PH-dependent 11° F₁F_O ATP synthase sub-steps reveal insight into the F_O torque generating mechanism.

ABSTRACT: Most cellular ATP is made by rotary F₁F_O ATP synthases using proton translocation-generated clockwise torque on the F_O c-ring rotor, while F₁-ATP hydrolysis can force counterclockwise rotation and proton pumping. The F_O torque-generating mechanism remains elusive even though the F_O interface of stator subunit-a, which contains the transmembrane proton half-channels, and the c-ring is known from recent F₁F_O structures. Here, single-molecule F₁F_O rotation studies determined that the pKa values of the half-channels differ, show that mutations of residues in these channels change the pKa values of both half-channels, and reveal the ability of F_O to undergo single c-subunit r

SUBMITTER: Yanagisawa S 

PROVIDER: S-EPMC8754430 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature