Coccolith production through coccolithophore growth experiment

Experiment measuring mass of a single coccolithophore cell every minute for near 9h. The coccolithophore is a Gephyrocapsa huxleyi culture strain RCC1216 from the Roscoff Culture Collection. A multi-well plate containing a low-density culture of calcifying cells grown in K/2 culture medium (Keller et al., 1987) was placed on the stage of an inverted microscope Leica DMi8 with a Smarteck GC3851MP camera, installed in a climate-controlled room (20°C) at the Biological Station of Roscoff and illuminated with large-spectrum white LED lights with an intensity of ca. 100 µmol.m-2.s-1. The coccolithophore produced 9 coccoliths during the experiment. The mass of individual coccospheres (in pg CaCO3) was estimated from their birefringence quantified from the images (Beaufort et al., 2014). Each produced coccolith was heavier than the previous one. The cell was most probably in G1 interphase and thus growing during the experiment.