Effects of light and circadian clock on growth and chlorophyll accumulation of Nannochloropsis gaditana

© 2014 Phycological Society of America.

Bibliographische Detailangaben
Veröffentlicht in:Journal of phycology. - 1966. - 50(2014), 3 vom: 18. Juni, Seite 515-25
1. Verfasser: Braun, Regina (VerfasserIn)
Weitere Verfasser: Farré, Eva M, Schurr, Ulrich, Matsubara, Shizue
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2014
Zugriff auf das übergeordnete Werk:Journal of phycology
Schlagworte:Journal Article Nannochloropsis blue light chlorophyll circadian clock clock entrainment growth light-dark photobioreactor photosystem II red light
Beschreibung
Zusammenfassung:© 2014 Phycological Society of America.
Circadian clocks synchronize various physiological, metabolic and developmental processes of organisms with specific phases of recurring changes in their environment (e.g. day and night or seasons). Here, we investigated whether the circadian clock plays a role in regulation of growth and chlorophyll (Chl) accumulation in Nannochloropsis gaditana, an oleaginous marine microalga which is considered as a potential feedstock for biofuels and for which a draft genome sequence has been published. Optical density (OD) of N. gaditana culture was monitored at 680 and 735 nm under 12:12 h or 18:6 h light-dark (LD) cycles and after switching to continuous illumination in photobioreactors. In parallel, Chl fluorescence was measured to assess the quantum yield of photosystem II. Furthermore, to test if red- or blue-light photoreceptors are involved in clock entrainment in N. gaditana, some of the experiments were conducted by using only red or blue light. Growth and Chl accumulation were confined to light periods in the LD cycles, increasing more strongly in the first half than in the second half of the light periods. After switching to continuous light, rhythmic oscillations continued (especially for OD680 ) at least in the first 24 h, with a 50% decrease in the capacity to grow and accumulate Chl during the first subjective night. Pronounced free-running oscillations were induced by blue light, but not by red light. In contrast, the photosystem II quantum yield was determined by light conditions. The results indicate interactions between circadian and light regulation of growth and Chl accumulation in N. gaditana
Beschreibung:Date Completed 26.07.2016
Date Revised 18.03.2016
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1529-8817
DOI:10.1111/jpy.12177