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Gregory SP, Mackie JRM, Barnett MJ. Radioactive waste microbiology: predicting microbial survival and activity in changing extreme environments. FEMS Microbiol Rev 2024; 48:fuae001. [PMID: 38216518 PMCID: PMC10853057 DOI: 10.1093/femsre/fuae001] [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: 07/31/2023] [Revised: 12/01/2023] [Accepted: 01/11/2024] [Indexed: 01/14/2024] Open
Abstract
The potential for microbial activity to occur within the engineered barrier system (EBS) of a geological disposal facility (GDF) for radioactive waste is acknowledged by waste management organizations as it could affect many aspects of the safety functions of a GDF. Microorganisms within an EBS will be exposed to changing temperature, pH, radiation, salinity, saturation, and availability of nutrient and energy sources, which can limit microbial survival and activity. Some of the limiting conditions are incorporated into GDF designs for safety reasons, including the high pH of cementitious repositories, the limited pore space of bentonite-based repositories, or the high salinity of GDFs in evaporitic geologies. Other environmental conditions such as elevated radiation, temperature, and desiccation, arise as a result of the presence of high heat generating waste (HHGW). Here, we present a comprehensive review of how environmental conditions in the EBS may limit microbial activity, covering HHGW and lower heat generating waste (LHGW) in a range of geological environments. We present data from the literature on the currently recognized limits to life for each of the environmental conditions described above, and nutrient availability to establish the potential for life in these environments. Using examples where each variable has been modelled for a particular GDF, we outline the times and locations when that variable can be expected to limit microbial activity. Finally, we show how this information for multiple variables can be used to improve our understanding of the potential for microbial activity to occur within the EBS of a GDF and, more broadly, to understand microbial life in changing environments exposed to multiple extreme conditions.
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Affiliation(s)
- Simon P Gregory
- British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG, United Kingdom
| | - Jessica R M Mackie
- British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG, United Kingdom
| | - Megan J Barnett
- British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG, United Kingdom
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2
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Jia W, Cheng L, Tan Q, Liu Y, Dou J, Yang K, Yang Q, Wang S, Li J, Niu G, Zheng L, Ding A. Response of the soil microbial community to petroleum hydrocarbon stress shows a threshold effect: research on aged realistic contaminated fields. Front Microbiol 2023; 14:1188229. [PMID: 37389339 PMCID: PMC10301742 DOI: 10.3389/fmicb.2023.1188229] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 05/22/2023] [Indexed: 07/01/2023] Open
Abstract
Introduction Microbes play key roles in maintaining soil ecological functions. Petroleum hydrocarbon contamination is expected to affect microbial ecological characteristics and the ecological services they provide. In this study, the multifunctionalities of contaminated and uncontaminated soils in an aged petroleum hydrocarbon-contaminated field and their correlation with soil microbial characteristics were analyzed to explore the effect of petroleum hydrocarbons on soil microbes. Methods Soil physicochemical parameters were determined to calculate soil multifunctionalities. In addition, 16S high-throughput sequencing technology and bioinformation analysis were used to explore microbial characteristics. Results The results indicated that high concentrations of petroleum hydrocarbons (565-3,613 mg•kg-1, high contamination) reduced soil multifunctionality, while low concentrations of petroleum hydrocarbons (13-408 mg•kg-1, light contamination) might increase soil multifunctionality. In addition, light petroleum hydrocarbon contamination increased the richness and evenness of microbial community (p < 0.01), enhanced the microbial interactions and widened the niche breadth of keystone genus, while high petroleum hydrocarbon contamination reduced the richness of the microbial community (p < 0.05), simplified the microbial co-occurrence network, and increased the niche overlap of keystone genus. Conclusion Our study demonstrates that light petroleum hydrocarbon contamination has a certain improvement effect on soil multifunctionalities and microbial characteristics. While high contamination shows an inhibitory effect on soil multifunctionalities and microbial characteristics, which has significance for the protection and management of petroleum hydrocarbon-contaminated soil.
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Affiliation(s)
- Wenjuan Jia
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Lirong Cheng
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Qiuyang Tan
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Yueqiao Liu
- Experiment and Practice Innovation Education Center, Beijing Normal University at Zhuhai, Zhuhai, China
| | - Junfeng Dou
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Kai Yang
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Qing Yang
- College of Water Sciences, Beijing Normal University, Beijing, China
- Beijing Geological Environment Monitoring Institute, Beijing, China
| | - Senjie Wang
- Beijing Municipal No.4 Construction Engineering Co., Ltd., Beijing, China
| | - Jing Li
- Beijing Municipal No.4 Construction Engineering Co., Ltd., Beijing, China
| | - Geng Niu
- Beijing Municipal No.4 Construction Engineering Co., Ltd., Beijing, China
| | - Lei Zheng
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Aizhong Ding
- College of Water Sciences, Beijing Normal University, Beijing, China
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Milojevic T, Cramm MA, Hubert CRJ, Westall F. "Freezing" Thermophiles: From One Temperature Extreme to Another. Microorganisms 2022; 10:microorganisms10122417. [PMID: 36557670 PMCID: PMC9782878 DOI: 10.3390/microorganisms10122417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/23/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022] Open
Abstract
New detections of thermophiles in psychrobiotic (i.e., bearing cold-tolerant life forms) marine and terrestrial habitats including Arctic marine sediments, Antarctic accretion ice, permafrost, and elsewhere are continually being reported. These microorganisms present great opportunities for microbial ecologists to examine biogeographical processes for spore-formers and non-spore-formers alike, including dispersal histories connecting warm and cold biospheres. In this review, we examine different examples of thermophiles in cryobiotic locations, and highlight exploration of thermophiles at cold temperatures under laboratory conditions. The survival of thermophiles in psychrobiotic environments provokes novel considerations of physiological and molecular mechanisms underlying natural cryopreservation of microorganisms. Cultures of thermophiles maintained at low temperature may serve as a non-sporulating laboratory model for further exploration of metabolic potential of thermophiles at psychrobiotic temperatures, as well as for elucidating molecular mechanisms behind natural preservation and adaptation to psychrobiotic environments. These investigations are highly relevant for the search for life on other cold and icy planets in the Solar System, such as Mars, Europa and Enceladus.
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Affiliation(s)
- Tetyana Milojevic
- Exobiology Group, CNRS-Centre de Biophysique Moléculaire, University of Orléans, Rue Charles Sadron, CEDEX 2, 45071 Orléans, France
- Correspondence: ; Tel.: +33-2-3825-5548
| | - Margaret Anne Cramm
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Casey R. J. Hubert
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Frances Westall
- Exobiology Group, CNRS-Centre de Biophysique Moléculaire, Rue Charles Sadron, CEDEX 2, 45071 Orléans, France
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Bell E, Rattray JE, Sloan K, Sherry A, Pilloni G, Hubert CRJ. Hyperthermophilic endospores germinate and metabolize organic carbon in sediments heated to 80°C. Environ Microbiol 2022; 24:5534-5545. [PMID: 36100999 PMCID: PMC9826295 DOI: 10.1111/1462-2920.16167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 08/10/2022] [Indexed: 01/11/2023]
Abstract
Cold surface sediments host a seedbank of functionally diverse thermophilic bacteria. These thermophiles are present as endospores, which are widely dispersed in aquatic environments. Here, we investigated the functional potential of endospore populations in cold surface sediments heated to 80°C. Microbial production of acetate was observed at 80°C and could be enhanced by supplying additional organic carbon substrates. Comparison of 16S rRNA gene amplicon libraries from 80°C enrichments to sediments heated to lower temperatures (50-70°C) showed that temperature selects for distinct populations of endospore-forming bacteria. Whereas sulfate-reducing thermophiles were enriched in 50-70°C incubations, 80°C exceeds their thermal tolerance and selects for hyperthermophilic organotrophic bacteria that are similarly detected in amplicon libraries from sediments heated to 90°C. Genome-resolved metagenomics revealed novel carbon cycling members of Symbiobacteriales, Thermosediminibacteraceae, Thermanaeromonas and Calditerricola with the genomic potential for the degradation of carbohydrates, sugars, amino acids and nucleotides. Endospores of thermophilic bacteria are deposited on seabed sediments worldwide where they remain dormant as they are buried in the accumulating sediments. Our results suggest that endospore populations could be activated by temperature increases encountered during burial and show the potential for organotrophic metabolic activity contributing to acetate generation in deep hot sediments.
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Affiliation(s)
- Emma Bell
- Geomicrobiology Group, Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada,School of Natural and Environmental SciencesNewcastle UniversityNewcastle upon TyneUK
| | - Jayne E. Rattray
- Geomicrobiology Group, Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
| | - Kathryn Sloan
- Geomicrobiology Group, Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
| | - Angela Sherry
- Hub for Biotechnology in the Built Environment, Department of Applied SciencesNorthumbria UniversityNewcastle upon TyneUK
| | - Giovanni Pilloni
- ExxonMobil Technology and Engineering CompanyAnnandaleNew JerseyUSA
| | - Casey R. J. Hubert
- Geomicrobiology Group, Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada,School of Natural and Environmental SciencesNewcastle UniversityNewcastle upon TyneUK
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Rattray JE, Chakraborty A, Elizondo G, Ellefson E, Bernard B, Brooks J, Hubert CRJ. Endospores associated with deep seabed geofluid features in the eastern Gulf of Mexico. GEOBIOLOGY 2022; 20:823-836. [PMID: 35993193 PMCID: PMC9804197 DOI: 10.1111/gbi.12517] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 05/12/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Recent studies have reported up to 1.9 × 1029 bacterial endospores in the upper kilometre of deep subseafloor marine sediments, however, little is understood about their origin and dispersal. In cold ocean environments, the presence of thermospores (endospores produced by thermophilic bacteria) suggests that distribution is governed by passive migration from warm anoxic sources possibly facilitated by geofluid flow, such as advective hydrocarbon seepage sourced from petroleum deposits deeper in the subsurface. This study assesses this hypothesis by measuring endospore abundance and distribution across 60 sites in Eastern Gulf of Mexico (EGM) sediments using a combination of the endospore biomarker 2,6-pyridine dicarboxylic acid or 'dipicolinic acid' (DPA), sequencing 16S rRNA genes of thermospores germinated in 50°C sediment incubations, petroleum geochemistry in the sediments and acoustic seabed data from sub-bottom profiling. High endospore abundance is associated with geologically active conduit features (mud volcanoes, pockmarks, escarpments and fault systems), consistent with subsurface fluid flow dispersing endospores from deep warm sources up into the cold ocean. Thermospores identified at conduit sites were most closely related to bacteria associated with the deep biosphere habitats including hydrocarbon systems. The high endospore abundance at geological seep features demonstrated here suggests that recalcitrant endospores and their chemical components (such as DPA) can be used in concert with geochemical and geophysical analyses to locate discharging seafloor features. This multiproxy approach can be used to better understand patterns of advective fluid flow in regions with complex geology like the EGM basin.
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Affiliation(s)
- Jayne E. Rattray
- Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
| | - Anirban Chakraborty
- Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
- Department of Biological SciencesIdaho State UniversityPocatelloIdahoUSA
| | - Gretta Elizondo
- Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
| | - Emily Ellefson
- Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
- Geological SciencesStanford UniversityStanfordCaliforniaUSA
| | | | | | - Casey R. J. Hubert
- Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
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Chakraborty A, Rattray JE, Drake SS, Matthews S, Li C, Jørgensen BB, Hubert CRJ. Metabolic responses of thermophilic endospores to sudden heat-induced perturbation in marine sediment samples. Front Microbiol 2022; 13:958417. [PMID: 36033870 PMCID: PMC9411986 DOI: 10.3389/fmicb.2022.958417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 07/19/2022] [Indexed: 11/13/2022] Open
Abstract
Microbially mediated processes in a given habitat tend to be catalyzed by abundant populations that are ecologically adapted to exploit specific environmental characteristics. Typically, metabolic activities of rare populations are limited but may be stimulated in response to acute environmental stressors. Community responses to sudden changes in temperature and pressure can include suppression and activation of different populations, but these dynamics remain poorly understood. The permanently cold ocean floor hosts countless low-abundance microbes including endospores of thermophilic bacteria. Incubating sediments at high temperature resuscitates viable spores, causing the proliferation of bacterial populations. This presents a tractable system for investigating changes in a microbiome's community structure in response to dramatic environmental perturbations. Incubating permanently cold Arctic fjord sediments at 50°C for 216 h with and without volatile fatty acid amendment provoked major changes in community structure. Germination of thermophilic spores from the sediment rare biosphere was tracked using mass spectrometry-based metabolomics, radiotracer-based sulfate reduction rate measurements, and high-throughput 16S rRNA gene sequencing. Comparing community similarity at different intervals of the incubations showed distinct temporal shifts in microbial populations, depending on organic substrate amendment. Metabolite patterns indicated that amino acids and other sediment-derived organics were decomposed by fermentative Clostridia within the first 12–48 h. This fueled early and late phases of exponential increases in sulfate reduction, highlighting the cross-feeding of volatile fatty acids as electron donors for different sulfate-reducing Desulfotomaculia populations. The succession of germinated endospores triggered by sudden exposure to high temperature and controlled by nutrient availability offers a model for understanding the ecological response of dormant microbial communities following major environmental perturbations.
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Affiliation(s)
- Anirban Chakraborty
- Department of Biological Sciences, Idaho State University, Pocatello, ID, United States
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
- *Correspondence: Anirban Chakraborty
| | - Jayne E. Rattray
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Sienna S. Drake
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Stuart Matthews
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Carmen Li
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Bo Barker Jørgensen
- Section for Microbiology, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Casey R. J. Hubert
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
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Degradation of biological macromolecules supports uncultured microbial populations in Guaymas Basin hydrothermal sediments. THE ISME JOURNAL 2021; 15:3480-3497. [PMID: 34112968 PMCID: PMC8630151 DOI: 10.1038/s41396-021-01026-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 02/05/2023]
Abstract
Hydrothermal sediments contain large numbers of uncultured heterotrophic microbial lineages. Here, we amended Guaymas Basin sediments with proteins, polysaccharides, nucleic acids or lipids under different redox conditions and cultivated heterotrophic thermophiles with the genomic potential for macromolecule degradation. We reconstructed 20 metagenome-assembled genomes (MAGs) of uncultured lineages affiliating with known archaeal and bacterial phyla, including endospore-forming Bacilli and candidate phylum Marinisomatota. One Marinisomatota MAG had 35 different glycoside hydrolases often in multiple copies, seven extracellular CAZymes, six polysaccharide lyases, and multiple sugar transporters. This population has the potential to degrade a broad spectrum of polysaccharides including chitin, cellulose, pectin, alginate, chondroitin, and carrageenan. We also describe thermophiles affiliating with the genera Thermosyntropha, Thermovirga, and Kosmotoga with the capability to make a living on nucleic acids, lipids, or multiple macromolecule classes, respectively. Several populations seemed to lack extracellular enzyme machinery and thus likely scavenged oligo- or monomers (e.g., MAGs affiliating with Archaeoglobus) or metabolic products like hydrogen (e.g., MAGs affiliating with Thermodesulfobacterium or Desulforudaceae). The growth of methanogens or the production of methane was not observed in any condition, indicating that the tested macromolecules are not degraded into substrates for methanogenesis in hydrothermal sediments. We provide new insights into the niches, and genomes of microorganisms that actively degrade abundant necromass macromolecules under oxic, sulfate-reducing, and fermentative thermophilic conditions. These findings improve our understanding of the carbon flow across trophic levels and indicate how primary produced biomass sustains complex and productive ecosystems.
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Long-Term Biocide Efficacy and Its Effect on a Souring Microbial Community. Appl Environ Microbiol 2021; 87:e0084221. [PMID: 34160245 PMCID: PMC8357289 DOI: 10.1128/aem.00842-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Reservoir souring, which is the production of H2S mainly by sulfate-reducing microorganisms (SRM) in oil reservoirs, has been a long-standing issue for the oil industry. While biocides have been frequently applied to control biogenic souring, the effects of biocide treatment are usually temporary, and biocides eventually fail. The reasons for biocide failure and the long-term response of the microbial community remain poorly understood. In this study, one-time biocide treatments with glutaraldehyde (GA) and an aldehyde-releasing biocide (ARB) at low (100 ppm) and high (750 ppm) doses were individually applied to a complex SRM community, followed by 1 year of monitoring of the chemical responses and the microbial community succession. The chemical results showed that souring control failed after 7 days at a dose of 100 ppm regardless of the biocide type and lasting souring control for the entire 1-year period was achieved only with ARB at 750 ppm. Microbial community analyses suggested that the high-dose biocide treatments resulted in 1 order of magnitude lower average total microbial abundance and average SRM abundance, compared to the low-dose treatments. The recurrence of souring was associated with reduction of alpha diversity and with long-term microbial community structure changes; therefore, monitoring changes in microbial community metrics may provide early warnings of the failure of a biocide-based souring control program in the field. Furthermore, spore-forming sulfate reducers (Desulfotomaculum and Desulfurispora) were enriched and became dominant in both GA-treated groups, which could cause challenges for the design of long-lasting remedial souring control strategies. IMPORTANCE Reservoir souring is a problem for the oil and gas industry, because H2S corrodes the steel infrastructure, downgrades oil quality, and poses substantial risks to field personnel and the environment. Biocides have been widely applied to remedy souring, but the long-term performance of biocide treatments is hard to predict or to optimize due to limited understanding of the microbial ecology affected by biocide treatment. This study investigates the long-term biocide performance and associated changes in the abundance, diversity, and structure of the souring microbial community, thus advancing the knowledge toward a deeper understanding of the microbial ecology of biocide-treated systems and contributing to the improvement of current biocide-based souring control practices. The study showcases the potential application of incorporating microbial community analyses to forecast souring, and it highlights the long-term consequences of biocide treatment in the microbial communities, with relevance to both operators and regulators.
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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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Rattray JE, Chakraborty A, Li C, Elizondo G, John N, Wong M, Radović JR, Oldenburg TBP, Hubert CRJ. Sensitive quantification of dipicolinic acid from bacterial endospores in soils and sediments. Environ Microbiol 2020; 23:1397-1406. [PMID: 33264453 PMCID: PMC8048543 DOI: 10.1111/1462-2920.15343] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 11/30/2020] [Indexed: 11/27/2022]
Abstract
Endospore-forming bacteria make up an important and numerically significant component of microbial communities in a range of settings including soils, industry, hospitals and marine sediments extending into the deep subsurface. Bacterial endospores are non-reproductive structures that protect DNA and improve cell survival during periods unfavourable for bacterial growth. An important determinant of endospores withstanding extreme environmental conditions is 2,6-pyridine dicarboxylic acid (i.e. dipicolinic acid, or DPA), which contributes heat resistance. This study presents an improved HPLC-fluorescence method for DPA quantification using a single 10-min run with pre-column Tb3+ chelation. Relative to existing DPA quantification methods, specific improvements pertain to sensitivity, detection limit and range, as well as the development of new free DPA and spore-specific DPA proxies. The method distinguishes DPA from intact and recently germinated spores, enabling responses to germinants in natural samples or experiments to be assessed in a new way. DPA-based endospore quantification depends on accurate spore-specific DPA contents, in particular, thermophilic spores are shown to have a higher DPA content, meaning that marine sediments with plentiful thermophilic spores may require spore number estimates to be revisited. This method has a wide range of potential applications for more accurately quantifying bacterial endospores in diverse environmental samples.
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Affiliation(s)
- Jayne E Rattray
- Department of Biological Sciences, University of Calgary, Calgary, T2N 1N4, Canada
| | - Anirban Chakraborty
- Department of Biological Sciences, University of Calgary, Calgary, T2N 1N4, Canada
| | - Carmen Li
- Department of Biological Sciences, University of Calgary, Calgary, T2N 1N4, Canada
| | - Gretta Elizondo
- Department of Biological Sciences, University of Calgary, Calgary, T2N 1N4, Canada
| | - Nisha John
- Department of Biological Sciences, University of Calgary, Calgary, T2N 1N4, Canada
| | - Michelle Wong
- Department of Biological Sciences, University of Calgary, Calgary, T2N 1N4, Canada
| | - Jagoš R Radović
- Department of Geoscience, University of Calgary, Calgary, T2N 1N4, Canada
| | | | - Casey R J Hubert
- Department of Biological Sciences, University of Calgary, Calgary, T2N 1N4, Canada
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