RuBP full form in biology:
- Full form of RuBP in biology is Ribulose-1,5-bisphosphate.
- It is a five-carbon sugar molecule that plays an important role in the first step of the Calvin cycle.
- The regeneration of RuBP is essential for the continuous functioning of the Calvin cycle during the process of photosynthesis.
| Property | Description |
| Full Form | · Ribulose-1,5-bisphosphate |
| Discovery and naming | · RuBP was originally discovered by Andrew Benson in 1951 while working in the lab of Melvin Calvin at UC Berkeley.
· At early times, the molecule was known as ribulose diphosphate (RuDP) but the prefix di- was changed to bis- to emphasize the nonadjacency of the two phosphate groups. |
| Chemical Formula | · C5H12O11P2 |
| Role in Photosynthesis | · Key molecule in the Calvin cycle of photosynthesis.
· Acts as a CO2 acceptor during carbon fixation. |
| Carbon Fixation | · Combines with CO2 in the Calvin cycle to form a six-carbon compound |
| Enzyme | · RUBP reacts with CO2 in the presence of the enzyme RUBISCO |
| Regeneration | · RUBP is continuously regenerated through a series of reactions within the Calvin cycle to maintain the cycle’s functionality. |
| Importance | · Essential for the synthesis of glucose and other carbohydrates during photosynthesis. |
| Presence | · Present in all photosynthetic organisms where photosynthesis occurs such as
· plants · algae · cyanobacteria |
| Location in plants | · Found in the stroma of chloroplasts, which is a cellular organelle responsible for photosynthesis. |
| Location in Cyanobacteria | · Found in the stroma of thylakoids |
| Recycling of ATP and NADPH | · It participates in the regeneration phase of the Calvin cycle that requires ATP and NADPH which are generated during the light-dependent reactions of photosynthesis. |
| Carbon Storage | · RUBP is involved in storing carbon from atmospheric carbon dioxide into organic compounds.
· It contributes to biomass production in plants. |
| Regulation | · The availability of RUBP and its efficient regeneration can influence the rate of photosynthesis. |
| Interaction with RuBisCO | · RUBP binds to the active site of RuBisCO, providing the substrate for carbon dioxide fixation and subsequent carbon reduction. |
A Comparison between RuBP and Rubisco
| Aspect | RuBP | Rubisco |
| Full form | · Ribulose-1,5-bisphosphate | · Ribulose-1,5-bisphosphate carboxylase/oxygenase |
| Time of Discovery | · Around the same time as the discovery of Rubisco, as part of the research efforts on the Calvin cycle. | · 1940s |
| Location | · Present in the stroma of chloroplasts, where the Calvin cycle takes place. | · Present in the stroma of chloroplasts, primarily in the mesophyll cells of leaves. |
| Type of Molecule | · RuBP is a 5-carbon sugar phosphate. | · Rubisco is an enzyme, specifically a carboxylase/oxygenase enzyme. |
| Chemical Formula | · C5H12O11P2 | · Don’t have any formula because it is an enzyme |
| Function | · A 5-carbon sugar molecule that acts as the starting point for carbon fixation in the Calvin cycle. | · It catalyzes the addition of CO2 to RuBP thus initiates the Calvin cycle and carbon fixation.
· It is a key enzyme in photosynthesis. |
| Role in Photosynthesis | · Acts as the primary acceptor of CO2 during carbon fixation in the Calvin cycle. | · Catalyzes the carboxylation and oxygenation of RuBP, leading to the formation of two molecules of 3-phosphoglycerate (3-PGA). |
| Function during Carbon Fixation | · Acts as a receptor for CO2 molecules and is essential for their attachment to organic molecules. | · Catalyzes the carboxylation reaction, combining CO2 with RuBP to form a 6-carbon intermediate that quickly breaks down into two molecules of 3-PGA. |
| Specificity | · High specificity for CO2 molecules, which it prefers to bind during carbon fixation. | · Not highly specific and it can also bind to oxygen molecules, leading to a wasteful process called photorespiration. This reduces its efficiency. |
| Efficiency | · Efficient in capturing and fixing CO2 molecules during the Calvin cycle. | · Rubisco has a relatively low catalytic efficiency and is considered one of the slowest enzyme which leads to its limitations in photosynthetic rates. |
| Significance | · Plays a central role in carbon fixation, serving as the starting point for the synthesis of organic compounds in plants and other photosynthetic organisms. | · Improving Rubisco’s efficiency is an active area of research in crop improvement for higher yield. |