Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Light-induced conductivity changes in purple membrane suspensions.

M A Slifkin, H Garty, W V Sherman

    Biophysics of Structure and Mechanism
    |August 1, 1979
    PubMed
    Summary
    This summary is machine-generated.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Pre-analytics of ammonia: Crioplast® devices as an alternative to icy water.

    Clinica chimica acta; international journal of clinical chemistry·2017
    Same author

    D-lactic acidosis: an unusual cause of encephalopathy in a patient with short bowel syndrome.

    Acta clinica Belgica·2013
    Same author

    Photoacoustic calorimetry of purple membrane.

    Biophysical journal·2009
    Same author

    The coupling of an enzymatic reaction to transmembrane flow of electric current in a synthetic "active transport" system.

    Biophysical journal·2009
    Same author

    Adenylosuccinate lyase deficiency: study of physiopathologic mechanism(s).

    Nucleosides, nucleotides & nucleic acids·2004
    Same author

    Adenylosuccinate lyase deficiency--first British case.

    Nucleosides, nucleotides & nucleic acids·2004
    Same journal

    Transduction in photoreceptors: determination of the pigment transition or state coupled to excitation.

    Biophysics of structure and mechanism·2012
    Same journal

    Upper limit on translational diffusion of visual pigment in intact unfixed barnacle photoreceptors.

    Biophysics of structure and mechanism·2012
    Same journal

    Properties of the on-transient of the intracellular response in the barnacle photoreceptor.

    Biophysics of structure and mechanism·2012
    Same journal

    Absorption of light by metarhodopsin modifies the effect of a conditioning light on the barnacle photoreceptor.

    Biophysics of structure and mechanism·2012
    Same journal

    The effects of Mn2+ and Ca2+ on the prolonged depolarising after-potential in barnacle photoreceptor.

    Biophysics of structure and mechanism·2012
    Same journal

    Blue adaptation: an experimental tool for the study of visual receptor mechanisms and behaviour of Drosophila.

    Biophysics of structure and mechanism·2012
    See all related articles

    Researchers detected subtle, light-induced conductivity changes in purple membranes using advanced methods. These changes, influenced by pH and temperature, reveal insights into membrane conformational dynamics.

    Area of Science:

    • Biophysics
    • Membrane biophysics
    • Photobiology

    Background:

    • Purple membranes are light-sensitive biological structures.
    • Understanding their conductivity changes is crucial for studying their function.

    Purpose of the Study:

    • To detect and characterize small, light-induced conductivity changes in purple membranes.
    • To investigate the influence of pH and temperature on these conductivity changes.
    • To correlate conductivity changes with membrane conformational dynamics.

    Main Methods:

    • Utilized modulated light and a phase-sensitive detector for high-sensitivity conductivity measurements.
    • Suspended purple membranes in strong electrolyte solutions.
    • Studied the effects of varying pH and temperature on light-induced conductivity.

    Related Experiment Videos

    Main Results:

    • Detected light-induced conductivity changes as small as 0.0001%.
    • Observed a fast conductivity increase (τ ≈ 2 ms) followed by a slower decrease (τ = 70–80 ms).
    • Found maximal conductivity changes around neutral pH, decreasing at extreme pH values.
    • Noted decreased photoconductivity with increased temperature, with Arrhenius plots showing breaks around 31°C.

    Conclusions:

    • Light-induced conductivity changes in purple membranes are complex, involving at least two distinct kinetic events.
    • These conductivity changes are sensitive to pH and temperature, indicating their role in membrane surface charge and conformational states.
    • The findings suggest that conductivity measurements can effectively monitor the kinetics of conformational changes within the purple membrane system.