Question

Which of the following types of ATPase pumps are sensitive to vanadate (which inhibits phosphorylation of the pump during its activity mechanism)?

A) P type
B) V type
C) F type
D) ABC type
E) All are inhibited by vanadate.

Answer 1

Vanadate specifically inhibits P type ATPases by acting as an analog for the phosphate in the phosphorylation cycle, and does not effectively inhibit V type, F type, or ABC type ATPases.

Step-by-step explanation:

The type of ATPase pumps that are sensitive to vanadate, which inhibits phosphorylation during their activity mechanism, are known as P type ATPases. Vanadate acts as a transition state analog for the phosphate that is normally transferred to the Asp residue in these pumps during the phosphorylation cycle, thus, it specifically inhibits P type ATPases. Vanadate does not effectively inhibit other types of ATPases, such as V type, F type, or ABC type. These ATPases all operate differently, with the P type participating in active transport by phosphorylation and dephosphorylation, while others like F type utilize a proton gradient to synthesize ATP, and V type also uses a proton gradient to pump protons across membranes for acidification of compartments like vesicles and vacuoles.