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Wang T, Li X, Wang H, Xue G, Zhou M, Ran X, Wang Y. Sulfur autotrophic denitrification as an efficient nitrogen removals method for wastewater treatment towards lower organic requirement: A review. WATER RESEARCH 2023; 245:120569. [PMID: 37683522 DOI: 10.1016/j.watres.2023.120569] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/29/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023]
Abstract
The sulfur autotrophic denitrification (SADN) process is an organic-free denitrification process that utilizes reduced inorganic sulfur compounds (RISCs) as the electron donor for nitrate reduction. It has been proven to be a cost-effective and environment-friendly approach to achieving carbon neutrality in wastewater treatment plants. However, there is no consensus on whether SADN can become a dominant denitrification process to treat domestic wastewater or industrial wastewater if organic carbon is desired to be saved. Through a comprehensive summary of the SADN process and extensive discussion of state-of-the-art SADN-based technologies, this review provides a systematic overview of the potential of the SADN process as a sustainable alternative for the heterotrophic denitrification (HD) process (organic carbons as electron donor). First, we introduce the mechanism of the SADN process that is different from the HD process, including its transformation pathways based on different RISCs as well as functional bacteria and key enzymes. The SADN process has unique theoretical advantages (e.g., economy and carbon-free, less greenhouse gas emissions, and a great potential for coupling with novel autotrophic processes), even if there are still some potential issues (e.g., S intermediates undesired production, and relatively slow growth rate of sulfur-oxidizing bacteria [SOB]) for wastewater treatment. Then we present the current representative SADN-based technologies, and propose the outlooks for future research in regards to SADN process, including implement of coupling of SADN with other nitrogen removal processes (e.g., HD, and sulfate-dependent anaerobic ammonium oxidation), and formation of SOB-enriched biofilm. This review will provide guidance for the future applications of the SADN process to ensure a robust-performance and chemical-saving denitrification for wastewater treatment.
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Affiliation(s)
- Tong Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Xiang Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, China
| | - Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China.
| | - Gang Xue
- College of Environmental Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620, China
| | - Mingda Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Xiaochuan Ran
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai 200092, China.
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Trotter VV, Shatsky M, Price MN, Juba TR, Zane GM, De León KB, Majumder ELW, Gui Q, Ali R, Wetmore KM, Kuehl JV, Arkin AP, Wall JD, Deutschbauer AM, Chandonia JM, Butland GP. Large-scale genetic characterization of the model sulfate-reducing bacterium, Desulfovibrio vulgaris Hildenborough. Front Microbiol 2023; 14:1095191. [PMID: 37065130 PMCID: PMC10102598 DOI: 10.3389/fmicb.2023.1095191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/10/2023] [Indexed: 04/03/2023] Open
Abstract
Sulfate-reducing bacteria (SRB) are obligate anaerobes that can couple their growth to the reduction of sulfate. Despite the importance of SRB to global nutrient cycles and their damage to the petroleum industry, our molecular understanding of their physiology remains limited. To systematically provide new insights into SRB biology, we generated a randomly barcoded transposon mutant library in the model SRB Desulfovibrio vulgaris Hildenborough (DvH) and used this genome-wide resource to assay the importance of its genes under a range of metabolic and stress conditions. In addition to defining the essential gene set of DvH, we identified a conditional phenotype for 1,137 non-essential genes. Through examination of these conditional phenotypes, we were able to make a number of novel insights into our molecular understanding of DvH, including how this bacterium synthesizes vitamins. For example, we identified DVU0867 as an atypical L-aspartate decarboxylase required for the synthesis of pantothenic acid, provided the first experimental evidence that biotin synthesis in DvH occurs via a specialized acyl carrier protein and without methyl esters, and demonstrated that the uncharacterized dehydrogenase DVU0826:DVU0827 is necessary for the synthesis of pyridoxal phosphate. In addition, we used the mutant fitness data to identify genes involved in the assimilation of diverse nitrogen sources and gained insights into the mechanism of inhibition of chlorate and molybdate. Our large-scale fitness dataset and RB-TnSeq mutant library are community-wide resources that can be used to generate further testable hypotheses into the gene functions of this environmentally and industrially important group of bacteria.
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Affiliation(s)
- Valentine V. Trotter
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Maxim Shatsky
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Morgan N. Price
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Thomas R. Juba
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
| | - Grant M. Zane
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
| | - Kara B. De León
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, United States
| | - Erica L.-W. Majumder
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, United States
| | - Qin Gui
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
| | - Rida Ali
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Kelly M. Wetmore
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Jennifer V. Kuehl
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Adam P. Arkin
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, United States
| | - Judy D. Wall
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
| | - Adam M. Deutschbauer
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
| | - John-Marc Chandonia
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Gareth P. Butland
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
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Dou L, Zhang M, Pan L, Liu L, Su Z. Sulfide removal characteristics, pathways and potential application of a novel chemolithotrophic sulfide-oxidizing strain, Marinobacter sp. SDSWS8. ENVIRONMENTAL RESEARCH 2022; 212:113176. [PMID: 35364039 DOI: 10.1016/j.envres.2022.113176] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/14/2022] [Accepted: 03/22/2022] [Indexed: 05/27/2023]
Abstract
Sulfide generally exists in wastewater, black and odor river, as well as aquaculture water, and give rise to adverse effect on ecological stability and biological safety, due to the toxicity, corrosivity and malodor of sulfide. In the present study, a chemolithotrophic sulfide-oxidizing bacteria (SOB) was isolated and identified as Marinobacter maroccanus strain SDSWS8. And it produced no hemolysin and was susceptible to most antibiotics. There were no accumulation of sulfide, sulfate and thiosulfate during the sulfide removal process. The optimum conditions of sulfide removal were temperature 15-40 °C, initial pH value 4.5-9.5, salinity 10-40‰, C/N ratio 0-20 and sulfide concentration 25-150 mg/L. The key genes of sulfide oxidation, Sox system (soxB, soxX, soxA, soxZ, soxY, soxD, soxC), dissimilatory sulfur oxidation (dsrA, aprA and sat) and sqr, were successfully amplified and expressed, indicating the three pathways coordinated to complete the sulfide oxidation. Besides, strain SDSWS8 had inhibitory effect on four pathogen Vibrio (V. harveyi, V. parahaemolyticus, V. anguillarum and V. splendidus). Furthermore, efficient removal of sulfide from real aquaculture water and sludge mixture could be accomplished by strain SDSWS8. This study may provide a promising candidate strain for sulfide-rich water treatment.
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Affiliation(s)
- Le Dou
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, 266003, China
| | - Mengyu Zhang
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, 266003, China
| | - Luqing Pan
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, 266003, China.
| | - Liping Liu
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, 266003, China
| | - Zhaopeng Su
- The Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, 266003, China
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Carlson HK, Youngblut MD, Redford SA, Williamson AJ, Coates JD. Sulfate adenylyl transferase kinetics and mechanisms of metabolic inhibitors of microbial sulfate respiration. ISME COMMUNICATIONS 2021; 1:67. [PMID: 37938298 PMCID: PMC9723548 DOI: 10.1038/s43705-021-00069-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 10/15/2021] [Accepted: 10/20/2021] [Indexed: 11/09/2023]
Abstract
Sulfate analog oxyanions that function as selective metabolic inhibitors of dissimilatory sulfate reducing microorganisms (SRM) are widely used in ecological studies and industrial applications. As such, it is important to understand the mode of action and mechanisms of tolerance or adaptation to these compounds. Different oxyanions vary widely in their inhibitory potency and mechanism of inhibition, but current evidence suggests that the sulfate adenylyl transferase/ATP sulfurylase (Sat) enzyme is an important target. We heterologously expressed and purified the Sat from the model SRM, Desulfovibrio alaskensis G20. With this enzyme we determined the turnover kinetics (kcat, KM) for alternative substrates (molybdate, selenate, arsenate, monofluorophosphate, and chromate) and inhibition constants (KI) for competitive inhibitors (perchlorate, chlorate, and nitrate). These measurements enable the first quantitative comparisons of these compounds as substrates or inhibitors of a purified Sat from a respiratory sulfate reducer. We compare predicted half-maximal inhibitory concentrations (IC50) based on Sat kinetics with measured IC50 values against D. alaskensis G20 growth and discuss our results in light of known mechanisms of sensitivity or resistance to oxyanions. This analysis helps with the interpretation of recent adaptive laboratory evolution studies and illustrates the value of interpreting gene-microbe-environment interactions through the lens of enzyme kinetics.
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Affiliation(s)
- Hans K Carlson
- Energy & Biosciences Institute, University of California, Berkeley, Berkeley, CA, 94720, USA.
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA, 94704, USA.
| | - Matthew D Youngblut
- Energy & Biosciences Institute, University of California, Berkeley, Berkeley, CA, 94720, USA
- Twist Bioscience, 681 Gateway Blvd, South San Francisco, CA, 94080, USA
| | - Steven A Redford
- Energy & Biosciences Institute, University of California, Berkeley, Berkeley, CA, 94720, USA
- Graduate Program in Biophysical Sciences, The University of Chicago, Chicago, IL, USA
| | - Adam J Williamson
- Energy & Biosciences Institute, University of California, Berkeley, Berkeley, CA, 94720, USA
- CENBG, Université de Bordeaux, CNRS-IN2P3/, 19 Chemin du Solarium, CS10120, 33175, Gradignan, France
| | - John D Coates
- Energy & Biosciences Institute, University of California, Berkeley, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, 94720, USA
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5
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Marietou A. Sulfate reducing microorganisms in high temperature oil reservoirs. ADVANCES IN APPLIED MICROBIOLOGY 2021; 116:99-131. [PMID: 34353505 DOI: 10.1016/bs.aambs.2021.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
High temperature reservoirs offer a window into the microbial life of the deep biosphere. Sulfate reducing microorganisms have been recovered from high temperature oil reservoirs around the globe and characterized using culture-dependent and culture-independent approaches. The activities of sulfate reducers contribute to reservoir souring and hydrocarbon degradation among other attracting considerable interest from the oil industry for the last 100 years. The extremes of temperature and pressure shape the activities and distribution of sulfate reducing bacteria and archaea in high temperature reservoirs. This chapter will attempt to summarize the key findings on the diversity and activities of sulfate reducing microorganisms in high temperature reservoirs.
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Affiliation(s)
- Angeliki Marietou
- Section for Microbiology, Department of Biology, Aarhus University, Aarhus, Denmark.
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Lui LM, Majumder ELW, Smith HJ, Carlson HK, von Netzer F, Fields MW, Stahl DA, Zhou J, Hazen TC, Baliga NS, Adams PD, Arkin AP. Mechanism Across Scales: A Holistic Modeling Framework Integrating Laboratory and Field Studies for Microbial Ecology. Front Microbiol 2021; 12:642422. [PMID: 33841364 PMCID: PMC8024649 DOI: 10.3389/fmicb.2021.642422] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/22/2021] [Indexed: 11/13/2022] Open
Abstract
Over the last century, leaps in technology for imaging, sampling, detection, high-throughput sequencing, and -omics analyses have revolutionized microbial ecology to enable rapid acquisition of extensive datasets for microbial communities across the ever-increasing temporal and spatial scales. The present challenge is capitalizing on our enhanced abilities of observation and integrating diverse data types from different scales, resolutions, and disciplines to reach a causal and mechanistic understanding of how microbial communities transform and respond to perturbations in the environment. This type of causal and mechanistic understanding will make predictions of microbial community behavior more robust and actionable in addressing microbially mediated global problems. To discern drivers of microbial community assembly and function, we recognize the need for a conceptual, quantitative framework that connects measurements of genomic potential, the environment, and ecological and physical forces to rates of microbial growth at specific locations. We describe the Framework for Integrated, Conceptual, and Systematic Microbial Ecology (FICSME), an experimental design framework for conducting process-focused microbial ecology studies that incorporates biological, chemical, and physical drivers of a microbial system into a conceptual model. Through iterative cycles that advance our understanding of the coupling across scales and processes, we can reliably predict how perturbations to microbial systems impact ecosystem-scale processes or vice versa. We describe an approach and potential applications for using the FICSME to elucidate the mechanisms of globally important ecological and physical processes, toward attaining the goal of predicting the structure and function of microbial communities in chemically complex natural environments.
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Affiliation(s)
- Lauren M. Lui
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Erica L.-W. Majumder
- Department of Bacteriology, University of Wisconsin–Madison, Madison, WI, United States
| | - Heidi J. Smith
- Center for Biofilm Engineering, Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Hans K. Carlson
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Frederick von Netzer
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States
| | - Matthew W. Fields
- Center for Biofilm Engineering, Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - David A. Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology & Plant Biology, School of Civil Engineering and Environmental Sciences, University of Oklahoma, Norman, OK, United States
| | - Terry C. Hazen
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, Knoxville, TN, United States
| | | | - Paul D. Adams
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, United States
| | - Adam P. Arkin
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, United States
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Williamson AJ, Engelbrektson AL, Liu Y, Huang LL, Kumar A, Menon AR, Thieme J, Carlson HK, Coates JD. Tungstate Control of Microbial Sulfidogenesis and Souring of the Engineered Environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:16119-16127. [PMID: 33253556 DOI: 10.1021/acs.est.0c04682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Sulfide accumulation in oil reservoir fluids (souring) from the activity of sulfate-reducing microorganisms (SRM) is of grave concern because of the associated health and facility failure risks. Here, we present an assessment of tungstate as a selective and potent inhibitor of SRM. Dose-response inhibitor experiments were conducted with a number of SRM isolates and enrichments at 30-80 °C and an increase in the effectiveness of tungstate treatment at higher temperatures was observed. To explore mixed inhibitor treatment modes, we tested synergy or antagonism between several inhibitors with tungstate, and found synergism between WO42- and NO2-, while additive effects were observed with ClO4- and NO3-. We also evaluated SRM inhibition by tungstate in advective upflow oil-sand-packed columns. Although 2 mM tungstate was initially sufficient to inhibit sulfidogenesis, subsequent temporal CaWO4 precipitation resulted in loss of the bioavailable inhibitor from solution and a concurrent increase in effluent sulfide. Mixing 4 mM sodium carbonate with the 2 mM tungstate was enough to promote tungstate solubility to reach inhibitory concentrations, without precipitation, and completely inhibit SRM activity. Overall, we demonstrate the effectiveness of tungstate as a potent SRM inhibitor, particularly at higher temperatures, and propose a novel carbonate-tungstate formulation for application to soured oil reservoirs.
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Affiliation(s)
- Adam J Williamson
- Energy Biosciences Institute, 2151 Berkeley Way, California 94704, United States
| | - Anna L Engelbrektson
- Energy Biosciences Institute, 2151 Berkeley Way, California 94704, United States
| | - Yi Liu
- Energy Biosciences Institute, 2151 Berkeley Way, California 94704, United States
| | - Leah L Huang
- Energy Biosciences Institute, 2151 Berkeley Way, California 94704, United States
| | - Aarti Kumar
- Energy Biosciences Institute, 2151 Berkeley Way, California 94704, United States
| | - Aruna R Menon
- Energy Biosciences Institute, 2151 Berkeley Way, California 94704, United States
| | - Juergen Thieme
- NSLS-II Brookhaven National Laboratory, Brookhaven, New York 11973, United States
| | - Hans K Carlson
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - John D Coates
- Energy Biosciences Institute, 2151 Berkeley Way, California 94704, United States
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Experimental evolution reveals nitrate tolerance mechanisms in Desulfovibrio vulgaris. ISME JOURNAL 2020; 14:2862-2876. [PMID: 32934357 DOI: 10.1038/s41396-020-00753-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 08/09/2020] [Accepted: 08/17/2020] [Indexed: 11/08/2022]
Abstract
Elevated nitrate in the environment inhibits sulfate reduction by important microorganisms of sulfate-reducing bacteria (SRB). Several SRB may respire nitrate to survive under elevated nitrate, but how SRB that lack nitrate reductase survive to elevated nitrate remains elusive. To understand nitrate adaptation mechanisms, we evolved 12 populations of a model SRB (i.e., Desulfovibrio vulgaris Hildenborough, DvH) under elevated NaNO3 for 1000 generations, analyzed growth and acquired mutations, and linked their genotypes with phenotypes. Nitrate-evolved (EN) populations significantly (p < 0.05) increased nitrate tolerance, and whole-genome resequencing identified 119 new mutations in 44 genes of 12 EN populations, among which six functional gene groups were discovered with high mutation frequencies at the population level. We observed a high frequency of nonsense or frameshift mutations in nitrosative stress response genes (NSR: DVU2543, DVU2547, and DVU2548), nitrogen regulatory protein C family genes (NRC: DVU2394-2396, DVU2402, and DVU2405), and nitrate cluster (DVU0246-0249 and DVU0251). Mutagenesis analysis confirmed that loss-of-functions of NRC and NSR increased nitrate tolerance. Also, functional gene groups involved in fatty acid synthesis, iron regulation, and two-component system (LytR/LytS) known to be responsive to multiple stresses, had a high frequency of missense mutations. Mutations in those gene groups could increase nitrate tolerance through regulating energy metabolism, barring entry of nitrate into cells, altering cell membrane characteristics, or conferring growth advantages at the stationary phase. This study advances our understanding of nitrate tolerance mechanisms and has important implications for linking genotypes with phenotypes in DvH.
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Li W, Cheng C, Cao G, Ren N. Enhanced biohydrogen production from sugarcane molasses by adding Ginkgo biloba leaves. BIORESOURCE TECHNOLOGY 2020; 298:122523. [PMID: 31830657 DOI: 10.1016/j.biortech.2019.122523] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 11/27/2019] [Accepted: 11/28/2019] [Indexed: 06/10/2023]
Abstract
Low H2 yield from biomass impedes the industrial application of biohydrogen production. To improve H2 yield, the effect of Ginkgo biloba leaf (GL) on H2 production was investigated in this study. In batch fermentation with sugarcane molasses (SM), the addition of GL improved H2 yield by 28.03%. SM medium was optimized with response surface methodology (RSM) to determine the best concentrations of GL, SM, and an inexpensive nitrogen source-corn steep liquor (CSL). A maximum yield of 1.58 mol-H2/mol-hexose from SM was obtained when GL, CSL and SM hexose were 2.31 g/L, 2.28 g/L and 10 g/L, respectively. As observed with metabolic flux analysis, GL enhanced H2 conversion from SM via altering the metabolic flux distribution of E. harbinense from ethanol pathway towards acetate pathway. This study demonstrated the promotion effect of GL on H2 production from SM, raising a novel method for enhanced biohydrogen production in large scales.
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Affiliation(s)
- Weiming Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Chi Cheng
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China
| | - Guangli Cao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
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10
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Anion transport as a target of adaption to perchlorate in sulfate-reducing communities. ISME JOURNAL 2019; 14:450-462. [PMID: 31659234 DOI: 10.1038/s41396-019-0540-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/04/2019] [Accepted: 09/12/2019] [Indexed: 11/09/2022]
Abstract
Inhibitors can be used to control the functionality of microbial communities by targeting specific metabolisms. The targeted inhibition of dissimilatory sulfate reduction limits the generation of toxic and corrosive hydrogen sulfide across several industrial systems. Sulfate-reducing microorganisms (SRM) are specifically inhibited by sulfate analogs, such as perchlorate. Previously, we showed pure culture SRM adaptation to perchlorate stress through mutation of the sulfate adenylyltransferase, a central enzyme in the sulfate reduction pathway. Here, we explored adaptation to perchlorate across unconstrained SRM on a community scale. We followed natural and bio-augmented sulfidogenic communities through serial transfers in increasing concentrations of perchlorate. Our results demonstrated that perchlorate stress altered community structure by initially selecting for innately more resistant strains. Isolation, whole-genome sequencing, and molecular biology techniques allowed us to define subsequent genetic mechanisms of adaptation that arose across the dominant adapting SRM. Changes in the regulation of divalent anion:sodium symporter family transporters led to increased intracellular sulfate to perchlorate ratios, allowing SRM to escape the effects of competitive inhibition. Thus, in contrast to pure-culture results, SRM in communities cope with perchlorate stress via changes in anion transport and its regulation. This highlights the value of probing evolutionary questions in an ecological framework, bridging the gap between ecology, evolution, genomics, and physiology.
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