1
|
Pinela E, Schnürer A, Neubeck A, Moestedt J, Westerholm M. Impact of additives on syntrophic propionate and acetate enrichments under high-ammonia conditions. Appl Microbiol Biotechnol 2024; 108:433. [PMID: 39110235 PMCID: PMC11306274 DOI: 10.1007/s00253-024-13263-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 07/17/2024] [Accepted: 07/20/2024] [Indexed: 08/10/2024]
Abstract
High ammonia concentrations in anaerobic degradation systems cause volatile fatty acid accumulation and reduced methane yield, which often derive from restricted activity of syntrophic acid-oxidising bacteria and hydrogenotrophic methanogens. Inclusion of additives that facilitate the electron transfer or increase cell proximity of syntrophic species by flocculation can be a suitable strategy to counteract these problems, but its actual impact on syntrophic interactions has yet to be determined. In this study, microbial cultivation and molecular and microscopic analysis were performed to evaluate the impact of conductive (graphene, iron oxide) and non-conductive (zeolite) additives on the degradation rate of acetate and propionate to methane by highly enriched ammonia-tolerant syntrophic cultures derived from a biogas process. All additives had a low impact on the lag phase but resulted in a higher rate of acetate (except graphene) and propionate degradation. The syntrophic bacteria 'Candidatus Syntrophopropionicum ammoniitolerans', Syntrophaceticus schinkii and a novel hydrogenotrophic methanogen were found in higher relative abundance and higher gene copy numbers in flocculating communities than in planktonic communities in the cultures, indicating benefits to syntrophs of living in close proximity to their cooperating partner. Microscopy and element analysis showed precipitation of phosphates and biofilm formation in all batches except on the graphene batches, possibly enhancing the rate of acetate and propionate degradation. Overall, the concordance of responses observed in both acetate- and propionate-fed cultures highlight the suitability of the addition of iron oxide or zeolites to enhance acid conversion to methane in high-ammonia biogas processes. KEY POINTS: • All additives promoted acetate (except graphene) and propionate degradation. • A preference for floc formation by ammonia-tolerant syntrophs was revealed. • Microbes colonised the surfaces of iron oxide and zeolite, but not graphene.
Collapse
Affiliation(s)
- Eduardo Pinela
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden
| | - Anna Schnürer
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden
| | - Anna Neubeck
- Department of Earth Sciences, Uppsala University, 752 36, Uppsala, Sweden
| | - Jan Moestedt
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden
- Department of Biogas R & D, Tekniska Verken I Linköping AB (Publ.), Box 1500, 581 15, Linköping, Sweden
- Department of Thematic Studies - Environmental Change, Linköping University, 581 83, Linköping, Sweden
| | - Maria Westerholm
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden.
| |
Collapse
|
2
|
Prabhaharan D, Park H, Choi O, Abraham A, Sang BI. Enhancing cellulose acetate biodegradability in cigarette filters: an in-depth analysis of thermal alkaline pretreatment, microbial dynamics, and breakdown pathway prediction. Microb Cell Fact 2024; 23:199. [PMID: 39026314 PMCID: PMC11256436 DOI: 10.1186/s12934-024-02476-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 07/08/2024] [Indexed: 07/20/2024] Open
Abstract
BACKGROUND The demand for bioplastics has increased exponentially as they have emerged as alternatives to petrochemical plastics. However, there is a substantial lack of knowledge regarding bioplastic degradation. This study developed a novel pretreatment method to improve the accessibility of a bioplastic substrate for biodegradation. In this study, cellulose acetate, a bioplastic found in the world's most littered waste, e.g. cigarette filters, was selected as a potential substrate. Before anaerobic digestion, three thermal alkaline pretreatments: TA 30 °C, TA 90 °C, and TA 121 °C, were used to evaluate their effects on the chemical alterations of cellulose acetate. RESULT The ester groups in cellulose acetate were significantly reduced by the TA 30 °C pretreatment, as seen by a decrease in C = O stretching vibrations and shortening of C - O stretches (1,270 ∼ 1,210 cm- 1), indicating effective removal of acetyl groups. This pretreatment significantly enhanced cellulose acetate biodegradability to a maximum of 91%, surpassing the previously reported cellulose acetate degradation. Methane production increased to 695.0 ± 4 mL/g of volatile solid after TA 30 °C pretreatment, indicating enhanced cellulose acetate accessibility to microorganisms, which resulted in superior biogas production compared to the control (306.0 ± 10 mL/g of volatile solid). Diverse microbes in the anaerobic digestion system included hydrolytic (AB240379_g, Acetomicrobium, FN436103_g, etc.), fermentative, and volatile fatty acids degrading bacteria (JF417922_g, AB274492_g, Coprothermobacter, etc.), with Methanobacterium and Methanothermobacter being the sole hydrogenotrophic methanogens in the anaerobic digestion system. Additionally, an attempt to predict the pathway for the effective degradation of cellulose acetate from the microbial community in different pretreatment conditions. CONCLUSIONS To the best of our knowledge, this is the first study to estimate the maximum cellulose acetate degradation rate, with a simple and cost-effective pretreatment procedure. This approach holds promise for mitigating the environmental impact of cellulose acetate of cigarette filters and presents a sustainable and economically viable waste management strategy.
Collapse
Affiliation(s)
- Darsha Prabhaharan
- Department of Chemical Engineering, Hanyang University, 222 Wangsimniro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Hyojung Park
- Center of Convergence Bioceramic Materials, Korea Institute of Ceramic Engineering & Technology, 202, Osongsaengmyeong 1-ro, Osong-eup, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, Republic of Korea
| | - Okkyoung Choi
- Eco Lab Center, SK Ecoplant, 51, Jong-ro, Jongno-gu, Seoul, Republic of Korea
| | - Amith Abraham
- Department of Chemical Engineering, Hanyang University, 222 Wangsimniro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Byoung-In Sang
- Department of Chemical Engineering, Hanyang University, 222 Wangsimniro, Seongdong-gu, Seoul, 04763, Republic of Korea.
| |
Collapse
|
3
|
Li Y, Yin DM, Du XJ, Li HX, Zhang XY, Mahboubi A. Genome-centric metagenomics and methanogenic pathway analysis for acclimated anaerobic digestion of chicken manure with high ammonia stressed under thermophilic condition. ENVIRONMENTAL RESEARCH 2024; 258:119453. [PMID: 38909951 DOI: 10.1016/j.envres.2024.119453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 05/30/2024] [Accepted: 06/18/2024] [Indexed: 06/25/2024]
Abstract
Thermophilic anaerobic digestion (AD) of animal manure offers various environmental benefits but the process requires a microbial community acclimatized to high ammonia. In current study, a lab-scale continuous stirred tank reactor (CSTR) fed with chicken manure was operated under thermophilic condition for 450 days in total. Results showed that the volumetric methane production decreased from 445 to 328 and sharply declined to 153 mL L-1·d-1 with feeding total solid (TS) step increased from 5% to 7.5% and 10%, respectively. While, after a long-term stop feeding for 80 days, highly disturbed reactor was able to recover methane generation to 739 mL L-1·d-1 at feeding TS of 10%. Isotope analysis indicted acetate converted to methane through the syntrophic acetate oxidation and hydrogenotrophic methanogenesis (SAO-HM) pathway increased from 33% to 63% as the concentration of ammonium increased from 2493 to 6258 mg L-1. Significant different in the genome expression of the SAO bacterial from 0.09% to 1.23%, combining with main hydrogenotrophic partners (Methanoculleus spp. and Methanothermobacter spp.) contented of 2.1% and 99.9% during inhibitory and recovery stages, respectively. The highly expressed KEGG pathway in level 3 (enzyme genes) for the Recovery sludge combining with the extraordinary high abundance of genera Halocella sp. suggested that Halocella sp. might be a highly efficient hydrolytic and acidogenic microorganism and enhance the process of SAO during carbon metabolic flow to methane. This report will be a basis for further study of AD studies on high nitrogen content of poultry manure.
Collapse
Affiliation(s)
- Yan Li
- School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou, 213032, Jiangsu Province, China.
| | - Dong-Min Yin
- Institute of Urban and Rural Mining, Changzhou University, Changzhou, 213164, Jiangsu Province, China.
| | - Xiao-Jiao Du
- School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou, 213032, Jiangsu Province, China.
| | - Hao-Xuan Li
- School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou, 213032, Jiangsu Province, China.
| | - Xue-Ying Zhang
- School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou, 213032, Jiangsu Province, China.
| | - Amir Mahboubi
- Swedish Centre for Resource Recovery, University of Borås, Borås, SE-50190, Sweden.
| |
Collapse
|
4
|
Zeng Y, Zheng D, Li LP, Wang M, Gou M, Kamagata Y, Chen YT, Nobu MK, Tang YQ. Metabolism of novel potential syntrophic acetate-oxidizing bacteria in thermophilic methanogenic chemostats. Appl Environ Microbiol 2024; 90:e0109023. [PMID: 38259075 PMCID: PMC10880629 DOI: 10.1128/aem.01090-23] [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: 06/28/2023] [Accepted: 12/19/2023] [Indexed: 01/24/2024] Open
Abstract
Acetate is a major intermediate in the anaerobic digestion of organic waste to produce CH4. In methanogenic systems, acetate degradation is carried out by either acetoclastic methanogenesis or syntrophic degradation by acetate oxidizers and hydrogenotrophic methanogens. Due to challenges in the isolation of syntrophic acetate-oxidizing bacteria (SAOB), the diversity and metabolism of SAOB and the mechanisms of their interactions with methanogenic partners are not fully characterized. In this study, the in situ activity and metabolic characteristics of potential SAOB and their interactions with methanogens were elucidated through metagenomics and metatranscriptomics. In addition to the reported SAOB classified in the genera Tepidanaerobacter, Desulfotomaculum, and Thermodesulfovibrio, we identified a number of potential SAOB that are affiliated with Clostridia, Thermoanaerobacteraceae, Anaerolineae, and Gemmatimonadetes. The potential SAOB possessing the glycine-mediated acetate oxidation pathway dominates SAOB communities. Moreover, formate appeared to be the main product of the acetate degradation by the most active potential SAOB. We identified the methanogen partner of these potential SAOB in the acetate-fed chemostat as Methanosarcina thermophila. The dominated potential SAOB in each chemostat had similar metabolic characteristics, even though they were in different fatty-acid-fed chemostats. These novel syntrophic lineages are prevalent and may play critical roles in thermophilic methanogenic reactors. This study expands our understanding of the phylogenetic diversity and in situ biological functions of uncultured syntrophic acetate degraders and presents novel insights into how they interact with methanogens.IMPORTANCECombining reactor operation with omics provides insights into novel uncultured syntrophic acetate degraders and how they perform in thermophilic anaerobic digesters. This improves our understanding of syntrophic acetate degradation and contributes to the background knowledge necessary to better control and optimize anaerobic digestion processes.
Collapse
Affiliation(s)
- Yan Zeng
- Institute of New Energy and Low-carbon Technology, Sichuan University, Chengdu, Sichuan, China
| | - Dan Zheng
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China
| | - Lan-Peng Li
- Sinopec (Dalian) Research Institute of Petroleum and Petrochemicals Co. Ltd., Dalian, Liaoning, China
| | - Miaoxiao Wang
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China
| | - Min Gou
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China
| | - Yoichi Kamagata
- Graduate School of Agriculture, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Ya-Ting Chen
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China
| | - Masaru Konishi Nobu
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Kanagawa, Japan
| | - Yue-Qin Tang
- Institute of New Energy and Low-carbon Technology, Sichuan University, Chengdu, Sichuan, China
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China
- Engineering Research Centre of Alternative Energy Materials and Devices, Ministry of Education, Chengdu, Sichuan, China
- Sichuan Environmental Protection Key Laboratory of Organic Wastes Valorisation, Chengdu, Sichuan, China
| |
Collapse
|
5
|
McDaniel EA, Scarborough M, Mulat DG, Lin X, Sampara PS, Olson HM, Young RP, Eder EK, Attah IK, Markillie LM, Hoyt DW, Lipton MS, Hallam SJ, Ziels RM. Diverse electron carriers drive syntrophic interactions in an enriched anaerobic acetate-oxidizing consortium. THE ISME JOURNAL 2023; 17:2326-2339. [PMID: 37880541 PMCID: PMC10689502 DOI: 10.1038/s41396-023-01542-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 10/09/2023] [Accepted: 10/11/2023] [Indexed: 10/27/2023]
Abstract
In many anoxic environments, syntrophic acetate oxidation (SAO) is a key pathway mediating the conversion of acetate into methane through obligate cross-feeding interactions between SAO bacteria (SAOB) and methanogenic archaea. The SAO pathway is particularly important in engineered environments such as anaerobic digestion (AD) systems operating at thermophilic temperatures and/or with high ammonia. Despite the widespread importance of SAOB to the stability of the AD process, little is known about their in situ physiologies due to typically low biomass yields and resistance to isolation. Here, we performed a long-term (300-day) continuous enrichment of a thermophilic (55 °C) SAO community from a municipal AD system using acetate as the sole carbon source. Over 80% of the enriched bioreactor metagenome belonged to a three-member consortium, including an acetate-oxidizing bacterium affiliated with DTU068 encoding for carbon dioxide, hydrogen, and formate production, along with two methanogenic archaea affiliated with Methanothermobacter_A. Stable isotope probing was coupled with metaproteogenomics to quantify carbon flux into each community member during acetate conversion and inform metabolic reconstruction and genome-scale modeling. This effort revealed that the two Methanothermobacter_A species differed in their preferred electron donors, with one possessing the ability to grow on formate and the other only consuming hydrogen. A thermodynamic analysis suggested that the presence of the formate-consuming methanogen broadened the environmental conditions where ATP production from SAO was favorable. Collectively, these results highlight how flexibility in electron partitioning during SAO likely governs community structure and fitness through thermodynamic-driven mutualism, shedding valuable insights into the metabolic underpinnings of this key functional group within methanogenic ecosystems.
Collapse
Affiliation(s)
- Elizabeth A McDaniel
- Department of Civil Engineering, The University of British Columbia, Vancouver, BC, Canada
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
| | - Matthew Scarborough
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, VT, USA
| | - Daniel Girma Mulat
- Department of Civil Engineering, The University of British Columbia, Vancouver, BC, Canada
| | - Xuan Lin
- Department of Civil Engineering, The University of British Columbia, Vancouver, BC, Canada
| | - Pranav S Sampara
- Department of Civil Engineering, The University of British Columbia, Vancouver, BC, Canada
| | - Heather M Olson
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Robert P Young
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Elizabeth K Eder
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Isaac K Attah
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Lye Meng Markillie
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - David W Hoyt
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Mary S Lipton
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Steven J Hallam
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
- ECOSCOPE Training Program, The University of British Columbia, Vancouver, BC, Canada
- Graduate Program in Bioinformatics, The University of British Columbia, Vancouver, BC, Canada
- Genome Science and Technology Program, The University of British Columbia, Vancouver, BC, Canada
- Life Sciences Institute, The University of British Columbia, Vancouver, BC, Canada
| | - Ryan M Ziels
- Department of Civil Engineering, The University of British Columbia, Vancouver, BC, Canada.
- Genome Science and Technology Program, The University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
6
|
Li X, Yu Z, Ge X, Zhang W, Fang Y, Liu W, Wang A. Volatile fatty acids bio-production using extracellular polymeric substances disengaged from sludge for carbon source recycling. BIORESOURCE TECHNOLOGY 2023; 386:129565. [PMID: 37506926 DOI: 10.1016/j.biortech.2023.129565] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 07/19/2023] [Accepted: 07/25/2023] [Indexed: 07/30/2023]
Abstract
Excessive waste-activated sludge (WAS) and insufficient carbon source (CS) for biological nitrogen removal (BNR) often coexist in municipal sewage treatment. Although the production of volatile fatty acids (VFAs) from WAS has been recognized as a promising solution, the development is limited by low VFAs production efficiency and dewatering deterioration of sludge. This study extracted the extracellular polymeric substances (EPS) from sludge by low-temperature thermal-hydrolysis (LTH) and high-speed hydro-cyclone (HSHC) pretreatment and recovered it for high-quality VFAs bio-production in thermophilic fermentation. Microbial mechanism analysis disclosed that interspecific interaction networks composed of functional flora, which accumulate VFAs by bio-converting EPS primarily and supplemented by EPS synthesis, guaranteed the efficient bio-production of VFAs. This process scheme shows promise in providing alternative denitrification CSs and avoiding deterioration of sludge dewaterability.
Collapse
Affiliation(s)
- Xiqi Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Zhe Yu
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Xiaoli Ge
- Tianjin Municipal Engineering Design & Research Institute Co. Ltd., Tianjin 300000, China
| | - Wenzhe Zhang
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yingke Fang
- School of Ecology and Environment, Zhengzhou University, Zhengzhou 450002, China
| | - Wenzong Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
| | - Aijie Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China; CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| |
Collapse
|
7
|
Zhuravleva E, Kovalev A, Kovalev D, Kotova I, Shekhurdina S, Laikova A, Krasnovsky A, Pygamov T, Vivekanand V, Li L, He C, Litti Y. Does carbon cloth really improve thermophilic anaerobic digestion performance on a larger scale? focusing on statistical analysis and microbial community dynamics. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 341:118124. [PMID: 37172349 DOI: 10.1016/j.jenvman.2023.118124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 05/03/2023] [Accepted: 05/06/2023] [Indexed: 05/14/2023]
Abstract
Currently, the phenomenon of direct interspecies electron transfer (DIET) is of great interest in the technology of anaerobic digestion (AD) due to potential performance benefits. However, the conditions for the occurrence of DIET and its limits on improving AD under conditions close to real have not been studied enough. This research is concentrated on the effect of conductive carbon cloth (R3), in comparison with a dielectric fiberglass cloth (R2) and control (R1), on the AD performance in large (90 L) thermophilic reactors, fed with a mixture of simulated organic fraction of municipal solid waste and sewage sludge. While organic loading rate (OLR) was gradually increased from 2.4 to 8.66 kg VS/(m3 day), a statistically significant (p < 0.05) difference in biogas production was observed between R1 and both R2 and R3. However, at a maximum OLR of 12.12 kg VS/(m3 day) in R3, an increase in biogas production (p < 0.05) was observed both compared to R1 (by 8.97%) and R2 (by 4.24%). The content of volatile fatty acids in R3 as a whole was the lowest, especially at the maximum OLR. Biofilm on carbon cloth was rich in syntrophic microorganisms of the genera Tepidanaerobacter, as well as Defluviitoga, capable of DIET in mixed cultures with Methanothrix, which was the most abundant methanogen in biofilm. Suspended Bifidobacterium, Fervidobacterium and Anaerobaculum were negatively affected, while Defluviitoga, Methanothermobacter and Methanosarcina, on the contrary, were positively affected by the increase in OLR and showed, respectively, a negative and positive correlation (p < 0.05) with the main AD performance parameters.
Collapse
Affiliation(s)
- Elena Zhuravleva
- Federal Research Center "Fundamentals of Biotechnology" of the Russian Academy of Sciences; Moscow, Leninsky Prospekt, 33, 2, 119071, Russia; Department of Biology, Lomonosov Moscow State University; Moscow, Leninskie Gory, 1, 12, 119899, Russia.
| | - Andrey Kovalev
- Federal State Budgetary Scientific Institution "Federal Scientific Agroengineering Center VIM"; Moscow, 1st Institutskiy Proezd, 5, 109428, Russia.
| | - Dmitriy Kovalev
- Federal State Budgetary Scientific Institution "Federal Scientific Agroengineering Center VIM"; Moscow, 1st Institutskiy Proezd, 5, 109428, Russia.
| | - Irina Kotova
- Department of Biology, Lomonosov Moscow State University; Moscow, Leninskie Gory, 1, 12, 119899, Russia.
| | - Svetlana Shekhurdina
- Federal Research Center "Fundamentals of Biotechnology" of the Russian Academy of Sciences; Moscow, Leninsky Prospekt, 33, 2, 119071, Russia; Department of Biology, Lomonosov Moscow State University; Moscow, Leninskie Gory, 1, 12, 119899, Russia.
| | - Aleksandra Laikova
- Federal Research Center "Fundamentals of Biotechnology" of the Russian Academy of Sciences; Moscow, Leninsky Prospekt, 33, 2, 119071, Russia; Department of Biology, Lomonosov Moscow State University; Moscow, Leninskie Gory, 1, 12, 119899, Russia.
| | - Anatoly Krasnovsky
- National Research Tomsk State University, Tomsk, Lenin Ave., 36, 634050, Russia.
| | - Timur Pygamov
- Gubkin University, Moscow, Leninsky Prospekt, 65, 119991, Russia.
| | - Vivekanand Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, Jaipur, 302017, Rajasthan, India.
| | - Lianhua Li
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, 510640, China.
| | - Chao He
- Key Laboratory of New Materials and Facilities for Rural Renewable Energy of China's Ministry of Agriculture and Rural Affairs, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Yuriy Litti
- Federal Research Center "Fundamentals of Biotechnology" of the Russian Academy of Sciences; Moscow, Leninsky Prospekt, 33, 2, 119071, Russia.
| |
Collapse
|
8
|
Moon J, Schubert A, Waschinger LM, Müller V. Reprogramming the metabolism of an acetogenic bacterium to homoformatogenesis. THE ISME JOURNAL 2023:10.1038/s41396-023-01411-2. [PMID: 37061584 DOI: 10.1038/s41396-023-01411-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/30/2023] [Accepted: 04/04/2023] [Indexed: 04/17/2023]
Abstract
Methyl groups are abundant in anoxic environments and their utilization as carbon and energy sources by microorganisms involves oxidation of the methyl groups to CO2, followed by transfer of the electrons to an acceptor. In acetogenic bacteria, the electron acceptor is CO2 that is reduced to enzyme bound carbon monoxide, the precursor of the carboxyl group in acetate. Here, we describe the generation of a mutant of the acetogen Acetobacterium woodii in which the last step in methyl group oxidation, formate oxidation to CO2 catalyzed by the HDCR enzyme, has been genetically deleted. The mutant grew on glycine betaine as methyl group donor, and in contrast to the wild type, formed formate alongside acetate, in a 1:2 ratio, demonstrating that methyl group oxidation stopped at the level of formate and reduced electron carriers were reoxidized by CO2 reduction to acetate. In the presence of the alternative electron acceptor caffeate, CO2 was no longer reduced to acetate, formate was the only product and all the carbon went to formate. Apparently, acetogenesis was not required to sustain formatogenic growth. This is the first demonstration of a genetic reprogramming of an acetogen into a formatogen that grows by homoformatogenesis from methyl groups. Formate production from methyl groups is not only of biotechnological interest but also for the mechanism of electron transfer in syntrophic interactions in anoxic environments.
Collapse
Affiliation(s)
- Jimyung Moon
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, D-60438, Frankfurt, Germany
| | - Anja Schubert
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, D-60438, Frankfurt, Germany
| | - Lara M Waschinger
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, D-60438, Frankfurt, Germany
| | - Volker Müller
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, D-60438, Frankfurt, Germany.
| |
Collapse
|
9
|
Prem EM, Schwarzenberger A, Markt R, Wagner AO. Effects of phenyl acids on different degradation phases during thermophilic anaerobic digestion. Front Microbiol 2023; 14:1087043. [PMID: 37089573 PMCID: PMC10113666 DOI: 10.3389/fmicb.2023.1087043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 03/06/2023] [Indexed: 04/08/2023] Open
Abstract
Aromatic compounds like phenyl acids (PA) can accumulate during anaerobic digestion (AD) of organic wastes due to an increased entry of lignocellulose, secondary plant metabolites or proteins, and thermodynamic challenges in degrading the benzene ring. The effects of aromatic compounds can be various – from being highly toxic to be stimulating for methanogenesis – depending on many parameters like inoculum or molecular characteristics of the aromatic compound. To contribute to a better understanding of the consequences of PA exposure during AD, the aim was to evaluate the effects of 10 mM PA on microbial communities degrading different, degradation phase–specific substrates in thermophilic batch reactors within 28 days: Microcrystalline cellulose (MCC, promoting hydrolytic to methanogenic microorganisms), butyrate or propionate (promoting syntrophic volatile fatty acid (VFA) oxidisers to methanogens), or acetate (promoting syntrophic acetate oxidisers to methanogens). Methane production, VFA concentrations and pH were evaluated, and microbial communities and extracellular polymeric substances (EPS) were assessed. The toxicity of PA depended on the type of substrate which in turn determined the (i) microbial diversity and composition and (ii) EPS quantity and quality. Compared with the respective controls, methane production in MCC reactors was less impaired by PA than in butyrate, propionate and acetate reactors which showed reductions in methane production of up to 93%. In contrast to the controls, acetate concentrations were high in all PA reactors at the end of incubation thus acetate was a bottle-neck intermediate in those reactors. Considerable differences in EPS quantity and quality could be found among substrates but not among PA variants of each substrate. Methanosarcina spp. was the dominant methanogen in VFA reactors without PA exposure and was inhibited when PA were present. VFA oxidisers and Methanothermobacter spp. were abundant in VFA assays with PA exposure as well as in all MCC reactors. As MCC assays showed higher methane yields, a higher microbial diversity and a higher EPS quantity and quality than VFA reactors when exposed to PA, we conclude that EPS in MCC reactors might have been beneficial for absorbing/neutralising phenyl acids and keeping (more susceptible) microorganisms shielded in granules or biofilms.
Collapse
Affiliation(s)
- Eva Maria Prem
- Department of Microbiology, Universität Innsbruck, Innsbruck, Austria
| | | | - Rudolf Markt
- Department of Microbiology, Universität Innsbruck, Innsbruck, Austria
| | | |
Collapse
|
10
|
Feng G, Zeng Y, Wang HZ, Chen YT, Tang YQ. Proteiniphilum and Methanothrix harundinacea became dominant acetate utilizers in a methanogenic reactor operated under strong ammonia stress. Front Microbiol 2023; 13:1098814. [PMID: 36687577 PMCID: PMC9853277 DOI: 10.3389/fmicb.2022.1098814] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 12/15/2022] [Indexed: 01/09/2023] Open
Abstract
Microorganisms in anaerobic digestion (AD) are easily affected by ammonia, especially acetoclastic methanogens. Thus, in ammonia-suppressed AD systems, acetate degradation is reported to be carried out mainly by the cooperation of syntrophic acetate oxidizers and hydrogenotrophic methanogens. Previous studies have revealed ammonia inhibition on microbial flora by AD performance, but the effect mechanism of ammonia on microbial metabolism remains poorly understood. In this study, we constructed a mesophilic chemostat fed with acetate as the sole carbon source, gradually increased the total ammonia nitrogen (TAN) concentration from 1 g L-1 to 6 g L-1, and employed the 16S rRNA gene, metagenomics, and metatranscriptomics analysis to characterize the microbial community structure and metabolic behavior. The results showed that even at the TAN of 6 g L-1 (pH 7.5), the methanogenesis kept normal, the biogas production was approximately 92% of that at TAN of 1 g L-1 and the acetate degradation ratio reached 99%, suggesting the strong TAN tolerance of the microbial community enriched. 16S rRNA gene analysis suggested that the microbial community structure changed along with the TAN concentration. Methanothrix predominated in methanogens all the time, in which the dominant species was gradually replaced from M. soehngenii to M. harundinacea with the increased TAN. Dominant bacterial species also changed and Proteiniphilum showed a significant positive correlation with increased TAN. Meta-omics analysis showed that the absolute dominant microorganisms at TAN of 6 g L-1 were M. harundinacea and Proteiniphilum, both of which highly expressed genes for anti-oxidative stress. M. harundinacea and the second dominant methanogen Methanosarcina highly expressed both acetate cleavage and CO2 reduction pathways, suggesting the possibility that these two pathways contributed to methanogenesis together. Proteiniphilum and some other species in Firmicutes and Synergistetes were likely acetate oxidizers in the community as they highly expressed genes for syntrophic acetate oxidization, H2 generation, and electron transfer. These results suggested that Proteiniphilum as well as M. harundinacea have strong ammonia tolerance and played critical roles in acetate degradation under ammonia-suppressed conditions. The achievements of the study would contribute to the regulation and management of the AD process.
Collapse
Affiliation(s)
- Gao Feng
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China
| | - Yan Zeng
- Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu, Sichuan, China
| | - Hui-Zhong Wang
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China
| | - Ya-Ting Chen
- Institute for Disaster Management and Reconstruction, Sichuan University, Chengdu, Sichuan, China
| | - Yue-Qin Tang
- College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China,Sichuan Environmental Protection Key Laboratory of Organic Wastes Valorization, Chengdu, Sichuan, China,Engineering Research Center of Alternative Energy Materials & Devices, Ministry of Education, Chengdu, Sichuan, China,*Correspondence: Yue-Qin Tang,
| |
Collapse
|
11
|
Li C, Hao L, Lü F, Duan H, Zhang H, He P. Syntrophic Acetate-Oxidizing Microbial Consortia Enriched from Full-Scale Mesophilic Food Waste Anaerobic Digesters Showing High Biodiversity and Functional Redundancy. mSystems 2022; 7:e0033922. [PMID: 36073802 PMCID: PMC9600251 DOI: 10.1128/msystems.00339-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 08/15/2022] [Indexed: 12/24/2022] Open
Abstract
Syntrophic acetate oxidation (SAO) coupled with hydrogenotrophic methanogenesis (HM) plays a vital role in the anaerobic digestion of protein-rich feedstocks such as food wastes. However, current knowledge of the biodiversity and genetic potential of the involved microbial participants, especially syntrophic acetate-oxidizing bacteria (SAOB), is limited due to the low abundance of these microorganisms and challenges in their isolation. The intent of this study was to enrich and identify potential SAOB. Therefore, we conducted continuous acetate feeding under high ammonia concentrations using two separate inoculum consortia of microorganisms that originated from full-scale mesophilic food waste digesters, which lasted for more than 200 days. Using 16S rRNA gene amplicon and metagenomic analyses, we observed a convergence of the experimental microbial communities during the enrichment regarding taxonomic composition and metabolic functional composition. Stable carbon isotope analyses of biogas indicated that SAO-HM was the dominant methanogenic pathway during the enrichment process. The hydrogenotrophic methanogen Methanoculleus dominated the archaeal community. The enriched SAO community featured high biodiversity and metabolic functional redundancy. By analyzing the metagenome-assembled genomes, the known SAOB Syntrophaceticus schinkii and six uncultured populations were identified to have the genetic potential to perform SAO through the conventional reversed Wood-Ljungdahl pathway, while another six bacteria were found to encode the reversed Wood-Ljungdahl pathway combined with a glycine cleavage system as novel SAOB candidates. These results showed that the food waste anaerobic digesters harbor diverse SAOB and highlighted the importance of the glycine cleavage system for acetate oxidation. IMPORTANCE Syntrophic acetate oxidation to CO2 and H2, together with hydrogenotrophic methanogenesis, contributes to much of the carbon flux in the anaerobic digestion of organic wastes, especially at high ammonia concentrations. A deep understanding of the biodiversity, metabolic genetic potential, and ecology of the SAO community can help to improve biomethane production from wastes for clean energy production. Here, we enriched the SAO-HM functional guild obtained from full-scale food waste anaerobic digesters and recorded dynamic changes in community taxonomic composition and functional profiles. By reconstructing the metabolic pathways, diverse known and novel bacterial members were found to have SAO potential via the reversed Wood-Ljungdahl (WL) pathway alone, or via the reversed WL pathway with a glycine cleavage system (WLP-GCS), and those catalyzing WLP-GCS showed higher microbial abundance. This study revealed the biodiversity and metabolic functional redundancy of SAOB in full-scale anaerobic digester systems and provided inspiration for further genome-centric studies.
Collapse
Affiliation(s)
- Chao Li
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
| | - Liping Hao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, People’s Republic of China
| | - Fan Lü
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, People’s Republic of China
| | - Haowen Duan
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
| | - Hua Zhang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, People’s Republic of China
| | - Pinjing He
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
| |
Collapse
|
12
|
Zhang L, Gong X, Chen Z, Zhou Y. Genome-centric metagenomics analysis revealed the metabolic function of abundant microbial communities in thermal hydrolysis-assisted thermophilic anaerobic digesters under propionate stress. BIORESOURCE TECHNOLOGY 2022; 360:127574. [PMID: 35792328 DOI: 10.1016/j.biortech.2022.127574] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/29/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
The ecological roles of microbial communities and how they interact with each other in thermal hydrolysis process (THP) assisted thermophilic anaerobic digestion (THP-AD) reactors remain largely unknown, especially under propionate stress. Two thermophilic THP-AD reactors had methane yield of 240-248 mL/g VSadded, but accumulated approximately 2000 mg/L propionate. Genome-centric metagenomics analysis showed that 68 metagenome-assembled genomes (MAGs) were recovered, 32 MAGs of which were substantially enriched. Firmicutes spp. dominated the enriched microbial community, including hydrolytic/fermentative bacteria and syntrophs. Methanogenic activities were mainly mediated by Methanosarcina sp. and Methanothermobacter spp. In addition to hydrogenotrophic methanogens, Thermodesulfovibrio sp. could also be a vital H2 scavenger, contributing to maintaining low H2 partial pressure in the bioreactors. The remarkable accumulation of propionate could be likely attributed to the weak syntrophic propionate-oxidizing activity or its absence. These findings advanced our knowledge about the mutualistic symbiosis of carbon metabolism in thermophilic THP-AD reactors.
Collapse
Affiliation(s)
- Liang Zhang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Xianzhe Gong
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Zhiyi Chen
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China; State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| |
Collapse
|
13
|
Rossi A, Morlino MS, Gaspari M, Basile A, Kougias P, Treu L, Campanaro S. Analysis of the anaerobic digestion metagenome under environmental stresses stimulating prophage induction. MICROBIOME 2022; 10:125. [PMID: 35965344 PMCID: PMC9377139 DOI: 10.1186/s40168-022-01316-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 06/25/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND The viral community has the potential to influence the structure of the microbiome and thus the yield of the anaerobic digestion process. However, the virome composition in anaerobic digestion is still under-investigated. A viral induction experiment was conducted on separate batches undergoing a series of DNA-damaging stresses, in order to coerce temperate viruses to enter the lytic cycle. RESULTS The sequencing of the metagenome revealed a viral community almost entirely composed of tailed bacteriophages of the order Caudovirales. Following a binning procedure 1,092 viral and 120 prokaryotic genomes were reconstructed, 64 of which included an integrated prophage in their sequence. Clustering of coverage profiles revealed the presence of species, both viral and microbial, sharing similar reactions to shocks. A group of viral genomes, which increase under organic overload and decrease under basic pH, uniquely encode the yopX gene, which is involved in the induction of temperate prophages. Moreover, the in-silico functional analysis revealed an enrichment of sialidases in viral genomes. These genes are associated with tail proteins and, as such, are hypothesised to be involved in the interaction with the host. Archaea registered the most pronounced changes in relation to shocks and featured behaviours not shared with other species. Subsequently, data from 123 different samples of the global anaerobic digestion database was used to determine coverage profiles of host and viral genomes on a broader scale. CONCLUSIONS Viruses are key components in anaerobic digestion environments, shaping the microbial guilds which drive the methanogenesis process. In turn, environmental conditions are pivotal in shaping the viral community and the rate of induction of temperate viruses. This study provides an initial insight into the complexity of the anaerobic digestion virome and its relation with the microbial community and the diverse environmental parameters. Video Abstract.
Collapse
Affiliation(s)
- Alessandro Rossi
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131, Padova, Italy
| | - Maria Silvia Morlino
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131, Padova, Italy
| | - Maria Gaspari
- Department of Hydraulics, Soil Science and Agricultural Engineering, Faculty of Agriculture, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - Arianna Basile
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131, Padova, Italy
| | - Panagiotis Kougias
- Soil and Water Resources Institute, Hellenic Agricultural Organisation Demeter, Thermi, 57001, Thessaloniki, Greece
| | - Laura Treu
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131, Padova, Italy.
| | - Stefano Campanaro
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131, Padova, Italy
- CRIBI biotechnology center, University of Padua, via U. Bassi 58/b, 35131, Padova, Italy
| |
Collapse
|
14
|
Li MT, Rao L, Wang L, Gou M, Sun ZY, Xia ZY, Song WF, Tang YQ. Bioaugmentation with syntrophic volatile fatty acids-oxidizing consortia to alleviate the ammonia inhibition in continuously anaerobic digestion of municipal sludge. CHEMOSPHERE 2022; 288:132389. [PMID: 34606893 DOI: 10.1016/j.chemosphere.2021.132389] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/07/2021] [Accepted: 09/26/2021] [Indexed: 05/23/2023]
Abstract
Ammonia inhibition easily affects the performance of anaerobic digestion (AD) for municipal sludge and the oxidization of volatile fatty acids (VFAs) is the rate-limiting step of this process. Bioaugmentation is considered to be an effective method to alleviate ammonia inhibition of AD, but most study used the hydrogenotrophic methanogens as the bioaugmentation culture. In this study, bioaugmentation of mesophilic AD (MAD) and thermophilic AD (TAD) under ammonia inhibition with syntrophic acetate and propionate oxidizing consortia was investigated. The results showed that the bioaugmented reactors recovered earlier than control reactors with 20 (MAD) and 8 (TAD) days, respectively. The high-throughput 16S rRNA gene sequencing indicated that the relative abundance of carbohydrates fermenter (Lentimicrobium), syntrophic VFAs-oxidizing bacteria (Rikenellaceae_DMER64, Smithella and Syntrophobacter) and acetoclastic and hydrogenotrophic methanogens (Methanosaeta, Methanolinea and Methanospirillum) increased in MAD after bioaugmentation. However, part of the bioaugmentation culture could not adapt to the high free ammonia (FAN) concentration in MAD and the effect was weakened. In TAD, proteolytic bacteria (Keratinibaculum and Tepidimicrobium), syntrophic VFAs-oxidizing bacteria (Syntrophomonas) and hydrogenotrophic methanogen (Methanosarcina) were strengthened. The effect of bioaugmentation in TAD was durable even at higher organic loading rate (OLR), due to its positive influence on microbial community. These results suggested that the different bioaugmentation mechanism occurred in MAD and TAD, which are derived from the synergetic effects of ammonia tolerance and microbial interactions. Our study revealed the VFAs-oxidizing consortia as bioaugmented culture could be the potential strategy to alleviate the ammonia stress of AD.
Collapse
Affiliation(s)
- Mao-Ting Li
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan, 610065, China
| | - Ling Rao
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan, 610065, China
| | - Lu Wang
- State Key Laboratory of Enhanced Oil Recovery, Research Institute of Petroleum Exploration and Development, CNPC, Beijing, 100083, PR China
| | - Min Gou
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan, 610065, China.
| | - Zhao-Yong Sun
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan, 610065, China
| | - Zi-Yuan Xia
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan, 610065, China
| | - Wen-Feng Song
- Research Institute of Petroleum Exploration and Development, CNPC, Beijing, 100083, PR China
| | - Yue-Qin Tang
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan, 610065, China
| |
Collapse
|
15
|
Hardy J, Bonin P, Lazuka A, Gonidec E, Guasco S, Valette C, Lacroix S, Cabrol L. Similar Methanogenic Shift but Divergent Syntrophic Partners in Anaerobic Digesters Exposed to Direct versus Successive Ammonium Additions. Microbiol Spectr 2021; 9:e0080521. [PMID: 34612672 PMCID: PMC8510171 DOI: 10.1128/spectrum.00805-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/02/2021] [Indexed: 01/04/2023] Open
Abstract
During anaerobic digestion (AD) of protein-rich wastewater, ammonium (NH4+) is released by amino acid degradation. High NH4+ concentrations disturb the AD microbiome balance, leading to process impairments. The sensitivity of the AD microbiome to NH4+ and the inhibition threshold depend on multiple parameters, especially the previous microbial acclimation to ammonium stress. However, little is known about the effect of different NH4+ acclimation strategies on the differential expression of key active microbial taxa. Here, we applied NH4+ inputs of increasing intensity (from 1.7 to 15.2 g N-NH4+ liters-1) in batch assays fed with synthetic wastewater, according to two different strategies: (i) direct independent inputs at a unique target concentration and (ii) successive inputs in a stepwise manner. In both strategies, along the NH4+ gradient, the active methanogens shifted from acetoclastic Methanosaeta to Methanosarcina and eventually hydrogenotrophic Methanoculleus. Despite shorter latency times, the successive input modality led to lower methane production rate, lower soluble chemical oxygen demand (sCOD) removal efficiency, and lower half maximal inhibitory concentration, together with higher volatile fatty acid (VFA) accumulation, compared to the independent input modality. These differential performances were associated with a drastically distinct succession pattern of the active bacterial partners in both experiments. In particular, the direct exposure modality was characterized by a progressive enrichment of VFA producers (mainly Tepidimicrobium) and syntrophic VFA oxidizers (mainly Syntrophaceticus) with increasing NH4+ concentration, while the successive exposure modality was characterized by a more dynamic succession of VFA producers (mainly Clostridium, Sporanaerobacter, Terrisporobacter) and syntrophic VFA oxidizers (mainly Tepidanaerobacter, Syntrophomonas). These results bring relevant insights for improved process management through inoculum adaptation, bioaugmentation, or community-driven optimization. IMPORTANCE Anaerobic digestion (AD) is an attractive biotechnological process for wastewater bioremediation and bioenergy production in the form of methane-rich biogas. However, AD can be inhibited by ammonium generated by protein-rich effluent, commonly found in agro-industrial activities. Insights in the microbial community composition and identification of AD key players are crucial for anticipating process impairments in response to ammonium stress. They can also help in defining an optimal microbiome adapted to high ammonium levels. Here, we compared two strategies for acclimation of AD microbiome to increasing ammonium concentration to better understand the effect of this stress on the methanogens and their bacterial partners. Our results suggest that long-term cumulative exposure to ammonia disrupted the AD microbiome more strongly than direct (independent) ammonium additions. We identified bioindicators with different NH4+ tolerance capacity among VFA producers and syntrophic VFA oxidizers.
Collapse
Affiliation(s)
- Julie Hardy
- MIO, Aix Marseille University, University of Toulon, CNRS, IRD, Marseille, France
- Scientific & Technological Expertise Department, Veolia, Maisons-Laffitte, France
| | - Patricia Bonin
- MIO, Aix Marseille University, University of Toulon, CNRS, IRD, Marseille, France
| | - Adele Lazuka
- Scientific & Technological Expertise Department, Veolia, Maisons-Laffitte, France
| | - Estelle Gonidec
- Scientific & Technological Expertise Department, Veolia, Maisons-Laffitte, France
| | - Sophie Guasco
- MIO, Aix Marseille University, University of Toulon, CNRS, IRD, Marseille, France
| | - Corinne Valette
- MIO, Aix Marseille University, University of Toulon, CNRS, IRD, Marseille, France
| | - Sébastien Lacroix
- Scientific & Technological Expertise Department, Veolia, Maisons-Laffitte, France
| | - Léa Cabrol
- MIO, Aix Marseille University, University of Toulon, CNRS, IRD, Marseille, France
- Instituto de Ecologia y Biodiversidad (IEB) Facultad de Ciencias, Universidad de Chile Las Palmeras, Nunoa, Santiago, Chile
| |
Collapse
|
16
|
Shi Z, Usman M, He J, Chen H, Zhang S, Luo G. Combined microbial transcript and metabolic analysis reveals the different roles of hydrochar and biochar in promoting anaerobic digestion of waste activated sludge. WATER RESEARCH 2021; 205:117679. [PMID: 34600232 DOI: 10.1016/j.watres.2021.117679] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/12/2021] [Accepted: 09/17/2021] [Indexed: 06/13/2023]
Abstract
Hydrothermal pretreatment of waste activated sludge (WAS) could eliminate the rate limiting step of anaerobic digestion (AD) -hydrolysis. However, the high organic loading rate may cause acid accumulation, thus leading to an unstable system. This study compared the effect of different hydrochar (HC2-260°C and HC3-320°C) and biochar (BC5-500°C and BC7-700°C) on AD of hydrothermal pretreated WAS (HPS). Results demonstrated that hydrochar was superior to biochar in the methane yield and production rate, especially HC2. HC2 had the highest surface oxygen-containing functional groups that could facilitate direct interspecies electron transfer (DIET). The enhanced methane yield was related with the increased protein utilization, and hydrochar and biochar enriched different microbes related to protein degradation. Metabolomic analysis showed the significantly changed metabolites induced by hydrochar and biochar were involved in fatty acids and amino acids-related metabolism, indicating the rapid conversion of intermediated products, which was consistent with the microbial community structure results. Hydrochar and biochar also induced upregulation of metabolites related to microbial metabolic activity and extracellular electron transfer. Although biochar induced the same metabolic changes, the alterations of these metabolites were weaker than those of hydrochar. The results of this study offered new insights into the molecular mechanisms of enhanced AD of HPS by hydrochar and biochar.
Collapse
Affiliation(s)
- Zhijian Shi
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Muhammad Usman
- Bioproducts Science and Engineering Laboratory, Washington State University (WSU), Tri-Cities, WA 99354, United States
| | - Jun He
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Huihui Chen
- College of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Shicheng Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Gang Luo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
| |
Collapse
|
17
|
Hao L, Fan L, Chapleur O, Guenne A, Bize A, Bureau C, Lü F, He P, Bouchez T, Mazéas L. Gradual development of ammonia-induced syntrophic acetate-oxidizing activities under mesophilic and thermophilic conditions quantitatively tracked using multiple isotopic approaches. WATER RESEARCH 2021; 204:117586. [PMID: 34474248 DOI: 10.1016/j.watres.2021.117586] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/13/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Insights into microbiota adaptation to increased ammonia stress, and identification of indicator microorganisms can help to optimize the operation of anaerobic digesters. To identify microbial indicators and investigate their metabolic contribution to acetoclastic methanogenesis (AM), syntrophic acetate oxidation (SAO) or hydrogenotrophic methanogenesis (HM), 40 anaerobic batch reactors fed with acetate of 110 mmol/L were set up at NH4+-N concentrations of 0.14 g/L, 5.00 g/L or 7.00 g/L, inoculated with thermophilic or mesophilic microbiota with or without pre-exposure to ammonia stress. Four stable carbon isotope probing approaches were applied in parallel, with [1,2-13C]-CH3COOH, [2-13C]-CH3COOH, [13C]NaHCO3 or non-labeled CH3COOH used individually. The last three approaches were used to quantify the methanogenic pathways by tracking labeled 13C or natural 13C signatures in the resulting CH4 and CO2, and consistently detected the dynamic transition of dominant pathways from AM to SAO-HM under ammonia stress. Results of quantitative PCR and fluorescence in-situ hybridization illustrated the procedure, acetotrophic methanogens being outcompeted by acetate-oxidizing syntrophs. The first and last isotope-labeling approaches were designed to probe the active acetate-mineralizing microbes with DNA-SIP. Known acetate-oxidizing bacteria like Syntrophaceticus and Tepidanaerobacter, as well as novel members of Pseudomonas, Bacillus and Symbiobacteraceae were detected, with Methanoculleus as the predominant H2/CO2-utilizing partner. Using NanoSIMS, some bacterial cells were observed to be fixing CO2 from [13C]NaHCO3. In this study, Methanosaeta was only active with ammonia < 200 mg-N/L; the syntrophs catalyzing SAO-HM started to compete with AM-conducting Methanosarcina at intermediate concentrations of ammonia, i.e. 200-500 mg-N/L, and outcompeted the acetotrophic methanogens with ammonia > 500 mg-N/L. Under ammonia stress, diverse known and novel microbial taxa were involved in acetate mineralization, comparable with those identified in previous studies.
Collapse
Affiliation(s)
- Liping Hao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Lu Fan
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Olivier Chapleur
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Angéline Guenne
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Ariane Bize
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Chrystelle Bureau
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Fan Lü
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China
| | - Pinjing He
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China.
| | - Théodore Bouchez
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France.
| | - Laurent Mazéas
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France.
| |
Collapse
|
18
|
Singh A, Moestedt J, Berg A, Schnürer A. Microbiological Surveillance of Biogas Plants: Targeting Acetogenic Community. Front Microbiol 2021; 12:700256. [PMID: 34484143 PMCID: PMC8415747 DOI: 10.3389/fmicb.2021.700256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 07/21/2021] [Indexed: 11/15/2022] Open
Abstract
Acetogens play a very important role in anaerobic digestion and are essential in ensuring process stability. Despite this, targeted studies of the acetogenic community in biogas processes remain limited. Some efforts have been made to identify and understand this community, but the lack of a reliable molecular analysis strategy makes the detection of acetogenic bacteria tedious. Recent studies suggest that screening of bacterial genetic material for formyltetrahydrofolate synthetase (FTHFS), a key marker enzyme in the Wood-Ljungdahl pathway, can give a strong indication of the presence of putative acetogens in biogas environments. In this study, we applied an acetogen-targeted analyses strategy developed previously by our research group for microbiological surveillance of commercial biogas plants. The surveillance comprised high-throughput sequencing of FTHFS gene amplicons and unsupervised data analysis with the AcetoScan pipeline. The results showed differences in the acetogenic community structure related to feed substrate and operating parameters. They also indicated that our surveillance method can be helpful in the detection of community changes before observed changes in physico-chemical profiles, and that frequent high-throughput surveillance can assist in management towards stable process operation, thus improving the economic viability of biogas plants. To our knowledge, this is the first study to apply a high-throughput microbiological surveillance approach to visualise the potential acetogenic population in commercial biogas digesters.
Collapse
Affiliation(s)
- Abhijeet Singh
- Anaerobic Microbiology and Biotechnology Group, Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Jan Moestedt
- Tekniska Verken i Linköping AB, Department R&D, Linköping, Sweden
| | | | - Anna Schnürer
- Anaerobic Microbiology and Biotechnology Group, Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| |
Collapse
|
19
|
Yue Y, Wang J, Wu X, Zhang J, Chen Z, Kang X, Lv Z. The fate of anaerobic syntrophy in anaerobic digestion facing propionate and acetate accumulation. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 124:128-135. [PMID: 33611157 DOI: 10.1016/j.wasman.2021.01.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 11/30/2020] [Accepted: 01/31/2021] [Indexed: 06/12/2023]
Abstract
How the acetate and propionate accumulation impact anaerobic syntrophy during methane formation is not well understood. To investigate such effect, continuous acetate (35 g/L), propionate (11.25 g/L) and bicarbonate (30 g/L) supplementation were used during mesophilic anaerobic digestion. The high throughput sequencing (16S rRNA and mcrA), Real-Time quantitative PCR, and stable carbon isotope fingerprinting were applied to investigate the structure and activity of microbial community members. The results demonstrated that the abundance of syntrophic acetate oxidizing bacteria exhibited a gradual decrease coupled with heavier stable carbon isotopic signature of methane (δ 13CH4) in the three reagents impacted reactors. The increased acetate and propionate concentrations exerted negative influence on biogas production but the relatively stable hydrogenotrophic methanogens together with syntrophic acetate/propionate oxidizing bacteria kept the stable methane formation facing acetate and propionate accumulation. The functional genes copy number of the hydrogenotrophic Methanocellaceae and Methanomicrobiaceae correlated significantly with δ 13CH4 (R2 > 0.74), but only the abundance of Methanocellaceae fitted well with δ 13CH4 (p < 0.05). The δ 13CH4 signatures can predict methanogenesis, as it directly reflects the main methanogenic pathway; yet, further investigation of isotope fractionation in acetate/propionate coupled with δ 13CH4 is needed. Collectively, these results provide deep insight into anaerobic syntrophy and reveal changes of synergistic relationships, both of which may contribute to the stability of biogas reactors.
Collapse
Affiliation(s)
- Yanan Yue
- School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China
| | - Junyu Wang
- School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China
| | - Xiayuan Wu
- Bioenergy Research Institute, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Jianfeng Zhang
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zhongbing Chen
- Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500 Prague, Czech Republic.
| | - Xuejing Kang
- Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500 Prague, Czech Republic
| | - Zuopeng Lv
- School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China.
| |
Collapse
|
20
|
Niz MYK, Fuentes L, Etchebehere C, Zaiat M. Sugarcane vinasse extreme thermophilic digestion: a glimpse on biogas free management. Bioprocess Biosyst Eng 2021; 44:1405-1421. [PMID: 33721084 DOI: 10.1007/s00449-021-02517-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 01/23/2021] [Indexed: 10/21/2022]
Abstract
The high temperature in which sugarcane vinasse (SV) is generated (~ 90 °C) and the positive effect of higher temperatures in biochemical reactions have motivated the evaluation of SV anaerobic digestion (AD) under extreme temperature conditions. Two-stage (acidogenic/methanogenic) and single-stage (methanogenic) AD of SV were evaluated under 70 °C in structured-bed reactors. The extreme temperature was beneficial to the acidogenic step of the two-stage AD process. The methane production, however, was hindered at 70 °C. The VMP of the single and two-stage reactors accounted, respectively, for only 13% and 7% of the production rate reported in sugarcane vinasse AD at 55 °C. At 70 °C, the main genera responsible for methane production was Methanothermobacter and the acetoclastic methanogenesis did not occur, resulting in acetic acid build up (15,800 mg L-1). These results brought a new perspective for sugarcane vinasse management, with acetic acid production alternatively to methanization. In this perspective, two-stage process would be composed of acidogenic and acetogenic reactors, and beyond acetate, hydrogen and other soluble compounds could be recovered in a complete biorefinery process.
Collapse
Affiliation(s)
- Mirian Y K Niz
- Biological Processes Laboratory (LPB), São Carlos School of Engineering (EESC), University of São Paulo (USP), 1100 João Dagnone Avenue, São Carlos, São Paulo, Brazil.
| | - Laura Fuentes
- Microbial Community Laboratory, BioGem Department, Ministry of Education, Biological Research Institute Clemente Estable, Avenida Italia, 3318, Montevideo, Uruguay
| | - Claudia Etchebehere
- Microbial Community Laboratory, BioGem Department, Ministry of Education, Biological Research Institute Clemente Estable, Avenida Italia, 3318, Montevideo, Uruguay
| | - Marcelo Zaiat
- Biological Processes Laboratory (LPB), São Carlos School of Engineering (EESC), University of São Paulo (USP), 1100 João Dagnone Avenue, São Carlos, São Paulo, Brazil
| |
Collapse
|
21
|
Pan X, Zhao L, Li C, Angelidaki I, Lv N, Ning J, Cai G, Zhu G. Deep insights into the network of acetate metabolism in anaerobic digestion: focusing on syntrophic acetate oxidation and homoacetogenesis. WATER RESEARCH 2021; 190:116774. [PMID: 33387947 DOI: 10.1016/j.watres.2020.116774] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/18/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
Acetate is a pivotal intermediate product during anaerobic decomposition of organic matter. Its generation and consumption network is quite complex, which almost covers the most steps in anaerobic digestion (AD) process. Besides acidogenesis, acetogenesis and methanogenesis, syntrophic acetate oxidation (SAO) replaced acetoclastic methanogenesis to release the inhibition of AD at some special conditions, and the importance of considering homoacetogenesis had also been proved when analysing anaerobic fermentations. Syntrophic acetate-oxidizing bacteria (SAOB), with function of SAO, can survive under high temperature and ammonia/ volatile fatty acids (VFAs) concentrations, while, homoacetogens, performed homoacetogenesis, are more active under acidic, alkaline and low temperature (10°C-20°C) conditions, This review summarized the roles of SAO and homoacetogenesis in AD process, which contains the biochemical reactions, metabolism pathways, physiological characteristics and energy conservation of functional bacteria. The specific roles of these two processes in the subprocess of AD (i.e., acidogenesis, acetogenesis and methanogenesis) were also analyzed in detail. A two phases anaerobic digester is proposed for protein-rich waste(water) treatment by enhancing the functions of homoacetogens and SAOB compared to the traditional two-phases anaerobic digesters, in which the first phase is fermentation phase including acidogens and homoacetogens for acetate production, and second phase is a mixed culture coupling syntrophic fatty acids bacteria, SAOB and hydrogenotrophic methanogens for methane production. This review provides a new insight into the network on production and consumption of acetate in AD process.
Collapse
Affiliation(s)
- Xiaofang Pan
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
| | - Lixin Zhao
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agriculture Sciences, Beijing100081, China
| | - Chunxing Li
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | - Irini Angelidaki
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | - Nan Lv
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
| | - Jing Ning
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
| | - Guanjing Cai
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China
| | - Gefu Zhu
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen361021, China.
| |
Collapse
|
22
|
Liang Z, Xu G, Shi J, Yu S, Lu Q, Liang D, Sun L, Wang S. Sludge digestibility and functionally active microorganisms in methanogenic sludge digesters revealed by E. coli-fed digestion and microbial source tracking. ENVIRONMENTAL RESEARCH 2021; 193:110539. [PMID: 33253703 DOI: 10.1016/j.envres.2020.110539] [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: 08/25/2020] [Revised: 10/19/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
Methanogenic sludge digestion plays a pivotal role in attenuating and hygienizing the massively-produced waste activated sludge (WAS), which is predominantly composed of microbial cells and extracellular polymeric substances (EPS). The efficient sludge digestion requires a variety of functionally active microorganisms working together closely to convert sludge organic matter into biogas. Nonetheless, the digestion efficiency (or digestibility quantified as carbon removal efficiency) of major sludge constituents (i.e., microbial cells and EPS) and associated functionally active microorganisms in sludge digesters remain elusive. In this study, we identified the digestibility of sludge microbial cells and the associated functionally active microorganisms by using Escherichia coli (E. coli)-fed digestion and microbial source tracking. The average carbon removals in four digesters fed with fresh WAS (WAS-AD), thermal pretreated WAS (Thermal-WAS-AD), E. coli cells (E.coli-AD) and thermal pretreated E. coli cells (Thermal-E.coli-AD) were 30.6 ± 3.4%, 45.8 ± 2.9%, 69.0 ± 3.4% and 68.9 ± 4.6%, respectively. Compared to WAS-AD and Thermal-WAS-AD, the significantly higher carbon removals in E. coli-AD and Thermal-E. coli-AD suggested the remarkably higher digestibility of microbial cells than EPS, and releasing organic matter from EPS might be a rate-limiting step in sludge digestion. Functionally active microorganisms for microbial cell digestion predominantly included fermenters (e.g., Petrimonas and Lentimicrobium), syntrophic acetogens (e.g., Synergistaceae) and methanogens (e.g., Methanosaeta and Methanosarcina). Microbial source tracking estimation showed that the microbial cell-digesting populations accounted for 35.6 ± 9.1% and 70.3 ± 10.1% of total microbial communities in the WAS-AD and Thermal-WAS-AD, respectively. Accordingly, the functionally active microorganisms for digestion of both microbial cells and EPS accounted for 64.5 ± 12.1% and 97.3 ± 2.0% of total digestion sludge microbiome in WAS-AD and Thermal-WAS-AD, respectively. By contrast, feeding WAS-derived microorganisms accounted for 23.2 ± 4.4% and 2.3 ± 1.2% of total microbial communities in the WAS-AD and Thermal-WAS-AD, respectively.
Collapse
Affiliation(s)
- Zhiwei Liang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Guofang Xu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Jiangjian Shi
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Sining Yu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Qihong Lu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Dawei Liang
- Beijing Key Laboratory of Bio-inspired Energy Materials and Devices, School of Space & Environment, Beihang University, Beijing, 100191, China
| | - Lianpeng Sun
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Shanquan Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China.
| |
Collapse
|
23
|
Prem EM, Mutschlechner M, Stres B, Illmer P, Wagner AO. Lignin intermediates lead to phenyl acid formation and microbial community shifts in meso- and thermophilic batch reactors. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:27. [PMID: 33472684 PMCID: PMC7816434 DOI: 10.1186/s13068-020-01855-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 12/09/2020] [Indexed: 05/10/2023]
Abstract
BACKGROUND Lignin intermediates resulting from lignocellulose degradation have been suspected to hinder anaerobic mineralisation of organic materials to biogas. Phenyl acids like phenylacetate (PAA) are early detectable intermediates during anaerobic digestion (AD) of aromatic compounds. Studying the phenyl acid formation dynamics and concomitant microbial community shifts can help to understand the microbial interdependencies during AD of aromatic compounds and may be beneficial to counteract disturbances. RESULTS The length of the aliphatic side chain and chemical structure of the benzene side group(s) had an influence on the methanogenic system. PAA, phenylpropionate (PPA), and phenylbutyrate (PBA) accumulations showed that the respective lignin intermediate was degraded but that there were metabolic restrictions as the phenyl acids were not effectively processed. Metagenomic analyses confirmed that mesophilic genera like Fastidiosipila or Syntrophomonas and thermophilic genera like Lactobacillus, Bacillus, Geobacillus, and Tissierella are associated with phenyl acid formation. Acetoclastic methanogenesis was prevalent in mesophilic samples at low and medium overload conditions, whereas Methanoculleus spp. dominated at high overload conditions when methane production was restricted. In medium carbon load reactors under thermophilic conditions, syntrophic acetate oxidation (SAO)-induced hydrogenotrophic methanogenesis was the most important process despite the fact that acetoclastic methanogenesis would thermodynamically be more favourable. As acetoclastic methanogens were restricted at medium and high overload conditions, syntrophic acetate oxidising bacteria and their hydrogenotrophic partners could step in for acetate consumption. CONCLUSIONS PAA, PPA, and PBA were early indicators for upcoming process failures. Acetoclastic methanogens were one of the first microorganisms to be impaired by aromatic compounds, and shifts to syntrophic acetate oxidation coupled to hydrogenotrophic methanogenesis occurred in thermophilic reactors. Previously assumed associations of specific meso- and thermophilic genera with anaerobic phenyl acid formation could be confirmed.
Collapse
Affiliation(s)
- Eva Maria Prem
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, 6020, Innsbruck, Austria.
| | - Mira Mutschlechner
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, 6020, Innsbruck, Austria
| | - Blaz Stres
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
- Institute of Sanitary Engineering, Faculty of Civil and Geodetic Engineering, University of Ljubljana, Jamova 2, 1000, Ljubljana, Slovenia
- Department of Automation, Biocybernetics and Robotics, Jozef Štefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - Paul Illmer
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, 6020, Innsbruck, Austria
| | - Andreas Otto Wagner
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, 6020, Innsbruck, Austria
| |
Collapse
|
24
|
Meng L, Wang J, Li X, Yu Y, Zhu Y. Microbial community and molecular ecological network in the EGSB reactor treating antibiotic wastewater: Response to environmental factors. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111669. [PMID: 33396179 DOI: 10.1016/j.ecoenv.2020.111669] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/04/2020] [Accepted: 11/13/2020] [Indexed: 06/12/2023]
Abstract
In this study, one lab-scale EGSB reactor (1.47 L volume) was designed to treat the antibiotic wastewater under different environmental factors, including the addition of cephalexin (CFX), Temperature (T) and Hydraulic Retention Time (HRT). The microbial community structure in EGSB reactor was analyzed with high-throughput sequencing technology to investigate their response to environmental factors changes, and then the random-matrix-theory (RMT)-based network analysis was used to investigate the microbial community's molecular ecological network in EGSB systems treating antibiotics wastewater. Moreover, the explanatory value of each environmental factor on the change of microbial community structure was obtained through the result of redundancy analysis (RDA). The results showed that the addition of cephalexin (CFX), decline of T and decline of HRT (8 h) would decrease the removal efficiency of COD decreasing. And the removal efficiency of CFX would not be affected by decline of T and HRT, except the producing and degrading process of CFX by-products was changed obviously. The result of RDA analysis suggested the environmental factors mainly affected bacterial and fungal microbial community structure but not archaeal ones. The result of high-throughput sequencing showed the relative abundance (RA) of Firmicutes had been obviously affected by T and HRT, which might be main reason leading to the decrease of COD removal efficiency. In addition, molecular ecological network analysis showed the growth of Bacteroidetes occupied the niche of functional microorganism and led to the unstable operation of EGSB when T declined. What's more, the molecular ecological network analysis revealed that Exophiala which belonged to fungi Ascomycota phylum was the hub genus to degrade complex refractory organic pollutants, and Aceticlastic methanogens Methanosaeta was the core functional archaea genus.
Collapse
Affiliation(s)
- Lingwei Meng
- School of Civil Engineering and Architecture, Northeast Electric Power University, Jilin 132012, China.
| | - Jichao Wang
- School of Civil Engineering and Architecture, Northeast Electric Power University, Jilin 132012, China
| | - Xiangkun Li
- School of Civil and Transportation, Hebei University of Technology, Tianjin 300401, China
| | - Yening Yu
- School of Transportation Science and Engineering, Harbin Institute of Technology, Harbin 150090, China.
| | - Yining Zhu
- Jilin Petro-chemical Company Power First Plant, Jilin 13202, China
| |
Collapse
|
25
|
Christou ML, Vasileiadis S, Kalamaras SD, Karpouzas DG, Angelidaki I, Kotsopoulos TA. Ammonia-induced inhibition of manure-based continuous biomethanation process under different organic loading rates and associated microbial community dynamics. BIORESOURCE TECHNOLOGY 2021; 320:124323. [PMID: 33157441 DOI: 10.1016/j.biortech.2020.124323] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/17/2020] [Accepted: 10/23/2020] [Indexed: 05/23/2023]
Abstract
Three Continuously Stirred Tank Reactors (CTSRs) were operating at steady state conditions with Organic Loading Rates (OLR) of 2.09, 3.024 and 4.0 g VS L-1 d-1. Glucose was used as the sole factor for increasing the OLR, linking the increase of the OLR with the C/N ratio increase. The reactors were stressed by increasing the ammonia concentration to 5 g L-1 from 1.862 g L-1. The results showed elevating inhibition of the anaerobic process by increasing the C/N ratio just by increasing the OLR, under the high ammonia concentration. A different response of the bacterial and archaeal community under ammonia stressed conditions was also observed. Under the high ammonia concentration, hydrogen-depended methylotrophic was the dominant methanogenesis route at OLR of 2.09 g VS L-1d-1, while the hydrogenotrophic route was the dominant at the high OLR of 4 g VS L-1d-1, which coincided with high acetate and propionate concentrations.
Collapse
Affiliation(s)
- M L Christou
- Department of Hydraulics, Soil Science and Agricultural Engineering, School of Agriculture, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece
| | - S Vasileiadis
- Department of Biochemistry and Biotechnology, University of Thessaly, GR-41500 Larissa, Greece
| | - S D Kalamaras
- Department of Hydraulics, Soil Science and Agricultural Engineering, School of Agriculture, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece
| | - D G Karpouzas
- Department of Biochemistry and Biotechnology, University of Thessaly, GR-41500 Larissa, Greece
| | - I Angelidaki
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - T A Kotsopoulos
- Department of Hydraulics, Soil Science and Agricultural Engineering, School of Agriculture, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
| |
Collapse
|
26
|
Symbiotic chitin degradation by a novel anaerobic thermophilic bacterium Hydrogenispora sp. UUS1-1 and the bacterium Tepidanaerobacter sp. GT38. Enzyme Microb Technol 2020; 144:109740. [PMID: 33541575 DOI: 10.1016/j.enzmictec.2020.109740] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 11/26/2020] [Accepted: 12/24/2020] [Indexed: 01/21/2023]
Abstract
Chitin is the second most abundant organic compound in nature. Although mesophilic bacteria degrade insoluble chitin, there is a paucity of data describing degradation of insoluble chitin by anaerobic thermophilic bacteria. In this report, we screened cow manure compost for new chitin degradation systems, and identified a chitinolytic bacterial community (CBC) that showed high chitin degradation activity under thermophilic conditions, i.e., 1% (w/v) chitin powder degraded completely within 7 days at 60 °C. Metagenomic analysis revealed that the CBC was dominated by two bacterial genera from Hydrogenispora, an uncultured taxonomic group, and Tepidanaerobacter. Hydrogenispora were abundant in the early-to-mid stages of culturing with chitin, whereas the population of Tepidanaerobacter increased during the later stages of culturing. Strains UUS1-1 and GT38, which were isolated as pure cultures using the roll-tube method with colloidal chitin, N-acetyl-d-glucosamine, and glucose as carbon sources, were found to be closely related to H. ethanolica and T. acetatoxydans, respectively. Strain UUS1-1 readily degraded chitin and is the first anaerobic thermophilic chitinolytic bacterium reported, whereas strain GT38 showed no chitinolytic activity. Based on phylogenetic analysis, UUS1-1 and GT38 should be classified as novel genera and species. Zymogram analysis revealed that UUS1-1 produces at least two chitinases with molecular weights of 150 and 40 kDa. A coculture of UUS1-1 and GT38 degraded crystalline chitin faster with lower accumulation of lactate compared with UUS1-1 alone, indicating that the strains maintained a symbiotic association through assimilation of organic acids in chitin degradation and that strain GT38 consumed end-products to reduce end-product inhibition and enhance the degradation of crystalline chitin.
Collapse
|
27
|
Sakamoto S, Nobu MK, Mayumi D, Tamazawa S, Kusada H, Yonebayashi H, Iwama H, Ikarashi M, Wakayama T, Maeda H, Sakata S, Tamura T, Nomura N, Kamagata Y, Tamaki H. Koleobacter methoxysyntrophicus gen. nov., sp. nov., a novel anaerobic bacterium isolated from deep subsurface oil field and proposal of Koleobacteraceae fam. nov. and Koleobacterales ord. nov. within the class Clostridia of the phylum Firmicutes. Syst Appl Microbiol 2020; 44:126154. [PMID: 33227632 DOI: 10.1016/j.syapm.2020.126154] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/28/2020] [Accepted: 11/02/2020] [Indexed: 11/16/2022]
Abstract
An anaerobic thermophilic, rod-shaped bacterium possessing a unique non-lipid sheathed-like structure enveloping a single-membraned cell, designated strain NRmbB1T was isolated from at the deep subsurface oil field located in Yamagata Prefecture, Japan. Growth occurred with 40-60°C (optimum, 55°C), 0-2% (2%), NaCl and pH 6.0-8.5 (8.0). Fermentative growth with various sugars was observed. Glucose-grown cells generated acetate, hydrogen, pyruvate and lactate as the main end products. Syntrophic growth occurred with glucose, pyruvate and 3,4,5-trimethoxybenzoate in the presence of an H2-scavenging partner, and growth on 3,4,5-trimethoxybenzoate was only observed under syntrophic condition. The predominant cellular fatty acids were C16:0, iso-C16:0, anteiso-C15:0, and iso-C14:0. Respiratory quinone was not detected. The genomic G+C content was 40.8mol%. Based on 16S rRNA gene phylogeny, strain NRmbB1T belongs to a distinct order-level clade in the class Clostridia of the phylum Firmicutes, sharing low similarity with other isolated organisms (i.e., 87.5% for top hit Moorella thermoacetica DSM 2955T). In total, chemotaxonomic, phylogenetic and genomic characterization revealed that strain NRmbB1T (=KCTC 25035T, =JCM 39120T) represents a novel species of a new genus. In addition, we also propose the associated family and order as Koleobacteraceae fam. nov and Koleobacterales ord. nov., respectively.
Collapse
Affiliation(s)
- Sachiko Sakamoto
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; JST ERATO Nomura Microbial Community Control Project, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Masaru K Nobu
- Bioproduction Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8566, Japan.
| | - Daisuke Mayumi
- Institute for Geo-Resources and Environment, Geological Survey of Japan, AIST, 1-1-1, Higashi, Tsukuba 305-8566, Ibaraki, Japan
| | - Satoshi Tamazawa
- Bioproduction Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8566, Japan; Northern Advancement Center for Science & Technology, H-RISE, 5-3 Sakae-machi, Horonobe-cho, Teshio-gun, BPRI, Hokkaido 098-3221, Japan
| | - Hiroyuki Kusada
- JST ERATO Nomura Microbial Community Control Project, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Bioproduction Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8566, Japan
| | - Hideharu Yonebayashi
- Technical Research Center, INPEX CORPORATION, 9-23-30, Kitakarasuyama, Setagaya, 157-0061, Tokyo, Japan
| | - Hiroki Iwama
- Technical Research Center, INPEX CORPORATION, 9-23-30, Kitakarasuyama, Setagaya, 157-0061, Tokyo, Japan
| | - Masayuki Ikarashi
- Technical Research Center, INPEX CORPORATION, 9-23-30, Kitakarasuyama, Setagaya, 157-0061, Tokyo, Japan
| | - Tatsuki Wakayama
- Technical Research Center, INPEX CORPORATION, 9-23-30, Kitakarasuyama, Setagaya, 157-0061, Tokyo, Japan
| | - Haruo Maeda
- Institute for Geo-Resources and Environment, Geological Survey of Japan, AIST, 1-1-1, Higashi, Tsukuba 305-8566, Ibaraki, Japan; Technical Research Center, INPEX CORPORATION, 9-23-30, Kitakarasuyama, Setagaya, 157-0061, Tokyo, Japan
| | - Susumu Sakata
- Institute for Geo-Resources and Environment, Geological Survey of Japan, AIST, 1-1-1, Higashi, Tsukuba 305-8566, Ibaraki, Japan
| | - Tomohiro Tamura
- Bioproduction Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8566, Japan; Computational Bio Big-Data Open Innovation Laboratory (CBBD-OIL), AIST, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan
| | - Nobuhiko Nomura
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; JST ERATO Nomura Microbial Community Control Project, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yoichi Kamagata
- Bioproduction Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8566, Japan
| | - Hideyuki Tamaki
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; JST ERATO Nomura Microbial Community Control Project, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Bioproduction Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8566, Japan.
| |
Collapse
|
28
|
Wei Y, Wu Y, Zhang L, Zhou Z, Zhou H, Yan X. Genome recovery and metatranscriptomic confirmation of functional acetate-oxidizing bacteria from enriched anaerobic biogas digesters. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 265:114843. [PMID: 32480003 DOI: 10.1016/j.envpol.2020.114843] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 05/14/2020] [Accepted: 05/17/2020] [Indexed: 06/11/2023]
Abstract
In many cases, it is difficult to isolate the key microbial organisms from their communities present in natural environments. Metagenomic methods can recover near-complete genomes of the dominant microbial organisms in communities, and metatrancriptomic data could further reveal important genes and pathways related to their functions. In this study, three draft genomes of Clostridium ultunense-like bacteria were recovered based on metagenomic analyses, which is an essential syntrophic acetate-oxidizing bacteria (SAOB) member for maintaining high methane production in high-ammonium biogas digesters but difficult to isolate from its syntrophic partners. Firstly, syntrophic acetate-oxidizing bacteria in a microbial community series were enriched from a biogas digester by adding sodium acetate in the medium. Global analyses of C. ultunense suggested that it would combine the pyruvate-serine-glycine pathway and part of the Wood-Ljungdahl pathway for syntrophic acetate oxidization. Moreover, metatranscriptomic analyses showed that all of the genes of the proposed syntrophic acetate-oxidizing pathway present in the genome were actively transcribed in the microbiota. The functional bacterial enrichment and refined assembly method identify rare microbial genome in complex natural microbiota, which help to recover the syntrophic acetate-oxidizing pathway in C. ultunense strains in this study.
Collapse
Affiliation(s)
- Yongjun Wei
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China; School of Pharmaceutical Sciences, Key Laboratory of State Ministry of Education, Key Laboratory of Henan Province for Drug Quality Control and Evaluation, Collaborative Innovation Center of New Drug Research and Safety Evaluation, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan, 450001, China
| | - Yuqian Wu
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Lei Zhang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Zhihua Zhou
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Haokui Zhou
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
| | - Xing Yan
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
| |
Collapse
|
29
|
Chen YT, Zeng Y, Li J, Zhao XY, Yi Y, Gou M, Kamagata Y, Narihiro T, Nobu MK, Tang YQ. Novel Syntrophic Isovalerate-Degrading Bacteria and Their Energetic Cooperation with Methanogens in Methanogenic Chemostats. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:9618-9628. [PMID: 32667198 DOI: 10.1021/acs.est.0c01840] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Isovalerate is an important intermediate in anaerobic degradation of proteins/amino acids. Little is known about how this compound is degraded due to challenges in cultivation and characterization of isovalerate-degrading bacteria, which are thought to symbiotically depend on methanogenic archaea. In this study, we successfully enriched novel syntrophic isovalerate degraders (uncultivated Clostridiales and Syntrophaceae members) through operation of mesophilic and thermophilic isovalerate-fed anaerobic reactors. Metagenomics- and metatranscriptomics-based metabolic reconstruction of novel putative syntrophic isovalerate metabolizers uncovered the catabolic pathway and byproducts (i.e., acetate, H2, and formate) of isovalerate degradation, mechanisms for electron transduction from isovalerate degradation to H2 and formate generation (via electron transfer flavoprotein; ETF), and biosynthetic metabolism. The identified organisms tended to prefer formate-based interspecies electron transfer with methanogenic partners. The byproduct acetate was further converted to CH4 and CO2 by either Methanothrix (mesophilic) and Methanosarcina (thermophilic), which employed different approaches for acetate degradation. This study presents insights into novel mesophilic and thermophilic isovalerate degraders and their interactions with methanogens.
Collapse
Affiliation(s)
- Ya-Ting Chen
- Institute for Disaster Management and Reconstruction, Sichuan University-Hong Kong Polytechnic University, Chengdu, Sichuan 610207, China
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Yan Zeng
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Jie Li
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Xin-Yu Zhao
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Yue Yi
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Min Gou
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Yoichi Kamagata
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki 305-8566, Japan
| | - Takashi Narihiro
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki 305-8566, Japan
| | - Masaru Konishi Nobu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki 305-8566, Japan
| | - Yue-Qin Tang
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| |
Collapse
|
30
|
Dyksma S, Jansen L, Gallert C. Syntrophic acetate oxidation replaces acetoclastic methanogenesis during thermophilic digestion of biowaste. MICROBIOME 2020; 8:105. [PMID: 32620171 PMCID: PMC7334858 DOI: 10.1186/s40168-020-00862-5] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 05/11/2020] [Indexed: 05/19/2023]
Abstract
BACKGROUND Anaerobic digestion (AD) is a globally important technology for effective waste and wastewater management. In AD, microorganisms interact in a complex food web for the production of biogas. Here, acetoclastic methanogens and syntrophic acetate-oxidizing bacteria (SAOB) compete for acetate, a major intermediate in the mineralization of organic matter. Although evidence is emerging that syntrophic acetate oxidation is an important pathway for methane production, knowledge about the SAOB is still very limited. RESULTS A metabolic reconstruction of metagenome-assembled genomes (MAGs) from a thermophilic solid state biowaste digester covered the basic functions of the biogas microbial community. Firmicutes was the most abundant phylum in the metagenome (53%) harboring species that take place in various functions ranging from the hydrolysis of polymers to syntrophic acetate oxidation. The Wood-Ljungdahl pathway for syntrophic acetate oxidation and corresponding genes for energy conservation were identified in a Dethiobacteraceae MAG that is phylogenetically related to known SAOB. 16S rRNA gene amplicon sequencing and enrichment cultivation consistently identified the uncultured Dethiobacteraceae together with Syntrophaceticus, Tepidanaerobacter, and unclassified Clostridia as members of a potential acetate-oxidizing core community in nine full-scare digesters, whereas acetoclastic methanogens were barely detected. CONCLUSIONS Results presented here provide new insights into a remarkable anaerobic digestion ecosystem where acetate catabolism is mainly realized by Bacteria. Metagenomics and enrichment cultivation revealed a core community of diverse and novel uncultured acetate-oxidizing bacteria and point to a particular niche for them in dry fermentation of biowaste. Their genomic repertoire suggests metabolic plasticity besides the potential for syntrophic acetate oxidation. Video Abstract.
Collapse
Affiliation(s)
- Stefan Dyksma
- Faculty of Technology, Microbiology - Biotechnology, University of Applied Sciences Emden/Leer, Emden, Germany.
| | - Lukas Jansen
- Faculty of Technology, Microbiology - Biotechnology, University of Applied Sciences Emden/Leer, Emden, Germany
| | - Claudia Gallert
- Faculty of Technology, Microbiology - Biotechnology, University of Applied Sciences Emden/Leer, Emden, Germany
| |
Collapse
|
31
|
Xu J, Bu F, Zhu W, Luo G, Xie L. Microbial Consortiums of Hydrogenotrophic Methanogenic Mixed Cultures in Lab-Scale Ex-Situ Biogas Upgrading Systems under Different Conditions of Temperature, pH and CO. Microorganisms 2020; 8:microorganisms8050772. [PMID: 32455626 PMCID: PMC7285331 DOI: 10.3390/microorganisms8050772] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 12/12/2022] Open
Abstract
In this study, hydrogenotrophic methanogenic mixed cultures taken from 13 lab-scale ex-situ biogas upgrading systems under different temperature (20–70 °C), pH (6.0–8.5), and CO (0–10%, v/v) variables were systematically investigated. High-throughput 16S rRNA gene sequencing was used to identify the microbial consortia, and statistical analyses were conducted to reveal the microbial diversity, the core functional microbes, and their correlative relationships with tested variables. Overall, bacterial community was more complex than the archaea community in all mixed cultures. Hydrogenotrophic methanogens Methanothermobacter, Methanobacterium, and Methanomassiliicoccus, and putative syntrophic acetate-oxidizing bacterium Coprothermobacter and Caldanaerobacter were found to predominate, but the core functional microbes varied under different conditions. Multivariable sensitivity analysis indicated that temperature (p < 0.01) was the crucial variable to determine the microbial consortium structures in hydrogenotrophic methanogenic mixed cultures. pH (0.01 < p < 0.05) significantly interfered with the relative abundance of dominant archaea. Although CO did not affect community (p > 0.1), some potential CO-utilizing syntrophic metabolisms might be enhanced. Understanding of microbial consortia in the hydrogenotrophic methanogenic mixed cultures related to environmental variables was a great advance to reveal the microbial ecology in microbial biogas upgrading process.
Collapse
Affiliation(s)
- Jun Xu
- The Yangtze River Water Environment Key Laboratory of the Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; (J.X.); (F.B.); (W.Z.)
| | - Fan Bu
- The Yangtze River Water Environment Key Laboratory of the Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; (J.X.); (F.B.); (W.Z.)
| | - Wenzhe Zhu
- The Yangtze River Water Environment Key Laboratory of the Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; (J.X.); (F.B.); (W.Z.)
| | - Gang Luo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200092, China;
| | - Li Xie
- The Yangtze River Water Environment Key Laboratory of the Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; (J.X.); (F.B.); (W.Z.)
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
- Correspondence:
| |
Collapse
|
32
|
Wang HZ, Li J, Yi Y, Nobu MK, Narihiro T, Tang YQ. Response to inhibitory conditions of acetate-degrading methanogenic microbial community. J Biosci Bioeng 2020; 129:476-485. [DOI: 10.1016/j.jbiosc.2019.10.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 09/23/2019] [Accepted: 10/07/2019] [Indexed: 12/21/2022]
|
33
|
Dynamic shifts within volatile fatty acid-degrading microbial communities indicate process imbalance in anaerobic digesters. Appl Microbiol Biotechnol 2020; 104:4563-4575. [PMID: 32219463 DOI: 10.1007/s00253-020-10552-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 03/04/2020] [Accepted: 03/15/2020] [Indexed: 10/24/2022]
Abstract
Buildup of volatile fatty acids (VFAs) in anaerobic digesters (ADs) often results in acidification and process failure. Understanding the dynamics of microbial communities involved in VFA degradation under stable and overload conditions may help optimize anaerobic digestion processes. In this study, five triplicate mesophilic completely mixed AD sets were operated at different organic loading rates (OLRs; 1-6 g chemical oxygen demand [COD] LR-1day-1), and changes in the composition and abundance of VFA-degrading microbial communities were monitored using amplicon sequencing and taxon-specific quantitative PCRs, respectively. AD sets operated at OLRs of 1-4 g COD LR-1day-1 were functionally stable throughout the operational period (120 days) whereas process instability (characterized by VFA buildup, pH decline, and decreased methane production rate) occurred in digesters operated at ≥ 5 g COD LR-1day-1. Though microbial taxa involved in propionate (Syntrophobacter and Pelotomaculum) and butyrate (Syntrophomonas) degradation were detected across all ADs, their abundance decreased with increasing OLR. The overload conditions also inhibited the proliferation of the acetoclastic methanogen, Methanosaeta, and caused a microbial community shift to acetate oxidizers (Tepidanaerobacter acetatoxydans) and hydrogenotrophic methanogens (Methanoculleus). This study's results highlight the importance of operating ADs with conditions that promote the maintenance of microbial communities involved in VFA degradation.
Collapse
|
34
|
Lackner N, Wagner AO, Markt R, Illmer P. pH and Phosphate Induced Shifts in Carbon Flow and Microbial Community during Thermophilic Anaerobic Digestion. Microorganisms 2020; 8:E286. [PMID: 32093251 PMCID: PMC7074938 DOI: 10.3390/microorganisms8020286] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 01/11/2023] Open
Abstract
pH is a central environmental factor influencing CH4 production from organic substrates, as every member of the complex microbial community has specific pH requirements. Here, we show how varying pH conditions (5.0-8.5, phosphate buffered) and the application of a phosphate buffer per se induce shifts in the microbial community composition and the carbon flow during nine weeks of thermophilic batch digestion. Beside monitoring the methane production as well as volatile fatty acid concentrations, amplicon sequencing of the 16S rRNA gene was conducted. The presence of 100 mM phosphate resulted in reduced CH4 production during the initial phase of the incubation, which was characterized by a shift in the dominant methanogenic genera from a mixed Methanosarcina and Methanoculleus to a pure Methanoculleus system. In buffered samples, acetate strongly accumulated in the beginning of the batch digestion and subsequently served as a substrate for methanogens. Methanogenesis was permanently inhibited at pH values ≤5.5, with the maximum CH4 production occurring at pH 7.5. Adaptations of the microbial community to the pH variations included shifts in the archaeal and bacterial composition, as less competitive organisms with a broad pH range were able to occupy metabolic niches at unfavorable pH conditions.
Collapse
Affiliation(s)
- Nina Lackner
- Department of Microbiology, Universität Innsbruck, 6020 Innsbruck, Austria; (A.O.W.); (R.M.); (P.I.)
| | | | | | | |
Collapse
|
35
|
Abstract
AbstractThe dwarf shrub Cressa cretica is a thermocosmopolitan halophilic species. Different mechanisms confer salt stress tolerance such as tissue and osmotic tolerance and ion exclusion, as well as the associated microbiota. The aims were (i) to investigate the best conditions for C. cretica seed germination and to examine the tolerance of germinated seeds and seedlings to different salt concentrations and (ii) to characterize the rhizosphere and bulk soil microbiota. Germination and growth experiments were conducted to address plant salt tolerance, and with Illumina sequencing the microbiota of rhizosphere and bulk soil was investigated. While high salt concentrations (600, 800, and 1000 mM NaCl) inhibited C.cretica seed germination, recovery of ungerminated seeds under non-saline conditions was high, indicating osmotic rather than toxic effects of high salt concentrations. The microbiota found in rhizosphere and bulk soil showed high similarity with that found in previous studies on halophyte-associated microbiota, among the Planctomyces, Halomonas and Jeotgalibacillus. Concluding, salt stress responses on the plant level were shown, as has the involvement of associated halotolerant bacteria. Still, the potential role for mitigating saline stress by the bacterial associates of C. cretica, most of them microbial dark matter, will have to be investigated, as will the contributions of archaea and fungi.
Collapse
|
36
|
Prem EM, Stres B, Illmer P, Wagner AO. Microbial community dynamics in mesophilic and thermophilic batch reactors under methanogenic, phenyl acid-forming conditions. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:81. [PMID: 32391081 PMCID: PMC7201606 DOI: 10.1186/s13068-020-01721-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 04/24/2020] [Indexed: 05/08/2023]
Abstract
BACKGROUND Proteinaceous wastes exhibit high theoretical methane yields and their residues are considered valuable fertilisers. The routine anaerobic degradation of proteins often raises problems like high aromatic compound concentrations caused by the entry of aromatic amino acids into the system. A profound investigation of the consequences of aromatic compound exposure on various microorganisms, which cascade-like and interdependently degrade complex molecules to biogas, is still pending. RESULTS In mesophilic samples, methane was predominantly produced via acetoclastic methanogenesis. The highest positive correlation was observed between phenylacetate (PAA) and Psychrobacter spp. and between phenylpropionate (PPA) and Haloimpatiens spp. Moreover, Syntrophus spp. negatively correlated with PAA (Spearman's rank correlations coefficient (rs) = - 0.46, p < 0.05) and PPA concentrations (rs = - 0.44, p < 0.05) and was also associated with anaerobic benzene ring cleavage. In thermophilic samples, acetate was predominantly oxidised by Tepidanaerobacter spp. or Syntrophaceticus spp. in syntrophic association with a hydrogenotrophic methanogen. The genera Sedimentibacter and Syntrophaceticus correlated positively with both PAA and PPA concentrations. Moreover, Sedimentibacter spp., Tepidanaerobacter spp., Acetomicrobium spp., and Sporanaerobacter spp. were significant LEfSe (linear discriminant analysis effect size) biomarkers for high meso- as well as thermophilic phenyl acid concentrations. Direct negative effects of phenyl acids on methanogenic properties could not be proven. CONCLUSIONS Anaerobic phenyl acid formation is not restricted to specific microbial taxa, but rather done by various meso- and thermophilic bacteria. The cleavage of the highly inert benzene ring is possible in methanogenic batch reactors-at least in mesophilic fermentation processes. The results indicated that phenyl acids rather affect microorganisms engaged in preceding degradation steps than the ones involved in methanogenesis.
Collapse
Affiliation(s)
- Eva Maria Prem
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria
| | - Blaz Stres
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
- Institute of Sanitary Engineering, Faculty of Civil and Geodetic Engineering, University of Ljubljana, Jamova 2, 1000 Ljubljana, Slovenia
- Department of Automation, Biocybernetics and Robotics, Jozef Štefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
| | - Paul Illmer
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria
| | - Andreas Otto Wagner
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria
| |
Collapse
|
37
|
Gou M, Wang H, Li J, Sun Z, Nie Y, Nobu MK, Tang Y. Different inhibitory mechanisms of chlortetracycline and enrofloxacin on mesophilic anaerobic degradation of propionate. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:1406-1416. [PMID: 31745805 DOI: 10.1007/s11356-019-06705-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 10/07/2019] [Indexed: 06/10/2023]
Abstract
In anaerobic digestion, propionate is a key intermediate whose degradation is thermodynamically challenging and accumulation is detrimental to the process. Many wastewater streams contain antibiotics due to its globally increasing use, and these compounds can inhibit methane production. However, the effect of antibiotics on propionate degradation in anaerobic digestion remains unclear. In this study, the influence of two antibiotics (chlortetracycline [CTC] and enrofloxacin [EFX]) on biogas production and mesophilic propionate-degrading microbial community was investigated. CTC strongly repressed propionate oxidation, acetate utilization, and methane production, while EFX only inhibited propionate oxidation and methane production to a lesser extent. Microbial community analyses showed that syntrophic propionate-oxidizing bacteria (SPOB) Syntrophobacter had strong tolerance to both CTC and EFX. CTC inhibition mainly acted on the activity of acetate-oxidizing bacteria (Mesotoga, Geovibrio, Tepidanaerobacter, unclassified Bacteroidetes, and unclassified Clostridia) and acetoclastic methanogen, while EFX inhibition applied to the SPOB Smithella and acetoclastic methanogen. Network analysis further indicated that more complicated correlation among bacterial genera occurred in CTC treatments. These results suggested that CTC and EFX inhibited propionate degradation via different mechanisms, which was the result of joint action by antibiotics and microbial interactions.
Collapse
Affiliation(s)
- Min Gou
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, 610065, Sichuan, China
| | - HuiZhong Wang
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, 610065, Sichuan, China
| | - Jie Li
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, 610065, Sichuan, China
| | - ZhaoYong Sun
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, 610065, Sichuan, China
| | - Yong Nie
- College of Engineering, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing, 100871, China
| | - Masaru Konishi Nobu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan
| | - YueQin Tang
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, 610065, Sichuan, China.
| |
Collapse
|
38
|
Description of Biomaibacter acetigenes gen. nov., sp. nov., and proposal of Thermosediminibacterales ord. nov. containing two novel families of Tepidanaerobacteraceae fam. nov. and Thermosediminibacteraceae fam. nov. Int J Syst Evol Microbiol 2019; 69:3891-3902. [DOI: 10.1099/ijsem.0.003701] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
39
|
Huang Y, Wang Y, Liu S, Huang W, He L, Zhou J. Enhanced hydrolysis-acidification of high-solids and low-organic-content sludge by biological thermal-alkaline synergism. BIORESOURCE TECHNOLOGY 2019; 294:122234. [PMID: 31610488 DOI: 10.1016/j.biortech.2019.122234] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/29/2019] [Accepted: 10/01/2019] [Indexed: 06/10/2023]
Abstract
In this study, a biological thermal-alkaline synergistic system was successfully established to enhance the hydrolysis-acidification efficiency of high-solids and low-organic-content sludge (HS-LOC-S). The results indicated that the highest hydrolysis rate was obtained at pH of 12 (52.62%) leading to the highest production of soluble chemical oxygen demand (SCOD) and soluble protein (SP). The highest acidification rate was observed at pH of 10 (32.15%), leading to the highest production of volatile fatty acids (VFAs). At pH of 10, average sludge size reduced by 24.60%, and the proportion of biodegradable dissolved organic matter (DOM) produced by synergistic system increased by 15.82%, when compared with those of raw sludge. Moreover, results of 16S rRNA clearly validated that the relative abundance of hydrolytic and acidogenic microbes (e.g. Tepidimicrobium, Coprothermobacter) abundantly enriched at pH of 10 (49.88%) was greatly higher than others, which was the main reason for its maximum VFAs accumulation.
Collapse
Affiliation(s)
- Yangyang Huang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Yingmu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Shihu Liu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Wei Huang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Lei He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China
| | - Jian Zhou
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China.
| |
Collapse
|
40
|
Keller A, Schink B, Müller N. Energy-Conserving Enzyme Systems Active During Syntrophic Acetate Oxidation in the Thermophilic Bacterium Thermacetogenium phaeum. Front Microbiol 2019; 10:2785. [PMID: 31849917 PMCID: PMC6895022 DOI: 10.3389/fmicb.2019.02785] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/15/2019] [Indexed: 11/13/2022] Open
Abstract
The thermophilic acetogen Thermacetogenium phaeum uses the Wood-Ljungdahl pathway (WLP) in both directions, either for the production of acetate from various compounds or for the oxidation of acetate in syntrophic cooperation with methanogens. In this study, energy-conserving enzyme systems in T. phaeum were investigated in both metabolic directions. A gene cluster containing a membrane-bound periplasmically oriented formate dehydrogenase directly adjacent to putative menaquinone synthesis genes was identified in the genome. The protein products of these genes were identified by total proteome analysis, and menaquinone MK-7 had been found earlier as the dominant quinone in the membrane. Enzyme assays with membrane preparations and anthraquinone-2,6-disulfonate as electron acceptor verified the presence of a quinone-dependent formate dehydrogenase. A quinone-dependent methylene-THF reductase is active in the soluble fraction and in the membrane fraction. From these results we conclude a reversed electron transport system from methyl-THF oxidation to CO2 reduction yielding formate as reduced product which is transferred to the methanogenic partner. The redox potential difference between methyl-THF (Eo' = -200 mV) and formate (Eo' = -432 mV) does not allow electron transfer through syntrophic formate removal alone. We postulate that part of the ATP conserved by substrate-level phosphorylation has to be invested into the generation of a transmembrane proton gradient by ATPase. This proton gradient could drive the endergonic oxidation of methyl-THF in an enzyme reaction similar to the membrane-bound reversed electron transport system previously observed in the syntrophically butyrate-oxidizing bacterium Syntrophomonas wolfei. To balance the overall ATP budget in acetate oxidation, we postulate that acetate is activated through an ATP-independent path via aldehyde:ferredoxin oxidoreductase (AOR) and subsequent oxidation of acetaldehyde to acetyl-CoA.
Collapse
Affiliation(s)
- Anja Keller
- Department of Biology, Universität Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology, Konstanz, Germany
| | - Bernhard Schink
- Department of Biology, Universität Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology, Konstanz, Germany
| | - Nicolai Müller
- Department of Biology, Universität Konstanz, Konstanz, Germany
| |
Collapse
|
41
|
Fernandez‐Gonzalez N, Pedizzi C, Lema JM, Carballa M. Air-side ammonia stripping coupled to anaerobic digestion indirectly impacts anaerobic microbiome. Microb Biotechnol 2019; 12:1403-1416. [PMID: 31532080 PMCID: PMC6801131 DOI: 10.1111/1751-7915.13482] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 06/26/2019] [Accepted: 08/13/2019] [Indexed: 11/29/2022] Open
Abstract
Air-side stripping without a prior solid-liquid phase separation step is a feasible and promising process to control ammonia concentration in thermophilic digesters. During the process, part of the anaerobic biomass is exposed to high temperature, high pH and aerobic conditions. However, there are no studies assessing the effects of those harsh conditions on the microbial communities of thermophilic digesters. To fill this knowledge gap, the microbiomes of two thermophilic digesters (55°C), fed with a mixture of pig manure and nitrogen-rich co-substrates, were investigated under different organic loading rates (OLR: 1.1-5.2 g COD l-1 day-1 ), ammonia concentrations (0.2-1.5 g free ammonia nitrogen l-1 ) and stripping frequencies (3-5 times per week). The bacterial communities were dominated by Firmicutes and Bacteroidetes phyla, while the predominant methanogens were Methanosarcina sp archaea. Increasing co-substrate fraction, OLR and free ammonia nitrogen (FAN) favoured the presence of genera Ruminiclostridium, Clostridium and Tepidimicrobium and of hydrogenotrophic methanogens, mainly Methanoculleus archaea. The data indicated that the use of air-side stripping did not adversely affect thermophilic microbial communities, but indirectly modulated them by controlling FAN concentrations in the digester. These results demonstrate the viability at microbial community level of air side-stream stripping process as an adequate technology for the ammonia control during anaerobic co-digestion of nitrogen-rich substrates.
Collapse
Affiliation(s)
- Nuria Fernandez‐Gonzalez
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
- Present address:
Present address:Department of Chemical Engineering and Environmental TechnologyValladolid UniversityDr. Mergelina, s/n47011ValladolidSpain
| | - Chiara Pedizzi
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
| | - Juan M. Lema
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
| | - Marta Carballa
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
| |
Collapse
|
42
|
Park SG, Rhee C, Shin SG, Shin J, Mohamed HO, Choi YJ, Chae KJ. Methanogenesis stimulation and inhibition for the production of different target electrobiofuels in microbial electrolysis cells through an on-demand control strategy using the coenzyme M and 2-bromoethanesulfonate. ENVIRONMENT INTERNATIONAL 2019; 131:105006. [PMID: 31330362 DOI: 10.1016/j.envint.2019.105006] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 06/23/2019] [Accepted: 07/09/2019] [Indexed: 06/10/2023]
Abstract
Electron allocation through the suppression or the stimulation of methanogenesis is critical for microbial electrolysis cells (MECs) to produce the desired target product (e.g., CH4 or H2). In this study, selective methanogenesis control using the coenzyme M (CoM) and 2-bromoethanesulfonate (2-BES) was investigated in a two-chambered MEC to evaluate the effect of CoM and 2-BES on the production of different electrobiofuels, net energy conversion efficiency and microbial community structure. Because the CoM is a crucial methyl-group carrier in the final process of methanogenesis, it was postulated that CoM would stimulate methanogenic activity at the anode, while a structural analog of the CoM (i.e., 2-BES) was expected to improve cathodic H2 yield using electrons conserved because of methanogen inhibition (electron equivalence: 8 mol e- = 1 mol CH4 = 4 mol H2). CoM injection in MECs significantly enhanced their CH4 production rate, purity, and yield by 4.5-fold, 14.5%, and 76.1%, respectively, compared to the control. Moreover, microbial community analysis indicated that Methanosaeta, the major acetoclastic methanogen, continued to dominate the microbial community but steadily decreased in relative abundance after the CoM injection. On the other hand, drastic increases in hydrogenotrophic methanogens, such as Methanoculleus and Methanolinea, were observed along with potential syntrophic acetate-oxidizing bacteria. In contrast, CH4 production in the 2-BES injected trials was significantly inhibited by 79.5%, resulting in a corresponding increase of H2 production by 145.5% compared to the control. Unlike the CoM, the microbial community did not noticeably change when 2-BES was injected, although the population size gradually decreased over time. Also, a single injection of CoM and 2-BES, even at low concentrations (500 μM), enabled the desired allocation of electrons as characterized by a high sensitivity, fast response, and negligible interference. In terms of energy conversion efficiency, methanogenesis stimulation approach resulted in higher net energy production than inhibition approach, whereas the remained electrons were not fully converted to hydrogen in case of the inhibition trial, thus producing less energy.
Collapse
Affiliation(s)
- Sung-Gwan Park
- Department of Environmental Engineering, College of Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 49112, South Korea
| | - Chaeyoung Rhee
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6 Naedong-ro, Naedong-myun, Jinju 52725, Republic of Korea
| | - Seung Gu Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6 Naedong-ro, Naedong-myun, Jinju 52725, Republic of Korea
| | - Juhee Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6 Naedong-ro, Naedong-myun, Jinju 52725, Republic of Korea
| | - Hend Omar Mohamed
- Department of Environmental Engineering, College of Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 49112, South Korea
| | - Yun-Jeong Choi
- Department of Environmental Engineering, College of Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 49112, South Korea
| | - Kyu-Jung Chae
- Department of Environmental Engineering, College of Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 49112, South Korea.
| |
Collapse
|
43
|
Identification of novel potential acetate-oxidizing bacteria in thermophilic methanogenic chemostats by DNA stable isotope probing. Appl Microbiol Biotechnol 2019; 103:8631-8645. [DOI: 10.1007/s00253-019-10078-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 06/30/2019] [Accepted: 07/31/2019] [Indexed: 01/04/2023]
|
44
|
Ziels RM, Nobu MK, Sousa DZ. Elucidating Syntrophic Butyrate-Degrading Populations in Anaerobic Digesters Using Stable-Isotope-Informed Genome-Resolved Metagenomics. mSystems 2019; 4:e00159-19. [PMID: 31387934 PMCID: PMC6687939 DOI: 10.1128/msystems.00159-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 07/12/2019] [Indexed: 11/20/2022] Open
Abstract
Linking the genomic content of uncultivated microbes to their metabolic functions remains a critical challenge in microbial ecology. Resolving this challenge has implications for improving our management of key microbial interactions in biotechnologies such as anaerobic digestion, which relies on slow-growing syntrophic and methanogenic communities to produce renewable methane from organic waste. In this study, we combined DNA stable-isotope probing (SIP) with genome-centric metagenomics to recover the genomes of populations enriched in 13C after growing on [13C]butyrate. Differential abundance analysis of recovered genomic bins across the SIP metagenomes identified two metagenome-assembled genomes (MAGs) that were significantly enriched in heavy [13C]DNA. Phylogenomic analysis assigned one MAG to the genus Syntrophomonas and the other MAG to the genus Methanothrix. Metabolic reconstruction of the annotated genomes showed that the Syntrophomonas genome encoded all the enzymes for beta-oxidizing butyrate, as well as several mechanisms for interspecies electron transfer via electron transfer flavoproteins, hydrogenases, and formate dehydrogenases. The Syntrophomonas genome shared low average nucleotide identity (<95%) with any cultured representative species, indicating that it is a novel species that plays a significant role in syntrophic butyrate degradation within anaerobic digesters. The Methanothrix genome contained the complete pathway for acetoclastic methanogenesis, indicating that it was enriched in 13C from syntrophic acetate transfer. This study demonstrates the potential of stable-isotope-informed genome-resolved metagenomics to identify in situ interspecies metabolic cooperation within syntrophic consortia important to anaerobic waste treatment as well as global carbon cycling.IMPORTANCE Predicting the metabolic potential and ecophysiology of mixed microbial communities remains a major challenge, especially for slow-growing anaerobes that are difficult to isolate. Unraveling the in situ metabolic activities of uncultured species may enable a more descriptive framework to model substrate transformations by microbiomes, which has broad implications for advancing the fields of biotechnology, global biogeochemistry, and human health. Here, we investigated the in situ function of mixed microbiomes by combining stable-isotope probing with metagenomics to identify the genomes of active syntrophic populations converting butyrate, a C4 fatty acid, into methane within anaerobic digesters. This approach thus moves beyond the mere presence of metabolic genes to resolve "who is doing what" by obtaining confirmatory assimilation of the labeled substrate into the DNA signature. Our findings provide a framework to further link the genomic identities of uncultured microbes with their ecological function within microbiomes driving many important biotechnological and global processes.
Collapse
Affiliation(s)
- Ryan M Ziels
- Department of Civil Engineering, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
| | - Masaru K Nobu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
| | - Diana Z Sousa
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, Netherlands
| |
Collapse
|
45
|
Youssef NH, Farag IF, Rudy S, Mulliner A, Walker K, Caldwell F, Miller M, Hoff W, Elshahed M. The Wood-Ljungdahl pathway as a key component of metabolic versatility in candidate phylum Bipolaricaulota (Acetothermia, OP1). ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:538-547. [PMID: 30888727 DOI: 10.1111/1758-2229.12753] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 03/15/2019] [Accepted: 03/18/2019] [Indexed: 06/09/2023]
Abstract
The Wood-Ljungdahl (WL) pathway is an important component of the metabolic machinery in multiple anaerobic prokaryotes, including numerous yet-uncultured bacterial phyla. The pathway can operate in the reductive and oxidative directions, enabling a wide range of metabolic processes. Here, we present a detailed analysis of 14 newly acquired, previously analysed, and publicly available genomic assemblies belonging to the candidate phylum Bipolaricaulota (candidate division OP1, and candidatus Acetothermia), where the occurrence of WL pathway appears to be universal. In silico analysis of predicted metabolic capabilities indicates that the pathway enables homoacetogenic fermentation of sugars and amino acids in all three Bipolaricaulota orders (RBG-16-55-9, UBA7950 and Bipolaricaulales). In addition, members of RBG-16-55-9 appear to possess the additional capacity for syntrophic acetate oxidation using the WL pathway; as well as for respiratory growth using oxygen or nitrate. Anabolically, all UBA7950, and the majority of the Bipolaricaulales genomes possess the capacity for autotrophic growth using the WL pathway. Our results highlight the WL-enabled metabolic versatility in the Bipolaricaulota, emphasize the need for examining the WL pathway in context of the overall metabolic circuitry in uncultured taxa, and demonstrate the value of comparative genomic analysis for providing a detailed overview of metabolic potential in a target microbial lineage and its potential functional niche in an ecosystem.
Collapse
Affiliation(s)
- Noha H Youssef
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Ibrahim F Farag
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Sydney Rudy
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Ace Mulliner
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Kara Walker
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Ford Caldwell
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Malik Miller
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Wouter Hoff
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| | - Mostafa Elshahed
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74074, USA
| |
Collapse
|
46
|
Yang F, Li W, Liu C, Wang M, Li Q, Sun Y. Impact of total carbon/sulfate on methane production and sulfate removal from co-digestion of sulfate-containing wastewater and corn stalk. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 243:411-418. [PMID: 31103687 DOI: 10.1016/j.jenvman.2019.04.129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/04/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
During the process of preparing furfural by straw depolymerization with dilute sulfuric acid, large amounts of high temperature sulfate-rich organic wastewater were produced. It cannot be treated directly by anaerobic digestion and converted to bioenergy due to high concentrations of sulfate. In this study, anaerobic co-digestion of sulfate containing wastewater and corn stalk was performed at thermophilic conditions to investigate the influences of total carbon (TC)/sulfate (6, 16, 35 and 110) on methane production and sulfate removal. The results showed that the highest methane production of 260.14 mL g-1 volatile solid (VS) was achieved at TC/sulfate of 35, which was significantly higher than 12.53 mL g-1 VS obtained at TC/sulfate of 6. Moreover, the results of sulfate balance analysis showed a maximum sulfate removal of 93.43% was achieved at TC/sulfate of 16, and sulfate concentration in biogas slurry was less than 0.1 g/L regardless of TC/sulfate after 28 days of co-digestion. The microbial community was analyzed using 16S rDNA sequencing technology, the results showed that methane was mainly produced by Methanoculleus and Methanosarcina, and sulfate was removed via Desulfotomaculum, and the relative abundance of methanogenic archaea (MA) and sulfate reducing bacteria (SRB) were significantly correlated with methane production and sulfate removal. It can concluded that higher methane production and sulfate removal can be obtained by anaerobic co-digestion of sulfate containing wastewater and corn stalk at properly TC/sulfate.
Collapse
Affiliation(s)
- Fuli Yang
- Department of Agriculture Biological Environment and Energy Engineering, Northeast Agriculture University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China
| | - Wenzhe Li
- Department of Agriculture Biological Environment and Energy Engineering, Northeast Agriculture University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China.
| | - Changyu Liu
- Department of Agriculture Biological Environment and Energy Engineering, Northeast Agriculture University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China; College of Architecture and Civil Engineering, Northeast Petroleum University, No. 199 Development Road, High-tech Development District, Daqing, 163318, China
| | - Mengyi Wang
- Department of Agriculture Biological Environment and Energy Engineering, Northeast Agriculture University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China
| | - Qiang Li
- Department of Agriculture Biological Environment and Energy Engineering, Northeast Agriculture University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China
| | - Yong Sun
- Department of Agriculture Biological Environment and Energy Engineering, Northeast Agriculture University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China
| |
Collapse
|
47
|
Rettenmaier R, Duerr C, Neuhaus K, Liebl W, Zverlov VV. Comparison of sampling techniques and different media for the enrichment and isolation of cellulolytic organisms from biogas fermenters. Syst Appl Microbiol 2019; 42:481-487. [DOI: 10.1016/j.syapm.2019.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/15/2019] [Accepted: 05/17/2019] [Indexed: 12/22/2022]
|
48
|
Yang Z, Wang W, Liu C, Zhang R, Liu G. Mitigation of ammonia inhibition through bioaugmentation with different microorganisms during anaerobic digestion: Selection of strains and reactor performance evaluation. WATER RESEARCH 2019; 155:214-224. [PMID: 30849735 DOI: 10.1016/j.watres.2019.02.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 02/21/2019] [Accepted: 02/22/2019] [Indexed: 05/20/2023]
Abstract
The effect of bioaugmentation with different microorganisms on anaerobic digestion to mitigate the ammonia inhibition problem was investigated. Seven pure strains of microorganisms (including obligate aceticlastic methanogen, facultative aceticlastic methanogen, hydrogenotrophic methanogen, syntrophic acetate oxidizing bacteria (SAOB) were selected and thirteen bioaugmentation approaches were tested. Bioaugmentation with hydrogenotrophic methanogen Methanobrevibacter smithii (MBS) and SAOB Syntrophaceticu schinkii together was the optimal choice, methane production (MP) was 71.1% higher than that in Blank, the activity of hydrogenotrophic methanogenesis was greatly heightened according to specific methanogenic activity analysis. Bioaugmentation with facultative aceticlastic methanogen Methanosarcina barkeri (MSB) alone without SAOB addition was also proven efficient (MP was 59.7% higher than that in Blank), both aceticlastic and hydrogenotrophic methanogenesis were enhanced. Further evaluation with carbon isotope fractionations analysis indicated that balancing the activities of the aceticlastic and hydrogenotrophic methanogenic pathways is of great importance. 16s rRNA gene sequencing results showed that Methanobacterium spp. and Methanosaeta spp. were the dominant archaea in all 14 reactors. Nevertheless, bioaugmentation with Methanosaeta spp. did not result in a positive effect on MP. On the other hand, Methanobrevibacter spp. and Methanosarcina spp. were non-dominant archaea (even after bioaugmentation with MBS or MSB, the relative abundances were still poor (<2%)), but displayed pivotal roles in determining the overall microbial consortium and, in turn, improved the overall performance.
Collapse
Affiliation(s)
- Ziyi Yang
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Wen Wang
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Chao Liu
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Ruihong Zhang
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing, 100029, China; Department of Biological & Agricultural Engineering, University of California, Davis, CA, 95616, USA
| | - Guangqing Liu
- Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing, 100029, China
| |
Collapse
|
49
|
Westerholm M, Dolfing J, Schnürer A. Growth Characteristics and Thermodynamics of Syntrophic Acetate Oxidizers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:5512-5520. [PMID: 30990997 DOI: 10.1021/acs.est.9b00288] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Syntrophic acetate oxidation (SAO) plays a pivotal role in biogas production processes when aceticlastic methanogens are inhibited. Despite the importance of SAO, the metabolic interactions and syntrophic growth of the organisms involved are still poorly understood. Therefore, we studied growth parameters and interactions within constructed defined cocultures comprising the methanogen Methanoculleus bourgensis and one, or several, of the syntrophic acetate oxidizers Syntrophaceticus schinkii, [ Clostridium] ultunense, and Tepidanaerobacter acetatoxydans and a novel, uncharacterized bacterium. Cultivation experiments in a design-of-experiment approach revealed positive effects on methane production rate of increased ammonium levels (up to 0.2 M), temperature (up to 45 °C), and acetate concentrations (0.15-0.30 M). Molecular analyses and thermodynamic calculations demonstrated close interlinkages between the microorganisms, with available energies of -10 kJ/mol for acetate oxidation and -20 kJ/mol for hydrogenotrophic methanogenesis. The estimated generation time varied between 3 and 20 days for all syntrophic microorganisms involved, and the acetate minimum threshold level was 0.40-0.45 mM. The rate of methanogenesis depended on the SAO bacteria present in the culture. These data are beneficial for interpretation of SAO prevalence and competiveness against aceticlastic methanogens in anaerobic environments.
Collapse
Affiliation(s)
- Maria Westerholm
- Department of Microbiology , Swedish University of Agricultural Sciences , Uppsala BioCenter, Box 7025, SE-750 07 Uppsala , Sweden
| | - Jan Dolfing
- School of Engineering , Newcastle University , Newcastle-upon-Tyne NE1 7RU United Kingdom
| | - Anna Schnürer
- Department of Microbiology , Swedish University of Agricultural Sciences , Uppsala BioCenter, Box 7025, SE-750 07 Uppsala , Sweden
| |
Collapse
|
50
|
Pore SD, Engineer A, Dagar SS, Dhakephalkar PK. Meta-omics based analyses of microbiome involved in biomethanation of rice straw in a thermophilic anaerobic bioreactor under optimized conditions. BIORESOURCE TECHNOLOGY 2019; 279:25-33. [PMID: 30710817 DOI: 10.1016/j.biortech.2019.01.099] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 06/09/2023]
Abstract
Biomethanation of rice straw was performed at 55 °C without thermochemical pretreatment using cattle dung supplemented with Methanothermobacter thermautotrophicus strains. Methane yield of 323 ml g-1 VS obtained under optimized conditions such as particle size (1 mm), carbon to nitrogen ratio (15:1), substrate to inoculum ratio (1:1), organic loading rate (7.5% w/v) and hydraulic retention time (20 days), was one of the highest ever reported from rice straw. Metagenome analysis revealed several putative novel taxa among resident microbes. The genomes of Clostridium, Hungateiclostridium, Alkaliphilus, Anaerocolumna, Olsenella, Paenibacillus, Pseudoclostridium, Tepidanaerobacter and Turicibacter were recovered as metagenome assisted genomes. Clostridium spp. and M. thermautotrophicus were the dominant hydrolytic and methanogenic microbes, respectively. Syntrophic acetate oxidation coupled to hydrogenotrophic methanogenesis was found to be the major pathway for methane production. Efficient thermophilic biomethanation of rice straw without thermochemical pretreatment using cattle dung supplemented with M. thermautotrophicus is reported for the first time.
Collapse
Affiliation(s)
- Soham D Pore
- Bioenergy Group, MACS Agharkar Research Institute, Pune 411004, Maharashtra, India; Savitribai Phule Pune University, Pune 411007, India
| | - Anupama Engineer
- Bioenergy Group, MACS Agharkar Research Institute, Pune 411004, Maharashtra, India
| | - Sumit Singh Dagar
- Bioenergy Group, MACS Agharkar Research Institute, Pune 411004, Maharashtra, India; Savitribai Phule Pune University, Pune 411007, India
| | - Prashant K Dhakephalkar
- Bioenergy Group, MACS Agharkar Research Institute, Pune 411004, Maharashtra, India; Savitribai Phule Pune University, Pune 411007, India.
| |
Collapse
|