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Lai Z, Liu Z, Zhao Y, Qin S, Zhang W, Lang T, Zhu Z, Sun Y. Distinct microbial communities under different rock-associated microhabitats in the Qaidam Desert. ENVIRONMENTAL RESEARCH 2024; 250:118462. [PMID: 38367835 DOI: 10.1016/j.envres.2024.118462] [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: 11/30/2023] [Revised: 02/03/2024] [Accepted: 02/09/2024] [Indexed: 02/19/2024]
Abstract
Hypolithic communities, which occupy highly specialised microhabitats beneath translucent rocks in desert and arid environments, have assembly mechanisms and ecosystem functions are not fully understood. Thus, in this study, we aimed to examine the microbial community structure, assembly, and function of light-accessible (under quartz, calcite, and hypolithic lichen-dominated biocrusts) and light-inaccessible microhabitats (under basalt and adjacent soil) in the Qaidam Desert, China. The results showed that hypolithic communities have different characteristics compared with microbial communities of light-inaccessible microhabitats. Notably, hypolithic bacterial communities were dominated by Cyanobacteria, whereas light-inaccessible microhabitats showed a predominance of Bacteroidetes and Proteobacteria. Although the class Dothideomycetes (phylum: Ascomycota) dominated the fungal communities between the two microhabitat types, Sordariomycetes were more prevalent in light-accessible microhabitats. Network and robustness analyses showed that hypolithic communities were less complex and more resilient than microbial communities in light-inaccessible microhabitats. Our results indicated that deterministic processes, specifically homogeneous selection, govern the establishment of bacterial and fungal communities in light-accessible and light-inaccessible microhabitats. The hypolithic community showed an increased frequency of phylotypes that exhibited increased tolerance to functional stress response pathways. In contrast to light-inaccessible microhabitats, light-accessible microhabitats showed a slight decrease and a notable increase in the prevalence of carbon fixation pathways in prokaryotes and carbon fixation in photosynthetic organisms, respectively. For fungi, light-accessible microhabitats enriched saprotrophic and ectomycorrhizal groups. These results highlight the importance of complex and diverse microhabitats in desert regions, which serve as vital shelters for microbes. Combining future research on interactions between hypolithic communities and environments may enhance our current understanding of their pivotal roles in sustaining desert ecosystems. This knowledge then be applied to design and implement informed conservation efforts to preserve these unique rock-associated microhabitats in desert ecosystems.
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Affiliation(s)
- Zongrui Lai
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Zhen Liu
- CAS Engineering Laboratory for Yellow River Delta Modern Agriculture, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yuanyuan Zhao
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Shugao Qin
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Wenqi Zhang
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Tao Lang
- MNR Key Laboratory for Geo-Environmental Monitoring of Great Bay Area & Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, College of Life Sciences and Oceanography, Shenzhen University, 518060, Shenzhen, China; College of Agricultural and Food Engineering, Baise University, Baise, Guangxi 533000, China.
| | - Zhengjie Zhu
- College of Agricultural and Food Engineering, Baise University, Baise, Guangxi 533000, China
| | - Yanfei Sun
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, 570228, China.
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2
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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.
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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
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Mugnai G, Borruso L, Wu YL, Gallinaro M, Cappitelli F, Zerboni A, Villa F. Ecological strategies of bacterial communities in prehistoric stone wall paintings across weathering gradients: A case study from the Borana zone in southern Ethiopia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:168026. [PMID: 37907101 DOI: 10.1016/j.scitotenv.2023.168026] [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: 08/10/2023] [Revised: 09/18/2023] [Accepted: 10/20/2023] [Indexed: 11/02/2023]
Abstract
Rock art paintings represent fragile ecosystems supporting complex microbial communities tuned to the lithic substrate and climatic conditions. The composition and activity of these microbial communities associated with different weathering patterns affecting rock art sites remain unexplored. This study aimed to explore how bacterial communities adapt their ecological strategies based on substrate weathering, while also examining the role of their metabolic pathways in either biodeterioration or bioprotection of the underlying stone. SEM-EDS investigations coupled with 16S rRNA gene sequencing and PICRUSt2 analysis were applied on different weathered surfaces that affect southern Ethiopian rock paintings to investigate the relationships between the current stone microbiome and weathering patterns. The findings revealed that samples experiencing low and high weathering reached a climax stage characterized by stable microenvironments and limited resources. This condition favored K-strategist microorganisms, leading to reduced α-biodiversity and a community with a positive or neutral impact on the substrate. In contrast, moderately-weathered samples displayed diverse microhabitats, resulting in the prevalence of r-strategist bacteria, increased α-biodiversity, and the presence of specialist microorganisms. Moreover, the bacterial communities in moderately-weathered samples demonstrated the highest potential for carbon fixation, stress responses, and complete nitrogen and sulfur cycles. This bacterial community also showed the potential to negatively impact the underlying substrate. This research provided valuable insights into the little-understood ecology of bacterial communities inhabiting deteriorated surfaces, shedding light on the potential role of these microorganisms in the sustainable conservation of rock art.
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Affiliation(s)
- Gianmarco Mugnai
- Department of Agriculture, Food and Environmental Sciences, University of Perugia, Borgo XX Giugno, 74, I-06121 Perugia (PG), IT, Italy.
| | - Luigimaria Borruso
- Free University of Bolzano, Faculty of Agricultural, Environmental and Food Sciences, Piazza Universitá 5, 39100 Bolzano, Italy.
| | - Ying-Li Wu
- Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, 20133 Milan, Italy.
| | - Marina Gallinaro
- Dipartimento di Scienze dell'Antichità, Università di Roma La Sapienza, 00185 Rome, Italy.
| | - Francesca Cappitelli
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano, 20133 Milan, Italy.
| | - Andrea Zerboni
- Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, 20133 Milan, Italy.
| | - Federica Villa
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano, 20133 Milan, Italy.
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4
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Coleine C, Delgado-Baquerizo M, DiRuggiero J, Guirado E, Harfouche AL, Perez-Fernandez C, Singh BK, Selbmann L, Egidi E. Dryland microbiomes reveal community adaptations to desertification and climate change. THE ISME JOURNAL 2024; 18:wrae056. [PMID: 38552152 PMCID: PMC11031246 DOI: 10.1093/ismejo/wrae056] [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: 01/22/2024] [Revised: 03/19/2024] [Accepted: 03/27/2024] [Indexed: 04/21/2024]
Abstract
Drylands account for 45% of the Earth's land area, supporting ~40% of the global population. These regions support some of the most extreme environments on Earth, characterized by extreme temperatures, low and variable rainfall, and low soil fertility. In these biomes, microorganisms provide vital ecosystem services and have evolved distinctive adaptation strategies to endure and flourish in the extreme. However, dryland microbiomes and the ecosystem services they provide are under threat due to intensifying desertification and climate change. In this review, we provide a synthesis of our current understanding of microbial life in drylands, emphasizing the remarkable diversity and adaptations of these communities. We then discuss anthropogenic threats, including the influence of climate change on dryland microbiomes and outline current knowledge gaps. Finally, we propose research priorities to address those gaps and safeguard the sustainability of these fragile biomes.
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Affiliation(s)
- Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, 01100, Italy
| | - Manuel Delgado-Baquerizo
- Laboratorio de Biodiversidad y Funcionamiento Ecosistémico, Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Sevilla, E-41012, Spain
| | - Jocelyne DiRuggiero
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, United States
- Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, United States
| | - Emilio Guirado
- Multidisciplinary Institute for Environment Studies “Ramón Margalef”, Universidad de Alicante, Alicante E-03071, Spain
| | - Antoine L Harfouche
- Department for Innovation in Biological, Agro-Food and Forest systems, University of Tuscia, Viterbo 01100, Italy
| | | | - Brajesh K Singh
- Global Centre for Land-Based Innovation, Western Sydney University, Penrith 2750, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith 2750, Australia
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, 01100, Italy
- Mycological Section, Italian Antarctic National Museum (MNA), Genoa 16128, Italy
| | - Eleonora Egidi
- Global Centre for Land-Based Innovation, Western Sydney University, Penrith 2750, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith 2750, Australia
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5
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Chen JS, Hussain B, Tsai HC, Nagarajan V, Kumar RS, Lin IC, Hsu BM. Deciphering microbial communities and their unique metabolic repertoire across rock-soil-plant continuum in the Dayoukeng fumarolic geothermal field of the Tatun Volcano Group. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:7330-7344. [PMID: 38158533 DOI: 10.1007/s11356-023-31313-x] [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: 05/08/2023] [Accepted: 11/28/2023] [Indexed: 01/03/2024]
Abstract
High temperature and sulfur concentrations in geothermal sulfur fumaroles host unique microbial ecosystems with niche-specific metabolic diversity and physiological functions. In this study, the microbial communities and their functionalities associated with the Dayoukeng geothermal field and the rock-soil-plant continuum were investigated to underpin the microbial modulation at different distances from the fumaroles source. At the phylum level, Bacteroidota, Planctomycetota, Armatimonadota, and Patescibacteria were abundant in plant samples; Elusimicrobiota and Desulfobacterota were in the rock samples while Nitrospirota, Micrarchaeota, and Deinococcota were dominant in the soil samples. Acidophilic thermophiles were enriched in samples within close proximity to the fumaroles, primarily at a distance of 1 m. The sulfur and iron-oxidizing acidophilic bacterial genera such as Acidothiobacillus and Sulfobacillus were abundant in the rock samples. The thermoacidophilic archaeon Acidianus and acidophilic bacteria Acidiphilium were abundant in the soil samples. Additionally, Thermosporothrix and Acidothermus were found abundant in the plant samples. The results of the functional annotation indicated that dark sulfur oxidation, iron oxidation, and hydrogen oxidation pathways were abundant in the soil samples up to 1 m from the fumaroles, while methanogenic and fermentation pathways were more prevalent in the soil samples located 10 m from the fumaroles. Interestingly, the results of this study indicated a higher microbial richness and abundance of acidophilic communities in the soils and plants compared to the rocks of the DYK fumarolic geothermal field.
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Affiliation(s)
- Jung-Sheng Chen
- Department of Medical Research, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Bashir Hussain
- Department of Earth and Environmental Sciences, National Chung Cheng University, Minxiong, Chiayi County, Taiwan
- Department of Biomedical Sciences, National Chung Cheng University, Minxiong, Chiayi County, Taiwan
| | - Hsin-Chi Tsai
- Department of Psychiatry, School of Medicine, Tzu Chi University, Hualien, Taiwan
- Department of Psychiatry, Tzu-Chi General Hospital, Hualien, Taiwan
| | - Viji Nagarajan
- Department of Earth and Environmental Sciences, National Chung Cheng University, Minxiong, Chiayi County, Taiwan
| | - Rajendran Senthil Kumar
- Department of Earth and Environmental Sciences, National Chung Cheng University, Minxiong, Chiayi County, Taiwan
| | - I-Ching Lin
- Department of Family Medicine, Asia University Hospital, Taichung, Taiwan
- Department of Kinesiology, Health and Leisure, Chienkuo Technology University, Chenghua, Taiwan
| | - Bing-Mu Hsu
- Department of Earth and Environmental Sciences, National Chung Cheng University, Minxiong, Chiayi County, Taiwan.
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6
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Moreno-Paz M, dos Santos Severino RS, Sánchez-García L, Manchado JM, García-Villadangos M, Aguirre J, Fernández-Martínez MA, Carrizo D, Kobayashi L, Dave A, Warren-Rhodes K, Davila A, Stoker CR, Glass B, Parro V. Life Detection and Microbial Biomarker Profiling with Signs of Life Detector-Life Detector Chip During a Mars Drilling Simulation Campaign in the Hyperarid Core of the Atacama Desert. ASTROBIOLOGY 2023; 23:1259-1283. [PMID: 37930382 PMCID: PMC10825288 DOI: 10.1089/ast.2021.0174] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 07/02/2023] [Indexed: 11/07/2023]
Abstract
The low organic matter content in the hyperarid core of the Atacama Desert, together with abrupt temperature shifts and high ultraviolet radiation at its surface, makes this region one of the best terrestrial analogs of Mars and one of the best scenarios for testing instrumentation devoted to in situ planetary exploration. We have operated remotely and autonomously the SOLID-LDChip (Signs of Life Detector-Life Detector Chip), an antibody microarray-based sensor instrument, as part of a rover payload during the 2019 NASA Atacama Rover Astrobiology Drilling Studies (ARADS) Mars drilling simulation campaign. A robotic arm collected drilled cuttings down to 80 cm depth and loaded SOLID to process and assay them with LDChip for searching for molecular biomarkers. A remote science team received and analyzed telemetry data and LDChip results. The data revealed the presence of microbial markers from Proteobacteria, Acidobacteria, Bacteroidetes, Actinobacteria, Firmicutes, and Cyanobacteria to be relatively more abundant in the middle layer (40-50 cm). In addition, the detection of several proteins from nitrogen metabolism indicates a pivotal role in the system. These findings were corroborated and complemented on "returned samples" to the lab by a comprehensive analysis that included DNA sequencing, metaproteomics, and a metabolic reconstruction of the sampled area. Altogether, the results describe a relatively complex microbial community with members capable of nitrogen fixation and denitrification, sulfur oxidation and reduction, or triggering oxidative stress responses, among other traits. This remote operation demonstrated the high maturity of SOLID-LDChip as a powerful tool for remote in situ life detection for future missions in the Solar System.
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Affiliation(s)
- Mercedes Moreno-Paz
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
| | - Rita Sofia dos Santos Severino
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
- Departament of Física y Matemáticas y de Automática, University of Alcalá de Henares (UAH), Madrid, Spain
| | - Laura Sánchez-García
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
| | - Juan Manuel Manchado
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
| | | | - Jacobo Aguirre
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
| | - Miguel Angel Fernández-Martínez
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
- Department of Natural Resource Sciences, McGill University, Québec, Canada
| | - Daniel Carrizo
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
| | - Linda Kobayashi
- Space Science Division and Astrobiology Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Arwen Dave
- Space Science Division and Astrobiology Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Kim Warren-Rhodes
- Space Science Division and Astrobiology Division, NASA Ames Research Center, Moffett Field, California, USA
- Carl Sagan Center, SETI Institute, Mountain View, California, USA
| | - Alfonso Davila
- Space Science Division and Astrobiology Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Carol R. Stoker
- Space Science Division and Astrobiology Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Brian Glass
- Space Science Division and Astrobiology Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Víctor Parro
- Department of Molecular Evolution, Centro de Astrobiología (CAB), INTA-CSIC, Madrid, Spain
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Němečková K, Mareš J, Procházková L, Culka A, Košek F, Wierzchos J, Nedbalová L, Dudák J, Tymlová V, Žemlička J, Kust A, Zima J, Nováková E, Jehlička J. Gypsum endolithic phototrophs under moderate climate (Southern Sicily): their diversity and pigment composition. Front Microbiol 2023; 14:1175066. [PMID: 37485515 PMCID: PMC10359912 DOI: 10.3389/fmicb.2023.1175066] [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: 02/27/2023] [Accepted: 05/15/2023] [Indexed: 07/25/2023] Open
Abstract
In this study, we used microscopic, spectroscopic, and molecular analysis to characterize endolithic colonization in gypsum (selenites and white crystalline gypsum) from several sites in Sicily. Our results showed that the dominant microorganisms in these environments are cyanobacteria, including: Chroococcidiopsis sp., Gloeocapsopsis pleurocapsoides, Gloeocapsa compacta, and Nostoc sp., as well as orange pigmented green microalgae from the Stephanospherinia clade. Single cell and filament sequencing coupled with 16S rRNA amplicon metagenomic profiling provided new insights into the phylogenetic and taxonomic diversity of the endolithic cyanobacteria. These organisms form differently pigmented zones within the gypsum. Our metagenomic profiling also showed differences in the taxonomic composition of endoliths in different gypsum varieties. Raman spectroscopy revealed that carotenoids were the most common pigments present in the samples. Other pigments such as gloeocapsin and scytonemin were also detected in the near-surface areas, suggesting that they play a significant role in the biology of endoliths in this environment. These pigments can be used as biomarkers for basic taxonomic identification, especially in case of cyanobacteria. The findings of this study provide new insights into the diversity and distribution of phototrophic microorganisms and their pigments in gypsum in Southern Sicily. Furthemore, this study highlights the complex nature of endolithic ecosystems and the effects of gypsum varieties on these communities, providing additional information on the general bioreceptivity of these environments.
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Affiliation(s)
- Kateřina Němečková
- Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Prague, Czechia
| | - Jan Mareš
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czechia
- Center Algatech, Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czechia
| | - Lenka Procházková
- Department of Ecology, Faculty of Science, Charles University, Prague, Czechia
| | - Adam Culka
- Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Prague, Czechia
| | - Filip Košek
- Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Prague, Czechia
| | - Jacek Wierzchos
- Department of Biochemistry and Microbial Ecology, Museo Nacional de Ciencias Naturales - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Linda Nedbalová
- Department of Ecology, Faculty of Science, Charles University, Prague, Czechia
| | - Jan Dudák
- Institute of Experimental and Applied Physics, Czech Technical University in Prague, Prague, Czechia
| | - Veronika Tymlová
- Institute of Experimental and Applied Physics, Czech Technical University in Prague, Prague, Czechia
| | - Jan Žemlička
- Institute of Experimental and Applied Physics, Czech Technical University in Prague, Prague, Czechia
| | - Andreja Kust
- Department of Earth and Planetary Science, University of Berkeley, Berkeley, CA, United States
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, United States
| | - Jan Zima
- Department of Parasitology, Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Eva Nováková
- Department of Parasitology, Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Jan Jehlička
- Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Prague, Czechia
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Cowan DA, Cary SC, DiRuggiero J, Eckardt F, Ferrari B, Hopkins DW, Lebre PH, Maggs-Kölling G, Pointing SB, Ramond JB, Tribbia D, Warren-Rhodes K. 'Follow the Water': Microbial Water Acquisition in Desert Soils. Microorganisms 2023; 11:1670. [PMID: 37512843 PMCID: PMC10386458 DOI: 10.3390/microorganisms11071670] [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: 05/03/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 07/30/2023] Open
Abstract
Water availability is the dominant driver of microbial community structure and function in desert soils. However, these habitats typically only receive very infrequent large-scale water inputs (e.g., from precipitation and/or run-off). In light of recent studies, the paradigm that desert soil microorganisms are largely dormant under xeric conditions is questionable. Gene expression profiling of microbial communities in desert soils suggests that many microbial taxa retain some metabolic functionality, even under severely xeric conditions. It, therefore, follows that other, less obvious sources of water may sustain the microbial cellular and community functionality in desert soil niches. Such sources include a range of precipitation and condensation processes, including rainfall, snow, dew, fog, and nocturnal distillation, all of which may vary quantitatively depending on the location and geomorphological characteristics of the desert ecosystem. Other more obscure sources of bioavailable water may include groundwater-derived water vapour, hydrated minerals, and metabolic hydro-genesis. Here, we explore the possible sources of bioavailable water in the context of microbial survival and function in xeric desert soils. With global climate change projected to have profound effects on both hot and cold deserts, we also explore the potential impacts of climate-induced changes in water availability on soil microbiomes in these extreme environments.
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Affiliation(s)
- Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
| | - S Craig Cary
- School of Biological Sciences, University of Waikato, Hamilton 3216, New Zealand
| | - Jocelyne DiRuggiero
- Departments of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
- Departments of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Frank Eckardt
- Department of Environmental and Geographical Science, University of Cape Town, Cape Town 7701, South Africa
| | - Belinda Ferrari
- School of Biotechnology and Biological Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - David W Hopkins
- Scotland's Rural College, West Mains Road, Edinburgh EH9 3JG, UK
| | - Pedro H Lebre
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
| | | | - Stephen B Pointing
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Jean-Baptiste Ramond
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
- Departamento Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Dana Tribbia
- School of Biotechnology and Biological Sciences, University of New South Wales, Sydney, NSW 2052, Australia
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9
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Post-dispersal astrobiological events: modelling macroevolutionary dynamics for lithopanspermia. Extremophiles 2023; 27:3. [PMID: 36640217 DOI: 10.1007/s00792-023-01288-1] [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: 06/07/2022] [Accepted: 12/24/2022] [Indexed: 01/15/2023]
Abstract
Lithopanspermia is defined as dispersal of living extremophiles from one planetary body to another, through life-bearing rocks ejected by meteor impacts. If lithopanspermia proves concrete, it should be viewed as an eco-evolutionary phenomenon. Biogeographic/microevolutionary models have been proposed as analogues for lithopanspermia dynamics; however, extremophile arrival on a planetary body is not the end of story. Here, we suggest that eco-evolutionary (environment + organismal microevolution) dynamics can lead to distinct macroevolutionary scenarios after extremophile arrival on a planetary body. Speciation would be the most important factor in interplanetary dynamics due to the possibly long time and distance between dispersive events, similar to long-distance dispersal dynamics on Earth. In previously uninhabited planets, persistence of extremophiles and descendants depends almost only on evolvability of extremophiles against abiotic filters. Considering a previously inhabited planet, ecological interactions at local or global scales could drive persistence (speciation/extinction) of extremophiles in the new habitat. Thus, we might expect high extinction rates if negative interactions are dominant, or, high speciation, if positive interactions occur, with extremophile lineages overpower (or not) the native biota. If interplanetary dispersal is possible, theories about the evolution of life may be universal, leading to a general eco-evolutionary model for life in the Universe.
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Saadouli I, Marasco R, Mejri L, Hamden H, Guerfali MM, Stathopoulou P, Daffonchio D, Cherif A, Ouzari HI, Tsiamis G, Mosbah A. Diversity and adaptation properties of actinobacteria associated with Tunisian stone ruins. Front Microbiol 2022; 13:997832. [PMID: 36583041 PMCID: PMC9793712 DOI: 10.3389/fmicb.2022.997832] [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: 07/19/2022] [Accepted: 11/16/2022] [Indexed: 12/15/2022] Open
Abstract
Stone surface is a unique biological niche that may host a rich microbial diversity. The exploration of the biodiversity of the stone microbiome represents a major challenge and an opportunity to characterize new strains equipped with valuable biological activity. Here, we explored the diversity and adaptation strategies of total bacterial communities associated with Roman stone ruins in Tunisia by considering the effects of geo-climatic regions and stone geochemistry. Environmental 16S rRNA gene amplicon was performed on DNA extracted from stones samples collected in three different sampling sites in Tunisia, along an almost 400km aridity transect, encompassing Mediterranean, semiarid and arid climates. The library was sequenced on an Illumina MiSeq sequencing platform. The cultivable Actinobacteria were isolated from stones samples using the dilution plate technique. A total of 71 strains were isolated and identified based on 16S rRNA gene sequences. Cultivable actinobacteria were further investigated to evaluate the adaptative strategies adopted to survive in/on stones. Amplicon sequencing showed that stone ruins bacterial communities were consistently dominated by Cyanobacteria, followed by Proteobacteria and Actinobacteria along the aridity gradient. However, the relative abundance of the bacterial community components changed according to the geo-climatic origin. Stone geochemistry, particularly the availability of magnesium, chromium, and copper, also influenced the bacterial communities' diversity. Cultivable actinobacteria were further investigated to evaluate the adaptative strategies adopted to survive in/on stones. All the cultivated bacteria belonged to the Actinobacteria class, and the most abundant genera were Streptomyces, Kocuria and Arthrobacter. They were able to tolerate high temperatures (up to 45°C) and salt accumulation, and they produced enzymes involved in nutrients' solubilization, such as phosphatase, amylase, protease, chitinase, and cellulase. Actinobacteria members also had an important role in the co-occurrence interactions among bacteria, favoring the community interactome and stabilization. Our findings provide new insights into actinobacteria's diversity, adaptation, and role within the microbiome associated with stone ruins.
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Affiliation(s)
- Ilhem Saadouli
- Laboratory of Microorganisms and Active Biomolecules, LMBA-LR03ES03, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Ramona Marasco
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Lassaad Mejri
- Laboratory “Energy and Matter for Development of Nuclear Sciences” (LR16CNSTN02), National Center for Nuclear Sciences and Technology, Sidi Thabet Technopark, Sidi Thabet, Tunisia
| | - Haytham Hamden
- Laboratory of Biotechnology and Nuclear Technologies, LR16CNSTN02, National Centre of Nuclear Sciences and Technologies, Sidi Thabet, Tunisia
| | - Meriem M’saad Guerfali
- Laboratory of Biotechnology and Nuclear Technologies, LR16CNSTN02, National Centre of Nuclear Sciences and Technologies, Sidi Thabet, Tunisia
| | - Panagiota Stathopoulou
- Laboratory of Systems Microbiology and Applied Genomics, Department of Sustainable Agriculture, University of Patras, Agrinio, Greece
| | - Daniele Daffonchio
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Ameur Cherif
- BVBGR-LR11ES31, Higher Institute of Biotechnology Sidi Thabet, University of Manouba, Biotechpole Sidi Thabet, Ariana, Tunisia
| | - Hadda-Imene Ouzari
- Laboratory of Microorganisms and Active Biomolecules, LMBA-LR03ES03, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia,*Correspondence: Hadda-Imene Ouzari,
| | - George Tsiamis
- Laboratory of Systems Microbiology and Applied Genomics, Department of Sustainable Agriculture, University of Patras, Agrinio, Greece,George Tsiamis,
| | - Amor Mosbah
- BVBGR-LR11ES31, Higher Institute of Biotechnology Sidi Thabet, University of Manouba, Biotechpole Sidi Thabet, Ariana, Tunisia,Amor Mosbah,
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11
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Iron acquisition and mineral transformation by cyanobacteria living in extreme environments. Mater Today Bio 2022; 17:100493. [PMCID: PMC9682352 DOI: 10.1016/j.mtbio.2022.100493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 10/26/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022] Open
Abstract
Iron is an essential micronutrient for most living organisms, including cyanobacteria. These microorganisms have been found in Earth's driest polar and non-polar deserts, including the Atacama Desert, Chile. Iron-containing minerals were identified in colonized rock substrates from the Atacama Desert, however, the interactions between microorganisms and iron minerals remain unclear. In the current study, we determined that colonized gypsum rocks collected from the Atacama Desert contained both magnetite and hematite phases. A cyanobacteria isolate was cultured on substrates consisting of gypsum with embedded magnetite nanoparticles. Transmission electron microscopy imaging revealed a significant reduction in the size of magnetite nanoparticles due to their dissolution, which occurred around the microbial biofilms. Concurrently, hematite was detected, likely from the oxidation of the magnetite nanoparticles. Higher cell counts and production of siderophores were observed in cultures with magnetite nanoparticles suggesting that cyanobacteria were actively acquiring iron from the magnetite nanoparticles. Magnetite dissolution and iron acquisition by the cyanobacteria was further confirmed using large bulk magnetite crystals, uncovering a survival strategy of cyanobacteria in these extreme environments.
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12
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Villa F, Wu YL, Zerboni A, Cappitelli F. In Living Color: Pigment-Based Microbial Ecology At the Mineral-Air Interface. Bioscience 2022; 72:1156-1175. [PMID: 36451971 PMCID: PMC9699719 DOI: 10.1093/biosci/biac091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Pigment-based color is one of the most important phenotypic traits of biofilms at the mineral-air interface (subaerial biofilms, SABs), because it reflects the physiology of the microbial community. Because color is the hallmark of all SABs, we argue that pigment-based color could convey the mechanisms that drive microbial adaptation and coexistence across different terrestrial environments and link phenotypic traits to community fitness and ecological dynamics. Within this framework, we present the most relevant microbial pigments at the mineral-air interface and discuss some of the evolutionary landscapes that necessitate pigments as adaptive strategies for resource allocation and survivability. We report several pigment features that reflect SAB communities' structure and function, as well as pigment ecology in the context of microbial life-history strategies and coexistence theory. Finally, we conclude the study of pigment-based ecology by presenting its potential application and some of the key challenges in the research.
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Busse L, Tisza M, DiRuggiero J. Viruses Ubiquity and Diversity in Atacama Desert Endolithic Communities. Viruses 2022; 14:v14091983. [PMID: 36146789 PMCID: PMC9500819 DOI: 10.3390/v14091983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 11/16/2022] Open
Abstract
Viruses are key players in the environment, and recent metagenomic studies have revealed their diversity and genetic complexity. Despite progress in understanding the ecology of viruses in extreme environments, viruses’ dynamics and functional roles in dryland ecosystems, which cover about 45% of the Earth’s land surfaces, remain largely unexplored. This study characterizes virus sequences in the metagenomes of endolithic (within rock) microbial communities ubiquitously found in hyper-arid deserts. Taxonomic classification and network construction revealed the presence of novel and diverse viruses in communities inhabiting calcite, gypsum, and ignimbrite rocks. Viral genome maps show a high level of protein diversity within and across endolithic communities and the presence of virus-encoded auxiliary metabolic genes. Phage-host relationships were predicted by matching tRNA, CRISPR spacer, and protein sequences in the viral and microbial metagenomes. Primary producers and heterotrophic bacteria were found to be putative hosts to some viruses. Intriguingly, viral diversity was not correlated with microbial diversity across rock substrates.
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Affiliation(s)
- Leora Busse
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Mike Tisza
- The Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jocelyne DiRuggiero
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
- Correspondence:
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14
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Billi D, Napoli A, Mosca C, Fagliarone C, de Carolis R, Balbi A, Scanu M, Selinger VM, Antonaru LA, Nürnberg DJ. Identification of far-red light acclimation in an endolithic Chroococcidiopsis strain and associated genomic features: Implications for oxygenic photosynthesis on exoplanets. Front Microbiol 2022; 13:933404. [PMID: 35992689 PMCID: PMC9386421 DOI: 10.3389/fmicb.2022.933404] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/28/2022] [Indexed: 11/17/2022] Open
Abstract
Deserts represent extreme habitats where photosynthetic life is restricted to the lithic niche. The ability of rock-inhabiting cyanobacteria to modify their photosynthetic apparatus and harvest far-red light (near-infrared) was investigated in 10 strains of the genus Chroococcidiopsis, previously isolated from diverse endolithic and hypolithic desert communities. The analysis of their growth capacity, photosynthetic pigments, and apcE2-gene presence revealed that only Chroococcidiopsis sp. CCMEE 010 was capable of far-red light photoacclimation (FaRLiP). A total of 15 FaRLiP genes were identified, encoding paralogous subunits of photosystem I, photosystem II, and the phycobilisome, along with three regulatory elements. CCMEE 010 is unique among known FaRLiP strains by undergoing this acclimation process with a significantly reduced cluster, which lacks major photosystem I paralogs psaA and psaB. The identification of an endolithic, extremotolerant cyanobacterium capable of FaRLiP not only contributes to our appreciation of this phenotype’s distribution in nature but also has implications for the possibility of oxygenic photosynthesis on exoplanets.
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Affiliation(s)
- Daniela Billi
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
- *Correspondence: Daniela Billi,
| | - Alessandro Napoli
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
- Ph.D. Program in Cellular and Molecular Biology, Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Claudia Mosca
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | | | | | - Amedeo Balbi
- Department of Physics, University of Rome Tor Vergata, Rome, Italy
| | - Matteo Scanu
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Vera M. Selinger
- Department of Physics, Biochemistry and Biophysics of Photosynthetic Organisms, Freie Universität Berlin, Berlin, Germany
| | - Laura A. Antonaru
- Department of Physics, Biochemistry and Biophysics of Photosynthetic Organisms, Freie Universität Berlin, Berlin, Germany
| | - Dennis J. Nürnberg
- Department of Physics, Biochemistry and Biophysics of Photosynthetic Organisms, Freie Universität Berlin, Berlin, Germany
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15
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Adaptation of Cyanobacteria to the Endolithic Light Spectrum in Hyper-Arid Deserts. Microorganisms 2022; 10:microorganisms10061198. [PMID: 35744716 PMCID: PMC9228357 DOI: 10.3390/microorganisms10061198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/06/2022] [Accepted: 06/08/2022] [Indexed: 02/04/2023] Open
Abstract
In hyper-arid deserts, endolithic microbial communities survive in the pore spaces and cracks of rocks, an environment that enhances water retention and filters UV radiation. The rock colonization zone is enriched in far-red light (FRL) and depleted in visible light. This poses a challenge to cyanobacteria, which are the primary producers of endolithic communities. Many species of cyanobacteria are capable of Far-Red-Light Photoacclimation (FaRLiP), a process in which FRL induces the synthesis of specialized chlorophylls and remodeling of the photosynthetic apparatus, providing the ability to grow in FRL. While FaRLiP has been reported in cyanobacteria from various low-light environments, our understanding of light adaptations for endolithic cyanobacteria remains limited. Here, we demonstrated that endolithic Chroococcidiopsis isolates from deserts around the world synthesize chlorophyll f, an FRL-specialized chlorophyll when FRL is the sole light source. The metagenome-assembled genomes of these isolates encoded chlorophyll f synthase and all the genes required to implement the FaRLiP response. We also present evidence of FRL-induced changes to the major light-harvesting complexes of a Chroococcidiopsis isolate. These findings indicate that endolithic cyanobacteria from hyper-arid deserts use FRL photoacclimation as an adaptation to the unique light transmission spectrum of their rocky habitat.
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16
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Abstract
Arid ecosystems cover ∼40% of the Earth's terrestrial surface and store a high proportion of the global nitrogen (N) pool. They are low-productivity, low-biomass, and polyextreme ecosystems, i.e., with (hyper)arid and (hyper)oligotrophic conditions and high surface UV irradiation and evapotranspiration. These polyextreme conditions severely limit the presence of macrofauna and -flora and, particularly, the growth and productivity of plant species. Therefore, it is generally recognized that much of the primary production (including N-input processes) and nutrient biogeochemical cycling (particularly N cycling) in these ecosystems are microbially mediated. Consequently, we present a comprehensive survey of the current state of knowledge of biotic and abiotic N-cycling processes of edaphic (i.e., open soil, biological soil crust, or plant-associated rhizosphere and rhizosheath) and hypo/endolithic refuge niches from drylands in general, including hot, cold, and polar desert ecosystems. We particularly focused on the microbially mediated biological nitrogen fixation, N mineralization, assimilatory and dissimilatory nitrate reduction, and nitrification N-input processes and the denitrification and anaerobic ammonium oxidation (anammox) N-loss processes. We note that the application of modern meta-omics and related methods has generated comprehensive data sets on the abundance, diversity, and ecology of the different N-cycling microbial guilds. However, it is worth mentioning that microbial N-cycling data from important deserts (e.g., Sahara) and quantitative rate data on N transformation processes from various desert niches are lacking or sparse. Filling this knowledge gap is particularly important, as climate change models often lack data on microbial activity and environmental microbial N-cycling communities can be key actors of climate change by producing or consuming nitrous oxide (N2O), a potent greenhouse gas.
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17
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Gómez-Silva B, Batista-García RA. The Atacama Desert: A Biodiversity Hotspot and Not Just a Mineral-Rich Region. Front Microbiol 2022; 13:812842. [PMID: 35222336 PMCID: PMC8865075 DOI: 10.3389/fmicb.2022.812842] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 01/04/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Benito Gómez-Silva
- Laboratory of Biochemistry, Biomedical Department, Health Sciences Faculty and Centre for Biotechnology and Bioengineering (CeBiB), Universidad de Antofagasta, Antofagasta, Chile
| | - Ramón Alberto Batista-García
- Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
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18
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OUP accepted manuscript. FEMS Microbiol Ecol 2022; 98:6551890. [DOI: 10.1093/femsec/fiac029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 12/22/2021] [Accepted: 03/17/2022] [Indexed: 11/14/2022] Open
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19
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Mehda S, Muñoz-Martín MÁ, Oustani M, Hamdi-Aïssa B, Perona E, Mateo P. Lithic cyanobacterial communities in the polyextreme Sahara Desert: implications for the search for the limits of life. Environ Microbiol 2021; 24:451-474. [PMID: 34837297 DOI: 10.1111/1462-2920.15850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 10/25/2021] [Accepted: 11/12/2021] [Indexed: 11/29/2022]
Abstract
The hyperarid Sahara Desert presents extreme and persistent dry conditions with a limited number of hours during which the moisture availability, temperature and light allow phototrophic growth. Some cyanobacteria can live in these hostile conditions by seeking refuge under (hypolithic) or inside (endolithic) rocks, by colonizing porous spaces (cryptoendoliths) or fissures in stones (chasmoendoliths). Chroococcidiopsis spp. have been reported as the dominant or even the only phototrophs in these hot desert lithic communities. However, the results of this study reveal the high diversity of and variability in cyanobacteria among the sampled habitats in the Sahara Desert. The chasmoendolithic samples presented high coccoid cyanobacteria abundances, although the dominant cyanobacteria were distinct among different locations. A high predominance of a newly described cyanobacterium, Pseudoacaryochloris sahariense, was found in hard, compact, and more opaque stones with cryptoendolithic colonization. On the other hand, the hypolithic samples were dominated by filamentous, non-heterocystous cyanobacteria. Thermophysiological bioassays confirmed desiccation and extreme temperature tolerance as drivers in the cyanobacterial community composition of these lithic niches. The results of the present study provide key factors for understanding life strategies under polyextreme environmental conditions. The isolated strains, especially the newly described cyanobacterium P. sahariense, might represent suitable microorganisms in astrobiology studies aimed at investigating the limits of life.
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Affiliation(s)
- Smail Mehda
- Departamento de Biología. Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Laboratory of Biogeochemistry of Desert Areas, University of Ouargla, Ouargla, 30000, Algeria.,Faculty of Life and Natural Sciences, Department of Agronomy, University of El Oued, El Oued, 39000, Algeria
| | - M Ángeles Muñoz-Martín
- Departamento de Biología. Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Mabrouka Oustani
- Laboratory of Saharan Bio-Resources: Preservation and Development, University of Ouargla, Ouargla, 30000, Algeria
| | - Baelhadj Hamdi-Aïssa
- Laboratory of Biogeochemistry of Desert Areas, University of Ouargla, Ouargla, 30000, Algeria
| | - Elvira Perona
- Departamento de Biología. Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Pilar Mateo
- Departamento de Biología. Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain
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20
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Draft Metagenomes of Endolithic Cyanobacteria and Cohabitants from Hyper-Arid Deserts. Microbiol Resour Announc 2021; 10:e0020621. [PMID: 34323609 PMCID: PMC8320458 DOI: 10.1128/mra.00206-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cyanobacteria are essential to microbial communities inhabiting translucent rocks in hyper-arid deserts. Metagenomic studies revealed unique adaptations of these cyanobacteria, but validation of the corresponding metabolic pathways remained challenging without access to isolates. Here, we present high-quality metagenome-assembled genomes for cyanobacteria, and their heterotrophic companions, isolated from endolithic substrates.
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21
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Amplicon Sequencing of Rock-Inhabiting Microbial Communities from Joshua Tree National Park, USA. Microbiol Resour Announc 2021; 10:e0049421. [PMID: 34165331 PMCID: PMC8223808 DOI: 10.1128/mra.00494-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Endolithic microorganisms have been reported to date in hot and cold drylands worldwide, where they represent the prevailing life forms ensuring ecosystem functionality, playing a paramount role in global biogeochemical processes. We report here an amplicon sequencing characterization of rocks collected from Joshua Tree National Park (JTNP), USA.
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22
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Schulze-Makuch D, Lipus D, Arens FL, Baqué M, Bornemann TLV, de Vera JP, Flury M, Frösler J, Heinz J, Hwang Y, Kounaves SP, Mangelsdorf K, Meckenstock RU, Pannekens M, Probst AJ, Sáenz JS, Schirmack J, Schloter M, Schmitt-Kopplin P, Schneider B, Uhl J, Vestergaard G, Valenzuela B, Zamorano P, Wagner D. Microbial Hotspots in Lithic Microhabitats Inferred from DNA Fractionation and Metagenomics in the Atacama Desert. Microorganisms 2021; 9:microorganisms9051038. [PMID: 34065975 PMCID: PMC8151210 DOI: 10.3390/microorganisms9051038] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/29/2021] [Accepted: 05/05/2021] [Indexed: 01/04/2023] Open
Abstract
The existence of microbial activity hotspots in temperate regions of Earth is driven by soil heterogeneities, especially the temporal and spatial availability of nutrients. Here we investigate whether microbial activity hotspots also exist in lithic microhabitats in one of the most arid regions of the world, the Atacama Desert in Chile. While previous studies evaluated the total DNA fraction to elucidate the microbial communities, we here for the first time use a DNA separation approach on lithic microhabitats, together with metagenomics and other analysis methods (i.e., ATP, PLFA, and metabolite analysis) to specifically gain insights on the living and potentially active microbial community. Our results show that hypolith colonized rocks are microbial hotspots in the desert environment. In contrast, our data do not support such a conclusion for gypsum crust and salt rock environments, because only limited microbial activity could be observed. The hypolith community is dominated by phototrophs, mostly Cyanobacteria and Chloroflexi, at both study sites. The gypsum crusts are dominated by methylotrophs and heterotrophic phototrophs, mostly Chloroflexi, and the salt rocks (halite nodules) by phototrophic and halotolerant endoliths, mostly Cyanobacteria and Archaea. The major environmental constraints in the organic-poor arid and hyperarid Atacama Desert are water availability and UV irradiation, allowing phototrophs and other extremophiles to play a key role in desert ecology.
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Affiliation(s)
- Dirk Schulze-Makuch
- Center for Astronomy and Astrophysics, Technische Universität Berlin, 10623 Berlin, Germany; (F.L.A.); (J.H.); (Y.H.); (J.S.)
- GFZ German Research Centre for Geosciences, Section Geomicrobiology, Telegrafenberg, 14473 Potsdam, Germany; (D.L.); (B.S.)
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Department of Experimental Limnology, 16775 Stechlin, Germany
- School of the Environment, Washington State University, Pullman, WA 99163, USA
- Correspondence: (D.S.-M.); (D.W.); Tel.: +49-(30)-314-23736 (D.S.-M.); +49-(331)-288-28800 (D.W.)
| | - Daniel Lipus
- GFZ German Research Centre for Geosciences, Section Geomicrobiology, Telegrafenberg, 14473 Potsdam, Germany; (D.L.); (B.S.)
| | - Felix L. Arens
- Center for Astronomy and Astrophysics, Technische Universität Berlin, 10623 Berlin, Germany; (F.L.A.); (J.H.); (Y.H.); (J.S.)
| | - Mickael Baqué
- German Aerospace Center (DLR), Institute of Planetary Research, 12489 Berlin, Germany;
| | - Till L. V. Bornemann
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141 Essen, Germany; (T.L.V.B.); (J.F.); (R.U.M.); (M.P.); (A.J.P.)
| | - Jean-Pierre de Vera
- German Aerospace Center (DLR), Microgravity User Support Center (MUSC), 51147 Cologne, Germany;
| | - Markus Flury
- Department of Crop and Soil Science, Washington State University, Pullman, WA 99164, USA;
- Department of Crop and Soil Science, Washington State University, Puyallup, WA 98371, USA
| | - Jan Frösler
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141 Essen, Germany; (T.L.V.B.); (J.F.); (R.U.M.); (M.P.); (A.J.P.)
| | - Jacob Heinz
- Center for Astronomy and Astrophysics, Technische Universität Berlin, 10623 Berlin, Germany; (F.L.A.); (J.H.); (Y.H.); (J.S.)
| | - Yunha Hwang
- Center for Astronomy and Astrophysics, Technische Universität Berlin, 10623 Berlin, Germany; (F.L.A.); (J.H.); (Y.H.); (J.S.)
| | - Samuel P. Kounaves
- Department of Chemistry, Tufts University, Boston, MA 02155, USA;
- Department of Earth Science & Engineering, Imperial College London, London SW7 2AZ, UK
| | - Kai Mangelsdorf
- GFZ German Research Centre for Geosciences, Section Organic Geochemistry, 14473 Potsdam, Germany;
| | - Rainer U. Meckenstock
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141 Essen, Germany; (T.L.V.B.); (J.F.); (R.U.M.); (M.P.); (A.J.P.)
| | - Mark Pannekens
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141 Essen, Germany; (T.L.V.B.); (J.F.); (R.U.M.); (M.P.); (A.J.P.)
| | - Alexander J. Probst
- Environmental Microbiology and Biotechnology, Department of Chemistry, University of Duisburg-Essen, 45141 Essen, Germany; (T.L.V.B.); (J.F.); (R.U.M.); (M.P.); (A.J.P.)
| | - Johan S. Sáenz
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; (J.S.S.); (M.S.)
| | - Janosch Schirmack
- Center for Astronomy and Astrophysics, Technische Universität Berlin, 10623 Berlin, Germany; (F.L.A.); (J.H.); (Y.H.); (J.S.)
| | - Michael Schloter
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; (J.S.S.); (M.S.)
| | - Philippe Schmitt-Kopplin
- Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; (P.-S.K.); (J.U.)
| | - Beate Schneider
- GFZ German Research Centre for Geosciences, Section Geomicrobiology, Telegrafenberg, 14473 Potsdam, Germany; (D.L.); (B.S.)
- Federal Institute for Materials Research and Testing (BAM), 12205 Berlin, Germany
| | - Jenny Uhl
- Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; (P.-S.K.); (J.U.)
| | - Gisle Vestergaard
- Department of Health Technology, Technical University of Denmark, 2800 Lyngby, Denmark;
| | - Bernardita Valenzuela
- Laboratorio de Microorganismos Extremófilos, Instituto Antofagasta, Universidad de Antofagasta, Av. Angamos 601, Antofagasta 1240000, Chile; (B.V.); (P.Z.)
| | - Pedro Zamorano
- Laboratorio de Microorganismos Extremófilos, Instituto Antofagasta, Universidad de Antofagasta, Av. Angamos 601, Antofagasta 1240000, Chile; (B.V.); (P.Z.)
| | - Dirk Wagner
- GFZ German Research Centre for Geosciences, Section Geomicrobiology, Telegrafenberg, 14473 Potsdam, Germany; (D.L.); (B.S.)
- Institute of Geosciences, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
- Correspondence: (D.S.-M.); (D.W.); Tel.: +49-(30)-314-23736 (D.S.-M.); +49-(331)-288-28800 (D.W.)
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23
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Khomutovska N, de los Ríos A, Syczewski MD, Jasser I. Connectivity of Edaphic and Endolithic Microbial Niches in Cold Mountain Desert of Eastern Pamir (Tajikistan). BIOLOGY 2021; 10:314. [PMID: 33918726 PMCID: PMC8069199 DOI: 10.3390/biology10040314] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 03/31/2021] [Accepted: 04/06/2021] [Indexed: 01/04/2023]
Abstract
Microbial communities found in arid environments are commonly represented by biological soil crusts (BSCs) and endolithic assemblages. There is still limited knowledge concerning endoliths and BSCs occurring in the cold mountain desert of Pamir. The aim of the study was to investigate the composition and structure of endolithic bacterial communities in comparison to surrounding BSCs in three subregions of the Eastern Pamir (Tajikistan). The endolithic and BSC communities were studied using culture-independent and culture-dependent techniques. The structure of the endolithic bacterial communities can be characterized as Actinobacteria-Proteobacteria-Bacteroidetes-Chloroflexi-Cyanobacteria, while the BSCs' can be described as Proteobacteria-Actinobacteria-Bacteroidetes-Cyanobacteria assemblages with low representation of other bacteria. The endolithic cyanobacterial communities were characterized by the high percentage of Chroococcidiopsaceae, Nodosilineaceae, Nostocaceae and Thermosynechococcaceae, while in the BSCs were dominated by Nodosilineaceae, Phormidiaceae and Nostocaceae. The analysis of 16S rRNA genes of the cyanobacterial cultures revealed the presence of possibly novel species of Chroococcidiopsis, Gloeocapsopsis and Wilmottia. Despite the niches' specificity, which is related to the influence of microenvironment factors on the composition and structure of endolithic communities, our results illustrate the interrelation between the endoliths and the surrounding BSCs in some regions. The structure of cyanobacterial communities from BSC was the only one to demonstrate some subregional differences.
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Affiliation(s)
- Nataliia Khomutovska
- Institute of Environmental Biology, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland;
| | - Asunción de los Ríos
- Department of Biogeochemistry and Microbial Ecology, The National Museum of Natural Sciences-CSIC, 28006 Madrid, Spain;
| | - Marcin D. Syczewski
- Institute of Geochemistry, Mineralogy and Petrology, Faculty of Geology, University of Warsaw, 02-089 Warsaw, Poland;
| | - Iwona Jasser
- Institute of Environmental Biology, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland;
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24
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Coleine C, Biagioli F, de Vera JP, Onofri S, Selbmann L. Endolithic microbial composition in Helliwell Hills, a newly investigated Mars-like area in Antarctica. Environ Microbiol 2021; 23:4002-4016. [PMID: 33538384 DOI: 10.1111/1462-2920.15419] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 01/04/2023]
Abstract
The diversity and composition of Antarctic cryptoendolithic microbial communities in the Mars-analogue site of Helliwell Hills (Northern Victoria Land, Continental Antarctica) are investigated, for the first time, applying both culture-dependent and high-throughput sequencing approaches. The study includes all the domains of the tree of life: Eukaryotes, Bacteria and Archaea to give a complete overview of biodiversity and community structure. Furthermore, to explore the geographic distribution of endoliths throughout the Victoria Land (Continental Antarctica), we compared the fungal and bacterial community composition and structure of endolithically colonized rocks, collected in >30 sites in 10 years of Italian Antarctic Expeditions. Compared with the fungi and other eukaryotes, the prokaryotic communities were richer in species, more diverse and highly heterogeneous. Despite the diverse community compositions, shared populations were found and were dominant in all sites. Local diversification was observed and included prokaryotes as members of Alphaproteobacteria and Crenarchaeota (Archaea), the last detected for the first time in these cryptoendolithic communities. Few eukaryotes, namely lichen-forming fungal species as Lecidella grenii, were detected in Helliwell Hills only. These findings suggest that geographic distance and isolation in these remote areas may promote the establishment of peculiar locally diversified microorganisms.
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Affiliation(s)
- Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Federico Biagioli
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Jean Pierre de Vera
- German Aerospace Center (DLR), Institute of Planetary Research, Planetary Laboratories, Research Group Astrobiological Laboratories, Berlin, Germany
| | - Silvano Onofri
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy.,Italian Antarctic National Museum (MNA), Mycological Section, Genoa, Italy
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25
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Ennis NJ, Dharumaduri D, Bryce JG, Tisa LS. Metagenome Across a Geochemical Gradient of Indian Stone Ruins Found at Historic Sites in Tamil Nadu, India. MICROBIAL ECOLOGY 2021; 81:385-395. [PMID: 32918562 DOI: 10.1007/s00248-020-01598-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 06/11/2023]
Abstract
Although stone surfaces seem unlikely to be habitable, they support microbial life. Life on these surfaces are subjected to many varying harsh conditions and require the inhabitants to exhibit resistance to environmental factors including UV irradiation, toxic metal exposure, and fluctuating temperatures and humidity. Here we report the effect of hosting stone geochemistry on the microbiome of stone ruins found in Tamil Nadu, India. The microbial communities found on the two lithologies, granite and granodiorite, hosted distinct populations of bacteria. Geochemical composition analysis of sampled stones revealed quartz mineral content as a major driver of microbial community structure, particularly promoting community richness and proportions of Cyanobacteria and Deinococcus-Thermus. Other geochemical parameters including ilmenite, albite, anorthite, and orthoclase components or elemental concentrations (Ti, Fe, Mn, Na, and K) also influenced community structure to a lesser degree than quartz. Core members of the stone microbiome community found on both lithologies were also identified and included Cyanobacteria (Chroococcidiopsaceae and Dapisostemonum CCIBt 3536), Rubrobacter, and Deinococcus. A cluster of taxa including Sphingomonas, Geodermatophilus, and Truepera were mostly found in the granodiorite samples. Community diversity correlated with quartz mineral content in these samples may indicate that the microbial communities that attach to quartz surfaces may be transient and regularly changing. This work has expanded our understanding of built-stone microbial community structure based on lithology and geochemistry.
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Affiliation(s)
- Nathaniel J Ennis
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH, 03824-2617, USA
| | - Dhanasekaran Dharumaduri
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH, 03824-2617, USA
- Department of Microbiology, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India
| | - Julia G Bryce
- Department of Earth Sciences, University of New Hampshire, Durham, 03824, NH, USA
| | - Louis S Tisa
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, 46 College Rd., Durham, NH, 03824-2617, USA.
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26
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Fanelli G, Coleine C, Gevi F, Onofri S, Selbmann L, Timperio AM. Metabolomics of Dry Versus Reanimated Antarctic Lichen-Dominated Endolithic Communities. Life (Basel) 2021; 11:96. [PMID: 33514042 PMCID: PMC7911838 DOI: 10.3390/life11020096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/18/2021] [Accepted: 01/25/2021] [Indexed: 12/31/2022] Open
Abstract
Cryptoendolithic communities are almost the sole life form in the ice-free areas of the Antarctic desert, encompassing among the most extreme-tolerant organisms known on Earth that still assure ecosystems functioning, regulating nutrient and biogeochemical cycles under conditions accounted as incompatible with active life. If high-throughput sequencing based studies are unravelling prokaryotic and eukaryotic diversity, they are not yet characterized in terms of stress adaptations and responses, despite their paramount ecological importance. In this study, we compared the responses of Antarctic endolithic communities, with special focus on fungi, both under dry conditions (i.e., when dormant), and after reanimation by wetting, light, and optimal temperature (15 °C). We found that several metabolites were differently expressed in reanimated opposite sun exposed communities, suggesting a critical role in their success. In particular, the saccharopine pathway was up-regulated in the north surface, while the spermine/spermidine pathway was significantly down-regulated in the shaded exposed communities. The carnitine-dependent pathway is up-regulated in south-exposed reanimated samples, indicating the preferential involvement of the B-oxidation for the functioning of TCA cycle. The role of these metabolites in the performance of the communities is discussed herein.
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Affiliation(s)
- Giuseppina Fanelli
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy; (G.F.); (C.C.); (F.G.); (S.O.)
| | - Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy; (G.F.); (C.C.); (F.G.); (S.O.)
| | - Federica Gevi
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy; (G.F.); (C.C.); (F.G.); (S.O.)
| | - Silvano Onofri
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy; (G.F.); (C.C.); (F.G.); (S.O.)
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy; (G.F.); (C.C.); (F.G.); (S.O.)
- Italian National Antarctic Museum (MNA), Mycological Section, 16166 Genoa, Italy
| | - Anna Maria Timperio
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy; (G.F.); (C.C.); (F.G.); (S.O.)
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27
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Casero MC, Ascaso C, Quesada A, Mazur-Marzec H, Wierzchos J. Response of Endolithic Chroococcidiopsis Strains From the Polyextreme Atacama Desert to Light Radiation. Front Microbiol 2021; 11:614875. [PMID: 33537015 PMCID: PMC7848079 DOI: 10.3389/fmicb.2020.614875] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/28/2020] [Indexed: 01/09/2023] Open
Abstract
Cyanobacteria exposed to high solar radiation make use of a series of defense mechanisms, including avoidance, antioxidant systems, and the production of photoprotective compounds such as scytonemin. Two cyanobacterial strains of the genus Chroococcidiopsis from the Atacama Desert - which has one of the highest solar radiation levels on Earth- were examined to determine their capacity to protect themselves from direct photosynthetically active (PAR) and ultraviolet radiation (UVR): the UAM813 strain, originally isolated from a cryptoendolithic microhabitat within halite (NaCl), and UAM816 strain originally isolated from a chasmoendolithic microhabitat within calcite (CaCO3). The oxidative stress induced by exposure to PAR or UVR + PAR was determined to observe their short-term response, as were the long-term scytonemin production, changes in metabolic activity and ultrastructural damage induced. Both strains showed oxidative stress to both types of light radiation. The UAM813 strain showed a lower acclimation capacity than the UAM816 strain, showing an ever-increasing accumulation of reactive oxygen species (ROS) and a smaller accumulation of scytonemin. This would appear to reflect differences in the adaptation strategies followed to meet the demands of their different microhabitats.
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Affiliation(s)
- María Cristina Casero
- Grupo de Ecología y Geomicrobiología del Sustrato Lítico, Departamento de Biogeoquímica y Ecología Microbiana, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
| | - Carmen Ascaso
- Grupo de Ecología y Geomicrobiología del Sustrato Lítico, Departamento de Biogeoquímica y Ecología Microbiana, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
| | - Antonio Quesada
- Departamento de Biología, Universidad Autónoma de Madrid, Madrid, Spain
| | | | - Jacek Wierzchos
- Grupo de Ecología y Geomicrobiología del Sustrato Lítico, Departamento de Biogeoquímica y Ecología Microbiana, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
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28
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Choe YH, Kim M, Lee YK. Distinct Microbial Communities in Adjacent Rock and Soil Substrates on a High Arctic Polar Desert. Front Microbiol 2021; 11:607396. [PMID: 33488547 PMCID: PMC7819959 DOI: 10.3389/fmicb.2020.607396] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/08/2020] [Indexed: 01/04/2023] Open
Abstract
Understanding microbial niche variability in polar regions can provide insights into the adaptive diversification of microbial lineages in extreme environments. Compositions of microbial communities in Arctic soils are well documented but a comprehensive multidomain diversity assessment of rocks remains insufficiently studied. In this study, we obtained two types of rocks (sandstone and limestone) and soils around the rocks in a high Arctic polar desert (Svalbard), and examined the compositions of archaeal, bacterial, fungal, and protistan communities in the rocks and soils. The microbial community structure differed significantly between rocks and soils across all microbial groups at higher taxonomic levels, indicating that Acidobacteria, Gemmatimonadetes, Latescibacteria, Rokubacteria, Leotiomycetes, Pezizomycetes, Mortierellomycetes, Sarcomonadea, and Spirotrichea were more abundant in soils, whereas Cyanobacteria, Deinococcus-Thermus, FBP, Lecanoromycetes, Eurotiomycetes, Trebouxiophyceae, and Ulvophyceae were more abundant in rocks. Interestingly, fungal communities differed markedly between two different rock types, which is likely to be ascribed to the predominance of distinct lichen-forming fungal taxa (Verrucariales in limestone, and Lecanorales in sandstone). This suggests that the physical or chemical properties of rocks could be a major determinant in the successful establishment of lichens in lithic environments. Furthermore, the biotic interactions among microorganisms based on co-occurrence network analysis revealed that Polyblastia and Verrucaria in limestone, and Atla, Porpidia, and Candelariella in sandstone play an important role as keystone taxa in the lithic communities. Our study shows that even in niches with the same climate regime and proximity to each other, heterogeneity of edaphic and lithic niches can affect microbial community assembly, which could be helpful in comprehensively understanding the effects of niche on microbial assembly in Arctic terrestrial ecosystems.
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Affiliation(s)
- Yong-Hoe Choe
- Korea Polar Research Institute, Incheon, South Korea
| | - Mincheol Kim
- Korea Polar Research Institute, Incheon, South Korea
| | - Yoo Kyung Lee
- Korea Polar Research Institute, Incheon, South Korea
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29
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Popović S, Nikolić N, Predojević D, Jakovljević O, Rađa T, Anđelković A, Subakov-Simić G. Endolithic phototrophs: Examples from cave-like environments. KRAGUJEVAC JOURNAL OF SCIENCE 2021. [DOI: 10.5937/kgjsci2143123p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Endoliths are more frequently found in extremely harsh environments, but they can inhabit mesic climate and subterranean habitats as well. Whether they are adapted to life inside rocks or do they seek refuge in this way, remains largely unknown for caves and pits. Consequently, subterranean habitats in limestone areas, were explored: three caves in Serbia (Cerjanska, Petnička and Potpeć) and one pit in Croatia (Keranova Golubinka). Sampling of rock substratum containing endoliths was performed at various distances from the entrance, at sites characterized by a lower level of light intensity. Phototrophs were separated from the rock matrix using 10% hydrochloric acid and analyzed using light microscopy. In general, low diversity of endoliths was observed, but representatives from Cyanobacteria, Chlorophyta and Xanthophyta were found. Cyanobacteria, more precisely coccoid forms (genera Aphanocapsa, Chroococcidiopsis, Gloeocapsa, Gloeocapsopsis, Synechococcus), were dominant. The most interesting cyanobacterial taxon, Leptolyngbya-like taxon, representing a true endolith (euendolith), was found in the Petnička Cave. This taxon and its relation to the substratum, as well as chasmoendolithic community from the Keranova Golubinka Pit, were observed using Scanning electron microscopy (SEM). It was observed that chasmoendoliths inhabit already existing surface rock cracks and fissures, while a true endolith actively bores into the substratum. Non-metric multidimensional scaling (NMDS) was performed to observe the similarity between the sampling sites. Endoliths can grow inside the rocks, making them very successful biodeteriogens, which is not a desirable trait for caves and pits that are characterized by various attractive geomorphological features that need to be preserved. Thus, considering these habitats, more attention should be paid to the endolith community in the future.
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30
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Khomutovska N, de los Ríos A, Jasser I. Diversity and Colonization Strategies of Endolithic Cyanobacteria in the Cold Mountain Desert of Pamir. Microorganisms 2020; 9:microorganisms9010006. [PMID: 33375046 PMCID: PMC7822004 DOI: 10.3390/microorganisms9010006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/06/2020] [Accepted: 12/18/2020] [Indexed: 12/16/2022] Open
Abstract
Microorganisms can survive in extreme environments and oligotrophic habitats thanks to their specific adaptive capacity. Due to its severe and contrasting climate conditions, the cold mountain desert in Eastern Pamir provides a unique environment for analyzing microbial adaptation mechanisms occurring within colonization of endolithic habitats. This study aims to investigate the composition and structure of endolithic microbial communities and analyze the interactions between microorganisms and colonized lithic substrates. Endolithic biofilms were examined using scanning electron microscopy in backscattered electron mode (SEM-BSE) and next-generation sequencing (NGS) applying amplicon sequence variants (ASVs) approach. The investigation of the V3–V4 region of 16S rRNA gene revealed that endolithic communities are dominated by Actinobacteria (26%), Proteobacteria (23%), and Cyanobacteria (11.4%). Cyanobacteria were represented by Oxyphotobacteria with a predominance of subclasses of Oscillatoriophycidae, Synechococcophycideae, and Nostocophycidae as well as the rarely occurring Sericytochromatia. The positive correlation between the contribution of the orders Synechococcales and Rhizobiales to community structure suggests that some functionally closed taxa of Cyanobacteria and Proteobacteria can complement each other, for example, in nitrogen fixation in endolithic communities. The endolithic communities occurring in Eastern Pamir were identified as complex systems whose composition and structure seem to be influenced by the architecture of microhabitats and related microenvironmental conditions.
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Affiliation(s)
- Nataliia Khomutovska
- Department of Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland;
- Correspondence: ; Tel.: +48-22-55-26-580
| | - Asunción de los Ríos
- Department of Biogeochemistry and Microbial Ecology, The National Museum of Natural Sciences-CSIC, 28006 Madrid, Spain;
| | - Iwona Jasser
- Department of Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland;
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31
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Ertekin E, Meslier V, Browning A, Treadgold J, DiRuggiero J. Rock structure drives the taxonomic and functional diversity of endolithic microbial communities in extreme environments. Environ Microbiol 2020; 23:3937-3956. [PMID: 33078515 DOI: 10.1111/1462-2920.15287] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 10/07/2020] [Accepted: 10/18/2020] [Indexed: 11/29/2022]
Abstract
Endolithic (rock-dwelling) microbial communities are ubiquitous in hyper-arid deserts around the world and the last resort for life under extreme aridity. These communities are excellent models to explore biotic and abiotic drivers of diversity because they are of low complexity. Using high-throughput amplicon and metagenome sequencing, combined with X-ray computed tomography, we investigated how water availability and substrate architecture modulated the taxonomic and functional composition of gypsum endolithic communities in the Atacama Desert, Chile. We found that communities inhabiting gypsum rocks with a more fragmented substrate architecture had higher taxonomic and functional diversity, despite having less water available. This effect was tightly linked with community connectedness and likely the result of niche differentiation. Gypsum communities were functionally similar, yet adapted to their unique micro-habitats by modulating their carbon and energy acquisition strategies and their growth modalities. Reconstructed population genomes showed that these endolithic microbial populations encoded potential pathways for anoxygenic phototrophy and atmospheric hydrogen oxidation as supplemental energy sources.
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Affiliation(s)
- Emine Ertekin
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Victoria Meslier
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA.,MetaGenoPolis, Jouy-en-Josas, France
| | | | | | - Jocelyne DiRuggiero
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA.,Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD, USA
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32
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Coleine C, Stajich JE, de Los Ríos A, Selbmann L. Beyond the extremes: Rocks as ultimate refuge for fungi in drylands. Mycologia 2020; 113:108-133. [PMID: 33232202 DOI: 10.1080/00275514.2020.1816761] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In an era of rapid climate change and expansion of desertification, the extremely harsh conditions of drylands are a true challenge for microbial life. Under drought conditions, where most life forms cannot survive, rocks represent the main refuge for life. Indeed, the endolithic habitat provides thermal buffering, physical stability, and protection against incident ultraviolet (UV) radiation and solar radiation and, to some extent, ensures water retention to microorganisms. The study of these highly specialized extreme-tolerant and extremophiles may provide tools for understanding microbial interactions and processes that allow them to keep their metabolic machinery active under conditions of dryness and oligotrophy that are typically incompatible with active life, up to the dry limits for life. Despite lithobiontic communities being studied all over the world, a comprehensive understanding of their ecology, evolution, and adaptation is still nascent. Herein, we survey the fungal component of these microbial ecosystems. We first provide an overview of the main defined groups (i.e., lichen-forming fungi, black fungi, and yeasts) of the most known and studied Antarctic endolithic communities that are almost the only life forms ensuring ecosystem functionality in the ice-free areas of the continent. For each group, we discuss their main traits and their diversity. Then, we focus on the fungal taxonomy and ecology of other worldwide endolithic communities. Finally, we highlight the utmost importance of a global rock survey in order to have a comprehensive view of the diversity, distribution, and functionality of these fungi in drylands, to obtain tools in desert area management, and as early alarm systems to climate change.
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Affiliation(s)
- Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia , Largo dell'Università snc, 01100, Viterbo, Italy
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, University of California, 900 University Ave , Riverside, California 92521
| | - Asunción de Los Ríos
- Department of Biogeochemistry and Microbial Ecology, Museo Nacional de Ciencias Naturales, Spanish National Resource Council, Madrid, Spain
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia , Largo dell'Università snc, 01100, Viterbo, Italy.,Italian National Antarctic Museum, Mycological Section, Genoa, Italy
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33
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Uritskiy G, Munn A, Dailey M, Gelsinger DR, Getsin S, Davila A, McCullough PR, Taylor J, DiRuggiero J. Environmental Factors Driving Spatial Heterogeneity in Desert Halophile Microbial Communities. Front Microbiol 2020; 11:578669. [PMID: 33193201 PMCID: PMC7606970 DOI: 10.3389/fmicb.2020.578669] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/24/2020] [Indexed: 12/22/2022] Open
Abstract
Spatial heterogeneity in microbial communities is observed in all natural ecosystems and can stem from both adaptations to local environmental conditions as well as stochastic processes. Extremophile microbial communities inhabiting evaporitic halite nodules (salt rocks) in the Atacama Desert, Chile, are a good model ecosystem for investigating factors leading to microbiome heterogeneity, due to their diverse taxonomic composition and the spatial segregation of individual nodules. We investigated the abiotic factors governing microbiome composition across different spatial scales, allowing for insight into the factors that govern halite colonization from regional desert-wide scales to micro-scales within individual nodules. We found that water availability and community drift account for microbiome assembly differently at different distance scales, with higher rates of cell dispersion at the smaller scales resulting in a more homogenous composition. This trend likely applies to other endoliths, and to non-desert communities, where dispersion between communities is limited. At the intra-nodule scales, a light availability gradient was most important in determining the distribution of microbial taxa despite intermixing by water displacement via capillary action.
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Affiliation(s)
- Gherman Uritskiy
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Adam Munn
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Micah Dailey
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Diego R Gelsinger
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Samantha Getsin
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Alfonso Davila
- NASA Ames Research Center, Moffett Field, CA, United States
| | - P R McCullough
- Department of Physics and Astronomy, Johns Hopkins University, and Space Telescope Science Institute, Baltimore, MD, United States
| | - James Taylor
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States.,Department of Computer Science, Johns Hopkins University, Baltimore, MD, United States
| | - Jocelyne DiRuggiero
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States.,Department of Earth & Planetary Sciences, Johns Hopkins University, Baltimore, MD, United States
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34
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Crystalline water in gypsum is unavailable for cyanobacteria in laboratory experiments and in natural desert endolithic habitats. Proc Natl Acad Sci U S A 2020; 117:27786-27787. [PMID: 33093212 DOI: 10.1073/pnas.2013134117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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35
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Identification, biochemical composition and phycobiliproteins production of Chroococcidiopsis sp. from arid environment. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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36
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Huang W, Ertekin E, Wang T, Cruz L, Dailey M, DiRuggiero J, Kisailus D. Mechanism of water extraction from gypsum rock by desert colonizing microorganisms. Proc Natl Acad Sci U S A 2020; 117:10681-10687. [PMID: 32366642 PMCID: PMC7245118 DOI: 10.1073/pnas.2001613117] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Microorganisms, in the most hyperarid deserts around the world, inhabit the inside of rocks as a survival strategy. Water is essential for life, and the ability of a rock substrate to retain water is essential for its habitability. Here we report the mechanism by which gypsum rocks from the Atacama Desert, Chile, provide water for its colonizing microorganisms. We show that the microorganisms can extract water of crystallization (i.e., structurally ordered) from the rock, inducing a phase transformation from gypsum (CaSO4·2H2O) to anhydrite (CaSO4). To investigate and validate the water extraction and phase transformation mechanisms found in the natural geological environment, we cultivated a cyanobacterium isolate on gypsum rock samples under controlled conditions. We found that the cyanobacteria attached onto high surface energy crystal planes ({011}) of gypsum samples generate a thin biofilm that induced mineral dissolution accompanied by water extraction. This process led to a phase transformation to an anhydrous calcium sulfate, anhydrite, which was formed via reprecipitation and subsequent attachment and alignment of nanocrystals. Results in this work not only shed light on how microorganisms can obtain water under severe xeric conditions but also provide insights into potential life in even more extreme environments, such as Mars, as well as offering strategies for advanced water storage methods.
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Affiliation(s)
- Wei Huang
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521
| | - Emine Ertekin
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
| | - Taifeng Wang
- Materials Science and Engineering Program, University of California, Riverside, CA 92521
| | - Luz Cruz
- Materials Science and Engineering Program, University of California, Riverside, CA 92521
| | - Micah Dailey
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
| | | | - David Kisailus
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521;
- Materials Science and Engineering Program, University of California, Riverside, CA 92521
- Department of Materials Science and Engineering, University of California, Irvine, CA 92697
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37
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Uritskiy G, Tisza MJ, Gelsinger DR, Munn A, Taylor J, DiRuggiero J. Cellular life from the three domains and viruses are transcriptionally active in a hypersaline desert community. Environ Microbiol 2020; 23:3401-3417. [DOI: 10.1111/1462-2920.15023] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 04/12/2020] [Indexed: 02/03/2023]
Affiliation(s)
- Gherman Uritskiy
- Department of Biology Johns Hopkins University Baltimore MD 21218 USA
| | - Michael J. Tisza
- Department of Biology Johns Hopkins University Baltimore MD 21218 USA
- Laboratory of Cellular Oncology NCI, NIH Bethesda MD 20892‐4263 USA
| | | | - Adam Munn
- Department of Biology Johns Hopkins University Baltimore MD 21218 USA
| | - James Taylor
- Department of Biology Johns Hopkins University Baltimore MD 21218 USA
- Department of Computer Science Johns Hopkins University Baltimore MD 21218 USA
| | - Jocelyne DiRuggiero
- Department of Biology Johns Hopkins University Baltimore MD 21218 USA
- Department of Earth and Planetary Sciences Johns Hopkins University Baltimore MD 21218 USA
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38
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Flores N, Hoyos S, Venegas M, Galetović A, Zúñiga LM, Fábrega F, Paredes B, Salazar-Ardiles C, Vilo C, Ascaso C, Wierzchos J, Souza-Egipsy V, Araya JE, Batista-García RA, Gómez-Silva B. Haloterrigena sp. Strain SGH1, a Bacterioruberin-Rich, Perchlorate-Tolerant Halophilic Archaeon Isolated From Halite Microbial Communities, Atacama Desert, Chile. Front Microbiol 2020; 11:324. [PMID: 32194531 PMCID: PMC7066086 DOI: 10.3389/fmicb.2020.00324] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 02/14/2020] [Indexed: 11/16/2022] Open
Abstract
An extreme halophilic archaeon, strain SGH1, is a novel microorganism isolated from endolithic microbial communities colonizing halites at Salar Grande, Atacama Desert, in northern Chile. Our study provides structural, biochemical, genomic, and physiological information on this new isolate living at the edge of the physical and chemical extremes at the Atacama Desert. SGH1 is a Gram-negative, red-pigmented, non-motile unicellular coccoid organism. Under the transmission electron microscope, strain SGH1 showed an abundant electro-dense material surrounding electron-lucent globular structures resembling gas vacuoles. Strain SGH1 showed a 16S rRNA gene sequence with a close phylogenetic relationship to the extreme halophilic archaea Haloterrigena turkmenica and Haloterrigena salina and has been denominated Haloterrigena sp. strain SGH1. Strain SGH1 grew at 20-40°C (optimum 37°C), at salinities between 15 and 30% (w/v) NaCl (optimum 25%) and growth was improved by addition of 50 mM KCl and 0.5% w/v casamino acids. Growth was severely restricted at salinities below 15% NaCl and cell lysis is avoided at a minimal 10% NaCl. Maximal concentrations of magnesium chloride and sodium or magnesium perchlorates that supported SGH1 growth were 0.5 and 0.15M, respectively. Haloterrigena sp. strain SGH1 accumulates bacterioruberin (BR), a C50 xanthophyll, as the major carotenoid. Total carotenoids in strain SGH1 amounted to nearly 400 μg BR per gram of dry biomass. Nearly 80% of total carotenoids accumulated as geometric isomers of BR: all-trans-BR (50%), 5-cis-BR (15%), 9-cis-BR (10%), 13-cis-BR (4%); other carotenoids were dehydrated derivatives of BR. Carotenogenesis in SGH1 was a reversible and salt-dependent process; transferring BR-rich cells grown in 25% (w/v) NaCl to 15% (w/v) NaCl medium resulted in depigmentation, and BR content was recovered after transference and growth of unpigmented cells to high salinity medium. Methanol extracts and purified BR isomers showed an 8-9-fold higher antioxidant activity than Trolox or β-carotene. Both, plasma membrane integrity and mitochondrial membrane potential measurements under acute 18-h assays showed that purified BR isomers were non-toxic to cultured human THP-1 cells.
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Affiliation(s)
- Nataly Flores
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Sebastián Hoyos
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Mauricio Venegas
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Alexandra Galetović
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Lidia M. Zúñiga
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Francisca Fábrega
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Bernardo Paredes
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Camila Salazar-Ardiles
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Claudia Vilo
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Carmen Ascaso
- Department Biogeochemistry and Microbial Ecology, National Museum of Natural Sciences – Spanish National Research Council, Madrid, Spain
| | - Jacek Wierzchos
- Department Biogeochemistry and Microbial Ecology, National Museum of Natural Sciences – Spanish National Research Council, Madrid, Spain
| | - Virginia Souza-Egipsy
- Department of Macromolecular Physics, Institute of Material Structure – Spanish National Research Council, Madrid, Spain
| | - Jorge E. Araya
- Laboratory of Molecular Parasitology, Department of Medical Technology and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
| | - Ramón Alberto Batista-García
- Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Benito Gómez-Silva
- Laboratory of Biochemistry, Biomedical Department and Centre for Biotechnology and Bioengineering, Universidad de Antofagasta, Antofagasta, Chile
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39
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Tait AW, Gagen EJ, Wilson SA, Tomkins AG, Southam G. Eukaryotic Colonization of Micrometer-Scale Cracks in Rocks: A "Microfluidics" Experiment Using Naturally Weathered Meteorites from the Nullarbor Plain, Australia. ASTROBIOLOGY 2020; 20:364-374. [PMID: 31873039 DOI: 10.1089/ast.2019.2077] [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: 06/10/2023]
Abstract
The advent of microfluidics has revolutionized the way we understand how microorganisms propagate through microporous spaces. Here, we apply this understanding to the study of how endolithic environmental microorganisms colonize the interiors of sterile rock. The substrates used for our study are stony meteorites from the Nullarbor Plain, Australia; a semiarid limestone karst that provides an ideal setting for preserving meteorites. Periodic flooding of the Nullarbor provides a mechanism by which microorganisms and exogenous nutrients may infiltrate meteorites. Our laboratory experiments show that environmental microorganisms reach depths greater than 400 μm by propagating through existing brecciation, passing through cracks no wider than the diameter of a resident cell (i.e., ∼5 μm). Our observations are consistent with the propagation of these eukaryotic cells via growth and cell division rather than motility. The morphology of the microorganisms changed as a result of propagation through micrometer-scale cracks, as has been observed previously for bacteria on microfluidic chips. It has been suggested that meteorites could have served as preferred habitats for microorganisms on ancient Mars. Based on our results, the depths reached by terrestrial microorganisms within meteorites would be sufficient to mitigate against the harmful effects of ionizing radiation, such as UV light, in Earth's deserts and potentially on Mars, if similar processes of microbial colonization had once been active there. Thus, meteorites landing in ancient lakes on Mars, that later dried out, could have been some of the last inhabited locations on the surface, serving as refugia before the planet's surface became inhospitable. Finally, our observations suggest that terrestrial microorganisms can colonize very fine cracks within meteorites (and potentially spaceships and rovers) on unexpectedly short timescales, with important implications for both recognition of extraterrestrial life in returned geological samples and planetary protection.
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Affiliation(s)
- Alastair W Tait
- School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia
- Biological and Environmental Sciences, University of Stirling, Stirling, United Kingdom
| | - Emma J Gagen
- School of Earth and Environmental Sciences, The University of Queensland, St. Lucia, Australia
| | - Siobhan A Wilson
- School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Canada
| | - Andrew G Tomkins
- School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia
| | - Gordon Southam
- School of Earth and Environmental Sciences, The University of Queensland, St. Lucia, Australia
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40
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Garrido-Benavent I, Pérez-Ortega S, Durán J, Ascaso C, Pointing SB, Rodríguez-Cielos R, Navarro F, de los Ríos A. Differential Colonization and Succession of Microbial Communities in Rock and Soil Substrates on a Maritime Antarctic Glacier Forefield. Front Microbiol 2020; 11:126. [PMID: 32117148 PMCID: PMC7018881 DOI: 10.3389/fmicb.2020.00126] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 01/20/2020] [Indexed: 12/20/2022] Open
Abstract
Glacier forefields provide a unique chronosequence to assess microbial or plant colonization and ecological succession on previously uncolonized substrates. Patterns of microbial succession in soils of alpine and subpolar glacier forefields are well documented but those affecting high polar systems, including moraine rocks, remain largely unexplored. In this study, we examine succession patterns in pioneering bacterial, fungal and algal communities developing on moraine rocks and soil at the Hurd Glacier forefield (Livingston Island, Antarctica). Over time, changes were produced in the microbial community structure of rocks and soils (ice-free for different lengths of time), which differed between both substrates across the entire chronosequence, especially for bacteria and fungi. In addition, fungal and bacterial communities showed more compositional consistency in soils than rocks, suggesting community assembly in each niche could be controlled by processes operating at different temporal and spatial scales. Microscopy revealed a patchy distribution of epilithic and endolithic lithobionts, and increasing endolithic colonization and microbial community complexity along the chronosequence. We conclude that, within relatively short time intervals, primary succession processes at polar latitudes involve significant and distinct changes in edaphic and lithic microbial communities associated with soil development and cryptogamic colonization.
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Affiliation(s)
- Isaac Garrido-Benavent
- Departamento de Biogeoquímica y Ecología Microbiana, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
| | | | - Jorge Durán
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Carmen Ascaso
- Departamento de Biogeoquímica y Ecología Microbiana, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
| | - Stephen B. Pointing
- Yale-NUS College, National University of Singapore, Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Ricardo Rodríguez-Cielos
- ETSI de Telecomunicación, Departamento de Señales, Sistemas y Radiocomunicaciones, Universidad Politécnica de Madrid, Madrid, Spain
| | - Francisco Navarro
- ETSI de Telecomunicación, Departamento de Matemática Aplicada a las TIC, Universidad Politécnica de Madrid, Madrid, Spain
| | - Asunción de los Ríos
- Departamento de Biogeoquímica y Ecología Microbiana, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
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41
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Qu EB, Omelon CR, Oren A, Meslier V, Cowan DA, Maggs-Kölling G, DiRuggiero J. Trophic Selective Pressures Organize the Composition of Endolithic Microbial Communities From Global Deserts. Front Microbiol 2020; 10:2952. [PMID: 31969867 PMCID: PMC6960110 DOI: 10.3389/fmicb.2019.02952] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 12/09/2019] [Indexed: 11/29/2022] Open
Abstract
Studies of microbial biogeography are often convoluted by extremely high diversity and differences in microenvironmental factors such as pH and nutrient availability. Desert endolithic (inside rock) communities are relatively simple ecosystems that can serve as a tractable model for investigating long-range biogeographic effects on microbial communities. We conducted a comprehensive survey of endolithic sandstones using high-throughput marker gene sequencing to characterize global patterns of diversity in endolithic microbial communities. We also tested a range of abiotic variables in order to investigate the factors that drive community assembly at various trophic levels. Macroclimate was found to be the primary driver of endolithic community composition, with the most striking difference witnessed between hot and polar deserts. This difference was largely attributable to the specialization of prokaryotic and eukaryotic primary producers to different climate conditions. On a regional scale, microclimate and properties of the rock substrate were found to influence community assembly, although to a lesser degree than global hot versus polar conditions. We found new evidence that the factors driving endolithic community assembly differ between trophic levels. While phototrophic taxa, mostly oxygenic photosynthesizers, were rigorously selected for among different sites, heterotrophic taxa were more cosmopolitan, suggesting that stochasticity plays a larger role in heterotroph assembly. This study is the first to uncover the global drivers of desert endolithic diversity using high-throughput sequencing. We demonstrate that phototrophs and heterotrophs in the endolithic community assemble under different stochastic and deterministic influences, emphasizing the need for studies of microorganisms in context of their functional niche in the community.
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Affiliation(s)
- Evan B. Qu
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Chris R. Omelon
- Department of Geography and Planning, Queen’s University, Kingston, ON, Canada
| | - Aharon Oren
- Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Victoria Meslier
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Don A. Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | | | - Jocelyne DiRuggiero
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
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42
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Villa F, Cappitelli F. The Ecology of Subaerial Biofilms in Dry and Inhospitable Terrestrial Environments. Microorganisms 2019; 7:microorganisms7100380. [PMID: 31547498 PMCID: PMC6843906 DOI: 10.3390/microorganisms7100380] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 09/17/2019] [Accepted: 09/20/2019] [Indexed: 11/23/2022] Open
Abstract
The ecological relationship between minerals and microorganisms arguably represents one of the most important associations in dry terrestrial environments, since it strongly influences major biochemical cycles and regulates the productivity and stability of the Earth’s food webs. Despite being inhospitable ecosystems, mineral substrata exposed to air harbor form complex and self-sustaining communities called subaerial biofilms (SABs). Using life on air-exposed minerals as a model and taking inspiration from the mechanisms of some microorganisms that have adapted to inhospitable conditions, we illustrate the ecology of SABs inhabiting natural and built environments. Finally, we advocate the need for the convergence between the experimental and theoretical approaches that might be used to characterize and simulate the development of SABs on mineral substrates and SABs’ broader impacts on the dry terrestrial environment.
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Affiliation(s)
- Federica Villa
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy.
| | - Francesca Cappitelli
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy.
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43
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Louati M, Ennis NJ, Ghodhbane-Gtari F, Hezbri K, Sevigny JL, Fahnestock MF, Cherif-Silini H, Bryce JG, Tisa LS, Gtari M. Elucidating the ecological networks in stone-dwelling microbiomes. Environ Microbiol 2019; 22:1467-1480. [PMID: 31158316 DOI: 10.1111/1462-2920.14700] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/29/2019] [Accepted: 05/31/2019] [Indexed: 11/30/2022]
Abstract
Stone surfaces are extreme environments that support microbial life. This microbial growth occurs despite unfavourable conditions associated with stone including limited sources of nutrients and water, high pH and exposure to extreme variations in temperature, humidity and irradiation. These stone-dwelling microbes are often resistant to extreme environments including exposure to desiccation, heavy metals, UV and Gamma irradiation. Here, we report on the effects of climate and stone geochemistry on microbiomes of Roman stone ruins in North Africa. Stone microbiomes were dominated by Actinobacteria, Cyanobacteria and Proteobacteria but were heavily impacted by climate variables that influenced water availability. Stone geochemistry also influenced community diversity, particularly through biologically available P, Mn and Zn. Functions associated with photosynthesis and UV protection were enriched in the metagenomes, indicating the significance of these functions for community survival on stones. Core members of the stone microbial communities were also identified and included Geodermatophilaceae, Rubrobacter, Sphingomonas and others. Our research has helped to expand the understanding of stone microbial community structure and functional capacity within the context of varying climates, geochemical properties and stone conditions.
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Affiliation(s)
- Moussa Louati
- Institut National des Sciences Appliquées et de Technologie, Université Carthage, Centre Urbain Nord, BP 676-1080, Tunis Cedex, Tunisia
| | - Nathaniel J Ennis
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA
| | - Faten Ghodhbane-Gtari
- Institut National des Sciences Appliquées et de Technologie, Université Carthage, Centre Urbain Nord, BP 676-1080, Tunis Cedex, Tunisia.,Laboratoire Microorganismeset Biomolécules Actives (LR03ES03), Faculté des Sciences de Tunis, Université Tunis El Manar, 2092, Tunis, Tunisia
| | - Karima Hezbri
- Institut National des Sciences Appliquées et de Technologie, Université Carthage, Centre Urbain Nord, BP 676-1080, Tunis Cedex, Tunisia
| | - Joseph L Sevigny
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA.,Hubbard Center for Genome Studies, University of New Hampshire, Durham, NH, USA
| | - Maria F Fahnestock
- Department of Earth Sciences, University of New Hampshire, Durham, NH, USA
| | - Hafsa Cherif-Silini
- Laboratory of Applied Microbiology, Department of Microbiology, Faculty of Natural and Life Sciences, Ferhat Abbas University, 19000, Setif, Algeria
| | - Julia G Bryce
- Department of Earth Sciences, University of New Hampshire, Durham, NH, USA
| | - Louis S Tisa
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH, USA.,Hubbard Center for Genome Studies, University of New Hampshire, Durham, NH, USA
| | - Maher Gtari
- Institut National des Sciences Appliquées et de Technologie, Université Carthage, Centre Urbain Nord, BP 676-1080, Tunis Cedex, Tunisia
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44
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Rego A, Raio F, Martins TP, Ribeiro H, Sousa AGG, Séneca J, Baptista MS, Lee CK, Cary SC, Ramos V, Carvalho MF, Leão PN, Magalhães C. Actinobacteria and Cyanobacteria Diversity in Terrestrial Antarctic Microenvironments Evaluated by Culture-Dependent and Independent Methods. Front Microbiol 2019; 10:1018. [PMID: 31214128 PMCID: PMC6555387 DOI: 10.3389/fmicb.2019.01018] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 04/24/2019] [Indexed: 12/13/2022] Open
Abstract
Bacterial diversity from McMurdo Dry Valleys in Antarctica, the coldest desert on earth, has become more easily assessed with the development of High Throughput Sequencing (HTS) techniques. However, some of the diversity remains inaccessible by the power of sequencing. In this study, we combine cultivation and HTS techniques to survey actinobacteria and cyanobacteria diversity along different soil and endolithic micro-environments of Victoria Valley in McMurdo Dry Valleys. Our results demonstrate that the Dry Valleys actinobacteria and cyanobacteria distribution is driven by environmental forces, in particular the effect of water availability and endolithic environments clearly conditioned the distribution of those communities. Data derived from HTS show that the percentage of cyanobacteria decreases from about 20% in the sample closest to the water source to negligible values on the last three samples of the transect with less water availability. Inversely, actinobacteria relative abundance increases from about 20% in wet soils to over 50% in the driest samples. Over 30% of the total HTS data set was composed of actinobacterial strains, mainly distributed by 5 families: Sporichthyaceae, Euzebyaceae, Patulibacteraceae, Nocardioidaceae, and Rubrobacteraceae. However, the 11 actinobacterial strains isolated in this study, belonged to Micrococcaceae and Dermacoccaceae families that were underrepresented in the HTS data set. A total of 10 cyanobacterial strains from the order Synechococcales were also isolated, distributed by 4 different genera (Nodosilinea, Leptolyngbya, Pectolyngbya, and Acaryochloris-like). In agreement with the cultivation results, Leptolyngbya was identified as dominant genus in the HTS data set. Acaryochloris-like cyanobacteria were found exclusively in the endolithic sample and represented 44% of the total 16S rRNA sequences, although despite our efforts we were not able to properly isolate any strain from this Acaryochloris-related group. The importance of combining cultivation and sequencing techniques is highlighted, as we have shown that culture-dependent methods employed in this study were able to retrieve actinobacteria and cyanobacteria taxa that were not detected in HTS data set, suggesting that the combination of both strategies can be usefull to recover both abundant and rare members of the communities.
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Affiliation(s)
- Adriana Rego
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal.,Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Francisco Raio
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
| | - Teresa P Martins
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
| | - Hugo Ribeiro
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal.,Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - António G G Sousa
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
| | - Joana Séneca
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
| | - Mafalda S Baptista
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal.,International Centre for Terrestrial Antarctic Research, University of Waikato, Hamilton, New Zealand
| | - Charles K Lee
- International Centre for Terrestrial Antarctic Research, University of Waikato, Hamilton, New Zealand.,School of Science, University of Waikato, Hamilton, New Zealand
| | - S Craig Cary
- International Centre for Terrestrial Antarctic Research, University of Waikato, Hamilton, New Zealand.,School of Science, University of Waikato, Hamilton, New Zealand
| | - Vitor Ramos
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
| | - Maria F Carvalho
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
| | - Pedro N Leão
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
| | - Catarina Magalhães
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal.,Faculty of Sciences, University of Porto, Porto, Portugal
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Kaur S, Kurtz HD. Core bacterial community composition of a cryptoendolithic ecosystem in the Grand Staircase-Escalante National Monument, Utah. Microbiologyopen 2019; 8:e00707. [PMID: 30079546 PMCID: PMC6528646 DOI: 10.1002/mbo3.707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 06/12/2018] [Accepted: 07/04/2018] [Indexed: 11/21/2022] Open
Abstract
Cryptoendolithic bacterial communities in the Jurassic Navajo Sandstones play an important ecological role in this ecosystem. Developing a better understanding of the role of these cryptoendolithic communities required a deeper knowledge of the microbial diversity present. We analyzed the bacterial diversity in eight sandstones samples from several microgeological features associated with a large sandstone dome. Cryptoendolithic bacterial diversity is clustered into three distinct groups which correlated with topography, suggesting the duration of water retention might be a factor. Comparisons of diversity between each cluster showed that a core bacterial community exists in this habitat. The overall bacterial community structure was dominated by Cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria. The most prevalent genera in cyanobacteria were Leptolyngbya, Chroococcidiopsis, and unclassified cyanobacteria accounting for the bulk of cyanobacterial sequences. Within the Proteobacteria, Alphaproteobacteria were the largest class detected, with members of the Acetobacteraceae, particularly the genus Acidiphilium, being the most abundant. Acidiphilium spp. are capable of aerobic ferric iron reduction under moderately acidic conditions, explaining the high levels of iron (II) in this system. This study highlights the extent of unexplored bacterial diversity in this habitat system and sets the premise for elaborating on the ecological function of cryptoendolithic communities.
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Affiliation(s)
- Sukhpreet Kaur
- Department of Biological SciencesClemson UniversityClemsonSouth Carolina
| | - HD Kurtz
- Department of Biological SciencesClemson UniversityClemsonSouth Carolina
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Knabe N, Gorbushina AA. Territories of Rock-Inhabiting Fungi: Survival on and Alteration of Solid Air-Exposed Surfaces. J Microbiol Methods 2018. [DOI: 10.1016/bs.mim.2018.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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