The best-studied 2-Carboxy-D-arabinitol-1-phosphate phosphatase is the
enzyme that inactivates the
RuBisCO inhibitor 2-carboxy-D-arabinitol-1-phosphate (CA1P). When light levels are high, the inactivation occurs after CA1P has been released from RuBisCO by
RuBisCO activase. As CA1P is present in many but not all plants, CA1P-mediated regulation of RuBisCO is not universal for all photosynthetic life.
Amino acid sequences of the CA1Pase enzymes from wheat, French bean, tobacco, and
Arabidopsis thaliana reveal that the enzymes contain 2 different domains, indicating that it is a multifunctional
enzyme. CA1Pase enzyme activity varies between different
species due to their regulation by different redox-active compounds, such as
glutathione. However, it is yet to be determined whether this process occurs
in vivo. Wheat CA1Pase heterologously expressed in
E. coli is also able to
dephosphorylate the RuBisCO inhibitor D-glycero-2,3-diulose-1,5-bisphosphate. ==References==