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Updated: Sep 4, 2026

Measuring Mitochondrial Electron Transfer Complexes in Previously Frozen Cardiac Tissue from the Offspring of Sow: A Model to Assess Exercise-Induced Mitochondrial Bioenergetics Changes
08:04

Measuring Mitochondrial Electron Transfer Complexes in Previously Frozen Cardiac Tissue from the Offspring of Sow: A Model to Assess Exercise-Induced Mitochondrial Bioenergetics Changes

Published on: August 16, 2021

THE EFFECT OF SONIC OSCILLATION ON THE STRUCTURE AND FUNCTION OF BEEF HEART MITOCHONDRIA

J T STASNY, F L CRANE

    The Journal of Cell Biology
    |July 1, 1964
    PubMed

    Insights

    Sonic treatment of beef heart mitochondria revealed that the mitochondrial membrane, not its subunits, drives electron transport. Fractions rich in membrane derivatives showed high activity, while detached subunits did not.

    Area of Science:

    • Biochemistry
    • Cell Biology
    • Mitochondrial Research

    Background:

    • Mitochondria are crucial for cellular respiration.
    • The structure and function of the mitochondrial membrane are key to energy production.
    • Understanding the roles of membrane components in electron transport is essential.

    Purpose of the Study:

    • To investigate the roles of mitochondrial membrane subunits and derivatives in electron transport.
    • To correlate biochemical activities with structural components observed via electron microscopy.

    Main Methods:

    • Mitochondria from beef heart were sonically treated and fractionated using differential centrifugation.
    • Electron microscopy was used to examine the structure of mitochondrial fractions.
    • Enzymatic activities and cytochrome content were measured in different fractions.

    Main Results:

    • Sonic treatment yielded variously sized particles, including knob-like subunits attached to membranes.
    • Fractions sedimented at 35,300 g and 79,420 g showed concentrated enzyme activity and cytochrome content.
    • Fractions rich in mitochondrial membrane derivatives had high activity but lacked subunits; detached subunits had low activity.

    Conclusions:

    • The mitochondrial membrane itself is responsible for electron transport activity.
    • The observed subunits do not appear to be the primary sites of electron transport.
    • Fractionation techniques can isolate functional components of the mitochondrial membrane.
    Keywords:
    CATTLECYTOCHROME OXIDASECYTOCHROMESEXPERIMENTAL LAB STUDYMITOCHONDRIAMYOCARDIUMOXIDOREDUCTASESQUINONESSOUNDSUCCINATE DEHYDROGENASE

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