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Crystallizing Membrane Proteins for Structure Determination using Lipidic Mesophases
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Crystallizing Membrane Proteins for Structure Determination using Lipidic Mesophases

Published on: November 21, 2010

Structure of the Chromatium sulfur particle and its protein membrane

G L Nicolson, G L Schmidt

    Journal of Bacteriology
    |March 1, 1971
    PubMed

    Insights

    Researchers discovered a unique protein membrane surrounding sulfur particles in Chromatium vinosum. This membrane, composed of globular components, influences sulfur particle structure and staining properties.

    Area of Science:

    • Microbiology
    • Biochemistry
    • Structural Biology

    Background:

    • Chromatium vinosum strain D stores sulfur particles intracellularly.
    • The structure and composition of these sulfur-storage membranes are not fully understood.

    Purpose of the Study:

    • To characterize the unique proteinaceous membrane surrounding sulfur particles in Chromatium vinosum.
    • To elucidate the ultrastructure and composition of this sulfur-binding membrane.

    Main Methods:

    • Ultrastructural examination using Epon and bovine serum albumin sections.
    • Negative staining of sulfur-free membrane ghosts.

    Main Results:

    • Sulfur particles are enclosed by a distinct proteinaceous membrane.
    • The membrane is a monomolecular sheet of 2.5-nm globular components.
    • Internal sulfur binds negative stains and forms myelin-like structures upon membrane rupture.

    Conclusions:

    • The proteinaceous membrane plays a role in sulfur particle structure and stability.
    • The membrane's composition influences the interaction of sulfur with negative stains.
    • Further research into microbial sulfur storage mechanisms is warranted.

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