An axenic cyclostat of Prochlorococcus PCC 9511 with a simulator of natural light regimes
Résumé
A cyclostat was designed for growing the oceanic oxyphotobacterium Prochlorococcus PCC 9511. Culture of this organism, known to bedifficult to grow, was mastered for a large volume. Prochlorococcusgrew well and axenic conditions were maintained for up to 15 days. Wedesigned an illumination system allowing a smooth bell-shaped irradiancecurve reaching almost 1000 μmol quanta m-2 s-1 tobe obtained. Cell division was strongly synchronised under theseillumination conditions, which were close to those found at low latitude inthe upper layer of ocean. The described device is particularly well suited tomake experiments requiring up to 6 L per day of well synchronised,exponentially-growing Prochlorococcus culture.