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ECB9/1960
MICROMAT : Science and Biotechnology meet in the cold
De Wit R1, Dyer P2, Genilloud O3, Göttlich4, E, Hodgson D5, de Hoog S6, Jones B7, Laybourn-Parry J2, Marinelli F8,
Stackebrandt E9, Swings J10, Vyverman W10, Wilmotte A11
1. Biological Oceanography, University of Bordeaux 1, 33120 Arcachon, France. 2. Biological Sciences, University of Nottingham, Loughborough LE12 5RD, UK. 3. Merck-Sharp-
Dohme Espana, 28027 Madrid. 4. IWW, 45476 Mülheim, Germany. 5. British Antarctic Survey, CB3 OET Cambridge, UK. 6. Centraalbureau voor Schimmelcultures, 3740 AG Baarn,
Netherlands. 7. Genencor, PO Box 218, 2300 AE Leiden, Netherlands. 8. Biosearch Italia SPA, 21040 Gerenzano (VA), Italy. 9. DSMZ, 38124 Braunschweig, Germany. 10.
Microbiology/Protistology, University of Gent, 9000 Gent, Belgium. 11. Botany B22, University of Liège, 4000 Liège, Belgium.
Gloeocapsa sp. (cyanobacteria) from
lake Gentner, Larsemann Hills
(ULG, B)
Phialophora sp. (fungi) from lake
Fryxell, Dry Valleys
(IWW, DE)
A surface sediment core containing finelylayered microbial mats from lake Nella in the
Larsemann Hills.
(BAS, UK)
A small saline lake (24.4 mS/cm) in the
Rauer Islands, near Larsemann Hills
(BAS, UK)
Sample FR1A (bacteria) from
lake Fryxell, Dry Valleys
(RUG/A, B)
Amphora veneta (diatom), from
lake Grovness, Larsemann Hills
(RUG/B, B)
Vorticella sp. (protozoa) from lake
Fryxell, Dry Valleys
(U-Nottingham, UK)
Chlorella sp. (green alga) from
lake LH42, Larsemann Hills
(RUG/B, B)
Robotic station for HTS screening
(Biosearch, I)
Summary:
A recently started EC-biotech project concerning the biodiversity of microbial mats in the lakes of Antarctica is gathering scientists who will study the diversity of cultivated and 'yetto-be cultivated ’ microorganisms (bacteria, fungi, protists) and three biotechnology companies who will screen strains isolated by their partners for novel cold-tolerant enzymes and
bioactive compounds.
Materials and Methods:
Frozen and/or refrigerated material was sent from three locations in Antarctica (Dry Valleys, Larseman Hills, Vestfold Hills). For bacteria, the samples were homogeneized and plated
on different media, incubated at several temperatures. For other microorganisms, subsamples were fixed for microscopic observation. Other subsamples were plated out, diluted or
enriched in liquid culture. Different temperatures were used for the incubations, to recover both psychrophiles and psychotrophs. In addition, the Benthic Gradient Chamber (1) was
used with various gradients (H2S, O2, light) at 5°C to serve as enrichment culture and to try to maintain the mats. Frozen subsamples will be used later for molecular analyses of the
biodiversity, based on rDNA sequences. Isolated strains will be screened by HTS for pharmaceutical compounds and cold-adapted enzymes.
Overview and discussion of results:
Preliminary results show that the level of diversity is different for each type of microorganism. In the case of bacteria, a single mat sample yields several hundreds of putatively
different colony types. For cyanobacteria, fungi and photosynthetic and heterotrophic protists, a high diversity can only be achieved by studying a wide range of lakes with different
environmental conditions (salinity, pH,...). Isolation and characterization of pure strains are currently being carried out.
Conclusions:
Preliminary observations show that the biodiversity of microorganisms is conspicuous in the microbial mats of Antarctic lakes from three different locations and with different
environmental conditions. This is in contrast with the plancton in these lakes, which has low species diversity. Carotenoids and UV-protective pigments are abundant in bacterial cells
and cyanobacterial sheaths. For the diatoms, it seems that lakes recently exposed to the atmosphere (due to deglaciation), contain a different flora than lakes emerged from under the
ice sheet for more than 1000’s of years.
References:
(1) Pringault et al., 1996, FEMS Microbiology Ecology 20, 237-250
BIOTECH
Life Sciences and Technologies
Biotechnology Programme
(1994-1998)
http://europa.eu.int/comm/dg12/biot1.html
Contact person in Biotech Unit:
[email protected]
Biotechnology unit - DG XII
European Commission
rue de la Loi, 200 / wetstraat, 200
B-1049 Bruxelles / Brussel
Belgique / België
Fax number: +32-2-299.18.60
E-mail: [email protected]