Quantifying Cyanothece growth under DIC limitation

Computational and Structural Biotechnology Journal

Pascal Claquin¹  Takako Masuda²  Curtis Deutsch³  Jan Červený⁴  Marie Vancová⁴  Eva Kotabová⁵  Keisuke Inomura⁵  Sophie Rabouille⁶  Meri Eichner⁶  David J. Suggett⁶  Gabrielle Armin⁶  Susanne Stephan⁷  Gábor Bernát⁸  Tomáš Zavřel⁹  Ondřej Prášil^1,10 

[1] Balaton Limnological Research Institute, Eötvös Loránd Research Network (ELKH), Tihany, Hungary;Corresponding author at: Graduate School of Oceanography, University of Rhode Island, 215 S Ferry Road, Narragansett, Rhode Island 02882, USA.;Department Experimental Limnology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Stechlin, Germany;Department of Adaptive Biotechnologies, Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic;Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, USA;Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czech Republic;Laboratoire de Biologie des ORganismes et Ecosystèmes Aquatiques (BOREA), UMR 8067, Muséum National d'Histoire Naturelle, CNRS, IRD Sorbonne Université, Université de Caen Normandie, Normandie Université, Esplanade de la Paix, F-14032 Caen, France;Laboratory of Electron Microscopy, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences and Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic;Sorbonne Université, CNRS, Laboratoire d’Océanographie Microbienne, LOMIC, F-66650 Banyuls-sur-mer, France;University of Technology Sydney, Climate Change Cluster, Faculty of Science, Ultimo, NSW 2007, Australia;

关键词: Cyanothece;    DIC;    CO2;    Nitrogen fixation;    Nitrate;    Diurnal cycle;   

DOI  :  

来源: DOAJ

【 摘 要 】

The photoautotrophic, unicellular N2-fixer, Cyanothece, is a model organism that has been widely used to study photosynthesis regulation, the structure of photosystems, and the temporal segregation of carbon (C) and nitrogen (N) fixation in light and dark phases of the diel cycle. Here, we present a simple quantitative model and experimental data that together, suggest external dissolved inorganic carbon (DIC) concentration as a major limiting factor for Cyanothece growth, due to its high C-storage requirement. Using experimental data from a parallel laboratory study as a basis, we show that after the onset of the light period, DIC was rapidly consumed by photosynthesis, leading to a sharp drop in the rate of photosynthesis and C accumulation. In N2-fixing cultures, high rates of photosynthesis in the morning enabled rapid conversion of DIC to intracellular C storage, hastening DIC consumption to levels that limited further uptake. The N2-fixing condition allows only a small fraction of fixed C for cellular growth since a large fraction was reserved in storage to fuel night-time N2 fixation. Our model provides a framework for resolving DIC limitation in aquatic ecosystem simulations, where DIC as a growth-limiting factor has rarely been considered, and importantly emphasizes the effect of intracellular C allocation on growth rate that varies depending on the growth environment.

【 授权许可】

Unknown