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Gorlenko V, Savvichev A, Kadnikov V, Rusanov I, Beletsky A, Zakharova E, Kostrikina N, Sigalevich P, Veslopolova E, Pimenov N. A Novel View of the Diversity of Anoxygenic Phototrophic Bacteria Inhabiting the Chemocline of Meromictic Karst Lakes. Microorganisms 2023; 12:13. [PMID: 38276182 PMCID: PMC10820006 DOI: 10.3390/microorganisms12010013] [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: 11/10/2023] [Revised: 12/07/2023] [Accepted: 12/12/2023] [Indexed: 01/27/2024] Open
Abstract
The rates of oxygenic and anoxygenic photosynthesis, the microorganisms responsible for these processes, and the hydrochemical characteristics of the sulfide-containing karst lakes, Black Kichier and Big Kichier (Mari El Republic), were investigated. In these lakes, a plate of anoxygenic phototrophic bacteria (APB) is formed at the upper boundary of sulfide occurrence in the water. The phototrophic community of the chemocline zone was analyzed using a combination of high-throughput sequencing of the 16S rRNA gene fragments and light and electron microscopic techniques. Green-colored Chlorobium clathratiforme were absolutely predominant in both lakes. The minor components included green sulfur bacteria (GSB) Chlorobium spp., symbiotic consortia Chlorochromatium magnum and Pelochromatium roseum, purple sulfur bacteria (PSB) Chromatium okenii, and unidentified phylotypes of the family Chromatiaceae, as well as members of the Chloroflexota: Chloronema sp. and Oscillochloris sp. Based on the results of the molecular analysis, the taxonomic status of Ancalochloris perfilievii and other prosthecate GSB, as well as of the PSB Thiopedia rosea, which were visually revealed in the studied freshwater lakes, is discussed.
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Affiliation(s)
- Vladimir Gorlenko
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
| | - Alexander Savvichev
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
| | - Vitaly Kadnikov
- K.G. Skryabin Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia;
| | - Igor Rusanov
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
| | - Alexey Beletsky
- K.G. Skryabin Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia;
| | - Elena Zakharova
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
| | - Nadezhda Kostrikina
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
| | - Pavel Sigalevich
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
| | - Elena Veslopolova
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
| | - Nikolay Pimenov
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia; (V.G.); (A.S.); (I.R.); (E.Z.); (N.K.); (P.S.); (E.V.); (N.P.)
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Di Nezio F, Roman S, Buetti-Dinh A, Sepúlveda Steiner O, Bouffard D, Sengupta A, Storelli N. Motile bacteria leverage bioconvection for eco-physiological benefits in a natural aquatic environment. Front Microbiol 2023; 14:1253009. [PMID: 38163082 PMCID: PMC10756677 DOI: 10.3389/fmicb.2023.1253009] [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: 07/04/2023] [Accepted: 11/23/2023] [Indexed: 01/03/2024] Open
Abstract
Introduction Bioconvection, a phenomenon characterized by the collective upward swimming of motile microorganisms, has mainly been investigated within controlled laboratory settings, leaving a knowledge gap regarding its ecological implications in natural aquatic environments. This study aims to address this question by investigating the influence of bioconvection on the eco-physiology of the anoxygenic phototrophic sulfur bacteria community of meromictic Lake Cadagno. Methods Here we comprehensively explore its effects by comparing the physicochemical profiles of the water column and the physiological traits of the main populations of the bacterial layer (BL). The search for eco-physiological effects of bioconvection involved a comparative analysis between two time points during the warm season, one featuring bioconvection (July) and the other without it (September). Results A prominent distinction in the physicochemical profiles of the water column centers on light availability, which is significantly higher in July. This minimum threshold of light intensity is essential for sustaining the physiological CO2 fixation activity of Chromatium okenii, the microorganism responsible for bioconvection. Furthermore, the turbulence generated by bioconvection redistributes sulfides to the upper region of the BL and displaces other microorganisms from their optimal ecological niches. Conclusion The findings underscore the influence of bioconvection on the physiology of C. okenii and demonstrate its functional role in improving its metabolic advantage over coexisting phototrophic sulfur bacteria. However, additional research is necessary to confirm these results and to unravel the multiscale processes activated by C. okenii's motility mechanisms.
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Affiliation(s)
- Francesco Di Nezio
- Department of Environment, Constructions, and Design, Institute of Microbiology, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Mendrisio, Switzerland
- Department of Plant Sciences, University of Geneva, Geneva, Switzerland
| | - Samuele Roman
- Department of Environment, Constructions, and Design, Institute of Microbiology, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Mendrisio, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
| | - Antoine Buetti-Dinh
- Department of Environment, Constructions, and Design, Institute of Microbiology, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Mendrisio, Switzerland
| | - Oscar Sepúlveda Steiner
- Department of Surface Waters – Research and Management, Swiss Federal Institute of Aquatic Science and Technology (Eawag), Kastanienbaum, Switzerland
- Civil and Environmental Engineering, University of California, Davis, Davis, CA, United States
| | - Damien Bouffard
- Department of Surface Waters – Research and Management, Swiss Federal Institute of Aquatic Science and Technology (Eawag), Kastanienbaum, Switzerland
- Faculty of Geosciences and Environment, Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, Switzerland
| | - Anupam Sengupta
- Department of Physics and Materials Science, Physics of Living Matter Group, Luxembourg City, Luxembourg
| | - Nicola Storelli
- Department of Environment, Constructions, and Design, Institute of Microbiology, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Mendrisio, Switzerland
- Department of Plant Sciences, University of Geneva, Geneva, Switzerland
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3
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Saini JS, Manni M, Hassler C, Cable RN, Duhaime MB, Zdobnov EM. Genomic insights into the coupling of a Chlorella-like microeukaryote and sulfur bacteria in the chemocline of permanently stratified Lake Cadagno. THE ISME JOURNAL 2023; 17:903-915. [PMID: 37031343 DOI: 10.1038/s41396-023-01396-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 03/14/2023] [Accepted: 03/16/2023] [Indexed: 04/10/2023]
Abstract
Meromictic Lake Cadagno is a permanently stratified system with a persistent microbial bloom within the oxic-anoxic boundary called the chemocline. The association between oxygenic and anoxygenic photosynthesis within the chemocline has been known for at least two decades. Although anoxygenic purple and green sulfur bacteria have been well studied, reports on oxygenic phytoplankton have remained sparse since their discovery in the 1920s. Nearly a century later, this study presents the first near-complete genome of a photosynthetic microbial eukaryote from the chemocline of Lake Cadagno, provisionally named Chlorella-like MAG. The 18.9 Mbp nuclear genome displays a high GC content (71.5%), and the phylogenetic placement suggests that it is a novel species of the genus Chlorella of Chlorophytes. Functional annotation of the Chlorella-like metagenome-assembled genome predicted 10,732 protein-coding genes, with an approximate 0.6% proportion potentially involved in carbon, sulfur, and nitrogen (C, N, and S) metabolism. In addition to C4 photosynthesis, this study detected genes for heat shock proteins (HSPs) in the Chlorella-like algae, consistent with the other Chlorella species. Altogether, the genomic insights in this study suggest the cooperation of photosynthetic algae with phototrophic sulfur bacteria via C, N, and S metabolism, which may aid their collective persistence in the Lake Cadagno chemocline. Furthermore, this work additionally presents the chloroplast genome of Cryptomonas-like species, which was likely to be presumed as cyanobacteria in previous studies because of the presence of phycobilisomes.
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Affiliation(s)
- Jaspreet S Saini
- Department F.-A Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, University of Geneva, Geneva, Switzerland.
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland.
- Swiss Institute of Bioinformatics, Lausanne, Switzerland.
- Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Mosè Manni
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Christel Hassler
- Department F.-A Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, University of Geneva, Geneva, Switzerland
- Institute of Earth Sciences, University of Lausanne, Lausanne, Switzerland
| | - Rachel N Cable
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
| | - Melissa B Duhaime
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
| | - Evgeny M Zdobnov
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland.
- Swiss Institute of Bioinformatics, Lausanne, Switzerland.
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Bacterial, Phytoplankton, and Viral Distributions and Their Biogeochemical Contexts in Meromictic Lake Cadagno Offer Insights into the Proterozoic Ocean Microbial Loop. mBio 2022; 13:e0005222. [PMID: 35726916 PMCID: PMC9426590 DOI: 10.1128/mbio.00052-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lake Cadagno, a permanently stratified high-alpine lake with a persistent microbial bloom in its chemocline, has long been considered a model for the low-oxygen, high-sulfide Proterozoic ocean. Although the lake has been studied for over 25 years, the absence of concerted study of the bacteria, phytoplankton, and viruses, together with primary and secondary production, has hindered a comprehensive understanding of its microbial food web. Here, the identities, abundances, and productivity of microbes were evaluated in the context of Lake Cadagno biogeochemistry. Photosynthetic pigments together with 16S rRNA gene phylogenies suggest the prominence of eukaryotic phytoplankton chloroplasts, primarily chlorophytes. Chloroplasts closely related to those of high-alpine-adapted Ankyra judayi persisted with oxygen in the mixolimnion, where photosynthetic efficiency was high, while chloroplasts of Closteriopsis-related chlorophytes peaked in the chemocline and monimolimnion. The anoxygenic phototrophic sulfur bacterium Chromatium dominated the chemocline along with Lentimicrobium, a genus of known fermenters. Secondary production peaked in the chemocline, which suggested that anoxygenic primary producers depended on heterotrophic nutrient remineralization. The virus-to-microbe ratio peaked with phytoplankton abundances in the mixolimnion and were at a minimum where Chromatium abundance was highest, trends that suggest that viruses may play a role in the modulation of primary production. Through the combined analysis of bacterial, eukaryotic, viral, and biogeochemical spatial dynamics, we provide a comprehensive synthesis of the Lake Cadagno microbial loop. This study offers a new ecological perspective on how biological and geochemical connections may have occurred in the chemocline of the Proterozoic ocean, where eukaryotic microbial life is thought to have evolved.
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Sanseverino I, Pretto P, António DC, Lahm A, Facca C, Loos R, Skejo H, Beghi A, Pandolfi F, Genoni P, Lettieri T. Metagenomics Analysis to Investigate the Microbial Communities and Their Functional Profile During Cyanobacterial Blooms in Lake Varese. MICROBIAL ECOLOGY 2022; 83:850-868. [PMID: 34766210 PMCID: PMC9016052 DOI: 10.1007/s00248-021-01914-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 10/26/2021] [Indexed: 05/09/2023]
Abstract
Toxic cyanobacterial blooms represent a natural phenomenon caused by a mass proliferation of photosynthetic prokaryotic microorganisms in water environments. Bloom events have been increasingly reported worldwide and their occurrence can pose serious threats to aquatic organisms and human health. In this study, we assessed the microbial composition, with a focus on Cyanobacteria, in Lake Varese, a eutrophic lake located in northern Italy. Water samples were collected and used for obtaining a 16S-based taxonomic profile and performing a shotgun sequencing analysis. The phyla found to exhibit the greatest relative abundance in the lake included Proteobacteria, Cyanobacteria, Actinobacteriota and Bacteroidota. In the epilimnion and at 2.5 × Secchi depth, Cyanobacteria were found to be more abundant compared to the low levels detected at greater depths. The blooms appear to be dominated mainly by the species Lyngbya robusta, and a specific functional profile was identified, suggesting that distinct metabolic processes characterized the bacterial population along the water column. Finally, analysis of the shotgun data also indicated the presence of a large and diverse phage population.
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Affiliation(s)
- Isabella Sanseverino
- European Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027, Ispra, VA, Italy
| | - Patrizia Pretto
- Biosearch Ambiente Srl, Via Tetti Gai 59, 10091, Alpignano, TO, Italy
| | - Diana Conduto António
- European Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027, Ispra, VA, Italy
| | - Armin Lahm
- Bioinformatics Project Support, P.za S.M. Liberatrice 18, 00153, Roma, Italy
| | - Chiara Facca
- Department of Environmental Science, Informatics and Statistics, University Ca' Foscari Venezia, Via Torino 155, 301702, Mestre, VE, Italy
| | - Robert Loos
- European Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027, Ispra, VA, Italy
| | - Helle Skejo
- European Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027, Ispra, VA, Italy
| | - Andrea Beghi
- ARPA, Agenzia Regionale Per La Protezione Dell'Ambiente Della Lombardia, Via Ippolito Rosellini 17, 20124, Milano, Italy
| | - Franca Pandolfi
- ARPA, Agenzia Regionale Per La Protezione Dell'Ambiente Della Lombardia, Via Ippolito Rosellini 17, 20124, Milano, Italy
| | - Pietro Genoni
- ARPA, Agenzia Regionale Per La Protezione Dell'Ambiente Della Lombardia, Via Ippolito Rosellini 17, 20124, Milano, Italy
| | - Teresa Lettieri
- European Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027, Ispra, VA, Italy.
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Wu YT, Chiang PW, Tandon K, Rogozin DY, Degermendzhy AG, Tang SL. Single-cell genomics-based analysis reveals a vital ecological role of Thiocapsa sp. LSW in the meromictic Lake Shunet, Siberia. Microb Genom 2021; 7:000712. [PMID: 34860152 PMCID: PMC8767323 DOI: 10.1099/mgen.0.000712] [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: 01/18/2023] Open
Abstract
Meromictic lakes usually harbour certain prevailing anoxygenic phototrophic bacteria in their anoxic zone, such as the purple sulfur bacterium (PSB) Thiocapsa sp. LSW (hereafter LSW) in Lake Shunet, Siberia. PSBs have been suggested to play a vital role in carbon, nitrogen and sulfur cycling at the oxic-anoxic interface of stratified lakes; however, the ecological significance of PSBs in the lake remains poorly understood. In this study, we explored the potential ecological role of LSW using a deep-sequencing analysis of single-cell genomics associated with flow cytometry. An approximately 2.7 Mb draft genome was obtained based on the co-assembly of five single-cell genomes. LSW might grow photolithoautotrophically and could play putative roles not only as a carbon fixer and diazotroph, but also as a sulfate reducer/oxidizer in the lake. This study provides insights into the potential ecological role of Thiocapsa sp. in meromictic lakes.
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Affiliation(s)
- Yu-Ting Wu
- Department of Forestry, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan, ROC
| | - Pei-Wen Chiang
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan, ROC
| | - Kshitij Tandon
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan, ROC
| | - Denis Yu Rogozin
- Institute of Biophysics, Siberian Division of the Russian Academy of Sciences, Krasnoyarsk, Russia,Siberian Federal University, Krasnoyarsk, Russia
| | - Andrey G. Degermendzhy
- Institute of Biophysics, Siberian Division of the Russian Academy of Sciences, Krasnoyarsk, Russia
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan, ROC,*Correspondence: Sen-Lin Tang,
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Block KR, O'Brien JM, Edwards WJ, Marnocha CL. Vertical structure of the bacterial diversity in meromictic Fayetteville Green Lake. Microbiologyopen 2021; 10:e1228. [PMID: 34459548 PMCID: PMC8330806 DOI: 10.1002/mbo3.1228] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 11/08/2022] Open
Abstract
The permanently stratified water columns in euxinic meromictic lakes produce niche environments for phototrophic sulfur oxidizers and diverse sulfur metabolisms. While Green Lake (Fayetteville, New York, NY) is known to host a diverse community of ecologically important sulfur bacteria, analyses of its microbial communities, to date, have been largely based on pigment analysis and smaller datasets from Sanger sequencing techniques. Here, we present the results of next-generation sequencing of the eubacterial community in the context of the water column geochemistry. We observed abundant purple and green sulfur bacteria, as well as anoxygenic photosynthesis-capable cyanobacteria within the upper monimolimnion. Amidst the phototrophs, we found other sulfur-cycling bacteria including sulfur disproportionators and chemotrophic sulfur oxidizers, further detailing our understanding of the sulfur cycle and microbial ecology of euxinic, meromictic lakes.
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Affiliation(s)
| | - Joy M. O'Brien
- Department of BiologyNiagara UniversityLewistonNew YorkUSA
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Exploring Viral Diversity in a Gypsum Karst Lake Ecosystem Using Targeted Single-Cell Genomics. Genes (Basel) 2021; 12:genes12060886. [PMID: 34201311 PMCID: PMC8226683 DOI: 10.3390/genes12060886] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 12/14/2022] Open
Abstract
Little is known about the diversity and distribution of viruses infecting green sulfur bacteria (GSB) thriving in euxinic (sulfuric and anoxic) habitats, including gypsum karst lake ecosystems. In this study, we used targeted cell sorting combined with single-cell sequencing to gain insights into the gene content and genomic potential of viruses infecting sulfur-oxidizing bacteria Chlorobium clathratiforme, obtained from water samples collected during summer stratification in gypsum karst Lake Kirkilai (Lithuania). In total, 82 viral contigs were bioinformatically identified in 62 single amplified genomes (SAGs) of C. clathratiforme. The majority of viral gene and protein sequences showed little to no similarity with phage sequences in public databases, uncovering the vast diversity of previously undescribed GSB viruses. We observed a high level of lysogenization in the C. clathratiforme population, as 87% SAGs contained intact prophages. Among the thirty identified auxiliary metabolic genes (AMGs), two, thiosulfate sulfurtransferase (TST) and thioredoxin-dependent phosphoadenosine phosphosulfate (PAPS) reductase (cysH), were found to be involved in the oxidation of inorganic sulfur compounds, suggesting that viruses can influence the metabolism and cycling of this essential element. Finally, the analysis of CRISPR spacers retrieved from the consensus C. clathratiforme genome imply persistent and active virus–host interactions for several putative phages prevalent among C. clathratiforme SAGs. Overall, this study provides a glimpse into the diversity of phages associated with naturally occurring and highly abundant sulfur-oxidizing bacteria.
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Di Nezio F, Beney C, Roman S, Danza F, Buetti-Dinh A, Tonolla M, Storelli N. Anoxygenic photo- and chemo-synthesis of phototrophic sulfur bacteria from an alpine meromictic lake. FEMS Microbiol Ecol 2021; 97:6123714. [PMID: 33512460 PMCID: PMC7947596 DOI: 10.1093/femsec/fiab010] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/27/2021] [Indexed: 12/11/2022] Open
Abstract
Meromictic lakes are interesting ecosystems to study anaerobic microorganisms due their permanent stratification allowing the formation of a stable anoxic environment. The crenogenic meromictic Lake Cadagno harbors an important community of anoxygenic phototrophic sulfur bacteria responsible for almost half of its total productivity. Besides their ability to fix CO2 through photosynthesis, these microorganisms also showed high rates of dark carbon fixation via chemosyntesis. Here, we grew in pure cultures three populations of anoxygenic phototrophic sulfur bacteria previously isolated from the lake, accounting for 72.8% of the total microbial community and exibiting different phenotypes: (1) the motile, large-celled purple sulfur bacterium (PSB) Chromatium okenii, (2) the small-celled PSB Thiodictyon syntrophicum and (3) the green sulfur bacterium (GSB) Chlorobium phaeobacteroides. We measured their ability to fix CO2 through photo- and chemo-synthesis, both in situ in the lake and in laboratory under different incubation conditions. We also evaluated the efficiency and velocity of H2S photo-oxidation, an important reaction in the anoxygenic photosynthesis process. Our results confirm that phototrophic sulfur bacteria strongly fix CO2 in the presence of light and that oxygen increases chemosynthesis at night, in laboratory conditions. Moreover, substancial differences were displayed between the three selected populations in terms of activity and abundance.
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Affiliation(s)
- Francesco Di Nezio
- Laboratory of Applied Microbiology (LMA), Department of Environmental Constructions and Design (DACD), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), via Mirasole 22a, 6500 Bellinzona, Switzerland.,Microbiology Unit, Department of Botany and Plant Biology (BIVEG), University of Geneva, Quai Ernest-Ansermet 30, 1211 Geneva 4, 1211 Geneva, Switzerland
| | - Clarisse Beney
- Laboratory of Applied Microbiology (LMA), Department of Environmental Constructions and Design (DACD), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), via Mirasole 22a, 6500 Bellinzona, Switzerland.,Microbiology Unit, Department of Botany and Plant Biology (BIVEG), University of Geneva, Quai Ernest-Ansermet 30, 1211 Geneva 4, 1211 Geneva, Switzerland
| | - Samuele Roman
- Laboratory of Applied Microbiology (LMA), Department of Environmental Constructions and Design (DACD), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), via Mirasole 22a, 6500 Bellinzona, Switzerland.,Alpine Biology Center Foundation, via Mirasole 22a, 6500 Bellinzona, Switzerland
| | - Francesco Danza
- Laboratory of Applied Microbiology (LMA), Department of Environmental Constructions and Design (DACD), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), via Mirasole 22a, 6500 Bellinzona, Switzerland
| | - Antoine Buetti-Dinh
- Laboratory of Applied Microbiology (LMA), Department of Environmental Constructions and Design (DACD), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), via Mirasole 22a, 6500 Bellinzona, Switzerland
| | - Mauro Tonolla
- Laboratory of Applied Microbiology (LMA), Department of Environmental Constructions and Design (DACD), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), via Mirasole 22a, 6500 Bellinzona, Switzerland.,Microbiology Unit, Department of Botany and Plant Biology (BIVEG), University of Geneva, Quai Ernest-Ansermet 30, 1211 Geneva 4, 1211 Geneva, Switzerland.,Alpine Biology Center Foundation, via Mirasole 22a, 6500 Bellinzona, Switzerland
| | - Nicola Storelli
- Laboratory of Applied Microbiology (LMA), Department of Environmental Constructions and Design (DACD), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), via Mirasole 22a, 6500 Bellinzona, Switzerland
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Chan YF, Chiang PW, Tandon K, Rogozin D, Degermendzhi A, Zykov V, Tang SL. Spatiotemporal Changes in the Bacterial Community of the Meromictic Lake Uchum, Siberia. MICROBIAL ECOLOGY 2021; 81:357-369. [PMID: 32915303 DOI: 10.1007/s00248-020-01592-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 08/30/2020] [Indexed: 06/11/2023]
Abstract
Lake Uchum is a newly defined meromictic lake in Siberia with clear seasonal changes in its mixolimnion. This study characterized the temporal dynamics and vertical profile of bacterial communities in oxic and anoxic zones of the lake across all four seasons: October (autumn), March (winter), May (spring), and August (summer). Bacterial richness and diversity in the anoxic zone varied widely between time points. Proteobacteria was the dominant bacterial phylum throughout the oxic and anoxic zones across all four seasons. Alphaproteobacteria (Loktanella) and Gammaproteobacteria (Aliidiomarina) exhibited the highest abundance in the oxic and anoxic zone, respectively. Furthermore, there was a successional shift in sulfate-reducing bacteria (SRB) and sulfur-oxidizing bacteria in the anoxic zone across the seasons. The most dominant SRB, Desulfonatronovibrio sp., is likely one of the main producers of hydrogen sulfide (H2S) and typically accumulates the most H2S in winter. The representative anoxygenic phototrophic bacterial group in Lake Uchum was purple sulfur bacteria (PSB). PSB were dominant (60.76%) in summer, but only had 0.2-1.5% relative abundance from autumn to spring. Multivariate analysis revealed that the abundance of these SRB and PSB correlated to the concentration of H2S in Lake Uchum. Taken together, this study provides insights into the relationships between changes in bacterial community and environmental features in Lake Uchum.
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Affiliation(s)
- Ya-Fan Chan
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Pei-Wen Chiang
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Kshitij Tandon
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
- Bioinformatics Program, Institute of Information Science, Taiwan International Graduate Program, Academia Sinica, Taipei, 115, Taiwan
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, 300, Taiwan
| | - Denis Rogozin
- Institute of Biophysics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, 660036, Russia
- Siberia Federal University, Krasnoyarsk, 660041, Russia
| | - Andrey Degermendzhi
- Institute of Biophysics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, 660036, Russia
| | - Vladimir Zykov
- Institute of Biophysics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, 660036, Russia
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.
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11
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Chen M, Jiao YY, Zhang YQ, Krumholz LR, Ren JX, Li ZH, Zhao LY, Song HT, Lu JD. Succession of sulfur bacteria during decomposition of cyanobacterial bloom biomass in the shallow Lake Nanhu: An ex situ mesocosm study. CHEMOSPHERE 2020; 256:127101. [PMID: 32450355 DOI: 10.1016/j.chemosphere.2020.127101] [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: 01/17/2020] [Revised: 04/26/2020] [Accepted: 05/15/2020] [Indexed: 06/11/2023]
Abstract
Previous studies of the dynamics of sulfate-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB) have focused on deep stratified lakes. The objective of this study is to present an in-depth investigation of the structure and dynamics of sulfur bacteria (including SRB and SOB) in the water column of shallow freshwater lakes. A cyanobacterial bloom biomass (CBB)-amended mesocosm experiment was conducted in this study, in which water was taken from a shallow eutrophic lake with sulfate levels near 40 mg L-1. Illumina sequencing was used to investigate SRB and SOB species involved in CBB decomposition and the effects of the increases in sulfate input on the water column microbial community structure. The accumulation of dissolved sulfide (∑H2S) produced by SRB during CBB decomposition stimulated the growth of SOB, and ∑H2S was then oxidized back to sulfate by SOB in the water column. Chlorobaculum sequences (the main SOB species in the study) were significantly influenced by increases in sulfate input, with relative abundance increasing approximately four-fold in treatments amended with 40 mg L-1 sulfate (referred to as 40S) when compared to the treatment without additional sulfate addition (referred to as CU). Additionally, an increase in SOB number was observed from day 26-37, concurrent with the decrease in SRB number, indicating the succession of sulfur bacteria. These findings suggest that biological sulfur oxidation and succession of sulfur bacteria occur in the water column during CBB decomposition in shallow freshwater ecosystems, and the increases in sulfate input stimulate microbial sulfur oxidation.
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Affiliation(s)
- Mo Chen
- Faculty of Resources and Environmental Science, Hubei University, Wuhan, 430062, China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Yi-Ying Jiao
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, College of Resources and Environmental Engineering, Hubei University of Technology, Wuhan, China
| | - Ya-Qing Zhang
- Faculty of Resources and Environmental Science, Hubei University, Wuhan, 430062, China
| | - Lee R Krumholz
- Department of Botany & Microbiology, University of Oklahoma, Norman, OK, USA
| | - Jun-Xian Ren
- Faculty of Resources and Environmental Science, Hubei University, Wuhan, 430062, China
| | - Zhao-Hua Li
- Faculty of Resources and Environmental Science, Hubei University, Wuhan, 430062, China
| | - Li-Ya Zhao
- Faculty of Resources and Environmental Science, Hubei University, Wuhan, 430062, China
| | - Hui-Ting Song
- Faculty of Resources and Environmental Science, Hubei University, Wuhan, 430062, China
| | - Jin-Deng Lu
- Faculty of Resources and Environmental Science, Hubei University, Wuhan, 430062, China.
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12
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Luedin SM, Storelli N, Danza F, Roman S, Wittwer M, Pothier JF, Tonolla M. Mixotrophic Growth Under Micro-Oxic Conditions in the Purple Sulfur Bacterium " Thiodictyon syntrophicum". Front Microbiol 2019; 10:384. [PMID: 30891015 PMCID: PMC6413534 DOI: 10.3389/fmicb.2019.00384] [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: 10/03/2018] [Accepted: 02/13/2019] [Indexed: 12/23/2022] Open
Abstract
The microbial ecosystem of the meromictic Lake Cadagno (Ticino, Swiss Alps) has been studied intensively in order to understand structure and functioning of the anoxygenic phototrophic sulfur bacteria community living in the chemocline. It has been found that the purple sulfur bacterium "Thiodictyon syntrophicum" strain Cad16T, belonging to the Chromatiaceae, fixes around 26% of all bulk inorganic carbon in the chemocline, both during day and night. With this study, we elucidated for the first time the mode of carbon fixation of str. Cad16T under micro-oxic conditions with a combination of long-term monitoring of key physicochemical parameters with CTD, 14C-incorporation experiments and quantitative proteomics using in-situ dialysis bag incubations of str. Cad16T cultures. Regular vertical CTD profiling during the study period in summer 2017 revealed that the chemocline sank from 12 to 14 m which was accompanied by a bloom of cyanobacteria and the subsequent oxygenation of the deeper water column. Sampling was performed both day and night. CO2 assimilation rates were higher during the light period compared to those in the dark, both in the chemocline population and in the incubated cultures. The relative change in the proteome between day and night (663 quantified proteins) comprised only 1% of all proteins encoded in str. Cad16T. Oxidative respiration pathways were upregulated at light, whereas stress-related mechanisms prevailed during the night. These results indicate that low light availability and the co-occurring oxygenation of the chemocline induced mixotrophic growth in str. Cad16T. Our study thereby helps to further understand the consequences micro-oxic conditions for phototrophic sulfur oxidizing bacteria. The complete proteome data have been deposited to the ProteomeXchange database with identifier PXD010641.
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Affiliation(s)
- Samuel M. Luedin
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
- Laboratory of Applied Microbiology, Department of Environment, Constructions and Design, University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Spiez Laboratory, Biology Division, Federal Office for Civil Protection, Spiez, Switzerland
| | - Nicola Storelli
- Laboratory of Applied Microbiology, Department of Environment, Constructions and Design, University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
| | - Francesco Danza
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
- Laboratory of Applied Microbiology, Department of Environment, Constructions and Design, University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
| | - Samuele Roman
- Laboratory of Applied Microbiology, Department of Environment, Constructions and Design, University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
| | - Matthias Wittwer
- Spiez Laboratory, Biology Division, Federal Office for Civil Protection, Spiez, Switzerland
| | - Joël F. Pothier
- Environmental Genomics and System Biology Research Group, Institute of Natural Resource Sciences, Zurich University of Applied Sciences (ZHAW), Wädenswil, Switzerland
| | - Mauro Tonolla
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
- Laboratory of Applied Microbiology, Department of Environment, Constructions and Design, University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
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