RuBisCO
RuBisCO (Ribulose-1,5-bisphosphate carboxylase-oxygenase) is the Enzyme responsible for fixing carbon dioxide in the Calvin Cycle.
It catalyzes the reaction between CO2 and RuBP, forming two molecules of 3-phosphoglycerate (3-PGA).
Despite its essential role in Photosynthesis, RuBisCO is relatively inefficient and prone to binding oxygen instead of CO2 in a process called Photorespiration.