Recent Posts

Single-nucleus sequencing reveals transition from C3 to C4 photosynthesis

Sometime in the Cretaceous period (dinosaur time!), some monocots acquired a special pathway for carbon fixation, rendering them more efficient particularly in hot or dry environments. In most monocots, carbon is fixed by Rubisco in the mesophyll cells. In the innovative pathway, carbon fixation is split…

Special issue: Rubisco and its regulation

Rubisco (ribulose-1,5-bisphosphate carboxylase) catalyzes the fixation of atmospheric carbon from CO2 to molecules used for biosynthesis and energy production. Several studies have focused on understanding the nature, complexity, activity, and regulation of Rubisco due to its key role in the production…

Spatial resolution of an integrated C4+CAM photosynthetic metabolism (Sci. Advances)

C4 and CAM are both photosynthetic strategies that concentrate CO2 upstream of RuBisCO, somewhat uncoupling photosynthetic carbon fixation from transpirational water loss. Both strategies use the enzyme PEP-carboxylase to produce an organic acid, which can then be decarboxylated to provide CO2 to RuBisCO.…

Rubisco accumulation factor 1 and carboxysome biogenesis (PNAS)

Carbon concentration mechanisms (CCMs) refer to a diverse set of strategies by which photosynthetic organisms increase the amount of carbon dioxide available to the carbon-fixing enzyme Rubisco. The cyanobacterial CCM relies on the carboxysome, a membraneless microcompartment with a core of densely…

Conversion of Escherichia coli to generate all biomass carbon from CO2 (Cell)

Plants are photosynthetic autotrophs, meaning they use light energy to feed themselves, with carbon dioxide as a carbon source. Heterotrophs like E. coli require organic carbon. Here, Gleizer et al. have rewired the metabolism of E. coli to make it into a (non-photosynthetic) autotroph, meaning it can…

Self-assembling organelles for CO2 fixation: stoichiometry and structural plasticity

Sun et al. investigate how carboxysomes are constructed and regulated in cyanobacteria. Plant Cell https://doi.org/10.1105/tpc.18.00787 By Luning Liu Background: All cells are composed of well-defined compartments to encase enzymes and reactions to increase the efficiency of biological processes.…

A thylakoid-located carbonic anhydrase regulates CO2 uptake in the cyanobacterium Synechocystis sp. PCC 6803 (New Phytol)

The cyanobacterial CO2 concentrating mechanism (CCM) is dependent on a continuous supply of inorganic carbon (Ci) to rubisco inside carboxysomes in order to function optimally.  CO2 uptake pathways are therefore of great importance for a full understanding of the cyanobacterial CCM.  Sun et al demonstrate…

Review:  Increasing metabolic potential: C-fixation (Essays Biochem) $

Increasing carbon fixation through the Calvin-Benson-Bassham (CBB) cycle is a viable strategy to boost crop yields, as has been demonstrated through both experimental and modelling approaches.  In this review, Andralojc et al outline the most recent advancements in this research field.  The authors…

Phytochrome, metabolism and growth plasticity

Phytochromes are plant photoreceptors that can sense red and far-red light, as-well-as the ratio of these light qualities.  This review examines the relationship between phytochrome signalling and carbon metabolism.  Krahmer et al. assess the influence of phytochrome signalling on the synthesis of…