Vitamin B12-transporting ATPase

In enzymology, a vitamin B12-transporting ATPase is an enzyme that catalyzes the chemical reaction


 * ATP + H2O + vitamin B12out $$\rightleftharpoons$$ ADP + phosphate + vitamin B12in

The 3 substrates of this enzyme are ATP, H2O, and vitamin B12, whereas its 3 products are ADP, phosphate, and vitamin B12.

This enzyme belongs to the family of hydrolases, specifically those acting on acid anhydrides acting on acid anhydrides to catalyse transmembrane movement of substances. The systematic name of this enzyme class is ATP phosphohydrolase (vitamin B12-importing). This enzyme participates in abc transporters - general.

Structural studies
As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes and.