Related Experiment Video

Updated: Aug 4, 2026

Multi-parameter Measurement of the Permeability Transition Pore Opening in Isolated Mouse Heart Mitochondria
13:42

Multi-parameter Measurement of the Permeability Transition Pore Opening in Isolated Mouse Heart Mitochondria

Published on: September 7, 2012

A kinetic study on the hydrolytic activity of mitochondrial ATPase (F0-F1 complex) from pig heart

J J Ye, Z H Lin

    Biochemistry International
    |May 1, 1986
    PubMed

    Insights

    Mitochondrial ATPase activity is differently affected by magnesium and ATP depending on its state. Membrane-bound ATPase shows distinct cooperativity compared to free enzyme, suggesting conformational changes.

    Area of Science:

    • Biochemistry
    • Enzymology
    • Mitochondrial Physiology

    Background:

    • Mitochondrial ATPase (F0-F1 complex) is crucial for cellular energy production.
    • Understanding its regulation is key to comprehending mitochondrial function.
    • Previous studies focused on the free F1 subunit, leaving the membrane-bound complex less characterized.

    Purpose of the Study:

    • To investigate the kinetic behavior of pig heart mitochondrial ATPase (F0-F1 complex).
    • To compare the effects of magnesium (Mg2+) and adenosine triphosphate (ATP) on the enzyme in its membrane-bound state versus the free F1 state.
    • To elucidate the role of enzyme conformation in catalytic activity and cooperativity.

    Main Methods:

    • Kinetic analysis of mitochondrial ATPase activity.
    • Incubation of the enzyme with varying concentrations of free Mg2+ and free ATP.
    • Comparison of kinetic data with previously reported results for free F1 ATPase.

    Main Results:

    • Free Mg2+ competitively activated mitochondrial ATPase with no cooperativity.
    • Free ATP competitively inhibited the enzyme, exhibiting positive cooperativity.
    • These findings contrast with the behavior of free F1, indicating state-dependent effects.

    Conclusions:

    • The conformation of F1 differs between the membrane-bound and free states, influenced by F0 and lipids.
    • Mg2+ and ATP exert distinct effects on F1 depending on its conformational state.
    • Altered conformation in the membrane-bound state leads to different catalytic site cooperativity, impacting enzyme mechanism.

    More Related Videos

    F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes08:21

    F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

    Published on: May 4, 2013

    Isolation of F1-ATPase from the Parasitic Protist Trypanosoma brucei08:44

    Isolation of F1-ATPase from the Parasitic Protist Trypanosoma brucei

    Published on: January 22, 2019

    Related Concept Videos

    ATP Driven Pumps I: An Overview01:27

    ATP Driven Pumps I: An Overview

    ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
    There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...
    ATP Synthase: Mechanism01:48

    ATP Synthase: Mechanism

    In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased ATP...
    ATP Synthase: Structure01:18

    ATP Synthase: Structure

    ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...
    ATP Driven Pumps III: V-type Pumps01:30

    ATP Driven Pumps III: V-type Pumps

    V-type pumps are ATP-driven pumps found in the vacuolar membranes of plants, yeast, endosomal and lysosomal membranes of animal cells, plasma membranes of a few specialized eukaryotic cells, and some prokaryotes. They are also known as the V1Vo-ATPase, that couple ATP hydrolysis to transport protons against a concentration gradient.
    The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...