and allow for the discovery of promising candidates for industrial applications.
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Affiliation(s)
- Jongoh Shin
- Systems and Synthetic Biology Laboratory, Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology Daejeon, South Korea
| | - Yoseb Song
- Systems and Synthetic Biology Laboratory, Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology Daejeon, South Korea
| | - Yujin Jeong
- Systems and Synthetic Biology Laboratory, Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and Technology Daejeon, South Korea
| | - Byung-Kwan Cho
- Systems and Synthetic Biology Laboratory, Department of Biological Sciences and KI for the BioCentury, Korea Advanced Institute of Science and TechnologyDaejeon, South Korea; Intelligent Synthetic Biology CenterDaejeon, South Korea
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Liew F, Martin ME, Tappel RC, Heijstra BD, Mihalcea C, Köpke M. Gas Fermentation-A Flexible Platform for Commercial Scale Production of Low-Carbon-Fuels and Chemicals from Waste and Renewable Feedstocks. Front Microbiol 2016; 7:694. [PMID: 27242719 PMCID: PMC4862988 DOI: 10.3389/fmicb.2016.00694] [Citation(s) in RCA: 206] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/26/2016] [Indexed: 12/13/2022] Open
Abstract
There is an immediate need to drastically reduce the emissions associated with global fossil fuel consumption in order to limit climate change. However, carbon-based materials, chemicals, and transportation fuels are predominantly made from fossil sources and currently there is no alternative source available to adequately displace them. Gas-fermenting microorganisms that fix carbon dioxide (CO2) and carbon monoxide (CO) can break this dependence as they are capable of converting gaseous carbon to fuels and chemicals. As such, the technology can utilize a wide range of feedstocks including gasified organic matter of any sort (e.g., municipal solid waste, industrial waste, biomass, and agricultural waste residues) or industrial off-gases (e.g., from steel mills or processing plants). Gas fermentation has matured to the point that large-scale production of ethanol from gas has been demonstrated by two companies. This review gives an overview of the gas fermentation process, focusing specifically on anaerobic acetogens. Applications of synthetic biology and coupling gas fermentation to additional processes are discussed in detail. Both of these strategies, demonstrated at bench-scale, have abundant potential to rapidly expand the commercial product spectrum of gas fermentation and further improve efficiencies and yields.
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