Cyanobacterial energy storage is tightly controlled by circadian clock

0365075 - ÚVGZ 2012 eng C - Conference Paper (international conference)
Červený, Jan
Cyanobacterial energy storage is tightly controlled by circadian clock.
[Congress of the International Society for Applied Phycology /4./. Halifax (CA), 19.06.-24.06.2011]
Institutional research plan: CEZ:AV0Z60870520
Keywords : circadian oscillator * Cyanothece * model * glycogen * biotechnology
Subject RIV: EH - Ecology, Behaviour
http://arl-repository.lib.cas.cz/nusl/UEK-B/cav_un_epca-0365075_01.pdf

The metabolism of the unicellular, nitrogen fixing cyanobacterium Cyanothece sp. exhibits strong circadian regulation that has profound implications on biomass composition. The optical density measured at 735 nm was stable during rapid morning chlorophyll accumulation, and then, increased in the early afternoon towards a peak, followed by a rapid decline towards the late night steady state. We propose that these dynamics largely reflect accumulation and subsequent consumption of glycogen granules. To explore the dynamics of the link between respiration and circadian oscillations, we extrapolated an earlier model of the KaiABC oscillator from Synechococcus el. to Cyanothece sp. Measured respiratory activity correlated strongly in its timing and proportions with the modeled accumulation of the KaiB4 complex, which marks the late afternoon phase of the circadian clock. These dramatic metabolic events are shown to limit optimal harvest time in biotechnological applications to a particular day phase.
Permanent Link: http://hdl.handle.net/11104/0200411