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Grim SL, Stuart DG, Aron P, Levin NE, Kinsman-Costello L, Waldbauer JR, Dick GJ. Seasonal shifts in community composition and proteome expression in a sulphur-cycling cyanobacterial mat. Environ Microbiol 2023; 25:2516-2533. [PMID: 37596970 DOI: 10.1111/1462-2920.16480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 07/29/2023] [Indexed: 08/21/2023]
Abstract
Seasonal changes in light and physicochemical conditions have strong impacts on cyanobacteria, but how they affect community structure, metabolism, and biogeochemistry of cyanobacterial mats remains unclear. Light may be particularly influential for cyanobacterial mats exposed to sulphide by altering the balance of oxygenic photosynthesis and sulphide-driven anoxygenic photosynthesis. We studied temporal shifts in irradiance, water chemistry, and community structure and function of microbial mats in the Middle Island Sinkhole (MIS), where anoxic and sulphate-rich groundwater provides habitat for cyanobacteria that conduct both oxygenic and anoxygenic photosynthesis. Seasonal changes in light and groundwater chemistry were accompanied by shifts in bacterial community composition, with a succession of dominant cyanobacteria from Phormidium to Planktothrix, and an increase in diatoms, sulphur-oxidizing bacteria, and sulphate-reducing bacteria from summer to autumn. Differential abundance of cyanobacterial light-harvesting proteins likely reflects a physiological response of cyanobacteria to light level. Beggiatoa sulphur oxidation proteins were more abundant in autumn. Correlated abundances of taxa through time suggest interactions between sulphur oxidizers and sulphate reducers, sulphate reducers and heterotrophs, and cyanobacteria and heterotrophs. These results support the conclusion that seasonal change, including light availability, has a strong influence on community composition and biogeochemical cycling of sulphur and O2 in cyanobacterial mats.
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Affiliation(s)
- Sharon L Grim
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Dack G Stuart
- Cooperative Institute for Great Lakes Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Phoebe Aron
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Naomi E Levin
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Jacob R Waldbauer
- Department of the Geophysical Sciences, University of Chicago, Chicago, Illinois, USA
| | - Gregory J Dick
- Department of Earth and Environmental Sciences, Cooperative Institute for Great Lakes Research, University of Michigan, Ann Arbor, Michigan, USA
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2
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Cremin K, Duxbury SJN, Rosko J, Soyer OS. Formation and emergent dynamics of spatially organized microbial systems. Interface Focus 2023; 13:20220062. [PMID: 36789239 PMCID: PMC9912014 DOI: 10.1098/rsfs.2022.0062] [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: 10/25/2022] [Accepted: 12/19/2022] [Indexed: 02/12/2023] Open
Abstract
Spatial organization is the norm rather than the exception in the microbial world. While the study of microbial physiology has been dominated by studies in well-mixed cultures, there is now increasing interest in understanding the role of spatial organization in microbial physiology, coexistence and evolution. Where studied, spatial organization has been shown to influence all three of these aspects. In this mini review and perspective article, we emphasize that the dynamics within spatially organized microbial systems (SOMS) are governed by feedbacks between local physico-chemical conditions, cell physiology and movement, and evolution. These feedbacks can give rise to emergent dynamics, which need to be studied through a combination of spatio-temporal measurements and mathematical models. We highlight the initial formation of SOMS and their emergent dynamics as two open areas of investigation for future studies. These studies will benefit from the development of model systems that can mimic natural ones in terms of species composition and spatial structure.
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Affiliation(s)
- Kelsey Cremin
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | | | - Jerko Rosko
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Orkun S. Soyer
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
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3
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Wada N, Iguchi A, Urabe Y, Yoshioka Y, Abe N, Takase K, Hayashi S, Kawanabe S, Sato Y, Tang SL, Mano N. Microbial mat compositions and localization patterns explain the virulence of black band disease in corals. NPJ Biofilms Microbiomes 2023; 9:15. [PMID: 37015942 PMCID: PMC10073141 DOI: 10.1038/s41522-023-00381-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 03/13/2023] [Indexed: 04/06/2023] Open
Abstract
Black band disease (BBD) in corals is characterized by a distinctive, band-like microbial mat, which spreads across the tissues and often kills infected colonies. The microbial mat is dominated by cyanobacteria but also commonly contains sulfide-oxidizing bacteria (SOB), sulfate-reducing bacteria (SRB), and other microbes. The migration rate in BBD varies across different environmental conditions, including temperature, light, and pH. However, whether variations in the migration rates reflect differences in the microbial consortium within the BBD mat remains unknown. Here, we show that the micro-scale surface structure, bacterial composition, and spatial distribution differed across BBD lesions with different migration rates. The migration rate was positively correlated with the relative abundance of potential SOBs belonging to Arcobacteraceae localized in the middle layer within the mat and negatively correlated with the relative abundance of other potential SOBs belonging to Rhodobacteraceae. Our study highlights the microbial composition in BBD as an important determinant of virulence.
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Affiliation(s)
- Naohisa Wada
- Biodiversity Research Center, Academia Sinica, No.128, Sec 2, Academia Rd, Nangang, Taipei, 11529, Taiwan
- Department of Marine Science and Resources, College of Bioresource Science, Nihon University, Fujisawa, Kanagawa, 252-0813, Japan
| | - Akira Iguchi
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8567, Japan
- Research Laboratory on Environmentally-conscious Developments and Technologies [E-code], National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8567, Japan
| | - Yuta Urabe
- Department of Marine Science and Resources, College of Bioresource Science, Nihon University, Fujisawa, Kanagawa, 252-0813, Japan
| | - Yuki Yoshioka
- Department of Bioresources Engineering, National Institute of Technology, Okinawa College, 905 Henoko, Nago-City, Okinawa, 905-2192, Japan
| | - Natsumi Abe
- Department of Marine Science and Resources, College of Bioresource Science, Nihon University, Fujisawa, Kanagawa, 252-0813, Japan
| | - Kazuki Takase
- Department of Marine Science and Resources, College of Bioresource Science, Nihon University, Fujisawa, Kanagawa, 252-0813, Japan
| | - Shuji Hayashi
- Department of Marine Science and Resources, College of Bioresource Science, Nihon University, Fujisawa, Kanagawa, 252-0813, Japan
| | - Saeko Kawanabe
- Department of Marine Science and Resources, College of Bioresource Science, Nihon University, Fujisawa, Kanagawa, 252-0813, Japan
| | - Yui Sato
- College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, No.128, Sec 2, Academia Rd, Nangang, Taipei, 11529, Taiwan.
| | - Nobuhiro Mano
- Department of Marine Science and Resources, College of Bioresource Science, Nihon University, Fujisawa, Kanagawa, 252-0813, Japan.
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Gaisin VA, Kooger R, Grouzdev DS, Gorlenko VM, Pilhofer M. Cryo-Electron Tomography Reveals the Complex Ultrastructural Organization of Multicellular Filamentous Chloroflexota ( Chloroflexi) Bacteria. Front Microbiol 2020; 11:1373. [PMID: 32670237 PMCID: PMC7332563 DOI: 10.3389/fmicb.2020.01373] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 05/27/2020] [Indexed: 11/13/2022] Open
Abstract
The cell biology of Chloroflexota is poorly studied. We applied cryo-focused ion beam milling and cryo-electron tomography to study the ultrastructural organization of thermophilic Roseiflexus castenholzii and Chloroflexus aggregans, and mesophilic “Ca. Viridilinea mediisalina.” These species represent the three main lineages within a group of multicellular filamentous anoxygenic phototrophic Chloroflexota bacteria belonging to the Chloroflexales order. We found surprising structural complexity in the Chloroflexales. As with filamentous cyanobacteria, cells of C. aggregans and “Ca. Viridilinea mediisalina” share the outer membrane-like layers of their intricate multilayer cell envelope. Additionally, cells of R. castenholzii and “Ca. Viridilinea mediisalina” are connected by septal channels that resemble cyanobacterial septal junctions. All three strains possess long pili anchored close to cell-to-cell junctions, a morphological feature comparable to that observed in cyanobacteria. The cytoplasm of the Chloroflexales bacteria is crowded with intracellular organelles such as different types of storage granules, membrane vesicles, chlorosomes, gas vesicles, chemoreceptor-like arrays, and cytoplasmic filaments. We observed a higher level of complexity in the mesophilic strain compared to the thermophilic strains with regards to the composition of intracellular bodies and the organization of the cell envelope. The ultrastructural details that we describe in these Chloroflexales bacteria will motivate further cell biological studies, given that the function and evolution of the many discovered morphological traits remain enigmatic in this diverse and widespread bacterial group.
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Affiliation(s)
- Vasil A Gaisin
- Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia.,Algatech, Institute of Microbiology of the Czech Academy of Sciences, Třeboň, Czechia
| | - Romain Kooger
- Institute of Molecular Biology & Biophysics, Eidgenössische Technische Hochschule Zürich, Zurich, Switzerland
| | - Denis S Grouzdev
- Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Vladimir M Gorlenko
- Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Martin Pilhofer
- Institute of Molecular Biology & Biophysics, Eidgenössische Technische Hochschule Zürich, Zurich, Switzerland
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Wilmeth DT, Johnson HA, Stamps BW, Berelson WM, Stevenson BS, Nunn HS, Grim SL, Dillon ML, Paradis O, Corsetti FA, Spear JR. Environmental and Biological Influences on Carbonate Precipitation Within Hot Spring Microbial Mats in Little Hot Creek, CA. Front Microbiol 2018; 9:1464. [PMID: 30057571 PMCID: PMC6053513 DOI: 10.3389/fmicb.2018.01464] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 06/12/2018] [Indexed: 11/18/2022] Open
Abstract
Microbial mats are found in a variety of modern environments, with evidence for their presence as old as the Archean. There is much debate about the rates and conditions of processes that eventually lithify and preserve mats as microbialites. Here, we apply novel tracer experiments to quantify both mat biomass addition and the formation of CaCO3. Microbial mats from Little Hot Creek (LHC), California, contain calcium carbonate that formed within multiple mat layers, and thus constitute a good test case to investigate the relationship between the rate of microbial mat growth and carbonate precipitation. The laminated LHC mats were divided into four layers via color and fabric, and waters within and above the mat were collected to determine their carbonate saturation states. Samples of the microbial mat were also collected for 16S rRNA analysis of microbial communities in each layer. Rates of carbonate precipitation and carbon fixation were measured in the laboratory by incubating homogenized samples from each mat layer with δ13C-labeled HCO3- for 24 h. Comparing these rates with those from experimental controls, poisoned with NaN3 and HgCl2, allowed for differences in biogenic and abiogenic precipitation to be determined. Carbon fixation rates were highest in the top layer of the mat (0.17% new organic carbon/day), which also contained the most phototrophs. Isotope-labeled carbonate was precipitated in all four layers of living and poisoned mat samples. In the top layer, the precipitation rate in living mat samples was negligible although abiotic precipitation occurred. In contrast, the bottom three layers exhibited biologically enhanced carbonate precipitation. The lack of correlation between rates of carbon fixation and biogenic carbonate precipitation suggests that processes other than autotrophy may play more significant roles in the preservation of mats as microbialites.
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Affiliation(s)
- Dylan T. Wilmeth
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Hope A. Johnson
- Department of Biological Science, California State University, Fullerton, Fullerton, CA, United States
| | - Blake W. Stamps
- Geo- Environmental- Microbiology Laboratory, Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, United States
| | - William M. Berelson
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Bradley S. Stevenson
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, United States
| | - Heather S. Nunn
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, United States
| | - Sharon L. Grim
- Geomicrobiology Laboratory, Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, United States
| | - Megan L. Dillon
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, CA, United States
| | - Olivia Paradis
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Frank A. Corsetti
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - John R. Spear
- Geo- Environmental- Microbiology Laboratory, Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, United States
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6
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Hörnlein C, Confurius-Guns V, Stal LJ, Bolhuis H. Daily rhythmicity in coastal microbial mats. NPJ Biofilms Microbiomes 2018; 4:11. [PMID: 29796291 PMCID: PMC5953948 DOI: 10.1038/s41522-018-0054-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 03/26/2018] [Accepted: 04/17/2018] [Indexed: 12/31/2022] Open
Abstract
Cyanobacteria are major primary producers in coastal microbial mats and provide biochemical energy, organic carbon, and bound nitrogen to the mat community through oxygenic photosynthesis and dinitrogen fixation. In order to anticipate the specific requirements to optimize their metabolism and growth during a day-and-night cycle, Cyanobacteria possess a unique molecular timing mechanism known as the circadian clock that is well-studied under laboratory conditions but little is known about its function in a natural complex community. Here, we investigated daily rhythmicity of gene expression in a coastal microbial mat community sampled at 6 time points during a 24-h period. In order to identify diel expressed genes, meta-transcriptome data was fitted to periodic functions. Out of 24,035 conserved gene transcript clusters, approximately 7% revealed a significant rhythmic expression pattern. These rhythmic genes were assigned to phototrophic micro-eukaryotes, Cyanobacteria but also to Proteobacteria and Bacteroidetes. Analysis of MG-RAST annotated genes and mRNA recruitment analysis of two cyanobacterial and three proteobacterial microbial mat members confirmed that homologs of the cyanobacterial circadian clock genes were also found in other bacterial members of the microbial mat community. These results suggest that various microbial mat members other than Cyanobacteria have their own molecular clock, which can be entrained by a cocktail of Zeitgebers such as light, temperature or metabolites from neighboring species. Hence, microbial mats can be compared to a complex organism consisting of multiple sub-systems that have to be entrained in a cooperative way such that the corpus functions optimally.
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Affiliation(s)
- Christine Hörnlein
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, The Netherlands
| | - Veronique Confurius-Guns
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, The Netherlands
| | - Lucas J Stal
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, The Netherlands.,2Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Henk Bolhuis
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, The Netherlands
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7
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Wilde A, Mullineaux CW. Light-controlled motility in prokaryotes and the problem of directional light perception. FEMS Microbiol Rev 2017; 41:900-922. [PMID: 29077840 PMCID: PMC5812497 DOI: 10.1093/femsre/fux045] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 09/12/2017] [Indexed: 12/02/2022] Open
Abstract
The natural light environment is important to many prokaryotes. Most obviously, phototrophic prokaryotes need to acclimate their photosynthetic apparatus to the prevailing light conditions, and such acclimation is frequently complemented by motility to enable cells to relocate in search of more favorable illumination conditions. Non-phototrophic prokaryotes may also seek to avoid light at damaging intensities and wavelengths, and many prokaryotes with diverse lifestyles could potentially exploit light signals as a rich source of information about their surroundings and a cue for acclimation and behavior. Here we discuss our current understanding of the ways in which bacteria can perceive the intensity, wavelength and direction of illumination, and the signal transduction networks that link light perception to the control of motile behavior. We discuss the problems of light perception at the prokaryotic scale, and the challenge of directional light perception in small bacterial cells. We explain the peculiarities and the common features of light-controlled motility systems in prokaryotes as diverse as cyanobacteria, purple photosynthetic bacteria, chemoheterotrophic bacteria and haloarchaea.
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Affiliation(s)
- Annegret Wilde
- Institute of Biology III, University of Freiburg, 79104 Freiburg, Germany
- BIOSS Centre of Biological Signalling Studies, University of Freiburg, 79106 Freiburg, Germany
| | - Conrad W. Mullineaux
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
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8
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Lichtenberg M, Brodersen KE, Kühl M. Radiative Energy Budgets of Phototrophic Surface-Associated Microbial Communities and their Photosynthetic Efficiency Under Diffuse and Collimated Light. Front Microbiol 2017; 8:452. [PMID: 28400749 PMCID: PMC5368174 DOI: 10.3389/fmicb.2017.00452] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 03/03/2017] [Indexed: 11/13/2022] Open
Abstract
We investigated the radiative energy budgets of a heterogeneous photosynthetic coral reef sediment and a compact uniform cyanobacterial biofilm on top of coastal sediment. By combining electrochemical, thermocouple and fiber-optic microsensor measurements of O2, temperature and light, we could calculate the proportion of the absorbed light energy that was either dissipated as heat or conserved by photosynthesis. We show, across a range of different incident light regimes, that such radiative energy budgets are highly dominated by heat dissipation constituting up to 99.5% of the absorbed light energy. Highest photosynthetic energy conservation efficiency was found in the coral sediment under low light conditions and amounted to 18.1% of the absorbed light energy. Additionally, the effect of light directionality, i.e., diffuse or collimated light, on energy conversion efficiency was tested on the two surface-associated systems. The effects of light directionality on the radiative energy budgets of these phototrophic communities were not unanimous but, resulted in local spatial differences in heat-transfer, gross photosynthesis, and light distribution. The light acclimation index, Ek, i.e., the irradiance at the onset of saturation of photosynthesis, was >2 times higher in the coral sediment compared to the biofilm and changed the pattern of photosynthetic energy conservation under light-limiting conditions. At moderate to high incident irradiances, the photosynthetic conservation of absorbed energy was highest in collimated light; a tendency that changed in the biofilm under sub-saturating incident irradiances, where higher photosynthetic efficiencies were observed under diffuse light. The aim was to investigate how the physical structure and light propagation affected energy budgets and light utilization efficiencies in loosely organized vs. compact phototrophic sediment under diffuse and collimated light. Our results suggest that the optical properties and the structural organization of phytoelements are important traits affecting the photosynthetic efficiency of biofilms and sediments.
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Affiliation(s)
- Mads Lichtenberg
- Marine Biological Section, Department of Biology, University of Copenhagen Helsingør, Denmark
| | - Kasper E Brodersen
- Marine Biological Section, Department of Biology, University of Copenhagen Helsingør, Denmark
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of CopenhagenHelsingør, Denmark; Climate Change Cluster, University of Technology SydneyUltimo, NSW, Australia
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Biddanda BA, McMillan AC, Long SA, Snider MJ, Weinke AD. Seeking sunlight: rapid phototactic motility of filamentous mat-forming cyanobacteria optimize photosynthesis and enhance carbon burial in Lake Huron's submerged sinkholes. Front Microbiol 2015; 6:930. [PMID: 26441867 PMCID: PMC4561352 DOI: 10.3389/fmicb.2015.00930] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 08/24/2015] [Indexed: 11/13/2022] Open
Abstract
We studied the motility of filamentous mat-forming cyanobacteria consisting primarily of Oscillatoria-like cells growing under low-light, low-oxygen, and high-sulfur conditions in Lake Huron's submerged sinkholes using in situ observations, in vitro measurements and time-lapse microscopy. Gliding movement of the cyanobacterial trichomes (100-10,000 μm long filaments, composed of cells ∼10 μm wide and ∼3 μm tall) revealed individual as well as group-coordinated motility. When placed in a petri dish and dispersed in ground water from the sinkhole, filaments re-aggregated into defined colonies within minutes, then dispersed again. Speed of individual filaments increased with temperature from ∼50 μm min(-1) or ∼15 body lengths min(-1) at 10°C to ∼215 μm min(-1) or ∼70 body lengths min(-1) at 35°C - rates that are rapid relative to non-flagellated/ciliated microbes. Filaments exhibited precise and coordinated positive phototaxis toward pinpoints of light and congregated under the light of foil cutouts. Such light-responsive clusters showed an increase in photosynthetic yield - suggesting phototactic motility aids in light acquisition as well as photosynthesis. Once light source was removed, filaments slowly spread out evenly and re-aggregated, demonstrating coordinated movement through inter-filament communication regardless of light. Pebbles and pieces of broken shells placed upon intact mat were quickly covered by vertically motile filaments within hours and became fully buried in the anoxic sediments over 3-4 diurnal cycles - likely facilitating the preservation of falling debris. Coordinated horizontal and vertical filament motility optimize mat cohesion and dynamics, photosynthetic efficiency and sedimentary carbon burial in modern-day sinkhole habitats that resemble the shallow seas in Earth's early history. Analogous cyanobacterial motility may have played a key role in the oxygenation of the planet by optimizing photosynthesis while favoring carbon burial.
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Affiliation(s)
- Bopaiah A. Biddanda
- Annis Water Resources Institute, Grand Valley State University, MuskegonMI, USA
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10
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Pyrosequencing analysis of bacterial communities in biofilms from different pipe materials in a city drinking water distribution system of East China. Appl Microbiol Biotechnol 2015; 99:10713-24. [DOI: 10.1007/s00253-015-6885-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 07/21/2015] [Indexed: 12/19/2022]
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11
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Abstract
Chemotaxis affords motile cells the ability to rapidly respond to environmental challenges by navigating cells to niches favoring growth. Such a property results from the activities of dedicated signal transduction systems on the motility apparatus, such as flagella, type IV pili, and gliding machineries. Once cells have reached a niche with favorable conditions, they often stop moving and aggregate into complex communities termed biofilms. An intermediate and reversible stage that precedes commitment to permanent adhesion often includes transient cell-cell contacts between motile cells. Chemotaxis signaling has been implicated in modulating the transient aggregation of motile cells. Evidence further indicates that chemotaxis-dependent transient cell aggregation events are behavioral responses to changes in metabolic cues that temporarily prohibit permanent attachment by maintaining motility and chemotaxis. This minireview discusses a few examples illustrating the role of chemotaxis signaling in the initiation of cell-cell contacts in bacteria moving via flagella, pili, or gliding.
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12
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Castenholz RW. Portrait of a Geothermal Spring, Hunter's Hot Springs, Oregon. Life (Basel) 2015; 5:332-47. [PMID: 25633225 PMCID: PMC4390855 DOI: 10.3390/life5010332] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 01/07/2015] [Accepted: 01/21/2015] [Indexed: 11/16/2022] Open
Abstract
Although alkaline Hunter's Hot Springs in southeastern Oregon has been studied extensively for over 40 years, most of these studies and the subsequent publications were before the advent of molecular methods. However, there are many field observations and laboratory experiments that reveal the major aspects of the phototrophic species composition within various physical and chemical gradients of these springs. Relatively constant temperature boundaries demark the upper boundary of the unicellular cyanobacterium, Synechococcus at 73-74 °C (the world-wide upper limit for photosynthesis), and 68-70 °C the upper limit for Chloroflexus. The upper limit for the cover of the filamentous cyanobacterium, Geitlerinema (Oscillatoria) is at 54-55 °C, and the in situ lower limit at 47-48 °C for all three of these phototrophs due to the upper temperature limit for the grazing ostracod, Thermopsis. The in situ upper limit for the cyanobacteria Pleurocapsa and Calothrix is at ~47-48 °C, which are more grazer-resistant and grazer dependent. All of these demarcations are easily visible in the field. In addition, there is a biosulfide production in some sections of the springs that have a large impact on the microbiology. Most of the temperature and chemical limits have been explained by field and laboratory experiments.
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Affiliation(s)
- Richard W Castenholz
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403, USA.
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13
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Richardson LL, Stanić D, May A, Brownell A, Gantar M, Campagna SR. Ecology and Physiology of the Pathogenic Cyanobacterium Roseofilum reptotaenium. Life (Basel) 2014; 4:968-87. [PMID: 25517133 PMCID: PMC4284477 DOI: 10.3390/life4040968] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 11/24/2014] [Accepted: 12/04/2014] [Indexed: 11/16/2022] Open
Abstract
Roseofilum reptotaenium is a gliding, filamentous, phycoerythrin-rich cyanobacterium that has been found only in the horizontally migrating, pathogenic microbial mat, black band disease (BBD) on Caribbean corals. R. reptotaenium dominates the BBD mat in terms of biomass and motility, and the filaments form the mat fabric. This cyanobacterium produces the cyanotoxin microcystin, predominately MC-LR, and can tolerate high levels of sulfide produced by sulfate reducing bacteria (SRB) that are also associated with BBD. Laboratory cultures of R. reptotaenium infect coral fragments, suggesting that the cyanobacterium is the primary pathogen of BBD, but since this species cannot grow axenically and Koch's Postulates cannot be fulfilled, it cannot be proposed as a primary pathogen. However, R. reptotaenium does play several major pathogenic roles in this polymicrobial disease. Here, we provide an overview of the ecology of this coral pathogen and present new information on R. reptotaenium ecophysiology, including roles in the infection process, chemotactic and other motility responses, and the effect of pH on growth and motility. Additionally, we show, using metabolomics, that exposure of the BBD microbial community to the cyanotoxin MC-LR affects community metabolite profiles, in particular those associated with nucleic acid biosynthesis.
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Affiliation(s)
- Laurie L Richardson
- Department of Biological Sciences, Florida International University, Miami, FL 33199, USA.
| | - Dina Stanić
- Department of Biological Sciences, Florida International University, Miami, FL 33199, USA.
| | - Amanda May
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA.
| | - Abigael Brownell
- Department of Biological Sciences, Florida International University, Miami, FL 33199, USA.
| | - Miroslav Gantar
- Department of Biological Sciences, Florida International University, Miami, FL 33199, USA.
| | - Shawn R Campagna
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA.
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Douterelo I, Husband S, Boxall JB. The bacteriological composition of biomass recovered by flushing an operational drinking water distribution system. WATER RESEARCH 2014; 54:100-114. [PMID: 24565801 DOI: 10.1016/j.watres.2014.01.049] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 01/23/2014] [Accepted: 01/26/2014] [Indexed: 06/03/2023]
Abstract
This study investigates the influence of pipe characteristics on the bacteriological composition of material mobilised from a drinking water distribution system (DWDS) and the impact of biofilm removal on water quality. Hydrants in a single UK Distribution Management Area (DMA) with both polyethylene and cast iron pipe sections were subjected to incremental increases in flow to mobilise material from the pipe walls. Turbidity was monitored during these operations and water samples were collected for physico-chemical and bacteriological analysis. DNA was extracted from the material mobilised into the bulk water before and during flushing. Bacterial tag-encoded 454 pyrosequencing was then used to characterize the bacterial communities present in this material. Turbidity values were high in the samples from cast iron pipes. Iron, aluminium, manganese and phosphate concentrations were found to correlate to observed turbidity. The bacterial community composition of the material mobilised from the pipes was significantly different between plastic and cast iron pipe sections (p < 0.5). High relative abundances of Alphaproteobacteria (23.3%), Clostridia (10.3%) and Actinobacteria (10.3%) were detected in the material removed from plastic pipes. Sequences related to Alphaproteobacteria (22.8%), Bacilli (16.6%), and Gammaproteobacteria (1.4%) were predominant in the samples obtained from cast iron pipes. The highest species richness and diversity were found in the samples from material mobilised from plastic pipes. Spirochaeta spp., Methylobacterium spp. Clostridium spp. and Desulfobacterium spp., were the most represented genera in the material obtained prior to and during the flushing of the plastic pipes. In cast iron pipes a high relative abundance of bacteria able to utilise different iron and manganese compounds were found such as Lysinibacillus spp., Geobacillus spp. and Magnetobacterium spp.
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Affiliation(s)
- I Douterelo
- Pennine Water Group, Department of Civil and Structural Engineering, Sir Frederick Mappin Building, University of Sheffield, Sheffield S1 3JD, UK.
| | - S Husband
- Pennine Water Group, Department of Civil and Structural Engineering, Sir Frederick Mappin Building, University of Sheffield, Sheffield S1 3JD, UK
| | - J B Boxall
- Pennine Water Group, Department of Civil and Structural Engineering, Sir Frederick Mappin Building, University of Sheffield, Sheffield S1 3JD, UK
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Voorhies AA, Biddanda BA, Kendall ST, Jain S, Marcus DN, Nold SC, Sheldon ND, Dick GJ. Cyanobacterial life at low O(2): community genomics and function reveal metabolic versatility and extremely low diversity in a Great Lakes sinkhole mat. GEOBIOLOGY 2012; 10:250-67. [PMID: 22404795 DOI: 10.1111/j.1472-4669.2012.00322.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Cyanobacteria are renowned as the mediators of Earth's oxygenation. However, little is known about the cyanobacterial communities that flourished under the low-O(2) conditions that characterized most of their evolutionary history. Microbial mats in the submerged Middle Island Sinkhole of Lake Huron provide opportunities to investigate cyanobacteria under such persistent low-O(2) conditions. Here, venting groundwater rich in sulfate and low in O(2) supports a unique benthic ecosystem of purple-colored cyanobacterial mats. Beneath the mat is a layer of carbonate that is enriched in calcite and to a lesser extent dolomite. In situ benthic metabolism chambers revealed that the mats are net sinks for O(2), suggesting primary production mechanisms other than oxygenic photosynthesis. Indeed, (14)C-bicarbonate uptake studies of autotrophic production show variable contributions from oxygenic and anoxygenic photosynthesis and chemosynthesis, presumably because of supply of sulfide. These results suggest the presence of either facultatively anoxygenic cyanobacteria or a mix of oxygenic/anoxygenic types of cyanobacteria. Shotgun metagenomic sequencing revealed a remarkably low-diversity mat community dominated by just one genotype most closely related to the cyanobacterium Phormidium autumnale, for which an essentially complete genome was reconstructed. Also recovered were partial genomes from a second genotype of Phormidium and several Oscillatoria. Despite the taxonomic simplicity, diverse cyanobacterial genes putatively involved in sulfur oxidation were identified, suggesting a diversity of sulfide physiologies. The dominant Phormidium genome reflects versatile metabolism and physiology that is specialized for a communal lifestyle under fluctuating redox conditions and light availability. Overall, this study provides genomic and physiologic insights into low-O(2) cyanobacterial mat ecosystems that played crucial geobiological roles over long stretches of Earth history.
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Affiliation(s)
- A A Voorhies
- Deptartment of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA
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16
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Abstract
Singlet oxygen is the primary agent of photooxidative stress in microorganisms. In photosynthetic microorganisms, sensitized generation by pigments of the photosystems is the main source of singlet oxygen and, in nonphotosynthetic microorganisms, cellular cofactors such as flavins, rhodopsins, quinones, and porphyrins serve as photosensitizer. Singlet oxygen rapidly reacts with a wide range of cellular macromolecules including proteins, lipids, DNA, and RNA, and thereby further reactive substances including organic peroxides and sulfoxides are formed. Microorganisms that face high light intensities or exhibit potent photosensitizers have evolved specific mechanisms to prevent photooxidative stress. These mechanisms include the use of quenchers, such as carotenoids, which interact either with excited photosensitizer molecules or singlet oxygen itself to prevent damage of cellular molecules. Scavengers like glutathione react with singlet oxygen. Despite those protection mechanisms, damage by reactions with singlet oxygen on cellular macromolecules disturbs cellular functions. Microorganisms that regularly face photooxidative stress have evolved specific systems to sense singlet oxygen and tightly control the removal of singlet oxygen reaction products. Responses to photooxidative stress have been investigated in a range of photosynthetic and nonphotosynthetic microorganisms. However, detailed knowledge on the regulation of this response has only been obtained for the phototrophic alpha-proteobacterium Rhodobacter sphaeroides. In this organism and in related proteobacteria, the extracytoplasmic function (ECF) sigma factor RpoE is released from the cognate antisigma factor ChrR in the presence of singlet oxygen and triggers the expression of genes providing protection against photooxidative stress. Recent experiments show that singlet oxygen acts as a signal, which is sensed by yet unknown components and leads to proteolysis of ChrR. RpoE induces expression of a second alternative sigma factor, RpoH(II), which controls a large set of genes that partially overlaps with the heat-shock response controlled by RpoH(I). In addition to the transcriptional control of gene regulation by alternative sigma factors, a set of noncoding small RNAs (sRNAs) appear to affect the synthesis of several proteins involved in the response to photooxidative stress. The interaction of mRNA targets with those sRNAs is usually mediated by the RNA chaperone Hfq. Deletion of the gene encoding Hfq leads to a singlet oxygen-sensitive phenotype, which underlines the control of gene regulation on the posttranscriptional level by sRNAs in R. sphaeroides. Hence, a complex network of different regulatory components controls the defense against photooxidative stress in anoxygenic photosynthetic bacteria.
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Affiliation(s)
- J Glaeser
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität Giessen, Giessen, Germany
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Tamulonis C, Postma M, Kaandorp J. Modeling filamentous cyanobacteria reveals the advantages of long and fast trichomes for optimizing light exposure. PLoS One 2011; 6:e22084. [PMID: 21789215 PMCID: PMC3138769 DOI: 10.1371/journal.pone.0022084] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 06/14/2011] [Indexed: 11/18/2022] Open
Abstract
Cyanobacteria form a very large and diverse phylum of prokaryotes that perform oxygenic photosynthesis. Many species of cyanobacteria live colonially in long trichomes of hundreds to thousands of cells. Of the filamentous species, many are also motile, gliding along their long axis, and display photomovement, by which a trichome modulates its gliding according to the incident light. The latter has been found to play an important role in guiding the trichomes to optimal lighting conditions, which can either inhibit the cells if the incident light is too weak, or damage the cells if too strong. We have developed a computational model for gliding filamentous photophobic cyanobacteria that allows us to perform simulations on the scale of a Petri dish using over 10(5) individual trichomes. Using the model, we quantify the effectiveness of one commonly observed photomovement strategy--photophobic responses--in distributing large populations of trichomes optimally over a light field. The model predicts that the typical observed length and gliding speeds of filamentous cyanobacteria are optimal for the photophobic strategy. Therefore, our results suggest that not just photomovement but also the trichome shape itself improves the ability of the cyanobacteria to optimize their light exposure.
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Affiliation(s)
- Carlos Tamulonis
- Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands.
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Castenholz RW, Jørgensen BB, D'Amelio E, Bauld J. Photosynthetic and behavioral versatility of the cyanobacterium Oscillatoria boryana in a sulfide-rich microbial mat. FEMS Microbiol Ecol 2011. [DOI: 10.1111/j.1574-6941.1991.tb01737.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Garcia-Pichel F, Castenholz RW. Occurrence of UV-Absorbing, Mycosporine-Like Compounds among Cyanobacterial Isolates and an Estimate of Their Screening Capacity. Appl Environ Microbiol 2010; 59:163-9. [PMID: 16348839 PMCID: PMC202072 DOI: 10.1128/aem.59.1.163-169.1993] [Citation(s) in RCA: 314] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A survey of 20 strains of cyanobacteria (belonging to 13 genera) isolated from habitats exposed to strong insolation revealed that 13 strains contained one or more water-soluble, UV-absorbing, mycosporine amino acid (MAA)-like compounds. Some of the compounds were identical in several strains. In all, 13 distinct compounds were found. The UV absorption spectra of MAAs complemented well that of the extracellular sunscreen pigment scytonemin, which many of the strains also produced. Even though the specific MAA contents were variable among strains, they were invariably higher when the cultures were grown with UV radiation than when it was absent. In five strains tested, the MAA complement accumulated as a solute in the cytoplasmic cell fraction. The sunscreen capacities of MAA and scytonemin and their combined capacity were estimated for each strain and condition on the basis of the specific contents, cell size, and cellular location of the compounds. The estimates suggested that significant, albeit not complete, protection from UV photodamage could be gained from the possession of either MAA or scytonemin but especially from simultaneous screening by both types of compounds.
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Affiliation(s)
- F Garcia-Pichel
- Department of Biology, University of Oregon, Eugene, Oregon 97403
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Bebout BM, Garcia-Pichel F. UV B-Induced Vertical Migrations of Cyanobacteria in a Microbial Mat. Appl Environ Microbiol 2010; 61:4215-22. [PMID: 16535178 PMCID: PMC1388643 DOI: 10.1128/aem.61.12.4215-4222.1995] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Exposure to moderate doses of UV B (0.35 to 0.79 W m(sup-2) s(sup-1) or 0.98 to 2.2 (mu)mol of photons m(sup-2) s(sup-1) at 310 nm) caused the surface layers of microbial mats from Solar Lake, Sinai, Egypt, to become visibly lighter green. Concurrent with the color change were rapid and dramatic reductions in gross photosynthesis and in the resultant high porewater oxygen concentrations in the surface layers of the mats. The depths at which both maximum gross photosynthesis and maximum oxygen concentrations occurred were displaced downward. In contrast, gross photosynthesis in the deeper layers of the mats increased in response to UV B incident upon the surface. The cessation of exposure to UV B partially reversed all of these changes. Taken together, these responses suggest that photoautotrophic members of the mat community, most likely the dominant cyanobacterium Microcoleus chthonoplastes, were migrating in response to the added UV B. The migration phenomenon was also observed in response to increases in visible radiation and UV A, but UV B was ca. 100-fold more effective than visible radiation and ca. 20-fold more effective than UV A in provoking the response. Migrating microorganisms within this mat are apparently able to sense UV B directly and respond behaviorally to limit their exposure to UV. Because of strong vertical gradients of light and dissolved substances in microbial mats, the migration and the resultant vertical redistribution of photosynthetic activity have important consequences for both the photobiology of the cyanobacteria and the net primary productivity of the mat ecosystem.
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Richardson LL, Castenholz RW. Chemokinetic Motility Responses of the Cyanobacterium Oscillatoria terebriformis. Appl Environ Microbiol 2010; 55:261-3. [PMID: 16347828 PMCID: PMC184091 DOI: 10.1128/aem.55.1.261-263.1989] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oscillatoria terebriformis, a gliding, filamentous, thermophilic cyanobacterium, exhibited an inhibition of gliding motility upon exposure to fructose. The observed response was transient, and the duration of nonmotility was directly proportional to the concentration of fructose. Upon resumption of motility, the rate of motility was also inversely proportional to the concentration of fructose. Sulfide caused a similar response. The effect of sulfide was specific and not due to either anoxia or negative redox potential. Exposure to glucose, acetate, lactate, or mat interstitial water did not elicit any motility response.
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Affiliation(s)
- L L Richardson
- Department of Biology, University of Oregon, Eugene, Oregon 97403
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23
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Garcia-Pichel F, Mechling M, Castenholz RW. Diel Migrations of Microorganisms within a Benthic, Hypersaline Mat Community. Appl Environ Microbiol 2010; 60:1500-11. [PMID: 16349251 PMCID: PMC201509 DOI: 10.1128/aem.60.5.1500-1511.1994] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We studied the diel migrations of several species of microorganisms in a hypersaline, layered microbial mat. The migrations were quantified by repeated coring of the mat with glass capillary tubes. The resulting minicores were microscopically analyzed by using bright-field and epifluorescence (visible and infrared) microscopy to determine depths of coherent layers and were later dissected to determine direct microscopic counts of microorganisms. Microelectrode measurements of oxygen concentration, fiber optic microprobe measurements of light penetration within the mat, and incident irradiance measurements accompanied the minicore sampling. In addition, pigment content, photosynthesis and irradiance responses, the capacity for anoxygenic photosynthesis, and gliding speeds were determined for the migrating cyanobacteria. Heavily pigmented Oscillatoria sp. and Spirulina cf. subsalsa migrated downward into the mat during the early morning and remained deep until dusk, when upward migration occurred. The mean depth of the migration (not more than 0.4 to 0.5 mm) was directly correlated with the incident irradiance over the mat surface. We estimated that light intensity at the upper boundary of the migrating cyanobacteria was attenuated to such an extent that photoinhibition was effectively avoided but that intensities which saturated photosynthesis were maintained through most of the daylight hours. Light was a cue of paramount importance in triggering and modulating the migration of the cyanobacteria, even though the migrating phenomenon could not be explained solely in terms of a light response. We failed to detect diel migration patterns for other cyanobacterial species and filamentous anoxyphotobacteria. The sulfide-oxidizing bacterium Beggiatoa sp. migrated as a band that followed low oxygen concentrations within the mat during daylight hours. During the nighttime, part of this population migrated toward the mat surface, but a significant proportion remained deep.
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Affiliation(s)
- F Garcia-Pichel
- Department of Biology, University of Oregon, Eugene, Oregon 97403
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24
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Kohls K, Abed RMM, Polerecky L, Weber M, de Beer D. Halotaxis of cyanobacteria in an intertidal hypersaline microbial mat. Environ Microbiol 2009; 12:567-75. [PMID: 19919535 DOI: 10.1111/j.1462-2920.2009.02095.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An intertidal hypersaline cyanobacterial mat from Abu Dhabi (United Arab Emirates) exhibited a reversible change in its surface colour within several hours upon changes in salinity of the overlying water. The mat surface was orange-reddish at salinities above 15% and turned dark green at lower salinities. We investigated this phenomenon using a polyphasic approach that included denaturing gradient gel electrophoresis, microscopy, high-performance liquid chromatography, hyperspectral imaging, absorption spectroscopy, oxygen microsensor measurements and modelling of salinity dynamics. Filaments of Microcoleus chthonoplastes, identified based on 16S rRNA sequencing and morphology, were found to migrate up and down when salinity was decreased below or increased above 15%, respectively, causing the colour change of the mat uppermost layer. Migration occurred in light and in the dark, and could be induced by different salts, not only NaCl. The influence of salinity-dependent and independent physico-chemical parameters, such as water activity, oxygen solubility, H2S, gravity and light, was excluded, indicating that the observed migration was due to a direct response to salt stress. We propose to term this salinity-driven cyanobacterial migration as 'halotaxis', a process that might play a vital role in the survival of cyanobacteria in environments exposed to continuous salinity fluctuations such as intertidal flats.
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Affiliation(s)
- Katharina Kohls
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany.
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25
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Myers JL, Richardson LL. Adaptation of cyanobacteria to the sulfide-rich microenvironment of black band disease of coral. FEMS Microbiol Ecol 2008; 67:242-51. [PMID: 19049501 DOI: 10.1111/j.1574-6941.2008.00619.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Black band disease (BBD) is a cyanobacteria-dominated microbial mat that migrates across living coral colonies lysing coral tissue and leaving behind exposed coral skeleton. The mat is sulfide-rich due to the presence of sulfate-reducing bacteria, integral members of the BBD microbial community, and the sulfide they produce is lethal to corals. The effect of sulfide, normally toxic to cyanobacteria, on the photosynthetic capabilities of five BBD cyanobacterial isolates of the genera Geitlerinema (3), Leptolyngbya (1), and Oscillatoria (1) and six non-BBD cyanobacteria of the genera Leptolyngbya (3), Pseudanabaena (2), and Phormidium (1) was examined. Photosynthetic experiments were performed by measuring the photoincorporation of [(14)C] NaHCO(3) under the following conditions: (1) aerobic (no sulfide), (2) anaerobic with 0.5 mM sulfide, and (3) anaerobic with 0.5 mM sulfide and 10 microM 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU). All five BBD cyanobacterial isolates tolerated sulfide by conducting sulfide-resistant oxygenic photosynthesis. Five of the non-BBD cyanobacterial isolates did not tolerate sulfide, although one Pseudanabaena isolate continued to photosynthesize in the presence of sulfide at a considerably reduced rate. None of the isolates conducted anoxygenic photosynthesis with sulfide as an electron donor. This is the first report on the physiology of a culture of Oscillatoria sp. found globally in BBD.
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Affiliation(s)
- Jamie L Myers
- Department of Biological Sciences, Florida International University, Miami, FL 33177, USA.
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Hinck S, Neu TR, Lavik G, Mussmann M, de Beer D, Jonkers HM. Physiological adaptation of a nitrate-storing Beggiatoa sp. to diel cycling in a phototrophic hypersaline mat. Appl Environ Microbiol 2007; 73:7013-22. [PMID: 17766448 PMCID: PMC2074952 DOI: 10.1128/aem.00548-07] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to investigate the supposed vertical diel migration and the accompanying physiology of Beggiatoa bacteria from hypersaline microbial mats. We combined microsensor, stable-isotope, and molecular techniques to clarify the phylogeny and physiology of the most dominant species inhabiting mats of the natural hypersaline Lake Chiprana, Spain. The most dominant morphotype had a filament diameter of 6 to 8 microm and a length varying from 1 to >10 mm. Phylogenetic analysis by 16S rRNA gene comparison revealed that this type appeared to be most closely related (91% sequence identity) to the narrow (4-microm diameter) nonvacuolated marine strain MS-81-6. Stable-isotope analysis showed that the Lake Chiprana species could store nitrate intracellularly to 40 mM. The presence of large intracellular vacuoles was confirmed by fluorescein isothiocyanate staining and subsequent confocal microscopy. In illuminated mats, their highest abundance was found at a depth of 8 mm, where oxygen and sulfide co-occurred. However, in the dark, the highest Beggiatoa densities occurred at 7 mm, and the whole population was present in the anoxic zone of the mat. Our findings suggest that hypersaline Beggiatoa bacteria oxidize sulfide with oxygen under light conditions and with internally stored nitrate under dark conditions. It was concluded that nitrate storage by Beggiatoa is an optimal strategy to both occupy the suboxic zones in sulfidic sediments and survive the dark periods in phototrophic mats.
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Affiliation(s)
- Susanne Hinck
- Max Planck Institute for Marine Microbiology, Celsiusstr. 1, D-28359 Bremen, Germany.
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Fourçans A, Solé A, Diestra E, Ranchou-Peyruse A, Esteve I, Caumette P, Duran R. Vertical migration of phototrophic bacterial populations in a hypersaline microbial mat from Salins-de-Giraud (Camargue, France). FEMS Microbiol Ecol 2006; 57:367-77. [PMID: 16907751 DOI: 10.1111/j.1574-6941.2006.00124.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The spatio-temporal distribution of phototrophic communities of the hypersaline photosynthetic Camarguc microbial mat (Salins-de-Giraud, France) was investigated over a diel cycle by combining microscopic and molecular approaches. Microcoleus chthonoplastes and Halomicronema excentricum, the dominant cyanobacteria of this oxyphotrophic community, were observed with confocal laser scanning microscopy to determine their biomass profiles. Both bacteria have similar vertical distributions, varying from a homogenous distribution through the mat during the night, to a specific localization in the upper oxic zone of 1.5 mm during the day. Terminal restriction fragment length polymorphism of PCR-amplified pufM gene fragments revealed three groups of anoxyphototrophic populations, which varied according to the two opposite periods of the diel cycle under study. They were either specifically detected in only one period, or homogenously distributed through the mat in all periods, or located in specific zones of the mat depending on the period considered. Oxygen concentrations, pH and biomass of the major filamentous cyanobacteria were the determinative factors in the distribution of these anoxyphototrophs across the mat. Thus, vertical migration, cell-cell aggregate formation and metabolic switches were the most evident defence of the photosynthetic populations against the adverse effects of sulfide and oxygen fluxes during a diel cycle.
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Affiliation(s)
- Aude Fourçans
- Laboratoire d'Ecologie Moléculaire EA 3525, Université de Pau et des Pays de l'Adour, avenue de l'Université, BP 1155, Pau Cedex, France
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Richardson LL, Kuta KG. Ecological physiology of the black band disease cyanobacterium Phormidium corallyticum. FEMS Microbiol Ecol 2003; 43:287-98. [DOI: 10.1016/s0168-6496(03)00025-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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31
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Shi X, Yang L, Niu X, Xiao L, Kong Z, Qin B, Gao G. Intracellular phosphorus metabolism of Microcystis aeruginosa under various redox potential in darkness. Microbiol Res 2003; 158:345-52. [PMID: 14717456 DOI: 10.1078/0944-5013-00214] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Phosphorus metabolism of Microcystis aeruginosa was studied under gradient redox potential from 252 mV to -70 mV in darkness. The release of phosphorus occurred in all the treatments, and this process was accelerated in darkness when the redox potential was lowered. Low redox potential in darkness stimulated the accumulation of polyphosphate (PolyP) and the degradation of polyglucose. The synthesis of PolyP delayed the decrease of intracellular orthophosphate. The death of M. aeruginosa was slowered when the redox potential was low in darkness. The accumulation of PolyP under low redox potential in the dark was very important to M. aeruginosa for endurance through the unfavorable growth conditions for maintaining phosphorus concentration, energy storage, and other physiological functions. The ability to accumulate PolyP in the dark and negative redox potential may be of considerable advantage in the low-light, organically rich, and low-redox habitats.
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Affiliation(s)
- Xiaoli Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China
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33
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Kruschel C, Castenholz RW. The effect of solar UV and visible irradiance on the vertical movements of cyanobacteria in microbial mats of hypersaline waters. FEMS Microbiol Ecol 1998. [DOI: 10.1111/j.1574-6941.1998.tb00525.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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34
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Richardson LL. Horizontal and Vertical Migration Patterns of Phormidium corallyticum and Beggiatoa spp. Associated with Black-Band Disease of Corals. MICROBIAL ECOLOGY 1996; 32:323-35. [PMID: 8849426 DOI: 10.1007/bf00183066] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
An in situ field study of the motility patterns exhibited by Phormidium corallyticum and Beggiatoa spp. in black-band disease of corals was conducted over a 5-day period. Measurements were made at a spatial resolution of 50 &mgr;m to document the horizontal migration of black-band across living coral tissue, while vertical migrations within the band were documented by observation and macrophotography of the black-band surface. It was determined that horizontal migration occurred both day and night, with the fastest movements by the front of the band during the day and the back of the band at night. Beggiatoa would rise to the band surface at night, and would often remain above the cyanobacterial population during extended periods of illumination the following day. The migration patterns are discussed in terms of motility cues and microbial physiology.
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Affiliation(s)
- LL Richardson
- Department of Biological Sciences and Drinking Water Research Center, Florida International University, Miami, Florida 33199, USA
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35
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Carlton RG, Richardson LL. Oxygen and sulfide dynamics in a horizontally migrating cyanobacterial mat: Black band disease of corals. FEMS Microbiol Ecol 1995. [DOI: 10.1111/j.1574-6941.1995.tb00173.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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36
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Stal LJ. Physiological ecology of cyanobacteria in microbial mats and other communities. THE NEW PHYTOLOGIST 1995; 131:1-32. [PMID: 33863161 DOI: 10.1111/j.1469-8137.1995.tb03051.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this review some aspects of the physiological ecology of cyanobacteria are discussed by taking a microbial mat as an example. The majority of microbial mats are built and dominated by cyarsobacteria which are primary producers at the basis of the microbial foodweb in microbial mats. These micro-scale ecosystems are characterized by steep and fluctuating physico-chemical gradients of which those of light, oxygen and sulphide are the most conspicuous. Light is strongly attenuated in the sediment, and owing to constant sedimentation, the mat-forming cyanobacteria have to move upwards towards the light. However, at the sediment surface, light intensity, particularly in the u.v. part of the spectrum, is often deleterious. The gliding movement of the cyanobacteria, with photo- and chemotaxis, allows the organism to position itself in a thin layer at optimal conditions. The organic matter produced by cyanobacterial photosynthesis is decomposed by the ruicrobial community. Sulphate-reducing bacteria are important in the end-oxidation of the organic matter. These organisms are obligate anaerobes and produce sulphide. Gradients of sulphide and oxygen move up and down in the sediment as a response to diurnal variations of light intensity. Cyanobacteria, therefore, are sometimes exposed to large concentrations of the extremely toxic sulphide. Some species are capable of sulphide-dependent anoxygenic photosynthesis. Other cyanobacteria show increased rates of oxygenic photosynthesis in the presence of sulphide and have mechanisms to oxidize sulphide while avoiding sulphide toxicity. Iron might play an important role in this process. Under anoxic conditions in the dark, mat-forming cyanobacteria switch to fermentative metabolism. Many species are also capable of fermentative reduction of elemental sulphur to sulphide. The gradients of sulphide and oxygen are of particular importance for nitrogen fixation. Very few microbial mats are formed by heterocystous cyanobacteria, which are best adapted to diazntrophic growth. However, these organisms probably cannot tolerate greater concentrations of sulphide or anoxic conditions or both. Under such conditions non-heterocystous cyanobacteria become dominant as diazotrophs. These organisms avoid conditions of oxygen supersaturation. In the ecosystem, nitrogen fixation and photosynthesis might be separated temporally as well as spatially. In addition, non-heterocystous diazotrophic cyanobacteria have mechanisms at the subcellular level to protect the oxygen-sensitive nitrogenase from inaction. CONTENTS Summary 1 I. Introduction 2 II. Microbial mats 3 III. Cyanobacteria in light gradients 7 IV. Dark metabolism 10 V. Interactions with sulphide 13 VI. Nitrogen fixation 16 VII. References 28.
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Affiliation(s)
- Lucas J Stal
- Laboratory for Microbiology, University of Amsterdam, Nieuwe Achtergracht 127, NL-1018 WS Amsterdam, The Netherlands
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Castenholz R, Jørgensen B, D'Amelio E, Bauld J. Photosynthetic and behavioral versatility of the cyanobacteriumOscillatoira boryanain a sulfide-rich microbial mat. FEMS Microbiol Lett 1991. [DOI: 10.1111/j.1574-6968.1991.tb04794.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Willey JM, Waterbury JB. Chemotaxis toward Nitrogenous Compounds by Swimming Strains of Marine Synechococcus spp. Appl Environ Microbiol 1989; 55:1888-1894. [PMID: 16347985 PMCID: PMC202974 DOI: 10.1128/aem.55.8.1888-1894.1989] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Many of the open-ocean isolates of the marine unicellular cyanobacterium Synechococcus spp. are capable of swimming motility, whereas coastal isolates are nonmotile. Surprisingly, the motile strains do not display phototactic or photophobic responses to light, but they do demonstrate positive chemoresponses to several nitrogenous compounds. The chemotactic responses of Synechococcus strain WH8113 were investigated using blind-well chemotaxis chambers fitted with 3.0-mum-pore-size Nuclepore filters. One well of each chamber contained cells suspended in aged Sargasso Sea water, and the other well contained the potential chemoattractant in seawater. The number of cells that crossed the filter into the attractant-seawater mixture was measured by direct cell counts and compared with values obtained in chambers lacking gradients. Twenty-two compounds were tested, including sugars, amino acids, and simple nitrogenous substrates, at concentrations ranging from 10 to 10 M. Strain WH8113 responded positively only to ammonia, nitrate, beta-alanine, glycine, and urea. Typically, there was a 1.5- to 2-fold increase in cell concentrations above control levels in chambers containing these compounds, which is comparable to results from similar experiments using enteric and photoheterotrophic bacteria. However, the threshold levels of 10 to 10 M found for Synechococcus spp. chemoresponses were lower by several orders of magnitude than those reported for other bacteria and fell within a range that could be ecologically significant in the oligotrophic oceans. The presence of chemotaxis in motile Synechococcus spp. supports the notion that regions of nutrient enrichment, such as the proposed microzones and patches, may play an important role in picoplankton nutrient dynamics.
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Affiliation(s)
- J M Willey
- Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543
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Jørgensen BB, Cohen Y, Revsbech NP. Photosynthetic Potential and Light-Dependent Oxygen Consumption in a Benthic Cyanobacterial Mat. Appl Environ Microbiol 1988; 54:176-182. [PMID: 16347523 PMCID: PMC202418 DOI: 10.1128/aem.54.1.176-182.1988] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The potential to carry out oxygenic photosynthesis after prolonged burial below the photic zone was studied at 0.1-mm depth intervals in the thick, laminated
Microcoleus chthonoplastes
mats growing in Solar Lake, Sinai. The buried mat community lost about 20% of its photosynthetic potential with depth per annual layer down to 8- to 10-year-old layers at a 14-mm depth. In some of the older layers, below a 30-mm depth, light-dependent oxygen consumption which increased with increasing light intensity was observed. Possible mechanisms for this phenomenon are (i) pseudocyclic electron transport (Mehler reaction), (ii) interactions between respiratory electron transport and photosynthetic electron transport, (iii) photorespiration, and (iv) photooxidation.
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Richardson LL, Castenholz RW. Enhanced Survival of the Cyanobacterium
Oscillatoria terebriformis
in Darkness under Anaerobic Conditions. Appl Environ Microbiol 1987; 53:2151-8. [PMID: 16347436 PMCID: PMC204073 DOI: 10.1128/aem.53.9.2151-2158.1987] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oscillatoria terebriformis
, a thermophilic cyanobacterium, maintained viability in darkness under anaerobic conditions by fermenting exogenous glucose or fructose to lactic acid. The time period of survival was greatly extended when the environmental redox potential was lowered by the addition of sodium thioglycolate or titanium(III) citrate. When exposed to aerobic conditions in darkness, many trichomes underwent lysis in 6 h, and death of all cells occurred in 2 to 3 days. The endogenous aerobic respiration rate was high, and the limited dark aerobic survival period appeared to be due to depletion of stored glycogen. Fructose or glucose did not support or increase aerobic respiration in darkness or lengthen aerobic survival time. Enhanced survival of
O. terebriformis
in darkness under anaerobic, reducing conditions correlates well with the natural nighttime position of this species within sulfide-rich microbial mats associated with hot springs of western North America.
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Affiliation(s)
- L L Richardson
- Department of Biology, University of Oregon, Eugene, Oregon 97403
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