1. Sampling during PROSOPE for studying Picophytoplankton Diversity Frédéric PARTENSKY, Dominique MARIE and Laurence GARCZAREK “Océanic Phytoplankton” Research Team Station Biologique de Roscoff CNRS et Université Paris 6

2. La Thalassa

3. Position of Stations during PROSOPE Long term stations

4. Connection by Netscape (not Explorer) http://www.obs-vlfr.fr/jgofs/html/ prosope/home.htm Ask Hervé Claustre for password PROSOPE web site

5. MeasurementDirectory name profiles number sample number Submit ted ValidatedData avail.Responsible Nitratesnut27 (12/05/2000) Raimbault Nitritesnut27 (12/05/2000) Raimbault Phosphatesnut17 (12/05/2000) Moutin Silicatesnut24Quéguiner Biogenic silicabiosi19Quéguiner Ironiron18Ridame, Guieu Alkalinityak20Begovic, Copin Salinitysal72Tailliez O2oxy60Begovic, Copin DMSdms770 Belviso DMSPdms7138Belviso HIAChiac108Sciandra Pigmentspig7018 Ras, Claustre, Marty Flow Cytometrycyto100Marie Phytoplanktonphyto22Quéguiner Ciliatescilates125Dolan COP, NOP, POPpom21Raimbault TOCtoc35337Sempéré NOD, PODmod15337Raimbault Particulate matter Absorption apm70Oubelkheir, Claustre

6. Sampling during PROSOPE Flow cytometry Short term stations : 1 profile 0-200 m & 1 deep profile (virus/bact.) Long term stations (MIO, DYF) : 1 profile 0-200 m every 3h for 4 days Sampling for Diversity  DNA : pre-filtration on 3µm, filtration 2-5L on Supor 0.45 µm, freezing in DNA/RNA buffer  Diversity Prochlorococcus : Filtration 2 L, filter cut in 2 and frozen  HPLC : filter 3 µm (Stations 1, 3, 5, 9, MIO, DYF)  TEM : 5-6 grids/depth (Stations 1, 3, 5, 9, MIO, DYF)  Cultures : 4/depth (2 < 0,6 µm in P2+/-NO3; 2 < 3 µm in K/10 or K/100)  Station UPW : 2 depths  Station 1 : 2 depths (3 & 60 m)  Station 3 : 6 depths (5, 25, 55, 80, 95, 110 m)  Station 5, MIO, 7, 8, 9, DYF : 5 depths  Station DYF : 5 depths + détail Chl maximum (45, 50, 55, 60 et 65 m) Sampling for nutrient status (D. Scanlan, A. Post) UPW, 2, 4, 6, MIO, +/- DYF : 3 depths

7. Automatic sampler for collecting samples during transit Sampler Electronic control After Jacquet et al., 1998

8. Concentration of Picophytoplankton along the nutrient gradient from Station 1 to MIO

9. Variation of integrated concentrations of picoplankton over the nutrient gradient

10. A Preliminary Study of the Diversity of Natural Populations of Prochlorococcus Vertical profiles Unpublished data D. Marie, D. Tailliez, P. Raimbault

11. Genetic Characterization of Prochlorococcus Strains using PCR-RFLP with pcb as a Marker Gene Fluorescence (Relative Units) 0 1 400450500550 Wavelength (nm) Ecotypes LL SS120 NATL2 Ecotypes HL TAK9803-2 (HLII) MED4 (HLI) DV-Chl aDV-Chl b MED4 SS120 TAK9803-2 NATL2 after Garczarek et al. (2000) Proceed. Natl. Acad. Sci. USA M

12. A Preliminary Study of the Diversity of Natural Populations of Prochlorococcus PCR-RFLP M1 5 25 55 80 95 110 M2 5 25 55 65 95 M1 5 30 50 90 150 M2 St. 3 St. 5 St. 6 ? Unpublished data L. Garczarek, A. Dufresne and F. Partensky 0,1 0,2 0,3 0,4 0,5 0,6 0,7 ?

13. 5 25 55 80 95 110 5 25 55 65 95 5 30 50 90 150 0,2 0,4 0,6 0,8 G3 = HL Génotypes G4 = LL (deep) Kb St. 3 St. 5 St. 6 G5 = LL ? (mid depth) G2 = HL A Preliminary Study of the Diversity of Prochlorococcus Interpretation of PCR-RFLP G1 = HL