1
|
Graham EB, Garayburu-Caruso VA, Wu R, Zheng J, McClure R, Jones GD. Genomic fingerprints of the world's soil ecosystems. mSystems 2024; 9:e0111223. [PMID: 38722174 DOI: 10.1128/msystems.01112-23] [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: 10/18/2023] [Accepted: 03/25/2024] [Indexed: 06/19/2024] Open
Abstract
Despite the explosion of soil metagenomic data, we lack a synthesized understanding of patterns in the distribution and functions of soil microorganisms. These patterns are critical to predictions of soil microbiome responses to climate change and resulting feedbacks that regulate greenhouse gas release from soils. To address this gap, we assay 1,512 manually curated soil metagenomes using complementary annotation databases, read-based taxonomy, and machine learning to extract multidimensional genomic fingerprints of global soil microbiomes. Our objective is to uncover novel biogeographical patterns of soil microbiomes across environmental factors and ecological biomes with high molecular resolution. We reveal shifts in the potential for (i) microbial nutrient acquisition across pH gradients; (ii) stress-, transport-, and redox-based processes across changes in soil bulk density; and (iii) greenhouse gas emissions across biomes. We also use an unsupervised approach to reveal a collection of soils with distinct genomic signatures, characterized by coordinated changes in soil organic carbon, nitrogen, and cation exchange capacity and in bulk density and clay content that may ultimately reflect soil environments with high microbial activity. Genomic fingerprints for these soils highlight the importance of resource scavenging, plant-microbe interactions, fungi, and heterotrophic metabolisms. Across all analyses, we observed phylogenetic coherence in soil microbiomes-more closely related microorganisms tended to move congruently in response to soil factors. Collectively, the genomic fingerprints uncovered here present a basis for global patterns in the microbial mechanisms underlying soil biogeochemistry and help beget tractable microbial reaction networks for incorporation into process-based models of soil carbon and nutrient cycling.IMPORTANCEWe address a critical gap in our understanding of soil microorganisms and their functions, which have a profound impact on our environment. We analyzed 1,512 global soils with advanced analytics to create detailed genetic profiles (fingerprints) of soil microbiomes. Our work reveals novel patterns in how microorganisms are distributed across different soil environments. For instance, we discovered shifts in microbial potential to acquire nutrients in relation to soil acidity, as well as changes in stress responses and potential greenhouse gas emissions linked to soil structure. We also identified soils with putative high activity that had unique genomic characteristics surrounding resource acquisition, plant-microbe interactions, and fungal activity. Finally, we observed that closely related microorganisms tend to respond in similar ways to changes in their surroundings. Our work is a significant step toward comprehending the intricate world of soil microorganisms and its role in the global climate.
Collapse
Affiliation(s)
- Emily B Graham
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington, USA
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Vanessa A Garayburu-Caruso
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Ruonan Wu
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Jianqiu Zheng
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Ryan McClure
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Gerrad D Jones
- Department of Biological and Ecological Engineering, Oregon State University, Corvallis, Oregon, USA
| |
Collapse
|
2
|
Jiraska L, Jones B, Knight SJ, Lennox J, Goddard MR. Soil and bark biodiversity forms discrete islands between vineyards that are not affected by distance or management regime. Environ Microbiol 2023; 25:3655-3670. [PMID: 37905675 DOI: 10.1111/1462-2920.16513] [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: 01/30/2023] [Accepted: 09/20/2023] [Indexed: 11/02/2023]
Abstract
Within geographic regions, the existing data suggest that physical habitat (bark, soil, etc.) is the strongest factor determining agroecosystem microbial community assemblage, followed by geographic location (site), and then management regime (organic, conventional, etc.). The data also suggest community similarities decay with increasing geographic distance. However, integrated hypotheses for these observations have not been developed. We formalized and tested such hypotheses by sequencing 3.8 million bacterial 16S, fungal ITS2 and non-fungal eukaryotic COI barcodes deriving from 108 samples across two habitats (soil and bark) from six vineyards sites under conventional or conservation management. We found both habitat and site significantly affected community assemblage, with habitat the stronger for bacteria only, but there was no effect of management. There was no evidence for community similarity distance-decay within sites within each habitat. While communities significantly differed between vineyard sites, there was no evidence for between site community similarity distance-decay apart from bark bacterial communities, and no correlations with soil and bark pH apart from soil bacterial communities. Thus, within habitats, vineyard sites represent discrete biodiversity islands, and while bacterial, fungal and non-fungal eukaryotic biodiversity mostly differs between sites, the distance by which they are separated does not define how different they are.
Collapse
Affiliation(s)
- Lucie Jiraska
- The School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Beatrix Jones
- The School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Sarah J Knight
- The School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Jed Lennox
- The School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Matthew R Goddard
- The School of Biological Sciences, University of Auckland, Auckland, New Zealand
- The School of Life and Environmental Sciences, University of Lincoln, Lincoln, UK
| |
Collapse
|
3
|
Van Cauwenberghe J, Simms EL. How might bacteriophages shape biological invasions? mBio 2023; 14:e0188623. [PMID: 37812005 PMCID: PMC10653932 DOI: 10.1128/mbio.01886-23] [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] [Indexed: 10/10/2023] Open
Abstract
Invasions by eukaryotes dependent on environmentally acquired bacterial mutualists are often limited by the ability of bacterial partners to survive and establish free-living populations. Focusing on the model legume-rhizobium mutualism, we apply invasion biology hypotheses to explain how bacteriophages can impact the competitiveness of introduced bacterial mutualists. Predicting how phage-bacteria interactions affect invading eukaryotic hosts requires knowing the eco-evolutionary constraints of introduced and native microbial communities, as well as their differences in abundance and diversity. By synthesizing research from invasion biology, as well as bacterial, viral, and community ecology, we create a conceptual framework for understanding and predicting how phages can affect biological invasions through their effects on bacterial mutualists.
Collapse
Affiliation(s)
- Jannick Van Cauwenberghe
- Institute of Biodiversity, Faculty of Biological Sciences, Cluster of Excellence Balance of the Microverse, Friedrich Schiller University Jena, Jena, Germany
- Department of Integrative Biology, University of California, Berkeley, California, USA
| | - Ellen L. Simms
- Department of Integrative Biology, University of California, Berkeley, California, USA
| |
Collapse
|
4
|
Wang C, Smith GR, Gao C, Peay KG. Dispersal changes soil bacterial interactions with fungal wood decomposition. ISME COMMUNICATIONS 2023; 3:44. [PMID: 37137953 PMCID: PMC10156657 DOI: 10.1038/s43705-023-00253-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 04/12/2023] [Accepted: 04/20/2023] [Indexed: 05/05/2023]
Abstract
Although microbes are the major agent of wood decomposition - a key component of the carbon cycle - the degree to which microbial community dynamics affect this process is unclear. One key knowledge gap is the extent to which stochastic variation in community assembly, e.g. due to historical contingency, can substantively affect decomposition rates. To close this knowledge gap, we manipulated the pool of microbes dispersing into laboratory microcosms using rainwater sampled across a transition zone between two vegetation types with distinct microbial communities. Because the laboratory microcosms were initially identical this allowed us to isolate the effect of changing microbial dispersal directly on community structure, biogeochemical cycles and wood decomposition. Dispersal significantly affected soil fungal and bacterial community composition and diversity, resulting in distinct patterns of soil nitrogen reduction and wood mass loss. Correlation analysis showed that the relationship among soil fungal and bacterial community, soil nitrogen reduction and wood mass loss were tightly connected. These results give empirical support to the notion that dispersal can structure the soil microbial community and through it ecosystem functions. Future biogeochemical models including the links between soil microbial community and wood decomposition may improve their precision in predicting wood decomposition.
Collapse
Affiliation(s)
- Cong Wang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, 100101, Beijing, China
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems and Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
| | - Gabriel Reuben Smith
- Global Ecosystem Ecology, Department of Environmental Systems Science, Institute of Integrative Biology, ETH Zürich, Zürich, 8092, Switzerland
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Cheng Gao
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, 100101, Beijing, China
| | - Kabir G Peay
- Department of Biology, Stanford University, Stanford, CA, 94305, USA.
- Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA.
| |
Collapse
|
5
|
Zhang W, Wan W, Liu X, Yang Y, Liu M. Stronger Geographic Limitations Shape a Rapid Turnover and Potentially Highly Connected Network of Core Bacteria on Microplastics. MICROBIAL ECOLOGY 2023; 85:1179-1189. [PMID: 35355087 DOI: 10.1007/s00248-022-02000-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 03/17/2022] [Indexed: 05/10/2023]
Abstract
Core microbiota is shared microbial taxa within the same habitat, which is important for understanding the stable and consistent components of the complex microbial assembly. However, information on the microplastic core bacteria from the river ecosystems is poor. Here, we investigated the composition and function of microplastic core bacteria from the Three Gorges Reservoir area along the approximate 662 km of the Yangtze River via full-length 16S rRNA gene sequencing, compared with those in water, sediment, and soil. The results showed that the spatial turnover of bacterial communities in four habitats supported deterministic processes dominated by niche differentiation, which shaped their core bacteria. The composition and function of microplastic core bacteria were significantly different from those in the other three habitats. Rhodobacteraceae was the main component of microplastic core bacteria, while the main component of core bacteria in water, sediment, and soil were Burkholderiaceae (21.90%), Burkholderiaceae (5.01%), Nitrosomonadaceae (4.61%), respectively. Furthermore, microplastic core bacteria had stronger geographic limitations along the Yangtze River in the Three Gorges Reservoir area. Stronger geographic limitations shaped the rapid community turnover and a potentially more connected network for the microplastic core bacteria than water, sediment, and soil. More importantly, microplastic core bacteria had strong potential functions of drug resistance and could cause risks to ecosystems and human health. Microplastic core bacteria were mainly influenced by sediment core bacteria, although the bacteria colonizing on microplastics could be from all the contact environments and original sources. These findings provide important insights into the composition, function, and association of microplastic core bacteria with their surrounding environment.
Collapse
Affiliation(s)
- Weihong Zhang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenjie Wan
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaoning Liu
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China
| | - Yuyi Yang
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China.
- Center of the Plant Ecology, Core Botanical Gardens, Wuhan Botanical Garden Chinese Academy of Sciences, Lumo Road No.1, Wuchang District, Wuhan, 430074, China.
| | - Minxia Liu
- College of Forestry, Shanxi Agricultural University, Taigu County, 030801, China
| |
Collapse
|
6
|
Rimet F, Pinseel E, Bouchez A, Japoshvili B, Mumladze L. Diatom endemism and taxonomic turnover: Assessment in high-altitude alpine lakes covering a large geographical range. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 871:161970. [PMID: 36740061 DOI: 10.1016/j.scitotenv.2023.161970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 01/24/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Diatoms are widely used as ecological indicators and show various degrees of endemism. Many studies that support the idea of endemic species integrate several climate zones, a variety of ecosystem types, and often focus on a global scale. Here, we investigated whether endemism could be detected when considering a homogeneous type of ecosystem in a single climate zone. We sampled stone biofilms at 40-50 cm depth in high-altitude lakes in the Alpine climate zone. A total of 149 samples were obtained from the French and Georgian mountains, two areas separated by ∼3000 km. Using Amplicon Sequence Variants derived from DNA metabarcoding, we assessed taxonomic turnover and Zeta-diversity (a measure of endemism). We ran haplotype networks and phylogenetic tests to measure geographical signal in the phylogenies of dominant taxa. The French and Georgian communities shared 51 % of species. Species that were not shared across both regions were mostly rare, and often not characteristic of lakes but of neighboring habitats instead. In contrast, at the sub-species level, 87 % of the genotypes showed restricted distributions. Whereas endemism was the rule at sub-species level, most species were shared across both French and Georgian lakes, suggesting that geographic barriers strongly limited dispersal at the sub-species level but not species level. Dominant species hosted higher levels of sub-specific diversity than rare species. In contrast to global-scale studies, we did not find any significant geographical structuring in the phylogeny of the investigated species. This could indicate ongoing dispersal at a frequency fast enough to prevent allopatric divergence, yet slow enough to prevent sharing most haplotypes between France and Georgia. These results have implications for biomonitoring: depending on the taxonomic level chosen, robust generic tools (species level) or tools dedicated to a region able to discriminate fine pressures differences (sub-species level) may be developed.
Collapse
Affiliation(s)
- Frédéric Rimet
- UMR Carrtel, INRAE, Université Savoie Mont-Blanc, 75b avenue de Corzent, 74200 Thonon les Bains, France.
| | - Eveline Pinseel
- Department of Biological Sciences, University of Arkansas, 850 W Dickson St, SCEN 601, Fayetteville, AR 72701, USA
| | - Agnès Bouchez
- UMR Carrtel, INRAE, Université Savoie Mont-Blanc, 75b avenue de Corzent, 74200 Thonon les Bains, France
| | - Bella Japoshvili
- Ilia State University, Institute of Zoology, 3/5 Colokashvili ave, 0162 Tbilisi, Georgia
| | - Levan Mumladze
- Ilia State University, Institute of Zoology, 3/5 Colokashvili ave, 0162 Tbilisi, Georgia
| |
Collapse
|
7
|
Deng W, Zhang F, Fornacca D, Yang XY, Xiao W. Those Nematode-Trapping Fungi That are not Everywhere: Hints Towards Soil Microbial Biogeography. J Microbiol 2023:10.1007/s12275-023-00043-7. [PMID: 37022590 DOI: 10.1007/s12275-023-00043-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 04/07/2023]
Abstract
The existence of biogeography for microorganisms is a raising topic in ecology and researchers are employing better distinctions between single species, including the most rare ones, to reveal potential hidden patterns. An important volume of evidence supporting heterogeneous distributions for bacteria, archaea and protists is accumulating, and more recently a few efforts have targeted microscopic fungi. We propose an insight into this latter kingdom by looking at a group of soil nematode-trapping fungi whose species are well-known and easily recognizable. We chose a pure culture approach because of its reliable isolation procedures for this specific group. After morphologically and molecularly identifying all species collected from 2250 samples distributed in 228 locations across Yunnan province of China, we analyzed occurrence frequencies and mapped species, genera, and richness. Results showed an apparent cosmopolitan tendency for this group of fungi, including species richness among sites. However, only four species were widespread across the region, while non-random heterogeneous distributions were observed for the remaining 40 species, both in terms of statistical distribution of species richness reflected by a significant variance-to-mean ratio, as well as in terms of visually discernible spatial clusters of rare species and genera on the map. Moreover, several species were restricted to only one location, raising the question of whether endemicity exists for this microbial group. Finally, environmental heterogeneity showed a marginal contribution in explaining restricted distributions, suggesting that other factors such as geographical isolation and dispersal capabilities should be explored. These findings contribute to our understanding of the cryptic geographic distribution of microorganisms and encourage further research in this direction.
Collapse
Affiliation(s)
- Wei Deng
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, People's Republic of China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, People's Republic of China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, People's Republic of China
| | - Fa Zhang
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, People's Republic of China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, People's Republic of China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, People's Republic of China
| | - Davide Fornacca
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, People's Republic of China.
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, People's Republic of China.
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, People's Republic of China.
- The Key Laboratory of Yunnan Education Department on Er'hai Catchment Conservation and Sustainable Development, Dali, 671003, Yunnan, People's Republic of China.
| | - Xiao-Yan Yang
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, People's Republic of China.
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, People's Republic of China.
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, People's Republic of China.
- The Key Laboratory of Yunnan Education Department on Er'hai Catchment Conservation and Sustainable Development, Dali, 671003, Yunnan, People's Republic of China.
| | - Wen Xiao
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, 671003, Yunnan, People's Republic of China
- Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, 671003, Yunnan, People's Republic of China
- The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, 671003, Yunnan, People's Republic of China
- The Key Laboratory of Yunnan Education Department on Er'hai Catchment Conservation and Sustainable Development, Dali, 671003, Yunnan, People's Republic of China
- Yunling Black-and-White Snub-Nosed Monkey Observation and Research Station of Yunnan Province, Dali, 671003, Yunnan, People's Republic of China
| |
Collapse
|
8
|
Gruet C, Abrouk D, Börner A, Muller D, Moënne-Loccoz Y. Wheat genome architecture influences interactions with phytobeneficial microbial functional groups in the rhizosphere. PLANT, CELL & ENVIRONMENT 2023; 46:1018-1032. [PMID: 36494920 DOI: 10.1111/pce.14508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 11/29/2022] [Accepted: 12/04/2022] [Indexed: 06/17/2023]
Abstract
Wheat has undergone a complex evolutionary history, which led to allopolyploidization and the hexaploid bread wheat Triticum aestivum. However, the significance of wheat genomic architecture for beneficial plant-microbe interactions is poorly understood, especially from a functional standpoint. In this study, we tested the hypothesis that wheat genomic architecture was an overriding factor determining root recruitment of microorganisms with particular plant-beneficial traits. We chose five wheat species representing genomic profiles AA (Triticum urartu), BB {SS} (Aegilops speltoides), DD (Aegilops tauschii), AABB (Triticum dicoccon) and AABBDD (Triticum aestivum) and assessed by quantitative polymerase chain reaction their ability to interact with free-nitrogen fixers, 1-aminocyclopropane-1-carboxylate deaminase producers, 2,4-diacetylphloroglucinol producers and auxin producers via the phenylpyruvate decarboxylase pathway, in combination with Illumina MiSeq metabarcoding analysis of N fixers (and of the total bacterial community). We found that the abundance of the microbial functional groups could fluctuate according to wheat genomic profile, as did the total bacterial abundance. N fixer diversity and total bacterial diversity were also influenced significantly by wheat genomic profile. Often, rather similar results were obtained for genomes DD (Ae. tauschii) and AABBDD (T. aestivum), pointing for the first time that the D genome could be particularly important for wheat-bacteria interactions.
Collapse
Affiliation(s)
- Cécile Gruet
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR5557 Ecologie Microbienne, Villeurbanne, France
| | - Danis Abrouk
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR5557 Ecologie Microbienne, Villeurbanne, France
| | - Andreas Börner
- Genebank Department, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Daniel Muller
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR5557 Ecologie Microbienne, Villeurbanne, France
| | - Yvan Moënne-Loccoz
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR5557 Ecologie Microbienne, Villeurbanne, France
| |
Collapse
|
9
|
Deng W, Yu GB, Yang XY, Xiao W. Testing the passive sampling hypothesis: The role of dispersal in shaping microbial species-area relationship. Front Microbiol 2023; 14:1093695. [PMID: 36778859 PMCID: PMC9909023 DOI: 10.3389/fmicb.2023.1093695] [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: 11/09/2022] [Accepted: 01/06/2023] [Indexed: 01/27/2023] Open
Abstract
Dispersal is one of the key processes determining biodiversity. The passive sampling hypothesis, which emphasizes dispersal processes, suggests that larger habitats receive more species from the species pool as the main mechanism leading to more species in larger habitats than in smaller habitats (i.e., species-area relationships). However, the specific mechanisms by which dispersion shapes biodiversity still need to be discovered due to the difficulties of quantifying dispersal and the influence of multiple factors. Solving the above problem with a designed experiment is necessary to test the passive sampling hypothesis. This study designed a passive sampling experiment using sterile filter paper to quantify the microbial diffusion process, excluding the effects of pure sampling effects, habitat heterogeneity, and extinction processes. The results of high-throughput sequencing showed that a larger filter paper could receive more colonists, and the passive sampling hypothesis of SAR was confirmed. Dispersal shaped SAR by increasing species richness, especially rare species, and increasing the species replacement rate between habitats. These two processes are the mechanisms by which dispersal shapes biodiversity patterns. Compared with the results of this study, the commonly used mathematical model of passive sampling was able to predict the richness of non-rare species accurately but underestimated the richness of rare species. Underestimating rare species by mathematical models of passive sampling is more severe in small habitats. These findings provide new insights into the study of dispersal processes and the mechanism of species-area relationships.
Collapse
Affiliation(s)
- Wei Deng
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, China,Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, Yunnan, China,The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, Yunnan, China
| | - Guo-Bin Yu
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, China,Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, Yunnan, China,The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, Yunnan, China
| | - Xiao-Yan Yang
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, China,Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, Yunnan, China,The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, Yunnan, China,*Correspondence: Xiao-Yan Yang, ✉
| | - Wen Xiao
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, China,Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, Yunnan, China,The Provincial Innovation Team of Biodiversity Conservation and Utility of the Three Parallel Rivers Region, Dali University, Dali, Yunnan, China,International Centre of Biodiversity and Primates Conservation, Dali, Yunnan, China,Yunling Black and White Snub-Nosed Monkey Observation and Research Station of Yunnan Province, Dali, Yunnan, China,Wen Xiao, ✉
| |
Collapse
|
10
|
Kokate PP, Bales E, Joyner D, Hazen TC, Techtmann SM. Biogeographic patterns in populations of marine Pseudoalteromonas atlantica isolates. FEMS Microbiol Lett 2023; 370:fnad081. [PMID: 37573136 DOI: 10.1093/femsle/fnad081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 07/14/2023] [Accepted: 08/11/2023] [Indexed: 08/14/2023] Open
Abstract
Intra-specific genomic diversity is well documented in microbes. The question, however, remains whether natural selection or neutral evolution is the major contributor to this diversity. We undertook this study to estimate genomic diversity in Pseudoalteromonas atlantica populations and whether the diversity, if present, could be attributed to environmental factors or distance effects. We isolated and sequenced twenty-three strains of P. atlantica from three geographically distant deep marine basins and performed comparative genomic analyses to study the genomic diversity of populations among these basins. Average nucleotide identity followed a strictly geographical pattern. In two out of three locations, the strains within the location exhibited >99.5% identity, whereas, among locations, the strains showed <98.11% identity. Phylogenetic and pan-genome analysis also reflected the biogeographical separation of the strains. Strains from the same location shared many accessory genes and clustered closely on the phylogenetic tree. Phenotypic diversity between populations was studied in ten out of twenty-three strains testing carbon and nitrogen source utilization and osmotolerance. A genetic basis for phenotypic diversity could be established in most cases but was apparently not influenced by local environmental conditions. Our study suggests that neutral evolution may have a substantial role in the biodiversity of P. atlantica.
Collapse
Affiliation(s)
- Prajakta P Kokate
- Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, United States
| | - Erika Bales
- Department of Microbiology, University of Tennessee Knoxville, Knoxville, TN 37996, United States
| | - Dominique Joyner
- Department of Civil and Environmental Engineering, University of Tennessee Knoxville, Knoxville, TN 37996, United States
| | - Terry C Hazen
- Department of Microbiology, University of Tennessee Knoxville, Knoxville, TN 37996, United States
- Department of Civil and Environmental Engineering, University of Tennessee Knoxville, Knoxville, TN 37996, United States
| | - Stephen M Techtmann
- Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, United States
| |
Collapse
|
11
|
Chown SL. Macrophysiology for decision‐making. J Zool (1987) 2022. [DOI: 10.1111/jzo.13029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- S. L. Chown
- Securing Antarctica's Environmental Future, School of Biological Sciences Monash University Melbourne Victoria Australia
| |
Collapse
|
12
|
Baubin C, Ran N, Siebner H, Gillor O. Divergence of Biocrust Active Bacterial Communities in the Negev Desert During a Hydration-Desiccation Cycle. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02063-z. [PMID: 35788422 DOI: 10.1007/s00248-022-02063-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 06/23/2022] [Indexed: 06/15/2023]
Abstract
Rain events in arid environments are highly unpredictable and intersperse extended periods of drought. Therefore, tracking changes in desert soil bacterial communities during rain events, in the field, was seldom attempted. Here, we assessed rain-mediated dynamics of active bacterial communities in the Negev Desert biological soil crust (biocrust). Biocrust samples were collected during, and after a medium rainfall and dry soil was used as a control; we evaluated the changes in active bacterial composition, potential function, potential photosynthetic activity, and extracellular polysaccharide (EPS) production. We hypothesized that rain would activate the biocrust phototrophs (mainly Cyanobacteria), while desiccation would inhibit their activity. In contrast, the biocrust Actinobacteria would decline during rewetting and revive with desiccation. Our results showed that hydration increased chlorophyll content and EPS production. As expected, biocrust rewetting activated Cyanobacteria, which replaced the former dominant Actinobacteria, boosting potential autotrophic functions. However, desiccation of the biocrust did not immediately change the bacterial composition or potential function and was followed by a delayed decrease in chlorophyll and EPS levels. This dramatic shift in the community upon rewetting led to modifications in ecosystem services. We propose that following a rain event, the response of the active bacterial community lagged behind the biocrust water content due to the production of EPS which delayed desiccation and temporarily sustained the biocrust community activity.
Collapse
Affiliation(s)
- Capucine Baubin
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel.
| | - Noya Ran
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Hagar Siebner
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel.
| |
Collapse
|
13
|
Wang Y, Tian S, Wu N, Liu W, Li L, Wang X. Differential Microbial Communities in Paddy Soils Between Guiyang Plateaus and Chengdu Basins Drive the Incidence of Rice Bacterial Diseases. PLANT DISEASE 2022; 106:1882-1889. [PMID: 35021874 DOI: 10.1094/pdis-09-21-1974-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Southwest China has the most complex rice-growing regions in China. With great differences in topography, consisting mainly of basins and plateaus, ecological factors differ greatly between regions. In this study, bulk paddy soils collected from long-term rice fields in Chengdu (basins) and Guiyang (plateaus) were used to study the correlation between microbial diversity and the incidence of rice bacterial diseases. Results showed that the microbial community composition in paddy soils and the microbial functional categories differed significantly between basins and plateaus. They shared >70% of the dominant genera (abundance >1%), but the abundance of the dominant genera differed significantly. Functional analysis found that bulk paddy soils from Chengdu were significantly enriched in virulence factor-related genes; soils from Guiyang were enriched in biosynthesis of secondary metabolites, especially antibiotics. Correspondingly, Chengdu was significantly enriched in leaf bacterial pathogens Acidovorax, Xanthomonas, and Pseudomonas. Greenhouse experiments and correlation analysis showed that soil chemical properties had a greater effect on microbial community composition and positively correlated with the higher incidence of rice bacterial foot rot in Guiyang, whereas temperature had a greater effect on soil microbial functions and positively correlated with the higher severity index of leaf bacterial diseases in Chengdu. Our results provide a new perspective on how differences in microbial communities in paddy soils can influence the incidence of rice bacterial diseases in areas with different topographies.
Collapse
Affiliation(s)
- Yajiao Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Institute of Plant Protection, Hebei Academy of Agricultural and Forestry Sciences, Baoding 071000, China
| | - Shuping Tian
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Nan Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Wenwen Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Li Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Xifeng Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| |
Collapse
|
14
|
Pascoal F, Costa R, Assmy P, Duarte P, Magalhães C. Exploration of the Types of Rarity in the Arctic Ocean from the Perspective of Multiple Methodologies. MICROBIAL ECOLOGY 2022; 84:59-72. [PMID: 34405249 DOI: 10.1007/s00248-021-01821-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
The Arctic Ocean is facing rapid environmental changes with cascading effects on the entire Arctic marine ecosystem. However, we have a limited understanding of the consequences such changes have on bacteria and archaea (prokaryotes) at the base of the marine food web. In this study, we show how the prokaryotic rare biosphere behaves over a range of highly heterogeneous environmental conditions using 16S rRNA gene reads from amplicon and metagenome sequencing data from seawater samples collected during the Norwegian young sea ICE expedition between late winter and early summer. The prokaryotic rare biosphere was analyzed using different approaches: amplicon sequence variants and operational taxonomic units from the 16S rRNA gene amplicons and operational taxonomic units from the 16S rRNA genes of the metagenomes. We found that prokaryotic rare biosphere communities are specific to certain water masses, and that the majority of the rare taxa identified were always rare and disappeared in at least one sample under changing conditions, suggesting their high sensitivity to environmental heterogeneity. In addition, our methodological comparison revealed a good performance of 16S rRNA gene amplicon sequencing in describing rare biosphere patterns, while the metagenome-derived data were better to capture a significant diversity of so-far uncultivated rare taxa. Our analysis on the dynamics of the rare prokaryotic biosphere, by combining different methodological approaches, improves the description of the types of rarity predicted from Community Assembly theory in the Arctic Ocean.
Collapse
Affiliation(s)
- Francisco Pascoal
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Porto, Portugal.
- Faculty of Sciences, University of Porto, Porto, Portugal.
| | - Rodrigo Costa
- Department of Bioengineering, Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico, University of Lisbon, Lisbon, Portugal
- Centre of Marine Sciences (CCMAR), University of Algarve, Faro, Portugal
- U.S. Department of Energy Joint Genome Institute, Berkeley, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Philipp Assmy
- Norwegian Polar Institute, Fram Centre, N-9296, Tromsø, Norway
| | - Pedro Duarte
- Norwegian Polar Institute, Fram Centre, N-9296, Tromsø, Norway
| | - Catarina Magalhães
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Porto, Portugal
- Faculty of Sciences, University of Porto, Porto, Portugal
- School of Science & Engineering, University of Waikato, Hamilton, New Zealand
- Ocean Frontier Institute, Dalhousie University, Halifax, NS, Canada
| |
Collapse
|
15
|
Davison J, Vasar M, Sepp SK, Oja J, Al-Quraishy S, Bueno CG, Cantero JJ, Chimbioputo Fabiano E, Decocq G, Fraser L, Hiiesalu I, Hozzein WN, Koorem K, Moora M, Mucina L, Onipchenko V, Öpik M, Pärtel M, Phosri C, Semchenko M, Vahter T, Tedersoo L, Zobel M. Dominance, diversity, and niche breadth in arbuscular mycorrhizal fungal communities. Ecology 2022; 103:e3761. [PMID: 35582944 DOI: 10.1002/ecy.3761] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 11/08/2022]
Abstract
Classical theory identifies resource competition as the major structuring force of biotic communities and predicts that: (i) levels of dominance and richness in communities are inversely related, (ii) narrow niches allow dense 'packing' in niche space and thus promote diversity, and (iii) dominants are generalists with wide niches, such that locally abundant taxa also exhibit wide distributions. Current empirical support, however, is mixed. We tested these expectations using published data on arbuscular mycorrhizal (AM) fungal community composition worldwide. We recorded the expected negative relationship between dominance and richness and, to a degree, the positive association between local and global dominance. However, contrary to expectation, dominance was pronounced in communities where more specialists were present; and, conversely, richness was higher in communites with more generalists. Thus, resource competition and niche packing appear of limited importance in AM fungal community assembly; rather patterns of dominance and diversity seem more consistent with habitat filtering and stochastic processes. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- John Davison
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Martti Vasar
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Siim-Kaarel Sepp
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Jane Oja
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Saleh Al-Quraishy
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - C Guillermo Bueno
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Juan José Cantero
- Universidad Nacional de Córdoba, Instituto Multidisciplinario de Biología Vegetal, CONICET, Córdoba, Argentina.,Universidad Nacional de Río Cuarto, Departamento de Biología Agrícola, Facultad de Agronomía y Veterinaria, Córdoba, Argentina
| | | | - Guillaume Decocq
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR CNRS 7058), Jules Verne University of Picardie, Amiens, France
| | - Lauchlan Fraser
- Department of Natural Resource Sciences, Thompson Rivers University, Kamloops, British Columbia, Canada
| | - Inga Hiiesalu
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Wael N Hozzein
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia.,Botany and Microbiology Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt
| | - Kadri Koorem
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Mari Moora
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Ladislav Mucina
- Iluka Chair in Vegetation Science and Biogeography, Harry Butler Institute, Murdoch University, Murdoch, Perth, Australia.,Department of Geography & Environmental Studies, Stellenbosch University, Stellenbosch, South Africa
| | - Vladimir Onipchenko
- Department of Ecology and Plant Geography, Faculty of Biology, Moscow Lomonosov State University, Moscow, Russia
| | - Maarja Öpik
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Meelis Pärtel
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Cherdchai Phosri
- Department of Biology, Nakhon Phanom University, Nakhon Phanom, Thailand
| | - Marina Semchenko
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia.,School of Earth and Environmental Sciences, University of Manchester, Manchester, UK
| | - Tanel Vahter
- Institute of Ecology and Earth Sciences, University of Tartu, Estonia
| | - Leho Tedersoo
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia.,Mycology and Microbiology Center, University of Tartu, Tartu, Estonia
| | - Martin Zobel
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia.,Department of Botany, University of Tartu, Tartu, Estonia
| |
Collapse
|
16
|
Thomson T, Fusi M, Bennett-Smith MF, Prinz N, Aylagas E, Carvalho S, Lovelock CE, Jones BH, Ellis JI. Contrasting Effects of Local Environmental and Biogeographic Factors on the Composition and Structure of Bacterial Communities in Arid Monospecific Mangrove Soils. Microbiol Spectr 2022; 10:e0090321. [PMID: 34985338 PMCID: PMC8729789 DOI: 10.1128/spectrum.00903-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 12/11/2021] [Indexed: 12/23/2022] Open
Abstract
Mangrove forests are important biotic sinks of atmospheric CO2 and play an integral role in nutrient-cycling and decontamination of coastal waters, thereby mitigating climatic and anthropogenic stressors. These services are primarily regulated by the activity of the soil microbiome. To understand how environmental changes may affect this vital part of the ecosystem, it is key to understand the patterns that drive microbial community assembly in mangrove forest soils. High-throughput amplicon sequencing (16S rRNA) was applied on samples from arid Avicennia marina forests across different spatial scales from local to regional. Alongside conventional analyses of community ecology, microbial co-occurrence networks were assessed to investigate differences in composition and structure of the bacterial community. The bacterial community composition varied more strongly along an intertidal gradient within each mangrove forest, than between forests in different geographic regions (Australia/Saudi Arabia). In contrast, co-occurrence networks differed primarily between geographic regions, illustrating that the structure of the bacterial community is not necessarily linked to its composition. The local diversity in mangrove forest soils may have important implications for the quantification of biogeochemical processes and is important to consider when planning restoration activities. IMPORTANCE Mangrove ecosystems are increasingly being recognized for their potential to sequester atmospheric carbon, thereby mitigating the effects of anthropogenically driven greenhouse gas emissions. The bacterial community in the soils plays an important role in the breakdown and recycling of carbon and other nutrients. To assess and predict changes in carbon storage, it is important to understand how the bacterial community is shaped by its environment. Here, we compared the bacterial communities of mangrove forests on different spatial scales, from local within-forest to biogeographic comparisons. The bacterial community composition differed more between distinct intertidal zones of the same forest than between forests in distant geographic regions. The calculated network structure of theoretically interacting bacteria, however, differed most between the geographic regions. Our findings highlight the importance of local environmental factors in shaping the microbial soil community in mangroves and highlight a disconnect between community composition and structure in microbial soil assemblages.
Collapse
Affiliation(s)
- T. Thomson
- University of Waikato, School of Science, Tauranga, New Zealand
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, Saudi Arabia
| | - M. Fusi
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, Saudi Arabia
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, United Kingdom
| | - M. F. Bennett-Smith
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, Saudi Arabia
| | - N. Prinz
- University of Waikato, School of Science, Tauranga, New Zealand
| | - E. Aylagas
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, Saudi Arabia
| | - S. Carvalho
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, Saudi Arabia
| | - C. E. Lovelock
- School of Biological Sciences, The University of Queensland, St Lucida, Australia
| | - B. H. Jones
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, Saudi Arabia
| | - J. I. Ellis
- University of Waikato, School of Science, Tauranga, New Zealand
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, Saudi Arabia
| |
Collapse
|
17
|
Assembly of 97 Novel Bacterial Genomes in the Microbial Community Affiliated with Polyvinyl Alcohol in Soil of Northern China. BIOMED RESEARCH INTERNATIONAL 2022; 2022:2229147. [PMID: 35087906 PMCID: PMC8789413 DOI: 10.1155/2022/2229147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 10/05/2021] [Accepted: 10/07/2021] [Indexed: 11/25/2022]
Abstract
Background Undeveloped ecosystems belong to rich source of microbial population, of which resources remain unearthed. A kind of polymeric compound system with high polyvinyl alcohol (PVA) content has been reported and named Taisui. Marker gene amplification showed that Taisui harbored little-explored microbial communities. Aim To address this issue, our study attempted to recover draft genomes and functional potential from microbial communities in Taisui using the metagenomic approach. Material and Methods. Taisui communities provided 97 novel bacterial genomes from 13 bacterial phyla, including bacteria candidate phylum. Two novel genus-level lineages were recovered from Planctomycetes and Chloroflexi. Based on the draft genomes, we expanded the number of taxa with potential productions of PKS and NRPS in phyla including Candidatus Dadabacteria, Chloroflexi, and Planctomycetes. Results A rich diversity of PVA dehydrogenase genes from 4 phyla, involving Proteobacteria, Acidobacteria, Acitinobacteria, and Planctomycetes, were identified. The phylogenetic tree of PVA dehydrogenase showed the possibility of horizontal gene transfer between microbes. Conclusion Our study underscores the substantial microbial diversity and PVA degradation potential in the previously unexplored Taisui system.
Collapse
|
18
|
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
|
19
|
Chen YJ, Leung PM, Wood JL, Bay SK, Hugenholtz P, Kessler AJ, Shelley G, Waite DW, Franks AE, Cook PLM, Greening C. Metabolic flexibility allows bacterial habitat generalists to become dominant in a frequently disturbed ecosystem. THE ISME JOURNAL 2021; 15:2986-3004. [PMID: 33941890 PMCID: PMC8443593 DOI: 10.1038/s41396-021-00988-w] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/25/2021] [Accepted: 04/09/2021] [Indexed: 02/03/2023]
Abstract
Ecological theory suggests that habitat disturbance differentially influences distributions of habitat generalist and specialist species. While well-established for macroorganisms, this theory has rarely been explored for microorganisms. Here we tested these principles in permeable (sandy) sediments, ecosystems with much spatiotemporal variation in resource availability and physicochemical conditions. Microbial community composition and function were profiled in intertidal and subtidal sediments using 16S rRNA gene amplicon sequencing and metagenomics, yielding 135 metagenome-assembled genomes. Community composition and metabolic traits modestly varied with sediment depth and sampling date. Several taxa were highly abundant and prevalent in all samples, including within the orders Woeseiales and Flavobacteriales, and classified as habitat generalists; genome reconstructions indicate these taxa are highly metabolically flexible facultative anaerobes and adapt to resource variability by using different electron donors and acceptors. In contrast, obligately anaerobic taxa such as sulfate reducers and candidate lineage MBNT15 were less abundant overall and only thrived in more stable deeper sediments. We substantiated these findings by measuring three metabolic processes in these sediments; whereas the habitat generalist-associated processes of sulfide oxidation and fermentation occurred rapidly at all depths, the specialist-associated process of sulfate reduction was restricted to deeper sediments. A manipulative experiment also confirmed habitat generalists outcompete specialist taxa during simulated habitat disturbance. Together, these findings show metabolically flexible habitat generalists become dominant in highly dynamic environments, whereas metabolically constrained specialists are restricted to narrower niches. Thus, an ecological theory describing distribution patterns for macroorganisms likely extends to microorganisms. Such findings have broad ecological and biogeochemical ramifications.
Collapse
Affiliation(s)
- Ya-Jou Chen
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Natural Resources Sciences, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Pok Man Leung
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Jennifer L Wood
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, Australia
| | - Sean K Bay
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Philip Hugenholtz
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
| | - Adam J Kessler
- Water Studies Centre, School of Chemistry, Monash University, Clayton, VIC, Australia
- School of Earth, Atmosphere and Environment, Monash University, Clayton, VIC, Australia
| | - Guy Shelley
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - David W Waite
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Ashley E Franks
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, Australia
| | - Perran L M Cook
- Water Studies Centre, School of Chemistry, Monash University, Clayton, VIC, Australia.
| | - Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia.
- School of Biological Sciences, Monash University, Clayton, VIC, Australia.
| |
Collapse
|
20
|
Schwob G, Segovia NI, González-Wevar C, Cabrol L, Orlando J, Poulin E. Exploring the Microdiversity Within Marine Bacterial Taxa: Toward an Integrated Biogeography in the Southern Ocean. Front Microbiol 2021; 12:703792. [PMID: 34335536 PMCID: PMC8317501 DOI: 10.3389/fmicb.2021.703792] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/23/2021] [Indexed: 11/13/2022] Open
Abstract
Most of the microbial biogeographic patterns in the oceans have been depicted at the whole community level, leaving out finer taxonomic resolution (i.e., microdiversity) that is crucial to conduct intra-population phylogeographic study, as commonly done for macroorganisms. Here, we present a new approach to unravel the bacterial phylogeographic patterns combining community-wide survey by 16S rRNA gene metabarcoding and intra-species resolution through the oligotyping method, allowing robust estimations of genetic and phylogeographic indices, and migration parameters. As a proof-of-concept, we focused on the bacterial genus Spirochaeta across three distant biogeographic provinces of the Southern Ocean; maritime Antarctica, sub-Antarctic Islands, and Patagonia. Each targeted Spirochaeta operational taxonomic units were characterized by a substantial intrapopulation microdiversity, and significant genetic differentiation and phylogeographic structure among the three provinces. Gene flow estimations among Spirochaeta populations support the role of the Antarctic Polar Front as a biogeographic barrier to bacterial dispersal between Antarctic and sub-Antarctic provinces. Conversely, the Antarctic Circumpolar Current appears as the main driver of gene flow, connecting sub-Antarctic Islands with Patagonia and maritime Antarctica. Additionally, historical processes (drift and dispersal limitation) govern up to 86% of the spatial turnover among Spirochaeta populations. Overall, our approach bridges the gap between microbial and macrobial ecology by revealing strong congruency with macroorganisms distribution patterns at the populational level, shaped by the same oceanographic structures and ecological processes.
Collapse
Affiliation(s)
- Guillaume Schwob
- Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- Instituto de Ecología y Biodiversidad, Santiago, Chile
| | - Nicolás I. Segovia
- Instituto de Ecología y Biodiversidad, Santiago, Chile
- Universidad Católica del Norte, Coquimbo, Chile
| | - Claudio González-Wevar
- Instituto de Ecología y Biodiversidad, Santiago, Chile
- Facultad de Ciencias, Centro Fondap IDEAL, Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - Léa Cabrol
- Instituto de Ecología y Biodiversidad, Santiago, Chile
- Aix Marseille University, Univ Toulon, CNRS, IRD, Mediterranean Institute of Oceanography (MIO), Marseille, France
| | - Julieta Orlando
- Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Elie Poulin
- Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- Instituto de Ecología y Biodiversidad, Santiago, Chile
| |
Collapse
|
21
|
Zhang Y, Yao P, Sun C, Li S, Shi X, Zhang XH, Liu J. Vertical diversity and association pattern of total, abundant and rare microbial communities in deep-sea sediments. Mol Ecol 2021; 30:2800-2816. [PMID: 33960545 PMCID: PMC8251536 DOI: 10.1111/mec.15937] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 04/21/2021] [Accepted: 04/22/2021] [Indexed: 12/16/2022]
Abstract
Microbial abundance and community composition in marine sediments have been widely explored. However, high‐resolution vertical changes of benthic microbial diversity and co‐occurrence patterns are poorly described. The ecological contributions of abundant and rare species in sediments also remain largely unknown. Here, by analysing microbial populations at 14 depth layers of 10 subseafloor sediment cores (water depth 1,250–3,530 m) obtained in the South China Sea, we provided the vertical profiles of microbial β‐diversity and co‐occurrence influenced by subcommunities of different abundance. These 134 sediment samples were clustered into four groups according to sediment depth (1–2, 6–10, 30–90 and 190–790 cm) with obvious shifts in microbial community compositions. The vertical succession of microorganisms was consistent with redox zonation and influenced by terrestrial inputs. Partitioning of vertical β‐diversity showed extremely high species replacement between deep layers and the surface layer, indicating selection‐induced loss of rare species and dispersal of dormant cells and spores. By contrast, for horizontal β‐diversity, richness of rare species became increasingly significant in deep sediments. Accompanying this β‐diversity profile were clear changes in the association pattern, with microorganisms being less connected in deeper sediment layers, probably reflecting reduced syntrophic interactions. Rare species accounted for an indispensable proportion in the co‐occurrence network, and tended to form complex “small worlds.” The rare subcommunity also responded differently to various environmental factors compared with the abundant subcommunity. Our findings expand current knowledge on vertical changes of marine benthic microbial diversity and their association patterns, emphasizing the potential roles of rare species.
Collapse
Affiliation(s)
- Yunhui Zhang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Peng Yao
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, China
| | - Chuang Sun
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
| | - Sanzhong Li
- Key Laboratory of Submarine Geosciences and Prospecting Techniques, Ministry of Education/College of Marine Geosciences, Ocean University of China, Qingdao, China.,Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Xiaochong Shi
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Xiao-Hua Zhang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Jiwen Liu
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, China
| |
Collapse
|
22
|
Pascoal F, Costa R, Magalhães C. The microbial rare biosphere: current concepts, methods and ecological principles. FEMS Microbiol Ecol 2021; 97:5974270. [PMID: 33175111 DOI: 10.1093/femsec/fiaa227] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 11/06/2020] [Indexed: 01/04/2023] Open
Abstract
Our ability to describe the highly diverse pool of low abundance populations present in natural microbial communities is increasing at an unprecedented pace. Yet we currently lack an integrative view of the key taxa, functions and metabolic activity which make-up this communal pool, usually referred to as the 'rare biosphere', across the domains of life. In this context, this review examines the microbial rare biosphere in its broader sense, providing an historical perspective on representative studies which enabled to bridge the concept from macroecology to microbial ecology. It then addresses our current knowledge of the prokaryotic rare biosphere, and covers emerging insights into the ecology, taxonomy and evolution of low abundance microeukaryotic, viral and host-associated communities. We also review recent methodological advances and provide a synthetic overview on how the rare biosphere fits into different conceptual models used to explain microbial community assembly mechanisms, composition and function.
Collapse
Affiliation(s)
- Francisco Pascoal
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixoes, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal
| | - Rodrigo Costa
- Department of Bioengineering, Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais 1049-001, Lisbon, Portugal.,Centre of Marine Sciences (CCMAR), University of Algarve, Campus de Gambelas, 8005-139, Faro, Portugal.,U.S. Department of Energy Joint Genome Institute, 1 Cyclotron Road, CA 94720, USA.,Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, CA 94720 Berkeley, USA
| | - Catarina Magalhães
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixoes, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal.,Faculty of Sciences, University of Porto, Rua do Campo Alegre s/n, 4169-007, Porto, Portugal.,School of Science, University of Waikato, Gate 1, Knighton Road 3240, Hamilton, New Zealand.,Ocean Frontier Institute, Dalhousie University, Steele Ocean Sciences Building, Dalhousie University 1355 Oxford St., B3H4R2 Halifax, NS, Canada
| |
Collapse
|
23
|
Yan ZZ, Chen QL, Li CY, Thi Nguyen BA, Zhu YG, He JZ, Hu HW. Biotic and abiotic factors distinctly drive contrasting biogeographic patterns between phyllosphere and soil resistomes in natural ecosystems. ISME COMMUNICATIONS 2021; 1:13. [PMID: 36721011 PMCID: PMC9645249 DOI: 10.1038/s43705-021-00012-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 03/02/2021] [Accepted: 03/11/2021] [Indexed: 02/03/2023]
Abstract
The phyllosphere and soil are two of the most important reservoirs of antibiotic resistance genes (ARGs) in terrestrial ecosystems. However, comparative studies on the biogeographic patterns of ARGs in these two habitats are lacking. Based on the construction of ARG abundance atlas across a > 4,000 km transect in eastern and northern Australia, we found contrasting biogeographic patterns of the phyllosphere and soil resistomes, which showed their distinct responses to the biotic and abiotic stresses. The similarity of ARG compositions in soil, but not in the phyllosphere, exhibited significant distance-decay patterns. ARG abundance in the phyllosphere was mainly correlated with the compositions of co-occurring bacterial, fungal and protistan communities, indicating that biotic stresses were the main drivers shaping the phyllosphere resistome. Soil ARG abundance was mainly associated with abiotic factors including mean annual temperature and precipitation as well as soil total carbon and nitrogen. Our findings demonstrated the distinct roles of biotic and abiotic factors in shaping resistomes in different environmental habitats. These findings constitute a major advance in our understanding of the current environmental resistomes and contribute to better predictions of the evolution of environmental ARGs by highlighting the importance of habitat difference in shaping environmental resistomes.
Collapse
Affiliation(s)
- Zhen-Zhen Yan
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Qing-Lin Chen
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia.
| | - Chao-Yu Li
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Bao-Anh Thi Nguyen
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Yong-Guan Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
| | - Ji-Zheng He
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Hang-Wei Hu
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia.
| |
Collapse
|
24
|
Jordaan K, Lappan R, Dong X, Aitkenhead IJ, Bay SK, Chiri E, Wieler N, Meredith LK, Cowan DA, Chown SL, Greening C. Hydrogen-Oxidizing Bacteria Are Abundant in Desert Soils and Strongly Stimulated by Hydration. mSystems 2020; 5:e01131-20. [PMID: 33203691 PMCID: PMC7677003 DOI: 10.1128/msystems.01131-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 10/29/2020] [Indexed: 01/19/2023] Open
Abstract
How the diverse bacterial communities inhabiting desert soils maintain energy and carbon needs is much debated. Traditionally, most bacteria are thought to persist by using organic carbon synthesized by photoautotrophs following transient hydration events. Recent studies focused on Antarctic desert soils have revealed, however, that some bacteria use atmospheric trace gases, such as hydrogen (H2), to conserve energy and fix carbon independently of photosynthesis. In this study, we investigated whether atmospheric H2 oxidation occurs in four nonpolar desert soils and compared this process to photosynthesis. To do so, we first profiled the distribution, expression, and activities of hydrogenases and photosystems in surface soils collected from the South Australian desert over a simulated hydration-desiccation cycle. Hydrogenase-encoding sequences were abundant in the metagenomes and metatranscriptomes and were detected in actinobacterial, acidobacterial, and cyanobacterial metagenome-assembled genomes. Native dry soil samples mediated H2 oxidation, but rates increased 950-fold following wetting. Oxygenic and anoxygenic phototrophs were also detected in the community but at lower abundances. Hydration significantly stimulated rates of photosynthetic carbon fixation and, to a lesser extent, dark carbon assimilation. Hydrogenase genes were also widespread in samples from three other climatically distinct deserts, the Namib, Gobi, and Mojave, and atmospheric H2 oxidation was also greatly stimulated by hydration at these sites. Together, these findings highlight that H2 is an important, hitherto-overlooked energy source supporting bacterial communities in desert soils. Contrary to our previous hypotheses, however, H2 oxidation occurs simultaneously rather than alternately with photosynthesis in such ecosystems and may even be mediated by some photoautotrophs.IMPORTANCE Desert ecosystems, spanning a third of the earth's surface, harbor remarkably diverse microbial life despite having a low potential for photosynthesis. In this work, we reveal that atmospheric hydrogen serves as a major previously overlooked energy source for a large proportion of desert bacteria. We show that both chemoheterotrophic and photoautotrophic bacteria have the potential to oxidize hydrogen across deserts sampled across four continents. Whereas hydrogen oxidation was slow in native dry deserts, it increased by three orders of magnitude together with photosynthesis following hydration. This study revealed that continual harvesting of atmospheric energy sources may be a major way that desert communities adapt to long periods of water and energy deprivation, with significant ecological and biogeochemical ramifications.
Collapse
Affiliation(s)
- Karen Jordaan
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Rachael Lappan
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Xiyang Dong
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China
| | - Ian J Aitkenhead
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Sean K Bay
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Eleonora Chiri
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | | | - Laura K Meredith
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, USA
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Steven L Chown
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| |
Collapse
|