Overexpression of bifunctional fructose-1,6-bisphosphatase/sedoheptulose-1,7-bisphosphatase leads to enhanced photosynthesis and global reprogramming of carbon metabolism in Synechococcus sp. PCC 7002

Overexpression of Sedoheptulose-1,7-Bisphosphatase Enhances Photosynthesis in Chlamydomonas reinhardtii and Has No Effect on the Abundance of Other Calvin-Benson Cycle Enzymes

“…We first tested the four SBP1-overexpressing transformants for improved growth. As elevated SBPase activity has resulted in improved growth particularly under high light and high CO 2 conditions (Miyagawa et al, 2001;Lefebvre et al, 2005;Tamoi et al, 2006;Ichikawa et al, 2010;Gong et al, 2015;Ogawa et al, 2015;Driever et al, 2017;De Porcellinis et al, 2018), we chose to grow the transformants under mixotrophic conditions with acetate in the medium at a light intensity of 150 µmol photons m −2 s −1 (our standard growth light intensity is 40 µmol photons m −2 s −1 ). Part of the acetate apparently is converted into CO 2 by Krebs cycle activity in the mitochondria and available to Rubisco in the chloroplast (Johnson and Alric, 2012;Polukhina et al, 2016).…”

“…SBPase catalyzes the irreversible dephosphorylation of sedoheptulose-1,7-bisphosphate (SBP) to sedoheptulose-7phosphate (S7P). Accordingly, the overexpression of SBPase alone (Lefebvre et al, 2005;Tamoi et al, 2006;Feng et al, 2007;Rosenthal et al, 2011;Fang et al, 2012;Ding et al, 2016;Driever et al, 2017;Simkin et al, 2017a) or of the cyanobacterial bifunctional SBPase/FBPase (BiBPase) (Miyagawa et al, 2001;Yabuta et al, 2008;Ichikawa et al, 2010;Gong et al, 2015;Ogawa et al, 2015;Kohler et al, 2017;De Porcellinis et al, 2018) resulted in marked increases in photosynthesis and biomass yields in tobacco, lettuce, Arabidopsis thaliana, wheat, tomato, rice, soybean, in the cyanobacterium Synechococcus, and in the microalgae Euglena gracilis and Dunaliella bardawil.…”

A Brassica napus Reductase Gene Dissected by Associative Transcriptomics Enhances Plant Adaption to Freezing Stress

“…Moreover, RCA enhances growth and photosynthesis under moderate heat stress conditions (Kurek et al, 2007;Kumar et al, 2009). However, overexpression of SBPASE improves sugar accumulation and enhanced photosynthesis efficiency (Miyagawa et al, 2001;Feng et al, 2007;De Porcellinis et al, 2018). In the present study, PSII was severely repressed during freezing treatment, whereas the BnTR1 transgenic Arabidopsis plants still exhibited higher Fv/Fm level compared to WT ( Figure 5A).…”

Toward Enhanced Fixation of CO2 in Aquatic Biomass: Focus on Microalgae

“…For example, overexpression of sedoheptulose-1,7-bisphosphatase or sedoheptusole-1,7/fructose-1,6-bisphosphatase increased glycerol accumulation in Dunaliella bardawil and wax esters in Euglena gracilis (Fang et al, 2012;Ogawa et al, 2015). In Synechococcus, the overexpression of the bifunctional enzyme led to a large adjustment of C metabolism, enhancing photosynthetic C fixation while decreasing respiration (De Porcellinis et al, 2018). These findings prove that modifying the expression of specific CBB enzymes shall contribute to an improved C fixation and cell productivity.…”

“…A path to improve C fixation thus relies on optimization of CBB enzymes' stoichiometry to ease the regeneration of RuBP. Mutants harboring modified amounts of Rubisco, sedoheptulose-1,7-bisphosphatase, fructose-1,6-bisphosphatase (the latter two as a bifunctional enzyme in cyanobacteria), fructose 1,6-bisphosphate aldolase or transketolase, have been obtained both in eukaryotic algae and cyanobacteria (Fang et al, 2012;Ogawa et al, 2015;Liang and Lindblad, 2016;Yang et al, 2017;De Porcellinis et al, 2018). As described above for TLA mutants, manipulated abundance of CBB enzymes led to variable results, according to the species and to the specific enzyme under investigation.…”