activity of reconstituted rubisco enzyme from .

RuBisCO (Ribulose 1,5 bisphosphate carboxylase/oxygenase) by virtue of its dual specificity towards oxygen and carbon dioxide is an important rate-limiting step in photosynthesis and is believed to be the key factor for limited productivity of higher plants and algae. The photoautotrophic growth rate of cyanobacteria is a culmination of several factors including, rates of photosynthetic reactions, stress combating mechanisms and basic biomass generation metabolism in combination with optimal nutrient availability, irradiance, gaseous environment, etc. In case of cyanobacteria, the effect of RuBisCO in affecting the multiplication rate has been observed to show varied response.

Regulatory components of carbon concentrating mechanisms in aquatic unicellular photosynthetic organisms.

This review provides an insight into the regulation of the carbon concentrating mechanisms (CCMs) in lower organisms like cyanobacteria, proteobacteria, and algae. CCMs evolved as a mechanism to concentrate CO at the site of primary carboxylating enzyme Ribulose-1, 5-bisphosphate carboxylase oxygenase (Rubisco), so that the enzyme could overcome its affinity towards O which leads to wasteful processes like photorespiration. A diverse set of CCMs exist in nature, i.

Role of habitat and great oxidation event on the occurrence of three multisubunit inorganic carbon-uptake systems in cyanobacteria.

The oxygenase reaction catalyzed by RuBisCO became an issue only after the evolution of the oxygenic photosynthesis in cyanobacteria. Several strategies were developed by autotrophic organisms as an evolutionary response to increase oxygen levels to help RuBisCO maximize its net carboxylation rate. One of the crucial advancements in this context was the development of more efficient inorganic carbon transporters which could help in increasing the influx of inorganic carbon (Ci) at the site of CO₂ fixation.