Key enzyme of photosynthesis involved in carbon fixation
Ribulose-1,5-bisphosphate carboxylase oxygenase
A 3d depiction of the activated RuBisCO from spinach in open form with active site accessible. The active site Lys175 residues are marked in pink, and a close-up of the residue is provided to the right for one of the monomers composing the enzyme.
^Cooper GM (2000). "10.The Chloroplast Genome". The Cell: A Molecular Approach (2nd ed.). Washington, D.C.: ASM Press. ISBN978-0-87893-106-4. , one of the subunits of ribulose bisphosphate carboxylase (rubisco) is encoded by chloroplast DNA. Rubisco is the critical enzyme that catalyzes the addition of CO2 to ribulose-1,5-bisphosphate during the Calvin cycle. It is also thought to be the single most abundant protein on Earth, so it is noteworthy that one of its subunits is encoded by the chloroplast genome.