Diel variations of carbohydrates and neutral lipids in N-sufficient and N-limited cyclostat cultures of Isochrysis sp. - Inria - Institut national de recherche en sciences et technologies du numérique Accéder directement au contenu
Article Dans Une Revue Journal of Phycology Année : 2012

Diel variations of carbohydrates and neutral lipids in N-sufficient and N-limited cyclostat cultures of Isochrysis sp.

Résumé

The goal of this study was to investigate the time response of two major carbon (C) reserves, respectively neutral lipids (NL) and total carbohydrate (TC), in the Haptophyte Isochrysis sp. growing in nitrogen (N)-sufficient or N-starved conditions and under light:dark (L:D) cycles. Experiments were carried out in a cyclostat culture system that allowed the following of the dynamics of the main cell compounds at both hourly and daily time scales. Under N-sufficient conditions, the L:D cycles cause the population to be synchronized, with most of the cells dividing at the beginning of the dark period. The C-specific growth rate was maximal around midday and negative during the dark period due to respiration processes. NL and TC both accumulated during the day and consumed during the night. We showed that NL and TC are highly dynamic compounds, as more than three quarters of NL and TC accumulated during the light period were consumed during the dark period. In contrast to NL, phospholipid and glycolipid to C ratios remained quite stable during the light/dark cycles. The major effect of N starvation on the NL and TC dynamics was to uncouple their diel variations from the L:D cycle, in two different ways depending on their respective role during short-term acclimation. Whereas the TC per cell ratio increased rapidly to reach a stable value in response to N starvation, NL per cell continued to oscillate, but with a pattern out of phase with the L:D cycle.

Dates et versions

hal-00848420 , version 1 (26-07-2013)

Identifiants

Citer

Thomas Lacour, Antoine Sciandra, Amélie Talec, Patrick Mayzaud, Olivier Bernard. Diel variations of carbohydrates and neutral lipids in N-sufficient and N-limited cyclostat cultures of Isochrysis sp.. Journal of Phycology, 2012, 48 (4), pp.966-975. ⟨10.1111/j.1529-8817.2012.01177.x⟩. ⟨hal-00848420⟩
263 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More