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See detailANNUAL SCIENTIFIC REPORT - Climate change and Antarctic microbial biodiversity (CCAMBIO)
Tytgat, Bjorn; Willems, Anne; Sweetlove, Maxime et al

Report (2015)

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See detailDynamic responses of cyanobacterial communities following glacier retreat in the High Arctic (Svalbard)
Stelmach Pessi, Igor ULg; Pushkareva, Ekaterina; Elster, Josef et al

Scientific conference (2015, December)

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See detailA plea for the creation for inviolate areas to protect reference areas for future microbiology research in Antarctica
Wilmotte, Annick ULg; Willems, Anne; Verleyen, Elie et al

Poster (2015, September 08)

Antarctica is essentially a microbial continent. A surprisingly large biodiversity of adapted microorganisms lives permanently in various biotopes of the ice-free areas (about 44,000 km2). Based on ... [more ▼]

Antarctica is essentially a microbial continent. A surprisingly large biodiversity of adapted microorganisms lives permanently in various biotopes of the ice-free areas (about 44,000 km2). Based on molecular methods and microscopic observations, important findings like the presence of potentially endemic taxa, their survival in glacial refugia since the continent moved away from Australia and South America, and the determination of biogeographic patterns have been inferred. Moreover, Antarctic microorganisms may contain novel molecules with potentially pharmaceutical or biotechnological interest. However, microbial habitats are under pressure as a result of nthropogenic introductions. Indeed, as a consequence of human presence, non-indigenous microorganisms are released from bodies, clothing, cargo and food into the environment (Cowan et al. 2011). The increase of tourism and its diversification from coastal cruises to adventurous expeditions into the continent, as well as the increase of research stations and associated impacts, constantly create new ‘entry points‘ for microbial contamination (Chown et al. 2012). The impacts of such introductions are still unknown, and might lead to a loss of the native microbial biodiversity, or its modification by lateral gene transfer. The technical progresses in molecular methodologies, like we currently see with Next Generation Sequencing (NGS), mean that very sensitive high-throughput analyses will become increasingly accessible. They have the potential to describe the microbial communities with unprecedented details without preconceived expectations. However, by that time, we might have lost the pristine Antarctic areas that would enable the scientists to study the native microbial flora, its functioning and properties. The Protocol on Environmental Protection of the Antarctic Treaty foresees the designation of Antarctic Specially Protected Areas (ASPA) to protect “outstanding environmental, scientific, historic, aesthetic, or wilderness values, any combination of those values, or on- going or planned scientific research” (http://www.ats.aq/e/ep_protected.htm). However, the designation of ASPAs has not followed a systematic planning, and often focused on the conservation of large animals or higher plant communities. Microorganisms have the handicap of generally being invisible without a microscope and relevant expertise, and needing molecular methods to determine their identity. Terrestrial habitats are protected in 55 out of the 72 existing ASPAs (in total less than 700 km2), mostly based on the need to protect vascular plants and bryophyte communities (Shaw et al. 2014). In 28 ASPAs, the protection targets the lichens, whereas microalgae are protected in 16 ASPAs, cyanobacteria in 7 and snow microalgae in 3. Only 8 ASPAs mention ‘Microbial habitats’, ‘microbial communities’ or ‘soil and lake microflora’. One tool of the Protocol that could be specifically used to protect microbial habitats is the creation of inviolate areas where no visitation is permitted (inside ASPAs, for example). These zones could be set aside for future research (Hughes et al. 2013) and become extremely valuable. After a few decades, they would be unique examples of truly pristine habitats, representative of the native microbial diversity and processes. Such an option would necessitate discussions and consensus with scientists of other disciplines to select these regions, and careful management protocols of the sites and their vicinity (Hughes et al. 2015). In addition, gaps in knowledge should be addressed, like the extent of transportation of microorganisms by natural means (winds, birds...) (e.g. Pearce et al. 2009), and the probability of subsequent colonization of new areas by microorganisms coming from other Antarctic regions or from outside Antarctica. Let’s hope that the dialogue between scientists and policy makers will enable to improve the conservation of Antarctic microbial diversity and safeguard the possibility to study these unique communities in the future with the most advanced techniques of the time. The outcome of these discussions might also be of interest for Arctic and alpine regions. [less ▲]

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See detailCHARACTERIZATION OF TEN STRAINS OF FILAMENTOUS CYANOBACTERIA FROM THE SOUTH SHETLAND ISLANDS, MARITIME ANTARCTICA
Kovacik, Lubomir; Pereira, Antonio; Dusinsky, Roman et al

Poster (2015, September 07)

The evolutionary relationships of ten Antarctic cyanobacterial strains of the order Oscillatoriales isolated from King George Island and Deception Island, South Shetland Islands were studied by a ... [more ▼]

The evolutionary relationships of ten Antarctic cyanobacterial strains of the order Oscillatoriales isolated from King George Island and Deception Island, South Shetland Islands were studied by a polyphasic approach. Phenotypic observations of the morphological features and genotypic analyses (16S rRNA and ITS sequences) were performed. Based on major phenotypic features, the strains were divided into four distinct morphotypes: Leptolyngbya borchgrevinkii (A), Leptolyngbya frigida (B), Phormidium autumnale (C) and Wilmottia murrayi (D). This morphological identification was in global agreement with the evolutionary relationships. According to the phylogenetic analysis, the ten strains were divided into two major clades, containing related strain sequences with Leptolyngbya morphotypes in one clade and with morphotypes corresponding to Phormidium, Wilmottia and Microcoleus spp. in the other clade. Each major clade was divided into two sub-clades. For the first time, the 16S rRNA gene sequence of a strain corresponding to the Leptolyngbya borchgrevinkii morphotype (A) was determined, on the basis of strain KOVACIK-ANT 1990/4. The closest sequence to our morphotype A is the clone Fr252 isolated from microbial mat of Antarctic Lake Fryxell. Morphotype B is closest to sequences assigned to Leptolyngbya frigida isolated from microbial mats of lakes in continental East Antarctica. Morphotype C belongs to a cluster including strains with morphotypes corresponding to Phormidium autumnale from Antarctica, but also from Europe. Morphotype D is grouped with sequences of the morphotype assigned to Wilmottia murrayi isolated from Antarctica. [less ▲]

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See detailBEDROCK AND BIOTIC INFLUENCE ON COMMUNITY COMPOSITION IN SOILS FROM THE SØR RONDANE MOUNTAINS, EAST ANTARCTICA
Tytgat, Bjorn; Verleyen, Elie; D'hondt, Sofie et al

Poster (2015, September 07)

Antarctica is a continent of extremes; the low availability of liquid water and nutrients, extreme low temperatures and seasonally variable levels of solar radiation exert high selective pressures on ... [more ▼]

Antarctica is a continent of extremes; the low availability of liquid water and nutrients, extreme low temperatures and seasonally variable levels of solar radiation exert high selective pressures on organisms. Consequently, most life forms in the scarce ice-free regions which represent less than 1% of the surface area of the continent are microbial. Despite this, terrestrial microbial communities are poorly studied and the existing data are geographically focused on McMurdo dry valleys and volcanically active regions. Nunataks, mountain tops protruding through the ice sheets, occur along much of the East Antarctic coast and in the Transantarctic Mountains. Among them, several remained ice-free during Neogene and Pleistocene ice ages and thus may have acted as important refugia for terrestrial life. Here we present the results of a broad-scale survey of microbial biodiversity of ice-free regions in the western Sør Rondane Mountains (Dronning Maud Land (DML), East Antarctica). A total of 66 samples from eight different ice-free regions were selected to represent gradients in bedrock type (gneiss or granite), the macrobiotic content (presence or absence of moss, lichen and/or arthropods) and geographic location. All samples were subjected to both genetic fingerprinting (ARISA) and second generation sequencing (Illumina MiSeq 300PE) targeting the V1 -V3 variable regions of the 16S rRNA gene. Mock communities were included to benchmark the bioinformatics pipeline. Reads were processed using Usearch (Edgar 2010), clustered based on a 97 % similarity cutoff using Uparse (Edgar 2013)and identified using the GreenGenes training set. The specific conductivity, pH, water content, and total (TC),total organic (TOC) and inorganic (IC) carbon content were determined and used as explanatory variables in direct ordination analyses of both the ARISA and the Illumina data. The Illumina sequencing resulted in ~600.000 high quality sequences divided over ~3980 OTUs in 28 phyla and 219 genera. No significant differences in richness equaling the number of OTUs after standardization for the number of sequences per samples were observed between high, medium and low TOC content classes for the sequencing data. Redundancy Analysis revealed that bedrock type (granite or gneiss), water content, specific conductance, pH and TOC significantly shaped the bacterial community composition. The ARISA dataset, despite having a lower taxonomic resolution, showed very similar patterns and relationships with environmental data, among which bedrock type remained the most important parameter in explaining differences in community structure between the samples. As the gneiss is supposedly of granite origin, differences in community structure may be related to physical differences between both bedrock types and their weathering products. Preliminary cosmogenic analysis of Pb isotopes of gravel samples indeed suggest a predominantly local origin of the material, yet mixtures with exotic material cannot be excluded in samples from gneiss outcrops. We conclude that microbial community composition is primarily driven by mineralogical characteristics of weathering products in these poorly developed soils, while biotic influences are of secondary importance. [less ▲]

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See detailBIOGEOGRAPHIC PATTERNS IN ANTARCTIC LACUSTRINE PROKARYOTES
Tytgat, Bjorn; Verleyen, Elie; Sweetlove, Maxime et al

Poster (2015, September 07)

Amplified climate change, increased human activity and the introduction of alien species likely form the biggest threat to Antarctic terrestrial ecosystems through range size expansions and contractions ... [more ▼]

Amplified climate change, increased human activity and the introduction of alien species likely form the biggest threat to Antarctic terrestrial ecosystems through range size expansions and contractions, regional extirpation and impacts on ecosystem functions. Despite their crucial role in the functioning of Antarctic terrestrial ecosystems , little is known about the present -day diversity and biogeography of microorganisms such as prokaryotes and microeukaryotes in the Antarctic Biogeographic Realm. Furthermore, identification of the key processes underlying microbial biodiversity dynamics is essential to understand and predict the consequences of global change on Antarctic lacustrine ecosystems. We analysed bacterial biodiversity in a total of 152 lacustrine microbial mat samples, distributed over the three main Biogeographic regions in the Antarctic Realm, including continental Antarctica, Maritime Antarctica and the Sub-Antarctic Islands comprising the southern Indian Ocean Province (SIOP) and the southern Pacific Ocean Province (SPOP). We targeted the V1-V3 variable regions of the 16S rRNA gene. Amplicon sequencing was done on an Illumina PE300 MiSeq. Sequences were processed using Usearch and Uparse, Mothur and custom scripts for basic parsing. An OTU cut-off was defined at 97 % sequence similarity, and sequences were mapped against a local GreenGenes database. Downstream analyses were performed using several R packages. We obtained about three million high quality sequences, with an average length of 500 bp. Sequences belonged to 8237 OTUs, and were distributed over 51 phyla and 366 genera. In addition, 649 OTUs remained unclassified at the phylum level and 6263 at the genus level. Mean OTU richness differed strongly between the four biogeographic regions. The lakes from Maritime Antarctica had a higher richness than those from Continental Antarctica. Interestingly, in sub-Antarctica OTU richness was strongly variable, with Marion Island (SIOP) having the lowest and Macquarie Island (SPOP) having on average the highest diversity of all studied regions. Multivariate Analyses showed that microbial community composition varied between biogeographic regions, with Macquarie Island being most different from the other regions. Continental Antarctica, Maritime Antarctica and the lakes from the SIOP share many OTUs, both in the case of Cyanobacteria and other bacteria, but are also characterised by a considerable number of unique OTUs. Within Antarctica, some regions harbour distinct bacterial communities such as the lakes in Schirmacher Oasis, Dronning Maud Land, and those from the eastern and western part of the Antarctic Peninsula. [less ▲]

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See detailThe BCCM/ULC culture collection to conserve, document and explore the polar cyanobacterial diversity
Wilmotte, Annick ULg; Renard, Marine ULg; Kleinteich, Julia et al

Poster (2015, September 07)

In Polar Regions, Cyanobacteria represent key primary producers and are the main drivers of the food webs in a wide range of aquatic to terrestrial habitats. For example, they form benthic microbial mats ... [more ▼]

In Polar Regions, Cyanobacteria represent key primary producers and are the main drivers of the food webs in a wide range of aquatic to terrestrial habitats. For example, they form benthic microbial mats in lakes and soil crusts in terrestrial biotopes. They have adapted to their environment, and may present interesting features to survive freeze/thaw cycles, seasonally contrasted light intensities, high UV radiations, dessication and other environmental stresses. The BCCM/ULC public collection funded by the Belgian Science Policy Office since 2011 aims to gather a representative portion of the polar cyanobacterial diversity with different ecological origins (limnetic microbial mats, soil crusts, cryoconites, endoliths, etc.). The collection is available for researchers to study the taxonomy, evolution, adaptations to extreme environmental conditions, and genomic make-up. It presently includes 200 cyanobacterial strains, with 123 being of polar origin (catalogue: http://bccm.belspo.be/catalogues/ulc-catalogue-search). The morphological identification shows that the strains belong to the orders Synechococcales, Oscillatoriales, Pleurocapsales, Chroococcidiopsidales and Nostocales. The large diversity is also supported by the phylogenetic analyses based on the 16S rRNA sequences. This broad distribution makes the BCCM/ULC collection particularly interesting for phylogenomic studies. To this end, the sequencing of the complete genome of 16 selected strains is currently under way. In addition, cyanobacteria produce a wide range of secondary metabolites (e.g. alkaloides, cyclic and linear peptides, polyketides) with different bioactive potential (e.g. antibiotic, antiviral, anticancer, cytotoxic, genotoxic). Bioassays have shown antifungal activities of the cell extracts from strains Plectolyngbya hodgsonii ULC009 and Phormidium priestleyi ULC026. The potential of the polar strains to produce cyanotoxins and other secondary metabolites is currently being studied by ELISA, LC-MS and the detection of genes involved in their production. Due to the geographic isolation and the strong environmental stressors of the habitat, the exploration of these metabolites in Antarctic cyanobacterial strains seems promising for biotechnology or biomedical applications (Biondi et al. 2008). In summary, the BCCM/ULC public collection could serve as a Biological Resource Centre (OECD 2001) to conserve and document the biodiversity of polar cyanobacteria, as well as a repository for discovery of novel bioactive compounds. REFERENCES Biondi, N., Tredici, M., Taton, A., Wilmotte, A., Hodgson, D., Losi, D., & Marinelli, F. (2008) : Cyanobacteria from benthic mats of Antarctic lakes as a source of new bioactivities. Journal of Applied Microbiology, 105(1) : 105- 115 OECD (2001) Biological Resource Centres : Underpinning the Future of Life Sciences and Biotechnology. http://www.oecd.org/science/biotech/2487422.pdf [less ▲]

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See detailA next-generation protocol for the assessment of cyanobacterial diversity
Stelmach Pessi, Igor ULg; de Carvalho Maalouf, Pedro; Laughinghouse IV, Haywood Dail et al

Poster (2015, September)

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See detailBaseline data on the cyanobacterial diversity of Svalbard assessed by pyrosequencing
Laughinghouse IV, Haywood Dail; Stelmach Pessi, Igor ULg; Velázquez, David et al

Poster (2015, September)

Detailed reference viewed: 16 (2 ULg)
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See detailGenome sequencing of an endemic filamentous Antarctic cyanobacterium
Lara, Yannick ULg; Verlaine, Olivier ULg; Kleinteich, Julia et al

Poster (2015, August 03)

The strain Phormidium priestleyi ULC007 was isolated from a benthic mat located in a shallow freshwater pond in the Larsemann Hills (69°S), Western Antarctica. This strain belongs to a cyanobacterial ... [more ▼]

The strain Phormidium priestleyi ULC007 was isolated from a benthic mat located in a shallow freshwater pond in the Larsemann Hills (69°S), Western Antarctica. This strain belongs to a cyanobacterial cluster that appeared as potentially endemic (Taton et al. 2006). After obtaining an axenic isolate, we sequenced the genome of this strain in the frame of the BELSPO CCAMBIO project, in order to better understand the functioning, metabolism and adaptative strategies of cyanobacteria to the extreme Antarctic environment. [less ▲]

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See detailThe BCCM/ULC collection : a Biological Ressource Center for polar cyanobacteria
Wilmotte, Annick ULg; Renard, Marine ULg; Lara, Yannick ULg et al

Poster (2015, August 03)

In this study, during the 2013 MicroFun expedition, we sampled 72 locations around Svalbard including diverse biotopes such as glacial forefields, tundra soils, hot springs, soil crusts, microbial mats ... [more ▼]

In this study, during the 2013 MicroFun expedition, we sampled 72 locations around Svalbard including diverse biotopes such as glacial forefields, tundra soils, hot springs, soil crusts, microbial mats, wet walls, cryoconites, plankton and periphyton, in order to (1) assess the biodiversity of cyanobacteria around Svalbard, (2) verify the existence of biogeographical trends around the archipelago, and (3) compare these data with other polar (cold) areas, especially Antarctica. We used a pyrosequencing approach targeting cyanobacteria-specific 16S rRNA gene sequences to deeply study the cyanobacterial communities. [less ▲]

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See detailA next-generation approach to assess the cyanobacterial diversity and biogeography in the High Arctic (Svalbard)
Laughinghouse, Haywood Dail; Stelmach Pessi, Igor ULg; Velazquez, David et al

Poster (2015, August 03)

Polar ecosystems are extremely sensitive to global climate changes and human activities. Cyanobacteria are key photosynthetic organisms in these latitudes, due to their roles in soil aggregation, nitrogen ... [more ▼]

Polar ecosystems are extremely sensitive to global climate changes and human activities. Cyanobacteria are key photosynthetic organisms in these latitudes, due to their roles in soil aggregation, nitrogen fixation, carbon cycles, and secondary metabolite production, among others. Previous works indicate that different cyanobacterial taxa/communities have different impacts on the environment, in both biogeochemical cycles and bioactive compound productions. Furthermore, the presence of biogeographical patterns in microorganisms, as found in macroorganisms, is an ongoing debate. In this study, during the 2013 MicroFun expedition, we sampled 72 locations around Svalbard including diverse biotopes such as glacial forefields, tundra soils, hot springs, soil crusts, microbial mats, wet walls, cryoconites, plankton and periphyton, in order to (1) assess the biodiversity of cyanobacteria around Svalbard, (2) verify the existence of biogeographical trends around the archipelago, and (3) compare these data with other polar (cold) areas, especially Antarctica. We used a pyrosequencing approach targeting cyanobacteria-specific 16S rRNA gene sequences to deeply study the cyanobacterial communities. [less ▲]

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See detailContribution of cyanobacteria to the building of travertines in a calcareous stream
Wilmotte, Annick ULg; Golubic, Stjepko; Kleinteich, Julia et al

Poster (2015, August 03)

The ambient temperature travertine deposits of the calcareous Hoyoux River (Modave, Belgium) and several tributaries are organized and promoted by the filamentous cyanobacterium identified by its ... [more ▼]

The ambient temperature travertine deposits of the calcareous Hoyoux River (Modave, Belgium) and several tributaries are organized and promoted by the filamentous cyanobacterium identified by its morphotype and ecological properties as Phormidium cf. incrustatum. A combination of techniques was used to study this biotope: physico-chemical parameters and CO2 measurements, Scanning and Transmission Electron Microscopy, RAMAN microspectroscopy. A molecular diversity study with pyrosequencing of the cyanobacterial 16S rRNA is in progress. A potential candidate was isolated in culture. [less ▲]

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See detailDevelopment of cryopreservation methods for long-term preservation of cyanobacterial strains in the BCCM/ULC collection
Crahay, Charlotte ULg; Renard, Marine ULg; Mari, Maud et al

Poster (2015, August 03)

Long-term genetic and functional stability is a fundamental requirement for the maintenance of microorganisms and cryopreservation is the preferred method for the long-term storage of many micro-organisms ... [more ▼]

Long-term genetic and functional stability is a fundamental requirement for the maintenance of microorganisms and cryopreservation is the preferred method for the long-term storage of many micro-organisms, including cyanobacteria. The BCCM/ULC collection currently holds 200 cyanobacterial strains, but only 62 are cryo-preserved. The main limiting factors are the low levels of survival of some strains and the long periods required to recover from cryopreservation, and thus the inability to deliver rapidly cryopreserved strains to the user community. The devel-opment of improved cryopreservation protocols is therefore required for the future expansion and valorization of the collection. The BRAIN-be project PRESPHOTO (preservation of photosynthetic micro-algae in the BCCM collections) (www.presphoto.ulg.ac.be) aims to improve the preservation of cyanobacterial and diatoms in the BCCM/ULC and BCCM/DCG collections, respectively. [less ▲]

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See detailBasics on cyanobacterial genetics
Wilmotte, Annick ULg; Lara, Yannick ULg

Scientific conference (2015, July 03)

Detailed reference viewed: 54 (2 ULg)
See detail‘Ex-situ’ preservation and characterization of Antarctic cyanobacteria in the BCCM/ULC collection
Kleinteich, Julia ULg; Renard, Marine ULg; Simons, Véronique et al

Poster (2015, June 09)

The BCCM/ULC public collection of (sub)polar cyanobacteria is funded since 2011 by the Belgian Science Policy Office. An ISO9001 certificate was obtained for the public deposition and distribution of ... [more ▼]

The BCCM/ULC public collection of (sub)polar cyanobacteria is funded since 2011 by the Belgian Science Policy Office. An ISO9001 certificate was obtained for the public deposition and distribution of strains, as part of the multi-site certification for the BCCM consortium. BCCM/ULC is currently holding 160 public cyanobacterial strains and the catalogue is available on http://bccm.belspo.be/catalogues/ulc-catalogue-search. Continuous maintenance of living cultures, some of which are also cryopreserved, ensure the preservation and the possibility to rapidly deliver strains to clients for fundamental and applied research. The main holding of the collection concerns (sub)polar strains isolated from different biotopes and representative of a large taxonomic diversity. The molecular characterization is underway, on the basis of 16S rRNA and ITS sequences, but also Multiple Locus Sequence Analysis and genome sequencing. In addition, cyanobacteria are known to produce a range of secondary metabolites (e.g. alkaloides, cyclic and linear peptides, polyketides) with various bioactive potential. The presence of genes involved in the production of microcystin is currently studied by PCR, and analytical methods are used to confirm the toxin production. Due to the geographic isolation and the strong environmental stressors of the habitat, the exploration of these metabolites in Antarctic cyanobacterial strains seems especially promising for biotechnology or biomedical applications. [less ▲]

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See detailAn encapsulation-dehydration method for the long-term storage of cyanobacterial strains in the BCCM/ULC collection.
Crahay, Charlotte ULg; Mari, Maude; Wilmotte, Annick ULg

Poster (2015, May 13)

Long-term genetic and functional stability is a fundamental requirement for the maintenance of microorganisms. Cryopreservation is the preferred method for the long-term storage of many micro-organisms ... [more ▼]

Long-term genetic and functional stability is a fundamental requirement for the maintenance of microorganisms. Cryopreservation is the preferred method for the long-term storage of many micro-organisms, including cyanobacteria. The BCCM/ULC collection currently holds over 200 cyanobacterial strains as living cultures, but only 62 are maintained in a cryo-preserved state. The main limiting factors are the low levels of survival of some strains, as well as the long periods required to recover from cryopreservation, and thus the inability to rapidly deliver strains to clients.. The BRAIN-be project PRESPHOTO (preservation of photosynthetic micro-algae in the BCCM collections) (www.presphoto.ulg.ac.be) aims to improve the preservation of cyanobacterial and diatoms in the BCCM/ULC and BCCM/DCG collections, respec-tively. The encapsulation-dehydration is often considered as a promising alternative to the traditional cryopreservation method for recalcitrant microalgal strains. In this technique, cyanobacterial cultures are entrapped in calcium-alginate beads, osmotically dehydrated (traditionally with sucrose solutions), then evaporatively desiccated in a sterile air flow, or over silica gel and subsequently cryopreserved. In this study, the encapsulation-dehydration method was evaluated as potential long-term preservation technique of cyanobacterial strains. The effects of several factors on the viability of 4 strains have been investigated to determine which are the most important for the successful cryopreservation. In particular, several cryoprotectants (i.e. sucrose, PEG or mannitol), methods of beads dehydration (i.e. under a laminar flow or with silica gel) were tested. We have also compared storage at -70°C and in liquid nitrogen (-196oC). A pre-cultivation step in KCl was also tested for its ability to enhance desiccation tolerance. In addition, the use of alginate dissolution buffer following thawing was also considered. In the final phase of the project, the selected cryopreservation protocols will be tested on a large set of strains. In addition, an independent validation of the protocols will be also performed by both partners of the project (BCCM/DCG and the Culture Collection of Algae and Protozoa). [less ▲]

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See detailUnveiling Antarctic cyanobacterial diversity by 454 pyrosequencing
Stelmach Pessi, Igor ULg; de Carvalho Maalouf, Pedro; Laughinghouse IV, Haywood Dail et al

Scientific conference (2015, May)

Detailed reference viewed: 10 (2 ULg)
See detailPRESPHOTO project - Preservation of microalgae in the BCCM collections
Crahay, Charlotte ULg; Deprez, Karolien; Vanormelingen, Pieter et al

Poster (2015, May)

The implementation of reliable preservation technologies of the biological resources is crucial for the management of the Biological Ressources Centers. PRESPHOTO, a BRAIN.be project, aims to develop and ... [more ▼]

The implementation of reliable preservation technologies of the biological resources is crucial for the management of the Biological Ressources Centers. PRESPHOTO, a BRAIN.be project, aims to develop and optimize new and cost-effective preservation techniques of photosynthetic microalgae (diatoms and cyanobacteria) in the two BCCM collections, BCCM/DCG and BCCM/ULC. This is a critical factor for the future growth and valorisation of these collections. Firstly, the traditional two-step cryopreservation technique will be adapted to photosynthetic microalgae strains. In particular, we will examine the effects of the culture conditions, the type and concentration of cryoprotectants, and the preservation temperature on the survival of microalgae. The encapsulation/dehydration technique as alternative to the two-step cryopreservation method will be also evaluated. Moreover, an independent validation of the developed protocols will be performed by the Culture Collection of Algae and Protozoa (UK) (subcontractor). Secondly, we will perform genome resequencing of selected strains to investigate the genetic changes induced by different cryopreservation techniques. Finally, a high-quality genomic DNA bank will be established and validated. [less ▲]

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