Electron & Biomass Dynamics of Cyanothece Under Interacting Nitrogen & Carbon Limitations

Author(s):Show less -

Rabouille, Sophie ^{[1, 2]} ; Campbell, Douglas A. ^{[3, 4]} ; Masuda, Takako ^[3] ; Zavrel, Tomas ^[5] ; Bernat, Gabor ^{[3, 6]} ; Polerecky, Lubos ^[7] ; Halsey, Kimberly ^[8] ; Eichner, Meri ^{[3, 9]} ; Kotabova, Eva ^[3] ; Stephan, Susanne ^{[10, 11]} ; Lukes, Martin ^[3] ; Claquin, Pascal ^[12] ; Bonomi-Barufi, Jose ^[13] ; Lombardi, Ana Teresa ^[14] ; Cerveny, Jan ^[5] ; Suggett, David J. ^[15] ; Giordano, Mario ^{[16, 3]} ; Kromkamp, Jacco C. ^{[17, 18]} ; Prasil, Ondrej ^[3]

Affiliation:Show less -

^[1] Sorbonne Univ, CNRS, LOV, Villefranche Sur Mer - France

^[2] Sorbonne Univ, CNRS, LOMIC, Banyuls Sur Mer - France

^[3] Czech Acad Sci, Inst Microbiol, Ctr Algatech, Trebon - Czech Republic

^[4] Mt Allison Univ, Sackville, NB - Canada

^[5] Global Change Res Inst CAS, Dept Adapt Biotechnol, Brno - Czech Republic

^[6] Balaton Limnol Inst, Ctr Ecol Res, Klebelsberg Kuno U 3, H-8237 Tihany - Hungary

^[7] Univ Utrecht, Dept Earth Sci, Utrecht - Netherlands

^[8] Oregon State Univ, Dept Microbiol, Corvallis, OR 97331 - USA

^[9] Max Planck Inst Marine Microbiol, Bremen - Germany

^[10] Leibniz Inst Freshwater Ecol & Inland Fisheries, Alten Fischerhutte 2, Stechlin - Germany

^[11] Berlin Inst Technol TU Berlin, Dept Ecol, Ernst Reuter Pl 1, Berlin - Germany

^[12] Univ Caen Basse Normandie, CNRS, UMR BOREA 8067, MNHN, IRD 207, Caen - France

^[13] Univ Fed Santa Catarina, Dept Bot, Ctr Ciencias Biol, Florianopolis, SC - Brazil

^[14] Univ Fed Sao Carlos, Sao Carlos - Brazil

^[15] Univ Technol Sydney, Climate Change Cluster, Fac Sci, Ultimo, NSW - Australia

^[16] Univ Politecn Marche, Dipartimento Sci Vita & Ambiente, Ancona - Italy

^[17] Univ Utrecht, Utrecht - Netherlands

^[18] NIOZ Royal Netherlands Inst Sea Res, Utrecht - Netherlands

• Document type: Journal article
• Source: FRONTIERS IN MICROBIOLOGY; v. 12, APR 9 2021.
• Web of Science Citations: 0

Abstract

Marine diazotrophs are a diverse group with key roles in biogeochemical fluxes linked to primary productivity. The unicellular, diazotrophic cyanobacterium Cyanothece is widely found in coastal, subtropical oceans. We analyze the consequences of diazotrophy on growth efficiency, compared to NO3--supported growth in Cyanothece, to understand how cells cope with N-2-fixation when they also have to face carbon limitation, which may transiently affect populations in coastal environments or during blooms of phytoplankton communities. When grown in obligate diazotrophy, cells face the double burden of a more ATP-demanding N-acquisition mode and additional metabolic losses imposed by the transient storage of reducing potential as carbohydrate, compared to a hypothetical N-2 assimilation directly driven by photosynthetic electron transport. Further, this energetic burden imposed by N-2-fixation could not be alleviated, despite the high irradiance level within the cultures, because photosynthesis was limited by the availability of dissolved inorganic carbon (DIC), and possibly by a constrained capacity for carbon storage. DIC limitation exacerbates the costs on growth imposed by nitrogen fixation. Therefore, the competitive efficiency of diazotrophs could be hindered in areas with insufficient renewal of dissolved gases and/or with intense phytoplankton biomass that both decrease available light energy and draw the DIC level down. (AU)

• FAPESP's process: 17/12450-1 - 10th International GAP Meeting - Aquatic Productivity in the -omics era
• Grantee: Ana Teresa Lombardi
• Support Opportunities: Research Grants - Meeting - Abroad