Inorganic Carbon Assimilation in Cyanobacteria: Mechanisms, Regulation, and Engineering

Chapter 1 Inorganic Carbon Assimilation in Cyanobacteria: Mechanisms, Regulation, and Engineering Martin Hagemann, Martin Hagemann University of Rostock, Institute of Biosciences, Department of Plant Physiology, A.-Einstein-Str. 3, Rostock D-18059, GermanySearch for more papers by this authorShanshan Song, Shanshan Song University of Rostock, Institute of Biosciences, Department of Plant Physiology, A.-Einstein-Str. 3, Rostock D-18059, GermanySearch for more papers by this authorEva-Maria Brouwer, Eva-Maria Brouwer University of Rostock, Institute of Biosciences, Department of Plant Physiology, A.-Einstein-Str. 3, Rostock D-18059, GermanySearch for more papers by this author Martin Hagemann, Martin Hagemann University of Rostock, Institute of Biosciences, Department of Plant Physiology, A.-Einstein-Str. 3, Rostock D-18059, GermanySearch for more papers by this authorShanshan Song, Shanshan Song University of Rostock, Institute of Biosciences, Department of Plant Physiology, A.-Einstein-Str. 3, Rostock D-18059, GermanySearch for more papers by this authorEva-Maria Brouwer, Eva-Maria Brouwer University of Rostock, Institute of Biosciences, Department of Plant Physiology, A.-Einstein-Str. 3, Rostock D-18059, GermanySearch for more papers by this author Book Editor(s):Jens Nielsen, Jens NielsenSearch for more papers by this authorSang Lee, Sang LeeSearch for more papers by this authorGregory Stephanopoulos, Gregory StephanopoulosSearch for more papers by this authorPaul Hudson, Paul HudsonSearch for more papers by this author First published: 30 April 2021 https://doi.org/10.1002/9783527824908.ch1Citations: 1 AboutPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShareShare a linkShare onFacebookTwitterLinked InRedditWechat Summary The availability of inorganic carbon (Ci), the substrate for cyanobacterial photosynthetic carbon assimilation, changed in long-term and short-term timescales. Therefore, cyanobacteria evolved an efficient carbon-concentrating mechanism (CCM) to respond to fluctuating Ci concentrations. The CCM includes different Ci uptake systems and the carboxysome, a prokaryotic CO2-enriched compartment encapsulating RubisCO and carbonic anhydrase. The Ci assimilation is regulated at different levels. Particularly, Ci uptake systems are subject to transcriptional regulation, which is fine-tuned by metabolic signals such as 2-oxoglutarate and 2-phosphoglycolate displaying the cell's carbon/nitrogen ratio. In contrast, Ci assimilation pathways seem to be mainly regulated at post-transcriptional levels comprising, for example, protein phosphorylation and redox regulation of enzyme activities. The application of cyanobacteria as green cell factories initiated many attempts to enhance Ci assimilation to improve product titers. Furthermore, plants are being engineered that will express the cyanobacterial CCM to improve growth and productivity in crops. Finally, photorespiration, the 2-phosphoglycolate salvage pathway, has been investigated in cyanobacteria, where it contributes to the acclimation to different Ci amounts. Different strategies to optimize photorespiration, especially to reduce its carbon loss and energy demand, have been proposed and are tested in cyanobacteria. Hence, our knowledge on the mechanisms and regulation of cyanobacterial Ci assimilation increasingly contributes to develop a sustainable production of energy and feedstock. Citing Literature Cyanobacteria Biotechnology RelatedInformation