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Peña-Salinas ME, Speth DR, Utter DR, Spelz RM, Lim S, Zierenberg R, Caress DW, Núñez PG, Vázquez R, Orphan VJ. Thermotogota diversity and distribution patterns revealed in Auka and JaichMaa 'ja 'ag hydrothermal vent fields in the Pescadero Basin, Gulf of California. PeerJ 2024; 12:e17724. [PMID: 39175749 PMCID: PMC11340630 DOI: 10.7717/peerj.17724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 06/20/2024] [Indexed: 08/24/2024] Open
Abstract
Discovering new deep hydrothermal vent systems is one of the biggest challenges in ocean exploration. They are a unique window to elucidate the physical, geochemical, and biological processes that occur on the seafloor and are involved in the evolution of life on Earth. In this study, we present a molecular analysis of the microbial composition within the newly discovered hydrothermal vent field, JaichMaa 'ja 'ag, situated in the Southern Pescadero Basin within the Gulf of California. During the cruise expedition FK181031 in 2018, 33 sediment cores were collected from various sites within the Pescadero vent fields and processed for 16S rRNA amplicon sequence variants (ASVs) and geochemical analysis. Correlative analysis of the chemical composition of hydrothermal pore fluids and microbial abundances identified several sediment-associated phyla, including Thermotogota, that appear to be enriched in sediment horizons impacted by hydrothermal fluid flow. Comparative analysis of Thermotogota with the previously explored Auka hydrothermal vent field situated 2 km away displayed broad similarity between the two locations, although at finer scales (e.g., ASV level), there were notable differences that point to core-to-core and site-level factors revealing distinct patterns of distribution and abundance within these two sediment-hosted hydrothermal vent fields. These patterns are intricately linked to the specific physical and geochemical conditions defining each vent, illuminating the complexity of this unique deep ocean chemosynthetic ecosystem.
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Affiliation(s)
- Manet E. Peña-Salinas
- Facultad de Ciencias Marinas, Universidad Autónoma de Baja California, Ensenada, Baja California, Mexico
- Laboratorio de Astrobiología, Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, Baja California, Mexico
| | - Daan R. Speth
- Division of Microbial Ecology, Center for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California, United States
| | - Daniel R. Utter
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California, United States
| | - Ronald M. Spelz
- Facultad de Ciencias Marinas, Universidad Autónoma de Baja California, Ensenada, Baja California, Mexico
| | - Sujung Lim
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California, United States
| | - Robert Zierenberg
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, United States
| | - David W. Caress
- Science Division, Monterey Bay Aquarium Research Institute, Moss Landing, California, United States
| | - Patricia G. Núñez
- Laboratorio de Astrobiología, Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, Baja California, Mexico
| | - Roberto Vázquez
- Laboratorio de Astrobiología, Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, Baja California, Mexico
| | - Victoria J. Orphan
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California, United States
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2
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Rowe L, Dowd SE, Davidson K, Kovarik C, VanAken M, Jarabek A, Taylor C. Comparing microbial populations from diverse hydrothermal features in Yellowstone National Park: hot springs and mud volcanoes. Front Microbiol 2024; 15:1409664. [PMID: 38993494 PMCID: PMC11236564 DOI: 10.3389/fmicb.2024.1409664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Accepted: 05/30/2024] [Indexed: 07/13/2024] Open
Abstract
Geothermal features, such as hot springs and mud volcanoes, host diverse microbial life, including many extremophile organisms. The physicochemical parameters of the geothermal feature, such as temperature, pH, and heavy metal concentration, can influence the alpha and beta diversity of microbial life in these environments, as can spatiotemporal differences between sites and sampling. In this study, water and sediment samples were collected and analyzed from eight geothermal sites at Yellowstone National Park, including six hot springs, a mud volcano, and an acidic lake within the same week in July 2019, and these geothermal sites varied greatly in their temperature, pH, and chemical composition. All samples were processed and analyzed with the same methodology and taxonomic profiles and alpha and beta diversity metrics determined with 16S rRNA sequencing. These microbial diversity results were then analyzed with respect to pH, temperature, and chemical composition of the geothermal features. Results indicated that predominant microbial species varied greatly depending on the physicochemical composition of the geothermal site, with decreases in pH and increases in dissolved heavy metals in the water corresponding to decreases in alpha diversity, especially in the sediment samples. Similarly, sites with acidic pH values had more similar microbial populations (beta diversity) to one another than to relatively neutral or alkaline pH geothermal sites. This study suggests that pH and/or heavy metal concentration is a more important driver for microbial diversity and population profile than the temperature for these sites and is also the first reported microbial diversity study for multiple geothermal sites in Yellowstone National Park, including the relatively new mud volcano Black Dragon's Caldron, which erupted in 1948.
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Affiliation(s)
- Laura Rowe
- Department of Chemistry, Eastern Kentucky University, Richmond, KY, United States
- Department of Chemistry, Valparaiso University, Valparaiso, IN, United States
| | - Scot E. Dowd
- Molecular Research LP (MR DNA Lab), Shallowater, TX, United States
| | - Kelly Davidson
- Department of Chemistry, Valparaiso University, Valparaiso, IN, United States
| | - Claire Kovarik
- Department of Chemistry, Valparaiso University, Valparaiso, IN, United States
| | - Michayla VanAken
- Department of Chemistry, Valparaiso University, Valparaiso, IN, United States
| | - Alyssa Jarabek
- Department of Chemistry, Valparaiso University, Valparaiso, IN, United States
| | - Churro Taylor
- Department of Chemistry, Eastern Kentucky University, Richmond, KY, United States
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3
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Burkhardt C, Baruth L, Neele Meyer-Heydecke, Klippel B, Margaryan A, Paloyan A, Panosyan HH, Antranikian G. Mining thermophiles for biotechnologically relevant enzymes: evaluating the potential of European and Caucasian hot springs. Extremophiles 2023; 28:5. [PMID: 37991546 PMCID: PMC10665251 DOI: 10.1007/s00792-023-01321-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 10/06/2023] [Indexed: 11/23/2023]
Abstract
The development of sustainable and environmentally friendly industrial processes is becoming very crucial and demanding for the rapid implementation of innovative bio-based technologies. Natural extreme environments harbor the potential for discovering and utilizing highly specific and efficient biocatalysts that are adapted to harsh conditions. This review focuses on extremophilic microorganisms and their enzymes (extremozymes) from various hot springs, shallow marine vents, and other geothermal habitats in Europe and the Caucasus region. These hot environments have been partially investigated and analyzed for microbial diversity and enzymology. Hotspots like Iceland, Italy, and the Azores harbor unique microorganisms, including bacteria and archaea. The latest results demonstrate a great potential for the discovery of new microbial species and unique enzymes that can be explored for the development of Circular Bioeconomy.Different screening approaches have been used to discover enzymes that are active at extremes of temperature (up 120 °C), pH (0.1 to 11), high salt concentration (up to 30%) as well as activity in the presence of solvents (up to 99%). The majority of published enzymes were revealed from bacterial or archaeal isolates by traditional activity-based screening techniques. However, the latest developments in molecular biology, bioinformatics, and genomics have revolutionized life science technologies. Post-genomic era has contributed to the discovery of millions of sequences coding for a huge number of biocatalysts. Both strategies, activity- and sequence-based screening approaches, are complementary and contribute to the discovery of unique enzymes that have not been extensively utilized so far.
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Affiliation(s)
- Christin Burkhardt
- Institute of Technical Biocatalysis, Center for Biobased Solutions, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073, Hamburg, Germany
| | - Leon Baruth
- Institute of Technical Biocatalysis, Center for Biobased Solutions, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073, Hamburg, Germany
| | - Neele Meyer-Heydecke
- Institute of Technical Biocatalysis, Center for Biobased Solutions, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073, Hamburg, Germany
| | - Barbara Klippel
- Institute of Technical Biocatalysis, Center for Biobased Solutions, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073, Hamburg, Germany
| | - Armine Margaryan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, Alex Manoogian 1, 0025, Yerevan, Armenia
- Research Institute of Biology, Yerevan State University, Alex Manoogian 1, 0025, Yerevan, Armenia
| | - Ani Paloyan
- Scientific and Production Center, "Armbiotechnology" NAS RA, 14 Gyurjyan Str. 0056, Yerevan, Armenia
| | - Hovik H Panosyan
- Department of Biochemistry, Microbiology and Biotechnology, Yerevan State University, Alex Manoogian 1, 0025, Yerevan, Armenia
- Research Institute of Biology, Yerevan State University, Alex Manoogian 1, 0025, Yerevan, Armenia
| | - Garabed Antranikian
- Institute of Technical Biocatalysis, Center for Biobased Solutions, Hamburg University of Technology, Am Schwarzenberg-Campus 4, 21073, Hamburg, Germany.
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4
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Sexton D, Hashimi A, Beskrovnaya P, Sibanda L, Huan T, Tocheva E. The cell envelope of Thermotogae suggests a mechanism for outer membrane biogenesis. Proc Natl Acad Sci U S A 2023; 120:e2303275120. [PMID: 37094164 PMCID: PMC10160955 DOI: 10.1073/pnas.2303275120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 03/29/2023] [Indexed: 04/26/2023] Open
Abstract
The presence of a cell membrane is one of the major structural components defining life. Recent phylogenomic analyses have supported the hypothesis that the last universal common ancestor (LUCA) was likely a diderm. Yet, the mechanisms that guided outer membrane (OM) biogenesis remain unknown. Thermotogae is an early-branching phylum with a unique OM, the toga. Here, we use cryo-electron tomography to characterize the in situ cell envelope architecture of Thermotoga maritima and show that the toga is made of extended sheaths of β-barrel trimers supporting small (~200 nm) membrane patches. Lipidomic analyses identified the same major lipid species in the inner membrane (IM) and toga, including the rare to bacteria membrane-spanning ether-bound diabolic acids (DAs). Proteomic analyses revealed that the toga was composed of multiple SLH-domain containing Ompα and novel β-barrel proteins, and homology searches detected variable conservations of these proteins across the phylum. These results highlight that, in contrast to the SlpA/OmpM superfamily of proteins, Thermotoga possess a highly diverse bipartite OM-tethering system. We discuss the implications of our findings with respect to other early-branching phyla and propose that a toga-like intermediate may have facilitated monoderm-to-diderm cell envelope transitions.
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Affiliation(s)
- Danielle L. Sexton
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, Vancouver,V6T1Z3 BC, Canada
| | - Ameena Hashimi
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, Vancouver,V6T1Z3 BC, Canada
| | - Polina Beskrovnaya
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, Vancouver,V6T1Z3 BC, Canada
| | - Lloyd Sibanda
- Department of Chemistry, University of British Columbia, Vancouver,V6T1Z1 BC, Canada
| | - Tao Huan
- Department of Chemistry, University of British Columbia, Vancouver,V6T1Z1 BC, Canada
| | - Elitza I. Tocheva
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, Vancouver,V6T1Z3 BC, Canada
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Fervidobacterium pennivorans subsp. keratinolyticus subsp. nov., a Novel Feather-Degrading Anaerobic Thermophile. Microorganisms 2022; 11:microorganisms11010022. [PMID: 36677314 PMCID: PMC9861569 DOI: 10.3390/microorganisms11010022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/09/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
Fervidobacterium pennivorans subsp. keratinolyticus subsp. nov. strain T was isolated from a terrestrial, high-altitude hot spring in Tajikistan. This strain is an obligate anaerobic rod and their cells occur singly, in pairs, or as short chains under the optimal growth conditions of a temperature of 65 °C and pH 6.5, with peptone, glucose, and galactose as the preferred substrates. The minimum generation time of this strain is 150 min. Strain T can efficiently degrade feather keratin at 65-75 °C; this unusual feature is also exhibited by a few other members of the Fervidobacterium genus. The total genome size of this bacterial strain is 2,002,515 base pairs, with a C + G content of 39.0%. The maximum digital DNA-DNA hybridization (dDDH) value of 76.9% was observed on comparing the genome of this strain with that of Fervidobacterium pennivorans type strain DSM9078. This study describes the physiological and genomic properties of strain T, with an emphasis on its keratinolytic power and differences from other members of the genus Fervidobacterium.
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Zhang S, Xiao M, Liang C, Chui C, Wang N, Shi J, Liu L. Multivariate insights into enhanced biogas production in thermophilic dry anaerobic co-digestion of food waste with kitchen waste or garden waste: Process properties, microbial communities and metagenomic analyses. BIORESOURCE TECHNOLOGY 2022; 361:127684. [PMID: 35882315 DOI: 10.1016/j.biortech.2022.127684] [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: 05/27/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
Multisubstrate synergetic anaerobic co-digestion can effectively overcome low efficiency of food waste (FW) mono-digestion. This study investigated the effect of supplementing FW with kitchen waste (KW) or garden waste (GW) on thermophilic dry anaerobic co-digestion. FW-KW and FW-GW co-digestion enhanced biogas production by 24.69 % and 44.96 % at organic loading rate (OLR) of 3 g VS L-1 d-1, and increased OLR tolerance from 3 to 4 g VS L-1 d-1 through mitigating ammonia nitrogen inhibition and volatile fatty acids accumulation. Co-digestion enriched the dominant hydrolytic bacteria Defluviitoga, resulting in an acceleration of substrate hydrolysis. FW-KW co-digestion improved biogas production by increasing gene abundance related to key enzymes in methanogenesis pathways and promoting the conversion of intermediate products into methane. FW-GW co-digestion enhanced biogas production by enriching ABC transporters-associated genes, leading to efficient substrate utilization. This study provides a promising approach for FW treatment with multivariate insights into thermophilic dry anaerobic co-digestion.
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Affiliation(s)
- Siying Zhang
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mengyao Xiao
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chengyu Liang
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunmeng Chui
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
| | - Na Wang
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiping Shi
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; University of Chinese Academy of Sciences, Beijing 100049, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Li Liu
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Shanghai 200241, China.
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7
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Zhou H, Xing D, Ma J, Su Y, Zhang Y. Electrifying anaerobic granular sludge for enhanced waste anaerobic digestion and biogas production. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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Haroun B, Bahreini G, Zaman M, Jang E, Okoye F, Elbeshbishy E, Santoro D, Walton J, Al-Omari A, Muller C, Bell K, Nakhla G. Vacuum-enhanced anaerobic fermentation: Achieving process intensification, thickening and improved hydrolysis and VFA yields in a single treatment step. WATER RESEARCH 2022; 220:118719. [PMID: 35704979 DOI: 10.1016/j.watres.2022.118719] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/08/2022] [Accepted: 06/04/2022] [Indexed: 06/15/2023]
Abstract
This study assessed the feasibility of a novel vacuum-enhanced anaerobic digestion technology, referred to as IntensiCarbTM (IC), under mild vacuum pressure (110 mbar), compared to a control (conventional fermenter), and evaluated the impact of the vacuum on the activities of various microbial groups. Both fermenters (test and control) were operated with mixed (50% v/v) municipal sludge at solids concentrations of 2-2.5%, pH of 7.8-8.1, 40-45 °C, a theoretical solids retention time (SRT) of 3 days with different hydraulic retention times (HRT). The intensification factor (IF) of the IC, defined as SRT/HRT, was controlled at 1.3 and 2.0. Simultaneous thickening and fermentation intensification were achieved. Compared with the control, the IC, despite the shorter HRTs, achieved 29.5 to 90.2% increase in the VFA yield (79 to 116 mg ΔVFA/ g VSS vs 61 mg ΔVFA/ g VSS), and 16.2% to 56.4% increase (280 to 377 mg ΔsCOD/ g VSS vs 241 mg ΔsCOD/ g VSS), in the hydrolysis yield. Fermentate from the IC exhibited comparable specific denitrification rates to acetate. Further, the solids-free condensate contained low nutrient concentrations, and thus was far superior to a typical centrates from dewatering as a carbon source. No adverse effects of vacuum on the activity of fermentative bacteria and methanogens were observed. This study demonstrated that the IC can be deployed as an intensification technology for both fermentation and anaerobic digestion of biosolids with the additional significant advantage, i.e. elimination of sidestream ammonia treatment requirements.
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Affiliation(s)
- Basem Haroun
- Chemical and Biochemical Engineering, University of Western Ontario, Canada; Water Pollution Research Department, National Research Center, 33 El Bohoth St., P.O.12622, Dokki, Giza, Egypt
| | | | - Masuduz Zaman
- Chemical and Biochemical Engineering, University of Western Ontario, Canada
| | | | - Frances Okoye
- Civil Engineering Department, Ryerson University, Canada
| | | | | | | | | | | | | | - George Nakhla
- Chemical and Biochemical Engineering, University of Western Ontario, Canada; Civil and Environmental Engineering, University of Western Ontario, Canada.
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9
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Dudek CA, Jahn D. PRODORIC: state-of-the-art database of prokaryotic gene regulation. Nucleic Acids Res 2021; 50:D295-D302. [PMID: 34850133 PMCID: PMC8728284 DOI: 10.1093/nar/gkab1110] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/12/2021] [Accepted: 11/01/2021] [Indexed: 11/14/2022] Open
Abstract
PRODORIC is worldwide one of the largest collections of prokaryotic transcription factor binding sites from multiple bacterial sources with corresponding interpretation and visualization tools. With the introduction of PRODORIC2 in 2017, the transition to a modern web interface and maintainable backend was started. With this latest PRODORIC release the database backend is now fully API-based and provides programmatical access to the complete PRODORIC data. The visualization tools Genome Browser and ProdoNet from the original PRODORIC have been reintroduced and were integrated into the PRODORIC website. Missing input and output options from the original Virtual Footprint were added again for position weight matrix pattern-based searches. The whole PRODORIC dataset was reannotated. Every transcription factor binding site was re-evaluated to increase the overall database quality. During this process, additional parameters, like bound effectors, regulation type and different types of experimental evidence have been added for every transcription factor. Additionally, 109 new transcription factors and 6 new organisms have been added. PRODORIC is publicly available at https://www.prodoric.de.
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Affiliation(s)
- Christian-Alexander Dudek
- Institute of Microbiology and Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Rebenring 56, Braunschweig D-38106, Germany
| | - Dieter Jahn
- Institute of Microbiology and Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Rebenring 56, Braunschweig D-38106, Germany
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10
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Jiang H, Wu F, Wang Y, Feng L, Zhou H, Li Y. Characteristics of in-situ hydrogen biomethanation at mesophilic and thermophilic temperatures. BIORESOURCE TECHNOLOGY 2021; 337:125455. [PMID: 34320739 DOI: 10.1016/j.biortech.2021.125455] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 06/16/2021] [Accepted: 06/20/2021] [Indexed: 06/13/2023]
Abstract
In-situ hydrogen biomethanation is a promising technology to upgrade biogas. The efficiency of biomethanation relies on various parameters, e.g. gas supplement, temperature and hydrogenotrophic methanogens. Therefore, it is important to investigate the characteristics of in-situ hydrogen biomethanation under different conditions. In this study, two experiments (lasted for 91 days and 105 days) were carried out to investigate the impacts of feeding gas and operating conditions on performances of reactors and microorganisms. During the whole experiment, no obvious fluctuation of pH and limitation of gas-liquid mass transfer were found. Results showed that the hydrogenotrophic methanogenesis performed better at thermophilic condition, while the dominant archaea genera at mesophilic and thermophilic temperature was determined to be Methanobacterium and Methanothermobacter, respectively. The highest CH4 content (greater than 90%) was obtained when H2 and CO2 was feeding at ratio of 4:1 and Methanothermobacter was dominant. These findings can provide useful information for promoting hydrogen biomethanation.
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Affiliation(s)
- Hao Jiang
- School of Materials Science&Engineering, Beijing Institute of Technology, Beijing 100081, PR China
| | - Fan Wu
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Biogas Upgrading Utilization, College of New Energy and Materials, China University of Petroleum Beijing (CUPB), Beijing 102249, PR China
| | - Yuchang Wang
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Biogas Upgrading Utilization, College of New Energy and Materials, China University of Petroleum Beijing (CUPB), Beijing 102249, PR China
| | - Lu Feng
- Department of Biological and Chemical Engineering, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark
| | - Hongjun Zhou
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Biogas Upgrading Utilization, College of New Energy and Materials, China University of Petroleum Beijing (CUPB), Beijing 102249, PR China
| | - Yeqing Li
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Biogas Upgrading Utilization, College of New Energy and Materials, China University of Petroleum Beijing (CUPB), Beijing 102249, PR China.
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11
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Lanzilli M, Esercizio N, Vastano M, Xu Z, Nuzzo G, Gallo C, Manzo E, Fontana A, d’Ippolito G. Effect of Cultivation Parameters on Fermentation and Hydrogen Production in the Phylum Thermotogae. Int J Mol Sci 2020; 22:ijms22010341. [PMID: 33396970 PMCID: PMC7795431 DOI: 10.3390/ijms22010341] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 01/19/2023] Open
Abstract
The phylum Thermotogae is composed of a single class (Thermotogae), 4 orders (Thermotogales, Kosmotogales, Petrotogales, Mesoaciditogales), 5 families (Thermatogaceae, Fervidobacteriaceae, Kosmotogaceae, Petrotogaceae, Mesoaciditogaceae), and 13 genera. They have been isolated from extremely hot environments whose characteristics are reflected in the metabolic and phenotypic properties of the Thermotogae species. The metabolic versatility of Thermotogae members leads to a pool of high value-added products with application potentials in many industry fields. The low risk of contamination associated with their extreme culture conditions has made most species of the phylum attractive candidates in biotechnological processes. Almost all members of the phylum, especially those in the order Thermotogales, can produce bio-hydrogen from a variety of simple and complex sugars with yields close to the theoretical Thauer limit of 4 mol H2/mol consumed glucose. Acetate, lactate, and L-alanine are the major organic end products. Thermotagae fermentation processes are influenced by various factors, such as hydrogen partial pressure, agitation, gas sparging, culture/headspace ratio, inoculum, pH, temperature, nitrogen sources, sulfur sources, inorganic compounds, metal ions, etc. Optimization of these parameters will help to fully unleash the biotechnological potentials of Thermotogae and promote their applications in industry. This article gives an overview of how these operational parameters could impact Thermotogae fermentation in terms of sugar consumption, hydrogen yields, and organic acids production.
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Affiliation(s)
- Mariamichela Lanzilli
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
| | - Nunzia Esercizio
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
| | - Marco Vastano
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
| | - Zhaohui Xu
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH 43403, USA;
| | - Genoveffa Nuzzo
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
| | - Carmela Gallo
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
| | - Emiliano Manzo
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
| | - Angelo Fontana
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
| | - Giuliana d’Ippolito
- Istituto di Chimica Biomolecolare (ICB), CNR, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; (M.L.); (N.E.); (M.V.); (G.N.); (C.G.); (E.M.); (A.F.)
- Correspondence: ; Tel.: +39-081-8675096
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12
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Anaerobic digestion performance and microbial community structures in biogas production from whiskey distillers organic by-products. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.biteb.2020.100565] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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13
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Liang YF, Yan LT, Yue Q, Zhao JK, Luo CY, Gao F, Li H, Gao WY. Preparation of a whole cell catalyst overexpressing acetohydroxyacid synthase of Thermotoga maritima and its application in the syntheses of α-hydroxyketones. Sci Rep 2020; 10:15404. [PMID: 32958806 PMCID: PMC7505981 DOI: 10.1038/s41598-020-72416-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 08/31/2020] [Indexed: 11/30/2022] Open
Abstract
The large catalytic subunit of acetohydroxyacid synthase (AHAS, EC 2.2.1.6) of Thermotoga maritima (TmcAHAS) was prepared in this study. It possesses high specific activity and excellent stability. The protein and a whole cell catalyst overexpressing the protein were applied to the preparation of α-hydroxyketones including acetoin (AC), 3-hydroxy-2-pentanone (HP), and (R)-phenylacetylcarbinol (R-PAC). The results show that AC and HP could be produced in high yields (84% and 62%, respectively), while R-PAC could be synthesized in a high yield (about 78%) with an R/S ratio of 9:1. Therefore, TmcAHAS and the whole cell catalyst overexpressing the protein could be practically useful bio-catalysts in the preparation of α-hydroxyketones including AC, HP, and R-PAC. To the best of our knowledge, this is the first time that bacterial AHAS was used as a catalyst to prepare HP with a good yield, and also the first time that TmcAHAS was employed to synthesize AC and R-PAC.
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Affiliation(s)
- Yan-Fei Liang
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China
| | - Le-Tian Yan
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China
| | - Qiao Yue
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China
| | - Ji-Kui Zhao
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China
| | - Cai-Yun Luo
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China
| | - Feng Gao
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China
| | - Heng Li
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China.
| | - Wen-Yun Gao
- College of Life Sciences, Northwest University, 229 North Taibai Road, Xi'an, 710069, Shaanxi, People's Republic of China.
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14
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Mattossovich R, Merlo R, Miggiano R, Valenti A, Perugino G. O6-alkylguanine-DNA Alkyltransferases in Microbes Living on the Edge: From Stability to Applicability. Int J Mol Sci 2020; 21:E2878. [PMID: 32326075 PMCID: PMC7216122 DOI: 10.3390/ijms21082878] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/09/2020] [Accepted: 04/16/2020] [Indexed: 02/06/2023] Open
Abstract
The genome of living cells is continuously exposed to endogenous and exogenous attacks, and this is particularly amplified at high temperatures. Alkylating agents cause DNA damage, leading to mutations and cell death; for this reason, they also play a central role in chemotherapy treatments. A class of enzymes known as AGTs (alkylguanine-DNA-alkyltransferases) protects the DNA from mutations caused by alkylating agents, in particular in the recognition and repair of alkylated guanines in O6-position. The peculiar irreversible self-alkylation reaction of these enzymes triggered numerous studies, especially on the human homologue, in order to identify effective inhibitors in the fight against cancer. In modern biotechnology, engineered variants of AGTs are developed to be used as protein tags for the attachment of chemical ligands. In the last decade, research on AGTs from (hyper)thermophilic sources proved useful as a model system to clarify numerous phenomena, also common for mesophilic enzymes. This review traces recent progress in this class of thermozymes, emphasizing their usefulness in basic research and their consequent advantages for in vivo and in vitro biotechnological applications.
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Affiliation(s)
- Rosanna Mattossovich
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
| | - Rosa Merlo
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
| | - Riccardo Miggiano
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy;
| | - Anna Valenti
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
| | - Giuseppe Perugino
- Institute of Bioscience and BioResources, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy; (R.M.); (R.M.)
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15
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d'Ippolito G, Landi S, Esercizio N, Lanzilli M, Vastano M, Dipasquale L, Pradhan N, Fontana A. CO 2-Induced Transcriptional Reorganization: Molecular Basis of Capnophillic Lactic Fermentation in Thermotoga neapolitana. Front Microbiol 2020; 11:171. [PMID: 32132982 PMCID: PMC7039931 DOI: 10.3389/fmicb.2020.00171] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 01/24/2020] [Indexed: 11/25/2022] Open
Abstract
Capnophilic lactic fermentation (CLF) is a novel anaplerotic pathway able to convert sugars to lactic acid (LA) and hydrogen using CO2 as carbon enhancer in the hyperthermophilic bacterium Thermotoga neapolitana. In order to give further insights into CLF metabolic networks, we investigated the transcriptional modification induced by CO2 using a RNA-seq approach. Transcriptomic analysis revealed 1601 differentially expressed genes (DEGs) in an enriched CO2 atmosphere over a total of 1938 genes of the T. neapolitana genome. Transcription of PFOR and LDH genes belonging to the CLF pathway was up-regulated by CO2 together with 6-phosphogluconolactonase (6PGL) and 6-phosphogluconate dehydratase (EDD) of the Entner–Doudoroff (ED) pathway. The transcriptomic study also revealed up-regulation of genes coding for the flavin-based enzymes NADH-dependent reduced ferredoxin:NADP oxidoreductase (NFN) and NAD-ferredoxin oxidoreductase (RNF) that control supply of reduced ferredoxin and NADH and allow energy conservation-based sodium translocation through the cell membrane. These results support the hypothesis that CO2 induces rearrangement of the central carbon metabolism together with activation of mechanisms that increase availability of the reducing equivalents that are necessary to sustain CLF. In this view, this study reports a first rationale of the molecular basis of CLF in T. neapolitana and provides a list of target genes for the biotechnological implementation of this process.
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Affiliation(s)
- Giuliana d'Ippolito
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
| | - Simone Landi
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
| | - Nunzia Esercizio
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
| | - Mariamichella Lanzilli
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
| | - Marco Vastano
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
| | - Laura Dipasquale
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
| | - Nirakar Pradhan
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
| | - Angelo Fontana
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry, Italian National Research Council (CNR), Pozzuoli, Italy
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16
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Mattossovich R, Merlo R, Fontana A, d'Ippolito G, Terns MP, Watts EA, Valenti A, Perugino G. A journey down to hell: new thermostable protein-tags for biotechnology at high temperatures. Extremophiles 2019; 24:81-91. [PMID: 31555904 DOI: 10.1007/s00792-019-01134-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 09/13/2019] [Indexed: 12/14/2022]
Abstract
The specific labelling of proteins in recent years has made use of self-labelling proteins, such as the SNAP-tag® and the Halotag®. These enzymes, by their nature or suitably engineered, have the ability to specifically react with their respective substrates, but covalently retaining a part of them in the catalytic site upon reaction. This led to the synthesis of substrates conjugated with, e.g., fluorophores (proposing them as alternatives to fluorescent proteins), but also with others chemical groups, for numerous biotechnological applications. Recently, a mutant of the OGT from Saccharolobus solfataricus (H5) very stable to high temperatures and in the presence of physical and chemical denaturing agents has been proposed as a thermostable SNAP-tag® for in vivo and in vitro harsh reaction conditions. Here, we show two new thermostable OGTs from Thermotoga neapolitana and Pyrococcus furiosus, which, respectively, display a higher catalytic activity and thermostability respect to H5, proposing them as alternatives for in vivo studies in these extreme model organisms.
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Affiliation(s)
- Rosanna Mattossovich
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy
| | - Rosa Merlo
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy
| | - Angelo Fontana
- Institute of Biomolecular Chemistry, National Council of Research of Italy, Via Campi Flegrei, 34, 80078, Pozzuoli, NA, Italy
| | - Giuliana d'Ippolito
- Institute of Biomolecular Chemistry, National Council of Research of Italy, Via Campi Flegrei, 34, 80078, Pozzuoli, NA, Italy
| | - Michael P Terns
- Departments of Biochemistry and Molecular Biology, Genetics, and Microbiology, University of Georgia, Athens, GA, USA
| | - Elizabeth A Watts
- Departments of Biochemistry and Molecular Biology, Genetics, and Microbiology, University of Georgia, Athens, GA, USA
| | - Anna Valenti
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy
| | - Giuseppe Perugino
- Institute of Biosciences and BioResources, National Council of Research of Italy, Via P. Castellino 111, 80131, Naples, Italy.
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17
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Huang L, Zhang H, Wu P, Entwistle S, Li X, Yohe T, Yi H, Yang Z, Yin Y. dbCAN-seq: a database of carbohydrate-active enzyme (CAZyme) sequence and annotation. Nucleic Acids Res 2019; 46:D516-D521. [PMID: 30053267 PMCID: PMC5753378 DOI: 10.1093/nar/gkx894] [Citation(s) in RCA: 175] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 09/22/2017] [Indexed: 01/08/2023] Open
Abstract
Carbohydrate-active enzyme (CAZymes) are not only the most important enzymes for bioenergy and agricultural industries, but also very important for human health, in that human gut microbiota encode hundreds of CAZyme genes in their genomes for degrading various dietary and host carbohydrates. We have built an online database dbCAN-seq (http://cys.bios.niu.edu/dbCAN_seq) to provide pre-computed CAZyme sequence and annotation data for 5,349 bacterial genomes. Compared to the other CAZyme resources, dbCAN-seq has the following new features: (i) a convenient download page to allow batch download of all the sequence and annotation data; (ii) an annotation page for every CAZyme to provide the most comprehensive annotation data; (iii) a metadata page to organize the bacterial genomes according to species metadata such as disease, habitat, oxygen requirement, temperature, metabolism; (iv) a very fast tool to identify physically linked CAZyme gene clusters (CGCs) and (v) a powerful search function to allow fast and efficient data query. With these unique utilities, dbCAN-seq will become a valuable web resource for CAZyme research, with a focus complementary to dbCAN (automated CAZyme annotation server) and CAZy (CAZyme family classification and reference database).
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Affiliation(s)
- Le Huang
- College of Computer and Control Engineering, Nankai University, Tianjin, China
| | - Han Zhang
- College of Computer and Control Engineering, Nankai University, Tianjin, China
| | - Peizhi Wu
- College of Computer and Control Engineering, Nankai University, Tianjin, China
| | - Sarah Entwistle
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL, USA
| | - Xueqiong Li
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL, USA
| | - Tanner Yohe
- Department of Computer Science, Northern Illinois University, DeKalb, IL, USA
| | - Haidong Yi
- College of Computer and Control Engineering, Nankai University, Tianjin, China
| | - Zhenglu Yang
- College of Computer and Control Engineering, Nankai University, Tianjin, China
| | - Yanbin Yin
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL, USA
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18
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Xu S, Zhang Y, Luo L, Liu H. Startup performance of microbial electrolysis cell assisted anaerobic digester (MEC-AD) with pre-acclimated activated carbon. ACTA ACUST UNITED AC 2019; 5:91-98. [PMID: 31193294 PMCID: PMC6524652 DOI: 10.1016/j.biteb.2018.12.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/11/2018] [Accepted: 12/12/2018] [Indexed: 12/02/2022]
Abstract
The feasibility of using pre-acclimated activated carbon to start up microbial electrolysis cell assisted anaerobic digester (MEC-AD) has been testified in this study. Two identical lab-scale digesters were separately packed with granular activated carbon (GAC) and powered activated carbon (PAC), which were initially acclimated as anaerobic digester and then transferred to MEC-AD. When a voltage of 0.5 V was applied, increased methane generation and substrate removal rates were observed. Hydrogenotrophic methanogens predominated in both digesters before and after transition, indicating that the pre-cultured microbial community on carbon materials could provide necessary microbiome favorable for starting up MECs. Although a low abundance of Geobacter was detected in inoculum, a rapid propagation could be realized when reactors were subjected to the electro-stimulation. The abundance of Methanosarcina closely attached to PAC was four times than that of GAC, which might be partially contributed to the improved resilience of anaerobic digester subjected to electro-stimulation. Pre-acclimated PAC/GAC are favorable for starting up MEC-AD. Methane yield was increased by ~30% when transferring AD to MEC-AD. Abundance of electroactive bacteria on pre-enriched PAC was higher than GAC. The rapid propagation of Geobacter was found in MEC-AD.
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Affiliation(s)
- Suyun Xu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Yuchen Zhang
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Liwen Luo
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Hongbo Liu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China
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19
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Qin X, Ji M, Wu X, Li C, Gao Y, Li J, Wu Q, Zhang X, Zhang Z. Response of treatment performance and microbial community structure to the temporary suspension of an industrial anaerobic bioreactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 646:229-237. [PMID: 30053667 DOI: 10.1016/j.scitotenv.2018.07.309] [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: 05/21/2018] [Revised: 07/21/2018] [Accepted: 07/22/2018] [Indexed: 06/08/2023]
Abstract
In this study, a novel type of mesophilic anaerobic bioreactor-an expanded granular sludge bed (EGSB)-was utilized to explore the effect of suspending reactor operation on the treatment performance and the microbial community structure. The parameters of performance and bacterial community before and after a four-week suspension were compared for the starch processing wastewater treatment bioreactor. The results indicate that the removal rate of the organic matter remained higher than 90%, although the biomass significantly decreased after restarting the reactor. However, the relatively stable microbial community structure before the suspension was altered significantly during the restart and post-running stages. This change was primarily due to variability in satellite species and the substitution effect of different dominant bacteria. For example, some non-major carbohydrate-degrading bacteria that were sensitive to nutrition deficiency, such as Desulfovibrio and Geobacter, were dramatically reduced after the suspension. In contrast, the stress of starvation stimulated the reproduction of hydrolytic bacteria, such as Macellibacteroides. However, the high bacterial diversity index (6.12-6.65) and the longstanding core species, including Chloroflexi, Cloacimonetes, Ignavibacteriae, Thermotogae and Euryarchaeota, maintained the functional stability of the reactor. Consequently, although the total bacteria decreased significantly after reactor operation was suspended, sufficient functional bacteria supported by the high diversity, as well as the longstanding core species, guaranteed the effective degradation after suspension.
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Affiliation(s)
- Xianchao Qin
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Mengmeng Ji
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaogang Wu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Chunjie Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Yueshu Gao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Ji Li
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Qiaoyu Wu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaojun Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
| | - Zhenjia Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China.
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20
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Grimaud F, Pizzut-Serin S, Tarquis L, Ladevèze S, Morel S, Putaux JL, Potocki-Veronese G. In Vitro Synthesis and Crystallization of β-1,4-Mannan. Biomacromolecules 2018; 20:846-853. [DOI: 10.1021/acs.biomac.8b01457] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Florent Grimaud
- LISBP, CNRS, INRA, INSAT, Université de Toulouse, F-31400 Toulouse, France
| | | | - Laurence Tarquis
- LISBP, CNRS, INRA, INSAT, Université de Toulouse, F-31400 Toulouse, France
| | - Simon Ladevèze
- LISBP, CNRS, INRA, INSAT, Université de Toulouse, F-31400 Toulouse, France
| | - Sandrine Morel
- LISBP, CNRS, INRA, INSAT, Université de Toulouse, F-31400 Toulouse, France
| | - Jean-Luc Putaux
- Univ. Grenoble Alpes, CNRS, CERMAV, F-38000 Grenoble, France
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21
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Lee LL, Blumer-Schuette SE, Izquierdo JA, Zurawski JV, Loder AJ, Conway JM, Elkins JG, Podar M, Clum A, Jones PC, Piatek MJ, Weighill DA, Jacobson DA, Adams MWW, Kelly RM. Genus-Wide Assessment of Lignocellulose Utilization in the Extremely Thermophilic Genus Caldicellulosiruptor by Genomic, Pangenomic, and Metagenomic Analyses. Appl Environ Microbiol 2018; 84:e02694-17. [PMID: 29475869 PMCID: PMC5930323 DOI: 10.1128/aem.02694-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 02/16/2018] [Indexed: 11/20/2022] Open
Abstract
Metagenomic data from Obsidian Pool (Yellowstone National Park, USA) and 13 genome sequences were used to reassess genus-wide biodiversity for the extremely thermophilic Caldicellulosiruptor The updated core genome contains 1,401 ortholog groups (average genome size for 13 species = 2,516 genes). The pangenome, which remains open with a revised total of 3,493 ortholog groups, encodes a variety of multidomain glycoside hydrolases (GHs). These include three cellulases with GH48 domains that are colocated in the glucan degradation locus (GDL) and are specific determinants for microcrystalline cellulose utilization. Three recently sequenced species, Caldicellulosiruptor sp. strain Rt8.B8 (renamed here Caldicellulosiruptor morganii), Thermoanaerobacter cellulolyticus strain NA10 (renamed here Caldicellulosiruptor naganoensis), and Caldicellulosiruptor sp. strain Wai35.B1 (renamed here Caldicellulosiruptor danielii), degraded Avicel and lignocellulose (switchgrass). C. morganii was more efficient than Caldicellulosiruptor bescii in this regard and differed from the other 12 species examined, both based on genome content and organization and in the specific domain features of conserved GHs. Metagenomic analysis of lignocellulose-enriched samples from Obsidian Pool revealed limited new information on genus biodiversity. Enrichments yielded genomic signatures closely related to that of Caldicellulosiruptor obsidiansis, but there was also evidence for other thermophilic fermentative anaerobes (Caldanaerobacter, Fervidobacterium, Caloramator, and Clostridium). One enrichment, containing 89.8% Caldicellulosiruptor and 9.7% Caloramator, had a capacity for switchgrass solubilization comparable to that of C. bescii These results refine the known biodiversity of Caldicellulosiruptor and indicate that microcrystalline cellulose degradation at temperatures above 70°C, based on current information, is limited to certain members of this genus that produce GH48 domain-containing enzymes.IMPORTANCE The genus Caldicellulosiruptor contains the most thermophilic bacteria capable of lignocellulose deconstruction, which are promising candidates for consolidated bioprocessing for the production of biofuels and bio-based chemicals. The focus here is on the extant capability of this genus for plant biomass degradation and the extent to which this can be inferred from the core and pangenomes, based on analysis of 13 species and metagenomic sequence information from environmental samples. Key to microcrystalline hydrolysis is the content of the glucan degradation locus (GDL), a set of genes encoding glycoside hydrolases (GHs), several of which have GH48 and family 3 carbohydrate binding module domains, that function as primary cellulases. Resolving the relationship between the GDL and lignocellulose degradation will inform efforts to identify more prolific members of the genus and to develop metabolic engineering strategies to improve this characteristic.
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Affiliation(s)
- Laura L Lee
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Sara E Blumer-Schuette
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Javier A Izquierdo
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Jeffrey V Zurawski
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Andrew J Loder
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Jonathan M Conway
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - James G Elkins
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Mircea Podar
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Alicia Clum
- DOE Joint Genome Institute, Walnut Creek, California, USA
| | - Piet C Jones
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Marek J Piatek
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | | | - Daniel A Jacobson
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
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22
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Zamanzadeh M, Hagen LH, Svensson K, Linjordet R, Horn SJ. Biogas production from food waste via co-digestion and digestion- effects on performance and microbial ecology. Sci Rep 2017; 7:17664. [PMID: 29247239 PMCID: PMC5732306 DOI: 10.1038/s41598-017-15784-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/02/2017] [Indexed: 12/13/2022] Open
Abstract
In this work, performance and microbial structure of a digestion (food waste-only) and a co-digestion process (mixture of cow manure and food waste) were studied at mesophilic (37 °C) and thermophilic (55 °C) temperatures. The highest methane yield (480 mL/g VS) was observed in the mesophilic digester (MDi) fed with food waste alone. The mesophilic co-digestion of food waste and manure (McoDi) yielded 26% more methane than the sum of individual digestions of manure and food waste. The main volatile fatty acid (VFA) in the mesophilic systems was acetate, averaging 93 and 172 mg/L for McoDi and MDi, respectively. Acetate (2150 mg/L) and propionate (833 mg/L) were the main VFAs in the thermophilic digester (TDi), while propionate (163 mg/L) was the major VFA in the thermophilic co-digester (TcoDi). The dominant bacteria in MDi was Chloroflexi (54%), while Firmicutes was dominant in McoDi (60%). For the mesophilic reactors, the dominant archaea was Methanosaeta in MDi, while Methanobacterium and Methanosaeta had similar abundance in McoDi. In the thermophilic systems, the dominant bacteria were Thermotogae, Firmicutes and Synergistetes in both digesters, however, the relative abundance of these phyla were different. For archaea, the genus Methanothermobacter were entirely dominant in both TDi and TcoDi.
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Affiliation(s)
- Mirzaman Zamanzadeh
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P. O. Box 5003, N-1432, Ås, Norway
- Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, P.O. Box 14155-6446, Tehran, Iran
- Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada
| | - Live Heldal Hagen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P. O. Box 5003, N-1432, Ås, Norway
| | - Kine Svensson
- Nibio, Norwegian Institute of Bioeconomy Research, Ås, Norway
| | - Roar Linjordet
- Nibio, Norwegian Institute of Bioeconomy Research, Ås, Norway
| | - Svein Jarle Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P. O. Box 5003, N-1432, Ås, Norway.
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Functional characterization and crystal structure of thermostable amylase from Thermotoga petrophila , reveals high thermostability and an unusual form of dimerization. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017. [DOI: 10.1016/j.bbapap.2017.06.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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24
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Arab G, Razaviarani V, Sheng Z, Liu Y, McCartney D. Benefits to decomposition rates when using digestate as compost co-feedstock: Part II - Focus on microbial community dynamics. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 68:85-95. [PMID: 28757223 DOI: 10.1016/j.wasman.2017.07.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/29/2017] [Accepted: 07/12/2017] [Indexed: 06/07/2023]
Abstract
Linkage between composting reactor performance and microbial community dynamics was investigated during co-composting of digestate and fresh feedstock (organic fraction of municipal solid waste) using 25L reactors. Previously, the relationship between composting performance and various physicochemical parameters were reported in Part I of the study (Arab and McCartney, 2017). Three digestate to fresh feedstock ratios (0, 40, and 100%; wet weight basis) were selected for analysis of microbial community dynamics. The 40% ratio was selected because it was found to perform the best (Arab and McCartney, 2017). Illumina sequencing results revealed that the reactor with a greater composting performance (higher organic matter degradation and higher heat generation; 40% ratio) was associated with higher microbial diversity. Two specific bacterial orders that might result in higher performance were Thermoactinomycetaceae and Actinomycetales with a higher sequence abundance during thermophilic composting phase and during the maturing composting phase, respectively. Galactomyces, Pichia, Chaetomium, and Acremonium were the four fungal genera that are probably also involved in higher organic matter degradation in the reactor with better performance. The redundancy analysis (RDA) biplot indicated that among the studied environmental variables, temperature, total ammonia nitrogen and nitrate concentration accounted for much of the major shifts in microbial sequence abundance during the co-composting process.
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Affiliation(s)
- Golnaz Arab
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton T6G 1H9, Canada.
| | - Vahid Razaviarani
- Department of Chemical Engineering, American University of Middle East, 250 St, Eqaila, Kuwait.
| | - Zhiya Sheng
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton T6G 1H9, Canada.
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton T6G 1H9, Canada.
| | - Daryl McCartney
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton T6G 1H9, Canada; Edmonton Waste Management Centre of Excellence, Site 310, 250 Aurum Road NE, Edmonton T6S 1G9, Canada.
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25
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Hirano SI, Matsumoto N. Electrochemically applied potentials induce growth and metabolic shift changes in the hyperthermophilic bacterium Thermotoga maritima MSB8. Biosci Biotechnol Biochem 2017; 81:1619-1626. [DOI: 10.1080/09168451.2017.1329618] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Bioelectrochemical systems are an attractive technology for regulating microbial activity. The effect of an applied potential on hydrolysis of starch in Thermotoga maritima as a model bacterium was investigated in this study. A cathodic potential (−0.6 and −0.8 V) induced 5-h earlier growth initiation of T. maritima with starch as the polymeric substrate than that without electrochemical regulation. Moreover, metabolic patterns of starch consumption were altered by the cathodic potential. While acetate, H2, and CO2 were the major products of starch consumption in the control experiment without electrolysis, lactate accumulation was detected rather than decreased acetate and H2 levels in the bioelectrochemical system experiments with the cathodic potential. These results indicate that the applied potential could control microbial activities related to the hydrolysis of polymeric organic substances and shift carbon and electron flux to a lactate-producing reaction in T. maritima.
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Affiliation(s)
- Shin-ichi Hirano
- Biotechnology Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Abiko-shi, Japan
| | - Norio Matsumoto
- Biotechnology Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Abiko-shi, Japan
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26
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Counts JA, Zeldes BM, Lee LL, Straub CT, Adams MWW, Kelly RM. Physiological, metabolic and biotechnological features of extremely thermophilic microorganisms. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2017; 9. [PMID: 28206708 DOI: 10.1002/wsbm.1377] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Revised: 11/23/2016] [Accepted: 11/30/2016] [Indexed: 12/12/2022]
Abstract
The current upper thermal limit for life as we know it is approximately 120°C. Microorganisms that grow optimally at temperatures of 75°C and above are usually referred to as 'extreme thermophiles' and include both bacteria and archaea. For over a century, there has been great scientific curiosity in the basic tenets that support life in thermal biotopes on earth and potentially on other solar bodies. Extreme thermophiles can be aerobes, anaerobes, autotrophs, heterotrophs, or chemolithotrophs, and are found in diverse environments including shallow marine fissures, deep sea hydrothermal vents, terrestrial hot springs-basically, anywhere there is hot water. Initial efforts to study extreme thermophiles faced challenges with their isolation from difficult to access locales, problems with their cultivation in laboratories, and lack of molecular tools. Fortunately, because of their relatively small genomes, many extreme thermophiles were among the first organisms to be sequenced, thereby opening up the application of systems biology-based methods to probe their unique physiological, metabolic and biotechnological features. The bacterial genera Caldicellulosiruptor, Thermotoga and Thermus, and the archaea belonging to the orders Thermococcales and Sulfolobales, are among the most studied extreme thermophiles to date. The recent emergence of genetic tools for many of these organisms provides the opportunity to move beyond basic discovery and manipulation to biotechnologically relevant applications of metabolic engineering. WIREs Syst Biol Med 2017, 9:e1377. doi: 10.1002/wsbm.1377 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- James A Counts
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Benjamin M Zeldes
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Laura L Lee
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Christopher T Straub
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
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Thomas L, Ram H, Singh VP. Evolutionary Relationships and Taxa-Specific Conserved Signature Indels Among Cellulases of Archaea, Bacteria, and Eukarya. J Comput Biol 2017; 24:1029-1042. [PMID: 28177649 DOI: 10.1089/cmb.2016.0161] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The cellulases from different cellulolytic organisms have evolutionary relationships, which range from single-celled prokaryotes to the complex eukaryotes of the living world. This in silico analysis revealed the presence of a conserved cellulase domain along with evolutionary relationships among cellulases from several species of Archaea, Bacteria, and Eukarya. The amino acid sequences of cellulases from Archaea and Bacteria showed closer identity with their domain or phylum members that provided insights into convergent and divergent evolution of cellulases from other enzymes with different substrate specificities. Evolutionary relatedness was also observed in phylogenetic trees among a number of cellulase sequences of diverse taxa. In cellulases, propensity for alanine, glycine, leucine, serine, and threonine was high, but low for cysteine, histidine, and methionine. Catalytic aspartic acid had a higher propensity than glutamic acid, and both were involved in regular expression patterns. Characteristic group and multigroup-specific conserved signature indels located in the catalytic domains of cellulases were observed that further clarified evolutionary relationships. These indels can be distinctive molecular tools for understanding phylogeny and identification of unknown cellulolytic species of common evolutionary descent in different environments.
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Affiliation(s)
- Lebin Thomas
- Applied Microbiology and Biotechnology Laboratory, Department of Botany, University of Delhi , Delhi, India
| | - Hari Ram
- Applied Microbiology and Biotechnology Laboratory, Department of Botany, University of Delhi , Delhi, India
| | - Ved Pal Singh
- Applied Microbiology and Biotechnology Laboratory, Department of Botany, University of Delhi , Delhi, India
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28
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Contribution of Pentose Catabolism to Molecular Hydrogen Formation by Targeted Disruption of Arabinose Isomerase (araA) in the Hyperthermophilic Bacterium Thermotoga maritima. Appl Environ Microbiol 2017; 83:AEM.02631-16. [PMID: 27940539 DOI: 10.1128/aem.02631-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 11/21/2016] [Indexed: 12/15/2022] Open
Abstract
Thermotoga maritima ferments a broad range of sugars to form acetate, carbon dioxide, traces of lactate, and near theoretic yields of molecular hydrogen (H2). In this organism, the catabolism of pentose sugars such as arabinose depends on the interaction of the pentose phosphate pathway with the Embden-Myerhoff and Entner-Doudoroff pathways. Although the values for H2 yield have been determined using pentose-supplemented complex medium and predicted by metabolic pathway reconstruction, the actual effect of pathway elimination on hydrogen production has not been reported due to the lack of a genetic method for the creation of targeted mutations. Here, a spontaneous and genetically stable pyrE deletion mutant was isolated and used as a recipient to refine transformation methods for its repair by homologous recombination. To verify the occurrence of recombination and to assess the frequency of crossover events flanking the deleted region, a synthetic pyrE allele, encoding synonymous nucleotide substitutions, was used. Targeted inactivation of araA (encoding arabinose isomerase) in the pyrE mutant was accomplished using a divergent, codon-optimized Thermosipho africanus pyrE allele fused to the T. maritima groES promoter as a genetic marker. Mutants lacking araA were unable to catabolize arabinose in a defined medium. The araA mutation was then repaired using targeted recombination. Levels of synthesis of H2 using arabinose-supplemented complex medium by wild-type and araA mutant cell lines were compared. The difference between strains provided a direct measurement of H2 production that was dependent on arabinose consumption. Development of a targeted recombination system for genetic manipulation of T. maritima provides a new strategy to explore H2 formation and life at an extremely high temperature in the bacterial domain. IMPORTANCE We describe here the development of a genetic system for manipulation of Thermotoga maritima T. maritima is a hyperthermophilic anaerobic bacterium that is well known for its efficient synthesis of molecular hydrogen (H2) from the fermentation of sugars. Despite considerable efforts to advance compatible genetic methods, chromosome manipulation has remained elusive and hindered use of T. maritima or its close relatives as model hyperthermophiles. Lack of a genetic method also prevented efforts to manipulate specific metabolic pathways to measure their contributions to H2 yield. To overcome this barrier, a homologous chromosomal recombination method was developed and used to characterize the contribution of arabinose catabolism to H2 formation. We report here a stable genetic method for a hyperthermophilic bacterium that will advance studies on the basic and synthetic biology of Thermotogales.
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Klassen V, Blifernez-Klassen O, Wibberg D, Winkler A, Kalinowski J, Posten C, Kruse O. Highly efficient methane generation from untreated microalgae biomass. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:186. [PMID: 28725266 PMCID: PMC5513056 DOI: 10.1186/s13068-017-0871-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 07/10/2017] [Indexed: 05/16/2023]
Abstract
BACKGROUND The fact that microalgae perform very efficiently photosynthetic conversion of sunlight into chemical energy has moved them into the focus of regenerative fuel research. Especially, biogas generation via anaerobic digestion is economically attractive due to the comparably simple apparative process technology and the theoretical possibility of converting the entire algal biomass to biogas/methane. In the last 60 years, intensive research on biogas production from microalgae biomass has revealed the microalgae as a rather challenging substrate for anaerobic digestion due to its high cell wall recalcitrance and unfavorable protein content, which requires additional pretreatment and co-fermentation strategies for sufficient fermentation. However, sustainable fuel generation requires the avoidance of cost/energy intensive biomass pretreatments to achieve positive net-energy process balance. RESULTS Cultivation of microalgae in replete and limited nitrogen culture media conditions has led to the formation of protein-rich and low protein biomass, respectively, with the last being especially optimal for continuous fermentation. Anaerobic digestion of nitrogen limited biomass (low-N BM) was characterized by a stable process with low levels of inhibitory substances and resulted in extraordinary high biogas, and subsequently methane productivity [750 ± 15 and 462 ± 9 mLN g-1 volatile solids (VS) day-1, respectively], thus corresponding to biomass-to-methane energy conversion efficiency of up to 84%. The microbial community structure within this highly efficient digester revealed a clear predominance of the phyla Bacteroidetes and the family Methanosaetaceae among the Bacteria and Archaea, respectively. The fermentation of replete nitrogen biomass (replete-N BM), on the contrary, was demonstrated to be less productive (131 ± 33 mLN CH4 g-1VS day-1) and failed completely due to acidosis, caused through high ammonia/ammonium concentrations. The organization of the microbial community of the failed (replete-N) digester differed greatly compared to the stable low-N digester, presenting a clear shift to the phyla Firmicutes and Thermotogae, and the archaeal population shifted from acetoclastic to hydrogenotrophic methanogenesis. CONCLUSIONS The present study underlines the importance of cultivation conditions and shows the practicability of microalgae biomass usage as mono-substrate for highly efficient continuous fermentation to methane without any pretreatment with almost maximum practically achievable energy conversion efficiency (biomass to methane).Graphical abstractGrowth condition dependence of anaerobic conversion efficiency of microalgae biomass to methane.
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Affiliation(s)
- Viktor Klassen
- Department of Biology/Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Olga Blifernez-Klassen
- Department of Biology/Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Daniel Wibberg
- Department of Biology/Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Anika Winkler
- Department of Biology/Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Jörn Kalinowski
- Department of Biology/Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Clemens Posten
- Institute of Life Science Engineering (KIT), Bioprocess Engineering, University of Karlsruhe, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Olaf Kruse
- Department of Biology/Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany
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Loder AJ, Zeldes BM, Conway JM, Counts JA, Straub CT, Khatibi PA, Lee LL, Vitko NP, Keller MW, Rhaesa AM, Rubinstein GM, Scott IM, Lipscomb GL, Adams MW, Kelly RM. Extreme Thermophiles as Metabolic Engineering Platforms: Strategies and Current Perspective. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1002/9783527807796.ch14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Andrew J. Loder
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Benjamin M. Zeldes
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Jonathan M. Conway
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - James A. Counts
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Christopher T. Straub
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Piyum A. Khatibi
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Laura L. Lee
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Nicholas P. Vitko
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Matthew W. Keller
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Amanda M. Rhaesa
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Gabe M. Rubinstein
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Israel M. Scott
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Gina L. Lipscomb
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Michael W.W. Adams
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Robert M. Kelly
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
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Zamanzadeh M, Hagen LH, Svensson K, Linjordet R, Horn SJ. Anaerobic digestion of food waste - Effect of recirculation and temperature on performance and microbiology. WATER RESEARCH 2016; 96:246-54. [PMID: 27060528 DOI: 10.1016/j.watres.2016.03.058] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 03/16/2016] [Accepted: 03/25/2016] [Indexed: 05/07/2023]
Abstract
Recirculation of digestate was investigated as a strategy to dilute the food waste before feeding to anaerobic digesters, and its effects on microbial community structure and performance were studied. Two anaerobic digesters with digestate recirculation were operated at 37 °C (MD + R) and 55 °C (TD + R) and compared to two additional digesters without digestate recirculation operated at the same temperatures (MD and TD). The MD + R digester demonstrated quite stable and similar performance to the MD digester in terms of the methane yield (around 480 mL CH4 per gVSadded). In both MD and MD + R Methanosaeta was the dominant archaea. However, the bacterial community structure was significantly different in the two digesters. Firmicutes dominated in the MD + R, while Chloroflexi was the dominant phylum in the MD. Regarding the thermophilic digesters, the TD + R showed the lowest methane yield (401 mL CH4 per gVSadded) and accumulation of VFAs. In contrast to the mesophilic digesters, the microbial communities in the thermophilic digesters were rather similar, consisting mainly of the phyla Firmicutes, Thermotoga, Synergistetes and the hydrogenotrophic methanogen Methanothermobacter. The impact of ammonia inhibition was different depending on the digesters configurations and operating temperatures.
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Affiliation(s)
- Mirzaman Zamanzadeh
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P. O. Box 5003, N-1432 Ås, Norway
| | - Live H Hagen
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P. O. Box 5003, N-1432 Ås, Norway
| | - Kine Svensson
- NIBIO, Norwegian Institute of Bioeconomy Research, P.O. Box 115, N-1431 Ås, Norway
| | - Roar Linjordet
- NIBIO, Norwegian Institute of Bioeconomy Research, P.O. Box 115, N-1431 Ås, Norway
| | - Svein J Horn
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P. O. Box 5003, N-1432 Ås, Norway.
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Maus I, Cibis KG, Bremges A, Stolze Y, Wibberg D, Tomazetto G, Blom J, Sczyrba A, König H, Pühler A, Schlüter A. Genomic characterization of Defluviitoga tunisiensis L3, a key hydrolytic bacterium in a thermophilic biogas plant and its abundance as determined by metagenome fragment recruitment. J Biotechnol 2016; 232:50-60. [PMID: 27165504 DOI: 10.1016/j.jbiotec.2016.05.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 05/02/2016] [Accepted: 05/02/2016] [Indexed: 12/17/2022]
Abstract
The genome sequence of Defluviitoga tunisiensis L3 originating from a thermophilic biogas-production plant was established and recently published as Genome Announcement by our group. The circular chromosome of D. tunisiensis L3 has a size of 2,053,097bp and a mean GC content of 31.38%. To analyze the D. tunisiensis L3 genome sequence in more detail, a phylogenetic analysis of completely sequenced Thermotogae strains based on shared core genes was performed. It appeared that Petrotoga mobilis DSM 10674(T), originally isolated from a North Sea oil-production well, is the closest relative of D. tunisiensis L3. Comparative genome analyses of P. mobilis DSM 10674(T) and D. tunisiensis L3 showed moderate similarities regarding occurrence of orthologous genes. Both genomes share a common set of 1351 core genes. Reconstruction of metabolic pathways important for the biogas production process revealed that the D. tunisiensis L3 genome encodes a large set of genes predicted to facilitate utilization of a variety of complex polysaccharides including cellulose, chitin and xylan. Ethanol, acetate, hydrogen (H2) and carbon dioxide (CO2) were found as possible end-products of the fermentation process. The latter three metabolites are considered to represent substrates for methanogenic Archaea, the key organisms in the final step of the anaerobic digestion process. To determine the degree of relatedness between D. tunisiensis L3 and dominant biogas community members within the thermophilic biogas-production plant, metagenome sequences obtained from the corresponding microbial community were mapped onto the L3 genome sequence. This fragment recruitment revealed that the D. tunisiensis L3 genome is almost completely covered with metagenome sequences featuring high matching accuracy. This result indicates that strains highly related or even identical to the reference strain D. tunisiensis L3 play a dominant role within the community of the thermophilic biogas-production plant.
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Affiliation(s)
- Irena Maus
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | - Katharina Gabriela Cibis
- Institute of Microbiology and Wine Research, Johannes Gutenberg University Mainz, 55122 Mainz, Germany
| | - Andreas Bremges
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany; Faculty of Technology, Bielefeld University, 33615 Bielefeld, Germany
| | - Yvonne Stolze
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | - Daniel Wibberg
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | | | - Jochen Blom
- Department of Bioinformatics and Systems Biology, Justus-Liebig-University Gießen, 35390 Gießen, Germany
| | - Alexander Sczyrba
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany; Faculty of Technology, Bielefeld University, 33615 Bielefeld, Germany
| | - Helmut König
- Institute of Microbiology and Wine Research, Johannes Gutenberg University Mainz, 55122 Mainz, Germany
| | - Alfred Pühler
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany
| | - Andreas Schlüter
- Center for Biotechnology, Bielefeld University, 33615 Bielefeld, Germany.
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Peabody MA, Laird MR, Vlasschaert C, Lo R, Brinkman FSL. PSORTdb: expanding the bacteria and archaea protein subcellular localization database to better reflect diversity in cell envelope structures. Nucleic Acids Res 2015; 44:D663-8. [PMID: 26602691 PMCID: PMC4702898 DOI: 10.1093/nar/gkv1271] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/03/2015] [Indexed: 01/01/2023] Open
Abstract
Protein subcellular localization (SCL) is important for understanding protein function, genome annotation, and has practical applications such as identification of potential vaccine components or diagnostic/drug targets. PSORTdb (http://db.psort.org) comprises manually curated SCLs for proteins which have been experimentally verified (ePSORTdb), as well as pre-computed SCL predictions for deduced proteomes from bacterial and archaeal complete genomes available from NCBI (cPSORTdb). We now report PSORTdb 3.0. It features improvements increasing user-friendliness, and further expands both ePSORTdb and cPSORTdb with a focus on improving protein SCL data in cases where it is most difficult—proteins associated with non-classical Gram-positive/Gram-negative/Gram-variable cell envelopes. ePSORTdb data curation was expanded, including adding in additional cell envelope localizations, and incorporating markers for cPSORTdb to automatically computationally identify if new genomes to be analysed fall into certain atypical cell envelope categories (i.e. Deinococcus-Thermus, Thermotogae, Corynebacteriales/Corynebacterineae, including Mycobacteria). The number of predicted proteins in cPSORTdb has increased from 3 700 000 when PSORTdb 2.0 was released to over 13 000 000 currently. PSORTdb 3.0 will be of wider use to researchers studying a greater diversity of monoderm or diderm microbes, including medically, agriculturally and industrially important species that have non-classical outer membranes or other cell envelope features.
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Affiliation(s)
- Michael A Peabody
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada
| | - Matthew R Laird
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada
| | - Caitlyn Vlasschaert
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Raymond Lo
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada
| | - Fiona S L Brinkman
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada
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Pollo SM, Zhaxybayeva O, Nesbø CL. Insights into thermoadaptation and the evolution of mesophily from the bacterial phylum Thermotogae. Can J Microbiol 2015. [DOI: 10.1139/cjm-2015-0073] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Thermophiles are extremophiles that grow optimally at temperatures >45 °C. To survive and maintain function of their biological molecules, they have a suite of characteristics not found in organisms that grow at moderate temperature (mesophiles). At the cellular level, thermophiles have mechanisms for maintaining their membranes, nucleic acids, and other cellular structures. At the protein level, each of their proteins remains stable and retains activity at temperatures that would denature their mesophilic homologs. Conversely, cellular structures and proteins from thermophiles may not function optimally at moderate temperatures. These differences between thermophiles and mesophiles presumably present a barrier for evolutionary transitioning between the 2 lifestyles. Therefore, studying closely related thermophiles and mesophiles can help us determine how such lifestyle transitions may happen. The bacterial phylum Thermotogae contains hyperthermophiles, thermophiles, mesophiles, and organisms with temperature ranges wide enough to span both thermophilic and mesophilic temperatures. Genomic, proteomic, and physiological differences noted between other bacterial thermophiles and mesophiles are evident within the Thermotogae. We argue that the Thermotogae is an ideal group of organisms for understanding of the response to fluctuating temperature and of long-term evolutionary adaptation to a different growth temperature range.
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Affiliation(s)
- Stephen M.J. Pollo
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, AB T6G 2E9, Canada
| | - Olga Zhaxybayeva
- Department of Biological Sciences and Department of Computer Science, Dartmouth College, 78 College Street, Hanover, NH 03755, USA
| | - Camilla L. Nesbø
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, AB T6G 2E9, Canada
- Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, P.O. Box 1066 Blindern, 0316 Oslo, Norway
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Eram MS, Sarafuddin B, Gong F, Ma K. Characterization of acetohydroxyacid synthase from the hyperthermophilic bacterium Thermotoga maritima. Biochem Biophys Rep 2015; 4:89-97. [PMID: 29124191 PMCID: PMC5668897 DOI: 10.1016/j.bbrep.2015.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 08/24/2015] [Accepted: 08/24/2015] [Indexed: 11/30/2022] Open
Abstract
Acetohydroxyacid synthase (AHAS) is the key enzyme in branched chain amino acid biosynthesis pathway. The enzyme activity and properties of a highly thermostable AHAS from the hyperthermophilic bacterium Thermotoga maritima is being reported. The catalytic and regulatory subunits of AHAS from T. maritima were over-expressed in Escherichia coli. The recombinant subunits were purified using a simplified procedure including a heat-treatment step followed by chromatography. A discontinuous colorimetric assay method was optimized and used to determine the kinetic parameters. AHAS activity was determined to be present in several Thermotogales including T. maritima. The catalytic subunit of T. maritima AHAS was purified approximately 30-fold, with an AHAS activity of approximately 160±27 U/mg and native molecular mass of 156±6 kDa. The regulatory subunit was purified to homogeneity and showed no catalytic activity as expected. The optimum pH and temperature for AHAS activity were 7.0 and 85 °C, respectively. The apparent Km and Vmax for pyruvate were 16.4±2 mM and 246±7 U/mg, respectively. Reconstitution of the catalytic and regulatory subunits led to increased AHAS activity. This is the first report on characterization of an isoleucine, leucine, and valine operon (ilv operon) enzyme from a hyperthermophilic microorganism and may contribute to our understanding of the physiological pathways in Thermotogales. The enzyme represents the most active and thermostable AHAS reported so far. First report of AHAS from a hyperthermophilic bacterium. Catalytic and regulatory subunits of AHAS of T. maritima was expressed in E. coli. Recombinant proteins were purified using a simplified procedure. Enzyme represents the most active and thermostable AHAS reported so far. Kinetic parameters were determined for the purified recombinant enzyme
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Key Words
- AHAS, acetohydroxyacid synthase
- Acetohydroxyacid synthase
- BCAA, branched chain amino acid
- Branched-chain amino acids
- CCE, crude cell extract
- CFE, cell-free extract
- HTCCE, heat-treated crude cell extract
- Hyperthermophiles
- IB, inclusion body
- IMAC, immobilized metal affinity chromatography
- TPP, thiamine pyrophosphate
- Thermotogales
- TmAHAS, Thermotoga maritima acetohydroxyacid synthase
- ilv, isoleucine, leucine, valine
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Affiliation(s)
- Mohammad S Eram
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Benozir Sarafuddin
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Frank Gong
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Kesen Ma
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
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Goux X, Calusinska M, Lemaigre S, Marynowska M, Klocke M, Udelhoven T, Benizri E, Delfosse P. Microbial community dynamics in replicate anaerobic digesters exposed sequentially to increasing organic loading rate, acidosis, and process recovery. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:122. [PMID: 26288654 PMCID: PMC4539856 DOI: 10.1186/s13068-015-0309-9] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 08/07/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND Volatile fatty acid intoxication (acidosis), a common process failure recorded in anaerobic reactors, leads to drastic losses in methane production. Unfortunately, little is known about the microbial mechanisms underlining acidosis and the potential to recover the process. In this study, triplicate mesophilic anaerobic reactors of 100 L were exposed to acidosis resulting from an excessive feeding with sugar beet pulp and were compared to a steady-state reactor. RESULTS Stable operational conditions at the beginning of the experiment initially led to similar microbial populations in the four reactors, as revealed by 16S rRNA gene T-RFLP and high-throughput amplicon sequencing. Bacteroidetes and Firmicutes were the two dominant phyla, and although they were represented by a high number of operational taxonomic units, only a few were dominant. Once the environment became deterministic (selective pressure from an increased substrate feeding), microbial populations started to diverge between the overfed reactors. Interestingly, most of bacteria and archaea showed redundant functional adaptation to the changing environmental conditions. However, the dominant Bacteroidales were resistant to high volatile fatty acids content and low pH. The severe acidosis did not eradicate archaea and a clear shift in archaeal populations from acetotrophic to hydrogenotrophic methanogenesis occurred in the overfed reactors. After 11 days of severe acidosis (pH 5.2 ± 0.4), the process was quickly recovered (restoration of the biogas production with methane content above 50 %) in the overfed reactors, by adjusting the pH to around 7 using NaOH and NaHCO3. CONCLUSIONS In this study we show that once the replicate reactors are confronted with sub-optimal conditions, their microbial populations start to evolve differentially. Furthermore the alterations of commonly used microbial parameters to monitor the process, such as richness, evenness and diversity indices were unsuccessful to predict the process failure. At the same time, we tentatively propose the replacement of the dominant Methanosaeta sp. in this case by Methanoculleus sp., to be a potential warning indicator of acidosis.
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Affiliation(s)
- Xavier Goux
- />Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, 4422 Belvaux, Luxembourg
- />Laboratoire Sols et Environnement, UMR 1120, Université de Lorraine, 2 avenue de la Forêt de Haye, TSA 40602, 54518 Vandœuvre-lès-Nancy, France
- />Laboratoire Sols et Environnement, UMR 1120, INRA, 2 avenue de la Forêt de Haye, TSA 40602, 54518 Vandœuvre-lès-Nancy, France
| | - Magdalena Calusinska
- />Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, 4422 Belvaux, Luxembourg
| | - Sébastien Lemaigre
- />Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, 4422 Belvaux, Luxembourg
| | - Martyna Marynowska
- />Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, 4422 Belvaux, Luxembourg
| | - Michael Klocke
- />Department Bioengineering, Leibniz Institute for Agricultural Engineering Potsdam-Bornim, Max-Eyth-Allee 100, 14469 Potsdam, Germany
| | - Thomas Udelhoven
- />Fachbereich VI- Raum- und Umweltwissenschaften, Umweltfernerkundung & Geoinformatik, Universität Trier, 54286 Trier, Germany
| | - Emile Benizri
- />Laboratoire Sols et Environnement, UMR 1120, Université de Lorraine, 2 avenue de la Forêt de Haye, TSA 40602, 54518 Vandœuvre-lès-Nancy, France
- />Laboratoire Sols et Environnement, UMR 1120, INRA, 2 avenue de la Forêt de Haye, TSA 40602, 54518 Vandœuvre-lès-Nancy, France
| | - Philippe Delfosse
- />Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, 4422 Belvaux, Luxembourg
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Adaptive Evolution of Thermotoga maritima Reveals Plasticity of the ABC Transporter Network. Appl Environ Microbiol 2015; 81:5477-85. [PMID: 26048924 DOI: 10.1128/aem.01365-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 05/28/2015] [Indexed: 01/16/2023] Open
Abstract
Thermotoga maritima is a hyperthermophilic anaerobe that utilizes a vast network of ABC transporters to efficiently metabolize a variety of carbon sources to produce hydrogen. For unknown reasons, this organism does not metabolize glucose as readily as it does glucose di- and polysaccharides. The leading hypothesis implicates the thermolability of glucose at the physiological temperatures at which T. maritima lives. After a 25-day laboratory evolution, phenotypes were observed with growth rates up to 1.4 times higher than and glucose utilization rates exceeding 50% those of the wild type. Genome resequencing revealed mutations in evolved cultures related to glucose-responsive ABC transporters. The native glucose ABC transporter, GluEFK, has more abundant transcripts either as a result of gene duplication-amplification or through mutations to the operator sequence regulating this operon. Conversely, BglEFGKL, a transporter of beta-glucosides, is substantially downregulated due to a nonsense mutation to the solute binding protein or due to a deletion of the upstream promoter. Analysis of the ABC2 uptake porter families for carbohydrate and peptide transport revealed that the solute binding protein, often among the transcripts detected at the highest levels, is predominantly downregulated in the evolved cultures, while the membrane-spanning domain and nucleotide binding components are less varied. Similar trends were observed in evolved strains grown on glycerol, a substrate that is not dependent on ABC transporters. Therefore, improved growth on glucose is achieved through mutations favoring GluEFK expression over BglEFGKL, and in lieu of carbon catabolite repression, the ABC transporter network is modulated to achieve improved growth fitness.
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38
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Maus I, Cibis KG, Wibberg D, Winkler A, Stolze Y, König H, Pühler A, Schlüter A. Complete genome sequence of the strain Defluviitoga tunisiensis L3, isolated from a thermophilic, production-scale biogas plant. J Biotechnol 2015; 203:17-8. [DOI: 10.1016/j.jbiotec.2015.03.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 03/11/2015] [Indexed: 11/29/2022]
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Blumer-Schuette SE, Brown SD, Sander KB, Bayer EA, Kataeva I, Zurawski JV, Conway JM, Adams MWW, Kelly RM. Thermophilic lignocellulose deconstruction. FEMS Microbiol Rev 2014; 38:393-448. [DOI: 10.1111/1574-6976.12044] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 08/20/2013] [Accepted: 08/28/2013] [Indexed: 11/28/2022] Open
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40
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Members of the Order Thermotogales: From Microbiology to Hydrogen Production. MICROBIAL BIOENERGY: HYDROGEN PRODUCTION 2014. [DOI: 10.1007/978-94-017-8554-9_9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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41
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Bareither CA, Wolfe GL, McMahon KD, Benson CH. Microbial diversity and dynamics during methane production from municipal solid waste. WASTE MANAGEMENT (NEW YORK, N.Y.) 2013; 33:1982-1992. [PMID: 23318155 DOI: 10.1016/j.wasman.2012.12.013] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 12/13/2012] [Accepted: 12/14/2012] [Indexed: 06/01/2023]
Abstract
The objectives of this study were to characterize development of bacterial and archaeal populations during biodegradation of municipal solid waste (MSW) and to link specific methanogens to methane generation. Experiments were conducted in three 0.61-m-diameter by 0.90-m-tall laboratory reactors to simulate MSW bioreactor landfills. Pyrosequencing of 16S rRNA genes was used to characterize microbial communities in both leachate and solid waste. Microbial assemblages in effluent leachate were similar between reactors during peak methane generation. Specific groups within the Bacteroidetes and Thermatogae phyla were present in all samples and were particularly abundant during peak methane generation. Microbial communities were not similar in leachate and solid fractions assayed at the end of reactor operation; solid waste contained a more abundant bacterial community of cellulose-degrading organisms (e.g., Firmicutes). Specific methanogen populations were assessed using quantitative polymerase chain reaction. Methanomicrobiales, Methanosarcinaceae, and Methanobacteriales were the predominant methanogens in all reactors, with Methanomicrobiales consistently the most abundant. Methanogen growth phases coincided with accelerated methane production, and cumulative methane yield increased with increasing total methanogen abundance. The difference in methanogen populations and corresponding methane yield is attributed to different initial cellulose and hemicellulose contents of the MSW. Higher initial cellulose and hemicellulose contents supported growth of larger methanogen populations that resulted in higher methane yield.
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Affiliation(s)
- Christopher A Bareither
- Civil & Environmental Engineering, Colorado State University, Ft. Collins, CO 80532, USA; Geological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
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Rodionov DA, Rodionova IA, Li X, Ravcheev DA, Tarasova Y, Portnoy VA, Zengler K, Osterman AL. Transcriptional regulation of the carbohydrate utilization network in Thermotoga maritima. Front Microbiol 2013; 4:244. [PMID: 23986752 PMCID: PMC3750489 DOI: 10.3389/fmicb.2013.00244] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 07/31/2013] [Indexed: 01/01/2023] Open
Abstract
Hyperthermophilic bacteria from the Thermotogales lineage can produce hydrogen by fermenting a wide range of carbohydrates. Previous experimental studies identified a large fraction of genes committed to carbohydrate degradation and utilization in the model bacterium Thermotoga maritima. Knowledge of these genes enabled comprehensive reconstruction of biochemical pathways comprising the carbohydrate utilization network. However, transcriptional factors (TFs) and regulatory mechanisms driving this network remained largely unknown. Here, we used an integrated approach based on comparative analysis of genomic and transcriptomic data for the reconstruction of the carbohydrate utilization regulatory networks in 11 Thermotogales genomes. We identified DNA-binding motifs and regulons for 19 orthologous TFs in the Thermotogales. The inferred regulatory network in T. maritima contains 181 genes encoding TFs, sugar catabolic enzymes and ABC-family transporters. In contrast to many previously described bacteria, a transcriptional regulation strategy of Thermotoga does not employ global regulatory factors. The reconstructed regulatory network in T. maritima was validated by gene expression profiling on a panel of mono- and disaccharides and by in vitro DNA-binding assays. The observed upregulation of genes involved in catabolism of pectin, trehalose, cellobiose, arabinose, rhamnose, xylose, glucose, galactose, and ribose showed a strong correlation with the UxaR, TreR, BglR, CelR, AraR, RhaR, XylR, GluR, GalR, and RbsR regulons. Ultimately, this study elucidated the transcriptional regulatory network and mechanisms controlling expression of carbohydrate utilization genes in T. maritima. In addition to improving the functional annotations of associated transporters and catabolic enzymes, this research provides novel insights into the evolution of regulatory networks in Thermotogales.
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Affiliation(s)
- Dmitry A Rodionov
- Sanford-Burnham Medical Research Institute La Jolla, CA, USA ; A. A. Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences Moscow, Russia
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The genome organization of Thermotoga maritima reflects its lifestyle. PLoS Genet 2013; 9:e1003485. [PMID: 23637642 PMCID: PMC3636130 DOI: 10.1371/journal.pgen.1003485] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 03/13/2013] [Indexed: 01/01/2023] Open
Abstract
The generation of genome-scale data is becoming more routine, yet the subsequent analysis of omics data remains a significant challenge. Here, an approach that integrates multiple omics datasets with bioinformatics tools was developed that produces a detailed annotation of several microbial genomic features. This methodology was used to characterize the genome of Thermotoga maritima—a phylogenetically deep-branching, hyperthermophilic bacterium. Experimental data were generated for whole-genome resequencing, transcription start site (TSS) determination, transcriptome profiling, and proteome profiling. These datasets, analyzed in combination with bioinformatics tools, served as a basis for the improvement of gene annotation, the elucidation of transcription units (TUs), the identification of putative non-coding RNAs (ncRNAs), and the determination of promoters and ribosome binding sites. This revealed many distinctive properties of the T. maritima genome organization relative to other bacteria. This genome has a high number of genes per TU (3.3), a paucity of putative ncRNAs (12), and few TUs with multiple TSSs (3.7%). Quantitative analysis of promoters and ribosome binding sites showed increased sequence conservation relative to other bacteria. The 5′UTRs follow an atypical bimodal length distribution comprised of “Short” 5′UTRs (11–17 nt) and “Common” 5′UTRs (26–32 nt). Transcriptional regulation is limited by a lack of intergenic space for the majority of TUs. Lastly, a high fraction of annotated genes are expressed independent of growth state and a linear correlation of mRNA/protein is observed (Pearson r = 0.63, p<2.2×10−16 t-test). These distinctive properties are hypothesized to be a reflection of this organism's hyperthermophilic lifestyle and could yield novel insights into the evolutionary trajectory of microbial life on earth. Genomic studies have greatly benefited from the advent of high-throughput technologies and bioinformatics tools. Here, a methodology integrating genome-scale data and bioinformatics tools is developed to characterize the genome organization of the hyperthermophilic, phylogenetically deep-branching bacterium Thermotoga maritima. This approach elucidates several features of the genome organization and enables comparative analysis of these features across diverse taxa. Our results suggest that the genome of T. maritima is reflective of its hyperthermophilic lifestyle. Ultimately, constraints imposed on the genome have negative impacts on regulatory complexity and phenotypic diversity. Investigating the genome organization of Thermotogae species will help resolve various causal factors contributing to the genome organization such as phylogeny and environment. Applying a similar analysis of the genome organization to numerous taxa will likely provide insights into microbial evolution.
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Rodionova IA, Leyn SA, Burkart MD, Boucher N, Noll KM, Osterman AL, Rodionov DA. Novel inositol catabolic pathway inThermotoga maritima. Environ Microbiol 2013; 15:2254-66. [DOI: 10.1111/1462-2920.12096] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Revised: 01/18/2013] [Accepted: 01/20/2013] [Indexed: 11/30/2022]
Affiliation(s)
| | - Semen A. Leyn
- A. A. Kharkevich Institute for Information Transmission Problems; Russian Academy of Sciences; Moscow; 127994; Russia
| | - Michael D. Burkart
- Department of Chemistry and Biochemistry; University of California San Diego; La Jolla; CA; 92093; USA
| | - Nathalie Boucher
- Department of Molecular and Cell Biology; University of Connecticut; Storrs; CT; 06269; USA
| | - Kenneth M. Noll
- Department of Molecular and Cell Biology; University of Connecticut; Storrs; CT; 06269; USA
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Abstract
Extremely thermophilic microorganisms have been sources of thermostable and thermoactive enzymes for over 30 years. However, information and insights gained from genome sequences, in conjunction with new tools for molecular genetics, have opened up exciting new possibilities for biotechnological opportunities based on extreme thermophiles that go beyond single-step biotransformations. Although the pace for discovering novel microorganisms has slowed over the past two decades, genome sequence data have provided clues to novel biomolecules and metabolic pathways, which can be mined for a range of new applications. Furthermore, recent advances in molecular genetics for extreme thermophiles have made metabolic engineering for high temperature applications a reality.
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Affiliation(s)
- Andrew D Frock
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905
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The temperature dependent proteomic analysis of Thermotoga maritima. PLoS One 2012; 7:e46463. [PMID: 23071576 PMCID: PMC3465335 DOI: 10.1371/journal.pone.0046463] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 08/30/2012] [Indexed: 11/21/2022] Open
Abstract
Thermotoga maritima (T. maritima) is a typical thermophile, and its proteome response to environmental temperature changes has yet to be explored. This study aims to uncover the temperature-dependent proteins of T. maritima using comparative proteomic approach. T. maritima was cultured under four temperatures, 60°C, 70°C, 80°C and 90°C, and the bacterial proteins were extracted and electrophoresed in two-dimensional mode. After analysis of gel images, a total of 224 spots, either cytoplasm or membrane, were defined as temperature-dependent. Of these spots, 75 unique bacterial proteins were identified using MALDI TOF/TOF MS. As is well known, the chaperone proteins such as heat shock protein 60 and elongation factor Tu, were up-regulated in abundance due to increased temperature. However, several temperature-dependent proteins of T. maritima responded very differently when compared to responses of the thermophile T. tengcongensis. Intriguingly, a number of proteins involved in central carbohydrate metabolism were significantly up-regulated at higher temperature. Their corresponding mRNA levels were elevated accordingly. The increase in abundance of several key enzymes indicates that a number of central carbohydrate metabolism pathways of T. maritima are activated at higher temperatures.
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Rodionova IA, Scott DA, Grishin NV, Osterman AL, Rodionov DA. Tagaturonate-fructuronate epimerase UxaE, a novel enzyme in the hexuronate catabolic network in Thermotoga maritima. Environ Microbiol 2012; 14:2920-34. [PMID: 22925190 DOI: 10.1111/j.1462-2920.2012.02856.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 07/22/2012] [Accepted: 07/23/2012] [Indexed: 11/28/2022]
Abstract
Thermotoga maritima is a marine hyperthermophilic microorganism that degrades a wide range of simple and complex carbohydrates including pectin and produces fermentative hydrogen at high yield. Galacturonate and glucuronate, two abundant hexuronic acids in pectin and xylan, respectively, are catabolized via committed metabolic pathways to supply carbon and energy for a variety of microorganisms. By a combination of bioinformatics and experimental techniques we identified a novel enzyme family (named UxaE) catalysing a previously unknown reaction in the hexuronic acid catabolic pathway, epimerization of tagaturonate to fructuronate. The enzymatic activity of the purified recombinant tagaturonate epimerase from T. maritima was directly confirmed and kinetically characterized. Its function was also confirmed by genetic complementation of the growth of the Escherichia coli uxaB knockout mutant strain on galacturonate. An inferred novel galacturonate to mannonate catabolic pathway in T. maritima was reconstituted in vitro using a mixture of recombinant purified enzymes UxaE, UxaC and UxuB. Members of the newly identified UxaE family were identified in ~50 phylogenetically diverse heterotrophic bacteria from aquatic and soil environments. The genomic context of respective genes and reconstruction of associated pathways suggest that UxaE enzymatic and biological function remains conserved in all of these species.
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Affiliation(s)
- Irina A Rodionova
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
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48
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Abstract
Sugar phosphorylation is an indispensable committed step in a large variety of sugar catabolic pathways, which are major suppliers of carbon and energy in heterotrophic species. Specialized sugar kinases that are indispensable for most of these pathways can be utilized as signature enzymes for the reconstruction of carbohydrate utilization machinery from microbial genomic and metagenomic data. Sugar kinases occur in several structurally distinct families with various partially overlapping as well as yet unknown substrate specificities that often cannot be accurately assigned by homology-based techniques. A subsystems-based metabolic reconstruction combined with the analysis of genome context and followed by experimental testing of predicted gene functions is a powerful approach of functional gene annotation. Here we applied this integrated approach for functional mapping of all sugar kinases constituting an extensive and diverse sugar kinome in the thermophilic bacterium Thermotoga maritima. Substrate preferences of 14 kinases mainly from the FGGY and PfkB families were inferred by bioinformatics analysis and biochemically characterized by screening with a panel of 45 different carbohydrates. Most of the analyzed enzymes displayed narrow substrate preferences corresponding to their predicted physiological roles in their respective catabolic pathways. The observed consistency supports the choice of kinases as signature enzymes for genomics-based identification and reconstruction of sugar utilization pathways. Use of the integrated genomic and experimental approach greatly speeds up the identification of the biochemical function of unknown proteins and improves the quality of reconstructed pathways.
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Bhandari V, Naushad HS, Gupta RS. Protein based molecular markers provide reliable means to understand prokaryotic phylogeny and support Darwinian mode of evolution. Front Cell Infect Microbiol 2012; 2:98. [PMID: 22919687 PMCID: PMC3417386 DOI: 10.3389/fcimb.2012.00098] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 06/27/2012] [Indexed: 11/20/2022] Open
Abstract
The analyses of genome sequences have led to the proposal that lateral gene transfers (LGTs) among prokaryotes are so widespread that they disguise the interrelationships among these organisms. This has led to questioning of whether the Darwinian model of evolution is applicable to prokaryotic organisms. In this review, we discuss the usefulness of taxon-specific molecular markers such as conserved signature indels (CSIs) and conserved signature proteins (CSPs) for understanding the evolutionary relationships among prokaryotes and to assess the influence of LGTs on prokaryotic evolution. The analyses of genomic sequences have identified large numbers of CSIs and CSPs that are unique properties of different groups of prokaryotes ranging from phylum to genus levels. The species distribution patterns of these molecular signatures strongly support a tree-like vertical inheritance of the genes containing these molecular signatures that is consistent with phylogenetic trees. Recent detailed studies in this regard on the Thermotogae and Archaea, which are reviewed here, have identified large numbers of CSIs and CSPs that are specific for the species from these two taxa and a number of their major clades. The genetic changes responsible for these CSIs (and CSPs) initially likely occurred in the common ancestors of these taxa and then vertically transferred to various descendants. Although some CSIs and CSPs in unrelated groups of prokaryotes were identified, their small numbers and random occurrence has no apparent influence on the consistent tree-like branching pattern emerging from other markers. These results provide evidence that although LGT is an important evolutionary force, it does not mask the tree-like branching pattern of prokaryotes or understanding of their evolutionary relationships. The identified CSIs and CSPs also provide novel and highly specific means for identification of different groups of microbes and for taxonomical and biochemical studies.
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Affiliation(s)
- Vaibhav Bhandari
- Department of Biochemistry and Biomedical Sciences, McMaster University Hamilton, ON, Canada
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50
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Schut GJ, Boyd ES, Peters JW, Adams MWW. The modular respiratory complexes involved in hydrogen and sulfur metabolism by heterotrophic hyperthermophilic archaea and their evolutionary implications. FEMS Microbiol Rev 2012; 37:182-203. [PMID: 22713092 DOI: 10.1111/j.1574-6976.2012.00346.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 05/30/2012] [Accepted: 06/08/2012] [Indexed: 12/01/2022] Open
Abstract
Hydrogen production is a vital metabolic process for many anaerobic organisms, and the enzyme responsible, hydrogenase, has been studied since the 1930s. A novel subfamily with unique properties was recently recognized, represented by the 14-subunit membrane-bound [NiFe] hydrogenase from the archaeon Pyrococcus furiosus. This so-called energy-converting hydrogenase links the thermodynamically favorable oxidation of ferredoxin with the formation of hydrogen and conserves energy in the form of an ion gradient. It is therefore a simple respiratory system within a single complex. This hydrogenase shows a modular composition represented by a Na(+)/H(+) antiporter domain (Mrp) and a [NiFe] hydrogenase domain (Mbh). An analysis of the large number of microbial genome sequences available shows that homologs of Mbh and Mrp tend to be clustered within the genomes of a limited number of archaeal and bacterial species. In several instances, additional genes are associated with the Mbh and Mrp gene clusters that encode proteins that catalyze the oxidation of formate, CO or NAD(P)H. The Mbh complex also shows extensive homology to a number of subunits within the NADH quinone oxidoreductase or complex I family. The respiratory-type membrane-bound hydrogenase complex appears to be closely related to the common ancestor of complex I and [NiFe] hydrogenases in general.
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Affiliation(s)
- Gerrit J Schut
- Department of Biochemistry & Molecular Biology, University of Georgia, Athens, GA 30602, USA
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