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Updated: Sep 7, 2026

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
07:35

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess

Published on: June 1, 2022

The structure of the mitochondrial membrane: inferences from permeability properties

H TEDESCHI

    The Journal of Biophysical and Biochemical Cytology
    |October 1, 1959
    PubMed

    Insights

    Mitochondrial membranes remain permeable and retain solutes even when swelling significantly. This suggests the membrane is convoluted, with its surface area changing depending on the substance

    Area of Science:

    • Cell Biology
    • Mitochondrial Physiology
    • Membrane Biophysics

    Background:

    • Mitochondria exhibit a semipermeable membrane similar to the cell membrane.
    • Mitochondria can swell significantly (4-5x volume) without lysis or solute loss, suggesting a unique membrane structure.

    Purpose of the Study:

    • To investigate the kinetic permeability of isolated mitochondria.
    • To clarify whether the mitochondrial membrane is convoluted based on its swelling behavior.

    Main Methods:

    • Utilized a previously described photometric method for kinetic studies.
    • Examined the permeability of isolated mitochondria to different types of penetrants (lipid-soluble and polar).

    Main Results:

    • For lipid-soluble compounds, mitochondrial membrane permeability and surface area remained constant during swelling.
    • For polar compounds, membrane permeability was constant, but the available surface area increased during swelling.
    • These differential responses suggest a convoluted membrane structure.

    Conclusions:

    • The mitochondrial membrane is likely convoluted, allowing for significant volume changes without compromising integrity.
    • The unfolding of convolutions during swelling increases the surface area available for polar molecule penetration.
    • The simplest model involves a convoluted bimolecular lipid layer for the mitochondrial membrane.
    Keywords:
    MITOCHONDRIA/physiologyPERMEABILITY

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