Molecular based winter to summer succession of unicellular eukaryotes in a temperate meso-eutrophic coastal system.
The sampling site was located at the SOMLIT (French Network of Coastal Observatories) station (50*40’75 N, 1*31’17 E, 20-25 m water depth) in the Eastern English Channel (EEC). This site was chosen, as the physical and hydrological properties encountered, are representative of the coastal water masses of the EEC. In situ sampling was conducted at three meters depth from February 25thst to June 9th 2009 at high tide. Samples for TAG pyrosequencing were collected by filtering 2.5 litres of seawater immediately after sampling with a serial filtration on 150 (to retain larger metazoa), 10, 3 and 0.6 *m, 47 mm nucleopore filters, using a peristaltic pump with a very low filtration pressure (15 rpm). The serial filtration was used in order to avoid filter clumping and minimise organism disruption. The filters were immediately frozen in liquid nitrogen and then stored at -80 *C until analysis. DNA extractions were carried out after pooling the 10, 3 and 0.6 *m filters.