What is the role of the enzyme RuBisCO?

RuBisCO:

Ribulose-1,5-bisphosphate carboxylase/oxygenase, better known by the name Rubisco, is the key enzyme responsible for photosynthetic and chemoautotrophic carbon fixation and oxygen metabolism.

Role of the enzyme RuBisCO:

1. RuBisCO catalyzes the first step of carbon fixation during photosynthesis. It catalyzes the carboxylation of RuBP to produce two molecules of 3-PGA.
2. When O₂ binds to RuBisCO, RuBP is converted to one molecule each of phosphoglycerate and phosphoglycolate instead of 3-PGA. The process is called photorespiration.