|Huete-Ortega M, Di Marcello M, Iglesias-Gonzalez J, Gnaiger E (2020) High-resolution respirometry for chloroplast and mitochondrial bioenergetics in Chlamydomonas reinhardtii ― towards biotechnology exploitations. MitoFit Preprint Arch doi:10.26124/mitofit:ea20.algaeurope.0001.|
Abstract: Version 1 (v1) 2020-11-30 doi:10.26124/mitofit:ea20.algaeurope.0001
Chloroplast and mitochondrial bioenergetic control of algal growth and metabolite production is necessary to maintain metabolic integrity. In contrast to mammalian cells, algal mitochondria express alternative oxidases (AOX), which divert electron transfer from coenzyme Q (Q) away from cytochrome c oxidase (Complex IV, CIV) . In algae, therefore, we distinguish between respiration through the Q-AOX and Q-CIV branches of the electron transfer system. A better understanding of the contribution of both branches to mitochondrial dark respiration is required to optimize algal biomass and metabolite production for biotechnological purposes. High-resolution respirometry (HRR; Oroboros O2k) is widely used to assess mitochondrial respiration and other bioenergetic parameters in the biomedical field of mitochondrial and cell research . In our interdisciplinary study, we introduced a new method of studying oxygen kinetics [3,4] for the partitioning of dark respiration between the Q-AOX and Q-CIV branches in Chlamydomonas reinhardtii grown for biomass and lipid production . This method is based on the distinct oxygen affinities of these enzymes. In addition, the multimodal approach of the Oroboros O2k was extended using the novel PhotoBiology-Module of the NextGen-O2k for determining the maximum light-saturated and inorganic carbon-saturated photosynthesis rates [6,7]. This methodology allows for increasing our current knowledge of the bioenergetics of chloroplasts and mitochondria, which is of particular importance for biotechnological exploitations. This communication is part of the NextGen-O2k project that has received funding from the European Union’s Horizon 2020 research and innovation program under the grant agreement No 859770.
• Keywords: photosynthesis, respiration, microalgae, high-resolution respirometry, O2 kinetics, NextGen • Bioblast editor: Huete-Ortega Maria
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Preprints for Gentle Science
Labels: MiParea: Instruments;methods
Preparation: Intact cells Enzyme: Complex IV;cytochrome c oxidase Regulation: Oxygen kinetics Coupling state: ROUTINE Pathway: Other combinations HRR: Oxygraph-2k, NextGen-O2k
Preprints; NextGen-O2k, Algae, Dark respiration, Photosynthesis, PB-Module, MitoFit 2021.5 PB