Potassium-transporting ATPase subunit A (KdpA)

Potassium-transporting ATPase subunit A (KdpA) is the primary ion-binding and translocation component of the KdpABC complex, a high-affinity P-type ATPase found in various bacteria, including pathogens like Mycobacterium tuberculosis and Staphylococcus aureus. Unlike typical P-type ATPases where a single polypeptide performs both ATP hydrolysis and ion transport, the Kdp system decouples these functions; KdpA acts as the channel-like subunit that mediates K+ uptake, while KdpB provides the energy through ATP hydrolysis. This system is essential for bacterial survival under conditions of extreme potassium limitation or osmotic stress, making it a critical factor for environmental adaptation and virulence. Because the KdpABC complex is structurally distinct from eukaryotic ion transporters, it represents a promising target for the development of narrow-spectrum antibacterial agents. Inhibiting KdpA would disrupt the bacterium's ability to maintain ion homeostasis, leading to impaired growth and increased susceptibility to host immune defenses. Current research focuses on identifying small molecules that can specifically block the KdpA translocation pore or uncouple the subunit interactions within the complex.

Other names

Bacterial potassium-transporting ATPase alpha chain 1KdpABC complex subunit APotassium-translocating ATPase subunit AK+ transporting ATPase subunit A

Inhibition of the KdpABC complex to disrupt bacterial potassium homeostasis and osmoregulation.