1
|
Imminger S, Meier DV, Schintlmeister A, Legin A, Schnecker J, Richter A, Gillor O, Eichorst SA, Woebken D. Survival and rapid resuscitation permit limited productivity in desert microbial communities. Nat Commun 2024; 15:3056. [PMID: 38632260 DOI: 10.1038/s41467-024-46920-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 03/13/2024] [Indexed: 04/19/2024] Open
Abstract
Microbial activity in drylands tends to be confined to rare and short periods of rain. Rapid growth should be key to the maintenance of ecosystem processes in such narrow activity windows, if desiccation and rehydration cause widespread cell death due to osmotic stress. Here, simulating rain with 2H2O followed by single-cell NanoSIMS, we show that biocrust microbial communities in the Negev Desert are characterized by limited productivity, with median replication times of 6 to 19 days and restricted number of days allowing growth. Genome-resolved metatranscriptomics reveals that nearly all microbial populations resuscitate within minutes after simulated rain, independent of taxonomy, and invest their activity into repair and energy generation. Together, our data reveal a community that makes optimal use of short activity phases by fast and universal resuscitation enabling the maintenance of key ecosystem functions. We conclude that desert biocrust communities are highly adapted to surviving rapid changes in soil moisture and solute concentrations, resulting in high persistence that balances limited productivity.
Collapse
Affiliation(s)
- Stefanie Imminger
- Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
- University of Vienna, Doctoral School in Microbiology and Environmental Science, Vienna, Austria
| | - Dimitri V Meier
- Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
- Department of Ecological Microbiology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Arno Schintlmeister
- Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
- Large-Instrument Facility for Environmental and Isotope Mass Spectrometry, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Anton Legin
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Vienna, Austria
| | - Jörg Schnecker
- Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Andreas Richter
- Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Midreshet Ben Gurion, Israel
| | - Stephanie A Eichorst
- Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Dagmar Woebken
- Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria.
| |
Collapse
|
2
|
Han P, Tang X, Koch H, Dong X, Hou L, Wang D, Zhao Q, Li Z, Liu M, Lücker S, Shi G. Unveiling unique microbial nitrogen cycling and nitrification driver in coastal Antarctica. Nat Commun 2024; 15:3143. [PMID: 38609359 PMCID: PMC11014942 DOI: 10.1038/s41467-024-47392-4] [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: 11/26/2023] [Accepted: 04/01/2024] [Indexed: 04/14/2024] Open
Abstract
Largely removed from anthropogenic delivery of nitrogen (N), Antarctica has notably low levels of nitrogen. Though our understanding of biological sources of ammonia have been elucidated, the microbial drivers of nitrate (NO3-) cycling in coastal Antarctica remains poorly understood. Here, we explore microbial N cycling in coastal Antarctica, unraveling the biological origin of NO3- via oxygen isotopes in soil and lake sediment, and through the reconstruction of 1968 metagenome-assembled genomes from 29 microbial phyla. Our analysis reveals the metabolic potential for microbial N2 fixation, nitrification, and denitrification, but not for anaerobic ammonium oxidation, signifying a unique microbial N-cycling dynamic. We identify the predominance of complete ammonia oxidizing (comammox) Nitrospira, capable of performing the entire nitrification process. Their adaptive strategies to the Antarctic environment likely include synthesis of trehalose for cold stress, high substrate affinity for resource utilization, and alternate metabolic pathways for nutrient-scarce conditions. We confirm the significant role of comammox Nitrospira in the autotrophic, nitrification process via 13C-DNA-based stable isotope probing. This research highlights the crucial contribution of nitrification to the N budget in coastal Antarctica, identifying comammox Nitrospira clade B as a nitrification driver.
Collapse
Affiliation(s)
- Ping Han
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
- Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Xiufeng Tang
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Hanna Koch
- Department of Microbiology, RIBES, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands
- Center for Health & Bioresources, Bioresources Unit, AIT Austrian Institute of Technology GmbH, A-3430, Tulln, Austria
| | - Xiyang Dong
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, China
- State Key Laboratory Breeding Base of Marine Genetic Resources, Xiamen, 361005, China
- Fujian Key Laboratory of Marine Genetic Resources, Xiamen, 361005, China
| | - Lijun Hou
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
- Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Danhe Wang
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Qian Zhao
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Zhe Li
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Min Liu
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
- Institute of Eco-Chongming (IEC), East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China.
| | - Sebastian Lücker
- Department of Microbiology, RIBES, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands
| | - Guitao Shi
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
| |
Collapse
|
3
|
Savaglia V, Lambrechts S, Tytgat B, Vanhellemont Q, Elster J, Willems A, Wilmotte A, Verleyen E, Vyverman W. Geology defines microbiome structure and composition in nunataks and valleys of the Sør Rondane Mountains, East Antarctica. Front Microbiol 2024; 15:1316633. [PMID: 38380088 PMCID: PMC10877063 DOI: 10.3389/fmicb.2024.1316633] [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: 10/10/2023] [Accepted: 01/09/2024] [Indexed: 02/22/2024] Open
Abstract
Understanding the relation between terrestrial microorganisms and edaphic factors in the Antarctic can provide insights into their potential response to environmental changes. Here we examined the composition of bacterial and micro-eukaryotic communities using amplicon sequencing of rRNA genes in 105 soil samples from the Sør Rondane Mountains (East Antarctica), differing in bedrock or substrate type and associated physicochemical conditions. Although the two most widespread taxa (Acidobacteriota and Chlorophyta) were relatively abundant in each sample, multivariate analysis and co-occurrence networks revealed pronounced differences in community structure depending on substrate type. In moraine substrates, Actinomycetota and Cercozoa were the most abundant bacterial and eukaryotic phyla, whereas on gneiss, granite and marble substrates, Cyanobacteriota and Metazoa were the dominant bacterial and eukaryotic taxa. However, at lower taxonomic level, a distinct differentiation was observed within the Cyanobacteriota phylum depending on substrate type, with granite being dominated by the Nostocaceae family and marble by the Chroococcidiopsaceae family. Surprisingly, metazoans were relatively abundant according to the 18S rRNA dataset, even in samples from the most arid sites, such as moraines in Austkampane and Widerøefjellet ("Dry Valley"). Overall, our study shows that different substrate types support distinct microbial communities, and that mineral soil diversity is a major determinant of terrestrial microbial diversity in inland Antarctic nunataks and valleys.
Collapse
Affiliation(s)
- Valentina Savaglia
- InBioS Research Unit, Department of Life Sciences, University of Liège, Liège, Belgium
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Ghent, Belgium
| | - Sam Lambrechts
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Ghent, Belgium
- Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Bjorn Tytgat
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Ghent, Belgium
| | | | - Josef Elster
- Faculty of Science, Centre for Polar Ecology, University of South Bohemia České Budějovice and Institute of Botany, Třeboň, Czechia
| | - Anne Willems
- Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Annick Wilmotte
- InBioS Research Unit, Department of Life Sciences, University of Liège, Liège, Belgium
| | - Elie Verleyen
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Ghent, Belgium
| | - Wim Vyverman
- Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Ghent, Belgium
| |
Collapse
|
4
|
Wang M, Sun H, Xu Z. Characterization of Rhizosphere Microbial Diversity and Selection of Plant-Growth-Promoting Bacteria at the Flowering and Fruiting Stages of Rapeseed. PLANTS (BASEL, SWITZERLAND) 2024; 13:329. [PMID: 38276786 PMCID: PMC10819753 DOI: 10.3390/plants13020329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024]
Abstract
Plant rhizosphere microorganisms play an important role in modulating plant growth and productivity. This study aimed to elucidate the diversity of rhizosphere microorganisms at the flowering and fruiting stages of rapeseed (Brassica napus). Microbial communities in rhizosphere soils were analyzed via high-throughput sequencing of 16S rRNA for bacteria and internal transcribed spacer (ITS) DNA regions for fungi. A total of 401 species of bacteria and 49 species of fungi in the rhizosphere soil samples were found in three different samples. The composition and diversity of rhizosphere microbial communities were significantly different at different stages of rapeseed growth. Plant-growth-promoting rhizobacteria (PGPRs) have been widely applied to improve plant growth, health, and production. Thirty-four and thirty-one PGPR strains were isolated from the rhizosphere soil samples collected at the flowering and fruiting stages of rapeseed, respectively. Different inorganic phosphorus- and silicate-solubilizing and auxin-producing capabilities were found in different strains, in addition to different heavy-metal resistances. This study deepens the understanding of the microbial diversity in the rapeseed rhizosphere and provides a microbial perspective of sustainable rapeseed cultivation.
Collapse
Affiliation(s)
- Mengjiao Wang
- School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong 723000, China;
- Collaborative Innovation Center for Comprehensive Development of Biological Resources in Qinling-Ba Mountains, Hanzhong 723000, China
- Shaanxi Key Laboratory Bioresources, Hanzhong 723000, China
| | - Haiyan Sun
- School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong 723000, China;
- Shaanxi Key Laboratory Bioresources, Hanzhong 723000, China
| | - Zhimin Xu
- School of Nutrition and Food Sciences, Louisiana State University, Baton Rouge, LA 70809, USA;
| |
Collapse
|
5
|
Garvin ZK, Abades SR, Trefault N, Alfaro FD, Sipes K, Lloyd KG, Onstott TC. Prevalence of trace gas-oxidizing soil bacteria increases with radial distance from Polloquere hot spring within a high-elevation Andean cold desert. THE ISME JOURNAL 2024; 18:wrae062. [PMID: 38625060 PMCID: PMC11094475 DOI: 10.1093/ismejo/wrae062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 01/29/2024] [Accepted: 04/10/2024] [Indexed: 04/17/2024]
Abstract
High-elevation arid regions harbor microbial communities reliant on metabolic niches and flexibility to survive under biologically stressful conditions, including nutrient limitation that necessitates the utilization of atmospheric trace gases as electron donors. Geothermal springs present "oases" of microbial activity, diversity, and abundance by delivering water and substrates, including reduced gases. However, it is unknown whether these springs exhibit a gradient of effects, increasing their impact on trace gas-oxidizers in the surrounding soils. We assessed whether proximity to Polloquere, a high-altitude geothermal spring in an Andean salt flat, alters the diversity and metabolic structure of nearby soil bacterial populations compared to the surrounding cold desert. Recovered DNA and metagenomic analyses indicate that the spring represents an oasis for microbes in this challenging environment, supporting greater biomass with more diverse metabolic functions in proximal soils that declines sharply with radial distance from the spring. Despite the sharp decrease in biomass, potential rates of atmospheric hydrogen (H2) and carbon monoxide (CO) uptake increase away from the spring. Kinetic estimates suggest this activity is due to high-affinity trace gas consumption, likely as a survival strategy for energy/carbon acquisition. These results demonstrate that Polloquere regulates a gradient of diverse microbial communities and metabolisms, culminating in increased activity of trace gas-oxidizers as the influence of the spring yields to that of the regional salt flat environment. This suggests the spring holds local importance within the context of the broader salt flat and potentially represents a model ecosystem for other geothermal systems in high-altitude desert environments.
Collapse
Affiliation(s)
- Zachary K Garvin
- Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
| | - Sebastián R Abades
- GEMA Center for Genomics, Ecology and Environment, Faculty of Interdisciplinary Studies, Universidad Mayor, 8580745, Santiago, Chile
| | - Nicole Trefault
- GEMA Center for Genomics, Ecology and Environment, Faculty of Interdisciplinary Studies, Universidad Mayor, 8580745, Santiago, Chile
| | - Fernando D Alfaro
- GEMA Center for Genomics, Ecology and Environment, Faculty of Interdisciplinary Studies, Universidad Mayor, 8580745, Santiago, Chile
| | - Katie Sipes
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark
| | - Karen G Lloyd
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
| | - Tullis C Onstott
- Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
| |
Collapse
|
6
|
Obayori OS, Adesina OD, Salam LB, Ashade AO, Nwaokorie FO. Depletion of hydrocarbons and concomitant shift in bacterial community structure of a diesel-spiked tropical agricultural soil. ENVIRONMENTAL TECHNOLOGY 2023:1-16. [PMID: 38118139 DOI: 10.1080/09593330.2023.2291421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/26/2023] [Indexed: 12/22/2023]
Abstract
Bacterial community of a diesel-spiked agricultural soil was monitored over a 42-day period using the metagenomic approach in order to gain insight into key phylotypes impacted by diesel contamination and be able to predict end point of bioattenuation. Soil physico-chemical parameters showed significant differences (P < 0.05) between the Polluted Soil (PS) and the Unpolluted control (US)across time points. After 21 days, the diesel content decreased by 27.39%, and at the end of 42 days, by 57.11%. Aromatics such as benzene, anthanthrene, propylbenzene, phenanthrenequinone, anthraquinone, and phenanthridine were degraded to non-detected levels within 42 days, while some medium range alkanes and polyaromatics such as acenaphthylene, naphthalene, and anthracene showed significant levels of degradation. After 21 days (LASTD21), there was a massive enrichment of the phylum Proteobacteria (72.94%), a slight decrease in the abundance of phylum Actinobacteriota (12.74%), and > 500% decrease in the abundance of the phylum Acidobacteriodota (5.26%). Day 42 (LASTD42) saw establishment of the dominance of the Proteobacteria (34.95%), Actinobacteriota, (21.71%), and Firmicutes (32.14%), and decimation of phyla such as Gemmatimonadota, Planctomycetota, and Verrucromicrobiota which play important roles in the cycling of elements and soil health. Principal component analysis showed that in PS moisture contents, phosphorus, nitrogen, organic carbon, had greater impacts on the community structure in LASTD21, while acidity, potassium, sodium, calcium and magnesium impacted the control sample. Recovery time of the soil based on the residual hydrocarbons at Day 42 was estimated to be 229.112 d. Thus, additional biostimulation may be required to achieve cleanup within one growing season.
Collapse
Affiliation(s)
| | | | - Lateef Babatunde Salam
- Microbiology Unit, Department of Biological Sciences, Elizade University, Ilara-Mokin, Nigeria
| | | | | |
Collapse
|
7
|
Han D, Richter-Heitmann T, Kim JH, Friedrich MW, Yin X, Elvert M, Ryu JS, Jang K, Nam SI. Influence of sedimentary deposition on the microbial assembly process in Arctic Holocene marine sediments. Front Microbiol 2023; 14:1231839. [PMID: 37700860 PMCID: PMC10493304 DOI: 10.3389/fmicb.2023.1231839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/15/2023] [Indexed: 09/14/2023] Open
Abstract
The sea-level rise during the Holocene (11-0 ky BP) and its resulting sedimentation and biogeochemical processes may control microbial life in Arctic sediments. To gain further insight into this interaction, we investigated a sediment core (up to 10.7 m below the seafloor) from the Chuckchi Shelf of the western Arctic Ocean using metabarcoding-based sequencing and qPCR to characterize archaeal and bacterial 16S rRNA gene composition and abundance, respectively. We found that Arctic Holocene sediments harbor local microbial communities, reflecting geochemical and paleoclimate separations. The composition of bacterial communities was more diverse than that of archaeal communities, and specifically distinct at the boundary layer of the sulfate-methane transition zone. Enriched cyanobacterial sequences in the Arctic middle Holocene (8-7 ky BP) methanogenic sediments remarkably suggest past cyanobacterial blooms. Bacterial communities were phylogenetically influenced by interactions between dispersal limitation and environmental selection governing community assembly under past oceanographic changes. The relative influence of stochastic and deterministic processes on the bacterial assemblage was primarily determined by dispersal limitation. We have summarized our findings in a conceptual model that revealed how changes in paleoclimate phases cause shifts in ecological succession and the assembly process. In this ecological model, dispersal limitation is an important driving force for progressive succession for bacterial community assembly processes on a geological timescale in the western Arctic Ocean. This enabled a better understanding of the ecological processes that drive the assembly of communities in Holocene sedimentary habitats affected by sea-level rise, such as in the shallow western Arctic shelves.
Collapse
Affiliation(s)
- Dukki Han
- Department of Marine Bioscience, Gangneung-Wonju National University, Gangneung-si, Gangwon-do, Republic of Korea
| | - Tim Richter-Heitmann
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
| | - Ji-Hoon Kim
- Marine Geology & Energy Division, Korea Institute of Geoscience and Mineral Resources, Daejeon, Republic of Korea
| | - Michael W. Friedrich
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Xiuran Yin
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Marcus Elvert
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Organic Geochemistry Group, Faculty of Geosciences, University of Bremen, Bremen, Germany
| | - Jong-Sik Ryu
- Department of Earth and Environmental Sciences, Pukyong National University, Busan, Republic of Korea
| | - Kwangchul Jang
- Division of Glacial Environment Research, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Seung-Il Nam
- Division of Glacial Environment Research, Korea Polar Research Institute, Incheon, Republic of Korea
| |
Collapse
|
8
|
Xu D, Yu X, Chen J, Liu H, Zheng Y, Qu H, Bao Y. Microbial Assemblages Associated with the Soil-Root Continuum of an Endangered Plant, Helianthemum songaricum Schrenk. Microbiol Spectr 2023; 11:e0338922. [PMID: 37222598 PMCID: PMC10269481 DOI: 10.1128/spectrum.03389-22] [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: 08/25/2022] [Accepted: 04/22/2023] [Indexed: 05/25/2023] Open
Abstract
The microbial network of the soil-root continuum plays a key role in plant growth. To date, limited information is available about the microbial assemblages in the rhizosphere and endosphere of endangered plants. We suspect that unknown microorganisms in roots and soil play an important role in the survival strategies of endangered plants. To address this research gap, we investigated the diversity and composition of the microbial communities of the soil-root continuum of the endangered shrub Helianthemum songaricum and observed that the microbial communities and structures of the rhizosphere and endosphere samples were distinguishable. The dominant rhizosphere bacteria were Actinobacteria (36.98%) and Acidobacteria (18.15%), whereas most endophytes were Alphaproteobacteria (23.17%) as well as Actinobacteria (29.94%). The relative abundance of rhizosphere bacteria was higher than that in endosphere samples. Fungal rhizosphere and endophyte samples had approximately equal abundances of the Sordariomycetes (23%), while the Pezizomycetes were more abundant in the soil (31.95%) than in the roots (5.70%). The phylogenetic relationships of the abundances of microbes in root and soil samples also showed that the most abundant bacterial and fungal reads tended to be dominant in either the soil or root samples but not both. Additionally, Pearson correlation heatmap analysis showed that the diversity and composition of soil bacteria and fungi were closely related to pH, total nitrogen, total phosphorus, and organic matter, of which pH and organic matter were the main drivers. These results clarify the different patterns of microbial communities of the soil-root continuum, in support of the better conservation and utilization of endangered desert plants in Inner Mongolia. IMPORTANCE Microbial assemblages play significant roles in plant survival, health, and ecological services. The symbiosis between soil microorganisms and these plants and their interactions with soil factors are important features of the adaptation of desert plants to an arid and barren environment. Therefore, the profound study of the microbial diversity of rare desert plants can provide important data to support the protection and utilization of rare desert plants. Accordingly, in this study, high-throughput sequencing technology was applied to study the microbial diversity in plant roots and rhizosphere soils. We expect that research on the relationship between soil and root microbial diversity and the environment will improve the survival of endangered plants in this environment. In summary, this study is the first to study the microbial diversity and community structure of Helianthemum songaricum Schrenk and compare the diversity and composition of the root and soil microbiomes.
Collapse
Affiliation(s)
- Daolong Xu
- Inner Mongolia University, School of Life Sciences, Ministry of Education, Key Laboratory of Forage and Endemic Crop Biotechnology, Hohhot, People’s Republic of China
| | - Xiaowen Yu
- Inner Mongolia Autonomous Region Environmental Monitoring Station, Hohhot, People’s Republic of China
| | - Jin Chen
- National Engineering Laboratory of Crop Stress Resistance Breeding, Anhui Agricultural University, Hefei, People’s Republic of China
| | - Haijing Liu
- Inner Mongolia University, School of Life Sciences, Ministry of Education, Key Laboratory of Forage and Endemic Crop Biotechnology, Hohhot, People’s Republic of China
| | - Yaxin Zheng
- Inner Mongolia University, School of Life Sciences, Ministry of Education, Key Laboratory of Forage and Endemic Crop Biotechnology, Hohhot, People’s Republic of China
| | - Hanqing Qu
- Inner Mongolia University, School of Life Sciences, Ministry of Education, Key Laboratory of Forage and Endemic Crop Biotechnology, Hohhot, People’s Republic of China
| | - Yuying Bao
- Inner Mongolia University, School of Life Sciences, Ministry of Education, Key Laboratory of Forage and Endemic Crop Biotechnology, Hohhot, People’s Republic of China
| |
Collapse
|
9
|
Feng X, He S, Sato T, Kondo T, Uema K, Sato K, Kobayashi H. Enrichment of hydrogen-oxidizing bacteria using a hybrid biological-inorganic system. J Biosci Bioeng 2023; 135:250-257. [PMID: 36650080 DOI: 10.1016/j.jbiosc.2022.12.011] [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: 09/29/2022] [Revised: 12/06/2022] [Accepted: 12/23/2022] [Indexed: 01/19/2023]
Abstract
Hybrid biological-inorganic (HBI) systems comprising inorganic water-splitting catalysts and aerobic hydrogen-oxidizing bacteria (HOB) have previously been used for CO2 conversion. In order to identify new biocatalysts for CO2 conversion, the present study used an HBI system to enrich HOB directly from environmental samples. Three sediment samples (from a brackish water pond, a beach, and a tide pool) and two activated sludge samples (from two separate sewage plants) were inoculated into HBI systems using a cobalt phosphorus (Co-P) alloy and cobalt phosphate (CoPi) as inorganic catalysts with a fixed voltage of 2.0 V. The gas composition of the reactor headspaces and electric current were monitored. An aliquot of the reactor medium was transferred to a new reactor when significant consumption of H2 and CO2 was detected. This process was repeated twice (with three reactors in operation for each sample) to enrich HOB. Increased biomass concomitant with increased H2 and CO2 consumption was observed in the third reactor, indicating enrichment of HOB. 16S rRNA gene amplicon sequencing demonstrated enrichment of sequences related to HOB (including bacteria from Mycobacterium, Hydrogenophaga, and Xanthobacter genera) over successive sub-cultures. Finally, four different HOB belonging to the Mycobacterium, Hydrogenophaga, Xanthobacter, and Acidovorax genera were isolated from reactor media, representing potential candidates as HBI system biocatalysts.
Collapse
Affiliation(s)
- Xiang Feng
- Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Sijia He
- Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Taiki Sato
- Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takumi Kondo
- Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Koyo Uema
- Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kozo Sato
- Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan; Frontier Research Center for Energy and Resource (FRCER), Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hajime Kobayashi
- Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan; Frontier Research Center for Energy and Resource (FRCER), Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
| |
Collapse
|
10
|
Huber KJ, Pester M, Eichorst SA, Navarrete AA, Foesel BU. Editorial: Acidobacteria – Towards Unraveling the Secrets of a Widespread, Though Enigmatic, Phylum. Front Microbiol 2022; 13:960602. [PMID: 35814658 PMCID: PMC9267355 DOI: 10.3389/fmicb.2022.960602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Katharina J. Huber
- Department Microorganisms, Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Michael Pester
- Department Microorganisms, Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
- Institute for Microbiology, Technical University of Braunschweig, Braunschweig, Germany
| | - Stephanie A. Eichorst
- Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Acacio A. Navarrete
- Graduate Program in Environmental Sciences, University Brazil, São Paulo, Brazil
| | - Bärbel U. Foesel
- Working Group Biobank, Research Unit Molecular Epidemiology, Institute of Epidemiology, Helmholtz Munich, German Research Center for Environmental Health, Neuherberg, Germany
- *Correspondence: Bärbel U. Foesel
| |
Collapse
|
11
|
Sui J, Yu Q, Yang K, Yang J, Li C, Liu X. Effects of Bacillus subtilis T6-1 on the Rhizosphere Microbial Community Structure of Continuous Cropping Poplar. BIOLOGY 2022; 11:biology11050791. [PMID: 35625519 PMCID: PMC9138279 DOI: 10.3390/biology11050791] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 05/18/2022] [Accepted: 05/18/2022] [Indexed: 11/29/2022]
Abstract
Simple Summary Long-term continuous cropping of poplar has led to a decline in soil fertility, the timber yield of poplar has decreased, and diseases and pests have increased. We aimed to develop a biological agent that regulates the structure of the microbial community of the poplar rhizosphere and alleviates the effects of continuous poplar cropping. The research showed that T6-1 could improve the structure of the microbial community of the poplar rhizosphere and promote the growth of poplars. Thus, it could be used as a biological control agent against continuous cropping obstacles for poplar trees. Abstract The continuous cropping obstacles in poplar cultivation cause declines in wood yield and serious soil-borne diseases, mainly because of structural alterations in the microbial community and the aggregation of pathogenic fungi. Bacillus subtilis T6-1, isolated from poplar rhizospheric soil, has strong antagonistic effects on poplar pathogens. We aimed to investigate the effects of B. subtilis T6-1 on the structure of the microbial community in the poplar rhizosphere. Poplar seedlings were replanted in three successive generations of soil. The diameter at breast height, plant height, and the number of culturable bacteria of the poplars inoculated with T6-1 exceeded those in the non-inoculated control group. qPCR analysis revealed that the total abundance of T6-1 bacteria in the treated poplars was remarkably higher in contrast to that in the control group. Illumina MiSeq sequencing was employed to track the alterations in diversity and structure of the total microbial community in the poplar rhizosphere inoculated with B. subtilis T6-1. Fungal diversity and abundance in the T6-1 rhizosphere were remarkably lower in contrast with those in the control rhizosphere. The proportion of Bacillus sp. in the total bacterial community in the T6-1 and control groups was 3.04% and 2.38%, respectively, while those of the Rhizoctonia sp. was 2.02% and 5.82%, respectively. In conclusion, B. subtilis T6-1 has the potential to serve as a microbial agent, enhancing the structure of the rhizosphere microbial community as well as promoting tree growth in poplar cultivation.
Collapse
Affiliation(s)
- Junkang Sui
- College of Agronomy and Agricultural Engineering, Liaocheng University, Liaocheng 252000, China; (J.Y.); (C.L.)
- Correspondence:
| | - Qianqian Yu
- Department of Architecture and Civil Engineering, Shandong Liaocheng Vocational and Technical College, Liaocheng 252000, China;
| | - Kai Yang
- Liaocheng Food and Drug Inspection and Testing Center, Liaocheng 252000, China;
| | - Jiayi Yang
- College of Agronomy and Agricultural Engineering, Liaocheng University, Liaocheng 252000, China; (J.Y.); (C.L.)
| | - Chenyu Li
- College of Agronomy and Agricultural Engineering, Liaocheng University, Liaocheng 252000, China; (J.Y.); (C.L.)
| | - Xunli Liu
- College of Forestry, Shandong Agricultural University, Tai’an 271000, China;
| |
Collapse
|
12
|
Greening C, Grinter R. Microbial oxidation of atmospheric trace gases. Nat Rev Microbiol 2022; 20:513-528. [PMID: 35414013 DOI: 10.1038/s41579-022-00724-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2022] [Indexed: 02/06/2023]
Abstract
The atmosphere has recently been recognized as a major source of energy sustaining life. Diverse aerobic bacteria oxidize the three most abundant reduced trace gases in the atmosphere, namely hydrogen (H2), carbon monoxide (CO) and methane (CH4). This Review describes the taxonomic distribution, physiological role and biochemical basis of microbial oxidation of these atmospheric trace gases, as well as the ecological, environmental, medical and astrobiological importance of this process. Most soil bacteria and some archaea can survive by using atmospheric H2 and CO as alternative energy sources, as illustrated through genetic studies on Mycobacterium cells and Streptomyces spores. Certain specialist bacteria can also grow on air alone, as confirmed by the landmark characterization of Methylocapsa gorgona, which grows by simultaneously consuming atmospheric CH4, H2 and CO. Bacteria use high-affinity lineages of metalloenzymes, namely hydrogenases, CO dehydrogenases and methane monooxygenases, to utilize atmospheric trace gases for aerobic respiration and carbon fixation. More broadly, trace gas oxidizers enhance the biodiversity and resilience of soil and marine ecosystems, drive primary productivity in extreme environments such as Antarctic desert soils and perform critical regulatory services by mitigating anthropogenic emissions of greenhouse gases and toxic pollutants.
Collapse
Affiliation(s)
- Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia. .,Securing Antarctica's Environmental Future, Monash University, Clayton, Victoria, Australia. .,Centre to Impact AMR, Monash University, Clayton, Victoria, Australia.
| | - Rhys Grinter
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
| |
Collapse
|
13
|
Sikorski J, Baumgartner V, Birkhofer K, Boeddinghaus RS, Bunk B, Fischer M, Fösel BU, Friedrich MW, Göker M, Hölzel N, Huang S, Huber KJ, Kandeler E, Klaus VH, Kleinebecker T, Marhan S, von Mering C, Oelmann Y, Prati D, Regan KM, Richter-Heitmann T, Rodrigues JFM, Schmitt B, Schöning I, Schrumpf M, Schurig E, Solly EF, Wolters V, Overmann J. The Evolution of Ecological Diversity in Acidobacteria. Front Microbiol 2022; 13:715637. [PMID: 35185839 PMCID: PMC8847707 DOI: 10.3389/fmicb.2022.715637] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 01/10/2022] [Indexed: 12/15/2022] Open
Abstract
Acidobacteria occur in a large variety of ecosystems worldwide and are particularly abundant and highly diverse in soils. In spite of their diversity, only few species have been characterized to date which makes Acidobacteria one of the most poorly understood phyla among the domain Bacteria. We used a culture-independent niche modeling approach to elucidate ecological adaptations and their evolution for 4,154 operational taxonomic units (OTUs) of Acidobacteria across 150 different, comprehensively characterized grassland soils in Germany. Using the relative abundances of their 16S rRNA gene transcripts, the responses of active OTUs along gradients of 41 environmental variables were modeled using hierarchical logistic regression (HOF), which allowed to determine values for optimum activity for each variable (niche optima). By linking 16S rRNA transcripts to the phylogeny of full 16S rRNA gene sequences, we could trace the evolution of the different ecological adaptations during the diversification of Acidobacteria. This approach revealed a pronounced ecological diversification even among acidobacterial sister clades. Although the evolution of habitat adaptation was mainly cladogenic, it was disrupted by recurrent events of convergent evolution that resulted in frequent habitat switching within individual clades. Our findings indicate that the high diversity of soil acidobacterial communities is largely sustained by differential habitat adaptation even at the level of closely related species. A comparison of niche optima of individual OTUs with the phenotypic properties of their cultivated representatives showed that our niche modeling approach (1) correctly predicts those physiological properties that have been determined for cultivated species of Acidobacteria but (2) also provides ample information on ecological adaptations that cannot be inferred from standard taxonomic descriptions of bacterial isolates. These novel information on specific adaptations of not-yet-cultivated Acidobacteria can therefore guide future cultivation trials and likely will increase their cultivation success.
Collapse
Affiliation(s)
- Johannes Sikorski
- Department of Microbial Ecology and Diversity Research, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Vanessa Baumgartner
- Department of Microbial Ecology and Diversity Research, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Klaus Birkhofer
- Department of Ecology, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, Germany
| | - Runa S. Boeddinghaus
- Soil Biology Department, Institute of Soil Science and Land Evaluation, University of Hohenheim, Stuttgart, Germany
| | - Boyke Bunk
- Bioinformatics Group, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Markus Fischer
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Bärbel U. Fösel
- Department of Microbial Ecology and Diversity Research, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Michael W. Friedrich
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
| | - Markus Göker
- Bioinformatics Group, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Norbert Hölzel
- Biodiversity and Ecosystem Research Group, Institute of Landscape Ecology, University Münster, Münster, Germany
| | - Sixing Huang
- Bioinformatics Group, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Katharina J. Huber
- Department of Microbial Ecology and Diversity Research, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Ellen Kandeler
- Soil Biology Department, Institute of Soil Science and Land Evaluation, University of Hohenheim, Stuttgart, Germany
| | | | - Till Kleinebecker
- Institute of Landscape Ecology and Resources Management, University of GieBen, GieBen, Germany
| | - Sven Marhan
- Soil Biology Department, Institute of Soil Science and Land Evaluation, University of Hohenheim, Stuttgart, Germany
| | - Christian von Mering
- Institute of Molecular Life Sciences and Swiss Institute of Bioinformatics, University of Zurich, Zurich, Switzerland
| | | | - Daniel Prati
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Kathleen M. Regan
- Soil Biology Department, Institute of Soil Science and Land Evaluation, University of Hohenheim, Stuttgart, Germany
| | - Tim Richter-Heitmann
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
| | - João F. Matias Rodrigues
- Institute of Molecular Life Sciences and Swiss Institute of Bioinformatics, University of Zurich, Zurich, Switzerland
| | - Barbara Schmitt
- Institute of Plant Sciences, University of Bern, Bern, Switzerland
| | - Ingo Schöning
- Department for Biogeochemical Processes and Biogeochemical Integration, Max-Planck Institute for Biogeochemistry, Jena, Germany
| | - Marion Schrumpf
- Department for Biogeochemical Processes and Biogeochemical Integration, Max-Planck Institute for Biogeochemistry, Jena, Germany
| | | | - Emily F. Solly
- Department for Biogeochemical Processes and Biogeochemical Integration, Max-Planck Institute for Biogeochemistry, Jena, Germany
| | | | - Jörg Overmann
- Department of Microbial Ecology and Diversity Research, Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
- Microbiology, Faculty of Life Sciences, Technische Universität Braunschweig, Braunschweig, Germany
| |
Collapse
|
14
|
Negri T, Mantri S, Angelov A, Peter S, Muth G, Eustáquio AS, Ziemert N. A rapid and efficient strategy to identify and recover biosynthetic gene clusters from soil metagenomes. Appl Microbiol Biotechnol 2022; 106:3293-3306. [PMID: 35435454 PMCID: PMC9064862 DOI: 10.1007/s00253-022-11917-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/31/2022] [Accepted: 04/03/2022] [Indexed: 11/30/2022]
Abstract
Culture-independent metagenomic approaches offer a promising solution to the discovery of therapeutically relevant compounds such as antibiotics by enabling access to the hidden biosynthetic potential of microorganisms. These strategies, however, often entail laborious, multi-step, and time-consuming procedures to recover the biosynthetic gene clusters (BGCs) from soil metagenomes for subsequent heterologous expression. Here, we developed an efficient method we called single Nanopore read cluster mining (SNRCM), which enables the fast recovery of complete BGCs from a soil metagenome using long- and short-read sequencing. A metagenomic fosmid library of 83,700 clones was generated and sequenced using Nanopore as well as Illumina technologies. Hybrid assembled contigs of the sequenced fosmid library were subsequently analyzed to identify BGCs encoding secondary metabolites. Using SNRCM, we aligned the identified BGCs directly to Nanopore long-reads and were able to detect complete BGCs on single fosmids. This enabled us to select for and recover BGCs of interest for subsequent heterologous expression attempts. Additionally, the sequencing data of the fosmid library and its corresponding metagenomic DNA enabled us to assemble and recover a large nonribosomal peptide synthetase (NRPS) BGC from three different fosmids of our library and to directly amplify and recover a complete lasso peptide BGC from the high-quality metagenomic DNA. Overall, the strategies presented here provide a useful tool for accelerating and facilitating the identification and production of potentially interesting bioactive compounds from soil metagenomes. KEY POINTS: • An efficient approach for the recovery of BGCs from soil metagenomes was developed to facilitate natural product discovery. • A fosmid library was constructed from soil metagenomic HMW DNA and sequenced via Illumina and Nanopore. • Nanopore long-reads enabled the direct identification and recovery of complete BGCs on single fosmids.
Collapse
Affiliation(s)
- Timo Negri
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Shrikant Mantri
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany ,Interfaculty Institute for Biomedical Informatics (IBMI), University of Tübingen, Tübingen, Germany ,Computational Biology Laboratory, National Agri-Food Biotechnology Institute (NABI), Mohali, Punjab India
| | - Angel Angelov
- NGS Competence Center Tübingen (NCCT), Institut Für Medizinische Mikrobiologie Und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Silke Peter
- NGS Competence Center Tübingen (NCCT), Institut Für Medizinische Mikrobiologie Und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Günther Muth
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | | | - Nadine Ziemert
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany. .,Interfaculty Institute for Biomedical Informatics (IBMI), University of Tübingen, Tübingen, Germany. .,German Centre for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany.
| |
Collapse
|
15
|
Bay SK, Waite DW, Dong X, Gillor O, Chown SL, Hugenholtz P, Greening C. Chemosynthetic and photosynthetic bacteria contribute differentially to primary production across a steep desert aridity gradient. THE ISME JOURNAL 2021; 15:3339-3356. [PMID: 34035443 PMCID: PMC8528921 DOI: 10.1038/s41396-021-01001-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 04/16/2021] [Accepted: 04/28/2021] [Indexed: 02/04/2023]
Abstract
Desert soils harbour diverse communities of aerobic bacteria despite lacking substantial organic carbon inputs from vegetation. A major question is therefore how these communities maintain their biodiversity and biomass in these resource-limiting ecosystems. Here, we investigated desert topsoils and biological soil crusts collected along an aridity gradient traversing four climatic regions (sub-humid, semi-arid, arid, and hyper-arid). Metagenomic analysis indicated these communities vary in their capacity to use sunlight, organic compounds, and inorganic compounds as energy sources. Thermoleophilia, Actinobacteria, and Acidimicrobiia were the most abundant and prevalent bacterial classes across the aridity gradient in both topsoils and biocrusts. Contrary to the classical view that these taxa are obligate organoheterotrophs, genome-resolved analysis suggested they are metabolically flexible, with the capacity to also use atmospheric H2 to support aerobic respiration and often carbon fixation. In contrast, Cyanobacteria were patchily distributed and only abundant in certain biocrusts. Activity measurements profiled how aerobic H2 oxidation, chemosynthetic CO2 fixation, and photosynthesis varied with aridity. Cell-specific rates of atmospheric H2 consumption increased 143-fold along the aridity gradient, correlating with increased abundance of high-affinity hydrogenases. Photosynthetic and chemosynthetic primary production co-occurred throughout the gradient, with photosynthesis dominant in biocrusts and chemosynthesis dominant in arid and hyper-arid soils. Altogether, these findings suggest that the major bacterial lineages inhabiting hot deserts use different strategies for energy and carbon acquisition depending on resource availability. Moreover, they highlight the previously overlooked roles of Actinobacteriota as abundant primary producers and trace gases as critical energy sources supporting productivity and resilience of desert ecosystems.
Collapse
Affiliation(s)
- Sean K Bay
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- School of Biological Sciences, Monash University, Clayton, VIC, Australia.
| | - David W Waite
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD, Australia
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Xiyang Dong
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sde Boker, Israel
| | - Steven L Chown
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Philip Hugenholtz
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD, Australia
| | - Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- School of Biological Sciences, Monash University, Clayton, VIC, Australia.
| |
Collapse
|
16
|
Greening C, Islam ZF, Bay SK. Hydrogen is a major lifeline for aerobic bacteria. Trends Microbiol 2021; 30:330-337. [PMID: 34462186 DOI: 10.1016/j.tim.2021.08.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/06/2021] [Accepted: 08/09/2021] [Indexed: 12/31/2022]
Abstract
Molecular hydrogen (H2) is available in trace amounts in most ecosystems through atmospheric, biological, geochemical, and anthropogenic sources. Aerobic bacteria use this energy-dense gas, including at atmospheric concentrations, to support respiration and carbon fixation. While it was thought that aerobic H2 consumers are rare community members, here we summarize evidence suggesting that they are dominant throughout soils and other aerated ecosystems. Bacterial cultures from at least eight major phyla can consume atmospheric H2. At the ecosystem scale, H2 consumers are abundant, diverse, and active across diverse soils and are key primary producers in extreme environments such as hyper-arid deserts. On this basis, we propose that H2 is a universally available energy source for the survival of aerobic bacteria.
Collapse
Affiliation(s)
- Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Securing Antarctica's Environmental Future, Monash University, Clayton, VIC 3800, Australia; Centre to Impact AMR, Monash University, Clayton, VIC 3800, Australia.
| | - Zahra F Islam
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; STEM College, RMIT University, Bundoora, VIC 3083, Australia
| | - Sean K Bay
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Securing Antarctica's Environmental Future, Monash University, Clayton, VIC 3800, Australia; School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| |
Collapse
|
17
|
Termite gas emissions select for hydrogenotrophic microbial communities in termite mounds. Proc Natl Acad Sci U S A 2021; 118:2102625118. [PMID: 34285074 DOI: 10.1073/pnas.2102625118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Organoheterotrophs are the dominant bacteria in most soils worldwide. While many of these bacteria can subsist on atmospheric hydrogen (H2), levels of this gas are generally insufficient to sustain hydrogenotrophic growth. In contrast, bacteria residing within soil-derived termite mounds are exposed to high fluxes of H2 due to fermentative production within termite guts. Here, we show through community, metagenomic, and biogeochemical profiling that termite emissions select for a community dominated by diverse hydrogenotrophic Actinobacteriota and Dormibacterota. Based on metagenomic short reads and derived genomes, uptake hydrogenase and chemosynthetic RuBisCO genes were significantly enriched in mounds compared to surrounding soils. In situ and ex situ measurements confirmed that high- and low-affinity H2-oxidizing bacteria were highly active in the mounds, such that they efficiently consumed all termite-derived H2 emissions and served as net sinks of atmospheric H2 Concordant findings were observed across the mounds of three different Australian termite species, with termite activity strongly predicting H2 oxidation rates (R 2 = 0.82). Cell-specific power calculations confirmed the potential for hydrogenotrophic growth in the mounds with most termite activity. In contrast, while methane is produced at similar rates to H2 by termites, mounds contained few methanotrophs and were net sources of methane. Altogether, these findings provide further evidence of a highly responsive terrestrial sink for H2 but not methane and suggest H2 availability shapes composition and activity of microbial communities. They also reveal a unique arthropod-bacteria interaction dependent on H2 transfer between host-associated and free-living microbial communities.
Collapse
|
18
|
Meier DV, Imminger S, Gillor O, Woebken D. Distribution of Mixotrophy and Desiccation Survival Mechanisms across Microbial Genomes in an Arid Biological Soil Crust Community. mSystems 2021; 6:e00786-20. [PMID: 33436509 PMCID: PMC7901476 DOI: 10.1128/msystems.00786-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023] Open
Abstract
Desert surface soils devoid of plant cover are populated by a variety of microorganisms, many with yet unresolved physiologies and lifestyles. Nevertheless, a common feature vital for these microorganisms inhabiting arid soils is their ability to survive long drought periods and reactivate rapidly in rare incidents of rain. Chemolithotrophic processes such as oxidation of atmospheric hydrogen and carbon monoxide are suggested to be a widespread energy source to support dormancy and resuscitation in desert soil microorganisms. Here, we assessed the distribution of chemolithotrophic, phototrophic, and desiccation-related metabolic potential among microbial populations in arid biological soil crusts (BSCs) from the Negev Desert, Israel, via population-resolved metagenomic analysis. While the potential to utilize light and atmospheric hydrogen as additional energy sources was widespread, carbon monoxide oxidation was less common than expected. The ability to utilize continuously available energy sources might decrease the dependency of mixotrophic populations on organic storage compounds and carbon provided by the BSC-founding cyanobacteria. Several populations from five different phyla besides the cyanobacteria encoded CO2 fixation potential, indicating further potential independence from photoautotrophs. However, we also found population genomes with a strictly heterotrophic genetic repertoire. The highly abundant Rubrobacteraceae (Actinobacteriota) genomes showed particular specialization for this extreme habitat, different from their closest cultured relatives. Besides the ability to use light and hydrogen as energy sources, they encoded extensive O2 stress protection and unique DNA repair potential. The uncovered differences in metabolic potential between individual, co-occurring microbial populations enable predictions of their ecological niches and generation of hypotheses on the dynamics and interactions among them.IMPORTANCE This study represents a comprehensive community-wide genome-centered metagenome analysis of biological soil crust (BSC) communities in arid environments, providing insights into the distribution of genes encoding different energy generation mechanisms, as well as survival strategies, among populations in an arid soil ecosystem. It reveals the metabolic potential of several uncultured and previously unsequenced microbial genera, families, and orders, as well as differences in the metabolic potential between the most abundant BSC populations and their cultured relatives, highlighting once more the danger of inferring function on the basis of taxonomy. Assigning functional potential to individual populations allows for the generation of hypotheses on trophic interactions and activity patterns in arid soil microbial communities and represents the basis for future resuscitation and activity studies of the system, e.g., involving metatranscriptomics.
Collapse
Affiliation(s)
- Dimitri V Meier
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Stefanie Imminger
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sde Boker, Israel
| | - Dagmar Woebken
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| |
Collapse
|