DOCSLIB.ORG

Long-Term Experimental Warming Increases the Efficiency of the Methane Cycle

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Long-Term Experimental Warming Increases the Efficiency of the Methane Cycle Long-term experimental warming increases the efficiency of the methane cycle School of Biological and Chemical Sciences Queen Mary University of London Submitted in partial fulfilment of the requirements of the Degree of Doctor of Philosophy I, Yizhu Zhu, confirm that the research included within this thesis is my own work or that where it has been carried out in collaboration with, or supported by others, that this is duly acknowledged below and my contribution indicated. Previously published material is also acknowledged below. I attest that I have exercised reasonable care to ensure that the work is original, and does not to the best of my knowledge break any UK law, infringe any third party’s copyright or other Intellectual Property Right, or contain any confidential material. I accept that the College has the right to use plagiarism detection software to check the electronic version of the thesis. I confirm that this thesis has not been previously submitted for the award of a degree by this or any other university. The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author. Signature: Date: 27th September 2019 This research project was supervised by Professor Mark Trimmer and Dr. Kevin Purdy and was supported by Queen Mary Principal’s research studentship. Abstract Methane is a potent greenhouse gas whose net emission from ecosystems represents the balance between microbial methane production (methanogenesis) and oxidation (methanotrophy), each with different sensitivities to temperature. How this balance will be altered by global warming over the long-term, and especially in freshwaters that are major methane sources, remains unknown. Here I demonstrate, using a well-replicated (n=20), long- term (for 11 years) freshwater warming experiment (+4 °C above ambient), that experimental warming of freshwater ecosystems drives a disproportionate increase in methanogenesis over methanotrophy that increases the warming potential of the gases they emit. After 11 years of warming, an ongoing divergence in methane emission between the warmed and ambient ponds was revealed and the annual methane emissions are now 2.4-fold higher under warming, in far excess of predictions based on temperature alone. Such increase in methane emissions was augmented by shifts in the methanogen community as warming makes hydrogenotrophic methanogenesis more energetically favourable. In contrast, the methanotroph community was conserved. Methanotrophy was able to respond physiologically to higher temperatures and methane, though the overall capacity to oxidise methane was limited to < 95 % of the methane produced but not the 98 % required to prevent methane emission from increasing. This long-term warming experiment provides a mechanistic understanding of a potential positive feedback, where climate warming induces changes at microbial level that stimulate increases in whole-ecosystem methane emissions. Further, the experimentally induced changes to the methane cycle are borne out at global scale as a disproportionate increase in the capacity of naturally warmer ecosystems to emit methane. Together, the findings in this thesis strongly indicate that as Earth continues to warm, natural 1 ecosystems will emit disproportionately more methane to the atmosphere in a positive feedback warming loop. 2 Acknowledgements I would like to express my very great appreciation to my supervisor, Prof. Mark Trimmer, for giving me the opportunity to work on this project and for your guidance during the planning and development of this research work. Thank you for all the time you have been generously given for teaching me statistics, critical thinking and scientific writing. I would also like to thank Dr. Kevin Purdy, my co-supervisor, for useful suggestions and for patient instructions on molecular work and paper writing. Thanks to Dr. Ozge Eyice-Broadbent for teaching the molecular work and for sharing your experience in academia. Thanks to Dr. Liao Ouyang for introducing me the laboratory during my very first days in Queen Mary and to Dr. Lidong Shen and Dr. Sarah Harpenslager for very useful discussions on science. Thanks to Dr. Ian Sander, Dr. Felicity Shelley and Paul Fletcher for offering technical and fieldwork assistance. A big thank to Tian Du for your encouragement in the difficult times and for suggestions about surviving a PhD. And to my parents for your unconditional support throughout my study. 3 Table of Contents Abstract 1 Acknowledgements 3 Chapter 1 General Introduction ........................................................................... 8 1.1 Feedback through greater methane emissions in a warmer world ........................................ 8 1.1.1 Disproportionate emissions from freshwaters ..................................................................... 8 1.1.2 Temperature sensitivity of methane fluxes ......................................................................... 9 1.1.3 Methane emissions are not a simple response to temperature alone ................................. 10 1.2 Net CH4 emission: the balance between production (methanogenesis) and oxidation (methanotrophy) ............................................................................................................................................... 11 1.2.1 Methanogenesis and its response to warming ................................................................... 12 1.2.2 Methanotrophy responses to temperature and greater methane availability ..................... 13 1.2.3 Coupled processes between methane production and oxidation ....................................... 14 1.2.4 Long-term effects: can methanotrophy counterbalance methanogenesis in a warmer world? 15 1.3 Linking microbial communities to ecosystem-level processes .............................................. 16 1.3.1 Limitation in microbial community ecology ..................................................................... 17 1.3.2 Archaeal methanogens and bacterial methanotrophs ........................................................ 18 1.3.3 Temporal scales in linking microbial community to ecosystem-level processes .............. 19 1.3.4 A long-term warming mesocosm experiment ................................................................... 20 1.4 Goals and structural outline of the thesis ............................................................................... 21 Chapter 2 Long-term warming continuously amplifies methane emissions .. 23 2.1 Abstract ..................................................................................................................................... 23 2.2 Introduction .............................................................................................................................. 24 2.3 Materials and Methods ............................................................................................................ 26 2.3.1 Mesocosm pond facility .................................................................................................... 26 4 2.3.2 Sediment characteristics .................................................................................................... 26 2.3.3 Dissolved methane concentrations .................................................................................... 27 2.3.4 Methane and carbon dioxide fluxes measurements via high-frequency chambers ........... 28 2.3.5 Characterization of ebullition in methane emission measurements .................................. 29 2.3.6 Calculation of methane and carbon dioxide fluxes ........................................................... 31 2.3.7 Ratio of methane emission to net carbon dioxide exchange ............................................. 32 2.3.8 Net global warming potential of carbon gases emitted ..................................................... 33 2.3.9 Statistical analysis ............................................................................................................. 34 2.3.10 Prediction of methane emission from the apparent activation energy .............................. 39 2.4 Results........................................................................................................................................ 41 2.4.1 Sediment characteristics and comparison of CH4 emission from experimental ponds to natural ecosystems ......................................................................................................................................... 41 2.4.2 Net carbon dioxide exchange ............................................................................................ 42 2.4.3 Annual methane emissions ................................................................................................ 44 2.4.4 Ratio of methane emission to net carbon dioxide exchange ............................................. 46 2.4.5 Temperature dependence of methane and carbon dioxide emissions and rates of methane and carbon dioxide emissions at 15 °C .......................................................................................................... 50 2.4.6 Meta-analysis of global data on CH4 and CO2 emission at 15 °C ..................................... 53 2.4.7 Ratio of CH4 to CO2 emission ........................................................................................... 54 2.5 Discussion .................................................................................................................................
Load more

Recommended publications
  • Genotyping of Uncultured Archaea in a Polluted Site of Suez Gulf, Egypt, Based on 16S Rrna Gene Analyses
    Egyptian Journal of Aquatic Research (2014) 40,27–33 National Institute of Oceanography and Fisheries Egyptian Journal of Aquatic Research http://ees.elsevier.com/ejar www.sciencedirect.com FULL LENGTH ARTICLE Genotyping of uncultured archaea in a polluted site of Suez Gulf, Egypt, based on 16S rRNA gene analyses Hosam Easa Elsaied * Aquagenome Resources and Biotechnology Research Group, National Institute of Oceanography, 101-El-Kasr El-Eini Street, Cairo, Egypt Received 3 February 2014; revised 11 March 2014; accepted 11 March 2014 Available online 18 April 2014 KEYWORDS Abstract Culture-independent 16S rRNA gene analysis approach was used to explore and evalu- Archaea; ate archaea in a polluted site, El-Zeitia, Suez Gulf, Egypt. Metagenomic DNA was extracted from a 16S rRNA gene diversity; sediment sample. Archaeal 16S rRNA gene was PCR amplified using universal archaeal primers, Sediment; followed by cloning and direct analyses by sequencing. Rarefaction analysis showed saturation, Suez Gulf recording 21 archaeal 16S rRNA gene phylotypes, which represented the total composition of archaea in the studied sample. Phylogenetic analysis showed that all recorded phylotypes belonged to two archaeal phyla. Sixteen phylotypes were located in the branch of methanogenic Eur- yarchaeota and more closely related to species of the genera Methanosaeta and Methanomassiliicoc- cus. Five phylotypes were affiliated to the new archaeal phylum Thaumarchaeota, which represented by species Candidatus nitrosopumilus. The recorded phylotypes had unique sequences, characteriz- ing them as new phylogenetic lineages. This work is the first investigation of uncultured archaea in the Suez Gulf, and implicated that the environmental characteristics shaped the diversity of archa- eal 16S rRNA genes in the studied sample.
    [Show full text]
  • Research Article Diversity and Distribution of Archaea in the Mangrove Sediment of Sundarbans
    Hindawi Publishing Corporation Archaea Volume 2015, Article ID 968582, 14 pages http://dx.doi.org/10.1155/2015/968582 Research Article Diversity and Distribution of Archaea in the Mangrove Sediment of Sundarbans Anish Bhattacharyya,1 Niladri Shekhar Majumder,2 Pijush Basak,1 Shayantan Mukherji,3 Debojyoti Roy,1 Sudip Nag,1 Anwesha Haldar,4 Dhrubajyoti Chattopadhyay,1 Suparna Mitra,5 Maitree Bhattacharyya,1 and Abhrajyoti Ghosh3 1 Department of Biochemistry, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, West Bengal 700019, India 2RocheDiagnosticsIndiaPvt.Ltd.,Block4C,AkashTower,NearRubyHospital,781Anandapur,Kolkata700107,India 3Department of Biochemistry, Bose Institute, P1/12, C. I. T. Road, Scheme VIIM, Kolkata, West Bengal 700054, India 4Department of Geography, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, West Bengal 700019, India 5Norwich Medical School, University of East Anglia and Institute of Food Research, Norwich Research Park, Norwich, Norfolk NR4 7UA, UK Correspondence should be addressed to Dhrubajyoti Chattopadhyay; [email protected], Suparna Mitra; [email protected], Maitree Bhattacharyya; [email protected], and Abhrajyoti Ghosh; [email protected] Received 30 March 2015; Revised 25 June 2015; Accepted 14 July 2015 Academic Editor: William B. Whitman Copyright © 2015 Anish Bhattacharyya et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Mangroves are among the most diverse and productive coastal ecosystems in the tropical and subtropical regions. Environmental conditions particular to this biome make mangroves hotspots for microbial diversity, and the resident microbial communities play essential roles in maintenance of the ecosystem.
    [Show full text]
  • Insights Into Archaeal Evolution and Symbiosis from the Genomes of a Nanoarchaeon and Its Inferred Crenarchaeal Host from Obsidian Pool, Yellowstone National Park
    University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Microbiology Publications and Other Works Microbiology 4-22-2013 Insights into archaeal evolution and symbiosis from the genomes of a nanoarchaeon and its inferred crenarchaeal host from Obsidian Pool, Yellowstone National Park Mircea Podar University of Tennessee - Knoxville, [email protected] Kira S. Makarova National Institutes of Health David E. Graham University of Tennessee - Knoxville, [email protected] Yuri I. Wolf National Institutes of Health Eugene V. Koonin National Institutes of Health See next page for additional authors Follow this and additional works at: https://trace.tennessee.edu/utk_micrpubs Part of the Microbiology Commons Recommended Citation Biology Direct 2013, 8:9 doi:10.1186/1745-6150-8-9 This Article is brought to you for free and open access by the Microbiology at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Microbiology Publications and Other Works by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. Authors Mircea Podar, Kira S. Makarova, David E. Graham, Yuri I. Wolf, Eugene V. Koonin, and Anna-Louise Reysenbach This article is available at TRACE: Tennessee Research and Creative Exchange: https://trace.tennessee.edu/ utk_micrpubs/44 Podar et al. Biology Direct 2013, 8:9 http://www.biology-direct.com/content/8/1/9 RESEARCH Open Access Insights into archaeal evolution and symbiosis from the genomes of a nanoarchaeon and its inferred crenarchaeal host from Obsidian Pool, Yellowstone National Park Mircea Podar1,2*, Kira S Makarova3, David E Graham1,2, Yuri I Wolf3, Eugene V Koonin3 and Anna-Louise Reysenbach4 Abstract Background: A single cultured marine organism, Nanoarchaeum equitans, represents the Nanoarchaeota branch of symbiotic Archaea, with a highly reduced genome and unusual features such as multiple split genes.
    [Show full text]
  • Nitrate Decreases Ruminal Methane Production with Slight Changes To
    Zhao et al. BMC Microbiology (2018) 18:21 https://doi.org/10.1186/s12866-018-1164-1 RESEARCH ARTICLE Open Access Nitrate decreases ruminal methane production with slight changes to ruminal methanogen composition of nitrate- adapted steers Liping Zhao, Qingxiang Meng, Yan Li, Hao Wu, Yunlong Huo, Xinzhuang Zhang and Zhenming Zhou* Abstract Background: This study was conducted to examine effects of nitrate on ruminal methane production, methanogen abundance, and composition. Six rumen-fistulated Limousin×Jinnan steers were fed diets supplemented with either 0% (0NR), 1% (1NR), or 2% (2NR) nitrate (dry matter basis) regimens in succession. Rumen fluid was taken after two-week adaptation for evaluation of in vitro methane production, methanogen abundance, and composition measurements. Results: Results showed that nitrate significantly decreased in vitro ruminal methane production at 6 h, 12 h, and 24 h (P < 0.01; P < 0.01; P = 0.01). The 1NR and 2NR regimens numerically reduced the methanogen population by 4.47% and 25.82% respectively. However, there was no significant difference observed between treatments. The alpha and beta diversity of the methanogen community was not significantly changed by nitrate either. However, the relative abundance of the methanogen genera was greatly changed. Methanosphaera (PL = 0.0033) and Methanimicrococcus (PL = 0.0113) abundance increased linearly commensurate with increasing nitration levels, while Methanoplanus abundance was significantly decreased (PL = 0.0013). The population of Methanoculleus, the least frequently identified genus in this study, exhibited quadratic growth from 0% to 2% when nitrate was added (PQ = 0.0140). Conclusions: Correlation analysis found that methane reduction was significantly related to Methanobrevibacter and Methanoplanus abundance, and negatively correlated with Methanosphaera and Methanimicrococcus abundance.
    [Show full text]
  • Diversity of Archaea Domain in Cuatro Cienegas Basin: Archaean Domes
    bioRxiv preprint doi: https://doi.org/10.1101/766709; this version posted September 12, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 Diversity of Archaea Domain in Cuatro Cienegas Basin: Archaean Domes 2 3 Medina-Chávez Nahui Olin1, Viladomat-Jasso Mariette2, Olmedo-Álvarez Gabriela3, Eguiarte Luis 4 E2, Souza Valeria2, De la Torre-Zavala Susana1,4 5 6 1Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Instituto de 7 Biotecnología. Av. Pedro de Alba S/N Ciudad Universitaria. San Nicolás de los Garza, Nuevo León, 8 México. C.P. 66455. 9 2Instituto de Ecología, UNAM, Circuito Exterior S/N anexo Jardín Botánico exterior. Ciudad 10 Universitaria, Ciudad de México, C.P. 04500 11 3Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del I.P.N. 12 Campus Guanajuato, AP 629 Irapuato, Guanajuato 36500, México 13 14 4Correspondence should be addressed to Susana De la Torre-Zavala; 15 [email protected]. 16 17 18 19 20 21 22 1 bioRxiv preprint doi: https://doi.org/10.1101/766709; this version posted September 12, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 23 Abstract 24 Herein we describe the Archaea diversity in a shallow pond in the Cuatro Ciénegas Basin (CCB), 25 Northeast Mexico, with fluctuating hypersaline conditions containing elastic microbial mats that 26 can form small domes where their anoxic inside reminds us of the characteristics of the Archaean 27 Eon, rich in methane and sulfur gases; thus, we named this site the Archaean Domes (AD).
    [Show full text]
  • The Genome Sequence of Methanohalophilus Mahii SLPT
    Hindawi Publishing Corporation Archaea Volume 2010, Article ID 690737, 16 pages doi:10.1155/2010/690737 Research Article TheGenomeSequenceofMethanohalophilus mahii SLPT Reveals Differences in the Energy Metabolism among Members of the Methanosarcinaceae Inhabiting Freshwater and Saline Environments Stefan Spring,1 Carmen Scheuner,1 Alla Lapidus,2 Susan Lucas,2 Tijana Glavina Del Rio,2 Hope Tice,2 Alex Copeland,2 Jan-Fang Cheng,2 Feng Chen,2 Matt Nolan,2 Elizabeth Saunders,2, 3 Sam Pitluck,2 Konstantinos Liolios,2 Natalia Ivanova,2 Konstantinos Mavromatis,2 Athanasios Lykidis,2 Amrita Pati,2 Amy Chen,4 Krishna Palaniappan,4 Miriam Land,2, 5 Loren Hauser,2, 5 Yun-Juan Chang,2, 5 Cynthia D. Jeffries,2, 5 Lynne Goodwin,2, 3 John C. Detter,3 Thomas Brettin,3 Manfred Rohde,6 Markus Goker,¨ 1 Tanja Woyke, 2 Jim Bristow,2 Jonathan A. Eisen,2, 7 Victor Markowitz,4 Philip Hugenholtz,2 Nikos C. Kyrpides,2 and Hans-Peter Klenk1 1 DSMZ—German Collection of Microorganisms and Cell Cultures GmbH, 38124 Braunschweig, Germany 2 DOE Joint Genome Institute, Walnut Creek, CA 94598-1632, USA 3 Los Alamos National Laboratory, Bioscience Division, Los Alamos, NM 87545-001, USA 4 Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA 5 Oak Ridge National Laboratory, Oak Ridge, TN 37830-8026, USA 6 HZI—Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany 7 Davis Genome Center, University of California, Davis, CA 95817, USA Correspondence should be addressed to Stefan Spring, [email protected] and Hans-Peter Klenk, [email protected] Received 24 August 2010; Accepted 9 November 2010 Academic Editor: Valerie´ de Crecy-Lagard´ Copyright © 2010 Stefan Spring et al.
    [Show full text]
  • Variations in the Two Last Steps of the Purine Biosynthetic Pathway in Prokaryotes
    GBE Different Ways of Doing the Same: Variations in the Two Last Steps of the Purine Biosynthetic Pathway in Prokaryotes Dennifier Costa Brandao~ Cruz1, Lenon Lima Santana1, Alexandre Siqueira Guedes2, Jorge Teodoro de Souza3,*, and Phellippe Arthur Santos Marbach1,* 1CCAAB, Biological Sciences, Recoˆ ncavo da Bahia Federal University, Cruz das Almas, Bahia, Brazil 2Agronomy School, Federal University of Goias, Goiania,^ Goias, Brazil 3 Department of Phytopathology, Federal University of Lavras, Minas Gerais, Brazil Downloaded from https://academic.oup.com/gbe/article/11/4/1235/5345563 by guest on 27 September 2021 *Corresponding authors: E-mails: [email protected]fla.br; [email protected]. Accepted: February 16, 2019 Abstract The last two steps of the purine biosynthetic pathway may be catalyzed by different enzymes in prokaryotes. The genes that encode these enzymes include homologs of purH, purP, purO and those encoding the AICARFT and IMPCH domains of PurH, here named purV and purJ, respectively. In Bacteria, these reactions are mainly catalyzed by the domains AICARFT and IMPCH of PurH. In Archaea, these reactions may be carried out by PurH and also by PurP and PurO, both considered signatures of this domain and analogous to the AICARFT and IMPCH domains of PurH, respectively. These genes were searched for in 1,403 completely sequenced prokaryotic genomes publicly available. Our analyses revealed taxonomic patterns for the distribution of these genes and anticorrelations in their occurrence. The analyses of bacterial genomes revealed the existence of genes coding for PurV, PurJ, and PurO, which may no longer be considered signatures of the domain Archaea. Although highly divergent, the PurOs of Archaea and Bacteria show a high level of conservation in the amino acids of the active sites of the protein, allowing us to infer that these enzymes are analogs.
    [Show full text]
  • Nov., Isolated from an Oil-Producing Well
    International Journal of Systematic Bacteriology (1998), 48, 821-828 Printed in Great Britain Methanocalculus halotolerans gen. nov., sp. nov., isolated from an oil-producing well Bernard Ollivier,’ Marie-Laure Fardeau,l Jean-Luc Cayol,’ Michel Magot,’ Bharat K. C. Patel,3 Gerard Prensiep and Jean-Louis Garcia’ Author for correspondence: Bernard Ollivier. Tel: + 33 4 91 82 85 76. Fax: + 33 4 91 82 85 70. e-mail : [email protected] 1 Laboratoire ORSTOM de Two irregular coccoid methanogens designated SEBR 4845Tand FRlT were Microbiologie des isolated from an oilfield in Alsace, France. Strain SEBR 4845l (T = type strain) is AnaCrobies, UniversitC de Provence, 13288 Marseille a hydrogenotrophic halotolerant methanogen, which grows optimally at 5 O/O Cedex 9, France NaCl (whr) and tolerates up to 12O/0 NaCI. It does not use methylated * Sanofi Recherche, Groupe compounds and therefore cannot be ascribed to any of the known genera of Elf-Aquitaine, Unit6 de the halophilic methylotrophic methanogens. It differs from hydrogenotrophic Microbiologie, 31 676 members of the orders Methanococcales and Methanomicrobiales in the NaCl La b&ge Cedex, France growth range (0-12% NaCI), which is the widest reported to date for any 3 School of Biomolecular hydrogenotrophic methanogen. 165 rRNA gene sequence analysis indicated and Biomedical Sciences, Griffith University, Nathan that strain SEBR 4845l is a novel isolate for which a new genus is proposed, 41 11, Brisbane, Methanocalculus halotolerans gen. nov., sp. nov. (= OCM 4703 that might be Queensland, Australia indigenous to the oilfield ecosystem. Strain FRlT (= OCM 471) is a moderately 4 Laboratoire de halophilic methanogen which grows optimally at 10% NaCl and tolerates up to Microbiologie, UniversitC 20% NaCI.
    [Show full text]
  • Thermophiles and Thermozymes
    Thermophiles and Thermozymes Edited by María-Isabel González-Siso Printed Edition of the Special Issue Published in Microorganisms www.mdpi.com/journal/microorganisms Thermophiles and Thermozymes Thermophiles and Thermozymes Special Issue Editor Mar´ıa-Isabel Gonz´alez-Siso MDPI • Basel • Beijing • Wuhan • Barcelona • Belgrade Special Issue Editor Mar´ıa-Isabel Gonzalez-Siso´ Universidade da Coruna˜ Spain Editorial Office MDPI St. Alban-Anlage 66 4052 Basel, Switzerland This is a reprint of articles from the Special Issue published online in the open access journal Microorganisms (ISSN 2076-2607) from 2018 to 2019 (available at: https://www.mdpi.com/journal/ microorganisms/special issues/thermophiles) For citation purposes, cite each article independently as indicated on the article page online and as indicated below: LastName, A.A.; LastName, B.B.; LastName, C.C. Article Title. Journal Name Year, Article Number, Page Range. ISBN 978-3-03897-816-9 (Pbk) ISBN 978-3-03897-817-6 (PDF) c 2019 by the authors. Articles in this book are Open Access and distributed under the Creative Commons Attribution (CC BY) license, which allows users to download, copy and build upon published articles, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. The book as a whole is distributed by MDPI under the terms and conditions of the Creative Commons license CC BY-NC-ND. Contents About the Special Issue Editor ...................................... vii Mar´ıa-Isabel Gonz´alez-Siso Editorial for the Special Issue: Thermophiles and Thermozymes Reprinted from: Microorganisms 2019, 7, 62, doi:10.3390/microorganisms7030062 ........
    [Show full text]
  • Methanogens: Biochemical Background and Biotechnological Applications Franziska Enzmann1, Florian Mayer1 , Michael Rother2 and Dirk Holtmann1*
    Enzmann et al. AMB Expr (2018) 8:1 https://doi.org/10.1186/s13568-017-0531-x MINI-REVIEW Open Access Methanogens: biochemical background and biotechnological applications Franziska Enzmann1, Florian Mayer1 , Michael Rother2 and Dirk Holtmann1* Abstract Since fossil sources for fuel and platform chemicals will become limited in the near future, it is important to develop new concepts for energy supply and production of basic reagents for chemical industry. One alternative to crude oil and fossil natural gas could be the biological conversion of ­CO2 or small organic molecules to methane via metha‑ nogenic archaea. This process has been known from biogas plants, but recently, new insights into the methanogenic metabolism, technical optimizations and new technology combinations were gained, which would allow moving beyond the mere conversion of biomass. In biogas plants, steps have been undertaken to increase yield and purity of the biogas, such as addition of hydrogen or metal granulate. Furthermore, the integration of electrodes led to the development of microbial electrosynthesis (MES). The idea behind this technique is to use CO­ 2 and electrical power to generate methane via the microbial metabolism. This review summarizes the biochemical and metabolic background of methanogenesis as well as the latest technical applications of methanogens. As a result, it shall give a sufcient overview over the topic to both, biologists and engineers handling biological or bioelectrochemical methanogenesis. Keywords: Methanogens, Genetic tools, Biogas, Microbial electrosynthesis, Electroactivity Introduction process involving methanogens. Tese archaea use CO­ 2 Methanogens are biocatalysts, which have the potential and ­H2 and/or small organic molecules, such as acetate, to contribute to a solution for future energy problems by formate, and methylamine and convert it to methane.
    [Show full text]
  • International Code of Nomenclature of Prokaryotes
    2019, volume 69, issue 1A, pages S1–S111 International Code of Nomenclature of Prokaryotes Prokaryotic Code (2008 Revision) Charles T. Parker1, Brian J. Tindall2 and George M. Garrity3 (Editors) 1NamesforLife, LLC (East Lansing, Michigan, United States) 2Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH (Braunschweig, Germany) 3Michigan State University (East Lansing, Michigan, United States) Corresponding Author: George M. Garrity ([email protected]) Table of Contents 1. Foreword to the First Edition S1–S1 2. Preface to the First Edition S2–S2 3. Preface to the 1975 Edition S3–S4 4. Preface to the 1990 Edition S5–S6 5. Preface to the Current Edition S7–S8 6. Memorial to Professor R. E. Buchanan S9–S12 7. Chapter 1. General Considerations S13–S14 8. Chapter 2. Principles S15–S16 9. Chapter 3. Rules of Nomenclature with Recommendations S17–S40 10. Chapter 4. Advisory Notes S41–S42 11. References S43–S44 12. Appendix 1. Codes of Nomenclature S45–S48 13. Appendix 2. Approved Lists of Bacterial Names S49–S49 14. Appendix 3. Published Sources for Names of Prokaryotic, Algal, Protozoal, Fungal, and Viral Taxa S50–S51 15. Appendix 4. Conserved and Rejected Names of Prokaryotic Taxa S52–S57 16. Appendix 5. Opinions Relating to the Nomenclature of Prokaryotes S58–S77 17. Appendix 6. Published Sources for Recommended Minimal Descriptions S78–S78 18. Appendix 7. Publication of a New Name S79–S80 19. Appendix 8. Preparation of a Request for an Opinion S81–S81 20. Appendix 9. Orthography S82–S89 21. Appendix 10. Infrasubspecific Subdivisions S90–S91 22. Appendix 11. The Provisional Status of Candidatus S92–S93 23.
    [Show full text]
  • Enrichment and Diversity Analysis of the Thermophilic Microbes in a High Temperature Petroleum Reservoir
    African Journal of Microbiology Research Vol. 5(14), pp. 1850-1857, 18 July, 2011 Available online http://www.academicjournals.org/ajmr DOI: 10.5897/AJMR11.354 ISSN 1996-0808 ©2011 Academic Journals Full Length Research Paper Enrichment and diversity analysis of the thermophilic microbes in a high temperature petroleum reservoir Guihong Lan1,2, Zengting Li1, Hui zhang3, Changjun Zou2, Dairong Qiao1 and Yi Cao1* 1School of Life Science, Sichuan University, Chengdu 610065, China. 2School of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China. 3Biogas Institute of Ministry of Agriculture P. R. China, Chengdu 610041, China. Accepted 1 June, 2011 Thermophilic microbial diversity in production water from a high temperature, water-flooded petroleum reservoir of an offshore oilfield in China was characterized by enrichment and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. Six different function enrichment cultures were cultivated one year, at 75°C DGGE and sequence analyses of 16S rRNA gene fragments were used to assess the thermophilic microbial diversity. A total of 27 bacterial and 9 archaeal DGGE bands were excised and sequenced. Phylogenetic analysis of these sequences indicated that 21 bacterial and 7 archaeal phylotypes were affiliated with thermophilic microbe. The bacterial sequences were mainly bonged to the genera Fervidobacterium, Thermotoga, Dictyoglomus, Symbiobacterium, Moorella, Thermoanaerobacter, Desulfotomaculum, Thermosyntropha, Coprothermobacter, Caloramator, Thermacetogenium, and the archaeal phylogypes were represented in the genera Geoglobus and Thermococcus, Methanomethylovorans, Methanothermobacter Methanoculleus and Methanosaeta. So many thermophiles were detected suggesting that they might be common habitants in high-temperature petroleum reservoirs. The results of this work provide further insight into the thermophilic composition of microbial communities in high temperature petroleum reservoirs.
    [Show full text]