Recent trends in bio-technological research in deep-sea vents in the Azores region

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1 Recent trends in bio-technological research in deep-sea vents in the Azores region Ricardo Serrão Santos Departamento de Oceanografia e Pescas Universidade dos Açores OPEN DAYS 2007 The Atlantic as a factor of competitiveness: Innovation towards the growth of the maritime sector Brussels 11 October 2007

2 Oceanic Ridges with Hydrothermal vents The most extensive volcanic systems of the Planet: km. Medium depth: m. Spreading rate: 0.25 a 20 cm/year.

3 The dark blue Atlantic region and its rift harbor great variety of seamounts with cold coral reefs and gardens and massive sponges, active underwater volcanoes and chemosynthetic ecosystems with extreme life forms (extremophyles).

5 Oceanic Ridges with Hydrothermal Vents Extreme life conditions: No light High pressure Seismic and volcanic activity Low levels of oxygen Temperature gradients up to + 350ºC Low ph Fluids highly rich in heavy metals

6 Deepsea hydrothermal vents are probably one of the most toxic environments on earth. Toxicity is due to the fact that the fluids emitted show high levels of concentration of heavy metals, as also as radionuclides which may damage DNA and big concentrations of the toxic hydrogen sulphide. Menez-Gwen Lucky Strike Rainbow Seawater 850 m 1500 m 2500 m ph H 2 S (mm) ~0 CO 2 (mm) < 16 - CH 4 (mm) ~0 Ag (nm) Cd (nm) < Cl (mm) Co (µm) < 2 < 2 13 < 2 Cu (µm) < 2 < Fe (µm) < Mn (µm) Ni (µm) < 2 < 2 3 < 2 Si (mm) <0.2 Zn (µm) < 2 < Douville, Charlou et al. (2002), Charlou, Donval et al. (2000), Charlou, Donval et al. (2002)

During chemosynthesis the hydrogen sulphide is the source of energy.

7 Symbiosis: The animals benefit from the bacteria which transform CO 2 in organic matter. At the same time bacteria benefit from protection. During chemosynthesis the hydrogen sulphide is the source of energy. It is utilised by free living bacteria or is absorbed by the invertebrate hosts and transported to the symbionts.

8 The paradox pf hydrothermal ecosystems Abundant biomasses (+ de 20 kg/m 2 ) Endemic biodiversity Fast growth rate conciliated with Photos: IFREMER High toxicity (i.e. elements of radioactive radon + heavy metals: Cd, Hg, Cn, Pb, Zn, Fe, Ag)

9 Temporal window frames that cruises cannot provide!????????

10 Menez Gwen

11 LabHorta Research Station for the experimental study of deep sea organisms. R/V Arquipélago e R/V Atalante meet at the Menez Gwen site for exchange of scientists, biological samples and deployment of cages.

12 LabHorta Research Station for the experimental study of deep sea organisms. Cages deployed at 1000 m of depth are filled up with mussels with the help of the French ROV VICTOR 6000 or the manned submersible Nautile and recovered during the following months by the R/V Arquipélago. They are then brought to Horta, within 16 h, for acclimatization and experimental studies in LabHorta.

13 LabHorta Large Scale Facility for the experimental study of deep sea organisms. Deployment Retrieval of cages of cages in autumn, during summer winter and campaigns spring

14 LabHorta Research Station for the experimental study of deep sea organisms. The mussels Bathymodiolus azoricus and their symbiont bacteria are maintained for several months in insulated aquaria, supplied with methane and hydrogen sulfide, for experimental studies Pressurized aquaria IPOCAMP and Chemical regulation system (SYRENE) for in vivo studies under pressure conditions, in LabHorta.

Bathymodiolus azoricus physiological adaptations to extreme

proteins involved in adaptation to extreme environments.

animals to overcome the toxic and stress effects resulting

Study of the genome and the use of genes involved in the

15 Bathymodiolus azoricus physiological adaptations to extreme environments Proteomics Genomics Large scale study of proteins involved in adaptation to extreme environments. In the case of metallothionein proteins they are used by vent animals to overcome the toxic and stress effects resulting from exposure to cadmium and mercury. Study of the genome and the use of genes involved in the repair of damaged DNA Reproduction Immunology Studies on immunoreaction. Studies of reproduction in captivity

tissues. Cells are visualized with dark coloured nuclei.

16 Development of biomarkers to evaluate Bathymodiolus fitness in acclimatized aquaria: apoptosis (programmed cell death) Experimentally induced cell death (apoptosis) in gill tissues. Cells are visualized with dark coloured nuclei. Gill tissues with no apoptotic cells (no cell death in mussels kept in aquaria for 15 days) Raul Bettencourt 2006 unpublished

17 Resistance to toxic effect from the environment: exploring new natural capacities to repair DNA lesions. Bathymodiolus azoricus can survive with higher levels of DNA lesions comparing to its close shallow water relative, the mussel Mytilus edulis. Pruski & Dixon 2003 Aquatic Toxicology

18 Evidence of seasonal reproduction of B. azoricus in the wild A C Spt Spc adg Spg Spc B D Pvo Og Ov adg Pvo (A) 7 August; male, beginning of development; (B) 7 August, female, beginning of development; (C) 1 September, maturing male; (D) 1 September, maturing female; (E) 1 February, male spawning; (F) 1 February, female, mature oocytes. E Spz F Gvn OcMI D. Dixon et al InterRidge News D. Dixon et al Journal of the Marine Biological Association of the UK

Reproduction of B. azoricus maintained in aquaria for one year. Oocyte Spermatozoa Egg dividing Bathymodiolus Embryo with aproxim. azoricus80μm.

a) Histological section of male gonad. b) D. Dixon Histological et al. insection press of JMBA female gonad.

19 Reproduction of B. azoricus maintained in aquaria for one year. Oocyte Spermatozoa Egg dividing Bathymodiolus Embryo with aproxim. azoricus80μm. kept in Released aquaria since and fertilized Abril in LabHorta Samples processed aquarium at in 7 C temp January and atmosphere. a) Histological section of male gonad. b) D. Dixon Histological et al. insection press of JMBA female gonad. c) Dividing egg, retrieved from aquarium on January 17. d) Abnormal diving egg; SD, spermatic duct; SPZ, spermatozoa; O, oocyte; (bar 50 μm). Ana Colaço et al Journal of Experimental Biology and Ecology

Environmental acquisition of symbionts under laboratory conditions supports the horizontal symbiont transmission hypothesis as opposed to the trans-ovarial transmission. A) B.

20 Environmental acquisition of symbionts under laboratory conditions supports the horizontal symbiont transmission hypothesis as opposed to the trans-ovarial transmission. A) B. azoricus kept in sea water without hydrogen sulfide (H2S), during 30 days: absence of symbionts in vacuoles. C) After 15 days of re-acclimatization in sea water supplied with hydrogen sulfide, bacteria from the environment are internalized D) A large number of sulfur-oxidizing symbionts (Sb) are internalized through pores on the apical surfaces (arrows) of epithelial cells Eniko Kadar et al Journal of Experimental Marine Biology & Ecology

21 Hemolymph (blood) cells from B. azoricus can release cytotoxic substances that can destroy other cells. Cytotoxic factors released from hemocytes Elimination of cells Raul Bettencourt et al in press, Marine Ecology

22 No bio-magnification of heavy metals through the food chain. Ana Colaço et al Deep-Sea Research No evidence of Hg biomagnification (Menez Gwen) Same pattern was observed for Cu and Zn (Lucky Strike & Rainbow). Ana Colaço et al 2006, Chemosphere

23 Antibacterial factors isolated from B. azoricus. Protein extracts from gills (G) and hemocytes (H) exhibit antibacterial properties against some bacterial strains (e.g Bacillus subtillis) Raul Bettencourt et al in press Marine Environmental Research

24 Discovery of the tumour suppressor gene p53 in Bathymodiolus azoricus p53 binds to the DNA molecule and regulates the expression of cancer genes. Raul Bettencourt et al in prep.

25 Results attained Host-symbiont interactions Behavioral responses to mercury exposures. Reproduction and development - gametogenesis in captivity. Mutagenicity and repair mechanisms associated DNA lesions Anti-oxidative, stress responses Stable isotopes: analysis of several nutritional regimes Loss and acquisition of parasites Innate immune responses (anti-bacterial, inflammatory genes, transcription factors, cell-cell signaling molecules)

Hydrothermal vents from the Azores

Hydrothermal vents from the Azores Ana Colaço Center of IMAR from University of Azores Departement of Oceanography and Fisheries 1 Hydrothermal vents are zones of fluid expulsion from the sea floor, normally