1
|
Klemanska A, Dwyer K, Walsh G. Truncation of a novel C-terminal domain of a β-glucanase improves its thermal stability and specific activity. Biotechnol J 2024; 19:e2400245. [PMID: 39118577 DOI: 10.1002/biot.202400245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 06/10/2024] [Accepted: 06/28/2024] [Indexed: 08/10/2024]
Abstract
Enzymes that degrade β-glucan play important roles in various industries, including those related to brewing, animal feed, and health care. Csph16A, an endo-β-1,3(4)-glucanase encoded by a gene from the halotolerant, xerotolerant, and radiotrophic black fungus Cladosporium sphaerospermum, was cloned and expressed in Pichia pastoris. Two isoforms (Csph16A.1 and Csph16A.2) are produced, arising from differential glycosylation. The proteins were predicted to contain a catalytic Lam16A domain, along with a C-terminal domain (CTD) of unknown function which exhibits minimal secondary structure. Employing PCR-mediated gene truncation, the CTD of Csph16A was excised to assess its functional impact on the enzyme and determine potential alterations in biotechnologically relevant characteristics. The truncated mutant, Csph16A-ΔC, exhibited significantly enhanced thermal stability at 50°C, with D-values 14.8 and 23.5 times greater than those of Csph16A.1 and Csph16A.2, respectively. Moreover, Csph16A-ΔC demonstrated a 20%-25% increase in halotolerance at 1.25 and 1.5 M NaCl, respectively, compared to the full-length enzymes. Notably, specific activity against cereal β-glucan, lichenan, and curdlan was increased by up to 238%. This study represents the first characterization of a glucanase from the stress-tolerant fungus C. sphaerospermum and the first report of a halotolerant and engineered endo-β-1,3(4)-glucanase. Additionally, it sheds light on a group of endo-β-1,3(4)-glucanases from Antarctic rock-inhabiting black fungi harboring a Lam16A catalytic domain and a novel CTD of unknown function.
Collapse
Affiliation(s)
- Anastasia Klemanska
- Department of Chemical Sciences & Bernal Institute, University of Limerick, Castletroy, Limerick City, Ireland
- Monaghan Mushrooms, Tyholland, Co, Monaghan, Ireland
| | - Kelly Dwyer
- Monaghan Mushrooms, Tyholland, Co, Monaghan, Ireland
| | - Gary Walsh
- Department of Chemical Sciences & Bernal Institute, University of Limerick, Castletroy, Limerick City, Ireland
| |
Collapse
|
2
|
Lorenz C, Bianchi E, Poggiali G, Alemanno G, Benesperi R, Brucato JR, Garland S, Helbert J, Loppi S, Lorek A, Maturilli A, Papini A, de Vera JP, Baqué M. Survivability of the lichen Xanthoria parietina in simulated Martian environmental conditions. Sci Rep 2023; 13:4893. [PMID: 36966209 PMCID: PMC10039903 DOI: 10.1038/s41598-023-32008-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/21/2023] [Indexed: 03/27/2023] Open
Abstract
Xanthoria parietina (L.) Th. Fr. is a widely spread foliose lichen showing high tolerance against UV-radiation thanks to parietin, a secondary lichen substance. We exposed samples of X. parietina under simulated Martian conditions for 30 days to explore its survivability. The lichen's vitality was monitored via chlorophyll a fluorescence that gives an indication for active light reaction of photosynthesis, performing in situ and after-treatment analyses. Raman spectroscopy and TEM were used to evaluate carotenoid preservation and possible variations in the photobiont's ultrastructure respectively. Significant differences in the photo-efficiency between UV irradiated samples and dark-kept samples were observed. Fluorescence values correlated with temperature and humidity day-night cycles. The photo-efficiency recovery showed that UV irradiation caused significant effects on the photosynthetic light reaction. Raman spectroscopy showed that the carotenoid signal from UV exposed samples decreased significantly after the exposure. TEM observations confirmed that UV exposed samples were the most affected by the treatment, showing chloroplastidial disorganization in photobionts' cells. Overall, X. parietina was able to survive the simulated Mars conditions, and for this reason it may be considered as a candidate for space long-term space exposure and evaluations of the parietin photodegradability.
Collapse
Affiliation(s)
- Christian Lorenz
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Elisabetta Bianchi
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Giovanni Poggiali
- LESIA-Observatoire de Paris, CNRS, Université PSL, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, 92190, Meudon, France
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125, Florence, Italy
| | - Giulia Alemanno
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Renato Benesperi
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - John Robert Brucato
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125, Florence, Italy.
| | - Stephen Garland
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Jörn Helbert
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Stefano Loppi
- Department of Environmental Sciences, University of Siena, Via P. A. Mattioli 4, 53100, Siena, Italy
| | - Andreas Lorek
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Alessandro Maturilli
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Alessio Papini
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Jean-Pierre de Vera
- Microgravity User Support Center (MUSC), Space Operations and Astronaut Training, German Aerospace Center (DLR), Linder Höhe, 51147, Cologne, Germany
| | - Mickaël Baqué
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| |
Collapse
|
3
|
Nikitin DA. Ecological Characteristics of Antarctic Fungi. DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2023; 508:32-54. [PMID: 37186046 DOI: 10.1134/s0012496622700120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 09/15/2022] [Accepted: 09/15/2022] [Indexed: 05/17/2023]
Abstract
In view of the high responsiveness of polar ecosystems to the global climate change, the research of Antarctic microorganisms has become a topical issue. The unique ecosystems that have developed under the severe climate conditions of the continent lack flowering plants but are dominated by soil mycobiota. In addition to performing their classical ecological functions, Antarctic fungi form the basis of local communities, e.g., endoliths and microbial mats. Furthermore, Antarctic fungi are a major force that mediates transformation of rock minerals in situ and makes biologically significant elements available for other organisms. For these reasons, mycobiota plays a central role in the maintenance of ecological equilibrium in Antarctica. The dominant fungal division on the continent is Ascomycota (77.1%), and not Basidiomycota (9.1%), as it is the case on other continents. For a number of reasons, yeasts and yeast-like micromycetes (mainly basidiomycetes) are more tolerant to extreme conditions in various Antarctic biotopes than filamentous fungi. Substantial evidence suggests that filamentous fungi and yeasts are better adapted to existence in ecosystems with extremely low temperatures than other microorganisms. Due to the long-term isolation of Antarctica from other continents, local biota has been evolving largely independently, which led to emergence of multiple endemic fungal taxa. The presence of eurytopes on the continent is presumably related to the global warming and growing anthropogenic pressure. This review discusses the current state of research on the structure of fungal communities of Antarctic subaerial and subaquatic biotopes, the ecological role of yeast-mycelial dimorphism in Antarctic fungi, the problem of endemism of Antarctic mycobiota, as well as the ecological and physiological adaptations of fungi to low temperatures; it also justifies the relevance of research into secondary metabolites of psychrophilic micromycetes.
Collapse
Affiliation(s)
- D A Nikitin
- Dokuchaev Soil Science Institute, 119017, Moscow, Russia.
- Institute of Geography, Russian Academy of Sciences, 119017, Moscow, Russia.
| |
Collapse
|
4
|
Perliński P, Mudryk ZJ, Zdanowicz M, Kubera Ł. Abundance of Live and Dead Bacteriopsammon Inhabiting Sandy Ecosystems of Recreational Marine Beaches of the Southern Baltic Sea. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02079-5. [PMID: 35876854 DOI: 10.1007/s00248-022-02079-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
The study was carried out on four non-tidal sandy marine beaches located on the Polish part of the southern Baltic Sea coast. We applied a LIVE/DEAD™ BacLight™ Bacterial Viability Kit (Invitrogen™) method to determine the abundance of live and dead bacteriopsammon. Live psammon bacteria cells constituted 31-53% of the total number of bacteria inhabiting sand of the studied beaches. Abundance of live and dead psammon bacteria generally differed along the horizontal profile in all beaches. The maximum density of bacteria was noted in the dune and the middle part of the beach (dry zones) and the minimum in wet zones, i.e., under seawater surface and at the swash zone. Generally along the vertical profile, the highest numbers of two studied bacterial groups were noted in the surface sand layer, while with increasing sediment depth their numbers significantly decreased. The abundance of live and dead bacteria showed a distinct seasonal variation.
Collapse
Affiliation(s)
- Piotr Perliński
- Department of Experimental Biology, Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, Arciszewskiego 22B str, 76-200, Słupsk, Poland.
| | - Zbigniew Jan Mudryk
- Department of Experimental Biology, Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, Arciszewskiego 22B str, 76-200, Słupsk, Poland
| | - Marta Zdanowicz
- Department of Experimental Biology, Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, Arciszewskiego 22B str, 76-200, Słupsk, Poland
| | - Łukasz Kubera
- Department of Microbiology and Immunobiology, Faculty of Biological Sciences, Kazimierz Wielki University, Al. Powstańców Wielkopolskich 10, 85-090, Bydgoszcz, Poland
| |
Collapse
|
5
|
Coleine C, Stajich JE, de Los Ríos A, Selbmann L. Beyond the extremes: Rocks as ultimate refuge for fungi in drylands. Mycologia 2020; 113:108-133. [PMID: 33232202 DOI: 10.1080/00275514.2020.1816761] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In an era of rapid climate change and expansion of desertification, the extremely harsh conditions of drylands are a true challenge for microbial life. Under drought conditions, where most life forms cannot survive, rocks represent the main refuge for life. Indeed, the endolithic habitat provides thermal buffering, physical stability, and protection against incident ultraviolet (UV) radiation and solar radiation and, to some extent, ensures water retention to microorganisms. The study of these highly specialized extreme-tolerant and extremophiles may provide tools for understanding microbial interactions and processes that allow them to keep their metabolic machinery active under conditions of dryness and oligotrophy that are typically incompatible with active life, up to the dry limits for life. Despite lithobiontic communities being studied all over the world, a comprehensive understanding of their ecology, evolution, and adaptation is still nascent. Herein, we survey the fungal component of these microbial ecosystems. We first provide an overview of the main defined groups (i.e., lichen-forming fungi, black fungi, and yeasts) of the most known and studied Antarctic endolithic communities that are almost the only life forms ensuring ecosystem functionality in the ice-free areas of the continent. For each group, we discuss their main traits and their diversity. Then, we focus on the fungal taxonomy and ecology of other worldwide endolithic communities. Finally, we highlight the utmost importance of a global rock survey in order to have a comprehensive view of the diversity, distribution, and functionality of these fungi in drylands, to obtain tools in desert area management, and as early alarm systems to climate change.
Collapse
Affiliation(s)
- Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia , Largo dell'Università snc, 01100, Viterbo, Italy
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, University of California, 900 University Ave , Riverside, California 92521
| | - Asunción de Los Ríos
- Department of Biogeochemistry and Microbial Ecology, Museo Nacional de Ciencias Naturales, Spanish National Resource Council, Madrid, Spain
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia , Largo dell'Università snc, 01100, Viterbo, Italy.,Italian National Antarctic Museum, Mycological Section, Genoa, Italy
| |
Collapse
|
6
|
Valenzuela MV, Domenech M, Mateos-Martínez P, González-Camacho F, de la Campa AG, García MT. Antibacterial activity of a DNA topoisomerase I inhibitor versus fluoroquinolones in Streptococcus pneumoniae. PLoS One 2020; 15:e0241780. [PMID: 33141832 PMCID: PMC7608930 DOI: 10.1371/journal.pone.0241780] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 10/20/2020] [Indexed: 12/23/2022] Open
Abstract
The DNA topoisomerase complement of Streptococcus pneumoniae is constituted by two type II enzymes (topoisomerase IV and gyrase), and a single type I enzyme (topoisomerase I). These enzymes maintain the DNA topology, which is essential for replication and transcription. While fluoroquinolones target the type II enzymes, seconeolitsine, a new antimicrobial agent, targets topoisomerase I. We compared for the first time the in vitro effect of inhibition of topoisomerase I by seconeolitsine and of the type II topoisomerases by the fluoroquinolones levofloxacin and moxifloxacin. We used three isogenic non-encapsulated strains and five non-vaccine serotypes isolates belonging to two circulating pneumococcal clones, ST638 (2 strains) and ST1569V (3 strains). Each group contained strains with diverse susceptibility to fluoroquinolones. Minimal inhibitory concentrations, killing curves and postantibiotic effects were determined. Seconeolitsine demonstrated the fastest and highest bactericidal activity against planktonic bacteria and biofilms. When fluoroquinolone-susceptible planktonic bacteria were considered, seconeolitsine induced postantibiotic effects (1.00−1.87 h) similar than levofloxacin (1.00−2.22 h), but longer than moxifloxacin (0.39−1.71 h). The same effect was observed in sessile bacteria forming biofilms. Seconeolitsine induced postantibiotic effects (0.84−2.31 h) that were similar to those of levofloxacin (0.99−3.32 h) but longer than those of moxifloxacin (0.89−1.91 h). The greatest effect was observed in the viability and adherence of bacteria in the postantibiotic phase. Seconeolitsine greatly reduced the thickness of the biofilms formed in comparison with fluoroquinolones: 2.91 ± 0.43 μm (seconeolitsine), 7.18 ± 0.58 μm (levofloxacin), 17.08 ± 1.02 μm (moxifloxacin). When fluoroquinolone-resistant bacteria were considered, postantibiotic effects induced by levofloxacin and moxifloxacin, but not by seconeolitsine, were shorter, decreasing up to 5-fold (levofloxacin) or 2-fold (moxifloxacin) in planktonic cells, and up to 1.7 (levofloxacin) or 1.4-fold (moxifloxacin) during biofilm formation. Therefore, topoisomerase I inhibitors could be an alternative for the treatment of pneumococcal diseases, including those caused by fluoroquinolone-resistant isolates.
Collapse
Affiliation(s)
- Myriam V. Valenzuela
- Departamento de Genética, Unidad de Microbiología, Fisiología y Microbiología, Universidad Complutense, Madrid, Spain
| | - Mirian Domenech
- Unidad de Neumococos, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid; Spain
| | - Patricia Mateos-Martínez
- Departamento de Genética, Unidad de Microbiología, Fisiología y Microbiología, Universidad Complutense, Madrid, Spain
| | - Fernando González-Camacho
- Unidad de Neumococos, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid; Spain
| | - Adela G. de la Campa
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid; Spain
- Presidencia, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- * E-mail: (MTG); (AGC)
| | - Maria Teresa García
- Departamento de Genética, Unidad de Microbiología, Fisiología y Microbiología, Universidad Complutense, Madrid, Spain
- * E-mail: (MTG); (AGC)
| |
Collapse
|
7
|
Bezuidt OKI, Lebre PH, Pierneef R, León-Sobrino C, Adriaenssens EM, Cowan DA, Van de Peer Y, Makhalanyane TP. Phages Actively Challenge Niche Communities in Antarctic Soils. mSystems 2020; 5:e00234-20. [PMID: 32371471 PMCID: PMC7205518 DOI: 10.1128/msystems.00234-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 04/06/2020] [Indexed: 12/22/2022] Open
Abstract
By modulating the structure, diversity, and trophic outputs of microbial communities, phages play crucial roles in many biomes. In oligotrophic polar deserts, the effects of katabatic winds, constrained nutrients, and low water availability are known to limit microbial activity. Although phages may substantially govern trophic interactions in cold deserts, relatively little is known regarding the precise ecological mechanisms. Here, we provide the first evidence of widespread antiphage innate immunity in Antarctic environments using metagenomic sequence data from hypolith communities as model systems. In particular, immunity systems such as DISARM and BREX are shown to be dominant systems in these communities. Additionally, we show a direct correlation between the CRISPR-Cas adaptive immunity and the metavirome of hypolith communities, suggesting the existence of dynamic host-phage interactions. In addition to providing the first exploration of immune systems in cold deserts, our results suggest that phages actively challenge niche communities in Antarctic polar deserts. We provide evidence suggesting that the regulatory role played by phages in this system is an important determinant of bacterial host interactions in this environment.IMPORTANCE In Antarctic environments, the combination of both abiotic and biotic stressors results in simple trophic levels dominated by microbiomes. Although the past two decades have revealed substantial insights regarding the diversity and structure of microbiomes, we lack mechanistic insights regarding community interactions and how phages may affect these. By providing the first evidence of widespread antiphage innate immunity, we shed light on phage-host dynamics in Antarctic niche communities. Our analyses reveal several antiphage defense systems, including DISARM and BREX, which appear to dominate in cold desert niche communities. In contrast, our analyses revealed that genes which encode antiphage adaptive immunity were underrepresented in these communities, suggesting lower infection frequencies in cold edaphic environments. We propose that by actively challenging niche communities, phages play crucial roles in the diversification of Antarctic communities.
Collapse
Affiliation(s)
- Oliver K I Bezuidt
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Pedro Humberto Lebre
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Rian Pierneef
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Biotechnology Platform, Agricultural Research Council, Pretoria, South Africa
| | - Carlos León-Sobrino
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | | | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Yves Van de Peer
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Thulani P Makhalanyane
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
8
|
Jasser I, Kostrzewska-Szlakowska I, Kwiatowski J, Navruzshoev D, Suska-Malawska M, Khomutovska N. Morphological and Molecular Diversity of Benthic Cyanobacteria Communities Versus Environmental Conditions in Shallow, High Mountain Water Bodies in Eastern Pamir Mountains (Tajikistan). POLISH JOURNAL OF ECOLOGY 2020. [DOI: 10.3161/15052249pje2019.67.4.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Iwona Jasser
- University of Warsaw, Department of Plant Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, Żwirki i Wigury 101, 02–089 Warszawa, Poland
| | | | - Jan Kwiatowski
- University of Warsaw, Faculty of Biology, Miecznikowa 1, 02–089, Warszawa, Poland
| | - Dovutsho Navruzshoev
- Kh.Yu. Yusufbekov Pamir Biological Institute of the Academy of Sciences of the Republic of Tajikistan, Khorog, Tajikistan
| | - Małgorzata Suska-Malawska
- University of Warsaw, Department of Plant Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, Żwirki i Wigury 101, 02–089 Warszawa, Poland
| | - Nataliia Khomutovska
- University of Warsaw, Department of Plant Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, Żwirki i Wigury 101, 02–089 Warszawa, Poland
| |
Collapse
|
9
|
Coleine C, Stajich JE, Pombubpa N, Zucconi L, Onofri S, Canini F, Selbmann L. Altitude and fungal diversity influence the structure of Antarctic cryptoendolithic Bacteria communities. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:718-726. [PMID: 31393667 PMCID: PMC8057506 DOI: 10.1111/1758-2229.12788] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 08/04/2019] [Accepted: 08/05/2019] [Indexed: 05/11/2023]
Abstract
Endolithic growth within rocks is a critical adaptation of microbes living in harsh environments where exposure to extreme temperature, radiation, and desiccation limits the predominant life forms, such as in the ice-free regions of Continental Antarctica. The microbial diversity of the endolithic communities in these areas has been sparsely examined. In this work, diversity and composition of bacterial assemblages in the cryptoendolithic lichen-dominated communities of Victoria Land (Continental Antarctica) were explored using a high-throughput metabarcoding approach, targeting the V4 region of 16S rDNA. Rocks were collected in 12 different localities (from 14 different sites), along a gradient ranging from 1000 to 3300 m a.s.l. and at a sea distance ranging from 29 to 96 km. The results indicate Actinobacteria and Proteobacteria are the dominant taxa in all samples and defined a 'core' group of bacterial taxa across all sites. The structure of bacteria communities is correlated with the fungal counterpart and among the environmental parameters considered, altitude was found to influence bacterial biodiversity, while distance from sea had no evident influence.
Collapse
Affiliation(s)
- Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Jason E. Stajich
- Department of Microbiology and Plant Pathology and Institute of Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Nuttapon Pombubpa
- Department of Microbiology and Plant Pathology and Institute of Integrative Genome Biology, University of California, Riverside, CA, USA
| | - Laura Zucconi
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Silvano Onofri
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Fabiana Canini
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
- Italian Antarctic National Museum (MNA), Mycological Section, Genoa, Italy
| |
Collapse
|
10
|
Meslier V, Casero MC, Dailey M, Wierzchos J, Ascaso C, Artieda O, McCullough PR, DiRuggiero J. Fundamental drivers for endolithic microbial community assemblies in the hyperarid Atacama Desert. Environ Microbiol 2018; 20:1765-1781. [DOI: 10.1111/1462-2920.14106] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 03/15/2018] [Indexed: 11/30/2022]
Affiliation(s)
- Victoria Meslier
- Department of BiologyThe Johns Hopkins UniversityBaltimore MD USA
| | | | - Micah Dailey
- Department of BiologyThe Johns Hopkins UniversityBaltimore MD USA
| | | | - Carmen Ascaso
- Museo Nacional de Ciencias Naturales, CSICMadrid Spain
| | - Octavio Artieda
- Departamento Biologica Vegetal, Ecologia y ciencias de la TierraUniversidad de ExtremaduraPlasencia Spain
| | - P. R. McCullough
- Department of Physics and AstronomyThe Johns Hopkins UniversityBaltimore MD USA
| | | |
Collapse
|
11
|
Khomutovska N, Jerzak M, Kostrzewska-Szlakowska I, Kwiatowski J, Suska-Malawska M, Syczewski M, Jasser I. Life in Extreme Habitats: Diversity of Endolithic Microorganisms from Cold Desert Ecosystems of Eastern Pamir. POLISH JOURNAL OF ECOLOGY 2017. [DOI: 10.3161/15052249pje2017.65.4.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Nataliia Khomutovska
- Department of Plant Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warszawa, Poland,
| | - Maja Jerzak
- Department of Plant Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warszawa, Poland,
| | | | - Jan Kwiatowski
- Department of Molecular Phylogenetics and Evolution, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warszawa, Poland
| | - Małgorzata Suska-Malawska
- Department of Plant Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warszawa, Poland,
| | - Marcin Syczewski
- Institute of Geochemistry, Mineralogy and Petrology, Faculty of Geology, University of Warsaw, Żwirki i Wigury 93, 02-089 Warszawa, Poland
| | - Iwona Jasser
- Department of Plant Ecology and Environmental Conservation, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warszawa, Poland,
| |
Collapse
|
12
|
Lee KC, Archer SDJ, Boyle RH, Lacap-Bugler DC, Belnap J, Pointing SB. Niche Filtering of Bacteria in Soil and Rock Habitats of the Colorado Plateau Desert, Utah, USA. Front Microbiol 2016; 7:1489. [PMID: 27725810 PMCID: PMC5035745 DOI: 10.3389/fmicb.2016.01489] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Accepted: 09/07/2016] [Indexed: 11/13/2022] Open
Abstract
A common feature of microbial colonization in deserts is biological soil crusts (BSCs), and these comprise a complex community dominated by Cyanobacteria. Rock substrates, particularly sandstone, are also colonized by microbial communities. These are separated by bare sandy soil that also supports microbial colonization. Here we report a high-throughput sequencing study of BSC and cryptoendolith plus adjacent bare soil communities in the Colorado Plateau Desert, Utah, USA. Bare soils supported a community with low levels of recoverable DNA and high evenness, whilst BSC yielded relatively high recoverable DNA, and reduced evenness compared to bare soil due to specialized crust taxa. The cryptoendolithic community displayed the greatest evenness but the lowest diversity, reflecting the highly specialized nature of these communities. A strong substrate-dependent pattern of community assembly was observed, and in particular cyanobacterial taxa were distinct. Soils were virtually devoid of photoautotrophic signatures, BSC was dominated by a closely related group of Microcoleus/Phormidium taxa, whilst cryptoendolithic colonization in sandstone supported almost exclusively a single genus, Chroococcidiopsis. We interpret this as strong evidence for niche filtering of taxa in communities. Local inter-niche recruitment of photoautotrophs may therefore be limited and so communities likely depend significantly on cyanobacterial recruitment from distant sources of similar substrate. We discuss the implication of this finding in terms of conservation and management of desert microbiota.
Collapse
Affiliation(s)
- Kevin C Lee
- Institute for Applied Ecology New Zealand, School of Science, Auckland University of Technology, Auckland New Zealand
| | - Stephen D J Archer
- Institute for Applied Ecology New Zealand, School of Science, Auckland University of Technology, Auckland New Zealand
| | - Rachel H Boyle
- Institute for Applied Ecology New Zealand, School of Science, Auckland University of Technology, Auckland New Zealand
| | - Donnabella C Lacap-Bugler
- Institute for Applied Ecology New Zealand, School of Science, Auckland University of Technology, Auckland New Zealand
| | - Jayne Belnap
- U.S. Geological Survey, Southwest Biological Science Center, Moab, UT USA
| | - Stephen B Pointing
- Institute for Applied Ecology New Zealand, School of Science, Auckland University of Technology, AucklandNew Zealand; Institute of Nature and Environmental Technology, Kanazawa University, KanazawaJapan
| |
Collapse
|
13
|
Archer SDJ, de los Ríos A, Lee KC, Niederberger TS, Cary SC, Coyne KJ, Douglas S, Lacap-Bugler DC, Pointing SB. Endolithic microbial diversity in sandstone and granite from the McMurdo Dry Valleys, Antarctica. Polar Biol 2016. [DOI: 10.1007/s00300-016-2024-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
14
|
Annual development of mat-forming conjugating green algae Zygnema spp. in hydro-terrestrial habitats in the Arctic. Polar Biol 2016. [DOI: 10.1007/s00300-016-1889-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
15
|
Brandt A, Posthoff E, de Vera JP, Onofri S, Ott S. Characterisation of Growth and Ultrastructural Effects of the Xanthoria elegans Photobiont After 1.5 Years of Space Exposure on the International Space Station. ORIGINS LIFE EVOL B 2016; 46:311-21. [PMID: 26526425 DOI: 10.1007/s11084-015-9470-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 10/05/2015] [Indexed: 10/22/2022]
Abstract
The lichen Xanthoria elegans has been exposed to space and simulated Mars-analogue environment in the Lichen and Fungi Experiment (LIFE) on the EXPOSE-E facility at the International Space Station (ISS). This long-term exposure of 559 days tested the ability of various organisms to cope with either low earth orbit (LEO) or Mars-analogue conditions, such as vacuum, Mars-analogue atmosphere, rapid temperature cycling, cosmic radiation of up to 215 ± 16 mGy, and insolation of accumulated doses up to 4.87 GJm(-2), including up to 0.314 GJm(-2) of UV irradiation. In a previous study, X. elegans demonstrated considerable resistance towards these conditions by means of photosynthetic activity as well as by post-exposure metabolic activity of 50-80% in the algal and 60-90% in the fungal symbiont (Brandt et al. Int J Astrobiol 14(3):411-425, 2015). The two objectives of the present study were complementary: First, to verify the high post-exposure viability by using a qualitative cultivation assay. Second, to characterise the cellular damages by transmission electron microscopy (TEM) which were caused by the space and Mars-analogue exposure conditions of LIFE. Since the algal symbiont of lichens is considered as the more susceptible partner (de Vera and Ott 2010), the analyses focused on the photobiont. The study demonstrated growth and proliferation of the isolated photobiont after all exposure conditions of LIFE. The ultrastructural analysis of the algal cells provided an insight to cellular damages caused by long-term exposure and highlighted that desiccation-induced breakdown of cellular integrity is more pronounced under the more severe space vacuum than under Mars-analogue atmospheric conditions. In conclusion, desiccation-induced damages were identified as a major threat to the photobiont of X. elegans. Nonetheless, a fraction of the photobiont cells remained cultivable after all exposure conditions tested in LIFE.
Collapse
Affiliation(s)
- Annette Brandt
- Institute of Botany, Heinrich-Heine-University (HHU), Universitaetsstr. 1, 40225, Duesseldorf, Germany
| | - Eva Posthoff
- Institute of Botany, Heinrich-Heine-University (HHU), Universitaetsstr. 1, 40225, Duesseldorf, Germany
| | - Jean-Pierre de Vera
- Institute of Planetary Research, German Aerospace Center (DLR), Rutherfordstr. 2, 12489, Berlin, Germany
| | - Silvano Onofri
- Department of Ecological and Biological Sciences (DEB), Tuscia University, Largo dell'Università, 01100, Viterbo, Italy
| | - Sieglinde Ott
- Institute of Botany, Heinrich-Heine-University (HHU), Universitaetsstr. 1, 40225, Duesseldorf, Germany.
| |
Collapse
|
16
|
|
17
|
Purvis OW. Adaptation and interaction of saxicolous crustose lichens with metals. BOTANICAL STUDIES 2014; 55:23. [PMID: 28510922 PMCID: PMC5430356 DOI: 10.1186/1999-3110-55-23] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 12/24/2013] [Indexed: 05/02/2023]
Abstract
One of the most successful mechanisms enabling fungi to survive in extreme subaerial environments is by formation of mutualistic symbioses with algae and/or cyanobacteria as lichens. Collections, field and mineral weathering studies and developments in modern instrumental and analytical techniques have considerably advanced knowledge in understanding tolerance mechanisms to stress, environmental adaptation, species concepts and evolutionary processes in lichens colonising metalliferous habitats. This review focuses on the predominantly saxicolous, crustose, taxonomically notoriously challenging Acarospora sens. lat. Pioneering studies investigating element and substance localization in Acarospora sens. lat. in different geological terrains led to the discovery of novel fixation mechanisms, new minerals and substances associated with lichens, and new taxa and evolutionary lineages. Acarospora sens. lat. are generally under-represented in collections. Systematic sampling of Acarospora sens. lat. and other saxicolous lichens, in different mineralogical environments is now required, a priority being those occurring in extreme habitats at risk from climatic and other environmental changes. The potential for the discovery of new lichen and mineral species associated with Acarospora and other saxicolous crustose lichens, is high. These may represent special mechanisms to tolerate metal toxicity and other forms of environmental stress, including photoprotection.
Collapse
Affiliation(s)
- Ole William Purvis
- Camborne School of Mines, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Cornwall Campus, Penryn, TR10 9EZ, UK.
| |
Collapse
|
18
|
Wei STS, Fernandez-Martinez MA, Chan Y, Van Nostrand JD, de los Rios-Murillo A, Chiu JMY, Ganeshram AM, Cary SC, Zhou J, Pointing SB. Diverse metabolic and stress-tolerance pathways in chasmoendolithic and soil communities of Miers Valley, McMurdo Dry Valleys, Antarctica. Polar Biol 2014. [DOI: 10.1007/s00300-014-1598-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
19
|
de los Ríos A, Cary C, Cowan D. The spatial structures of hypolithic communities in the Dry Valleys of East Antarctica. Polar Biol 2014. [DOI: 10.1007/s00300-014-1564-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
20
|
Yung CCM, Chan Y, Lacap DC, Pérez-Ortega S, de Los Rios-Murillo A, Lee CK, Cary SC, Pointing SB. Characterization of chasmoendolithic community in Miers Valley, McMurdo Dry Valleys, Antarctica. MICROBIAL ECOLOGY 2014; 68:351-359. [PMID: 24671755 DOI: 10.1007/s00248-014-0412-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 03/11/2014] [Indexed: 05/28/2023]
Abstract
The Antarctic Dry Valleys are unable to support higher plant and animal life and so microbial communities dominate biotic ecosystem processes. Soil communities are well characterized, but rocky surfaces have also emerged as a significant microbial habitat. Here, we identify extensive colonization of weathered granite on a landscape scale by chasmoendolithic microbial communities. A transect across north-facing and south-facing slopes plus valley floor moraines revealed 30-100 % of available substrate was colonized up to an altitude of 800 m. Communities were assessed at a multidomain level and were clearly distinct from those in surrounding soils and other rock-inhabiting cryptoendolithic and hypolithic communities. All colonized rocks were dominated by the cyanobacterial genus Leptolyngbya (Oscillatoriales), with heterotrophic bacteria, archaea, algae, and fungi also identified. Striking patterns in community distribution were evident with regard to microclimate as determined by aspect. Notably, a shift in cyanobacterial assemblages from Chroococcidiopsis-like phylotypes (Pleurocapsales) on colder-drier slopes, to Synechococcus-like phylotypes (Chroococcales) on warmer-wetter slopes. Greater relative abundance of known desiccation-tolerant bacterial taxa occurred on colder-drier slopes. Archaeal phylotypes indicated halotolerant taxa and also taxa possibly derived from nearby volcanic sources. Among the eukaryotes, the lichen photobiont Trebouxia (Chlorophyta) was ubiquitous, but known lichen-forming fungi were not recovered. Instead, fungal assemblages were dominated by ascomycetous yeasts. We conclude that chasmoendoliths likely constitute a significant geobiological phenomenon at lower elevations in granite-dominated Antarctic Dry Valley systems.
Collapse
Affiliation(s)
- Charmaine C M Yung
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
| | | | | | | | | | | | | | | |
Collapse
|
21
|
De Maayer P, Anderson D, Cary C, Cowan DA. Some like it cold: understanding the survival strategies of psychrophiles. EMBO Rep 2014; 15:508-17. [PMID: 24671034 DOI: 10.1002/embr.201338170] [Citation(s) in RCA: 301] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Much of the Earth's surface, both marine and terrestrial, is either periodically or permanently cold. Although habitats that are largely or continuously frozen are generally considered to be inhospitable to life, psychrophilic organisms have managed to survive in these environments. This is attributed to their innate adaptive capacity to cope with cold and its associated stresses. Here, we review the various environmental, physiological and molecular adaptations that psychrophilic microorganisms use to thrive under adverse conditions. We also discuss the impact of modern "omic" technologies in developing an improved understanding of these adaptations, highlighting recent work in this growing field.
Collapse
Affiliation(s)
- Pieter De Maayer
- Centre for Microbial Ecology and Genomics (CMEG), Department of Genetics, University of Pretoria, Pretoria, South Africa
| | | | | | | |
Collapse
|
22
|
Fluorescent fingerprints of endolithic phototrophic cyanobacteria living within halite rocks in the Atacama Desert. Appl Environ Microbiol 2014; 80:2998-3006. [PMID: 24610843 DOI: 10.1128/aem.03428-13] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Halite deposits from the hyperarid zone of the Atacama Desert reveal the presence of endolithic microbial colonization dominated by cyanobacteria associated with heterotrophic bacteria and archaea. Using the λ-scan confocal laser scanning microscopy (CLSM) option, this study examines the autofluorescence emission spectra produced by single cyanobacterial cells found inside halite rocks and by their photosynthetic pigments. Photosynthetic pigments could be identified according to the shapes of the emission spectra and wavelengths of fluorescence peaks. According to their fluorescence fingerprints, three groups of cyanobacterial cells were identified within this natural extreme microhabitat: (i) cells producing a single fluorescence peak corresponding to the emission range of phycobiliproteins and chlorophyll a, (ii) cells producing two fluorescence peaks within the red and green signal ranges, and (iii) cells emitting only low-intensity fluorescence within the nonspecific green fluorescence signal range. Photosynthetic pigment fingerprints emerged as indicators of the preservation state or viability of the cells. These observations were supported by a cell plasma membrane integrity test based on Sytox Green DNA staining and by transmission electron microscopy ultrastructural observations of cyanobacterial cells.
Collapse
|
23
|
Pichrtová M, Hájek T, Elster J. Osmotic stress and recovery in field populations of Zygnema sp. (Zygnematophyceae, Streptophyta) on Svalbard (High Arctic) subjected to natural desiccation. FEMS Microbiol Ecol 2014; 89:270-80. [PMID: 24476153 DOI: 10.1111/1574-6941.12288] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 01/06/2014] [Accepted: 01/16/2014] [Indexed: 12/01/2022] Open
Abstract
Zygnema is a genus of filamentous green algae belonging to the class of Zygnematophyceae (Streptophyta). In the Arctic, it typically forms extensive mats in habitats that regularly dry out during summer, and therefore, mechanisms of stress resistance are expected. We investigated its natural populations with respect to production of specialized desiccation-resistant cells and osmotic acclimation. Six populations in various stages of natural desiccation were selected, from wet biomass floating in water to dried paper-like crusts. After rewetting, plasmolysis and osmotic stress effects were studied using hypertonic sorbitol solutions, and the physiological state was estimated using chlorophyll a fluorescence parameters. All populations of Zygnema sp. formed stationary-phase cells filled with storage products. In green algal research, such cells are traditionally called akinetes. However, the populations differed in their reaction to osmotic stress. Whereas the wet-collected samples were strongly impaired, the osmotic stress resistance of the naturally dried samples was comparable to that of true aeroterrestrial algae. We showed that arctic populations of Zygnema acclimate well to natural desiccation via hardening that is mediated by slow desiccation. As no other types of specialized cells were observed, we assume that the naturally hardened akinetes also play a key role in winter survival.
Collapse
Affiliation(s)
- Martina Pichrtová
- Institute of Botany, Academy of Sciences of the Czech Republic, Třeboň, Czech Republic; Department of Botany, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | | | | |
Collapse
|
24
|
Barnett MJ, Pearce DA, Cullen DC. Advances in the in-field detection of microorganisms in ice. ADVANCES IN APPLIED MICROBIOLOGY 2012; 81:133-67. [PMID: 22958529 DOI: 10.1016/b978-0-12-394382-8.00004-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The historic view of ice-bound ecosystems has been one of a predominantly lifeless environment, where microorganisms certainly exist but are assumed to be either completely inactive or in a state of long-term dormancy. However, this standpoint has been progressively overturned in the past 20years as studies have started to reveal the importance of microbial life in the functioning of these environments. Our present knowledge of the distribution, taxonomy, and metabolic activity of such microbial life has been derived primarily from laboratory-based analyses of collected field samples. To date, only a restricted range of life detection and characterization techniques have been applied in the field. Specific examples include direct observation and DNA-based techniques (microscopy, specific stains, and community profiling based on PCR amplification), the detection of biomarkers (such as adenosine triphosphate), and measurements of metabolism [through the uptake and incorporation of radiolabeled isotopes or chemical alteration of fluorescent substrates (umbelliferones are also useful here)]. On-going improvements in technology mean that smaller and more robust life detection and characterization systems are continually being designed, manufactured, and adapted for in-field use. Adapting technology designed for other applications is the main source of new methodology, and the range of techniques is currently increasing rapidly. Here we review the current use of technology and techniques to detect and characterize microbial life within icy environments and specifically its deployment to in-field situations. We discuss the necessary considerations, limitations, and adaptations, review emerging technologies, and highlight the future potential. Successful application of these new techniques to in-field studies will certainly generate new insights into the way ice bound ecosystems function.
Collapse
Affiliation(s)
- Megan J Barnett
- Cranfield Health, Vincent Building, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
| | | | | |
Collapse
|
25
|
Miller AZ, Sanmartín P, Pereira-Pardo L, Dionísio A, Saiz-Jimenez C, Macedo MF, Prieto B. Bioreceptivity of building stones: a review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2012; 426:1-12. [PMID: 22534363 DOI: 10.1016/j.scitotenv.2012.03.026] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 03/09/2012] [Accepted: 03/10/2012] [Indexed: 05/31/2023]
Abstract
In 1995, Guillitte defined bioreceptivity, a new term in ecology, as the ability of a material to be colonized by living organisms. Information about the bioreceptivity of stone is of great importance since it will help us to understand the material properties which influence the development of biological colonization in the built environment, and will also provide useful information as regards selecting stones for the conservation of heritage monuments and construction of new buildings. Studies of the bioreceptivity of stone materials are reviewed here with the aim of providing a clear set of conclusions on the topic. Definitions of bioreceptivity are given, stone bioreceptivity experiments are described, and finally the stone properties related to bioreceptivity are discussed. We suggest that a standardized laboratory protocol for evaluating stone bioreceptivity and definition of a stone bioreceptivity index are required to enable creation of a database on the primary bioreceptivity of stone materials.
Collapse
Affiliation(s)
- A Z Miller
- Centro de Petrologia e Geoquímica, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001, Lisboa, Portugal.
| | | | | | | | | | | | | |
Collapse
|
26
|
Scalzi G, Selbmann L, Zucconi L, Rabbow E, Horneck G, Albertano P, Onofri S. LIFE experiment: isolation of cryptoendolithic organisms from Antarctic colonized sandstone exposed to space and simulated Mars conditions on the international space station. ORIGINS LIFE EVOL B 2012; 42:253-62. [PMID: 22688852 DOI: 10.1007/s11084-012-9282-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 04/05/2012] [Indexed: 10/27/2022]
Abstract
Desiccated Antarctic rocks colonized by cryptoendolithic communities were exposed on the International Space Station (ISS) to space and simulated Mars conditions (LiFE-Lichens and Fungi Experiment). After 1.5 years in space samples were retrieved, rehydrated and spread on different culture media. Colonies of a green alga and a pink-coloured fungus developed on Malt-Agar medium; they were isolated from a sample exposed to simulated Mars conditions beneath a 0.1 % T Suprasil neutral density filter and from a sample exposed to space vacuum without solar radiation exposure, respectively. None of the other flight samples showed any growth after incubation. The two organisms able to grow were identified at genus level by Small SubUnit (SSU) and Internal Transcribed Spacer (ITS) rDNA sequencing as Stichococcus sp. (green alga) and Acarospora sp. (lichenized fungal genus) respectively. The data in the present study provide experimental information on the possibility of eukaryotic life transfer from one planet to another by means of rocks and of survival in Mars environment.
Collapse
Affiliation(s)
- Giuliano Scalzi
- Department of Ecological and Biological Sciences, University of Tuscia, Largo dell'Università snc, 01100, Viterbo, Italy.
| | | | | | | | | | | | | |
Collapse
|
27
|
Onofri S, Barreca D, Selbmann L, Isola D, Rabbow E, Horneck G, de Vera JPP, Hatton J, Zucconi L. Resistance of Antarctic black fungi and cryptoendolithic communities to simulated space and Martian conditions. Stud Mycol 2011; 61:99-109. [PMID: 19287532 PMCID: PMC2610303 DOI: 10.3114/sim.2008.61.10] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Dried colonies of the Antarctic rock-inhabiting meristematic fungi
Cryomyces antarcticus CCFEE 515, CCFEE 534 and C. minteri
CCFEE 5187, as well as fragments of rocks colonized by the Antarctic
cryptoendolithic community, were exposed to a set of ground-based experiment
verification tests (EVTs) at the German Aerospace Center (DLR, Köln,
Germany). These were carried out to test the tolerance of these organisms in
view of their possible exposure to space conditions outside of the
International Space Station (ISS). Tests included single or combined simulated
space and Martian conditions. Responses were analysed both by cultural and
microscopic methods. Thereby, colony formation capacities were measured and
the cellular viability was assessed using live/dead dyes FUN 1 and SYTOX
Green. The results clearly suggest a general good resistance of all the
samples investigated. C. minteri CCFEE 5187, C. antarcticus
CCFEE 515 and colonized rocks were selected as suitable candidates to
withstand space flight and long-term permanence in space on the ISS in the
framework of the LIchens and Fungi Experiments (LIFE programme, European Space
Agency).
Collapse
Affiliation(s)
- S Onofri
- DECOS, Università degli Studi della Tuscia, Largo dell'Università, Viterbo, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Hart KM, Szpak MT, Mahaney WC, Dohm JM, Jordan SF, Frazer AR, Allen CCR, Kelleher BP. A bacterial enrichment study and overview of the extractable lipids from paleosols in the Dry Valleys, Antarctica: implications for future Mars reconnaissance. ASTROBIOLOGY 2011; 11:303-321. [PMID: 21545270 DOI: 10.1089/ast.2010.0583] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The Dry Valleys of Antarctica are one of the coldest and driest environments on Earth with paleosols in selected areas that date to the emplacement of tills by warm-based ice during the Early Miocene. Cited as an analogue to the martian surface, the ability of the Antarctic environment to support microbial life-forms is a matter of special interest, particularly with the upcoming NASA/ESA 2018 ExoMars mission. Lipid biomarkers were extracted and analyzed by gas chromatography--mass spectrometry to assess sources of organic carbon and evaluate the contribution of microbial species to the organic matter of the paleosols. Paleosol samples from the ice-free Dry Valleys were also subsampled and cultivated in a growth medium from which DNA was extracted with the explicit purpose of the positive identification of bacteria. Several species of bacteria were grown in solution and the genus identified. A similar match of the data to sequenced DNA showed that Alphaproteobacteria, Gammaproteobacteria, Bacteriodetes, and Actinobacteridae species were cultivated. The results confirm the presence of bacteria within some paleosols, but no assumptions have been made with regard to in situ activity at present. These results underscore the need not only to further investigate Dry Valley cryosols but also to develop reconnaissance strategies to determine whether such likely Earth-like environments on the Red Planet also contain life.
Collapse
Affiliation(s)
- Kris M Hart
- School of Chemical Sciences, Dublin City University, Dublin, Ireland.
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Space Flight Effects on Lichen Ultrastructure and Physiology. CELLULAR ORIGIN, LIFE IN EXTREME HABITATS AND ASTROBIOLOGY 2010. [DOI: 10.1007/978-90-481-9449-0_30] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
30
|
Pointing SB, Chan Y, Lacap DC, Lau MCY, Jurgens JA, Farrell RL. Highly specialized microbial diversity in hyper-arid polar desert. Proc Natl Acad Sci U S A 2009; 106:19964-9. [PMID: 19850879 PMCID: PMC2765924 DOI: 10.1073/pnas.0908274106] [Citation(s) in RCA: 241] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2009] [Indexed: 11/18/2022] Open
Abstract
The McMurdo Dry Valleys in Antarctica are a cold hyperarid polar desert that present extreme challenges to life. Here, we report a culture-independent survey of multidomain microbial biodiversity in McKelvey Valley, a pristine example of the coldest desert on Earth. We demonstrate that life has adapted to form highly-specialized communities in distinct lithic niches occurring concomitantly within this terrain. Endoliths and chasmoliths in sandstone displayed greatest diversity, whereas soil was relatively depauperate and lacked a significant photoautotrophic component, apart from isolated islands of hypolithic cyanobacterial colonization on quartz rocks in soil contact. Communities supported previously unreported polar bacteria and fungi, but archaea were absent from all niches. Lithic community structure did not vary significantly on a landscape scale and stochastic moisture input due to snowmelt resulted in increases in colonization frequency without significantly affecting diversity. The findings show that biodiversity near the cold-arid limit for life is more complex than previously appreciated, but communities lack variability probably due to the high selective pressures of this extreme environment.
Collapse
Affiliation(s)
- Stephen B. Pointing
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Yuki Chan
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Donnabella C. Lacap
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Maggie C. Y. Lau
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Joel A. Jurgens
- Department of Plant Pathology, University of Minnesota, St Paul, MN 55108-6030; and
- Department of Biological Sciences, The University of Waikato, Hamilton, New Zealand
| | - Roberta L. Farrell
- Department of Biological Sciences, The University of Waikato, Hamilton, New Zealand
| |
Collapse
|
31
|
Gorbushina AA, Broughton WJ. Microbiology of the atmosphere-rock interface: how biological interactions and physical stresses modulate a sophisticated microbial ecosystem. Annu Rev Microbiol 2009; 63:431-50. [PMID: 19575564 DOI: 10.1146/annurev.micro.091208.073349] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Life at the atmosphere-lithosphere boundary is an ancient terrestrial niche that is sparsely covered by thin subaerial biofilms. The microbial inhabitants of these biofilms (a) have adapted to all types of terrestrial/subaerial stresses (e.g., desiccation, extreme temperatures, low nutrient availability, intense solar radiation), (b) interact with minerals that serve as both a dwelling and a source of mineral nutrients, and (c) provoke weathering of rocks and soil formation. Subaerial communities comprise heterotrophic and phototrophic microorganisms that support each other's lifestyle. Major lineages of eubacteria associated with the early colonization of land (e.g., Actinobacteria, Cyanobacteria) are present in these habitats along with eukaryotes such as microscopic green algae and ascomycetous fungi. The subaerial biofilm inhabitants have adapted to desiccation, solar radiation, and other environmental challenges by developing protective, melanized cell walls, assuming microcolonial architectures and symbiotic lifestyles. How these changes occurred, their significance in soil formation, and their potential as markers of climate change are discussed below.
Collapse
Affiliation(s)
- Anna A Gorbushina
- Department IV-Materials and Environment, BAM (Federal Institute for Material Research & Testing), D-Berlin 12205 , Germany.
| | | |
Collapse
|
32
|
Stivaletta N, Barbieri R. Endoliths in Terrestrial Arid Environments: Implications for Astrobiology. CELLULAR ORIGIN, LIFE IN EXTREME HABITATS AND ASTROBIOLOGY 2008. [DOI: 10.1007/978-1-4020-8837-7_15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|
33
|
Knowles EJ, Castenholz RW. Effect of exogenous extracellular polysaccharides on the desiccation and freezing tolerance of rock-inhabiting phototrophic microorganisms. FEMS Microbiol Ecol 2008; 66:261-70. [DOI: 10.1111/j.1574-6941.2008.00568.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
34
|
Omelon CR, Pollard WH, Ferris FG. Inorganic species distribution and microbial diversity within high Arctic cryptoendolithic habitats. MICROBIAL ECOLOGY 2007; 54:740-52. [PMID: 17457639 DOI: 10.1007/s00248-007-9235-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Revised: 01/04/2007] [Accepted: 01/05/2007] [Indexed: 05/15/2023]
Abstract
Cryptoendolithic habitats in the Canadian high Arctic are associated with a variety of microbial community assemblages, including cyanobacteria, algae, and fungi. These habitats were analyzed for the presence of metal ions by sequential extraction and evaluated for relationships between these and the various microorganisms found at each site using multivariate statistical methods. Cyanobacteria-dominated communities exist under higher pH conditions with elevated concentrations of calcium and magnesium, whereas communities dominated by fungi and algae are characterized by lower pH conditions and higher concentrations of iron, aluminum, and silicon in the overlying surfaces. These results suggest that the activity of the dominant microorganisms controls the pH of the surrounding environment, which in turn dictates rates of weathering or the possibility for surface crust formation, both ultimately deciding the structure of microbial diversity for each cryptoendolithic habitat.
Collapse
Affiliation(s)
- Christopher R Omelon
- Department of Geology, University of Toronto, 22 Russell Street, Toronto, Ontario, M5S-3B1, Canada.
| | | | | |
Collapse
|
35
|
Abstract
The endolithic environment, the pore space in rocks, is a ubiquitous microbial habitat and an interface between biology and geology. Photosynthesis-based endolithic communities inhabit the outer centimeters of rocks exposed to the surface, and offer model systems for microbial ecology, geobiology, and astrobiology. Endolithic ecosystems are among the simplest microbial ecosystems known and as such provide tractable models for testing ecological hypotheses. Such hypotheses have been difficult to test because microbial ecosystems are extraordinarily diverse. We review here recent culture-independent, ribosomal RNA-based studies that evaluate hypotheses about endolithic ecosystems, and provide insight for understanding general principles in microbial ecology. Comparison of endolithic communities supports the principle that patterns of microbial diversity are governed by similar principles observed in macroecological systems. Recent results also explore geobiological processes that shape the current biosphere and potentially provide clues to life's history on Earth and where to seek life elsewhere in the Solar System.
Collapse
Affiliation(s)
- Jeffrey J Walker
- University of Colorado at Boulder, Department of Molecular, Cellular and Developmental Biology, Boulder, Colorado 80309-0347, USA.
| | | |
Collapse
|
36
|
Warren-Rhodes KA, Rhodes KL, Boyle LN, Pointing SB, Chen Y, Liu S, Zhuo P, McKay CP. Cyanobacterial ecology across environmental gradients and spatial scales in China's hot and cold deserts. FEMS Microbiol Ecol 2007; 61:470-82. [PMID: 17672851 DOI: 10.1111/j.1574-6941.2007.00351.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Lithic photoautotrophic communities function as principal primary producers in the world's driest deserts, yet many aspects of their ecology remain unknown. This is particularly true for Asia, where some of the Earth's oldest and driest deserts occur. Using methods derived from plant landscape ecology, we measured the abundance and spatial distribution of cyanobacterial colonization on quartz stony pavement across environmental gradients of rainfall and temperature in the isolated Taklimakan and Qaidam Basin deserts of western China. Colonization within available habitat ranged from 0.37+/-0.16% to 12.6+/-1.8%, with cold dry desert sites exhibiting the lowest abundance. Variation between sites was most strongly correlated with moisture-related variables and was independent of substrate availability. Cyanobacterial communities were spatially aggregated at multiple scales in patterns distinct from the underlying rock pattern. Site-level differences in cyanobacterial spatial pattern (e.g. mean inter-patch distance) were linked with rainfall, whereas patchiness within sites was correlated with local geology (greater colonization frequency of large rocks) and biology (dispersal during rainfall). We suggest that cyanobacterial patchiness may also in part be self-organized - that is, an outcome of soil water-biological feedbacks. We propose that landscape ecology concepts and models linking desert vegetation, biological feedbacks and ecohydrological processes are applicable to microbial communities.
Collapse
|
37
|
Dong H, Rech JA, Jiang H, Sun H, Buck BJ. Endolithic cyanobacteria in soil gypsum: Occurrences in Atacama (Chile), Mojave (United States), and Al-Jafr Basin (Jordan) Deserts. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jg000385] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
38
|
Sancho LG, de la Torre R, Horneck G, Ascaso C, de Los Rios A, Pintado A, Wierzchos J, Schuster M. Lichens survive in space: results from the 2005 LICHENS experiment. ASTROBIOLOGY 2007; 7:443-54. [PMID: 17630840 DOI: 10.1089/ast.2006.0046] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
This experiment was aimed at establishing, for the first time, the survival capability of lichens exposed to space conditions. In particular, the damaging effect of various wavelengths of extraterrestrial solar UV radiation was studied. The lichens used were the bipolar species Rhizocarpon geographicum and Xanthoria elegans, which were collected above 2000 m in the mountains of central Spain and as endolithic communities inhabiting granites in the Antarctic Dry Valleys. Lichens were exposed to space in the BIOPAN-5 facility of the European Space Agency; BIOPAN-5 is located on the outer shell of the Earth-orbiting FOTON-M2 Russian satellite. The lichen samples were launched from Baikonur by a Soyuz rocket on May 31, 2005, and were returned to Earth after 16 days in space, at which time they were tested for survival. Chlorophyll fluorescence was used for the measurement of photosynthetic parameters. Scanning electron microscopy in back-scattered mode, low temperature scanning electron microscopy, and transmission electron microscopy were used to study the organization and composition of both symbionts. Confocal laser scanning microscopy, in combination with the use of specific fluorescent probes, allowed for the assessment of the physiological state of the cells. All exposed lichens, regardless of the optical filters used, showed nearly the same photosynthetic activity after the flight as measured before the flight. Likewise, the multimicroscopy approach revealed no detectable ultrastructural changes in most of the algal and fungal cells of the lichen thalli, though a greater proportion of cells in the flight samples had compromised membranes, as revealed by the LIVE/DEAD BacLight Bacterial Viability Kit. These findings indicate that most lichenized fungal and algal cells can survive in space after full exposure to massive UV and cosmic radiation, conditions proven to be lethal to bacteria and other microorganisms. The lichen upper cortex seems to provide adequate protection against solar radiation. Moreover, after extreme dehydration induced by high vacuum, the lichens proved to be able to recover, in full, their metabolic activity within 24 hours.
Collapse
Affiliation(s)
- Leopoldo G Sancho
- Departamento de Biología Vegetal II, Universidad Complutense, Madrid, Spain.
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Gadd GM. Geomycology: biogeochemical transformations of rocks, minerals, metals and radionuclides by fungi, bioweathering and bioremediation. ACTA ACUST UNITED AC 2007; 111:3-49. [PMID: 17307120 DOI: 10.1016/j.mycres.2006.12.001] [Citation(s) in RCA: 456] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Revised: 11/26/2006] [Accepted: 12/12/2006] [Indexed: 11/25/2022]
Abstract
The study of the role that fungi have played and are playing in fundamental geological processes can be termed 'geomycology' and this article seeks to emphasize the fundamental importance of fungi in several key areas. These include organic and inorganic transformations and element cycling, rock and mineral transformations, bioweathering, mycogenic mineral formation, fungal-clay interactions, metal-fungal interactions, and the significance of such processes in the environment and their relevance to areas of environmental biotechnology such as bioremediation. Fungi are intimately involved in biogeochemical transformations at local and global scales, and although such transformations occur in both aquatic and terrestrial habitats, it is the latter environment where fungi probably have the greatest influence. Within terrestrial aerobic ecosystems, fungi may exert an especially profound influence on biogeochemical processes, particularly when considering soil, rock and mineral surfaces, and the plant root-soil interface. The geochemical transformations that take place can influence plant productivity and the mobility of toxic elements and substances, and are therefore of considerable socio-economic relevance, including human health. Of special significance are the mutualistic symbioses, lichens and mycorrhizas. Some of the fungal transformations discussed have beneficial applications in environmental biotechnology, e.g. in metal leaching, recovery and detoxification, and xenobiotic and organic pollutant degradation. They may also result in adverse effects when these processes are associated with the degradation of foodstuffs, natural products, and building materials, including wood, stone and concrete. It is clear that a multidisciplinary approach is essential to understand fully all the phenomena encompassed within geomycology, and it is hoped that this review will serve to catalyse further research, as well as stimulate interest in an area of mycology of global significance.
Collapse
Affiliation(s)
- Geoffrey M Gadd
- Division of Environmental and Applied Biology, College of Life Sciences, University of Dundee, Dundee DD1 4HN, UK.
| |
Collapse
|
40
|
de los Ríos A, Grube M, Sancho LG, Ascaso C. Ultrastructural and genetic characteristics of endolithic cyanobacterial biofilms colonizing Antarctic granite rocks. FEMS Microbiol Ecol 2007; 59:386-95. [PMID: 17328119 DOI: 10.1111/j.1574-6941.2006.00256.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The precise identification of the cyanobacteria that comprise an endolithic biofilm is hindered by difficulties in culturing the organisms found in these biofilms and a lack of previous molecular and ultrastructural data. This study characterizes, both at the ultrastructural and molecular level, two different cyanobacterial biofilms found in fissures of granite from continental Antarctica. Electron microscopy revealed structural differences between the two biofilms. One was only loosely adhered to the substrate, while the other biofilm showed a closer association between cells and rock minerals and was tightly attached to the substrate. Cells from both biofilms where ultrastructurally distinct, displaying, for instance, clear differences in their sheaths. The amounts of EPS and their organization associated with the cyanobacteria may determine the differences in adhesion and effects on the lithic substrate observed in the biofilms. By sequencing part of the 16S rRNA gene, the two cyanobacteria were also genetically characterized. The gene sequence of the cells comprising the biofilm that was tightly attached to the lithic substrate showed most homology with that of an endolithic cyanobacterium from Switzerland (AY153458), and the cyanobacterial type loosely adhered to the rock, clustered with Acaryochloris marina, the only organism unequivocally known to contain chlorophyll d. This study reveals the presence of at least two different types of endolithic biofilm, dominated each by a single type of cyanobacterium, able to withstand the harsh conditions of the Antarctic climate.
Collapse
|
41
|
Fungal Associations at the Cold Edge of Life. CELLULAR ORIGIN, LIFE IN EXTREME HABITATS AND ASTROBIOLOGY 2007. [DOI: 10.1007/978-1-4020-6112-7_40] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
42
|
Gonçalves AB, Santos IM, Paterson RRM, Lima N. FISH and Calcofluor staining techniques to detect in situ filamentous fungal biofilms in water. Rev Iberoam Micol 2006; 23:194-8. [PMID: 17196030 DOI: 10.1016/s1130-1406(06)70044-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Filamentous fungi are a ubiquitous and diverse group of eukaryotic organisms and may contribute, along with bacteria, yeasts, protozoa and viruses, to the formation of biofilms in water distribution systems. However, fungal involvement in biofilms has not been demonstrated unambiguously. Furthermore, these fungi may be responsible for the production of tastes, odours and mycotoxins in drinking water making their early detection important. The detection of fme these problems a combination of two fluorescent techniques for direct detection was tested: (a) Fluorescence In Situ Hybridization (FISH) employing the universal rRNA probe EUK516, labelled with the red Cy3, followed by (b) staining with Calcofluor White MR2 fluorescent dye which stains fungal cell walls blue. Pure cultures of Penicillium brevicompactum were used to establish the methods followed by separate experiments with real water biofilm samples in PVC-C and cast iron coupons. FISH demonstrated eukaryotic microrganisms after approximately 5 h while the calcofluor method revealed chitinous filamentous structures in less than one hour. When the two methods were combined, additional resolution was obtained from the images of filamentous walls (blue) with intact protoplasm (red). In conclusion, FISH and Calcofluor staining provide rapid, direct and unambiguous information on the involvement of ff in biofilms which form in water.
Collapse
Affiliation(s)
- Ana B Gonçalves
- Centro de Engenharia Biológica, and Micoteca da Universidade do Minho, Universidade do Minho, Braga, Portugal
| | | | | | | |
Collapse
|
43
|
Moscoso M, García E, López R. Biofilm formation by Streptococcus pneumoniae: role of choline, extracellular DNA, and capsular polysaccharide in microbial accretion. J Bacteriol 2006; 188:7785-95. [PMID: 16936041 PMCID: PMC1636320 DOI: 10.1128/jb.00673-06] [Citation(s) in RCA: 253] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae colonizes the human upper respiratory tract, and this asymptomatic colonization is known to precede pneumococcal disease. In this report, chemically defined and semisynthetic media were used to identify the initial steps of biofilm formation by pneumococcus during growth on abiotic surfaces such as polystyrene or glass. Unencapsulated pneumococci adhered to abiotic surfaces and formed a three-dimensional structure about 25 microm deep, as observed by confocal laser scanning microscopy and low-temperature scanning electron microscopy. Choline residues of cell wall teichoic acids were found to play a fundamental role in pneumococcal biofilm development. The role in biofilm formation of choline-binding proteins, which anchor to the teichoic acids of the cell envelope, was determined using unambiguously characterized mutants. The results showed that LytA amidase, LytC lysozyme, LytB glucosaminidase, CbpA adhesin, PcpA putative adhesin, and PspA (pneumococcal surface protein A) mutants had a decreased capacity to form biofilms, whereas no such reduction was observed in Pce phosphocholinesterase or CbpD putative amidase mutants. Moreover, encapsulated, clinical pneumococcal isolates were impaired in their capacity to form biofilms. In addition, a role for extracellular DNA and proteins in the establishment of S. pneumoniae biofilms was demonstrated. Taken together, these observations provide information on conditions that favor the sessile mode of growth by S. pneumoniae. The experimental approach described here should facilitate the study of bacterial genes that are required for biofilm formation. Those results, in turn, may provide insight into strategies to prevent pneumococcal colonization of its human host.
Collapse
Affiliation(s)
- Miriam Moscoso
- Departamento de Microbiología Molecular, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | | | | |
Collapse
|