Conduction pathway for potassium through the E. coli pump KdpFABC.

ABSTRACT: Under osmotic stress, bacteria express a heterotetrameric protein complex, KdpFABC, which functions as an ATP-dependent K⁺ pump to maintain intracellular potassium levels. The subunit KdpA belongs to the Superfamily of K⁺ Transporters and adopts a pseudo-tetrameric architecture with a membrane embedded selectivity filter as seen in K⁺ channels. KdpB belongs to the superfamily of P-type ATPases with a conserved binding site for ions within the membrane domain and three cytoplasmic domains that orchestrate ATP hydrolysis via an aspartyl phosphate intermediate. Previous work has hypothesized that K⁺ moves parallel to the membrane plane through a 40-Å long tunnel that connects the selectivity filter of KdpA with a canonical binding site in KdpB. In t

SUBMITTER: Hussein A 

PROVIDER: S-EPMC12247778 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature