| metabolic Calvin cycle
Melvin Calvin (1911-1997), a US chemist who was awarded the 1961 Nobel Prize for chemistry proved by radioactive Carbon-14 label (a process that replace stable compound atom with its radioisotope for tracing movement thru a biological or mechanical system) the existence of a metabolic cycle for ribulose 2-phosphate (RuBP). It could fix the CO2 absorbed by plants during the light-independent step of photosynthesis and by redox reactions reduces CO2 to carbohydrates (sugar compounds). The regenerated RuBPs could then be channeled back to react with more incoming CO2 and repeat the cycle over again.
RuBP is a 5-carbon sugar (or cyclopentane if only 5 hydrogen bonds are involved) that when chemically react with CO2 lead to unstable 6-carbon compounds (cyclohexane with 12 H-bonds or benzene with 6 H-bonds) produces 2 intermediate 3-carbon organic compounds (cyclopropane, 3 H-bonds) called glycerate 3-phosphate. These transported chemical energies to the next stage by adenosine 3-phosphate (ATP) and thru hydrolysis gives molecules of adenosine 2-phosphate (ADP) then these produce glyceraldehyde 3-phosphate then more ATP ® ADP and finally glucose, fructose, and regenerated RuBP. The latter once again initiates the next metabolic Calvin cycle.
This cycle seems to describe the following ring permutation sequence: 5®6®3®2®5®6®3®2®5®6®3®2®5®6®3®2®5®6®3®2®.....
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Time independence: [∂E(g)]²=[∂F(a)×∂r(a)]·[∂F(b)×∂r(b)] and Mass independence: ¶a(t)·¶r(t)=c²
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