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Makk J, Németh ÁC, Tóth E, Németh P, Kovács I, Demény A, Sipos G, Borsodi AK, Lange-Enyedi NT. Actively forming microbial mats provide insight into the development of microdigitate stromatolites. Sci Rep 2025; 15:5497. [PMID: 39953250 PMCID: PMC11829031 DOI: 10.1038/s41598-025-90175-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2024] [Accepted: 02/11/2025] [Indexed: 02/17/2025] Open
Abstract
Stromatolites can be traced back to ∼3.5 billion years. They were widespread in the shorelines of ancient oceans and seas. However, they are uncommon nowadays, and basic information is lacking about how these unique carbonate structures developed. Here we study the unusually thick (3-5 cm) biofilms of the 79.2 °C outflow from Köröm thermal well (Hungary) and demonstrate that its microbial mat - carbonate architecture is similar to fossilized microdigitate stromatolites. Our observations reveal vertically oriented fibrous mineral fabrics, typical of stromatolites, in the red biofilm and clotted mesostructures, typical of thrombolites, in the green biofilm. These layers contain carbonate peloids and show network structures, formed by filamentous microbes. The 16S rRNA gene-based amplicon sequencing implies that numerous undescribed taxa may contribute to the carbonate mineralisation. The biofilms abundantly contain the phyla Bacteroidota, Pseudomonadota and Cyanobacteria. Geitlerinema PCC-8501 and Raineya are characteristic for the green biofilm, whereas uncultured Oxyphotobacteria, unc. Saprospiraceae and unc. Cytophagales are abundant in the red biofilm. A hydrogen-oxidizing Hydrogenobacter within the phylum Aquificota and unclassified Bacteria together with the phylum Deinococcota dominate the water and carbonate samples. The morphological structure and taxonomic composition of Köröm biofilm is a unique representation of the development processes of microbialite formations.
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Affiliation(s)
- Judit Makk
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary.
| | - Ábel Csongor Németh
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
- Department of Public Health Laboratories, National Public Health and Pharmaceutical Center, Albert Flórián Street 2-6, 1097, Budapest, Hungary
- Doctoral School of Environmental Sciences, ELTE Eötvös Loránd University, Pázmány Péter Street 2, 1117, Budapest, Hungary
| | - Erika Tóth
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
| | - Péter Németh
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi Út 45, 1112, Budapest, Hungary
- Research Institute of Biomolecular and Chemical Engineering, Nanolab, University of Pannonia, Egyetem Út 10, 8200, Veszprém, Hungary
| | - Ivett Kovács
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi Út 45, 1112, Budapest, Hungary
| | - Attila Demény
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi Út 45, 1112, Budapest, Hungary
| | - György Sipos
- Functional Genomics and Bioinformatics Group, Faculty of Forestry, University of Sopron, Bajcsy-Zsilinszky Út 4, 9400, Sopron, Hungary
| | - Andrea K Borsodi
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
- Institute of Aquatic Ecology, HUN-REN Centre for Ecological Research, Karolina Út 29, 1113, Budapest, Hungary
| | - Nóra Tünde Lange-Enyedi
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. Sétány 1/C, 1117, Budapest, Hungary
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi Út 45, 1112, Budapest, Hungary
- Functional Genomics and Bioinformatics Group, Faculty of Forestry, University of Sopron, Bajcsy-Zsilinszky Út 4, 9400, Sopron, Hungary
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Borsodi AK. Taxonomic diversity of extremophilic prokaryotes adapted to special environmental parameters in Hungary: a review. Biol Futur 2024; 75:183-192. [PMID: 38753295 DOI: 10.1007/s42977-024-00224-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 04/26/2024] [Indexed: 06/18/2024]
Abstract
The taxonomic and metabolic diversity of prokaryotes and their adaptability to extreme environmental parameters have allowed extremophiles to find their optimal living conditions under extreme conditions for one or more environmental parameters. Natural habitats abundant in extremophilic microorganisms are relatively rare in Hungary. Nevertheless, alkaliphiles and halophiles can flourish in shallow alkaline lakes (soda pans) and saline (solonetz) soils, where extreme weather conditions favor the development of unique bacterial communities. In addition, the hot springs and thermal wells that supply spas and thermal baths and provide water for energy use are suitable colonization sites for thermophiles and hyperthermophiles. Polyextremophiles, adapted to multiple extreme circumstances, can be found in the aphotic, nutrient-poor and radioactive hypogenic caves of the Buda Thermal Karst, among others. The present article reviews the organization, taxonomic composition, and potential role of different extremophilic bacterial communities in local biogeochemical cycles, based on the most recent studies on extremophiles in Hungary.
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Affiliation(s)
- Andrea K Borsodi
- Department of Microbiology, Institute of Biology, ELTE, Eötvös Loránd University, Pázmány Péter sétány 1/C, Budapest, 1117, Hungary.
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Lange-Enyedi NT, Borsodi AK, Németh P, Czuppon G, Kovács I, Leél-Őssy S, Dobosy P, Felföldi T, Demény A, Makk J. Habitat-related variability in the morphological and taxonomic diversity of microbial communities in two Hungarian epigenic karst caves. FEMS Microbiol Ecol 2023; 99:fiad161. [PMID: 38066687 DOI: 10.1093/femsec/fiad161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 10/13/2023] [Accepted: 12/07/2023] [Indexed: 12/27/2023] Open
Abstract
The physical and chemical characteristics of the bedrock, along with the geological and hydrological conditions of karst caves may influence the taxonomic and functional diversity of prokaryotes. Most studies so far have focused on microbial communities of caves including only a few samples and have ignored the chemical heterogeneity of different habitat types such as sampling sites, dripping water, carbonate precipitates, cave walls, cave sediment and surface soils connected to the caves. The aim of the present study was to compare the morphology, the composition and physiology of the microbiota in caves with similar environmental parameters (temperature, host rock, elemental and mineral composition of speleothems) but located in different epigenic karst systems. Csodabogyós Cave and Baradla Cave (Hungary) were selected for the analysis of bacterial and archaeal communities using electron microscopy, amplicon sequencing, X-ray diffraction, and mass spectroscopic techniques. The microbial communities belonged to the phyla Pseudomonadota, Acidobacteriota, Nitrospirota and Nitrososphaerota, and they showed site-specific variation in composition and diversity. The results indicate that morphological and physiological adaptations provide survival for microorganisms according to the environment. In epigenic karst caves, prokaryotes are prone to increase their adsorption surface, cooperate in biofilms, and implement chemolithoautotrophic growth with different electron-donors and acceptors available in the microhabitats.
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Affiliation(s)
- Nóra Tünde Lange-Enyedi
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi út 45, H-1112 Budapest, Hungary
- Department of Microbiology, Institute of Biology, Faculty of Science, Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117 Budapest, Hungary
| | - Andrea K Borsodi
- Department of Microbiology, Institute of Biology, Faculty of Science, Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117 Budapest, Hungary
- Institute of Aquatic Ecology, HUN-REN Centre for Ecological Research, Karolina út 29, H-1113 Budapest, Hungary
| | - Péter Németh
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi út 45, H-1112 Budapest, Hungary
- Research Institute of Biomolecular and Chemical Engineering, Nanolab, University of Pannonia, Egyetem út 10, H-8200 Veszprém, Hungary
| | - György Czuppon
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi út 45, H-1112 Budapest, Hungary
| | - Ivett Kovács
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi út 45, H-1112 Budapest, Hungary
| | - Szabolcs Leél-Őssy
- Department of Physical and Applied Geology, Faculty of Science, Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117 Budapest, Hungary
| | - Péter Dobosy
- Institute of Aquatic Ecology, HUN-REN Centre for Ecological Research, Karolina út 29, H-1113 Budapest, Hungary
| | - Tamás Felföldi
- Department of Microbiology, Institute of Biology, Faculty of Science, Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117 Budapest, Hungary
- Institute of Aquatic Ecology, HUN-REN Centre for Ecological Research, Karolina út 29, H-1113 Budapest, Hungary
| | - Attila Demény
- Institute for Geological and Geochemical Research, HUN-REN Research Centre for Astronomy and Earth Sciences, Budaörsi út 45, H-1112 Budapest, Hungary
| | - Judit Makk
- Department of Microbiology, Institute of Biology, Faculty of Science, Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117 Budapest, Hungary
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Prokaryotic and eukaryotic diversity in hydrothermal continental systems. Arch Microbiol 2021; 203:3751-3766. [PMID: 34143270 DOI: 10.1007/s00203-021-02416-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 05/28/2021] [Accepted: 05/31/2021] [Indexed: 02/07/2023]
Abstract
The term extremophile was suggested more than 30 years ago and represents microorganisms that are capable of developing and living under extreme conditions, these conditions being particularly hostile to other types of microorganisms and to humankind. In terrestrial hydrothermal sites, like hot springs, "mud pools", solfataras, and geysers, the dominant extreme conditions are high temperature, low or high pH, and high levels of salinity. The diversity of microorganisms inhabiting these sites is determined by the conditions of the environment. Organisms belonging to the domains Archaea and Bacteria are more represented than the one belonging to Eukarya. Eukarya members tend to be less present because of their lower tolerance to higher temperatures, however, they perform important ecosystem processes when present. Both prokaryotes and eukaryotes have morphological and physical adaptations that allow them to colonize extreme environments. Microbial mats are complex associations of microorganisms that help the colonization of more extreme systems. In this review, a characterization of prokaryotic and eukaryotic organisms that populate terrestrial hydrothermal systems are made.
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Anda D, Szabó A, Kovács-Bodor P, Makk J, Felföldi T, Ács É, Mádl-Szőnyi J, Borsodi AK. In situ modelling of biofilm formation in a hydrothermal spring cave. Sci Rep 2020; 10:21733. [PMID: 33303927 PMCID: PMC7729855 DOI: 10.1038/s41598-020-78759-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 11/24/2020] [Indexed: 12/29/2022] Open
Abstract
Attachment of microorganisms to natural or artificial surfaces and the development of biofilms are complex processes which can be influenced by several factors. Nevertheless, our knowledge on biofilm formation in karstic environment is quite incomplete. The present study aimed to examine biofilm development for a year under controlled conditions in quasi-stagnant water of a hydrothermal spring cave located in the Buda Thermal Karst System (Hungary). Using a model system, we investigated how the structure of the biofilm is formed from the water and also how the growth rate of biofilm development takes place in this environment. Besides scanning electron microscopy, next-generation DNA sequencing was used to reveal the characteristic taxa and major shifts in the composition of the bacterial communities. Dynamic temporal changes were observed in the structure of bacterial communities. Bacterial richness and diversity increased during the biofilm formation, and 9-12 weeks were needed for the maturation. Increasing EPS production was also observed from the 9-12 weeks. The biofilm was different from the water that filled the cave pool, in terms of the taxonomic composition and metabolic potential of microorganisms. In these karstic environments, the formation of mature biofilm appears to take place relatively quickly, in a few months.
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Affiliation(s)
- Dóra Anda
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary.
| | - Attila Szabó
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary
| | - Petra Kovács-Bodor
- Department of Geology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary
| | - Judit Makk
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary
| | - Tamás Felföldi
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary
| | - Éva Ács
- Danube Research Institute, Centre for Ecological Research, Karolina út 29, Budapest, 1113, Hungary.,Faculty of Water Sciences, National University of Public Service, Bajcsy-Zsilinszky utca, 12-14, 6500, Baja, Hungary
| | - Judit Mádl-Szőnyi
- Department of Geology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary
| | - Andrea K Borsodi
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary. .,Danube Research Institute, Centre for Ecological Research, Karolina út 29, Budapest, 1113, Hungary.
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Enyedi NT, Anda D, Borsodi AK, Szabó A, Pál SE, Óvári M, Márialigeti K, Kovács-Bodor P, Mádl-Szőnyi J, Makk J. Radioactive environment adapted bacterial communities constituting the biofilms of hydrothermal spring caves (Budapest, Hungary). JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 203:8-17. [PMID: 30844681 DOI: 10.1016/j.jenvrad.2019.02.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 02/12/2019] [Accepted: 02/19/2019] [Indexed: 06/09/2023]
Abstract
The thermal waters of Gellért Hill discharge area of the Buda Thermal Karst System (Hungary) are characterized by high (up to 1000 Bq/L) 222Rn-activity due to the radium-accumulating biogeochemical layers. Samples were taken from these ferruginous and calcareous layers developed on spring cave walls and water surface. Accumulation of potentially toxic metals (e.g. As, Hg, Pb, Sn, Sr, Zn) in the dense extracellular polymeric substance containing bacterial cells and remains was detected by inductively coupled plasma mass spectrometry. The comparison of bacterial phylogenetic diversity of the biofilm samples was performed by high throughput next generation sequencing (NGS). The analysis showed similar sets of mainly unidentified taxa of phyla Chloroflexi, Nitrospirae, Proteobacteria, Planctomycetes; however, large differences were found in their abundance. Cultivation-based method complemented with irradiation assay was performed using 5, 10 and 15 kGy doses of gamma-rays from a 60Co-source to reveal the extreme radiation-resistant bacteria. The phyla Actinobacteria, Firmicutes, Proteobacteria (classes Alpha- Beta- and Gammaproteobacteria), Bacteriodetes and Deinococcus-Thermus were represented among the 452 bacterial strains. The applied irradiation treatments promoted the isolation of 100 different species, involving candidate novel species, as well. The vast majority of the isolates belonged to bacterial taxa previously unknown as radiation-resistant microorganisms. Members of the genera Paracoccus, Marmoricola, Dermacoccus and Kytococcus were identified from the 15 kGy dose irradiated samples. The close relatives of several known radiation-tolerant bacteria were also detected from the biofilm samples, alongside with bacteria capable of detoxification by metal accumulation, adsorption and precipitation in the form of calcium-carbonate which possibly maintain the viability of the habitat. The results suggest the establishment of a unique, extremophilic microbiota in the studied hydrothermal spring caves.
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Affiliation(s)
- Nóra Tünde Enyedi
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary.
| | - Dóra Anda
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary; Danube Research Institute, MTA Centre for Ecological Research, Karolina út 29, H-1113, Budapest, Hungary.
| | - Andrea K Borsodi
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary; Danube Research Institute, MTA Centre for Ecological Research, Karolina út 29, H-1113, Budapest, Hungary.
| | - Attila Szabó
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary.
| | - Sára Eszter Pál
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary.
| | - Mihály Óvári
- Danube Research Institute, MTA Centre for Ecological Research, Karolina út 29, H-1113, Budapest, Hungary; Department of Analytical Chemistry, ELTE Eötvös Loránd University, Pázmány P. sétány 1/A, H-1117, Budapest, Hungary.
| | - Károly Márialigeti
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary.
| | - Petra Kovács-Bodor
- Department of Physical and Applied Geology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary.
| | - Judit Mádl-Szőnyi
- Department of Physical and Applied Geology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary.
| | - Judit Makk
- Department of Microbiology, ELTE Eötvös Loránd University, Pázmány P. sétány 1/C, H-1117, Budapest, Hungary.
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Borsodi AK, Anda D, Makk J, Krett G, Dobosy P, Büki G, Erőss A, Mádl-Szőnyi J. Biofilm forming bacteria and archaea in thermal karst springs of Gellért Hill discharge area (Hungary). J Basic Microbiol 2018; 58:928-937. [PMID: 30160784 DOI: 10.1002/jobm.201800138] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/13/2018] [Accepted: 06/24/2018] [Indexed: 12/20/2022]
Abstract
The Buda Thermal Karst System (BTKS) is an extensive active hypogenic cave system located beneath the residential area of the Hungarian capital. At the river Danube, several thermal springs discharge forming spring caves. To reveal and compare the morphological structure and prokaryotic diversity of reddish-brown biofilms developed on the carbonate rock surfaces of the springs, scanning electron microscopy (SEM), and molecular cloning were applied. Microbial networks formed by filamentous bacteria and other cells with mineral crystals embedded in extracellular polymeric substances were observed in the SEM images. Biofilms were dominated by prokaryotes belonging to phyla Proteobacteria, Chloroflexi and Nitrospirae (Bacteria) and Thaumarchaeota (Archaea) but their abundance showed differences according to the type of the host rock, geographic distance, and different water exchange. In addition, representatives of phyla Acidobacteria, Actinobacteria, Caldithrix, Cyanobacteria, Firmicutes Gemmatimonadetes, and several candidate divisions of Bacteria as well as Crenarchaeota and Euryarchaeota were detected in sample-dependent higher abundance. The results indicate that thermophilic, anaerobic sulfur-, sulfate-, nitrate-, and iron(III)-reducing chemoorganotrophic as well as sulfur-, ammonia-, and nitrite-oxidizing chemolithotrophic prokaryotes can interact in the studied biofilms adapted to the unique and extreme circumstances (e.g., aphotic and nearly anoxic conditions, oligotrophy, and radionuclide accumulation) in the thermal karst springs.
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Affiliation(s)
- Andrea K Borsodi
- Department of Microbiology, ELTE Eötvös Loránd University, Budapest, Hungary.,Danube Research Institute, MTA Centre for Ecological Research, Budapest, Hungary
| | - Dóra Anda
- Department of Microbiology, ELTE Eötvös Loránd University, Budapest, Hungary.,Danube Research Institute, MTA Centre for Ecological Research, Budapest, Hungary
| | - Judit Makk
- Department of Microbiology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Gergely Krett
- Department of Microbiology, ELTE Eötvös Loránd University, Budapest, Hungary.,Danube Research Institute, MTA Centre for Ecological Research, Budapest, Hungary
| | - Péter Dobosy
- Danube Research Institute, MTA Centre for Ecological Research, Budapest, Hungary
| | - Gabriella Büki
- Department of Microbiology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Anita Erőss
- Department of Physical and Applied Geology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Judit Mádl-Szőnyi
- Department of Physical and Applied Geology, ELTE Eötvös Loránd University, Budapest, Hungary
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Selvarajan R, Sibanda T, Tekere M. Thermophilic bacterial communities inhabiting the microbial mats of "indifferent" and chalybeate (iron-rich) thermal springs: Diversity and biotechnological analysis. Microbiologyopen 2018; 7:e00560. [PMID: 29243409 PMCID: PMC5911995 DOI: 10.1002/mbo3.560] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 10/13/2017] [Accepted: 10/24/2017] [Indexed: 11/08/2022] Open
Abstract
Microbial mats are occasionally reported in thermal springs and information on such mats is very scarce. In this study, microbial mats were collected from two hot springs (Brandvlei (BV) and Calitzdorp (CA)), South Africa and subjected to scanning electron microscopy (SEM) and targeted 16S rRNA gene amplicon analysis using Next Generation Sequencing (NGS). Spring water temperature was 55°C for Brandvlei and 58°C for Calitzdorp while the pH of both springs was slightly acidic, with an almost identical pH range (6.2-6.3). NGS analysis resulted in a total of 4943 reads, 517 and 736 OTUs for BV and CA at, respectively, a combined total of 14 different phyla in both samples, 88 genera in CA compared to 45 in BV and 37.64% unclassified sequences in CA compared to 27.32% recorded in BV. Dominant bacterial genera in CA microbial mat were Proteobacteria (29.19%), Bacteroidetes (9.41%), Firmicutes (9.01%), Cyanobacteria (6.89%), Actinobacteria (2.65%), Deinococcus-Thermus (2.57%), and Planctomycetes (1.94%) while the BV microbial mat was dominated by Bacteroidetes (47.3%), Deinococcus-Thermus (12.35%), Proteobacteria (7.98%), and Planctomycetes (2.97%). Scanning electron microscopy results showed the presence of microbial filaments possibly resembling cyanobacteria, coccids, rod-shaped bacteria and diatoms in both microbial mats. Dominant genera that were detected in this study have been linked to different biotechnological applications including hydrocarbon degradation, glycerol fermentation, anoxic-fermentation, dehalogenation, and biomining processes. Overall, the results of this study exhibited thermophilic bacterial community structures with high diversity in microbial mats, which have a potential for biotechnological exploitation.
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Affiliation(s)
- Ramganesh Selvarajan
- Department of Environmental SciencesCollege of Agriculture and Environmental SciencesUNISA Science CampusFloridaSouth Africa
| | - Timothy Sibanda
- Department of Environmental SciencesCollege of Agriculture and Environmental SciencesUNISA Science CampusFloridaSouth Africa
| | - Memory Tekere
- Department of Environmental SciencesCollege of Agriculture and Environmental SciencesUNISA Science CampusFloridaSouth Africa
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Investigation of bacterial and archaeal communities: novel protocols using modern sequencing by Illumina MiSeq and traditional DGGE-cloning. Extremophiles 2016; 20:795-808. [DOI: 10.1007/s00792-016-0855-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 06/14/2016] [Indexed: 01/23/2023]
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