Navigation Links
Calvin cycle


The Calvin cycle (also known as Calvin-Benson cycle) is a series of biochemical reactions taking place in the chloroplasts of photosynthetic organisms. It was discovered by Melvin Calvin and Andy Benson at the University of California, Berkeley. It is one of the light-independent reactions and occurs in the stroma.

During photosynthesis, light energy has been converted into chemical energy stored in ATP and NADPH. The light-independent Calvin cycle uses the energy from these short-lived energy carriers to convert carbon dioxide into organic compounds that can be used by the organism. This set of reactions is also called carbon fixation. The key enzyme of the cycle is called RubisCO.

The total sum of reactions in the Calvin cycle is the following:

6 CO2 + 12 NADPH + 12 H2O + 18 ATP → C6H12O6 + 12 NADP+ + 18 ADP + 18 Pi

Reactions in the Calvin Cycle

Ribulose 1,5 bisphosphate (RuBP) + carbon dioxide → 3-phosphoroglycerate (catalysed by RubisCO)

3 C5H8P2O11 + 3 CO2 → 6 C3H3P1O6 + H2O

3-phosphoroglycerate + ATP → 1,3 bisphosphoroglycerate + ADP

6 C3H3P1O6 + 6 ATP → 6 C3H3P2O10 + 6 ADP

1,3 bisphosphoroglycerate + NADPH → 3-phosphoglyceraldehyde + NADP+ + Pi

6 C3H3P2O10 + 6 NADPH → 6 C3H5P1O6 + 6 NADP+ + 6 Pi

3-phosphoglyceraldehyde → ribulose 5-phosphate + Pi

5 C3H5P1O6 → 3 C5H8P1O7 + 2 Pi

ribulose 5-phosphate + ACP→ ribulose 1,5 bisphosphate + ADP

3 C5H8P1O7 + 3 ATP → 3 C5H8P2O11 + 3 ADP

The missing 3-phosphoglyceraldehyde molecule is converted into glucose.


The known Calvin cycle as of 1997 is as follows:

- Ribulose 5-Phosphate → (3 ATP → 3ADP) → Ribulose 1,5-bisphosphate.

- Ribulose 1,5-bisphosphate + 3 Carbon Dioxide → 3-Phosphoglycerate.

- 3-Phosphoglycerate → (6 ATP → 6 ADP) → 1,3-Bisphosphoglycerate.

- 1,3-Bisphosphoglycerate → (6 NADPH → 6 NADP+) → 3 GAP + 3 DHAP + 6 Pi

- GAP + DHAP → Fructose 1,6-bisphosphate.

- Fructose 1,6-bisphosphate → (H2O → Pi) → Fructose 6-phosphate.

- GAP + Fructose 6-phosphate → Erythrose 4-phosphate + Xylulose 5-phosphate.

- DHAP + Erythrose 4-phosphate → Sedoheptulose 1,7-bisphosphate.

- Sedoheptulose 1,7-bisphosphate → (H2O → Pi) → Sedoheptulose 7-phosphate.

- Sedoheptuose 7-phosphate + GAP → Ribose 5-phosphate + Xylulose 5-phosphate.

- Xylulose 5-phosphate → (spontaneous degradation) → Ribulose 5-phosphate.

- Ribose 5-phosphate → (spontaneous degradation) → Ribulose 5-Phosphate.


'"/>


(Date:12/18/2018)... ... December 18, 2018 , ... CP Merritt is a national champion ... for many years however in 2006, he had a medical setback that caused him ... that he suffered from cartilage degeneration in his right rear fetlock. Such an ...
(Date:12/13/2018)... ... December 12, 2018 , ... NDA Partners Chief ... firm’s prominent Expert Consultants, was recently honored by the American Association of Pharmaceutical ... working in pharmaceutical science, technology, engineering, or education and whose contributions to the ...
(Date:12/13/2018)... ... ... New research by Florida Polytechnic University faculty and students has the goal of ... main causes of car accidents and fatalities on the roads. , ... computer science, uses a microcomputer, a camera, and a buzzer. The camera aims at ...
Breaking Biology News(10 mins):
Other biology definition