Transport ATPase
A transport ATPase is a transport channel or protein with the ability to hydrolyze an ATP molecule into its components of ADP and and inorganic phosphate [1]. The pumps move molecules across the cell membrane using the energy released when a high energy phosphate bond is broken on ATP, removing a phosphate to produce ADP and inorganic phosphate
- ↑ Alberts B., Johnson A., Lewis J., Raff M., Roberts K., Walter P. (2008) Molecular Biology of the Cell, 5th Edition, New York, Garland Science. Pg 659
.
There are Three types of ATP pumps:
P-type: So called beacuse they self-phosphorylate at an Aspartate when moving molecules across the membrane. Examples of these pumps are Na+/K+, H+ ATPase and the Ca2+ pump. Most of the P types are respionsible for maintaining a potential across a cell membrane.
F-type: These are made of more than one subunit and use an H+ gradient across the cell (generated, for instance, in the oxidative phosphorylation step of respiration or during photosynthesis) in order to drive ATP synthesis. For this reason they are sometimes called ATP Synthases.
ABC transporters: These are a large super family of ion transporters which hydrolyse 2 ATP molecules, within their Nucleotide binding domains/casettes, in order to transport small ions across the membrane. There are many different members in this family, such as the P-Glycoprotein transporter, which is involved in multidrug resistance.