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The crystal structure of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) from Arabidopsis thaliana is reported at 1.5 Å resolution. In light of the importance of A. thaliana as a model organism for understanding higher plant biology, and the pivotal role of Rubisco in photosynthetic carbon
BACKGROUND
Chloroplasts were formed by uptake of cyanobacteria into eukaryotic cells ca. 1.6 billion years ago. During evolution most of the cyanobacterial genes were transferred from the chloroplast to the nuclear genome. The rbcX gene, encoding an assembly chaperone required for Rubisco
Enhancement of Rubisco kinetics could improve photosynthetic efficiency, ultimately resulting in increased crop yield. However, imprecise knowledge of the reaction mechanism and the individual rate constants limits our ability to optimize the enzyme. Membrane inlet mass spectrometry (MIMS) may offer
Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) catalyzes the reaction between gaseous carbon dioxide (CO2 ) and ribulose-1,5-bisphosphate. Although it is one of the most studied enzymes, the assembly mechanisms of the large hexadecameric RuBisCO is still emerging. In bacteria and in the
Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase; EC 4.1.1.39), the most abundant protein in nature, catalyzes the assimilation of CO(2) (worldwide about 10(11) t each year) by carboxylation of ribulose-1,5-bisphosphate. It is a hexadecamer consisting of eight large and eight small subunits.
During leaf senescence, Rubisco is gradually degraded and its components are recycled within the plant. Although Rubisco can be mobilized to the vacuole by autophagy via specific autophagic bodies, the importance of this process in Rubisco degradation has not been shown directly. Here, we monitored
Biochemical models are used to predict and understand the response of photosynthesis to rising temperatures and CO2 partial pressures. These models require the temperature dependency of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) kinetics and mesophyll conductance to CO2 (g(m)).
The CO2-fixing enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is inactivated by the formation of dead-end complexes with inhibitory sugar phosphates. In plants and green algae, the ATP-dependent motor protein Rubisco activase restores catalytic competence by facilitating
Temperature is one of the most important factors controlling growth, development, and reproduction in plants. The rate of photosynthesis declines at moderately high temperatures in plants and particularly in temperate species like Arabidopsis thaliana. This can be attributed to a reduced ability of
Over the past decade various approaches have been used to increase the expression level of recombinant proteins in plants. One successful approach has been to target proteins to specific subcellular sites/compartments of plant cells, such as the chloroplast. In the study reported here,
Metabolic and physiological analyses of glutamate:glyoxylate aminotransferase 1 (GGT1) mutants were performed at the global leaf scale to elucidate the mechanisms involved in their photorespiratory growth phenotype. Air-grown ggt1 mutants showed retarded growth and development, that was not observed
One of the earliest events in the process of leaf senescence is dismantling of chloroplasts. Mesophyll cell chloroplasts from rosette leaves were studied in Arabidopsis thaliana undergoing natural senescence. The number of chloroplasts decreased by only 17% in fully yellow leaves, and chloroplasts
There is evidence suggesting that in plants changes in the photosynthetic source/sink balance are an important factor that regulates leaf photosynthetic rate through affects on the leaf carbohydrate status. However, to resolve the regulatory mechanism of leaf photosynthetic rate associated with
Autophagy is an intracellular process facilitating the vacuolar degradation of cytoplasmic components and is important for nutrient recycling during starvation. We previously demonstrated that chloroplasts can be partially mobilized to the vacuole by autophagy via spherical bodies named