Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Fo-driven Rotation in the ATP Synthase Direction against the Force of F1 ATPase in the FoF1 ATP Synthase.

ABSTRACT: Living organisms rely on the FoF1 ATP synthase to maintain the non-equilibrium chemical gradient of ATP to ADP and phosphate that provides the primary energy source for cellular processes. How the Fo motor uses a transmembrane electrochemical ion gradient to create clockwise torque that overcomes F1 ATPase-driven counterclockwise torque at high ATP is a major unresolved question. Using single FoF1 molecules embedded in lipid bilayer nanodiscs, we now report the observation of Fo-dependent rotation of the c10 ring in the ATP synthase (clockwise) direction against the counterclockwise force of ATPase-driven rotation that occurs upon formation of a leash with Fo stator subunit a. Mutational studies indicate that the leash is important for ATP synthase activity and support a mechanism in which residues aGlu-196 and cArg-50 participate in the cytoplasmic proton half-channel to promote leash formation.

SUBMITTER: Martin J

PROVIDER: S-EPMC4409238 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Fo-driven Rotation in the ATP Synthase Direction against the Force of F1 ATPase in the FoF1 ATP Synthase.

Martin James J Hudson Jennifer J Hornung Tassilo T Frasch Wayne D WD

The Journal of biological chemistry 20150224 17

Living organisms rely on the FoF1 ATP synthase to maintain the non-equilibrium chemical gradient of ATP to ADP and phosphate that provides the primary energy source for cellular processes. How the Fo motor uses a transmembrane electrochemical ion gradient to create clockwise torque that overcomes F1 ATPase-driven counterclockwise torque at high ATP is a major unresolved question. Using single FoF1 molecules embedded in lipid bilayer nanodiscs, we now report the observation of Fo-dependent rotati ...[more]

PMID: 25713065

Similar Datasets

ATP-driven stepwise rotation of FoF1-ATP synthase.

Project description:FoF1-ATP synthase (FoF1) is a motor enzyme that couples ATP synthesis/hydrolysis with a transmembrane proton translocation. F1, a water-soluble ATPase portion of FoF1, rotates by repeating ATP-waiting dwell, 80 degrees substep rotation, catalytic dwell, and 40 degrees -substep rotation. Compared with F1, rotation of FoF1 has yet been poorly understood, and, here, we analyzed ATP-driven rotations of FoF1. Rotation was probed with an 80-nm bead attached to the ring of c subunits in the immobilized FoF1 and recorded with a submillisecond fast camera. The rotation rates at various ATP concentrations obeyed the curve defined by a Km of approximately 30 microM and a Vmax of approximately 350 revolutions per second (at 37 degrees C). At low ATP, ATP-waiting dwell was seen and the kon-ATP was estimated to be 3.6 x 10(7) M(-1) x s(-1). At high ATP, fast, poorly defined stepwise motions were observed that probably reflect the catalytic dwells. When a slowly hydrolyzable substrate, adenosine 5'-[gamma-thio]triphosphate, was used, the catalytic dwells consisting of two events were seen more clearly at the angular position of approximately 80 degrees . The rotational behavior of FoF1 resembles that of F1. This finding indicates that "friction" in Fo motor is negligible during the ATP-driven rotation. Tributyltin chloride, a specific inhibitor of proton translocation, slowed the rotation rate by 96%. However, dwells at clearly defined angular positions were not observed under these conditions, indicating that inhibition by tributyltin chloride is complex.

| S-EPMC545493 | biostudies-literature

36 degrees step size of proton-driven c-ring rotation in FoF1-ATP synthase.

Project description:Synthesis of adenosine triphosphate ATP, the 'biological energy currency', is accomplished by F(o)F(1)-ATP synthase. In the plasma membrane of Escherichia coli, proton-driven rotation of a ring of 10 c subunits in the F(o) motor powers catalysis in the F(1) motor. Although F(1) uses 120 degrees stepping during ATP synthesis, models of F(o) predict either an incremental rotation of c subunits in 36 degrees steps or larger step sizes comprising several fast substeps. Using single-molecule fluorescence resonance energy transfer, we provide the first experimental determination of a 36 degrees sequential stepping mode of the c-ring during ATP synthesis.

| S-EPMC2750017 | biostudies-literature

Reversible optical control of F1 Fo -ATP synthase using photoswitchable inhibitors.

Project description:F1 Fo -ATP synthase is one of the best studied macromolecular machines in nature. It can be inhibited by a range of small molecules, which include the polyphenols, resveratrol and piceatannol. Here, we introduce Photoswitchable Inhibitors of ATP Synthase, termed PIAS, which were synthetically derived from these polyphenols. They can be used to reversibly control the enzymatic activity of purified yeast Yarrowia lipolyticaATP synthase by light. Our experiments indicate that the PIAS bind to the same site in the ATP synthase F1 complex as the polyphenols in their trans form, but they do not bind in their cis form. The PIAS could be useful tools for the optical precision control of ATP synthase in a variety of biochemical and biotechnological applications.

| S-EPMC6175411 | biostudies-literature

Insights into the molecular mechanism of rotation in the Fo sector of ATP synthase.

Project description:F(1)F(o)-ATP synthase is a ubiquitous membrane protein complex that efficiently converts a cell's transmembrane proton gradient into chemical energy stored as ATP. The protein is made of two molecular motors, F(o) and F(1), which are coupled by a central stalk. The membrane unit, F(o), converts the transmembrane electrochemical potential into mechanical rotation of a rotor in F(o) and the physically connected central stalk. Based on available data of individual components, we have built an all-atom model of F(o) and investigated through molecular dynamics simulations and mathematical modeling the mechanism of torque generation in F(o). The mechanism that emerged generates the torque at the interface of the a- and c-subunits of F(o) through side groups aSer-206, aArg-210, and aAsn-214 of the a-subunit and side groups cAsp-61 of the c-subunits. The mechanism couples protonation/deprotonation of two cAsp-61 side groups, juxtaposed to the a-subunit at any moment in time, to rotations of individual c-subunit helices as well as rotation of the entire c-subunit. The aArg-210 side group orients the cAsp-61 side groups and, thereby, establishes proton transfer via aSer-206 and aAsn-214 to proton half-channels, while preventing direct proton transfer between the half-channels. A mathematical model proves the feasibility of torque generation by the stated mechanism against loads typical during ATP synthesis; the essential model characteristics, e.g., helix and subunit rotation and associated friction constants, have been tested and furnished by steered molecular dynamics simulations.

| S-EPMC1303972 | biostudies-literature

Twisting and subunit rotation in single F(O)(F1)-ATP synthase.

Project description:F(O)F(1)-ATP synthases are ubiquitous proton- or ion-powered membrane enzymes providing ATP for all kinds of cellular processes. The mechanochemistry of catalysis is driven by two rotary nanomotors coupled within the enzyme. Their different step sizes have been observed by single-molecule microscopy including videomicroscopy of fluctuating nanobeads attached to single enzymes and single-molecule Förster resonance energy transfer. Here we review recent developments of approaches to monitor the step size of subunit rotation and the transient elastic energy storage mechanism in single F(O)F(1)-ATP synthases.

| S-EPMC3538427 | biostudies-literature

Rotary catalysis of FoF1-ATP synthase.

Project description:The synthesis of ATP, the key reaction of biological energy metabolism, is accomplished by the rotary motor protein; FoF1-ATP synthase (FoF1). In vivo, FoF1, located on the cell membrane, carries out ATP synthesis by using the proton motive force. This heterologous energy conversion is supposed to be mediated by the mechanical rotation of FoF1; however, it still remained unclear. Recently, we developed the novel experimental setup to reproduce the proton motive force in vitro and succeeded in directly observing the proton-driven rotation of FoF1. In this review, we describe the interesting working principles determined so far for FoF1 and then introduce results from our recent study.

| S-EPMC4629669 | biostudies-literature

How does transmembrane electrochemical potential drive the rotation of Fo motor in an ATP synthase?

Project description:While the field of ATP synthase research has a long history filled with landmark discoveries, recent structural works provide us with important insights into the mechanisms that links the proton movement with the rotation of the Fo motor. Here, we propose a mechanism of unidirectional rotation of the Fo complex, which is in agreement with these new structural insights as well as our more general ΔΨ-driving hypothesis of membrane proteins: A proton path in the rotor-stator interface is formed dynamically in concert with the rotation of the Fo rotor. The trajectory of the proton viewed in the reference system of the rotor (R-path) must lag behind that of the stator (S-path). The proton moves from a higher energy site to a lower site following both trajectories simultaneously. The two trajectories meet each other at the transient proton-binding site, resulting in a relative rotation between the rotor and stator. The kinetic energy of protons gained from ΔΨ is transferred to the c-ring as the protons are captured sequentially by the binding sites along the proton path, thus driving the unidirectional rotation of the c-ring. Our ΔΨ-driving hypothesis on Fo motor is an attempt to unveil the robust mechanism of energy conversion in the highly conserved, ubiquitously expressed rotary ATP synthases.

| S-EPMC4624678 | biostudies-literature

Elasticity, friction, and pathway of γ-subunit rotation in FoF1-ATP synthase.

Project description:We combine molecular simulations and mechanical modeling to explore the mechanism of energy conversion in the coupled rotary motors of FoF1-ATP synthase. A torsional viscoelastic model with frictional dissipation quantitatively reproduces the dynamics and energetics seen in atomistic molecular dynamics simulations of torque-driven γ-subunit rotation in the F1-ATPase rotary motor. The torsional elastic coefficients determined from the simulations agree with results from independent single-molecule experiments probing different segments of the γ-subunit, which resolves a long-lasting controversy. At steady rotational speeds of ∼ 1 kHz corresponding to experimental turnover, the calculated frictional dissipation of less than k(B)T per rotation is consistent with the high thermodynamic efficiency of the fully reversible motor. Without load, the maximum rotational speed during transitions between dwells is reached at ∼ 1 MHz. Energetic constraints dictate a unique pathway for the coupled rotations of the Fo and F1 rotary motors in ATP synthase, and explain the need for the finer stepping of the F1 motor in the mammalian system, as seen in recent experiments. Compensating for incommensurate eightfold and threefold rotational symmetries in Fo and F1, respectively, a significant fraction of the external mechanical work is transiently stored as elastic energy in the γ-subunit. The general framework developed here should be applicable to other molecular machines.

| S-EPMC4553772 | biostudies-other

Anatomy of F1-ATPase powered rotation.

Project description:F1-ATPase, the catalytic complex of the ATP synthase, is a molecular motor that can consume ATP to drive rotation of the γ-subunit inside the ring of three αβ-subunit heterodimers in 120° power strokes. To elucidate the mechanism of ATPase-powered rotation, we determined the angular velocity as a function of rotational position from single-molecule data collected at 200,000 frames per second with unprecedented signal-to-noise. Power stroke rotation is more complex than previously understood. This paper reports the unexpected discovery that a series of angular accelerations and decelerations occur during the power stroke. The decreases in angular velocity that occurred with the lower-affinity substrate ITP, which could not be explained by an increase in substrate-binding dwells, provides direct evidence that rotation depends on substrate binding affinity. The presence of elevated ADP concentrations not only increased dwells at 35° from the catalytic dwell consistent with competitive product inhibition but also decreased the angular velocity from 85° to 120°, indicating that ADP can remain bound to the catalytic site where product release occurs for the duration of the power stroke. The angular velocity profile also supports a model in which rotation is powered by Van der Waals repulsive forces during the final 85° of rotation, consistent with a transition from F1 structures 2HLD1 and 1H8E (Protein Data Bank).

| S-EPMC3956197 | biostudies-literature

Complementation of the Fo c subunit of Escherichia coli with that of Streptococcus mutans and properties of the hybrid FoF1 ATP synthase.

Project description:The c subunit of Streptococcus mutans ATP synthase (FoF1) is functionally exchangeable with that of Escherichia coli, since E. coli with a hybrid FoF1 is able to grow on minimum succinate medium through oxidative phosphorylation. E. coli F1 bound to the hybrid Fo with the S. mutans c subunit showed N,N'-dicyclohexylcarbodiimide-sensitive ATPase activity similar to that of E. coli FoF1. Thus, the S. mutans c subunit assembled into a functional Fo together with the E. coli a and b subunits, forming a normal F1 binding site. Although the H(+) pathway should be functional, as was suggested by the growth on minimum succinate medium, ATP-driven H(+) transport could not be detected with inverted membrane vesicles in vitro. This observation is partly explained by the presence of an acidic residue (Glu-20) in the first transmembrane helix of the S. mutans c subunit, since the site-directed mutant carrying Gln-20 partly recovered the ATP-driven H(+) transport. Since S. mutans is recognized to be a primary etiological agent of human dental caries and is one cause of bacterial endocarditis, our system that expresses hybrid Fo with the S. mutans c subunit would be helpful to find antibiotics and chemicals specifically directed to S. mutans.

| S-EPMC3807490 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data