Tag: Photosynthesis

Mesophyll CO2 conductance (gm) is an important factor in determining the concentration of CO2 at the site of fixation in the chloroplast stroma, and as such is crucial for determining photosynthetic capacity.  The mesophyll cell wall provides a major site of resistance to CO2 diffusion into the stroma…

It is relatively simple to determine net O2 flux in leaves.  However, this data provides no information on the underlying processes responsible for this flux, namely gross oxygen production (GOP, water splitting), mitochondrial respiration in light, Rubisco oxygenation, and photorespiration.  In this…

Phosphorus (P) is an essential macronutrient, and P deficiency limits plant productivity. P influences many aspects of photosynthesis P-deficient plants typically remain green and do not develop leaf chlorosis and yet P starvation immediately affects CO2 assimilation. Specifically, P deficiency is believed…

The carbon-fixing enzyme Rubisco (Ribulose‐1,5‐bisphosphate carboxylase/oxygenase) is much-maligned and has been described as “sluggish” and with “confused specificity”. In this new Review, Bathellier et al. argue that it is “not really so bad”. Their reasoning is that when Rubisco’s…

Following up on earlier studies in which they introduced cyanobacterial Rubisco into tobacco, Lin and Hanson endeavoured to introduce into tobacco Rubisco genes from a red alga, which has an unusually high CO2/O2 specificity. Although they were able to demonstrate the presence of the genes and their…

Phosphorus deficiency is widespread and can severely limit plant growth.  Carstensen et al. investigated how P deficiency affects photosynthesis in barley. They compared chlorophyll a fluorescence transients (OJIP transients) between P-deficient, sufficient and resupplied plants. They observed depletion…

Du et al. investigate an important protein that regulates photosynthesis under stress. Plant Cell. https://doi.org/10.1105/tpc.17.00446.                                                                               Background:…

By Johan Ceuster and Bram Van de Poel Abstract The volatile plant hormone ethylene plays a regulatory role in many developmental processes and in biotic and abiotic stress responses. One of the under-explored actions of ethylene is its regulation of photosynthesis and associated components such…