References of "Wilmotte, Annick"
     in
Bookmark and Share    
Full Text
See detailA Phylogenomic analysis of the origin of plastids
Cornet, Luc ULg; Javaux, Emmanuelle ULg; Wilmotte, Annick ULg et al

Conference (2014, June 24)

Cyanobacteria are a morphologically diverse phylum, with their first occurrence dating from the Precambrian. Oxygenic photosynthesis appeared in this group during the same geological period. Several ... [more ▼]

Cyanobacteria are a morphologically diverse phylum, with their first occurrence dating from the Precambrian. Oxygenic photosynthesis appeared in this group during the same geological period. Several publications have established, without any doubt, that plastids (both primary and complex) form a monophyletic ensemble emerging from Cyanobacteria. However, the exact position of plastids within Cyanobacteria is still uncertain, with several recent papers leading to very different hypotheses. Here we present a phylogenomic analysis of the origin of plastids. Our study takes advantage of all the available genomes and thus represents the best taxonomic sampling seen so far: 140 genomes of Cyanobacteria, 101 genomes of plastids and 27 outgroups taken in Melainabacteria and Chloroflexi. It results in an analysis using state-of-the-art methods (e.g., orthology assessment using USEARCH and OrthoMCL, phylogenetic inference using CAT and CAT-GTR models) based on more than 160 protein alignments totalizing over 20,000 unambiguously aligned amino acids. To confirm our results, we performed gene jackknife inferences and gene reconciliation analyses on the same dataset. We expect that out approach accounts for potential phylogenetic artefacts due to changes in the evolutionary process having occurred when the guest cyanobacterium became an endosymbiont and eventually a plastid. Meanwhile, we improve the phylogeny of Cyanobacteria per se, notably because of the presence of Melainabacteria in our dataset. [less ▲]

Detailed reference viewed: 36 (4 ULg)
Full Text
See detailAssessment of bioinformatic pipelines for the analysis of 454 pyrosequencing data using artificial cyanobacterial communities
Stelmach Pessi, Igor ULg; De Carvalho Maalouf, Pedro; Laughinghouse IV, Haywood ULg et al

Poster (2013, November 27)

The field of microbial ecology has undergone a revolution with the advent of next-generation sequencing (NGS) technologies, which revealed a higher microbial diversity than what was previously observed ... [more ▼]

The field of microbial ecology has undergone a revolution with the advent of next-generation sequencing (NGS) technologies, which revealed a higher microbial diversity than what was previously observed. The possibility of analyzing tens to hundreds of thousands sequences in a single sequencing run has provided information on rare taxa that could constitute an important fraction of microbial communities. However, this comes with the cost of relatively high error rates for individual reads, which can lead to overestimation of diversity due to the generation of spurious Operational Taxonomic Units (OTUs) consisting of erroneous sequences. Therefore, a correct assessment of microbial diversity using NGS relies on robust bioinformatic tools in order to correct for PCR and sequencing biases. Here we report on community structures recovered for two artificial cyanobacterial communities applying three commonly used and two recently published bioinformatic pipelines. This pilot study was made in the frame of the BELSPO project CCAMBIO. Artificial communities were constructed using DNA isolated from 22 cyanobacterial strains from the BCCM/ULC Polar Cyanobacteria Collection (http://bccm.belspo.be/about/ulc.php). DNA was extracted from individual cultures and pooled at equal (community Art1) or tiered (community Art2) concentrations. The V3-V4 hypervariable region of the 16S rRNA gene was amplified by PCR using primers 359F and 781Ra/781Rb [Nübel et al (1997) Appl Environ Microbiol 63: 3327-3332], and amplicons were sequenced on a 454 GS FLX Titanium platform. Data was demultiplexed and submitted to five bioinformatic pipelines for quality control of reads, removal of chimeric sequences and Operational Taxonomic Units (OTUs) clustering: (I) “shhh.flows (450 flows)”, (II) “shhh.flows (360-720 flows)” and (III) “Sliding Window (Q35, 50 bp)”, using MOTHUR according to Schloss et al (2011) [Schloss et al (2011) PLOS One 6: e27310]; (IV) “fastq_maxee” and (V) “fastq_truncqual”, using UPARSE according to Edgar (2013) [Edgar (2013) Nat Methods 10: 996-998]. Average sequence length varied considerably among pipelines, with pipeline I generating shorter reads (220 bp in average) and pipelines IV and V longer reads (370 bp). The number of OTUs obtained in each pipeline also varied significantly. While 22 and 21 OTUs were obtained for pipelines IV and V, respectively, pipelines I-III generated a surprisingly high number of OTUs (199, 317 and 289, respectively). Despite differences in the number of OTUs, the relative abundance of each reference strain did not differ significantly between pipelines. Overall, community structures observed using the UPARSE protocol (pipelines IV and V) were the most consistent with the expected results. These findings show the importance of assessing the performance of different bioinformatic pipelines using artificial communities, in order to reduce the effects of PCR and sequencing errors, which can lead to distorted community structures estimates. [less ▲]

Detailed reference viewed: 81 (9 ULg)
Full Text
See detailBioregionalisation and biodiversity of Cyanobacterial communities in East- Antarctic lakes
De Carvalho Maalouf, Pedro ULg; Stelmach Pessi, Igor ULg; Verleyen, Elie et al

Poster (2013, July)

On the Antarctic continent, ice-free regions represent only 0.3% of the total surface area. In these regions, cyanobacteria are one of the dominant phototrophs and primary producers, forming cohesive ... [more ▼]

On the Antarctic continent, ice-free regions represent only 0.3% of the total surface area. In these regions, cyanobacteria are one of the dominant phototrophs and primary producers, forming cohesive benthic mats in lakes and other aquatic habitats. Using a recent compilation of published biodiversity data from Antarctica and the sub-Antarctic islands in combination with physical factors and expert-defined bioregions, Terauds et al. (2012) identified 15 biologically distinct ice-free Antarctic Conservation Biogeographic Regions (ACBRs). However, the degree and nature of bioregionalisation in Antarctic cyanobacterial communities is still largely unknown. In this study, cyanobacterial diversity was analysed using Denaturating Gradient Gel Electrophoresis (DGGE) on a partial 16S rRNA sequence (ca 400 bp) in 50 microbial mats originating from five of the seven ACBRs identified in East Antarctica. Comparison of the sequences with those available in GenBank was carried out to assess the geographical distribution of the taxa on both local and global scales. A total of 35 Operational Taxonomic Units (OTUs, group of sequences with more than 98.5% sequence similarity) was obtained for all samples. Moreover, the taxonomic turnover between the five ACBRs was relatively low, as 69.5% of the OTUs were present in 2 or 3 bioregions. Consistent with previous findings, a large proportion (37%) of the OTUs was restricted to the “cold biosphere”, and 17% appeared potentially endemic to the Antarctic continent. These results suggest that the patterns of bioregionalisation in East Antarctic cyanobacteria are different than the ACBR scheme. Therefore, it would be useful to study the microbial bioregionalisation in more detail and using less conserved molecular taxonomic markers than the 16S rRNA gene, such as the ITS region. Moreover, since DGGE only provides information on the dominant taxa in microbial assemblages, a high-throughput screening is currently being performed. [less ▲]

Detailed reference viewed: 52 (16 ULg)
Full Text
See detailBiodiversity studies in Open-Top Chambers in continental Antarctica
Mano, Marie-José ULg; Namsaraev, Zorigto; Obbels, Dagmar et al

Poster (2013, July)

Open Top Chambers are passive warming systems used to experimentally assess the effect of climate change on terrestrial ecosystems, and they were used in several Antarctic regions to study the response of ... [more ▼]

Open Top Chambers are passive warming systems used to experimentally assess the effect of climate change on terrestrial ecosystems, and they were used in several Antarctic regions to study the response of biotic communities. In the BELSPO BELDIVA project, OTCs were used in continental Eastern Antarctica, where environmental conditions are very extreme. In January 2010, 8 Open-Top Chambers (OTC) were installed in four ice-free regions of the Sör Rondane Mountains, namely on the Utsteinen ridge, the Tanngarden granite outcrop, the Teltet nunatak and the fourth nunatak of the Pingvinane range. [less ▲]

Detailed reference viewed: 70 (7 ULg)
Full Text
See detailHuman impacts on Antarctic ecosystems: do not forget the microorganisms!
Hughes, Kevin; Verleyen, Elie; Vyverman, Wim et al

Conference (2013, July)

The tiny and microscopic creatures that are the permanent inhabitants of the Antarctic continent are often overlooked in environmental impact assessments and when new management and protection strategies ... [more ▼]

The tiny and microscopic creatures that are the permanent inhabitants of the Antarctic continent are often overlooked in environmental impact assessments and when new management and protection strategies are designed. This lack of consideration is probably due to their small size and the need of sophisticated molecular methods to study their diversity, evolution and geographic distribution. However, considerable progress has been made in the field of molecular diversity in the last two decennia, and is still ongoing for Antarctic bacteria, cyanobacteria, protists, fungi, etc. Recent studies have shown the presence of highly diverse microbial communities and the existence of species endemic to Antarctic in some taxonomic groups. With the emergence of High Throughput Sequencing methodologies that are able to detect ‘rare’ taxa, it becomes crucial to find Antarctic locations that have not yet been impacted by human presence. These ‘pristine’ areas are essential to serve as reference sites and allow to distinguish the true Antarctic organisms from the imported ones. Indeed, recent studies have shown that humans unintentionally disperse their own microbial flora but may also spread organisms from other locations. In the extreme biotopes with a reduced diversity that are currently found in Antarctica, such contaminations might have a profound impact. It is important to raise the awareness of scientists, environmental managers and policy makers about the necessity to single out some areas that are kept untouched, or where stringent biosecurity measures are taken. The purpose is not to hinder scientific research, but to weigh carefully, when exploring a new area, the importance of the acquired piece of knowledge in relation to the possibility of hindering future microbiological research. Some parallels with other fields of research are interesting to consider. Archeologists are used to keeping some parts of the explored caves untouched because they foresee that technological progress will allow better analyses in future. The COSPAR Panel on Planetary Protection makes recommendations to avoid the contamination of other planets with microbes from Earth, which would obscure any discovery of extraterrestrial indigenous life forms. These examples illustrate the essential need to integrate the delineation of reference areas for future analyses in the design and execution of scientific research. In fact, the Madrid Protocol foresees the possibility to designate ‘inviolate areas’ (Annex V, Article 3), though this tool has rarely been used. It would be useful if scientists of all disciplines would reflect how to use this management option. [less ▲]

Detailed reference viewed: 44 (10 ULg)
See detailThe diversity and tolerance to osmotic stress of East Antarctic filamentous Cyanobacteria
Obbels, Dagmar; Verleyen, Elie; Tytgat, Bjorn et al

Poster (2013, July)

Filamentous cyanobacteria are keystone species in Antarctic lake ecosystems; they are the basis of the simple foodwebs, play a crucial role in biogeochemical cycling and form the structure of benthic ... [more ▼]

Filamentous cyanobacteria are keystone species in Antarctic lake ecosystems; they are the basis of the simple foodwebs, play a crucial role in biogeochemical cycling and form the structure of benthic microbial mats which act as habitats for other prokaryotic and (micro-eukaryotic biota. Despite this, little is known about their diversity, adaptation and survival strategies in the extreme Antarctic conditions. We studied the uncultivated prokaryotic diversity using a 454 metagenomic analysis at the 16S rRNA level (V1-V3 region) in Continental Antarctic lakes situated along a conductivity gradient (0.014-142.02 mS/cm). The quality and length of the amplicons was analyzed with a custom-made Mothur pipeline and the resulting sequences were mapped against the Greengenes database, which includes CyanoDB. Almost 27% of the sequences could be assigned to the phylum of the cyanobacteria. The most abundant cyanobacteria in the dataset belonged to the genera Microcoleus, Leptolyngbya, Pseudanabaena, Nodularia and Phormidum. Some 16S rRNA types (at the 97% similarity level), such as sequences related to Leptolynbya antarctica, were present in both freshwater and hypersaline lakes. In order to further investigate this distribution, we isolated filaments of Leptolyngbya from seven lakes with conductivities ranging between 26.8 mS/cm and 0.038 mS/cm. The complete 16S rRNA and ITS genes of the isolates were subsequently sequenced. We found several 16S types related to different lineages of filamentous cyanobacteria in the seven lakes that were supported by ITS data. Two 16S types, belonging to a Leptolyngbya antarctica and Leptolyngbya sp., were each present in two different freshwater lakes. Two different 16S types, both belonging to Leptolynbya antarctica were present in a freshwater and hypersaline lake, which indicates a high ‘intraspecific’ molecular diversity. In order to better understand the adaptation and/or wide tolerance to osmotic stress, we are currently performing ecophysiological experiments with these isolates aimed at assessing the potential local adaptation of these strains to conductivity and desiccation. [less ▲]

Detailed reference viewed: 51 (13 ULg)
Full Text
Peer Reviewed
See detailA cultivation-independent approach for the genetic and cyanotoxin characterization of colonial cyanobacteria
Lara, Yannick ULg; Lambion, Alexandre ULg; Menzel, Diana et al

in Aquatic Microbial Ecology (2013), 69

To bypass the constraint of cyanobacterial strain isolation and cultivation, a combination of whole genome amplification (WGA) and enzyme-linked immunoassay (ELISA) for microcystin toxins (MCs) was tested ... [more ▼]

To bypass the constraint of cyanobacterial strain isolation and cultivation, a combination of whole genome amplification (WGA) and enzyme-linked immunoassay (ELISA) for microcystin toxins (MCs) was tested on individual colonies of Microcystis and Woronichinia, taken directly from aquatic environments. Genomic DNA of boiled cells was amplified by multiple strand displacement amplification (MDA), followed by several specific PCR reactions to characterize the genotype of each colony. Sequences of 3 different housekeeping genes (ftsZ, gltX, and recA), of 3 MC biosynthesis genes (mcyA, mcyB, and mcyE), and the Internal Transcribed Spacer (ITS) were analyzed for 11 colonies of Microcystis. MCs were detected and quantified by ELISA in 7 of the 11 Microcystis colonies tested, in agreement with the detection of mcy genes. Sequence types (ST) based on the concatenated sequences of housekeeping genes from cyanobacterial colonies from Belgian water bodies appeared to be endemic when compared to those of strains described in the literature. One colony appeared to belong to a yet undiscovered lineage. A similar protocol was used for 6 colonies of the genus Woronichinia, a taxon that is very difficult to cultivate in the laboratory. The 16S rRNA sequences of 2 colonies were obtained and were quasi identical to that of W. naegeliana 0LE35S01. For one Woronichinia colony, the mcyE PCR gave a non-specific PCR product. The corresponding amino acid sequence was 50% identical to a Microcystis ketoacyl carrier protein transferase. This approach for the simultaneous detection and quantification of MCs with mcy genotyping, at single colony level, offers potential for the ecotoxicological characterization of environmental populations of cyanobacteria without the need for strain isolation and culture. [less ▲]

Detailed reference viewed: 68 (13 ULg)
Full Text
Peer Reviewed
See detailLate Holocene changes in cyanobacterial community structure in maritime Antarctic lakes
Fernandez-Carazo, Rafael; Verleyen, Elie; Hodgson, Dominic A et al

in Journal of Paleolimnology (2013), 50

Despite the dominance of cyanobacteria in polar freshwater aquatic ecosystems, little is known about their past biodiversity and response to climate and environmental changes. We explored the use of light ... [more ▼]

Despite the dominance of cyanobacteria in polar freshwater aquatic ecosystems, little is known about their past biodiversity and response to climate and environmental changes. We explored the use of light microscopy of microfossils, high performance liquid chromatography of the fossil pigment composition and denaturing gradient gel electrophoresis of fossil 16S rRNA genes to study past and present-day differences in cyanobacterial community structure in response to climate changes in two adjacent maritime Antarctic lakes with contrasting depths (4 and 26 m) and light climates. Light microscopy was of limited use because of degradation of cell structures. Fossil cyanobacterial pigment concentrations were below the detection limits of our method in several sediment samples in the deep lake, but abundant and diverse inthe sediment core from the shallow pond, probably as a consequence of increased light availability and/or a more diverse and abundant benthic cyanobacterial flora. Total carotenoid and chlorophyll concentrations were highest in both lakes between ca. 2,950 and 1,800 cal yr BP, which coincides with the late Holocene climate optimum recognised elsewhere in maritime Antarctica. Cyanobacterial molecular diversity was higher in the top few centimeters of the sediments in both lakes. In deeper sediments, the taxonomic turnover of cyanobacteria appeared to be relatively small in response to past climate anomalies in both lakes, underscoring the broad tolerance of cyanobacteria to environmental variability. This, however, may in part be explained by the low taxonomic resolution obtained with the relatively conserved 16S rRNA gene and/or the preferential preservation of particular taxa. Our results highlight the potential of fossil DNA in lake sediments to study colonization and succession dynamics of lacustrine cyanobacteria and warrant further investigation of the factors that affect preservation of cyanobacterial DNA. [less ▲]

Detailed reference viewed: 39 (17 ULg)
Full Text
See detailPristine Antarctica: Threats and Protection
Hughes, K.A.; Cary, S.C; Cowan, D.A et al

in Antarctic Science (2013), 25(01), 1

Molecular technologies have shown unequivocally that much of Antarctica’s biological value and diversity lies in its microbiota. Microbial diversity varies greatly over small spatial scales, and there may ... [more ▼]

Molecular technologies have shown unequivocally that much of Antarctica’s biological value and diversity lies in its microbiota. Microbial diversity varies greatly over small spatial scales, and there may be high levels of endemism in some groups. At the 2012 SCAR Open Science Conference, .70% of scientific presentations by terrestrial biologists concerned microbiology, and the topic features prominently in the newly approved SCAR biology programmes State of the Antarctic Ecosystem (AntEco) and Antarctic Thresholds - Ecosystem Resilience and Adaptation (AnT-ERA). The future looks bright for Antarctic microbiology - but some significant threats need to be addressed and resolved. [less ▲]

Detailed reference viewed: 12 (3 ULg)
Full Text
See detailAntarctic cyanobacterial diversity: how important are the geographical and ecological factors?
De Carvalho Maalouf, Pedro ULg; Lambion, Alexandre ULg; Gillard, Benjamin et al

Conference (2012, October 31)

On the Antarctic continent, cyanobacteria produce conspicuous benthic microbial mats in lakes, from the coastal regions to the mountains (till 84°S). However, little is known about theirl biodiversity in ... [more ▼]

On the Antarctic continent, cyanobacteria produce conspicuous benthic microbial mats in lakes, from the coastal regions to the mountains (till 84°S). However, little is known about theirl biodiversity in comparison with other regions of the world. The BelSPO project AMBIO aimed to test whether (i) microbial communities are structured by the same factors as those shaping communities of macroorganisms, and (ii) endemism among cyanobacteria does exist. We have analyzed the cyanobacterial biodiversity in a variety of aquatic habitats from the three main biogeographical regions (Continental, Maritime Antarctica and the Sub-Antarctic) and determined the ‘baseline’ data needed to understand the contribution of various processes that are responsible for the distribution patterns. [less ▲]

Detailed reference viewed: 25 (5 ULg)
Full Text
Peer Reviewed
See detailElucidation of the gas vesicle gene clusters in cyanobacteria of the genus Arthrospira (Oscillatoriales, Cyanophyta) and correlation with ITS phylogeny
Miklaszewska, Magdalena; Waleron, Malgorzata; Morin, Nicolas et al

in European Journal of Phycology (2012), 47

The genus Arthrospira comprises filamentous cyanobacteria in which the trichomes form an open helix and contain gas vacuoles. The gas vesicle gene cluster of five Arthrospira strains was amplified by PCR ... [more ▼]

The genus Arthrospira comprises filamentous cyanobacteria in which the trichomes form an open helix and contain gas vacuoles. The gas vesicle gene cluster of five Arthrospira strains was amplified by PCR and sequenced. The genes are organized in one operon, in the order gvpA1–gvpC1–gvpA2–gvpC2–gvpA3–gvpC3–gvpN. In Arthrospira sp. strain PCC 8005, the genes gvpJ, gvpK, gvpV and gvpW were also identified. Each of the three copies of gvpA encodes a protein of 71 amino acids. In the case of gvpC, there are two different length variants. Each of the two shorter genes, gvpC1 and gvpC2, encodes a putative protein of 151 amino acids, while the longer one, gvpC3, codes for a putative protein of 284 residues. The amino acid sequences of GvpC1 and GvpC2 are identical to the N-terminal part of GvpC3. In spite of the presence of stop codons downstream of gvpC1 and gvpC2, the deduced amino acid sequences in these regions are highly similar to the C-terminal part of GvpC3 (residues 160 to 229). The GvpC1, GvpC2 and GvpC3 proteins contain contiguous repeats of 33 amino acids as previously reported for other cyanobacteria. The sequences of the gvpA1, gvpC1, gvpA2 and gvpC2 genes were not found in the genome data of Arthrospira sp. PCC 8005, A. maxima CS-328, and A. platensis NIES-39 as a result of incomplete assembly. The genes gvpN and gvpJ located downstream of gvpC3, encode putative proteins of 394 and 127 amino acids, respectively. The deduced amino acid sequences of gvpK, gvpV and gvpW contain 151, 112 and 227 residues, respectively. The analysis of gvp sequences of five strains of Arthrospira revealed the presence of polymorphic positions, which distinguished the strains in agreement with their previous assignments to ITS clusters I and II. This is the first report of gvp genes in members of the genus Arthrospira. [less ▲]

Detailed reference viewed: 72 (2 ULg)
Full Text
See detailAntarctic Microbial BIOdiversity : the importance of geographical versus ecological factors
Obbels, Dagmar; De Carvalho Maalouf, Pedro ULg; De Wever, Aaike et al

Poster (2012, July)

Detailed reference viewed: 6 (1 ULg)
Full Text
See detailAntarctic Microbial BIOdiversity : the importance of geographical versus ecological factors
Obbels, Dagmar; De Carvalho Maalouf, Pedro ULg; De Wever, Aaike et al

Poster (2012, July)

Antarctica is a prime region to test whether microbes have a biogeography and to study their metacommunity dynamics, because (i) it is isolated from the other continents, (ii) its extreme environmental ... [more ▼]

Antarctica is a prime region to test whether microbes have a biogeography and to study their metacommunity dynamics, because (i) it is isolated from the other continents, (ii) its extreme environmental conditions allow microorganisms to dominate its ecosystems, and (iii) lacustrine and terrestrial habitats occur isolated in a matrix of ice and ocean. We compiled a large set of samples from benthic microbial mats from Antarctic lakes in different ice-free regions and used a polyphasic approach to study their microbial biodiversity by combining morphological characterization of diatoms with molecular techniques such as Denaturing Gradient Gel Electrophoresis (green algae and cyanobacteria), 454 pyrosequencing and cultivation (prokaryotes). [less ▲]

Detailed reference viewed: 30 (3 ULg)
Full Text
See detailClimate change simulation in continental Antarctica using Open-Top Chambers
Mano, Marie-José ULg; Namsaraev, Zorigto; Gorodetskaya, Irina et al

Poster (2012, July)

In continental Antarctica, the environnmental conditions are extreme and only microbial organisms can withstand them. Currently, the majority of OTCs experiments are being held in Maritime Antarctica but ... [more ▼]

In continental Antarctica, the environnmental conditions are extreme and only microbial organisms can withstand them. Currently, the majority of OTCs experiments are being held in Maritime Antarctica but it would be interesting to have such data for the continental part of Eastern Antarctica. To monitor the response of the microbial communities to local simulations of climate change, 8 Open-Top Chambers (OTC) were installed close to the Princess Elisabeth station, in the Sor Rondane Mountains in January 2010. They are located on the Utsteinen ridge, the Tanngarden granite outcrop, the Teltet nunatak and the fourth nunatak of the Pingvinane range. In each location, two OTCs and a control area were established. Temperature and humidity loggers were installed inside the OTCs and outside, in the control areas, to estimate the environmental changes induced by the OTCs. [less ▲]

Detailed reference viewed: 32 (5 ULg)
Full Text
See detailOut of sight, out of mind ? Diversity of microscopic organisms as an overlooked criterion for conservation purposes
Mano, Marie-José ULg; De Carvalho, Pedro; Verleyen, Elie et al

Conference (2012, July)

The network of ASPAs (Antarctic Specially Protected Areas) that is presently under construction in the frame of the Committee for Environmental Protection of the Antarctic Treaty is intended to protect ... [more ▼]

The network of ASPAs (Antarctic Specially Protected Areas) that is presently under construction in the frame of the Committee for Environmental Protection of the Antarctic Treaty is intended to protect "outstanding environmental, scientific, historic, aesthetic or wilderness values, any combination of those values, or ongoing or planned scientific research" (http://www.ats.aq/e/ep_protected.htm). When the Madrid Protocol was signed, twenty-one years ago, the knowledge on the biodiversity of tiny and microscopic organisms was much less extensive and molecular methods for biodiversity assessments were only in their infancy. The majority of the permanent inhabitants of Antarctica are, however, essentially microscopic. [less ▲]

Detailed reference viewed: 38 (4 ULg)
Full Text
See detailDiversity of the cyanobacterial communities from the Sør Rondane Mountains (Eastern Antarctica)
Mano, Marie-José ULg; Namsaraev, Zorigto; Fernandez, Rafael et al

Poster (2012, July)

The new Belgian “Princess Elisabeth” research station was built in 2009 and is located 200 km inland in the Western part of the Sør Rondane Mountains (Eastern Antarctica). The BELSPO projects ANTAR-IMPACT ... [more ▼]

The new Belgian “Princess Elisabeth” research station was built in 2009 and is located 200 km inland in the Western part of the Sør Rondane Mountains (Eastern Antarctica). The BELSPO projects ANTAR-IMPACT and BELDIVA aimed to evaluate the diversity and the distribution patterns of the microorganisms from different types of habitats in a radius of 50 km around the Belgian station. These data will serve to follow future anthropogenic and climatic impacts on these communities. Here, we focus on the diversity of cyanobacteria. [less ▲]

Detailed reference viewed: 19 (2 ULg)
Full Text
Peer Reviewed
See detailThe MicroH2 project:an association of four laboratories to improve theknowledge on biohydrogen production precesses
Beckers, Laurent ULg; Calusinska, Magdalena ULg; Hamilton, Christopher ULg et al

Poster (2012, June 04)

This poster presents a collaborative research project (MicroH2) held at the University of Liège (Belgium) since 2007 (www.microh2.ulg.ac.be) and involving four different research groups. The project aims ... [more ▼]

This poster presents a collaborative research project (MicroH2) held at the University of Liège (Belgium) since 2007 (www.microh2.ulg.ac.be) and involving four different research groups. The project aims to develop a center of excellence in the fields of photo- and dark- biohydrogen production. Our studies contribute to improve the knowledge of the processes involved in the microbiological production of hydrogen, from a fundamental and practical point of view. Some results are highlighted here. The research concerning photofermentation focuses on the interactions between respiration, photosynthesis and H2-producing pathways in algal microorganisms, by using mitochondrial mutants and genetically modified strains with modified ability for hydrogen production [1-2]. To study the metabolism of the hydrogen production by anaerobic bacteria, pure cultures and defined consortia are used and their production of biogas and soluble metabolites is measured. Moreover, we have developed and optimized molecular tools, like quantitative RT-PCR and FISH, to monitor the variations of bacterial populations in novel bioreactors for hydrogen production [3-4]. We have also mined the complete genomes of Clostridium spp. for putative hydrogenase genes and found a large diversity of them [5]. [less ▲]

Detailed reference viewed: 49 (12 ULg)
Full Text
See detailTHREE NEW BCCM PUBLIC COLLECTIONS ON DIATOMS, MYCOBACTERIA AND CYANOBACTERIA
Rigouts, Leen; Vanormelingen, Pieter; Vyverman, Wim et al

Poster (2012, June)

Detailed reference viewed: 29 (0 ULg)